阅读说明：本技术 光学构件和包括该光学构件的显示器 (Optical member and display including the same ) 是由 洪瑄英 李栋熙 李栢熙 于 2019-03-19 设计创作，主要内容包括：本发明提供光学构件和包括该光学构件的显示器。一种光学构件包括导光板；低折射层,其设置在导光板上并且具有小于导光板的折射率的折射率；低折射底层,其设置在低折射层和导光板之间并且具有小于低折射层的厚度的厚度；以及波长转换层,其设置在低折射层上。(The invention provides an optical member and a display including the same. An optical member includes a light guide plate; a low refractive layer disposed on the light guide plate and having a refractive index less than that of the light guide plate; a low-refractive base layer disposed between the low-refractive layer and the light guide plate and having a thickness less than that of the low-refractive layer; and a wavelength conversion layer disposed on the low refractive layer.)

1. an optical member comprising:

A light guide plate;

A low refractive layer disposed on the light guide plate and having a refractive index less than that of the light guide plate;

A low-refractive underlayer disposed between the low-refractive layer and the light guide plate and having a thickness less than that of the low-refractive layer; and

A wavelength conversion layer disposed on the low refractive layer.

2. The optical member according to claim 1, wherein:

The lower surface of the low-refraction bottom layer is contacted with the upper surface of the light guide plate; and is

The upper surface of the low-refraction bottom layer contacts the lower surface of the low-refraction layer.

3. The optical member according to claim 2, wherein the low-refractive underlayer comprises at least one of a low-refractive material having a refractive index of 1.3 to 1.7 and a high-refractive material having a refractive index of 1.5 to 2.2.

4. The optical member according to claim 3, wherein the refractive index of the low-refractive underlayer is larger than the refractive index of the low-refractive layer.

5. the optical member according to claim 4, wherein the low-refractive base layer includes a first low-refractive base layer disposed on the light guide plate and a second low-refractive base layer disposed on the first low-refractive base layer.

6. The optical member according to claim 5, wherein one of the first low-refractive underlayer and the second low-refractive underlayer comprises the low-refractive material, and the other of the first low-refractive underlayer and the second low-refractive underlayer comprises the high-refractive material.

7. The optical member according to claim 6, wherein each of the first low-refractive underlayer and the second low-refractive underlayer has a thickness of 0.2 μm or less.

8. The optical member according to claim 6, wherein the low-refractive material comprises silicon oxide, and the high-refractive material comprises silicon nitride.

9. The optical member according to claim 1, wherein the difference in refractive index between the light guide plate and the low refractive layer is 0.2 or more.

10. The optical member according to claim 9, wherein the low-refractive layer includes voids.

11. The optical member according to claim 9, wherein the refractive index of the low-refractive layer is 1.2 to 1.3.

12. The optical member according to claim 11, wherein the thickness of the low refractive layer is 0.8 μm to 1.2 μm.

13. The optical member of claim 1, further comprising a wavelength converting cladding layer disposed on the wavelength converting layer.

14. The optical member according to claim 13, wherein a lower surface of the wavelength conversion coating layer is parallel to an upper surface of the light guide plate.

15. The optical member according to claim 14, wherein the wavelength conversion cover layer comprises at least one of silicon oxide and silicon nitride.

16. The optical member of claim 15, wherein the wavelength converting cladding layer comprises:

a first wavelength converting cladding layer disposed on the wavelength converting layer; and

A second wavelength converting cladding layer disposed on the first wavelength converting cladding layer.

17. The optical member according to claim 16, wherein one of said first and second wavelength converting cladding layers comprises a transparent organic material, and the other of said first and second wavelength converting cladding layers comprises at least one of silicon oxide and silicon nitride.

18. The optical member according to claim 17, wherein:

the first wavelength converting cladding layer comprises silicon oxide; and

The second wavelength converting cladding layer includes a transparent organic material.

19. The optical member according to claim 16, wherein one of said first and second wavelength converting cladding layers comprises silicon oxide and the other of said first and second wavelength converting cladding layers comprises silicon nitride.

20. The optical member of claim 16, wherein the wavelength-converting cladding layer further comprises a third wavelength-converting cladding layer disposed on the second wavelength-converting cladding layer.

21. The optical member of claim 20, wherein the first wavelength converting cladding layer comprises a transparent organic material.

22. The optical member according to claim 21, wherein one of the second and third wavelength-converting cladding layers comprises silicon oxide, and the other of the second and third wavelength-converting cladding layers comprises silicon nitride.

23. The optical member according to claim 1, wherein the light guide plate comprises glass.

24. The optical member according to claim 23, wherein an upper surface of the light guide plate is parallel to a lower surface of the low refractive layer.

25. an optical member comprising:

A light guide plate;

A low refractive layer disposed on the light guide plate and having a refractive index less than that of the light guide plate;

A wavelength conversion layer disposed on the low refractive layer; and

A low-refractive cover layer disposed between the low-refractive layer and the wavelength conversion layer and having a thickness less than that of the low-refractive layer.

26. The optical member according to claim 25, wherein the low-refractive cover layer includes at least one of a low-refractive material having a refractive index of 1.3 to 1.7 and a high-refractive material having a refractive index of 1.5 to 2.2.

27. The optical member according to claim 26, wherein a refractive index of the low-refractive cover layer is larger than a refractive index of the low-refractive layer.

28. The optical member according to claim 27, wherein the low-refractive cover layer comprises:

A first low-refractive cover layer disposed on the low-refractive layer; and

A second low-refractive cover layer disposed on the first low-refractive cover layer.

29. The optical member according to claim 28, wherein one of the first low-refractive cover layer and the second low-refractive cover layer includes the low-refractive material, and the other of the first low-refractive cover layer and the second low-refractive cover layer includes the high-refractive material.

30. The optical member according to claim 29, wherein each of the first low-refractive cover layer and the second low-refractive cover layer has a thickness of 0.2 μm or less.

31. The optical member according to claim 30, wherein the low-refractive material comprises silicon oxide and the high-refractive material comprises silicon nitride.

32. The optical member of claim 25, further comprising a wavelength converting cladding layer disposed on the wavelength converting layer.

33. The optical member according to claim 32, wherein the wavelength conversion coating layer comprises at least one of silicon oxide and silicon nitride.

34. The optical member of claim 33, wherein the wavelength-converting cladding layer comprises:

A first wavelength converting cladding layer disposed on the wavelength converting layer; and

A second wavelength converting cladding layer disposed on the first wavelength converting cladding layer.

35. The optical member according to claim 34, wherein one of said first and second wavelength converting cladding layers comprises a transparent organic material, and the other of said first and second wavelength converting cladding layers comprises at least one of silicon oxide and silicon nitride.

36. the optical member according to claim 35, wherein:

The first wavelength converting cladding layer comprises silicon oxide; and is

The second wavelength converting cladding layer includes a transparent organic material.

37. The optical member of claim 34, wherein the wavelength-converting cladding layer further comprises a third wavelength-converting cladding layer disposed on the second wavelength-converting cladding layer.

38. An optical component, comprising:

A light guide plate;

A low refractive layer disposed on the light guide plate and having a refractive index less than that of the light guide plate;

A wavelength conversion layer disposed on the low refractive layer;

A low-refractive bottom layer disposed between the low-refractive layer and the light guide plate; and

A low refractive cover layer disposed between the low refractive layer and the wavelength conversion layer.

39. The optical member according to claim 38, wherein:

The low refractive underlayer comprises at least one of silicon oxide and silicon nitride; and is

The low-refractive underlayer has a refractive index greater than that of the low-refractive layer.

40. The optical member of claim 39, wherein the low refractive underlayer comprises:

A first low-refractive bottom layer disposed on the light guide plate; and

A second low refractive index underlayer disposed on the first low refractive index underlayer.

41. The optical member according to claim 40, wherein each of the first low-refractive underlayer and the second low-refractive underlayer has a thickness of 0.2 μm or less.

42. The optical member according to claim 38, wherein:

The low-refraction coating layer comprises at least one of silicon oxide and silicon nitride; and

The low-refractive index covering layer has a refractive index greater than that of the low-refractive index layer.

43. the optical member according to claim 42, wherein the low-refractive cover layer comprises:

A first low-refractive cover layer disposed on the low-refractive layer; and

A second low-refractive cover layer disposed on the first low-refractive cover layer.

44. the optical member according to claim 43, wherein each of the first low-refractive cover layer and the second low-refractive cover layer has a thickness of 0.2 μm or less.

45. The optical member of claim 38, further comprising a wavelength converting cladding layer disposed on the wavelength converting layer,

wherein the wavelength converting cladding layer comprises at least one of silicon oxide and silicon nitride.

46. The optical member of claim 45, wherein the wavelength-converting cladding layer comprises:

A first wavelength converting cladding layer disposed on the wavelength converting layer; and

a second wavelength converting cladding layer disposed on the first wavelength converting cladding layer.

47. the optical member according to claim 46, wherein one of said first and second wavelength converting cladding layers comprises a transparent organic material and the other of said first and second wavelength converting cladding layers comprises at least one of silicon oxide and silicon nitride.

48. The optical member according to claim 47, wherein:

the first wavelength converting cladding layer comprises silicon oxide; and

The second wavelength converting cladding layer includes a transparent organic material.

49. The optical member of claim 46, wherein the wavelength-converting cladding layer further comprises a third wavelength-converting cladding layer disposed on the second wavelength-converting cladding layer.

50. A display, comprising:

An optical member including a light guide plate; a low refractive layer disposed on the light guide plate and having a refractive index less than that of the light guide plate; a low-refractive bottom layer disposed between the low-refractive layer and the light guide plate; and a wavelength conversion layer disposed on the low refractive layer;

A light source disposed on at least one side surface of the light guide plate; and

A display panel disposed on the optical member.

51. The display of claim 50, wherein:

The low refractive underlayer comprises at least one of silicon oxide and silicon nitride; and is

the low-refractive underlayer has a refractive index greater than that of the low-refractive layer.

52. The display of claim 51, wherein:

The low-refractive underlayer includes: a first low-refractive bottom layer disposed on the light guide plate; and

A second low refractive index underlayer disposed on the first low refractive index underlayer.

53. The display of claim 50, further comprising a wavelength converting cladding layer disposed on said wavelength converting layer,

Wherein the wavelength converting cladding layer comprises at least one of silicon oxide and silicon nitride.

54. The display of claim 53, wherein:

The wavelength converting cladding layer includes: a first wavelength converting cladding layer disposed on the wavelength converting layer; and

A second wavelength converting cladding layer disposed on the first wavelength converting cladding layer.

55. The display of claim 54, wherein the wavelength-converting cladding layer further comprises a third wavelength-converting cladding layer disposed on the second wavelength-converting cladding layer.

56. The display of claim 50, wherein said optical member further comprises a low refractive cover layer disposed between said low refractive layer and said wavelength converting layer.

57. The display of claim 56, wherein:

The low-refraction coating layer comprises at least one of silicon oxide and silicon nitride; and

The low-refractive index covering layer has a refractive index greater than that of the low-refractive index layer.

58. The display of claim 57 further comprising a wavelength converting cladding layer disposed on said wavelength converting layer,

wherein the wavelength converting cladding layer comprises at least one of silicon oxide and silicon nitride.

59. A display, comprising:

An optical member including a light guide plate; a low refractive layer disposed on the light guide plate and having a refractive index less than that of the light guide plate; a wavelength conversion layer disposed on the low refractive layer; and a low refractive index covering layer disposed between the low refractive index layer and the wavelength conversion layer;

A light source disposed on at least one side surface of the light guide plate; and

A display panel disposed on the optical member.

60. The display of claim 59, wherein:

The low-refraction coating layer comprises at least one of silicon oxide and silicon nitride; and

The low-refractive index covering layer has a refractive index greater than that of the low-refractive index layer.

61. The display of claim 60, further comprising a wavelength converting cladding layer disposed on said wavelength converting layer,

wherein the wavelength converting cladding layer comprises at least one of silicon oxide and silicon nitride.

Technical Field

exemplary embodiments of the present invention relate generally to an optical member, and more particularly, to a display including the optical member.

Background

the liquid crystal display generally receives light from the backlight assembly and displays an image. Some backlight assemblies include a light source and a light guide plate. The light guide plate may receive light from the light source and guide the light to the display panel. In some products, the light source provides white light, and the white light is filtered by color filters of the display panel to achieve color.

Recently, studies have been made on the application of wavelength conversion films to improve image quality (e.g., color reproducibility of liquid crystal displays). In general, a blue light source is used as the light source, and a wavelength conversion film is disposed on the light guide plate to convert blue light into white light. The wavelength converting film typically includes wavelength converting particles. Since the wavelength converting particles are typically susceptible to moisture, they are protected with a barrier film. However, barrier films are expensive and may increase the overall thickness of the device. In addition, since the wavelength conversion film should be laminated on the light guide plate, a complicated assembly process may be required.

the above information disclosed in the background section is only for background understanding of the inventive concept and, therefore, it may contain information that does not constitute prior art.

Disclosure of Invention

The optical member having a laminated structure and the display device including the same according to the exemplary embodiments of the present invention can provide improved light transmission efficiency.

additional features of the inventive concept will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by the practice of the inventive concept.

The optical member according to an exemplary embodiment includes a light guide plate; a low refractive layer disposed on the light guide plate and having a refractive index less than that of the light guide plate; a low-refractive base layer disposed between the low-refractive layer and the light guide plate and having a thickness less than that of the low-refractive layer; and a wavelength conversion layer disposed on the low refractive layer.

An optical member according to another exemplary embodiment includes a light guide plate; a low refractive layer disposed on the light guide plate and having a refractive index less than that of the light guide plate; a wavelength conversion layer disposed on the low refractive layer; and a low-refractive cover layer disposed between the low-refractive layer and the wavelength conversion layer and having a thickness less than that of the low-refractive layer.

an optical member according to still another exemplary embodiment includes a light guide plate; a low refractive layer disposed on the light guide plate and having a refractive index less than that of the light guide plate; a wavelength conversion layer disposed on the low refractive layer; a low-refraction bottom layer disposed between the low-refraction layer and the light guide plate; and a low-refractive cover layer disposed between the low-refractive layer and the wavelength conversion layer.

a display according to still another example includes an optical member including a light guide plate, a light source, and a display panel; a low refractive layer disposed on the light guide plate and having a refractive index less than that of the light guide plate; a low-refraction bottom layer disposed between the low-refraction layer and the light guide plate; and a wavelength conversion layer disposed on the low refractive layer, the light source being disposed on at least one side surface of the light guide plate, and the display panel being disposed on the optical member.

A display according to still another exemplary embodiment includes an optical member including a light guide plate, a light source, and a display panel; a low refractive layer disposed on the light guide plate and having a refractive index less than that of the light guide plate; a wavelength conversion layer disposed on the low refractive layer; and a low refractive cover layer disposed between the low refractive layer and the wavelength conversion layer, the light source being disposed on at least one side surface of the light guide plate, and the display panel being disposed on the optical member.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.

Drawings

the accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the invention and together with the description serve to explain the inventive concept.

Fig. 1 is a perspective view of an optical member and a light source according to an exemplary embodiment.

Fig. 2 is a sectional view taken along line II-II' in fig. 1.

Fig. 3 and 4 are sectional views of a low refractive layer according to an exemplary embodiment.

Fig. 5A is a table illustrating a wavelength conversion underlayer according to an exemplary embodiment, and fig. 5B is a table illustrating transmittance with respect to silicon nitride (SiN) on a light guide plate_x) A graph of the change in thickness of (a).

Fig. 6A, 6B, 6C, and 6D are tables showing a lamination structure and a thickness for ensuring the maximum transmittance for each case of fig. 5A.

Fig. 7, 8, 9, 10, 11, 12, 13 and 14 are cross-sectional views of a wavelength conversion substrate according to an exemplary embodiment.

fig. 15A is a table illustrating a wavelength conversion capping layer according to an exemplary embodiment, and fig. 15B is a table illustrating transmittance with respect to silicon nitride (SiN) on a wavelength conversion layer_x) A graph of the change in thickness of (a).

Fig. 16A, 16B, and 16C are tables showing a laminated structure and thickness for ensuring the maximum transmittance for each case of fig. 15A.

Fig. 17, 18, 19 and 20 are cross-sectional views of wavelength converting cladding layers according to example embodiments.

Fig. 21, 22 and 23 are sectional views of an optical member according to an exemplary embodiment.

Fig. 24 is a cross-sectional view of a display according to an example embodiment.

Fig. 25 is a cross-sectional view of a display according to an example embodiment.

Detailed Description

In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of various exemplary embodiments or implementations of the present invention. As used herein, "examples" and "embodiments" are interchangeable words, which are non-limiting examples of apparatus or methods that employ one or more of the inventive concepts disclosed herein. It may be evident, however, that the various exemplary embodiments may be practiced without these specific details or with one or more equivalent arrangements. In other instances, well-known structures and devices are shown in block diagram form in order to avoid unnecessarily obscuring the various exemplary embodiments. Moreover, the various exemplary embodiments may be different, but are not necessarily exclusive. For example, particular shapes, configurations and characteristics of exemplary embodiments may be used or implemented in another exemplary embodiment without departing from the inventive concept.

Unless otherwise indicated, the illustrated exemplary embodiments should be understood as providing exemplary features of varying detail of some ways in which the inventive concept may be practiced. Thus, unless otherwise specified, features, components, modules, layers, films, panels, regions, and/or aspects and the like (individually or collectively, "elements" hereinafter) of the various embodiments may be additionally combined, separated, interchanged, and/or rearranged without departing from the inventive concepts.

It is often provided that the boundaries between adjacent elements are clarified using cross-hatching and/or shading in the figures. Thus, unless otherwise specified, the presence or absence of cross-hatching or shading does not convey or indicate any preference or requirement for a particular material, material property, size, proportion, commonality between illustrated elements, and/or any other characteristic, attribute, property, etc. of an element. Further, in the drawings, the size and relative sizes of elements may be exaggerated for clarity and/or description purposes. When the exemplary embodiments may be implemented differently, a specific processing order may be performed differently from the described order. For example, two processes described in succession may be executed substantially concurrently or in the reverse order to that described. Also, like reference numerals denote like elements.

when an element such as a layer is referred to as being "on," "connected to" or "coupled to" another element or layer, it can be directly on, connected or coupled to the other element or layer or intervening elements or layers may be present. However, when an element or layer is referred to as being "directly on," "directly connected to" or "directly coupled to" another element or layer, there are no intervening elements or layers present. For the purposes of this disclosure, the term "connected" may refer to physical, electrical, and/or fluid connections, with or without intervening elements. Further, the D1, D2, and D3 axes are not limited to three axes (e.g., x, y, and z axes) of a rectangular coordinate system and may be construed in a broader sense. For example, the D1, D2, and D3 axes may be perpendicular to each other, or may represent different directions that are not perpendicular to each other. For purposes of this disclosure, "at least one of X, Y and Z" and "at least one selected from the group consisting of X, Y and Z" can be interpreted as X only, Y only, Z only, or any combination of two or more of X, Y and Z, such as, for example, XYZ, XYY, YZ, and ZZ. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

Although the terms first, second, etc. may be used herein to describe various types of elements, these elements should not be limited by these terms. These terms are used to distinguish one element from another. Thus, a first element discussed below could be termed a second element without departing from the teachings of the present disclosure.

Spatially relative terms, such as "below," "lower," "upper," "above," "upper," "higher," "side" (e.g., "sidewall") and the like, may be used herein for descriptive purposes and thus the relationship of one element to another element(s) as illustrated in the figures. Spatially relative terms are intended to encompass different orientations of the device in use, operation, and/or manufacture in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "below" or "beneath" other elements or features would then be oriented "above" the other elements or features. Thus, the exemplary term "below" can include both an orientation of above and below. Further, the device may be otherwise oriented (e.g., rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

The terminology used herein is for the purpose of describing particular embodiments and is not intended to be limiting. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. Furthermore, the terms "comprises," "comprising," "includes" and/or "including," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, components, and/or groups thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. It should also be noted that, as used herein, the terms "substantially," "about," and other similar terms are used as approximations, not terms of degree, and thus, are used to take into account the inherent deviations in measured, calculated, and/or provided values that will be recognized by those of ordinary skill in the art.

Various exemplary embodiments are described herein with reference to cross-sectional and/or exploded views, which are schematic illustrations of idealized exemplary embodiments and/or intermediate structures. Variations from the shapes of the illustrations as a result, for example, of manufacturing techniques and/or tolerances, are to be expected. Thus, example embodiments disclosed herein should not necessarily be construed as limited to the particular illustrated shapes of regions but are to include deviations in shapes that result, for example, from manufacturing. In this manner, the regions illustrated in the figures may be schematic in nature and the shapes of the regions may not reflect the actual shape of a region of a device and are, therefore, not necessarily intended to be limiting.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

Fig. 1 is a perspective view of an optical member 100 and a light source 400 according to an exemplary embodiment. Fig. 2 is a sectional view taken along line II-II' in fig. 1.

Referring to fig. 1 and 2, the optical member 100 may include a light guide plate 10, a wavelength conversion substrate 70 disposed on the light guide plate 10, a wavelength conversion layer 50 disposed on the wavelength conversion substrate 70, and a wavelength conversion cover layer 60 disposed on the wavelength conversion layer 50. The wavelength-converting substrate 70 may include a low-refractive substrate 20, a low-refractive layer 30 disposed on the low-refractive substrate 20, and a low-refractive cover layer 40 disposed on the low-refractive layer 30.

The light guide plate 10 may guide a light path. The light guide plate 10 may generally have a substantially polygonal pillar shape. The planar shape of the light guide plate 10 may be substantially rectangular, but the inventive concept is not limited thereto. In an exemplary embodiment, the light guide plate 10 may have a substantially hexagonal pillar shape having a rectangular planar shape, and may include an upper surface 10a, a lower surface 10b, and four side surfaces 10S1, 10S2, 10S3, and 10S 4. Hereinafter, four side surfaces of the light guide plate 10 will be respectively denoted as 10S1, 10S2, 10S3, and 10S4, and one of the four side surfaces will be generally denoted as 10S.

In an exemplary embodiment, each of the upper surface 10a and the lower surface 10b of the light guide plate 10 may be disposed on a corresponding plane. More specifically, a plane on which the upper surface 10a is disposed may be substantially parallel to a plane on which the lower surface 10b is disposed, so that the total thickness of the light guide plate 10 is uniform. However, the upper surface 10a or the lower surface 10b may be formed of a plurality of planes, or a plane on which the upper surface 10a is provided may intersect with a plane on which the lower surface 10b is provided. For example, the light guide plate 10 may be thinned from one side surface (e.g., a light incident surface) toward the other side surface (e.g., an opposite surface) facing the one side surface, such as a wedge-shaped light guide plate. Alternatively, the lower surface 10b may be inclined upward from one side surface (e.g., a light incident surface) toward the other side surface (e.g., an opposite surface) facing the one side surface up to a predetermined distance, so that the light guide plate 10 is thinned up to the predetermined distance and then has a substantially uniform thickness over the predetermined distance.

in the optical member 100 according to an exemplary embodiment, the light source 400 may be disposed adjacent to at least one side surface 10S of the light guide plate 10. In fig. 1, a plurality of Light Emitting Diode (LED) light sources 410 are mounted on a printed circuit board 420 and disposed adjacent to the side surface 10S1 of the light guide plate 10. However, the inventive concept is not limited thereto, and for example, the LED light source 410 may be disposed adjacent to the side surfaces 10S1 and 10S3 along both long sides, or may be disposed adjacent to the side surfaces 10S2 or 10S4 along one short side, or disposed adjacent to the side surfaces 10S2 and 10S4 at both short sides. As shown in fig. 1, the side surface 10S1 of the light guide plate 10 adjacent to the light source 400 may be a light incident surface to which light of the light source 400 is directly incident, and the side surface 10S3 at the other long side facing the side surface 10S1 may be an opposite surface.

The light guide plate 10 may include an inorganic material. For example, the light guide plate 10 may be made of glass.

The optical interface may be formed at a surface where the layers 20, 30, 40, 50, and 60 of the optical member 100 meet each other. The optical member 100 may include a plurality of optical interfaces 30a, 30b, 50a, and 50 b. Each of the optical interfaces 30a, 30b, 50a, and 50b may be substantially parallel to the upper surface 10a of the light guide plate 10.

The wavelength-converting base layer 70 is disposed on the upper surface 10a of the light guide plate 10. The wavelength-converting substrate 70 may include a low-refractive layer 30, a low-refractive substrate 20, and a low-refractive cover layer 40. The wavelength-converting underlayer 70 may be directly formed on the upper surface 10a of the light guide plate 10 to contact the upper surface 10a of the light guide plate 10. The wavelength conversion underlayer 70 is interposed between the light guide plate 10 and the wavelength conversion layer 50 to contribute to the total reflection of the optical member 100.

More specifically, in order for the light guide plate 10 to effectively guide light from the light incident surface 10S1 to the opposite surface 10S3, effective total internal reflection should occur in the light guide plate 10. One condition under which total internal reflection can occur in the light guide plate 10 is that the refractive index of the light guide plate 10 is greater than the refractive index of the medium that forms the optical interface with the light guide plate 10. When the refractive index of the medium forming the optical interface with the light guide plate 10 is low, the critical angle for total reflection is small, resulting in more total internal reflection.

For example, when the light guide plate 10 is made of glass having a refractive index of about 1.5, sufficient total reflection may occur on the lower surface 10b of the light guide plate 10 because the lower surface 10b is exposed to an air layer having a refractive index of about 1, and thus forms an optical interface with the air layer.

on the other hand, since the other optically functional layers are laminated on the upper surface 10a of the light guide plate 10 as a whole, it may be difficult to achieve sufficient total reflection on the upper surface 10a as compared with the lower surface 10 b. For example, if a material layer having a refractive index of 1.5 or more is laminated on the upper surface 10a of the light guide plate 10, total reflection does not occur on the upper surface 10a of the light guide plate 10. In addition, if a material layer having a refractive index of, for example, about 1.49, which is slightly smaller than the refractive index of the light guide plate 10, is laminated on the upper surface 10a of the light guide plate 10, although total internal reflection may occur on the upper surface 10a of the light guide plate 10, sufficient total reflection may not occur due to an increased critical angle. The wavelength conversion layer 50 laminated on the upper surface 10a of the light guide plate 10 generally has a refractive index of about 1.5. If the wavelength conversion layer 50 is directly laminated on the upper surface 10a of the light guide plate 10, it may be difficult to have sufficient total reflection on the upper surface 10a of the light guide plate 10.

The low refractive layer 30 interposed between the light guide plate 10 and the wavelength conversion layer 50 to form an interface with the upper surface 10a of the light guide plate 10 has a refractive index lower than that of the light guide plate 10, and thus total reflection may occur on the upper surface 10a of the light guide plate 10. In addition, the low refractive layer 30 has a refractive index smaller than that of the wavelength conversion layer 50, and the wavelength conversion layer 50 is a material layer disposed on the low refractive layer 30, so that more total reflection can occur than when the wavelength conversion layer 50 is disposed directly on the upper surface 10a of the light guide plate 10.

When the low refractive index underlayer 20 is disposed on the light guide plate 10, total reflection may also occur at the interface between the light guide plate 10 and the low refractive index underlayer 20 due to the difference in refractive index between the light guide plate 10 and the low refractive index underlayer 20. However, light incident on the interface at an angle smaller than the critical angle of total reflection may travel toward the low refractive underlayer 20. Then, the light may be reflected or refracted again at the interface between the low refractive underlayer 20 and the low refractive layer 30. When the refractive index of the low refractive layer 30 is smaller than that of the low refractive underlayer 20, total reflection may also occur at the interface. When the optical member 100 includes the low refractive index base layer 20, the low refractive index base layer 20 is interposed between the light guide plate 10 and the low refractive index layer 30. However, the difference in refractive index between the light guide plate 10 and the low refractive layer 30 ultimately determines the critical angle of total reflection. Since the refractive index difference increases as the refractive index of the low refractive layer 30 becomes smaller, the critical angle for total reflection may become smaller, resulting in more total reflection.

The wavelength conversion substrate 70 interposed between the light guide plate 10 and the wavelength conversion layer 50 to form an interface with the upper surface 10a of the light guide plate 10 may include the low refractive layer 30. The low refractive layer 30 has a refractive index smaller than that of the light guide plate 10 so that total reflection may occur on the lower surface 30b of the low refractive layer 30. Further, the low refractive layer 30 has a refractive index smaller than that of the wavelength conversion layer 50, and the wavelength conversion layer 50 is a material layer disposed on the low refractive layer 30, so that more total reflection may occur than when the wavelength conversion layer 50 is disposed directly on the upper surface 10a of the light guide plate 10.

The difference between the refractive index of the light guide plate 10 and the refractive index of the low refractive layer 30 may be 0.2 or more. When the refractive index of the low refractive layer 30 is smaller than that of the light guide plate 10 by 0.2 or more, sufficient total reflection may occur on the lower surface 30b of the low refractive layer 30. There is no upper limit to the difference between the refractive index of the light guide plate 10 and the refractive index of the low refractive layer 30. However, the difference between the refractive index of the light guide plate 10 and the refractive index of the low refractive layer 30 may be 1 or less in consideration of the typical material of the light guide plate 10 and the typical refractive index of the low refractive layer 30. The refractive index of the low refractive layer 30 may be in the range of 1.2 to 1.4. Generally, as the refractive index of a solid medium becomes close to 1, the manufacturing cost increases exponentially. When the refractive index of the low refractive layer 30 is 1.2 or more, an excessive increase in manufacturing cost can be prevented. In addition, the low refractive layer 30 having a refractive index of 1.4 or less is advantageous in sufficiently reducing the critical angle of total reflection of the upper surface 10a of the light guide plate 10. In an exemplary embodiment, a low refractive layer 30 having a refractive index of about 1.25 may be applied.

In order to have the above-described low refractive index, the low refractive layer 30 may include voids. The voids may be made of vacuum or may be filled with an air layer, gas, or the like. The void space may be defined by particles or a matrix, which will be described in more detail below with reference to fig. 3 and 4.

Fig. 3 and 4 are sectional views of a low refractive layer according to an exemplary embodiment.

In an exemplary embodiment, the low refractive layer 30 may include a plurality of particles PT, a matrix MX surrounding the particles PT and formed as a single sheet, and a plurality of voids VD, as shown in fig. 3. The particles PT may be a filler for adjusting the refractive index and mechanical strength of the low refractive layer 30.

The particles PT may be dispersed within the matrix MX of the low refractive layer 30, and the voids VD may be formed in the open portions of the matrix MX. For example, after the particles PT and the matrix MX are mixed in the solvent, and when the mixture is dried and/or solidified, the solvent may be evaporated. At this time, the void VD may be formed between the portions of the matrix MX.

In an exemplary embodiment, the low refractive layer 30 may include the matrix MX and the voids VD without particles, as shown in fig. 4. For example, the low refractive layer 30 may include a matrix MX (such as a foamed resin) formed as a single sheet, and a plurality of voids VD disposed in the matrix MX.

When the low refractive layer 30 includes the voids VD, as shown in fig. 3 and 4, the overall refractive index of the low refractive layer 30 may have a value between the refractive index of the particles PT/matrix MX and the refractive index of the voids VD. When the voids VD are filled with a vacuum having a refractive index of 1, or an air layer or a gas having a refractive index of about 1, the total refractive index of the low-refractive layer 30 may have a value of 1.4 or less, for example, about 1.25, even if a material having a refractive index of 1.4 or more is used as the particles PT/matrix MX. In an exemplary embodiment, the particles PT may be made of an inorganic material (e.g. SiO)₂、Fe₂O₃Or MgF₂) And the matrix MX can be made of organic material (for example polysiloxane). However, the inventive concept is not limited thereto, and other organic materials orAn inorganic material.

Referring back to fig. 1 and 2, the low refractive layer 30 may have a thickness of 0.4 μm to 2 μm. When the thickness of the low refractive layer 30 is 0.4 μm or more, which is a visible light wavelength range, the low refractive layer 30 can form an effective optical interface. Therefore, the total reflection according to Snell's law can well occur on the lower surface 30b of the low refractive layer 30. Too thick low refractive layer 30 may be disadvantageous for thinning of optical member 100, increase material cost, and destroy luminescence of optical member 100. Accordingly, the low refractive layer 30 may be formed to have a thickness of 2 μm or less. In an exemplary embodiment, the thickness of the low refractive layer 30 may be about 1 μm.

The low refractive index underlayer 20 may be disposed between the light guide plate 10 and the low refractive index layer 30. The low refractive index underlayer 20 may be directly formed on the upper surface 10a of the light guide plate 10 to contact the upper surface 10a of the light guide plate 10. In addition, the low refractive index underlayer 20 may contact the lower surface 30b of the low refractive index layer 30. The low refractive index underlayer 20 may be interposed between the light guide plate 10 and the low refractive index layer 30. The refractive index of the low-refractive index underlayer 20 may be greater than that of the low-refractive index layer 30. The low refractive index underlayer 20 may have a single layer structure, and include any one of a low refractive index material and a high refractive index material. Alternatively, the low refractive index underlayer 20 may have a multi-layer structure in which a low refractive index material and a high refractive index material are alternately laminated. The refractive index of the low refractive material may be 1.3 to 1.7. The refractive index of the high refractive material may be 1.5 to 2.2. In an exemplary embodiment, the low refractive material may be silicon oxide (SiO)_x) And the high refractive material may be silicon nitride (SiN)_x). However, the low refractive material and the high refractive material may be various other materials satisfying the above refractive index.

since the influence of constructive or destructive interference of light varies according to the laminate material and the laminate thickness of the low refractive index bottom layer 20, the light transmittance may be changed. That is, the light transmittance can be adjusted by controlling the laminate material and the laminate thickness of the low refractive index base layer 20. In addition, when the low refractive index underlayer 20 includes an inorganic layer, the inorganic layer may serve as a protective layer to prevent moisture/oxygen from penetrating into the low refractive index layer 30.

The low refractive index cover layer 40 may be disposed between the low refractive layer 30 and the wavelength conversion layer 50. The low refractive index cover layer 40 may be directly formed on the upper surface of the low refractive index layer 30 to contact the upper surface of the low refractive index layer 30. In addition, the low refractive index cover layer 40 may contact the lower surface of the wavelength conversion layer 50. The low refractive index cover layer 40 may be interposed between the low refractive layer 30 and the wavelength conversion layer 50. The low-refractive index cover layer 40 may have a refractive index greater than that of the low-refractive layer 30. The low-refractive cover layer 40 helps to induce total reflection from the upper surface of the low-refractive layer 30 toward the wavelength conversion layer 50. The low-refractive cover layer 40 may have a single-layer structure including any one of a low-refractive material and a high-refractive material. Alternatively, the low-refractive cover layer 40 may have a multi-layered structure in which a low-refractive material and a high-refractive material are alternately laminated. As in the low-refractive index underlayer 20, the refractive index of the low-refractive material may be 1.2 to 1.7. The refractive index of the high refractive material may be 1.5 to 2.2. In an exemplary embodiment, the low refractive material may be silicon oxide (SiO)_x) And the high refractive material may be silicon nitride (SiN)_x). However, the low-refractive material and the high-refractive material may include various other materials satisfying the above refractive index.

Since the influence of the constructive or destructive interference of light varies according to the laminate material and the laminate thickness of the low-refractive cover layer 40, the light transmittance may vary. That is, the light transmittance may be adjusted by controlling the laminate material and the laminate thickness of the low-refractive cover layer 40. In addition, the low-refractive cover layer 40 may improve the optical efficiency of the optical member 100. When light transmitted through the low refractive layer 30 enters the wavelength conversion layer 50 and encounters the dispersed scattering particles, the light is scattered as the wavelength thereof is changed. Here, part of the scattered light may return toward the light guide plate 10. If the low-refractive cover layer 40 has a refractive index higher than that of the low-refractive layer 30, light may be totally reflected at the interface between the low-refractive cover layer 40 and the low-refractive layer 30 and may be reflected back upward, thereby improving the optical efficiency, e.g., brightness, of the display.

the low refractive index cover layer 40 may completely overlap the low refractive index layer 30 to prevent moisture and/or oxygen from penetrating into the low refractive index layer 30. That is, the low refractive index cover layer 40 may prevent deformation of the low refractive index layer 30 and ensure structural stability by increasing hardness. In addition, the low-refractive cover layer 40 including the inorganic layer may prevent moisture and/or oxygen from penetrating into the wavelength conversion layer 50 disposed on the low-refractive cover layer 40 and the low-refractive layer 30 disposed under the low-refractive cover layer 40.

The wavelength conversion underlayer 70 may be formed by methods such as deposition and coating. The wavelength-converting substrate 70 may be formed on the light guide plate 10 in the order of the low-refractive substrate 20, the low-refractive layer 30, and the low-refractive cover layer 40. In an exemplary embodiment, the low-refractive underlayer 20 and the low-refractive cover layer 40 may be formed of an inorganic layer including an inorganic material by using a chemical vapor deposition method. The low refractive layer 30 may be formed of an organic layer including an organic material by using a coating method. Examples of coating methods include slot coating, spin coating, roll coating, spray coating, and inkjet. However, the inventive concept is not limited to a specific coating method, and various other lamination methods may be applied.

The wavelength conversion layer 50 is disposed on the wavelength conversion underlayer 70. In an exemplary embodiment, when the wavelength conversion substrate 70 includes the low refractive cover layer 40, the wavelength conversion layer 50 may be disposed on an upper surface of the low refractive cover layer 40. In an exemplary embodiment, when the wavelength conversion base layer 70 does not include the low refractive cover layer 40, the wavelength conversion layer 50 may be disposed on the upper surface of the low refractive layer 30. The wavelength conversion layer 50 may include an adhesive layer and wavelength conversion particles dispersed in the adhesive layer. The wavelength conversion layer 50 may further include scattering particles dispersed in the adhesive layer in addition to the wavelength conversion particles.

The adhesive layer is a medium to which the wavelength converting particles are dispersed, and may be made of various resin compositions generally called adhesives. However, the inventive concept is not limited thereto, and any medium into which the wavelength conversion particles and/or the scattering particles may be dispersed may be referred to as an adhesive layer regardless of its name, additional other functions, constituent materials, and the like.

The wavelength converting particles are particles that convert the wavelength of incident light. For example, the wavelength converting particles may be quantum dots, fluorescent materials, or phosphorescent materials. In particular, quantum dots, which are an example of wavelength converting particles, are materials having a crystal structure of several nanometers in size. Quantum dots are composed of hundreds to thousands of atoms and exhibit a quantum confinement effect in which the energy band gap is increased due to the small size of the quantum dots. When light having a wavelength higher than the band gap is incident on the quantum dot, the quantum dot becomes an excited state by absorbing light, and falls to a ground state while emitting light of a specific wavelength. The emitted light of a particular wavelength has a value corresponding to the band gap. By controlling the size and composition of the quantum dots, the luminescent properties of the quantum dots from quantum confinement effects can be tuned.

The quantum dots may include at least one of group II-VI compounds, group II-V compounds, group III-VI compounds, group III-V compounds, group IV-VI compounds, group I-III-VI compounds, group II-IV-VI compounds, and group II-IV-V compounds.

The quantum dot may include a core and a shell covering the core. The core may be, but is not limited to, for example, CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InP, InAs, InSb, SiC, Ca, Se, In, P, Fe, Pt, Ni, Co, Al, Ag, Au, Cu, FePt, Fe₂O₃、Fe₃O₄At least one of Si and Ge. The shell may include, but is not limited to, for example, at least one of ZnS, ZnSe, ZnTe, CdS, CdSe, CdTe, HgS, HgSe, HgTe, AlN, AlP, AlAs, AlSb, GaN, GaP, GaAs, GaSb, GaSe, InN, InP, InAs, InSb, TlN, TlP, TlAs, TlSb, PbS, PbSe, and PbTe.

The wavelength converting particles may include a plurality of wavelength converting particles that convert incident light into light having different wavelengths. For example, the wavelength converting particles may include first wavelength converting particles that convert incident light of a specific wavelength into light of a first wavelength and emit the light of the first wavelength, and second wavelength converting particles that convert incident light of a specific wavelength into light of a second wavelength and emit the light of the second wavelength. In an exemplary embodiment, the light emitted from the light source 400 and then incident on the wavelength conversion particles may be light of a blue wavelength, the first wavelength may be a green wavelength, and the second wavelength may be a red wavelength. For example, the blue wavelength may be a wavelength having a peak of 420 to 470nm, the green wavelength may be a wavelength having a peak of 520 to 570nm, and the red wavelength may be a wavelength having a peak of 620 to 670 nm. However, the inventive concept is not limited thereto, and all wavelength ranges that can be recognized as blue, green, and red may be used.

In the above-described exemplary embodiment, when blue light incident on the wavelength conversion layer 50 passes through the wavelength conversion layer 50, a portion of the blue light may be incident on the first wavelength conversion particles to be converted into green wavelengths and emitted as light of green wavelengths, another portion of the blue light may be incident on the second wavelength conversion particles to be converted into red wavelengths and emitted as light of red wavelengths, and the remaining portion of the blue light may be emitted because it does not enter the first and second wavelength conversion particles. Therefore, the light that has passed through the wavelength conversion layer 50 includes all of light of blue wavelength, light of green wavelength, and light of red wavelength. White light or other colored emitted light can be displayed if the ratio of emitted light of different wavelengths is appropriately adjusted. The light converted by the wavelength conversion layer 50 is concentrated in a narrow specific wavelength range and has a sharp spectrum with a narrow half width. Therefore, when light of such a spectrum is filtered using a color filter to realize colors, color reproducibility can be improved.

Unlike the above-described exemplary embodiment, the incident light may be light having a short wavelength, for example, ultraviolet light, and three types of wavelength conversion particles for converting the incident light into blue, green, and red wavelengths may be provided in the wavelength conversion layer 50 to emit white light.

The wavelength conversion layer 50 may also include scattering particles. The scattering particles may be non-quantum dot particles without wavelength conversion functionality. The scattering particles may scatter incident light such that more incident light enters the wavelength converting particles. In addition, the scattering particles can uniformly control the output angle of light of each wavelength. Specifically, a portion of incident light that enters the wavelength converting particles is wavelength converted at its wavelength by the wavelength converting particlesWhen emitted after particle conversion, the emission direction of the portion of the incident light has random scattering properties. If there are no scattering particles in the wavelength conversion layer 50, the green and red wavelengths emitted after collision with the wavelength conversion particles may have a scattering emission characteristic, but the blue wavelength emitted without collision with the wavelength conversion particles may not have a scattering emission characteristic. Therefore, the emission amount of blue/green/red wavelengths may vary according to the output angle. The scattering particles may even provide a scattering luminescence property for blue wavelengths emitted without colliding with the wavelength converting particles, thereby controlling the output angle of light of each wavelength to be similar. The scattering particles may be made of TiO₂Or SiO₂and (4) preparing.

The wavelength conversion layer 50 may be thicker than the low refractive layer 30. The thickness of the wavelength conversion layer 50 may be about 10 μm to 50 μm. In an exemplary embodiment, the thickness of the wavelength conversion layer 50 may be about 10 μm.

The wavelength conversion layer 50 may be formed by a method such as coating. For example, the wavelength conversion layer 50 may be formed by: the wavelength conversion composition is slot-coated on the light guide plate 10 having the wavelength conversion bottom layer 70, and the wavelength conversion composition is dried and cured. However, the inventive concept is not limited to a specific method of forming the wavelength conversion layer 50, and various other lamination methods may be applied.

a wavelength converting cladding layer 60 may be disposed on the wavelength converting layer 50. The wavelength conversion coating 60 may be a passivation layer that prevents moisture and/or oxygen (hereinafter, referred to as "moisture/oxygen") from permeating. The wavelength converting cladding layer 60 may comprise a plurality of laminated layers. Each laminate layer may comprise an inorganic layer or an organic layer. The wavelength converting cladding layer 60 may include at least one inorganic layer. That is, the wavelength-converting overlay layer 60 may include a single inorganic layer, a plurality of inorganic layers, or a laminated organic layer and inorganic layer.

Each laminated layer may include a high refractive material, a low refractive material, and/or a transparent organic material. The wavelength-converting cladding layer 60 may have a single-layer structure including a low refractive material, a high refractive material, or a transparent organic material, or may have a multi-layer structure having a non-refractive material thereinMaterials of the same refractive index are laminated. In an exemplary embodiment, the high refractive material and the low refractive material may be silicon nitride, aluminum nitride, zirconium nitride, titanium nitride, hafnium nitride, tantalum nitride, silicon oxide, aluminum oxide, titanium oxide, tin oxide, cerium oxide, or silicon oxynitride. In an exemplary embodiment, the high refractive material may be silicon nitride (SiN)_x) And the low refractive material may be silicon oxide (SiO)_x). The transparent organic material may be a silicone resin, an acrylic resin, or an epoxy resin.

The wavelength conversion coating 60 may completely overlap the wavelength conversion layer 50 and cover the upper surface of the wavelength conversion layer 50. In an exemplary embodiment, the wavelength conversion coating layer 60 may cover only the upper surface of the wavelength conversion layer 50. However, in an exemplary embodiment, the wavelength conversion coating layer 60 may further extend outward so as to cover the side surfaces of the wavelength conversion layer 50 and the side surfaces of the wavelength conversion underlayer 70.

The thickness of the wavelength converting cladding layer 60 may be 0.1 μm to 5 μm. In an exemplary embodiment, when the wavelength conversion coating layer 60 does not include an organic layer, the thickness of the wavelength conversion coating layer 60 may be 0.15 μm to 0.5 μm. In an exemplary embodiment, when the wavelength conversion coating layer 60 includes an organic layer, the thickness of the wavelength conversion coating layer 60 may be 1 μm to 5 μm. The thickness of the wavelength converting cladding layer 60 may be less than the thickness of the wavelength converting layer 50. If the thickness of the wavelength-converting cladding layer 60 is 0.1 μm or more, the wavelength-converting cladding layer 60 may exert a significant moisture/oxygen permeation prevention function. The wavelength conversion coating 60 having a thickness of 2 μm or less is advantageous in terms of thinning and transmittance. However, the inventive concept is not limited to a specific thickness of the wavelength-converting cladding layer 60, and the wavelength-converting cladding layer 60 may have various thicknesses. The refractive index and thickness of the laminate of the wavelength converting overlay layer 60 may affect the amount of light extracted through the upper surface, i.e., the transmittance. This will be described in detail later.

The wavelength converting cladding layer 60 may be formed by methods such as coating and deposition. For example, the wavelength conversion underlayer 70 and the wavelength conversion layer 50 may be sequentially formed on the light guide plate 10 by forming an inorganic layer including an inorganic material on the light guide plate 10 using a chemical vapor deposition method. An organic layer including an organic material may be formed on the light guide plate 10 by a coating method. However, the inventive concept is not limited to a specific method of forming the wavelength-converting cladding layer 60, and various other lamination methods may be applied.

As described above, the optical member 100 may simultaneously perform the light guiding function and the wavelength converting function. The optical member 100 may include a wavelength conversion underlayer 70 and a wavelength conversion overlayer 60. The wavelength-converting substrate 70 may include a low-refractive layer 30, a low-refractive substrate 20, and a low-refractive cover layer 40. The low-refractive base layer 20 and the low-refractive cover layer 40 may include a material having a refractive index higher than that of the low-refractive layer 30. Since the low-refractive base layer 20 and the low-refractive cover layer 40 change the influence of constructive or destructive interference of light incident on the optical member 100, they may improve light transmittance. The wavelength-converting cladding layer 60 may include a layer made of at least one of a high refractive material and a low refractive material. In addition, the wavelength-converting cladding layer 60 may be a multilayer further including a transparent organic material. The wavelength conversion coating 60 completely covers the wavelength conversion layer 50 to prevent penetration of moisture/oxygen. In addition, the wavelength conversion coating layer 60 allows the light transmitted through the wavelength conversion layer 50 to be efficiently output to the outside of the optical member 100, thereby improving optical efficiency.

In addition, the wavelength-converting cladding layer 60 provided on the wavelength converting layer 50 of the optical member 100 can reduce the manufacturing cost and reduce the thickness, as compared to a wavelength converting film provided as a separate film. For example, the wavelength conversion film includes barrier films attached to the upper and lower surfaces of the wavelength conversion layer 50. The barrier film is not only expensive but also has a thickness of 100 μm or more. Therefore, the total thickness of the wavelength conversion film may be about 270 μm. On the other hand, the total thickness of the optical member 100 according to the exemplary embodiment excluding the light guide plate 10 may be maintained at about 12 to 13 μm. Therefore, the thickness of a display employing the optical member 100 can be reduced. In addition, since an expensive barrier film may be omitted from the optical member 100, the manufacturing cost may be controlled to a level lower than when a wavelength conversion film is used.

The laminated structure and thickness of the wavelength conversion underlayer 70 for obtaining the maximum light transmittance will now be described. When light passes through media having different refractive indices, reflection and refraction of the light occur at points where the media having different refractive indices meet. If the refractive index and thickness of the medium can be identified, the transmittance of the laminated structure can be obtained using the Fresnel equation relating to the reflection and refraction of light. That is, a simulation for obtaining the transmittance according to the laminated structure and thickness of the wavelength conversion underlayer 70 may be performed.

Fig. 5A is a table illustrating a wavelength conversion underlayer according to an example embodiment. FIG. 5B is a graph showing transmittance versus silicon nitride (SiN) on a light guide plate_x) A graph of the change in thickness of (a). Fig. 6A to 6D are tables showing a laminated structure and thickness that ensure maximum transmittance in each laminated case of the wavelength converting underlayer of fig. 5A.

Fig. 5A is a table showing conditions for performing a simulation. In fig. 5A, a case where each of the low-refractive base layer and the low-refractive cover layer has two layers will be described as an example. When the low-refractive base layer and the low-refractive cover layer are omitted or only one of them is provided, the omitted layer or layers will be represented as having a thickness of 0 μm.

Referring to fig. 2 and 5A, a wavelength-converting substrate 70 is laminated on a light guide plate 10 in the order of a low-refractive substrate 20, a low-refractive layer 30, and a low-refractive cover layer 40. The wavelength conversion underlayer 70 may be interposed between the light guide plate 10 and the wavelength conversion layer 50. The low-refractive base layer 20 and the low-refractive cover layer 40 may each include two or less layers.

Under simulated conditions, the thickness of each layer was selected in the range of 0 μm to 0.2 μm. As described above, a thickness of 0 μm means that the corresponding layer is not included. The thickness of the low refractive layer 30 was set to 1 μm under the simulation conditions. The layers included in the low-refractive base layer 20 and the low-refractive cover layer 40 may be made of a high-refractive material and a low-refractive material. In an exemplary embodiment, the high refractive material may be silicon nitride (SiN)_x) And the low refractive material may be silicon oxide (SiO)_x). The high refractive material will be described hereinafter as silicon nitride (SiN)_x) And the low refractive material will hereinafter be described as silicon oxide (SiO)_x). The layer including the high refractive material and the layer including the low refractive material may be alternately laminated. The refractive indices of the high-refractive material and the low-refractive material may be greater than that of the low-refractive layer 30. The conditions for obtaining the light transmittance of the wavelength conversion underlayer 70 can be divided into four conditions according to the laminate structure.

Referring to fig. 5A, the wavelength conversion base layer of case 1 includes a low refractive base layer 20 laminated on the light guide plate in the order of a high refractive material and a low refractive material, and a low refractive cover layer 40 laminated on the low refractive layer in the order of a high refractive material and a low refractive material.

The wavelength conversion base layer of case 2 includes a low-refractive base layer 20 laminated on the light guide plate in the order of a low-refractive material and a high-refractive material, and a low-refractive cover layer 40 laminated on the low-refractive layer in the order of a high-refractive material and a low-refractive material.

The wavelength-converting base layer of case 3 includes a low-refractive base layer 20 laminated on the light guide plate in the order of a high-refractive material and a low-refractive material, and a low-refractive cover layer 40 laminated on the low-refractive layer in the order of a low-refractive material and a high-refractive material.

The wavelength conversion base layer of case 4 includes a low-refractive base layer 20 laminated on the light guide plate in the order of a low-refractive material and a high-refractive material, and a low-refractive cover layer 40 laminated on the low-refractive layer in the order of a low-refractive material and a high-refractive material.

fig. 5B is a silicon nitride (SiN) showing a low refractive underlayer provided on a light guide plate according to case 1_x) Graph of the change in transmittance for each lamination condition of thickness. Fig. 5B is an example of the simulation result, and the transmittance of the wavelength conversion underlayer of the laminated structure having other cases can also be obtained in the same manner as in fig. 5B. Here, the transmittance means a ratio of blue light transmitted through the lower wavelength conversion underlayer to blue light incident from the light source. In the graph of FIG. 5B, silicon nitride (SiN)_x) Refers to a high refractive material, and silicon oxide (SiO)_x) Refers to a low refractive material.

Refer to FIGS. 2 and 2Fig. 5B, the wavelength conversion substrate 70 on which the simulation of fig. 5B is performed has the structure of case 1 described above. The wavelength converting underlayer 70 of case 1 comprises silicon nitride (SiN)_x) And silicon oxide (SiO)_x) A low refractive index underlayer 20 laminated in this order, and silicon nitride (SiN)_x) And silicon oxide (SiO)_x) A low refractive index cover layer 40 laminated in this order. Silicon nitride (SiN) of low refractive underlayer 20_x) Silicon nitride (SiN) corresponding to the X-axis of the graph of FIG. 5B_x) And (4) thickness. That is, in the graph, the silicon nitride (SiN) of the low refractive underlayer 20_x) Has a variable value, and the low refractive index underlayer 20 is a silicon oxide (SiO)_x) And the silicon nitride (SiN) of the low-refractive cap layer 40_x) And silicon oxide (SiO)_x) Has a specified value. Fig. 5B shows three graphs G1, G2, and G3, which show the silicon oxide (SiO) when the low refractive underlayer 20_x) Has a transmittance with respect to that of the silicon nitride (SiN) of the low refractive index underlayer 20 at thicknesses of 0.06. mu.m, 0.08. mu.m and 0.2. mu.m, respectively_x) The change in thickness. Here, the silicon nitride (SiN) of the low-refractive cap layer 40_x) And silicon oxide (SiO)_x) Are all 0 μm, indicating that the wavelength converting underlayer 70 does not include the low refractive cover layer 40.

G1 is a silicon oxide (SiO) film showing the refractive index of the low refractive index underlayer 20_x) A graph of the change in transmittance at a thickness of 0.06. mu.m. G2 is a silicon oxide (SiO) film showing the refractive index of the low refractive index underlayer 20_x) A graph of the change in transmittance at a thickness of 0.08. mu.m. G3 is a silicon oxide (SiO) film showing the refractive index of the low refractive index underlayer 20_x) A graph of the change in transmittance at a thickness of 0.2 μm. When the silicon nitride (SiN) of the low refractive bottom layer 20_x) At a thickness of about 0.1 μm, G1 had the greatest transmission. When the silicon nitride (SiN) of the low refractive bottom layer 20_x) G2 has maximum transmission at a thickness of about 0.02 μm or about 0.14 μm. When the silicon nitride (SiN) of the low refractive bottom layer 20_x) At a thickness of about 0.1 μm, G3 had the greatest transmission. That is, when the lamination structure (e.g., lamination order and lamination thickness) is changed, the transmittance also changes. Thus, the maximum transmittance under each lamination condition can be identified,And thus, each lamination condition having the maximum transmittance can be determined.

Fig. 6A to 6D are tables showing the lamination structure and thickness that ensure the maximum blue light transmittance in each lamination of the wavelength conversion base layer. In fig. 6A to 6D, three resulting values with high transmittance are shown for each lamination case. The glass of 1.5T means that the light guide plate has a thickness of 1.5 mm. The result value is the result of simulation performed in the case where the low refractive layer is 1 μm and the wavelength conversion layer is 10 μm. In fig. 6A to 6D, silicon oxide (SiO)_x) Is an example of a low refractive material, and silicon nitride (SiN)_x) Is an example of a high refractive material.

Referring to fig. 2 and 6A, result 3 of case 1 is a result value according to G1 described in fig. 5B. Result 3 of case 1 shows that the low refractive underlayer 20 is included and that silicon nitride (SiN) is included_x) And silicon oxide (SiO)_x) The transmittance of the wavelength conversion substrate 70 of the low refractive index covering layer 40 is 0 μm, and in the low refractive index substrate 20, 0.1 μm of silicon nitride (SiN)_x) And 0.06 μm silicon oxide (SiO)_x) Are sequentially laminated on the light guide plate, that is, the low refractive cover layer 40 is not included. The wavelength converting underlayer 70 of result 3 had a blue light transmittance of 81.3%. If the maximum blue light transmittance in each case is obtained as such, all four cases may have a maximum transmittance of about 81.4%. A laminated structure of a wavelength conversion substrate according to various exemplary embodiments will now be described in detail with reference to fig. 7 to 14.

Fig. 7 to 14 are cross-sectional views of wavelength conversion underlayers 71 to 78 according to exemplary embodiments. Fig. 7 to 14 show that the elements of the wavelength converting underlayer may be arranged differently. The wavelength-converting underlayers 71 to 78 may each include the low refractive layer 30, and may further include the low refractive underlayer 20 (see fig. 2) and the low refractive cover layer 40 (see fig. 2). In some exemplary embodiments, the wavelength converting underlayer does not include a low refractive underlayer or a low refractive cover layer. However, in order to efficiently cause total reflection and improve light transmittance, the wavelength conversion substrates 71 to 78 may each include ones of the low-refractive substrate 20 (see fig. 2) and the low-refractive cover layer 40 (see fig. 2)One less. The low-refractive base layer 20 (see fig. 2) and the low-refractive cover layer 40 (see fig. 2) may have a single-layer structure or a multi-layer structure in which a high-refractive material and a low-refractive material are alternately laminated. Silicon nitride (SiN)_x) Will be described hereinafter as an example of a high refractive material, and silicon oxide (SiO)_x) Will be described hereinafter as an example of the low refractive material. However, the inventive concept is not limited to the above examples.

in fig. 7, the low-refractive underlayer 21 and the low-refractive cover layer 41 of the wavelength conversion underlayer 71 have a single-layer structure. The wavelength conversion underlayer 71 of fig. 7 is a structure corresponding to result 2 of case 2 in fig. 6B. That is, in the wavelength converting substrate 71 of fig. 7, the low-refractive substrate 21 is a single layer made of a high-refractive material, and the low-refractive cover layer 41 is a single layer made of a low-refractive material. In an exemplary embodiment, the low refractive underlayer 21 is made of silicon nitride (SiN)_x) Made and having a thickness of 0.06 μm. The low-refractive coating 41 is made of silicon oxide (SiO)_x) Made and having a thickness of 0.1 μm. The blue light transmittance of the wavelength conversion underlayer 71 according to the illustrated exemplary embodiment is 81.3%.

In fig. 8, the low-refractive base layers 22a and 22b of the wavelength converting base layer 72 include alternately laminated materials having different refractive indices, and the low-refractive cover layer 42 is a single-layer structure. The wavelength conversion underlayer 72 of fig. 8 is a structure corresponding to results 1 and 2 of case 1 in fig. 6A. That is, in the wavelength-converting substrate 72 of fig. 8, the low-refractive substrates 22a and 22b may be a multilayer including the first and second low-refractive substrates 22a and 22b having different refractive indexes, and the low-refractive cover layer 42 may be a single layer of a low-refractive material. The refractive index of the first low-refractive underlayer 22a may be greater than that of the second low-refractive underlayer 22 b. The second low-refractive base layer 22b may include the same material as the low-refractive cover layer 42. In an exemplary embodiment, the first low refractive underlayer 22a is made of silicon nitride (SiN)_x) Made and having a thickness of 0.02 μm. The second low-refractive bottom layer 22b is made of silicon oxide (SiO)_x) Made and having a thickness of 0.06 μm. The low-refractive index coating 42 is made of silicon oxide (SiO)_x) Is made ofHaving a thickness of 0.04 μm, silicon oxide (SiO)_x) Is a low refractive material. Thus, the blue light transmittance of the wavelength conversion underlayer 72 was 81.4%. The wavelength converting underlayer 72 according to the exemplary embodiment is the same as the wavelength converting underlayer 72 of the above-described exemplary embodiment in terms of the laminate material, but the thickness of each layer is different. The thickness of the first low-refractive underlayer 22a is 0.02 μm. The thickness of the second low-refractive underlayer 22b was 0.08 μm. The thickness of the low-refractive index coating layer 42 was 0.14 μm. Thus, the blue light transmittance of the wavelength conversion underlayer 72 was 81.4%.

in fig. 9, the low-refractive base layers 23a and 23b of the wavelength converting base layer 73 include alternately laminated materials having different refractive indexes, and the low-refractive cover layer 43 has a single-layer structure. The wavelength conversion underlayer 73 of fig. 9 is a structure corresponding to results 1 and 3 of case 2 in fig. 6B. That is, in the wavelength-converting substrate 73 of fig. 9, the low-refractive substrates 23a and 23b may be a multilayer including the first and second low-refractive substrates 23a and 23b having different refractive indexes, and the low-refractive cover layer 43 may be a single layer of a low-refractive material. The wavelength converting underlayer 73 of fig. 9 may include the same number of layers as in fig. 8. However, in the exemplary embodiment shown in fig. 9, the refractive index of the first low-refractive underlayer 23a may be smaller than the refractive index of the second low-refractive underlayer 23 b. In addition, the first low-refractive base layer 23a may include the same material as the low-refractive cover layer 43. In an exemplary embodiment, the first low refractive underlayer 23a is made of silicon oxide (SiO)_x) Made and having a thickness of 0.06 μm. The second low-refraction bottom layer 23b is made of silicon nitride (SiN)_x) Made and having a thickness of 0.08 μm. The low-refractive coating layer 43 is made of silicon oxide (SiO)_x) Made and having a thickness of 0.02 μm. Thus, the blue light transmittance of the wavelength conversion underlayer 73 is 81.4%. The wavelength converting underlayer 73 according to the exemplary embodiment is the same as the wavelength converting underlayer 73 of the above-described exemplary embodiment in terms of the laminate material, but the thickness of each layer is different. The thickness of the first low-refractive underlayer 23a is 0.04 μm. The thickness of the second low-refractive underlayer 23b was 0.08 μm. The thickness of the low-refractive index covering layer 43 was 0.02 μm. Thus, the blue light transmittance of the wavelength conversion underlayer 73 is 81.3%.

In fig. 10, the wavelength converting underlayer 74 does not include a low-refractive underlayer, and the low-refractive cover layers 44a and 44b have a multilayer structure. The wavelength conversion underlayer 74 of fig. 10 is a structure corresponding to result 3 of case 4 in fig. 6D. That is, in the wavelength converting underlayer 74 of fig. 10, a low-refractive underlayer is not provided, that is, the low-refractive underlayer has a thickness of 0 μm, and the low-refractive cladding layers 44a and 44b may be a multilayer including the first low-refractive cladding layer 44a and the second low-refractive cladding layer 44b having different refractive indices. The refractive index of the first low-refractive cover layer 44a may be smaller than that of the second low-refractive cover layer 44 b. In an exemplary embodiment, the first low-refractive covering layer 44a is made of silicon oxide (SiO)_x) Made and having a thickness of 0.06 μm. The second low-refractive capping layer 44b is made of silicon nitride (SiN)_x) Made and having a thickness of 0.1 μm. Thus, the blue light transmittance of the wavelength converting underlayer 74 is 81.3%.

In fig. 11, the low-refractive base layer 25 of the wavelength converting base layer 75 is a single-layer structure, and the low-refractive cover layers 45a and 45b are multi-layer structures in which materials having different refractive indices are alternately laminated. The wavelength conversion underlayer 75 of fig. 11 is a structure corresponding to result 1 of case 3 in fig. 6C. That is, in the wavelength converting substrate 75 of fig. 11, the low-refractive substrate 25 may have a single-layer structure including a high-refractive material, and the low-refractive cover layers 45a and 45b may be a multi-layer including the first and second low-refractive cover layers 45a and 45b having different refractive indices. The refractive index of the first low-refractive cover layer 45a may be smaller than that of the second low-refractive cover layer 45 b. The low-refractive index underlayer 25 may be made of the same material as the second low-refractive index covering layer 45 b. In an exemplary embodiment, the low refractive underlayer 25 is made of silicon nitride (SiN)_x) Made and having a thickness of 0.02 μm. The first low-refractive index coating layer 45a is made of silicon oxide (SiO)_x) Made and having a thickness of 0.06 μm. The second low-refractive cover layer 45b is made of silicon nitride (SiN)_x) Made and having a thickness of 0.04 μm. Thus, the blue light transmittance of the wavelength conversion underlayer 75 is 81.4%.

in FIG. 12, the low refractive index underlayer 26 of the wavelength converting underlayer 76 hasThere is a single-layer structure, and the low-refractive cover layers 46a and 46b have a multi-layer structure in which materials having different refractive indices are alternately laminated. The wavelength conversion underlayer 76 of fig. 12 is a structure corresponding to results 1 and 2 of case 4 in fig. 6D. That is, in the wavelength converting underlayer 76 of fig. 12, the low-refractive underlayer 26 may have a single-layer structure including a high-refractive material, and the low-refractive cladding layers 46a and 46b may be multiple layers including the first and second low-refractive cladding layers 46a and 46b having different refractive indices. The refractive index of the first low-refractive index covering layer 46a may be smaller than that of the second low-refractive index covering layer 46 b. The wavelength converting underlayer 76 in fig. 12 may include the same number of layers as in fig. 11. However, in the exemplary embodiment of fig. 12, the low-refractive underlayer 26 may be made of a low-refractive material. In addition, the low-refractive underlayer 26 may be made of the same material as the first low-refractive cover layer 46 a. In an exemplary embodiment, the low refractive index underlayer 26 is made of silicon oxide (SiO)_x) Made and having a thickness of 0.06 μm. The first low-refractive index coating layer 46a is made of silicon oxide (SiO)_x) Made and having a thickness of 0.08 μm. The second low-refractive cap layer 46b is made of silicon nitride (SiN)_x) Made and having a thickness of 0.02 μm. Thus, the blue light transmittance of the wavelength conversion underlayer 76 is 81.4%. The wavelength converting underlayer 76 according to the exemplary embodiment is the same as the wavelength converting underlayer 76 of the above-described exemplary embodiment in terms of the laminate material, but the thickness of each layer is different. The thickness of the low refractive index underlayer 26 is 0.04 μm. The thickness of the first low-refractive index coating layer 46a is 0.08 μm. The thickness of the second low-refractive index covering layer 46b was 0.02 μm. Thus, the blue light transmittance of the wavelength conversion underlayer 76 is 81.3%.

In fig. 13, the low refractive base layers 27a and 27b and the low refractive cover layers 47a and 47b of the wavelength converting base layer 77 have a multi-layered structure in which materials having different refractive indices are alternately laminated. The wavelength conversion underlayer 77 of fig. 13 is a structure corresponding to results 2 and 3 of case 3 in fig. 6C. That is, in the wavelength conversion substrate 77 of fig. 13, the low refractive substrates 27a and 27b may be a multilayer including the first and second low refractive substrates 27a and 27b having different refractive indexes, and the low refractive cover layer47a and 47b may be a multilayer including a first low-refractive index covering layer 47a and a second low-refractive index covering layer 47b having different refractive indices. The refractive index of the first low-refractive underlayer 27a may be greater than that of the second low-refractive underlayer 27 b. The refractive index of the first low-refractive index cover layer 47a may be smaller than that of the second low-refractive index cover layer 47 b. In addition, the first low-refractive base layer 27a may be made of the same material as the second low-refractive cover layer 47b, and the second low-refractive base layer 27b may be made of the same material as the first low-refractive cover layer 47 a. In an exemplary embodiment, the first low refractive underlayer 27a is made of silicon nitride (SiN)_x) Made and having a thickness of 0.02 μm. The second low-refractive bottom layer 27b is made of silicon oxide (SiO)_x) Made and having a thickness of 0.02 μm. The first low-refractive index coating layer 47a is made of silicon oxide (SiO)_x) Made and having a thickness of 0.04 μm. The second low-refractive cap layer 47b is made of silicon nitride (SiN)_x) Made and having a thickness of 0.06 μm. Thus, the blue light transmittance of the wavelength conversion underlayer 77 is 81.4%. The wavelength converting base layer 77 according to the embodiment is the same as the wavelength converting base layer 77 of the above-described exemplary embodiment in terms of the laminate, but the thickness of each layer is different. The thickness of the first low-refractive index underlayer 27a is 0.02 μm. The thickness of the second low-refractive index covering layer 47b was 0.04 μm. The thickness of the first low-refractive index covering layer 47a is 0.02 μm. The thickness of the second low-refractive index coating layer 47b was 0.08 μm. Thus, the blue light transmittance of the wavelength conversion underlayer 77 is 81.4%.

In fig. 14, in contrast to fig. 10, the wavelength converting underlayer 78 does not include a low-refractive covering layer, and the low-refractive underlayers 28a and 28b have a multilayer structure. The wavelength conversion underlayer 78 of fig. 14 is a structure corresponding to result 3 of case 1 in fig. 6A. That is, in the wavelength-converting underlayer 78 of fig. 14, the low-refractive covering layer is not provided, that is, the low-refractive covering layer has a thickness of 0 μm, and the low-refractive underlayers 28a and 28b may be a multilayer including the first low-refractive underlayers 28a and the second low-refractive underlayers 28b having different refractive indexes. The refractive index of the first low-refractive underlayer 28a may be greater than the refractive index of the second low-refractive underlayer 28 b. In an exemplary embodiment, the first low refractive underlayer 28a is made of silicon nitride (SiN)_x) Made and having a thickness of 0.1 μm. The second low-refractive bottom layer 28b is made of silicon oxide (SiO)_x) Made and having a thickness of 0.06 μm. Thus, the blue light transmittance of the wavelength converting underlayer 78 is 81.3%.

FIG. 15A is a table showing the lamination of the wavelength converting cladding layer, and FIG. 15B is a table showing the transmittance with respect to silicon nitride (SiN) on the wavelength converting layer_x) A graph of the change in thickness of (a).

referring to fig. 2 and 15A, the table shows conditions for performing the simulation. A wavelength converting cladding layer 60 may be disposed on the wavelength converting layer 50. The wavelength-converting cladding layer 60 may include a high refractive material, a low refractive material, and a transparent organic material. In an exemplary embodiment, the high refractive material may be silicon nitride (SiN)_x) And the low refractive material may be silicon oxide (SiO)_x). The high refractive material will be described hereinafter as silicon nitride (SiN)_x) And the low refractive material will be described as silicon oxide (SiO) hereinafter_x). OC in fig. 15A refers to a transparent organic material. The transparent organic material may be a silicone resin, an acrylic resin, or an epoxy resin. Each layer including the high refractive material or the low refractive material may have a thickness of 0 to 0.2 μm. The layer including the transparent organic material may have a thickness of 0 μm to 5 μm. A thickness of 0 μm means that the corresponding layer is not included. There may be a total of six conditions according to a laminated structure of layers including a high refractive material, a low refractive material, and a transparent organic material. Hereinafter, three conditions that exhibit a considerably high light transmittance will be described below.

The wavelength-converting overlay layer 60 of case 1 may have a structure in which layers including a high refractive material, a low refractive material, and a transparent organic material are sequentially laminated in this order on the wavelength-converting layer 50.

The wavelength-converting cladding layer 60 of case 2 may have a structure in which layers including a high refractive material, a transparent organic material, and a low refractive material are sequentially laminated in this order on the wavelength-converting layer 50.

the wavelength-converting cladding layer 60 of case 3 may include a structure in which layers including a transparent organic material, a high refractive material, and a low refractive material are sequentially laminated in this order on the wavelength-converting layer 50.

Fig. 15B is a graph showing transmittance with respect to silicon nitride (SiN) provided on the wavelength conversion layer 50 in case 2 of fig. 15A_x) A graph of the change in thickness of (a). Fig. 15B is an example of the simulation result, and the transmittance of the wavelength converting cladding layer 60 having a laminated structure of other cases can also be obtained in the same manner as in fig. 15B. Here, the transmittance indicates a ratio of white light transmitted through the lower wavelength-converting cladding layer 60 to white light incident through the wavelength-converting layer 50. In the graph of FIG. 15B, silicon nitride (SiN)_x) Refers to a high refractive material, and silicon oxide (SiO)_x) Refers to a low refractive material.

referring to fig. 15B, it can be seen that the transmittance of the wavelength converting cladding layer 60 varies with the silicon nitride (SiN) of the wavelength converting cladding layer 60_x) May vary depending on the thickness of the substrate. The influence of constructive or destructive interference due to light is based on silicon nitride (SiN)_x) And thus the light transmittance also changes. With silicon nitride (SiN)_x) The value of the maximum light transmittance tends to decrease due to the absorption of light by the material. When silicon nitride (SiN)_x) The wavelength-converting cladding layer 60 according to case 2 has the maximum transmittance at a thickness of about 0.1 μm. In this way, by changing the laminated structure (e.g., the lamination order and the lamination thickness of the wavelength converting cladding layer 60) according to cases 1 to 3 shown in fig. 15A, the maximum transmittance under each lamination condition can be obtained.

Fig. 16A to 16C are tables showing a laminated structure and a thickness for ensuring the maximum transmittance in each laminated case of the wavelength converting coverlay layer. In fig. 16A to 16C, three resulting values with high transmittance are shown for each lamination case. In fig. 16A to 16C, silicon nitride (SiN)_x) Is an example of a high refractive material, and silicon oxide (SiO)_x) Is an example of a low refractive material. OC refers to a transparent organic material. The wavelength-converting cladding layer 60 may have a maximum light transmission of 87.5% to 88.2% if a maximum light transmission in each case is obtained. Now it isThe laminated structure of the wavelength-converting cladding layer 60 according to various exemplary embodiments will be described in detail with reference to fig. 17 to 20.

Fig. 17 to 20 are sectional views of wavelength converting cladding layers 61 to 64 according to exemplary embodiments. The wavelength converting cladding layers in fig. 17 to 20 show elements in which the wavelength converting cladding layers may be arranged differently. In order to effectively transmit light and prevent moisture/oxygen from penetrating into the wavelength conversion layer 50, the wavelength conversion cladding layers 61 to 64 may each have a multi-layered structure in which layers including at least two of a high refractive material, a low refractive material, and a transparent organic material are laminated.

In fig. 17, wavelength converting cladding layers 61a and 61b are disposed on the wavelength converting layer 50, and have a multilayer structure including a first wavelength converting cladding layer 61a and a second wavelength converting cladding layer 61 b. The wavelength converting cladding layers 61a and 61b of fig. 17 are structures corresponding to results 1 to 3 of case 1 in fig. 16A. That is, the wavelength converting cladding layers 61a and 61b of fig. 17 may not include a high refractive material, and may be a multilayer including the first wavelength converting cladding layer 61a and the second wavelength converting cladding layer 61b having different refractive indices. The refractive index of the first wavelength-converting cladding layer 61a may be greater than the refractive index of the second wavelength-converting cladding layer 61 b. In an exemplary embodiment, the first wavelength-converting cladding layer 61a is made of silicon oxide (SiO)_x) Made and having a thickness of 0.1 μm. The second wavelength-converting cladding layer 61b is made of a transparent organic material and has a thickness of 2 μm. Therefore, the white light transmittance of the wavelength conversion covers 61a and 61b is 87.9%. The wavelength converting overlays 61a and 61b according to the exemplary embodiment are the same as the wavelength converting overlays 61a and 61b of the above-described exemplary embodiment in terms of laminate, but the thickness of each layer is different. The thickness of the first wavelength-converting cladding layer 61a was 0.1 μm. The thickness of the second wavelength-converting cladding layer 61b was 3.5 μm. Accordingly, the white light transmittance of the wavelength conversion covers 61a and 61b is 87.7%. The wavelength converting overlays 61a and 61b according to the exemplary embodiment are the same as the wavelength converting overlays 61a and 61b of the above-described exemplary embodiment in terms of laminate, but the thickness of each layer is different. First wavelength conversion overlayThe thickness of the layer 61a is 0.1 μm. The thickness of the second wavelength-converting cladding layer 61b was 4.5 μm. Accordingly, the white light transmittance of the wavelength conversion covers 61a and 61b is 87.5%.

In fig. 18, wavelength conversion cladding layers 62a and 62b are disposed on the wavelength conversion layer 50, and have a multilayer structure including a first wavelength conversion cladding layer 62a and a second wavelength conversion cladding layer 62 b. The wavelength converting cladding layers 62a and 62B of fig. 18 are structures corresponding to results 1 to 3 of case 2 in fig. 16B. That is, the wavelength converting cladding layers 62a and 62b of fig. 18 may not include a transparent organic material, and may be a multilayer including a first wavelength converting cladding layer 62a and a second wavelength converting cladding layer 62b having different refractive indices. The refractive index of the first wavelength-converting cladding layer 62a may be greater than the refractive index of the second wavelength-converting cladding layer 62 b. In an exemplary embodiment, the first wavelength-converting cladding layer 62a is made of silicon nitride (SiN)_x) Made and having a thickness of 0.1 μm. The second wavelength-converting cladding layer 62b is made of silicon oxide (SiO)_x) Made and having a thickness of 0.05 μm. Accordingly, the white light transmittance of the wavelength conversion covers 62a and 62b is 88.2%. The wavelength converting cladding layers 62a and 62b according to the exemplary embodiment are the same as the wavelength converting cladding layers 62a and 62b of the above-described exemplary embodiment in terms of the laminate, but the thickness of each layer is different. The thickness of the first wavelength-converting cladding layer 62a was 0.1 μm. The thickness of the second wavelength-converting cladding layer 62b was 0.2 μm. Accordingly, the white light transmittance of the wavelength conversion covers 62a and 62b is 87.9%. The wavelength converting cladding layers 62a and 62b according to the exemplary embodiment are the same as the wavelength converting cladding layers 62a and 62b of the above-described exemplary embodiment in terms of the laminate, but the thickness of each layer is different. The thickness of the first wavelength-converting cladding layer 62a was 0.1 μm. The thickness of the second wavelength-converting cladding layer 62b was 0.35 μm. Accordingly, the white light transmittance of the wavelength conversion covers 62a and 62b is 87.7%.

In fig. 19, wavelength conversion covers 63a and 63b are disposed on the wavelength conversion layer 50, and have a multilayer structure including a first wavelength conversion cover 63a and a second wavelength conversion cover 63 b. The wavelength converting cladding layers 63a and 63b of FIG. 19 correspond to those of FIG. 16Structure of result 1 of case 3 in C. That is, the wavelength converting cladding layers 63a and 63b of fig. 19 may not include a low refractive material, and may be a multilayer including a first wavelength converting cladding layer 63a and a second wavelength converting cladding layer 63b having different refractive indices. The refractive index of the first wavelength-converting cladding layer 63a may be smaller than that of the second wavelength-converting cladding layer 63 b. In an exemplary embodiment, the first wavelength-converting cladding layer 63a is made of a transparent organic material and has a thickness of 1 μm. The second wavelength-converting cladding layer 63b is made of silicon nitride (SiN)_x) Made and having a thickness of 0.05 μm. Accordingly, the white light transmittance of the wavelength-converting covers 63a and 63b is 88.2%.

In fig. 20, wavelength-converting cladding layers 64a, 64b, and 64c are provided on the wavelength-converting layer 50, and have a multilayer structure including a first wavelength-converting cladding layer 64a, a second wavelength-converting cladding layer 64b, and a third wavelength-converting cladding layer 64 c. The wavelength converting cladding layers 64a, 64b and 64C of fig. 20 are structures corresponding to results 2 and 3 of case 3 in fig. 16C. That is, the wavelength-converting cladding layers 64a, 64b, and 64c of fig. 20 may be a multilayer including a first wavelength-converting cladding layer 64a, a second wavelength-converting cladding layer 64b, and a third wavelength-converting cladding layer 64c having different refractive indices. The refractive index of the first wavelength-converting cladding layer 64a may be the smallest and the refractive index of the second wavelength-converting cladding layer 64b may be the largest. The refractive index of the third wavelength-converting cladding layer 64c may be greater than that of the first wavelength-converting cladding layer 64a and less than that of the second wavelength-converting cladding layer 64 b. In an exemplary embodiment, the first wavelength-converting cladding layer 64a is made of a transparent organic material and has a thickness of 1 μm. The second wavelength-converting cladding layer 64b is made of silicon nitride (SiN)_x) Made and having a thickness of 0.05 μm. The third wavelength-converting coating layer 64c is made of silicon oxide (SiO)_x) Made and having a thickness of 0.05 μm. Thus, the white light transmittance of the wavelength-converting cladding layers 64a, 64b and 64c is 88.2%. The wavelength converting cladding layers 64a, 64b, and 64c according to the exemplary embodiment are identical in terms of laminate to the wavelength converting cladding layers 64a, 64b, and 64c of the above-described exemplary embodiment, but each layer has a thickness that is not as thickThe same is true. The thickness of the first wavelength-converting cladding layer 64a is 1 μm. The thickness of the second wavelength-converting cladding layer 64b was 0.05 μm. The thickness of the third wavelength-converting cladding layer 64c is 0.3 μm. Thus, the white light transmittance of the wavelength-converting cladding layers 64a, 64b and 64c is 88.2%.

Fig. 21 to 23 are sectional views of the optical members 101 to 103 according to exemplary embodiments. The optical member 101 of fig. 21 to 23 shows the above-described wavelength converting underlayer 70 and wavelength converting overlayer 60 that may be variously combined. The structures of the eight wavelength converting underlayers 71 to 78 described above with reference to fig. 7 to 14 and the structures of the four wavelength converting cladding layers 61 to 64 described above with reference to fig. 17 and 20 may be combined according to an exemplary embodiment to produce 32 optical members (101,102, 103). However, the laminated structure of the optical member is not limited to the above example, and various other laminated structures may be applied. In the optical member according to the exemplary embodiment, the wavelength conversion substrates 71 to 78 described above with reference to fig. 7 to 14 may be divided into the wavelength conversion substrate 74 not including the low refractive substrate 20, the wavelength conversion substrate 78 not including the low refractive cover layer 40, and the wavelength conversion substrates 71, 72, 73, 75, 76, and 77 including both the low refractive substrate and the low refractive cover layer. The wavelength converting cladding layer 60 may be any one of the four wavelength converting cladding layers 61 to 64 described above with reference to fig. 17 and 20.

The final light transmittance of the optical member 100 may be obtained by multiplying the blue light transmittance of the wavelength conversion underlayer 70 by the white light transmittance of the wavelength conversion coating 60.

referring to fig. 21, the optical member 101 according to an exemplary embodiment may include a wavelength conversion underlayer 70 and a wavelength conversion overlayer 60 a. The wavelength-converting substrate 70 may include the low-refractive layer 30 and the low-refractive cover layer 40a, but may not include the low-refractive substrate. The wavelength converting underlayer 70 may be the wavelength converting underlayer 74 depicted in fig. 10. That is, the wavelength converting underlayer 70 may be a wavelength converting underlayer that does not include a low refractive underlayer and includes the low refractive cover layer 40a having a multi-layer structure. The wavelength-converting cladding layer 60a may have a multi-layer structure in which layers including inorganic or organic materials are laminated.

Referring to fig. 22, the optical member 102 according to an exemplary embodiment may include a wavelength conversion underlayer 70 and a wavelength conversion overlayer 60 b. The wavelength-converting substrate 70 may include the low-refractive substrate 20b and the low-refractive layer 30, but may not include the low-refractive cover layer. The wavelength converting underlayer 70 may be the wavelength converting underlayer 78 depicted in fig. 14. That is, the wavelength-converting underlayer 70 may be a wavelength-converting underlayer that does not include a low-refractive cover layer and includes the low-refractive underlayer 20b having a multi-layer structure. The wavelength-converting cladding layer 60b may have a multi-layer structure in which layers including inorganic materials or organic materials are laminated.

Referring to fig. 23, the optical member 103 according to an exemplary embodiment may include a wavelength conversion underlayer 70 and a wavelength conversion overlayer 60 c. The wavelength-converting substrate 70 may include a low-refractive substrate 20c, a low-refractive layer 30, and a low-refractive cover layer 40 c. The wavelength conversion underlayer 70 may be any one of the wavelength conversion underlayers 71, 72, 73, 75, 76, and 77 according to the exemplary embodiment except for the wavelength conversion underlayers 74 and 78 of fig. 10 and 14 among the wavelength conversion underlayers 71 to 78 described above with reference to fig. 7 to 14. That is, the wavelength-converting substrate 70 may include a low refractive substrate 20c having a single-layer structure or a multi-layer structure, and a low refractive cover layer 40c having a single-layer structure or a multi-layer structure. The wavelength-converting cladding layer 60c may be a multilayer structure in which layers including inorganic materials or organic materials are laminated.

Fig. 24 is a cross-sectional view of a display 1000 according to an example embodiment.

Referring to fig. 24, the display 1000 includes a light source 400, an optical member 100 disposed on a light emitting path of the light source 400, and a display panel 300 disposed over the optical member 100.

All of the optical members according to the above-described exemplary embodiments may be used as the optical member 100. In fig. 24, the display 1000 will be described as including the optical member 100 of fig. 2 as an example.

The light source 400 is disposed on a side surface of the optical member 100. The light source 400 may be disposed adjacent to the light incident surface 10S1 of the light guide plate 10 of the optical member 100. The light source 400 may include a plurality of point light sources or line light sources. The point light source may be an LED light source 410. The LED light sources 410 may be mounted on a printed circuit board 420. The LED light source 410 may emit light of a blue wavelength.

As shown in fig. 24, the LED light source 410 may be a top-emitting LED that emits light through its top surface. In this case, the printed circuit board 420 may be disposed on the sidewall 520 of the case 500.

Light of blue wavelength emitted from the LED light source 410 is incident on the light guide plate 10 of the optical member 100. The light guide plate 10 of the optical member 100 guides light and outputs the light through the upper surface 10a or the lower surface 10 b. The wavelength conversion layer 50 of the optical member 100 converts a part of light of a blue wavelength incident from the light guide plate 10 into light of other wavelengths, for example, green and red wavelengths. The green wavelength light and the red wavelength light are emitted upward toward the display panel 300 together with the unconverted blue wavelength light.

The scattering pattern 80 may be disposed on the lower surface 10b of the light guide plate 10. The scattering pattern 80 changes the angle of light propagating in the light guide plate 10 by total reflection, and outputs the light having the changed angle to the outside of the light guide plate 10.

In an exemplary embodiment, the scattering pattern 80 may be provided as a separate layer or a separate pattern. For example, a pattern layer including a protrusion pattern and/or a groove pattern may be formed on the lower surface 10b of the light guide plate 10, or a printed pattern may be formed on the lower surface 10b of the light guide plate 10 to serve as the scattering pattern 80.

In an exemplary embodiment, the scattering pattern 80 may be formed by a surface shape of the light guide plate 10 itself. For example, a groove may be formed on the lower surface 10b of the light guide plate 10 to serve as the scattering pattern 80.

The arrangement density of the scattering patterns 80 may be different according to regions. For example, in a region adjacent to the light incident surface 10S1 provided with a relatively large amount of light, the arrangement density of the scattering patterns 80 may be low, and in a region adjacent to the opposite surface 10S3 provided with a relatively small amount of light, the arrangement density of the scattering patterns 80 may be high.

The display 1000 may further include a reflective member 90 disposed under the optical member 100. The reflective member 90 may include a reflective film or a reflective coating. The reflection member 90 reflects the light output from the lower surface 10b of the light guide plate 10 of the optical member 100 back into the light guide plate 10.

the display panel 300 is disposed over the optical member 100. The display panel 300 receives light from the optical member 100 and displays a screen. Examples of such a light-receiving display panel that receives light and displays a screen include a liquid crystal display panel and an electrophoretic panel. Hereinafter, the display panel 300 will be described as including a liquid crystal display panel, but the inventive concept is not limited thereto and various other light receiving display panels may be applied as the display panel 300.

The display panel 300 may include a first substrate 310, a second substrate 320 facing the first substrate 310, and a liquid crystal layer disposed between the first substrate 310 and the second substrate 320. The first substrate 310 and the second substrate 320 overlap each other. In an exemplary embodiment, any one of the first and second substrates 310 and 320 may be larger than the other substrate and protrude more outward than the other substrate. Fig. 24 shows that the second substrate 320 disposed on the first substrate 310 is large and protrudes on the side where the light source 400 is disposed. The protruding region of the second substrate 320 may provide a space for mounting a driving chip or an external circuit board. Unlike the above example, the first substrate 310 disposed under the second substrate 320 may have a size larger than that of the second substrate 320 and may protrude outward. The overlapping area of the first substrate 310 and the second substrate 320 except for the protruding area in the display panel 300 may be substantially aligned with the side surface 10S of the light guide plate 10 of the optical member 100.

The optical member 100 may be coupled to the display panel 300 by the inter-module coupling member 610. The inter-module coupling member 610 may be shaped like a quadrangular frame in a plan view. The inter-module coupling member 610 may be located at edge portions of the display panel 300 and the optical member 100.

In an exemplary embodiment, a lower surface of the inter-module coupling member 610 is disposed on an upper surface of the wavelength converting cladding layer 60 of the optical member 100. A lower surface of the inter-module coupling member 610 may be disposed on the wavelength conversion cover layer 60 to overlap only the upper surface of the wavelength conversion layer 50 and not the side surface of the wavelength conversion layer 50.

inter-module coupling member 610 may include a polymer resin or an adhesive or tape.

In an exemplary embodiment, the inter-module coupling member 610 may also perform a light transmission blocking function. For example, inter-module coupling member 610 may include a light absorbing material (e.g., a black pigment or dye) or may include a reflective material to perform a light transmission blocking function.

The display 1000 may also include a housing 500. The case 500 has an open surface, and includes a bottom surface 510 and a sidewall 520 connected to the bottom surface 510. The light source 400, the optical member 100 and the display panel 300 attached to each other, and the reflection member 90 may be accommodated in a space defined by the bottom surface 510 and the sidewall 520. The light source 400, the reflective member 90, and the optical member 100 and the display panel 300 attached to each other are disposed on the bottom surface 510 of the case 500. The height of the sidewall 520 of the case 500 may be substantially the same as the height of the optical member 100 and the display panel 300 attached to each other inside the case 500. The display panel 300 may be disposed adjacent to an upper end of each sidewall 520 of the case 500, and may be coupled to the upper end of each sidewall 520 of the case 500 by a case coupling member 620. The housing coupling member 620 may be shaped like a quadrangular frame in a plan view. The housing coupling member 620 may include a polymer resin or an adhesive or tape.

The display 1000 may also include at least one optical film 200. One or more optical films 200 may be received in a space surrounded by the inter-module coupling member 610 between the optical member 100 and the display panel 300. Side surfaces of one or more optical films 200 may be in contact with an inner side surface of the inter-module coupling member 610 and attached to the inner side surface of the inter-module coupling member 610. Although fig. 24 shows that there is a gap between the optical film 200 and the optical member 100, and there is a gap between the optical film 200 and the display panel 300, the gap is not essential and may be omitted.

The optical film 200 may be a prism film, a diffuser film, a microlens film, a lenticular film, a polarizing film, a reflective polarizing film, or a retardation film. Display 1000 may include multiple optical films 200 of the same type or different types. When a plurality of optical films 200 are applied, the optical films 200 may be placed to overlap each other, and side surfaces of the optical films 200 may be in contact with and attached to inner side surfaces of the inter-module coupling member 610. The optical films 200 may be separated from each other, and an air layer may be disposed between the optical films 200.

in the display 1000 according to the exemplary embodiment of fig. 24, the optical member 100 and the display panel 300 and further the optical film 200 are integrated with each other by the inter-module coupling member 610, and the display panel 300 and the housing 500 are coupled with each other by the housing coupling member 620. Accordingly, various members can be stably coupled even if the mold frame is omitted, thereby reducing the weight of the display 1000. In addition, since the light guide plate 10 and the wavelength conversion layer 50 are integrated with each other, the thickness of the display 1000 may be reduced. In addition, since the side surface of the display panel 300 is coupled to the sidewall 520 of the case 500 through the case coupling member 620, a bezel space at the side of the display screen may be eliminated or minimized.

Fig. 25 is a cross-sectional view of a display 1001 according to an example embodiment.

Referring to fig. 25, the display 1001 includes a light source 400, an optical member 100_1 disposed on an emission path of the light source 400, and a display panel 300 disposed over the optical member 100_ 1. Unlike the display 1000 of fig. 24, the display 1001 illustrated in fig. 25 includes the optical member 100_1 in which the wavelength conversion cover layer 60_1 covers the upper surface and the side surface of the wavelength conversion layer 50_1 and the side surface of the wavelength conversion underlayer 70_ 1.

The wavelength conversion layer 50_1 (particularly, the wavelength conversion particles included in the wavelength conversion layer 50_ 1) is susceptible to moisture/oxygen. In the case of the wavelength conversion film, barrier films are laminated on the upper and lower surfaces of the wavelength conversion layer to prevent moisture/oxygen from penetrating into the wavelength conversion layer. However, in the illustrated exemplary embodiment, since the wavelength conversion layer 50_1 is directly disposed without the blocking film, a sealing structure for protecting the wavelength conversion layer 50_1 is required. The sealing structure may be implemented by the wavelength conversion coating layer 60_1 and the light guide plate 10_ 1.

The inlet and outlet through which moisture can permeate into the wavelength conversion layer 50_1 are the upper surface, side surface, and lower surface of the wavelength conversion layer 50_ 1. As described above, since the upper surface and the side surfaces of the wavelength conversion layer 50_1 are covered and protected by the wavelength conversion cover layer 60_1, the penetration of moisture/oxygen can be prevented or at least reduced.

On the other hand, the lower surface of the wavelength conversion layer 50_1 is in contact with the upper surface of the wavelength conversion underlayer 70_ 1. If the wavelength conversion underlayer 70_1 includes the voids VD or is made of an organic material, movement of moisture in the wavelength conversion underlayer 70_1 is possible. Accordingly, moisture/oxygen may be introduced into the lower surface of the wavelength conversion layer 50_1 through the wavelength conversion underlayer 70_ 1. However, since the wavelength conversion underlayer 70_1 according to the exemplary embodiment also has a sealing structure, it is possible to block moisture/oxygen from penetrating through the lower surface of the wavelength conversion layer 50_1 at the source.

Specifically, since the side surface of the wavelength conversion underlayer 70_1 is covered and protected by the wavelength conversion cover layer 60_1, moisture/oxygen permeation through the side surface of the wavelength conversion underlayer 70_1 can be blocked/reduced. Even if the wavelength conversion underlayer 70_1 protrudes more than the wavelength conversion layer 50_1 so that a part of the upper surface is exposed, since the exposed part is covered and protected by the wavelength conversion cover layer 60_1, moisture/oxygen permeation through the exposed part can be blocked/reduced. The lower surface of the wavelength conversion substrate 70_1 is in contact with the light guide plate 10_ 1. When the light guide plate 10_1 is made of an inorganic material such as glass, it may block/reduce penetration of moisture/oxygen like the wavelength conversion coating layer 60_ 1. That is, since the laminated surfaces of the wavelength conversion substrate 70_1 and the wavelength conversion layer 50_1 are surrounded and sealed by the wavelength conversion cover layer 60_1 and the light guide plate 10_1, even if a moisture/oxygen movement path is formed inside the wavelength conversion substrate 70_1, the penetration of moisture/oxygen can be blocked/reduced by the above-described sealing structure. Thus, degradation of the wavelength converting particles due to moisture/oxygen may be prevented or at least mitigated.

the optical member according to the exemplary embodiment may simultaneously perform a light guiding function and a wavelength conversion function while improving light transmission efficiency by a material having a laminated structure of different refractive indexes. The optical member according to the exemplary embodiment is relatively thin and may improve optical characteristics of the display by maximizing light transmission efficiency.

while certain exemplary embodiments and implementations have been described herein, other implementations and modifications will be apparent from this description. The inventive concept is therefore not limited to the embodiments but is to be accorded the widest scope consistent with the claims appended hereto and with various obvious modifications and equivalent arrangements which will be apparent to those skilled in the art.