阅读说明：本技术 小光束角的光源 (Light source with small beam angle ) 是由 唐文婷 张瑞 陈宝瑨 蔡勇 于 2019-02-26 设计创作，主要内容包括：本发明公开了一种小光束角的光源,包括半导体发光元件和透镜,所述半导体发光元件被包埋于透镜内并与透镜无缝结合,所述透镜具有顶面以及与顶面连接的侧面,所述半导体发光元件具有一个以上出光面,其中至少一个出光面朝向所述透镜的顶面设置,并且由所述半导体发光元件射向所述透镜侧面的至少部分光线能够被所述透镜侧面反射后沿光轴透射出。本发明的小光束角的光源结构简单,将反射式照明应用中的光利用效率大大增加；相比于未加透镜的光源,使出光功率提高10％以上；与二次透镜相比,所述一次透镜体积小、重量轻,在光源封装时实现与芯片的无缝连接,便于安装,出光率提高；同时制程简单便捷、低成本、体积小、适于规模化制造和应用。(The invention discloses a light source with a small beam angle, which comprises a semiconductor light-emitting element and a lens, wherein the semiconductor light-emitting element is embedded in the lens and is seamlessly combined with the lens, the lens is provided with a top surface and a side surface connected with the top surface, the semiconductor light-emitting element is provided with more than one light-emitting surface, at least one light-emitting surface is arranged towards the top surface of the lens, and at least part of light emitted to the side surface of the lens by the semiconductor light-emitting element can be reflected by the side surface of the lens and then transmitted out along an optical axis. The light source with a small beam angle has a simple structure, and greatly increases the light utilization efficiency in reflective lighting application; compared with a light source without a lens, the light emitting power is improved by more than 10%; compared with a secondary lens, the primary lens has small volume and light weight, realizes seamless connection with a chip when a light source is packaged, is convenient to mount and improves the light-emitting rate; meanwhile, the manufacturing process is simple, convenient and fast, low in cost and small in size, and is suitable for large-scale manufacturing and application.)

1. A light source with a small beam angle is characterized by comprising a semiconductor light-emitting element and a lens, wherein the semiconductor light-emitting element is embedded in the lens and is seamlessly combined with the lens, the lens is provided with a top surface and a side surface connected with the top surface, the semiconductor light-emitting element is provided with more than one light-emitting surface, at least one light-emitting surface is arranged towards the top surface of the lens, and at least part of light rays emitted to the side surface of the lens by the semiconductor light-emitting element can be reflected by the side surface of the lens and then transmitted along an optical axis.

2. The small beam angle light source of claim 1, wherein: light directed by the semiconductor light emitting element toward the top surface of the lens can be transmitted out of the top surface of the lens and transmitted along the optical axis.

3. The small beam angle light source of claim 1 or 2, wherein: the ratio of the size of a light-emitting surface of the semiconductor light-emitting element facing the top surface of the lens to the maximum size of the top surface of the lens is less than 2: 3; preferably, the shape of the light-emitting surface of the semiconductor light-emitting element facing the top surface of the lens or the top surface of the lens includes a circle, a rectangle, a diamond or a polygon.

4. The small beam angle light source of claim 1 or 2, wherein: the lens top surface comprises a flat surface or a convex surface.

5. The small beam angle light source of claim 4, wherein: the convex surface comprises any one or combination of a spherical surface, a hyperboloid, a paraboloid and a conical surface; preferably, the convex surface comprises an array of convex surfaces.

6. The small beam angle light source of claim 1, wherein: the side surface of the lens is a transparent surface, and light rays emitted to the side surface of the lens by the semiconductor light-emitting element and having an incidence angle larger than a total reflection angle can be reflected by the side surface of the lens and then transmitted along an optical axis; or, the side surface of the lens is a reflecting surface, and the light emitted to the side surface of the lens by the semiconductor light-emitting element can be reflected by the side surface of the lens and then transmitted along the optical axis.

7. The small beam angle light source of claim 1, wherein: the side surface of the lens is an arc surface.

8. The small beam angle light source of claim 7, wherein: the size of the upper part of the arc-shaped surface is larger than that of the lower part; and/or, the arcuate surface comprises a paraboloid, a sphere, or a hyperboloid.

9. The small beam angle light source of claim 1, wherein: the semiconductor light emitting element comprises an LED chip directly combined with a lens; or the semiconductor light-emitting element comprises an LED chip, at least the light-emitting surface of the LED chip is coated with a fluorescent layer, and the fluorescent layer is directly combined with the lens.

10. The small beam angle light source of claim 1, wherein: the bottom surface of the semiconductor light-emitting element is combined with the substrate, the top surface and the side surface of the semiconductor light-emitting element are light-emitting surfaces, and the top surface and the side surface of the semiconductor light-emitting element are respectively arranged towards the top surface and the side surface of the lens.

Technical Field

The present invention relates to semiconductor lighting source designs, and more particularly to a small beam angle light source.

Background

In recent years, LED light sources have been widely used in the field of lighting. Most of the current LED light sources are generally applied without a primary lens or with a hemispherical primary lens, and the light field obtained by such light sources is usually lambertian, as shown in fig. 1, the beam angle of the lambertian light field is large. In some applications, however, a small beam angle of the LED light source is required, for example: transmission searchlight, transmission flashlight, stage lamp etc. In order to further expand the application market of the LED light source, the LED light source needs to be optimally designed.

At present, the proper secondary lens is designed in the lamp to obtain light with small beam angle, but the light emitted from the LED light source can be effectively collimated by the lens only when the part (0 to +/-theta) of the surface of the secondary lens of the lamp is projected, and becomes the main effective light ray of the lamp. While light that is not projected onto the lens surface (+/-90 deg. -theta), is free to escape, with no significant effect on the illumination distance. Fig. 2 is a schematic diagram of a secondary lens in a conventional lamp.

For the lambertian light field, the light utilization efficiency is only 50% when the angle theta is 45 degrees, as shown in fig. 3, according to the formula calculation; when the angle theta is 30 degrees, the light utilization efficiency is reduced to 25 percent; if the light utilization efficiency is to be 75% or more, the θ angle needs to be smaller than 60 °, which means that the diameter of the lens is increased to a large extent, leading to a series of problems such as increase in the manufacturing cost and difficulty of the lens, and increase in the volume and weight of the lamp. The formula can be expressed as:

in the formula, eta: light utilization efficiency; θ: the included angle between the connecting line of the LED light source and the edge of the lens and the normal direction of the LED light source; i (theta) the intensity of the LED light source at the angle theta.

The secondary lens is an optical lens added in front of the light source in order to obtain a required light field in the process of assembling the lamp. The secondary lens and the light source are usually in a gap and a space and are not connected into a whole. Compared with the primary lens, the secondary lens in the lamp cannot increase the light extraction efficiency of the LED, only can change the propagation path of light emitted from the LED to the outside, and is large in size, heavy in weight and high in cost.

Disclosure of Invention

In view of the shortcomings of the prior art, an object of the present invention is to provide a light source with a small beam angle, which has the advantages of improved light extraction efficiency, simple and convenient process, low cost, small size, etc.

In order to achieve the purpose, the invention adopts the following technical scheme:

the embodiment of the invention provides a light source with a small beam angle, which comprises a semiconductor light-emitting element and a lens, wherein the semiconductor light-emitting element is embedded in the lens and is seamlessly combined with the lens, the lens is provided with a top surface and a side surface connected with the top surface, the semiconductor light-emitting element is provided with more than one light-emitting surface, at least one light-emitting surface is arranged towards the top surface of the lens, and at least part of light emitted to the side surface of the lens by the semiconductor light-emitting element can be reflected by the side surface of the lens and then transmitted out along an optical axis.

In some embodiments, light directed by the semiconductor light emitting element toward the top surface of the lens can be transmitted out of the top surface of the lens and along the optical axis.

Further, the ratio of the size of the light emitting surface of the semiconductor light emitting element facing the top surface of the lens to the maximum size of the top surface of the lens is less than 2: 3.

further, the shape of the light-emitting surface of the semiconductor light-emitting element facing the top surface of the lens or the top surface of the lens includes a circle, a rectangle, a diamond or a polygon.

Further, the lens top surface comprises a flat surface or a convex surface.

Furthermore, the side surface of the lens is a transparent surface, and light rays emitted to the side surface of the lens by the semiconductor light-emitting element and having an incidence angle larger than a total reflection angle can be reflected by the side surface of the lens and then transmitted along an optical axis; or, the side surface of the lens is a reflecting surface, and the light emitted to the side surface of the lens by the semiconductor light-emitting element can be reflected by the side surface of the lens and then transmitted along the optical axis.

Compared with the prior art, the invention has at least the following advantages:

1) the light source with the small beam angle has a simple structure, can effectively improve the light extraction efficiency, has simple and convenient manufacturing process, low cost and small volume, and is suitable for large-scale manufacturing and application;

2) the light source with small beam angle provided by the invention greatly increases the utilization efficiency of light in reflective lighting application; compared with a light source without a lens, the light emitting power is improved by more than 10%; compared with a secondary lens, the primary lens has small volume and light weight, realizes seamless connection with a chip when a light source is packaged, is convenient to mount and improves the light-emitting rate;

3) compared with a common Lambertian light field, the light source with a small beam angle provided by the invention has the advantages that the diameter of the lamp lens can be greatly reduced under the condition of the same light utilization efficiency, and the volume weight of the lamp is correspondingly reduced.

Drawings

FIG. 1 is a schematic diagram of a Lambertian light field.

Fig. 2 is a schematic diagram of a secondary lens in a luminaire.

Fig. 3 is a graph of the light utilization efficiency of the lambertian light field versus angle.

Fig. 4 a-4 b are schematic diagrams of a light source with a small beam angle and corresponding light field distribution diagrams, respectively, according to a preferred embodiment of the present invention.

FIG. 5 is a graph of light utilization efficiency versus angle for a light source with a small beam angle in accordance with a preferred embodiment of the present invention.

Fig. 6 a-6 f are schematic structural diagrams of a light source with a small beam angle according to various preferred embodiments of the present invention.

Fig. 7 a-7 b are schematic diagrams of a light source with a small beam angle and corresponding light field distribution diagrams, respectively, according to another preferred embodiment of the present invention.

Description of reference numerals: 1-primary lens, 2-fluorescent layer, 3-LED chip, 4-packaging substrate and 5-reflecting cup.

Detailed Description

In view of the deficiencies in the prior art, the inventors of the present invention have made extensive studies and extensive practices to provide technical solutions of the present invention. The technical solution, its implementation and principles, etc. will be further explained as follows.

An aspect of an embodiment of the present invention provides a light source with a small beam angle, which includes a semiconductor light emitting element and a lens, wherein the semiconductor light emitting element is embedded in the lens and is seamlessly combined with the lens, the lens has a top surface and a side surface connected with the top surface, the semiconductor light emitting element has more than one light emitting surface, at least one light emitting surface is arranged towards the top surface of the lens, and at least part of light rays emitted by the semiconductor light emitting element to the side surface of the lens can be reflected by the side surface of the lens and then transmitted along an optical axis.

In some embodiments, light directed by the semiconductor light emitting element toward the top surface of the lens can be transmitted out of the top surface of the lens and along the optical axis.

In some embodiments, a ratio of a size (e.g., a diameter or a diagonal length) of a light exit surface of the semiconductor light emitting element facing the lens top surface to a maximum size (e.g., a diameter or a diagonal length) of the lens top surface is less than 2: 3.

in some embodiments, the shape of the light exit surface of the semiconductor light emitting element facing the top surface of the lens or the top surface of the lens is a circle or a square, and the square may be a rectangle, a diamond, a polygon, or the like, but is not limited thereto. When the light-emitting surface of the semiconductor light-emitting element facing the top surface of the lens or the top surface of the lens is circular, the size is calculated by the diameter; when the light-emitting surface of the semiconductor light-emitting element facing the top surface of the lens or the top surface of the lens is square, the size is calculated by the length of a diagonal line.

In some embodiments, the top surface of the lens includes, but is not limited to, a flat surface or a convex surface.

Further, the convex surface includes any one or a combination of more of a spherical surface, a hyperboloid, a paraboloid, a conical surface, etc., for example, the convex surface may be an array-type convex surface, etc., but is not limited thereto.

In some embodiments, the side surface of the lens is a transparent surface, and light rays emitted by the semiconductor light-emitting element to the side surface of the lens and having an incident angle larger than a total reflection angle can be reflected by the side surface of the lens and then transmitted along an optical axis; or, the side surface of the lens is a reflecting surface, and the light emitted to the side surface of the lens by the semiconductor light-emitting element can be reflected by the side surface of the lens and then transmitted along the optical axis.

In some embodiments, the lens sides are arcuate.

Further, the size (e.g., diameter or diagonal length) of the upper portion of the arc-shaped face is larger than the size (e.g., diameter or diagonal length) of the lower portion.

Furthermore, the side surface of the lens is an arc surface (a transparent surface or a reflecting surface) with a small lower part and a large upper part, and the top surface of the lens is a convex surface (a transparent surface), so that light emitted from the light field along the axial direction of the light source is converged to form a small beam angle.

Further, the arc surface includes a paraboloid, a sphere, a hyperboloid, etc., and the transmission surface and the reflection surface may be, but not limited to, the above.

Further, the lens is made of a transparent material, and may specifically include, but is not limited to, silicone, PC, PMMA, glass, PP, PS, PVC, PET, ABS, SAN, and the like.

In some embodiments, the semiconductor light emitting element comprises an LED chip directly bonded to a lens; or the semiconductor light-emitting element comprises an LED chip, at least the light-emitting surface of the LED chip is coated with a fluorescent layer, and the fluorescent layer is directly combined with the lens.

Further, the number of the LED chips is more than 1, and the LED chips may be LED chips with various wavelengths such as blue light, red light, green light, yellow light, infrared light, and the like, but is not limited thereto.

Further, the material of the fluorescent layer is fluorescent powder, and the fluorescent powder may be fluorescent powder with different wavelengths such as non-fluorescent powder, yellow fluorescent powder, green fluorescent powder, red fluorescent powder, but is not limited thereto.

Further, the maximum diameter of the top convex surface of the primary lens is more than 1.5 times of the size of the fluorescent layer.

In some embodiments, the bottom surface of the semiconductor light emitting element is bonded to the substrate, the top surface and the side surface of the semiconductor light emitting element are both light emitting surfaces, and the top surface and the side surface of the semiconductor light emitting element are respectively disposed toward the top surface and the side surface of the lens.

Furthermore, seamless connection among the primary lens, the fluorescent layer and the semiconductor light-emitting element is realized. The side arc surface of the primary lens has a function of reflecting out the large-angle light emitted from the semiconductor light emitting element and entering the primary lens through the fluorescent layer. The convex surface at the top of the primary lens has the function of refracting light rays with smaller angles to axially converge towards the light source.

In summary, the light source with a small beam angle of the present invention has a simple structure, and greatly increases the light utilization efficiency in reflective lighting applications; compared with a light source without a lens, the light emitting power is improved by more than 10%; compared with a secondary lens, the primary lens has small volume and light weight, realizes seamless connection with a chip when a light source is packaged, is convenient to mount and improves the light-emitting rate; meanwhile, the manufacturing process is simple, convenient and fast, low in cost and small in size, and is suitable for large-scale manufacturing and application.

In order to make the objects, technical solutions and advantages of the present invention more apparent, the following detailed description of the embodiments of the present invention is provided in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative of the invention, and that experimental conditions and set parameters therein are not to be considered as limitations of the basic embodiments of the invention. And the scope of the present invention is not limited to the following examples. In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

Referring to fig. 6a, a typical structure of an LED light source with a small beam angle according to an exemplary embodiment of the invention includes a primary lens 1, a fluorescent layer 2, an LED chip 3, and a package substrate 4. The primary lens is connected with the LED chip 3 or the fluorescent powder glue in a seamless mode. Specifically, a light-emitting surface of the LED chip 3 is coated with a fluorescent layer 2, and the fluorescent layer 2 is directly combined with the primary lens 1. The bottom surface of the LED chip 3 is combined with the packaging substrate 4, the top surface and the side surface of the LED chip 3 are light emitting surfaces, and the top surface and the side surface of the LED chip 3 are respectively arranged towards the top surface and the side surface of the primary lens 1.

The side surface of the primary lens 1 is an arc surface (a transparent surface or a reflecting surface) with a small lower part and a large upper part, and the top surface of the primary lens 1 is a convex surface (a transparent surface), so that light is emitted from a light field along the axial direction of a light source and converged to form a small beam angle. The primary lens 1 is provided with a top surface and a side surface connected with the top surface, the LED chip 3 is provided with more than one light-emitting surface, wherein at least one light-emitting surface is arranged towards the top surface of the primary lens 1, and at least part of light emitted to the side surface of the primary lens 1 from the LED chip 3 can be reflected by the side surface of the primary lens 1 and then transmitted out along an optical axis.

Wherein, seamless connection is realized among the primary lens 1, the fluorescent layer 2 and the LED chip 3. The side cambered surface of the primary lens 1 has the function of reflecting out the large-angle light which is emitted from the LED chip 3 and enters the primary lens 1 through the fluorescent layer 2 along the axial direction of the light source (the side cambered surface of the primary lens 1 is a transparent surface, the light which is larger than the total reflection angle is reflected out along the axial direction of the light source, and the side cambered surface of the primary lens 1 is a reflecting surface, all the light is reflected out), and the top convex surface of the primary lens 1 has the function of refracting the light with a smaller angle to converge towards the axial direction of the light source.

Further, the ratio of the diameter of the light emitting surface of the LED chip 3 facing the top surface of the primary lens 1 to the maximum diameter of the top surface of the primary lens 1 is less than 2: 3.

further, the diameter of the light emitting surface of the LED chip 3 corresponding to the top surface of the primary lens 1 is smaller than the diameter of the top surface of the primary lens 1, i.e., L1 in fig. 6a is greater than 1.5xL 2.

Further, in the preferred embodiment, the primary lens 1 is made of a transparent material, and may specifically include, but is not limited to, silicone, PC, PMMA, glass, PP, PS, PVC, PET, ABS, SAN, and the like.

Further, the number of the LED chips 3 in the preferred embodiment is 1 or more, and the LED chips may be LED chips of various wavelengths such as blue light, red light, green light, yellow light, infrared light, etc., but is not limited thereto.

Further, in the preferred embodiment, the material of the fluorescent layer 2 is phosphor, and the phosphor may be phosphor with different wavelengths such as non-phosphor, yellow phosphor, green phosphor, red phosphor, but is not limited thereto.

Further, the maximum diameter of the top convex surface of the primary lens 1 is 1.5 times or more the size of the fluorescent layer 2.

The working principle of the LED light source with a small beam angle in this embodiment is at least:

the function of the primary lens side cambered surface is as follows:

reflecting the light with large angle along the axial direction of the light source; (the side cambered surface of the primary lens is a transparent surface which reflects light rays with a larger total reflection angle along the axial direction of the light source, and the side cambered surface of the primary lens is a reflecting surface which reflects all light rays

The function of the top convex surface of the primary lens is as follows:

the light rays with smaller angles are refracted to be converged towards the light source in the axial direction.

Further, the diameter of the top concave surface of the primary lens is larger than the size of the fluorescent layer.

Further, the primary lens realizes seamless connection with the LED chip during packaging, and the optical power is improved.

Through testing, the graph of the light utilization efficiency of the LED light source with a small beam angle of the present embodiment is shown in fig. 5. Wherein, when the angle theta is 30 degrees, the light utilization efficiency is more than 58 percent; when the angle theta is 45 degrees, the light utilization efficiency is more than 90 percent; compared with a common Lambertian light field, under the condition of the same light utilization efficiency, the diameter of the secondary lens of the lamp can be greatly reduced, and the volume and the weight of the lamp are correspondingly reduced.

Further, the convex surface of the primary lens may be any one or a combination of more than one of a spherical surface, a hyperboloid surface, a paraboloid surface and a conical surface, for example, the convex surface may be an array convex surface, etc., the side surface of the lens includes a transparent arc surface with a small lower part and a large upper part, and the arc surface may be a paraboloid, a spherical surface or a hyperboloid surface, etc., therefore, the specific structure of the LED light source with a small beam angle of the present invention has many forms, for example, the structures shown in fig. 6 b-6 f can be referred to, but not limited to, these structures. Fig. 6d also shows a reflector cup 5.

Referring to fig. 4 a-4 b, the actual diagram and the corresponding light field distribution diagram of the LED light source with a small beam angle in a preferred embodiment of the invention show that the optical power efficiency is improved by 15% after the primary lens shown in fig. 4a is added, and as can be seen from fig. 4b, the experimental structure shows that the 50% beam angle is about 60 °.

Further, fig. 7 a-7 b show physical diagrams of LED light sources with small beam angles and corresponding light field distribution diagrams in another preferred embodiment of the present invention.

In summary, according to the above technical solution of the present invention, the light source with a small beam angle of the present invention greatly increases the utilization efficiency of light in reflective lighting applications; compared with a light source without a lens, the light emitting power is improved by more than 10%; compared with a secondary lens, the primary lens is small in size and light in weight, realizes seamless connection with a chip when a light source is packaged, is convenient to install, can effectively improve light extraction efficiency, is simple and convenient in manufacturing process, low in cost and small in size, and is suitable for large-scale manufacturing and application.

It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

It should be understood that the above-mentioned embodiments are merely illustrative of the technical concepts and features of the present invention, which are intended to enable those skilled in the art to understand the contents of the present invention and implement the present invention, and therefore, the protection scope of the present invention is not limited thereby. All equivalent changes and modifications made according to the spirit of the present invention should be covered within the protection scope of the present invention.