阅读说明：本技术 放射角度变换元件及发光装置 (Radiation angle conversion element and light emitting device ) 是由 常友启司 日下哲 于 2020-04-06 设计创作，主要内容包括：接合于壳体的放射角度变换元件(10)包括玻璃基板(12)和设于玻璃基板(12)上的具有微透镜阵列(16)的树脂层(14)。在与壳体的接合部分(18),在玻璃基板(12)上未形成树脂层(14)。(A radiation angle conversion element (10) joined to a case includes a glass substrate (12) and a resin layer (14) having a microlens array (16) provided on the glass substrate (12). The resin layer (14) is not formed on the glass substrate (12) at the joint portion (18) with the housing.)

1. A radiation angle changing element joined to a housing,

the method comprises the following steps: glass substrate, and

a resin layer having an optical functional portion provided on the glass substrate;

the resin layer is not formed on the glass substrate at a joint portion with the case.

2. The radiation angle changing element according to claim 1,

the engaging portion is provided outside the resin layer.

3. The radiation angle changing element according to claim 1 or 2,

in the joint portion, a metal film is formed on the glass substrate.

4. The radiation angle changing element according to claim 3,

the metal film is formed on the outer side of the resin layer at the joint portion, and an exposed portion of the glass substrate is provided on the outer side of the metal film.

5. The radiation angle changing element according to any one of claims 1 to 3,

the optical function portion is a microlens array in which a plurality of microlenses are two-dimensionally arranged.

6. A light emitting device including a case, a light emitting element disposed in the case, and an emission angle conversion element joined to the case and converting an emission angle of light from the light emitting element,

the radiation angle changing element includes:

glass substrate, and

a resin layer having an optical functional portion provided on the glass substrate,

the resin layer is not formed on the glass substrate at a joint portion with the case.

Technical Field

The present invention relates to a radiation angle conversion element for converting a radiation angle of an incident light beam.

Background

A radiation angle conversion element that scatters or converts incident light in various directions is used for a display device of a display, a screen, or the like, and is widely used for various devices such as an illumination device for the purpose of obtaining uniform illumination intensity. In general, the emission angle of light emitted from a light source is often increased.

In recent years, high performance has been further demanded for the angle of light emission, the intensity distribution for each angle, the uniformity of in-plane intensity when diffused light is projected, and the like. For example, there are the following requirements: light emitted from an array-like Surface Emitting Laser (VCSEL) at a predetermined divergence angle is diffused in a wider angular range, and it is desired to have anisotropy in the diffusion angle.

There are several types of elements that diffuse or change the angle of light. For example, an element in which fine spaces are dispersed or fine particles are dispersed in a flat plate (for example, a translucent resin plate), an element in which fine irregularities are randomly formed on the surface of a substrate (for example, glass having a rough surface by etching or the like), an element in which designed irregularities are formed by processing the surface of a substrate (for example, a diffraction-type element), an element in which a plurality of lenses are arranged on the surface of a substrate (for example, a microlens array), and the like are known.

Among these, a radiation angle conversion element using a microlens array has high transmittance and is easy to control the diffusion angle, and therefore is used when high diffusion performance is required (for example, see patent documents 1 and 2).

Prior art documents

Patent document

Patent document 1: japanese laid-open patent publication No. 2009-42772

Patent document 2: japanese patent laid-open publication No. 2017-9669

Disclosure of Invention

Problems to be solved by the invention

Fig. 1 is a schematic cross-sectional view showing an example of a light-emitting device 100 using a conventional emission angle conversion element 101. The light emitting device 100 includes a housing 102, a light emitting element 104, and a radiation angle changing element 101.

The housing 102 is formed of, for example, ceramic and has a box shape with an open upper surface. A light emitting element 104 such as a VCSEL is fixed to the bottom surface 102a of the housing 102. The radiation angle conversion element 101 is an element in which a resin microlens array 108 is formed on a glass substrate 106. The radiation angle conversion element 101 is joined to the case 102 in a capping manner, whereby a space in which the light emitting element 104 is provided is sealed. The radiation angle conversion element 101 is generally provided so that the surface on which the microlens array 108 is formed faces the light emitting element 104.

Fig. 2 is an enlarged view of a joint portion C of the radiation angle changing element 101 and the housing 102 shown in fig. 1. As a method of bonding the radiation angle conversion element 101 to the case 102, there are bonding using an adhesive such as a thermosetting adhesive or a UV-curable adhesive, solder bonding, a bonding method of melting a low melting point glass, diffusion bonding, and the like. In any case, the radiation angle conversion element 101 and the case 102 are joined by the glass substrate 106 and the opposing portion C1 of the side surface of the microlens array 108 and the case 102, and the opposing portion C2 of the microlens array 108 and the case 102.

As described above, in the portion where the resin microlens array 108 and the ceramic case 102 are joined, there is a possibility that the joining strength is weakened due to a problem of adhesion between the materials. In addition, since the thermal expansion coefficients of the ceramic and the resin are different, the above-described junction has a side surface where thermal shock is weak. Further, in the above-described bonding, since the heat resistance of the resin microlens array is not so high, there is a problem that a bonding method requiring high temperature of several hundreds of degrees, such as bonding by soldering or bonding by low melting point glass, cannot be used.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a radiation angle conversion element which can be firmly joined to a housing.

Means for solving the problems

In order to solve the above problem, a radiation angle conversion element according to an aspect of the present invention is a radiation angle conversion element bonded to a case, and includes a glass substrate and a resin layer having an optical function portion provided on the glass substrate. The resin layer is not formed on the glass substrate at the joint portion with the case.

The joint portion may be provided outside the resin layer.

In the bonding portion, a metal film may be formed on the glass substrate.

In the joining portion, a metal film may be formed outside the resin layer, and an exposed portion of the glass substrate may be provided further outside the metal film.

The optical functional portion may be a microlens array in which a plurality of microlenses are two-dimensionally arranged.

Another aspect of the present invention is a light-emitting device. The device includes a case, a light emitting element disposed in the case, and a radiation angle conversion element joined to the case and converting a radiation angle of light from the light emitting element. The radiation angle conversion element includes a glass substrate and a resin layer having an optical function portion provided on the glass substrate. No resin layer is formed on the glass substrate at the joint portion with the case.

Any combination of the above-described constituent elements and a scheme of converting the expression of the present invention between a method, an apparatus, a system, and the like are also effective as a scheme of the present invention.

Effects of the invention

According to the present invention, it is possible to provide a radiation angle changing element that can be firmly joined to a housing.

Drawings

Fig. 1 is a schematic cross-sectional view showing an example of a light-emitting device using a conventional emission angle conversion element.

Fig. 2 is an enlarged view of a joint portion of the radiation angle changing element and the housing shown in fig. 1.

Fig. 3 (a) and (b) are views for explaining the radiation angle conversion element according to embodiment 1 of the present invention.

Fig. 4 is a schematic cross-sectional view showing a light-emitting device using a radiation angle conversion element according to embodiment 1 of the present invention.

Fig. 5 is an enlarged view of a joint portion of the radiation angle changing element and the housing shown in fig. 4.

Fig. 6 (a) and (b) are views for explaining the radiation angle conversion element according to embodiment 2 of the present invention.

Fig. 7 is a schematic cross-sectional view showing a light-emitting device using a radiation angle conversion element according to embodiment 2 of the present invention.

Fig. 8 is an enlarged view of a joint portion of the radiation angle changing element and the housing shown in fig. 7.

Fig. 9 (a) and (b) are views for explaining the radiation angle conversion element according to embodiment 3 of the present invention.

Fig. 10 (a) to (g) are views showing an example of the manufacturing process of the radiation angle conversion element.

Fig. 11 (a) to (g) are views showing another example of the manufacturing process of the radiation angle conversion element.

Fig. 12 (a) to (g) are views showing an example of another manufacturing process of the radiation angle conversion element.

Detailed Description

Hereinafter, embodiments of the present invention will be described. The same or equivalent constituent elements, members, and processes shown in the respective drawings are denoted by the same reference numerals, and overlapping descriptions are appropriately omitted. The embodiments are not intended to limit the invention but to exemplify the invention, and all the features and combinations thereof described in the embodiments are not necessarily essential contents of the invention.

Fig. 3 (a) and (b) are views for explaining the radiation angle conversion element 10 according to embodiment 1 of the present invention. Fig. 3 (a) is a plan view of the radiation angle conversion element 10. Fig. 3 (b) is a sectional view a-a of the radiation angle conversion element 10 shown in fig. 3 (a).

The radiation angle conversion element 10 includes a glass substrate 12. The glass substrate 12 may be made of soda-lime glass, borosilicate glass, or the like, and may have a thickness of 300 μm. The planar size of the glass substrate 12 may be, for example, 2.5mm × 3.0 mm.

The radiation angle changing element 10 further includes a resin layer 14 having an optical function portion. The resin layer 14 is provided on at least one main surface of the glass substrate 12. In embodiment 1, the resin layer 14 has a microlens array 16 in which a plurality of microlenses 15 are two-dimensionally arranged as an optical function portion. The material of the resin layer 14 is not particularly limited as long as it is a resin having a sufficiently high transmittance at a predetermined wavelength to be used, and for example, an epoxy resin, an acrylic resin, a silicone resin, a cycloolefin resin, or a composite material thereof can be used. In embodiment 1, the microlens 15 is a convex lens, but the type of the microlens 15 is not particularly limited, and may be a concave lens, or may be a mixture of a convex lens and a concave lens. The plurality of microlenses 15 may be arranged in a square shape or in a dense shape, for example. The outer shape of the microlens 15 may be circular in a plan view, or rectangular in a plan view, for example. In each microlens 15, the height from the interface between the resin layer 14 and the glass substrate 12 to the apex position of the microlens 15 may be, for example, 50 μm, the radius of curvature may be, for example, 30 μm, and the amount of sag may be, for example, 25 μm.

In the radiation angle conversion element 10 according to embodiment 1, the resin layer 14 is provided in the central portion on the one main surface of the glass substrate 12, and the portion 18 where the resin layer 14 is not provided on the one main surface of the glass substrate 12 is present outside thereof. That is, in the radiation angle conversion element 10, the resin layer 14 is not formed over the entire one main surface of the glass substrate 12, and the portion 18 where the surface of the glass substrate 12 is exposed exists around the resin layer 14. When the radiation angle conversion element 10 is mounted on the housing, the exposed portion 18 of the surface of the glass substrate 12 serves as a joint portion 18 for joining the radiation angle conversion element 10 to the housing.

The width of the glass substrate 12 is set to L₀The width of the connecting portion 18 is set to L₁When L is₁And L₀Has a relationship of 0.01L₀≦L₁≦0.3L₀Preferably 0.05L₀≦L₁≦0.2L₀More preferably 0.1L₀≦L₁≦0.15L₀. If L is₁Ratio of 0.01L₀If the thickness is small, a connection area for obtaining sufficient adhesive strength and sealing property cannot be obtained. On the other hand, if L₁Ratio of 0.3L₀Large, too large area of the connecting portion, and small size of the elementThe patterning creates a barrier.

Fig. 4 is a schematic cross-sectional view showing a light-emitting device 20 using the radiation angle conversion element 10 according to embodiment 1 of the present invention. The light emitting device 20 includes a case 22, a light emitting element 24, and an emission angle changing element 10.

The housing 22 is formed of ceramic and has a box shape with an open upper surface. A light emitting element 24 is fixed to the bottom surface 22a of the case 22. As the light emitting element 24, in addition to a surface emitting laser (VCSEL), an FP type semiconductor laser, a Light Emitting Diode (LED), a solid laser such as YAG, a gas laser such as excimer laser, or a discharge lamp such as a metal halide lamp may be used.

The radiation angle conversion element 10 is joined to the case 22 in a capping manner, whereby a space in which the light emitting element 24 is provided is sealed. The radiation angle conversion element 10 is provided so that the surface on which the microlens array 16 is formed faces the light emitting element 24 side. In the light-emitting device 20 formed in this manner, light emitted from the light-emitting element 24 is diffused by the microlenses 15 of the microlens array 16, and is emitted to the outside through the glass substrate 12. The glass substrate 12 is also referred to as cover glass in the sense that it serves not only as a base material for the microlens array 16 but also to protect the light-emitting elements 24. The use of glass is advantageous from the side of mechanical strength and scratch resistance.

Fig. 5 is an enlarged view of a joint portion C of the radiation angle changing element 10 and the housing 22 shown in fig. 4. A step portion 22b for engaging the radiation angle conversion element 10 is formed at an opening edge portion of the case 22. The step portion 22b of the case 22 and the joining portion 18 of the radiation angle changing element 10 are joined by an adhesive 23.

Here, in the radiation angle conversion element 10 of the present embodiment, since the resin layer 14 is not provided at the joint portion 18 and the glass substrate 12 is exposed, the joint between the glass and the ceramic is not the joint between the resin and the ceramic as shown in fig. 2. Therefore, the adhesion is improved compared with the case of bonding the resin and the ceramic, and the case 22 to which the light emitting element 24 is fixed can be firmly bonded.

In addition, since the difference in thermal expansion coefficient between the glass and ceramic is smaller than that between the resin and ceramic, the resistance to thermal shock can be improved.

Fig. 6 (a) and (b) are views for explaining the radiation angle conversion element 30 according to embodiment 2 of the present invention. Fig. 6 (a) is a plan view of the radiation angle changing element 30. Fig. 6 (b) is a sectional view a-a of the radiation angle changing element 30 shown in fig. 3 (a).

The radiation angle conversion element 30 according to embodiment 2 is different from the radiation angle conversion element 10 according to embodiment 1 in that a metal film 32 is formed on one main surface of the glass substrate 12 at the bonding portion 18 outside the resin layer 14.

The metal film 32 may be a single-layer film made of one metal or an alloy of a plurality of metals, or may be a multilayer film in which a plurality of metal films made of a single metal are stacked. As the kind of metal constituting the metal film 32, Cr, Ni, Pt, Ti, Pd, Au, and the like are used, but not limited thereto. As an example of the case of forming a multilayer film, there is a multilayer film in which Cr, Ni, and Au are formed in this order from the glass substrate 12 side. The thickness of the metal film 32 may be, for example, 0.5 μm.

The width of the glass substrate 12 is set to L₀The width of the connecting portion 18 is set to L₁The width of the metal film 32 is L₂When L is₀、L₁And L₂Has a relationship of L₁＝L₂、0.01L₀≦L₂≦0.3L₀Preferably 0.05L₀≦L₂≦0.2L₀More preferably 0.1L₀≦L₂≦0.15L₀. If L is₂Ratio of 0.01L₀If the bonding area is small, the bonding area by the solder 44 cannot be sufficiently obtained, and it may be difficult to obtain a strong bonding strength. On the other hand, if L₂Ratio of 0.3L₀If the size is large, the area of the connection portion becomes too large, which hinders the miniaturization of the device.

Fig. 7 is a schematic cross-sectional view showing a light-emitting device 40 using a radiation angle conversion element 30 according to embodiment 2 of the present invention. The light emitting device 40 also includes a ceramic case 22, a light emitting element 24, and an emission angle changing element 30.

Fig. 8 is an enlarged view of a joint portion C of the radiation angle changing element 30 and the housing 22 shown in fig. 7. As shown in fig. 8, a stepped portion 22b for joining the radiation angle conversion element 30 is formed at an opening edge portion of the case 22, and a metal film 42 is formed on the stepped portion 22 b. The metal film 42 can be formed by plating, vapor deposition, or the like.

As described above, in the radiation angle conversion element 30 according to embodiment 2, the metal film 32 is formed on the glass substrate 12 at the bonding portion 18. Therefore, the metal film 32 on the radiation angle conversion element 30 side and the metal film 42 on the case 22 side can be joined by the solder 44, and therefore, a strong joining strength can be obtained.

Fig. 9 (a) and (b) are views for explaining the radiation angle conversion element 50 according to embodiment 3 of the present invention. Fig. 9 (a) is a plan view of the radiation angle changing element 50. Fig. 9 (b) is a sectional view a-a of the radiation angle changing element 50 shown in fig. 9 (a).

The radiation angle conversion element 50 according to embodiment 3 is different from the radiation angle conversion element 10 according to embodiment 1 in that a metal film 32 is formed on the outer side of a resin layer 14 at a joint portion 18, and an exposed portion 52 of a glass substrate 12 is provided on the outer side of the metal film 32. In other words, in the radiation angle conversion element 50 according to embodiment 3, the metal film 32 is formed only on the inner side of the bonding portion 18, and the surface of the glass substrate 12 on the outer side is exposed. In the joint portion 18, the ratio of the area of the metal film 32 to the area of the exposed portion 52 may be 5: 1-1: 5.

the width of the glass substrate 12 is set to L₀The width of the connecting portion 18 is set to L₁The width of the metal film 32 is L₂The width of the exposed part 52 is set to L₃When L is₀、L₁、L₂And L₃Has a relationship of L₁＝L₂+L₃、0.01L₀≦L₂+L₃≦0.3L₀Preferably 0.05L₀≦L₂+L₃≦0.2L₀More preferably 0.1L₀≦L₂+L₃≦0.15L₀. If L is₂+L₃Ratio of 0.01L₀If the thickness is small, a connection area for obtaining sufficient adhesive strength and sealing property cannot be obtained. On the other hand, if L₂+L₃Ratio of 0.3L₀If the size is large, the area of the connection portion becomes too large, which hinders the miniaturization of the device. Further, L₂And L₃The following may be satisfied. 0.01L₂≦L₃≦10L₂Preferably 0.05L₂≦L₃≦L₂More preferably 0.10L₂≦L₃≦0.5L₂. If L is₃Ratio of 0.01L₂If the thickness is small, it may be difficult to obtain a sufficient tolerance during cutting. On the other hand, if L₃Than 10L₂If the bonding area is large, the bonding area by the solder 44 cannot be sufficiently obtained, and it may be difficult to obtain a strong bonding strength.

The metal film 32 may be a single-layer film made of one metal or an alloy of a plurality of metals, or may be a multilayer film in which a plurality of metal films made of a single metal are stacked. As the kind of metal constituting the metal film 32, Cr, Ni, Pt, Ti, Pd, Au, and the like are used, but not limited thereto. As an example of the case of forming a multilayer film, there is a multilayer film in which Cr, Ni, and Au are formed in this order from the glass substrate 12 side. The thickness of the metal film 32 may be, for example, 0.5 μm.

In general, the radiation angle conversion element is manufactured by preparing a glass substrate larger than a formation region of a microlens array, molding the microlens array on at least one main surface, and then cutting the glass substrate to have a predetermined size. The method is a method of forming a plurality of radiation angle conversion elements on at least one surface of a large glass substrate and cutting out the respective radiation angle conversion elements. As a method for cutting a glass substrate, there are a method using a rotating grindstone, a method of cutting by laser, a method of mechanically cutting a glass substrate by scribing with diamond or the like a glass cutter, and the like. In the case of the method of cutting using a rotating grindstone of a glass substrate, if a resin layer is present in the cut portion, the resin layer comes into contact with the grindstone rotating at a high speed, and a phenomenon in which the resin layer constituting the microlens array is peeled off from the portion may be observed. In the case of the method of cutting with a laser, if a resin layer or a metal film is present in a cut portion of a glass substrate, the resin layer or the metal film is also irradiated with the laser at the time of laser irradiation, and a part of a microlens formed in the resin layer may melt or evaporate, and this part may become a defect. Further, in the case of a method of mechanically cutting a glass substrate after scribing with diamond or the like, if a resin layer or a metal film is present in a cut portion, the glass substrate thereunder is less likely to be scribed, and as a result, a cutting failure is likely to occur.

In the radiation angle conversion element 50 according to embodiment 3, since the exposed portion 52 of the glass substrate 12 is formed outside the metal film 32 of the bonding portion 18, the grinding stone, the laser irradiation, or the blade tip directly acts on the glass substrate 12. As a result, the metal film 32 or the resin layer 14 is not damaged, and thus generation of defective products and the like due to reduction in yield or mixing of foreign matter during the cutting operation can be suppressed.

Next, a method for manufacturing the radiation angle conversion element will be described. However, the following description does not limit the method for manufacturing the radiation angle conversion element of the present invention.

The radiation angle changing element can be manufactured by a so-called step and repeat method. The step and repeat method is a method of forming a structure on the entire surface of a substrate by forming the structure partially on the substrate using a mold having a predetermined size and repeating molding while shifting the molding position. As for the steps of this method, for example, Japanese patent application laid-open Nos. 2014-188869, 2014-13902, 2010-24470, 2010-80632, 2008-168641, 2007-103924, 2007-103103924, 2006-1032458072, and the like are cited as references.

In a method of forming a structure such as a microlens on a substrate, a mold (mold) smaller than a glass substrate is prepared, a work having a photocurable resin layer is aligned with the mold (a predetermined lens shape is formed on the surface) on the glass substrate, a resin is filled between the mold and the work, and the resin is cured by irradiating ultraviolet light to the portion. In this case, the ultraviolet light is irradiated only directly below the mold. By sequentially performing such transfer in the glass substrate, a predetermined pattern can be formed on the entire surface of the glass substrate.

There are various methods for manufacturing the mold. For example, a mold in which a lens shape is formed by machining a metal such as Ni, a mold in which a lens shape made of a photosensitive resin is formed on a glass or semiconductor substrate by photolithography, a mold which is transferred from these molds by plating, and a mold obtained by molding a photosensitive resin using these molds can be used. In the following example of the manufacturing method, a metal mold is used, in which a resist pattern of a microlens array is formed by laser drawing and then electroforming is performed.

Fig. 10 (a) to (g) show an example of a manufacturing process of the radiation angle conversion element. First, as shown in fig. 10 (a), a predetermined amount of ultraviolet curable resin 60 is dropped onto a predetermined position on one main surface of the prepared glass substrate 12. Next, as shown in fig. 10 (b), the position of the mold (die) 62 is aligned on a plane parallel to the main surface of the glass substrate 12. Next, as shown in fig. 10 (c), the mold 62 is pressed so that the ultraviolet curable resin 60 is filled between the glass substrate 12 and the mold 62. While pressing the mold 62, ultraviolet rays are irradiated to a predetermined region at an irradiation size corresponding to the size of the mold 62. Next, as shown in fig. 10 (d), the mold 62 is released. Next, as shown in fig. 10 (e), the steps of fig. 10 (a) to 10 (d) are repeated while changing the position on the glass substrate 12. By repeating these steps, as shown in fig. 10 (f), a plurality of radiation angle conversion elements are formed on the entire surface of the glass substrate 12. If necessary, heat treatment may be performed thereafter. Further, a mold-releasing treatment may be performed in the mold 62. Finally, as shown in fig. 10 (g), the glass substrate 12 is cut to obtain the radiation angle conversion element 10 shown in fig. 3 (a) and (b).

Fig. 11 (a) to (g) show an example of another manufacturing process of the radiation angle conversion element. The manufacturing process differs from the manufacturing processes shown in fig. 10 (a) to (g) in that the metal film 32 is patterned in advance on a part of the glass substrate 12 before the radiation angle conversion element is formed. In this case, since the pattern of the metal film 32 also functions as a light-shielding film when the ultraviolet rays are irradiated, there is an advantage that the ultraviolet curable resin 60 oozing out of the mold 62 is not cured. If the mold 62 is made of a translucent material, ultraviolet rays can be irradiated from the back side of the mold, and the metal film 32 can be overlapped with a part of the ultraviolet curable resin 60. As shown in fig. 11 (g), the glass substrate 12 is cut to obtain the radiation angle conversion element 30 shown in fig. 6 (a) and (b).

Fig. 12 (a) to (g) show an example of another manufacturing process of the radiation angle conversion element. The process for forming the metal film 32 in advance on a part of the glass substrate 12 before forming the radiation angle conversion element is the same as the process for producing the glass substrate 12 shown in fig. 11 (a) to (g), but the process for producing the glass substrate is different from the process for producing the glass substrate 12 shown in fig. 11 (a) to (g) in that a part where the metal film 32 is not formed (a part where the surface of the glass substrate 12 is exposed) is formed in advance on the outer side of the metal film 32. As shown in fig. 12 (g), the exposed portion of the glass substrate 12 outside the metal film 32 is cut to obtain the radiation angle conversion element 50 shown in fig. 9 (a) and (b).

In the above-described manufacturing process, an example in which an appropriate amount of the ultraviolet curable resin 60 is dropped onto the glass substrate 12 and aligned with the mold 62 is shown, but conversely, the uncured ultraviolet curable resin 60 may be dropped onto the mold 62 and aligned with the glass substrate 12.

Further, before cutting the glass substrate 12, an antireflection coating (AR coating) may be applied to the front surface of the microlens array 16, the back surface of the glass substrate 12 (the surface on which the microlens array 16 is not formed), or both.

As a method for patterning the metal film 32 on the glass substrate 12, there is a method in which a metal film is formed by a plating method, a sputtering method, a vapor deposition method, or the like, a resist pattern is formed thereon by a photolithography method, and an unnecessary metal film is removed by etching using the resist pattern as a mask. Alternatively, there is a method (lift-off method) in which a resist pattern is formed on the glass substrate 12 in advance before forming the metal film, and after forming the metal film thereon, the resist and the metal film formed thereon are removed.

The type of the metal film 32 is appropriately selected in consideration of adhesion to glass, sealing property, adhesion to a sealing material, and the like. In some cases, the metal layer is composed of a single metal, and a multilayer film may be formed in consideration of adhesion of each portion. For example, a 3-layer film in which Cr, Ni, and Au are formed in this order from the glass substrate 12 side is used, but the combination of metals is not limited to this, and can be selected from various metal films and metal films obtained by combining these.

The present invention has been described above based on the embodiments. It will be understood by those skilled in the art that these embodiments are illustrative, and various modifications are possible in combination of the respective constituent elements and the respective processing steps, and such modifications are also within the scope of the present invention.

Industrial applicability

The present invention can be used for a radiation angle conversion element that converts the radiation angle of an incident beam.

Description of the reference numerals

10. 30, 50: radiation angle changing element, 12: glass substrate, 14: resin layer, 15: microlens, 16: microlens array, 18: engaging portion, 20, 40: light-emitting device, 22: a housing, 24: light-emitting element, 32, 42: metal film, 52: exposed portion, 60: ultraviolet curable resin, 62: and (5) molding.