Surface light emitting device, lens laminate, method of manufacturing the same, method of manufacturing surface light emitting device, and method of manufacturing lens aggregate

Abstract

To provide a surface light emitting device, etc., which reduces luminance nonuniformity.SOLUTION: A lens laminate 1 comprises: a first lens aggregate 10 including a first base part 11 which is opposed with a plurality of light sources 32 on a bottom face thereof and a plurality of first lens parts 12 positioned on the first base part 11 and having a first central axis 13 which coincides with each light axis 33 of the plurality of light sources 32; and a second lens aggregate 20 including a second base part 21 which is opposed with the first lens aggregate 10 on a bottom face thereof and a plurality of second lens parts 22 positioned on the second base part 21 and having a second central axis 23 which coincides with the first central axis 13 of the plurality of first lens parts 12. The plurality of first lens parts 12 has a circular outer periphery in a top view, has a first flat face 14 of a top face and is disposed in such a manner that the outer peripheries of the adjacent first lens parts 12 are in contact with each other. An outer periphery of the second lens part 22 is circular in a top view, and the adjacent second lens parts 22 are disposed so as to be separated via a connection plane that is a second flat face 24.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present disclosure relates to a surface emitting device, a lens laminate and a method for manufacturing the same, a method for manufacturing a surface emitting device, and a method for manufacturing a lens assembly. [Background technology]

[0002] 2. Description of the Related Art A surface light emitting device including a plurality of LEDs and a plurality of lenses is known. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 9-505412 [Patent Document 2] Japanese Patent Application Laid-Open No. 2008-003604 Summary of the Invention [Problem to be solved by the invention]

[0004] One object of one aspect of the present disclosure is to provide a surface-emitting device, a lens laminate and a manufacturing method thereof, a manufacturing method for a surface-emitting device, and a manufacturing method for a lens assembly, in which brightness unevenness is reduced. Another object of another aspect is to provide a surface-emitting device, a lens laminate and a manufacturing method thereof, a manufacturing method for a surface-emitting device, and a manufacturing method for a lens assembly, in which productivity is improved. Note that the description of these objects does not preclude the existence of other objects. Furthermore, it is not necessary for one aspect of the present disclosure to solve all of these objects. Furthermore, it is possible to extract other objects from the description of the specification, drawings, and claims of the present disclosure. [Means for solving the problem]

[0005] A surface-emitting device according to one embodiment of the present disclosure is a surface-emitting device comprising a plurality of light sources and a lens stack arranged above the plurality of light sources, wherein the lens stack comprises: a first lens assembly having a first base portion facing the plurality of light sources from below; and a plurality of first lens portions located on the first base and having a first central axis coinciding with each optical axis of the plurality of light sources; and a second lens assembly having a second base portion facing the first lens assembly from below; and a plurality of second lens portions located on the second base and having a second central axis coinciding with the first central axes of the plurality of first lens portions, wherein the plurality of first lens portions have circular outer peripheries in a top view and a first flat top surface, and are arranged so that the outer peripheries of adjacent first lens portions are in contact with each other; and the second lens portions have circular outer peripheries in a top view, and adjacent second lens portions are arranged so that they are spaced apart via a connecting surface which is a second flat surface.

[0006] Another aspect of the present disclosure provides a lens stack for placement above a plurality of light sources, comprising: a first lens assembly having a first base for facing the plurality of light sources from below; and a plurality of first lens portions located on the first base and having a first central axis for aligning with each optical axis of the plurality of light sources; and a second lens assembly having a second base for facing the first lens assembly from below; and a plurality of second lens portions located on the second base and having a second central axis for aligning with the first central axes of the plurality of first lens portions, wherein the plurality of first lens portions have circular outer peripheries in a top view and a first flat top surface, and are arranged so that the outer peripheries of adjacent first lens portions are in contact with each other; and the second lens portions have circular outer peripheries in a top view, and adjacent second lens portions are arranged so that they are spaced apart via a connecting surface which is a second flat surface.

[0007] Furthermore, a manufacturing method of a lens laminate according to another aspect of the present disclosure includes a mold preparation step of preparing a first mold having a plurality of first recesses, each having a circular periphery in top view and a first flat surface at the bottom, where the peripheries of adjacent first recesses are arranged in contact with each other, and a second mold having second recesses, each having a circular periphery in top view, where the peripheries of adjacent second recesses are arranged apart from each other, and a second flat surface surrounding the peripheries of the second recesses; a molding step of using the first mold to mold a first lens assembly including a first base and a plurality of first lens portions located on the first base; The method includes the steps of abutting a first pin against the top surface of the first lens portion molded in the first recess, which is molded in the first flat portion of the first recess, to release the first lens assembly from the first mold; molding a second lens assembly using the second mold, which includes a second base and a plurality of second lens portions arranged on the second base; abutting a second pin against the connecting surface molded in the second flat portion of the second recess, to release the second lens assembly from the second mold; and placing the second lens assembly released from the second mold on the first lens assembly released from the first mold.

[0008] Furthermore, a manufacturing method for a lens assembly according to another aspect of the present disclosure includes a first mold preparation step of preparing a first mold having a plurality of first recesses, each having a circular outer periphery when viewed from above and a first flat surface at the bottom, where the outer peripheries of adjacent first recesses are arranged in contact with each other; a step of using the first mold to mold a first lens assembly comprising a first base and a plurality of first lens portions positioned on the first base; and a step of abutting a first pin against the top surface of the first lens portion molded in the first recess, which is molded by the first flat surface of the first recess, to release the first lens assembly from the first mold. [Effects of the Invention]

[0009] According to the surface emitting device according to the embodiment of the present disclosure, it is possible to reduce uneven brightness. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a top view showing a surface emitting device according to a first embodiment. [Figure 2] 2 is a perspective view with an enlarged view of a main part of the surface light emitting device of FIG. 1. [Figure 3] FIG. 2 is a cross-sectional view taken along line III-III in FIG. [Figure 4] FIG. 4 is an exploded enlarged cross-sectional view of a main part of FIG. 3. [Figure 5] FIG. 2 is an exploded perspective view of the surface light emitting device of FIG. [Figure 6] 2 is an enlarged cross-sectional view showing emitted light when the surface light emitting device of FIG. 1 is turned on. FIG. [Figure 7] FIG. 1 is a schematic cross-sectional view showing a surface light-emitting device. [Figure 8] FIG. 10 is a schematic cross-sectional view showing a surface light source device according to the prior art. [Figure 9] FIG. 10 is a cross-sectional view showing a step of preparing a first mold. [Figure 10] FIG. 10 is a cross-sectional view showing a step of placing resin in a first mold. [Figure 11] FIG. 10 is a cross-sectional view showing a step of opening the first mold. [Figure 12] FIG. 10 is a cross-sectional view showing a step of releasing from the first mold. [Figure 13] FIG. 10 is a cross-sectional view showing a step of preparing a second mold. [Figure 14] FIG. 10 is a cross-sectional view showing a step of placing resin in a second mold. [Figure 15] FIG. 10 is a cross-sectional view showing the step of opening the second mold. [Figure 16] FIG. 10 is a cross-sectional view showing the step of releasing from the second mold. [Figure 17] FIG. 10 is a schematic cross-sectional view showing a surface emitting device according to a second embodiment. [Figure 18] FIG. 10 is a schematic cross-sectional view showing a surface emitting device according to a third embodiment. [Figure 19] FIG. 10 is a schematic cross-sectional view showing a surface emitting device according to a fourth embodiment. [Figure 20] FIG. 10 is a schematic cross-sectional view showing a surface emitting device according to a fifth embodiment. [Figure 21] FIG. 2 is a schematic top view of the light-emitting module. [Figure 22] 22 is a schematic top view of the light-emitting module of FIG. 21 with a first lens assembly disposed therein. FIG. [Figure 23] FIG. 23 is a schematic cross-sectional view taken along line XXIII-XXIII in FIG. 22. [Figure 24] FIG. 2 is a schematic cross-sectional view showing an example of a light source. [Figure 25] FIG. 10 is a schematic cross-sectional view showing a surface emitting device according to a sixth embodiment. [Figure 26] 1 is a schematic cross-sectional view showing a surface emitting device according to Comparative Example 1. FIG. [Figure 27] 10 is a schematic cross-sectional view showing a surface emitting device according to Comparative Example 2. FIG. [Figure 28] FIG. 10 is a schematic cross-sectional view showing a surface emitting device according to Comparative Example 3. [Figure 29] 10 is a schematic cross-sectional view showing a surface emitting device according to Comparative Example 4. FIG. [Figure 30] 4 is an image diagram showing a simulation result of the luminance distribution of the surface light emitting device according to Example 1. FIG. [Figure 31] 10 is an image diagram showing a simulation result of the luminance distribution of the surface light emitting device according to Comparative Example 1. FIG. [Figure 32] 10 is an image diagram showing a simulation result of the luminance distribution of the surface light emitting device according to Comparative Example 2. FIG. [Figure 33] 10 is an image diagram showing a simulation result of the luminance distribution of the surface light emitting device according to Comparative Example 3. FIG. [Figure 34] 10 is an image diagram showing a simulation result of the luminance distribution of the surface light emitting device according to Comparative Example 4. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, each embodiment of the present disclosure will be described with reference to the drawings. In the following description, terms indicating specific directions or positions (e.g., "upper," "lower," and other terms including these terms) may be used as necessary. However, the use of these terms is intended to facilitate understanding of the invention with reference to the drawings, and the meaning of these terms does not limit the technical scope of the present disclosure. Furthermore, parts with the same reference numerals appearing in multiple drawings indicate the same or equivalent parts or components.

[0012] Furthermore, the embodiments described below are illustrative examples of the technical concepts of the present disclosure and are not intended to limit the present disclosure. Furthermore, unless otherwise specified, the dimensions, materials, shapes, relative positions, etc. of the components described below are intended for illustrative purposes only and are not intended to limit the scope of the present disclosure. Furthermore, the content described in one embodiment or example may also be applicable to other embodiments or examples. Furthermore, the size and positional relationships of components shown in the drawings may be exaggerated for clarity. In addition, to avoid overly complex drawings, schematic diagrams may be used in which some elements are omitted, or end views showing only the cut surface may be used as cross-sectional views. On the other hand, for materials whose form changes during processing, such as resin materials, for example, materials that are liquid before curing and solid after curing, the same reference numerals are used both before and after curing.

[0013] [Embodiment 1] 1 to 7 show a surface emitting device 100 according to a first embodiment. In these figures, Fig. 1 is a top view showing the surface emitting device 100 according to the first embodiment, Fig. 2 is a perspective view with an enlarged view of a main part of the surface emitting device 100 of Fig. 1, Fig. 3 is a cross-sectional view taken along line III-III of Fig. 1, Fig. 4 is an enlarged cross-sectional view of a main part obtained by disassembling Fig. 3, Fig. 5 is an exploded perspective view of the surface emitting device 100 of Fig. 1, Fig. 6 is an enlarged cross-sectional view showing emitted light when the surface emitting device 100 of Fig. 1 is turned on, and Fig. 7 is a schematic cross-sectional view showing the surface emitting device 100. As shown in Figs. 1 to 5, the surface emitting device 100 includes a lens laminate 1, a light-emitting module 30 including a plurality of light sources 32, and a housing 40.

[0014] (Housing 40) The housing 40 is a member capable of supporting the lens stack 1 and the light source 32. In the example of Fig. 2 and Fig. 3, the housing 40 supports the light emitting module 30 including a plurality of light sources 32, and the lens stack 1. The housing 40 supports the lens stack 1 above the light emitting module 30 so that the lens stack 1 is disposed at a distance from the light emitting module 30.

[0015] The housing 40 includes a base 41 including a first top surface, and a wall 42 arranged to surround the first top surface of the base 41. The light-emitting module 30 is arranged on the first top surface. The wall 42 includes a top surface and a second top surface 43 located between the first top surface and the top surface. The outer edge portion of the lens laminate 1 is arranged on the second top surface. The distance (height) between the first top surface and the second top surface is selected appropriately depending on the light distribution characteristics of each light source of the light-emitting module 30, etc.

[0016] The first upper surface is large enough to accommodate the light-emitting module 30. The second upper surface is sufficient to support the lens laminate 1. For example, it may be disposed around the entire periphery of the first upper surface in a top view, or may be disposed partially around the first upper surface. When the second upper surface is disposed partially, it is preferably disposed at a position sandwiching the light-emitting module 30 in a top view. The top surface is a portion located outside the second upper surface in a top view. The distance (height) between the second upper surface and the top surface is preferably set to a height that allows the top surface to be positioned above the lens laminate 1, as shown in FIG. 3. The housing 40 can be formed of one member or a composite including two or more members. For example, the base 41 and the wall 42 may be formed of an integral member or separate members. The housing 40 can be formed of a resin or a metal. Furthermore, the housing 40 is preferably formed of a member with high reflectivity for light emitted from the light-emitting module 30.

[0017] (Light emitting module 30) The light emitting module 30 includes a substrate 31 and a plurality of light sources 32 arranged on the substrate 31. The light emitting module 30 is arranged below the lens laminate 1 as shown in FIGS. 2 and 3. One surface emitting device 100 can include one or more light emitting modules 30. Furthermore, if the housing 40 includes wiring or the like, the light sources 32 may be arranged directly in the housing 40 instead of the light emitting modules 30.

[0018] (Substrate 31) The shape of the substrate 31 constituting the light-emitting module 30 in a top view is, for example, rectangular. In the examples of FIGS. 1, 2, and 5, the substrate 31 is square. However, the shape of the substrate 31 is not limited to this and may be rectangular, octagonal, or another polygonal shape. The substrate 31 includes an insulating base material and a conductive member for supplying power to the light-emitting module 30. The substrate 31 may be a rigid substrate or a flexible substrate.

[0019] (Light source 32) A plurality of light sources 32 are arranged in a matrix on the substrate 31. Each light source 32 is composed of a semiconductor light-emitting element such as a light-emitting diode. The light source 32 may also include a light-emitting element and a wavelength conversion member arranged on the light-emitting element. This allows the emitted light color to be adjusted.

[0020] (Lens laminate 1) The lens stack 1 is disposed above the plurality of light sources 32. In the examples of Figs. 3, 5, etc., the lens stack 1 is disposed spaced apart from the upper surface of the substrate 31 on which the plurality of light sources 32 are disposed. In the example of Fig. 3, the second upper surface 43 of the wall portion 42 of the housing 40 is used to separate the lens stack 1 from the light-emitting module 30 at a fixed distance. However, this configuration is not limiting, and the lens stack 1 may also be separated from the light-emitting module 30 by a configuration such as interposing a spacer therebetween.

[0021] As shown in FIGS. 3 to 5, the lens stack 1 includes a first lens assembly 10 and a second lens assembly 20. The lower surface of the first lens assembly 10 faces the light emitting module 30. The second lens assembly 20 is disposed on the upper surface of the first lens assembly 10.

[0022] (First lens assembly 10) The first lens assembly 10 is composed of a first base 11 and a plurality of first lens portions 12 arranged on this first base 11. As shown in Figures 3, 5, etc., the first base 11 is plate-shaped. Each first lens portion 12 is a lens having a first radius of curvature, and has a first central axis 13 that serves as the optical axis of the lens. The first lens portion 12 has a shape, for example, like a hemisphere with the top portion cut off.

[0023] As shown in FIGS. 2 and 5, the outer peripheries of the plurality of first lens portions 12 are each circular when viewed from above. Furthermore, each first lens portion 12 is disposed on the first base portion 11 such that the outer peripheries of adjacent first lens portions 12 are circumscribing each other. That is, one first lens portion 12 is disposed so as to be circumscribing four first lens portions 12. Furthermore, the top surface of each first lens portion 12 is a flat surface as shown in FIG. 4, and this flat surface is referred to as a first flat surface 14. The shape of the first flat surface 14 when viewed from above is circular. The diameter of the first flat surface 14 of each first lens portion 12 is referred to as a first diameter DL1.

[0024] (Second lens assembly 20) The second lens assembly 20 is composed of a second base 21 and a plurality of second lens portions 22 arranged on the second base 21. As shown in FIGS. 2 to 5, the second base 21 is also plate-shaped. The plurality of second lens portions 22 are arranged at regular intervals on the second base 21. The outer periphery of each second lens portion 22 is circular in top view. In the example shown in FIGS. 1 and 2, the plurality of second lens portions 22 are arranged in a matrix on the second base 21. The circular second lens portions 22 are spaced apart from adjacent second lens portions 22. In other words, the entire outer periphery of each second lens portion 22 is surrounded by the flat surface of the second base 21. This area is referred to as a connecting surface or second flat surface 24. Adjacent second lens portions 22 are spaced apart via the connecting surface, which is the second flat surface 24. Each second lens portion 22 is a lens having a second radius of curvature and has a second central axis 23, which is the optical axis of the lens. The entire surface of second lens portion 22 is curved, and is, for example, a part of a sphere. Furthermore, as shown in Figures 2 and 4, the diameter of second lens portion 22 is defined as a second diameter DL2.

[0025] 4 and 6, the first lens assembly 10 and the second lens assembly 20 are arranged so that the optical axis 33 of the light emitted from each light source 32 is aligned with the first central axis 13 of the first lens portion 12 and the second central axis 23 of the second lens portion 22. By stacking the first lens assembly 10 and the second lens assembly 20 in this manner to form a lens stack 1, it is possible to reduce brightness unevenness in the surface emitting device 100.

[0026] Furthermore, it is preferable that the first diameter DL1 of the first flat surface 14, which is the top surface of the first lens portion 12, is the same as or smaller than the second diameter DL2 of the second lens portion 22. By making DL1≦DL2 in this way, it is possible to make the entire first flat surface 14 of the first lens portion 12 overlap with the second lens portion 22 in a top view, as shown in Fig. 2. This makes it possible to make the first outgoing light emitted from the first lens portion 12 incident on the second lens portion 22, thereby reducing loss of light incident on the first lens portion 12 from the light source 32.

[0027] The thickness TL1 of the first lens portion 12 is preferably thicker than the thickness TL2 of the second lens portion 22. With this configuration, the top surface of the first lens portion 12 can stably support the second lens portion 22. The thickness L1 of the first lens portion 12 is the distance from the top surface of the first base portion 11 to the top surface in a direction parallel to the first central axis. Similarly, the thickness TL2 of the second lens portion 22 is the distance from the top surface of the second base portion 21 to the apex of the second lens in a direction parallel to the second central axis.

[0028] Furthermore, it is preferable that the thickness TB1 of the first base portion 11 is thinner than the thickness TL1 of the first lens portion 12. This allows the thickness of the first lens portion 12 to be thin.

[0029] Materials that can be used to form the first lens assembly 10 and the second lens assembly 20 include polycarbonate resin, acrylic resin, cycloolefin polymer (COP), silicone resin, and the like.

[0030] 7, the width PS of light source 32 is preferably 15% to 50% of the diameter PL (maximum width) of first lens portion 12 in a cross section including optical axis 33 of light source 32. With this configuration, it is possible to prevent low-brightness areas from occurring between first lens portions 12. The width of light source 32 refers to the width of the light-emitting surface.

[0031] As shown in Fig. 6, it is preferable that the light emitted from the light source 32 and incident on the first lens assembly 10 be incident at an angle equal to or smaller than the critical angle with respect to the curved surface of the first lens portion 12. This prevents the light incident on the first lens assembly 810 from being totally reflected, as in the conventional surface light source device 800 shown in Fig. 8, and makes it possible to efficiently emit the light toward the second lens assembly 20.

[0032] It is also preferable that the first radius of curvature of first lens portion 12 and the second radius of curvature of second lens portion 22 are the same. This makes it possible to reduce brightness unevenness by making the direction of light emitted from the curved surface of first lens portion 12 and the direction of light emitted from the curved surface of second lens portion 22 approximately the same. This also makes it possible to make it less likely that total reflection, as in surface light source device 800 shown in FIG. 8, or light beam intersection within second lens assembly 820 will occur.

[0033] [Method of manufacturing a surface emitting device] Here, a method for manufacturing the surface emitting device 100 will be described. First, a lens stack 1 is prepared. The lens stack 1 is made by preparing a first lens assembly 10 and a second lens assembly 20, and then stacking them together. The first lens assembly 10 and the second lens assembly 20 can be prepared by manufacturing them using the manufacturing methods for the first lens assembly 10 and the second lens assembly 20 described below. Alternatively, the first lens assembly and the second lens assembly 20 can be prepared by purchasing them.

[0034] The first lens assembly 10 and the second lens assembly 20 can be bonded together via a bonding member. For example, a light-transmitting bonding member is placed on the first lens assembly 10, the second lens assembly 20 is placed on top of that, and the bonding member is cured to bond the first lens assembly 10 and the second lens assembly 20 together. The bonding member can be made of a light-transmitting silicone resin, epoxy resin, or the like. Alternatively, the first lens assembly and the second lens assembly can be bonded together by a direct bonding method such as pressure bonding, welding, surface activated bonding, atomic diffusion bonding, or hydroxyl bonding without using a bonding member. Heat welding or ultrasonic welding can also be used for welding. Alternatively, the first lens assembly 10 and the second lens assembly 20 can be simply stacked on top of each other without being bonded together. In this case, the first lens assembly 10 and the second lens assembly 20 can be supported by the housing 40 by being fixed with screws or the like or by being bonded with a bonding member.

[0035] Meanwhile, a plurality of light sources 32 are prepared. For example, a plurality of light sources 32 are arranged on a substrate 31. The steps of preparing the lens laminate 1 and the light sources 32 may be performed in reverse order, or may be performed simultaneously. The light sources 32 may be prepared by manufacturing using a known method, or may be purchased.

[0036] Next, the lens stack 1 is placed on the light sources 32. Here, positioning is performed so that the first central axis 13 of the first lens portion 12 and the second central axis 23 of the second lens portion 22 coincide with the optical axis 33 of each light source 32. In this way, a surface emitting device 100 including the lens stack 1 and a plurality of light sources 32 is obtained.

[0037] [Method of manufacturing first lens assembly] Next, a method for manufacturing the first lens assembly 10 will be described with reference to FIGS.

[0038] First, in a first mold preparation step, a first mold 60 is prepared. FIG. 9 shows the first mold 60 in an opened state. The first mold 60 shown in this figure includes a first upper mold 61 and a first lower mold 62. Here, the first lens assembly 10 is molded upside down. That is, the first base portion 11 side of the first lens assembly 10 is molded using the first upper mold 61, and the first lens portion 12 side of the first lens assembly 10 is molded using the first lower mold 62. The first lower mold 62 has a plurality of first recesses 63. Each first recess 63 has a circular outer periphery in a top view. A first flat portion 64, which is the bottom surface that defines the first recess 63, is a surface that corresponds to the first flat surface 14, which is the top surface of the first lens portion. The plurality of first recesses 63 are arranged such that the outer peripheries of adjacent first recesses 63 are in contact with each other.

[0039] Furthermore, the first lower mold 62 includes a plurality of first pins 66 for ejection. Each first pin 66 is disposed so as to be able to protrude into a first cavity 65 formed between the first lower mold 62 and the first upper mold 61. The first pins 66 constitute part of the first flat surface 64. The first pins 66 are disposed so as to protrude from the first flat surface 64 of the first lower mold 62. Of the multiple first recesses 63, the first pins 66 may be disposed in all or some of the first recesses 63. When disposing first pins 66 in some of the first recesses 63, the first pins 66 may be disposed in adjacent first recesses 63, or the first recesses 63 with and without first pins 66 may be disposed alternately. Alternatively, the first recesses 63 may be disposed in the first recesses 63 located at the center and the first recesses 63 located at the corners in a plan view across the entire first lower mold 62. By disposing the first pins 66, which are ejection pins, at an appropriate distance from each other in this manner, it is possible to disperse stress applied when the first lens assembly 10 is released from the first mold 60. As shown in FIG. 9 and other figures, the first pins 66 may be arranged not only in the first recessed portion 63 but also in the first flat portion of the first lower mold 62 located on the edge of a plurality of first recessed portions 63 .

[0040] The first upper mold 61 has a recess for molding the first base portion 11 of the first lens assembly 10. One recess of the first upper mold 61 is formed by a first upper mold step portion 67, and is sized to overlap with the multiple first recesses 63 of the first lower mold 62 in a top view. The lower surface of the first upper mold 61 may be a flat surface without a recess. In that case, the first lower mold 62 has a recess shaped with one large recess and two bottom surfaces of different heights that define the recess and have multiple first recesses 63 recessed from the bottom surface.

[0041] Next, the first lens assembly 10 is molded by transfer molding, compression molding, or injection molding using this first mold 60. In the case of transfer or injection molding, as shown in Fig. 10 , the first mold 60 is closed, a first cavity 65 is formed between the first lower mold 62 and the first upper mold 61, and an uncured first resin material that will form the first lens assembly 10 is placed in this first cavity 65. In the case of compression molding, the uncured resin is placed in the recess of the first lower mold 62, and then the mold is closed. Furthermore, in the case of compression molding, as described above, the first lower mold 62 is used that has a recess shaped with two bottom surfaces of different heights such that one large recess and a plurality of first recesses 63 are recessed from the bottom surface that defines the recess.

[0042] The first resin material is, for example, a silicone resin. In this state, the first resin material is cured. Here, a predetermined curing time is waited for. In this manner, a first lens assembly 10 including a first base 11 and a plurality of first lens portions 12 positioned on this first base 11 is molded.

[0043] The first lens assembly 10 is then released from the first mold 60. First, as shown in FIG. 11 , the first upper mold 61 and the first lower mold 62 are separated to open the first mold 60. Next, as shown in FIG. 12 , the first pin 66 is protruded to push out the hardened first lens assembly 10. In particular, mold release can be easily achieved by having the first pin 66 abut against the first flat surface 14, which is the top surface formed by the first flat portion 64, of the first lens portion 12 molded in the first recess 63 of the first lower mold 62. In this way, providing a flat region on the first lens assembly 10 ensures an area against which the ejection pin can be pressed during mold release, providing the advantage of facilitating manufacturing.

[0044] [Method of manufacturing the second lens assembly 20] Next, a method for manufacturing the second lens assembly 20 will be described with reference to FIGS.

[0045] First, a second mold 70 is prepared. FIG. 13 shows the second mold 70 in an opened state. The second mold 70 also includes a second upper mold 71 and a second lower mold 72. Like the first mold 60, this second mold 70 also molds the second lens assembly 20 upside down. That is, the second upper mold 71 molds the second base portion 21 side of the second lens assembly 20, and the second lower mold 72 molds the second lens portion 22 side of the second lens assembly 20. The second lower mold 72 has a plurality of second recesses 73. Each second recess 73 has a circular outer periphery in a top view. The outer peripheries of adjacent second recesses 73 are spaced apart from each other. Furthermore, the second lower mold 72 is provided with a second flat portion 74 that surrounds the entire outer periphery of the second recess 73.

[0046] The diameter of the second flat portion 74 of the second recess 73 of the second mold 70 is preferably larger than the depth of the second recess 73. This makes it possible to reduce the thickness of the second lens and thereby make the surface emitting device thinner.

[0047] Furthermore, the opening diameter of the second recess 73 of the second mold 70 is preferably the same as or larger than the diameter of the first recess 63 of the first mold 60. With this configuration, it is possible to make it easier for the first outgoing light emitted from the first lens portion 12 to enter the second lens portion 22.

[0048] The second lower mold 72 is equipped with a plurality of second pins 76 for ejection. Each second pin 76 is also arranged so as to be able to protrude into a second cavity 75 formed at the interface between the second lower mold 72 and the second upper mold 71. The second pins 76 are arranged not in the second recesses 73 but on the second flat surfaces 74. In particular, the second pins 76 are arranged so as to protrude from some of the plurality of second flat surfaces 74. Preferably, among the plurality of second flat surfaces 74, the second flat surfaces 74 on which the second pins 76 are arranged are not adjacent second flat surfaces 74 but second flat surfaces 74 that are spaced apart. By arranging the ejection pins at an appropriate distance, it is possible to distribute the stress applied when the second lens assembly 20 is released from the second mold 70.

[0049] The second upper mold 71 has a recess for molding the second base portion 21 of the second lens assembly 20. One recess in the second upper mold 71 is formed by a second upper mold step portion 77, and is sized to overlap with the multiple second recesses 73 in the second lower mold 72 in a top view. The lower surface of the second upper mold 71 may be a flat surface without a recess. In that case, the second lower mold 72 has a recess shaped with one large recess and two bottom surfaces of different heights that define the recess and have multiple second recesses 73 recessed from the bottom surface.

[0050] Next, the second lens assembly 20 is molded by transfer molding, compression molding, or injection molding using this second mold 70. In the case of transfer molding or injection molding, as shown in FIG. 14 , the second mold 70 is closed, a second cavity 75 is formed between the second lower mold 72 and the second upper mold 71, and an uncured second resin material that constitutes the second lens assembly 20 is placed in this second cavity 75. The same resin as the first resin material can be used for the second resin material. In this state, the second resin material is cured. In this manner, the second lens assembly 20 is molded, which includes the second base 21 and a plurality of second lens portions 22 positioned on this second base 21. In the case of compression molding, the uncured resin is placed in the recess of the second lower mold 72, and then the mold is closed. In the case of compression molding, as described above, the second lower mold 72 used has a recess with a shape that has one large recess and two bottom surfaces of different heights, with multiple second recesses 73 recessed from the bottom surface that defines the recess.

[0051] The second lens assembly 20 is then released from the second mold 70. First, as shown in FIG. 15 , the second upper mold 71 and the second lower mold 72 are separated, and the second mold 70 is opened. Next, as shown in FIG. 16 , the second pin 76 is protruded to push out the hardened second lens assembly 20. In particular, by abutting the second pin 76 against the connecting surface formed by the second flat portion 74 adjacent to the second recess 73 of the second lens portion 22 molded in the second recess 73 of the second lower mold 72, the second lens assembly 20 can be easily released from the second mold 70. In this way, by providing a flat region on the second lens assembly 20, an area can be secured against which the ejection pin can be pressed during release from the mold, which has the advantage of facilitating manufacturing.

[0052] In the above example, the first mold 60 and the second mold 70 are divided into two parts, upper and lower, but it goes without saying that this configuration is not limiting and each mold may be divided into three or more parts.

[0053] [Embodiment 2] In the above example, a lens stack 1 has been described in which one second lens assembly 20 is stacked on the upper surface of a first lens assembly 10. The present disclosure is not limited to this configuration, and for example, the second lens assembly may be configured as an assembly of one or more second sub-lenses that are separate from each other. One such example is shown in FIG. 17 as a surface emitting device according to embodiment 2. In this figure, components similar to those in embodiment 1 described above are given the same reference numerals (however, sub-numbers may be different), and detailed description will be omitted as appropriate.

[0054] 17, the second lens assembly 20B is made up of a plurality of second sub-lenses 20b. Each second sub-lens 20b has one second lens portion 22. When releasing the second sub-lens 20b from the second mold 70 after molding, the second sub-lens 20b having one second lens portion 22 can be released by pressing a push pin against the second flat surface 24 at the corner of the second base portion 21.

[0055] Furthermore, each second sub-lens 20b is fixed to a first flat surface 14 on the upper surface of each first lens portion 12 of the first lens assembly 10. By separating the second lens assembly 20B into each second lens portion 22 in this way, it becomes possible to adjust the fixing position when fixing each second sub-lens 20b to the first lens assembly 10. As a result, there is an advantage in that it is possible to individually adjust the misalignment of the optical axes of the first lens portion 12 and second lens portion 22 included in each first lens assembly 10 and second lens assembly 20B.

[0056] [Embodiment 3] The second lens assembly may also include a plurality of second lens portions. One such example is shown in Fig. 18 as a surface emitting device 300 according to embodiment 3. In this figure, the same components as those in embodiment 1 and the like are denoted by the same reference numerals (however, the sub-numbers may be different), and detailed description thereof will be omitted where appropriate.

[0057] In the surface-emitting device 300 shown in Fig. 18, the second lens assembly 20C is made up of a plurality of second sub-lenses 20c. Here, each second sub-lens 20c has two second lens portions 22 in the direction perpendicular to the plane of the paper in Fig. 18, for a total of four second lens portions 22. The second sub-lens 20c having four second lens portions 22 can be released from the second mold 70 by pressing a push pin against the second flat surface 24 of the connecting surface surrounded by the four second lens portions 22 during release from the mold molding.

[0058] Each second sub-lens 20c is fixed to the top surfaces of four adjacent first lens portions 12 of the first lens assembly 10. By including multiple second lens portions 22 in each of the multiple second sub-lenses 20c in this way, the number of second sub-lenses 20c can be reduced, thereby saving labor for fixing them to the first lens assembly 10. In particular, because misalignment of the optical axes of the first lens portions 12 and the second lens portions 22 is unlikely to occur between adjacent lens portions, a decrease in optical design accuracy is hardly an issue. Furthermore, the number of second lens portions 22 included in the second sub-lens 20c can be two or more.

[0059] [Embodiment 4] Furthermore, the second lens assembly does not necessarily have to include second lens portions in all of the first lens portions. For example, the second lens assembly may be included in only some of the first lens portions. As such an example, a surface emitting device 400 according to a fourth embodiment is shown in FIG. 19. In this figure, the same components as those in the first embodiment and the like described above are designated by the same reference numerals (however, the sub-numbers may be different), and detailed explanations will be omitted where appropriate.

[0060] In the example of the surface-emitting device 400 shown in FIG. 19, the first lens unit 12 includes two types: one with a first flat surface 14 (on the left side in the figure) and one that is hemispherical and does not have a first flat surface 14 (on the right side in the figure). Of these, the second sub-lenses 20b are arranged only on the upper surfaces of the first lens units 12 that have the first flat surfaces 14. With this configuration, it is not necessary to arrange the second sub-lenses 20b on the upper surfaces of the first lens units 12 that do not have the first flat surfaces 14, thereby reducing the labor required for fixing the second sub-lenses 20b. Note that the second sub-lenses 20b shown in FIG. 19 are exemplified as a plurality of second sub-lens assemblies that are separated from each other. However, the second sub-lenses 20b may be a single second sub-lens assembly having openings on some of the first lens units.

[0061] When the first lens portion 12 of the first lens assembly 10 is provided with a hemispherical first lens portion, the second lens assembly is not disposed above the first lens portion 12. In such a case, the top surface of the hemispherical first lens portion 12 is located to the side of the second base portion 21 or second lens portion 22 of the second lens assembly. This reduces the number of optical interfaces that increases due to the placement of the second lens assembly, improving efficiency. In this case, since the light extraction efficiency varies depending on the location of the lens, the output of the light source may be adjusted as necessary to achieve a uniform brightness surface.

[0062] 19, as in the second embodiment described above, the second sub-lens 20b having one second lens portion 22 can be released from the second mold 70 by pressing a push pin against the second flat surface 24 at the corner of the second base portion 21. Another advantage is that the misalignment of the optical axes of the first lens portion 12 and the second lens portion 22 can be adjusted individually.

[0063] 19 , in a configuration in which the first flat surfaces 14 are arranged on some of the first lens portions 12, it is sufficient to ensure the position for extrusion by the first pin 66 from the first mold 60 when molding the first lens assembly 10. For example, the number of first flat surfaces 14 may be determined according to the size of the first lens assembly 10, the materials used for the first mold 60 and the first resin material, and the like, and may be one out of every ten first lens portions 12.

[0064] [Embodiment 5] Furthermore, in an example in which a second sub-lens assembly is mounted only on some of the first lens portions, the configuration is not limited to providing two types of first lens portions of the first lens assembly, one with a first flat surface and one without, and they may all be unified to one with a first flat surface 14, as in embodiment 1. Such an example is shown in Fig. 20 as a surface emitting device 500 according to embodiment 5. In this figure, the same components as those in embodiment 1 and the like are denoted by the same reference numerals (however, the sub-numbers may be different), and detailed description thereof will be omitted as appropriate.

[0065] 20 , a second lens assembly 20D includes a plurality of second sub-lenses 20d. In each second lens assembly 20D, a second lens portion 22 is not provided corresponding to all of the first lens portions 12, and a second lens portion 22 is not provided for some of the first lens portions 12. With this configuration, although the optical characteristics of the first lens portions 12 for which a second lens portion 22 is not provided are slightly reduced, the second sub-lenses 20d can be made larger and easier to mold, and the second flat surface 24 can be made wider and easier to release from the mold, and further, the number of second sub-lenses 20d can be reduced, which has the advantage of reducing manufacturing man-hours and contributing to cost reduction.

[0066] (Surface light emitting device 300) Here, details of the surface emitting device 100 including the light emitting module 30 and the lens laminate 1 will be described with reference to Figs. 21 to 25. First, the light emitting module 30 will be described. Fig. 21 is a schematic top view illustrating the light emitting module 30. The light emitting module 30 shown in Fig. 21 includes a substrate 31 and a plurality of light sources 32 arranged on the substrate 31. The plurality of light sources 32 are arranged, for example, in a matrix on the substrate 31.

[0067] Fig. 22 is a schematic top view illustrating a state in which the first lens assembly 10 is disposed in the light emitting module 30 of Fig. 21. Fig. 23 is a schematic cross-sectional view taken along line XXIII-XXIII of Fig. 22.

[0068] 2 and 22 to 23, the surface emitting device 100 includes a light emitting module 30 and a lens laminate 1 disposed above a light source 32 of the light emitting module 30. The light emitting module 30 and the lens laminate 1 are held in a housing 40 so as to have a predetermined positional relationship, for example.

[0069] 2 and 22 to 23, in the surface emitting device 100, the number of light sources 32 is equal to the number of lens regions formed by overlapping the first lens portion 12 and the second lens portion 22. In a top view, each light source 32 is positioned so as to overlap with the lens region located above the light source 32. Note that, when viewed from above, overlapping of the light source 32 with the lens region means that, when viewed from above, the light emitting surface of the light source 32 overlaps with the lens region.

[0070] In the surface emitting device 100, light emitted from the light source 32 travels vertically and diagonally upward from the light source 32 as shown in Fig. 6 and enters a lens region located above the light source 32. The light that has entered the lens region is condensed by the lens region and emitted from the first lens portion 12 to the outside of the surface emitting device 100.

[0071] Here, the components included in the light-emitting module 30 will be described in detail.

[0072] (Substrate 31) The substrate 31 is a member for mounting a plurality of light sources 32. On the upper surface of the substrate 31, conductor wiring for supplying power to the light sources 32 is arranged.

[0073] Examples of materials for the substrate 31 include ceramics, resins, composite materials, etc. Examples of resins include phenolic resin, epoxy resin, polyimide resin, BT resin, polyphthalamide (PPA), polyethylene terephthalate (PET), etc. Examples of composite materials include those obtained by mixing the above-mentioned resins with glass fiber, silicon oxide, titanium oxide, aluminum oxide, etc., and metal substrates in which a metal member is coated with an insulating layer.

[0074] A light-reflecting member 34 may be disposed on the upper surface of the substrate 31 around the light source 32. The light-reflecting member 34 is preferably made of an insulating material. The material of the light-reflecting member 34 may be, for example, at least one of a resin exemplified as the material for the substrate 31 mixed with a filler such as barium titanate, titanium oxide, aluminum oxide, silicon oxide, or zinc oxide, or a resin exemplified as the material for the substrate 31 containing a plurality of fine bubbles.

[0075] By disposing the light-reflective member 34 on the upper surface of the substrate 31, when the surface-emitting device 100 is configured with the light-emitting module 30 and the lens laminate 1, light that is emitted upward from the light source 32 and reflected downward by the lens laminate 1 is reflected upward again by the light-reflective member 34 and enters the lens laminate 1. As a result, the light extraction efficiency of the surface-emitting device 100 can be improved.

[0076] (Light source 32) 24 is a schematic cross-sectional view illustrating the light source 32 mounted on the light-emitting module 30. The light source 32 is, for example, rectangular in plan view, but may also be circular, etc. The upper surface of the light source 32 is the light-emitting surface.

[0077] 24, the light source 32 includes a base including leads 35 and a resin molded body 36, and a light emitting element 38. The base has a recess defined by a bottom surface and side surfaces. The bottom surface defining the recess is formed by a portion of the pair of leads 35 and the resin molded body 36, and the side surfaces are also formed by the resin molded body 36.

[0078] A part of the pair of leads 35 is exposed as an external terminal on the lower surface of the resin molded body 36. In the light source 32, a light emitting element 38 is placed in the recess. The light source 32 also includes a sealing member 37 that seals the light emitting element 38.

[0079] The base material constituting the lead 35 may be, for example, a plate-like body containing at least one metal selected from copper, aluminum, gold, silver, tungsten, iron, and nickel, or an alloy or clad material such as an iron-nickel alloy or phosphor bronze. A film (e.g., a plated film) containing silver, aluminum, gold, or an alloy thereof may be formed on the surface of the lead 35 in order to efficiently extract light from the light-emitting element 38. The metal film formed on the surface of the lead 35 may be a single-layer film or a multi-layer film.

[0080] The resin molded body 36 may be made of a resin containing a thermosetting resin or a thermoplastic resin. It is particularly preferable to use a thermosetting resin. The thermosetting resin is preferably a resin with lower gas permeability than the resin used for the sealing member 37. Specific examples of the thermosetting resin include epoxy resin, silicone resin, modified epoxy resin such as silicone-modified epoxy resin, modified silicone resin such as epoxy-modified silicone resin, polyimide resin, modified polyimide resin, urethane resin, and modified urethane resin. The resin molded body 36 may contain glass fiber, titanium oxide, aluminum oxide, silicon oxide, and the like.

[0081] The light emitting element 38 is placed on, for example, the bottom surface that defines the recess. The light emitting element 38 is fixed to the leads 35 by, for example, a bonding member. The light emitting element 38 has a pair of positive and negative electrodes, which are electrically connected to the pair of leads 35 via wires, respectively. Power can be supplied from an external source via the pair of leads 35 to cause the light source 32 to emit light.

[0082] The light-emitting element 38 is preferably, for example, a light-emitting diode. The light-emitting element 38 can be selected from those with any wavelength. The light-emitting element 38 emits, for example, blue, green, or red light. The light-emitting element 38 has a semiconductor stack. The semiconductor stack includes an n-type semiconductor layer, a p-type semiconductor layer, and a light-emitting layer sandwiched between them. The light-emitting layer may have a structure such as a double heterojunction or a single quantum well (SQW), or a structure with a group of active layers such as a multiple quantum well (MQW). The semiconductor stack may include multiple light-emitting layers. For example, the semiconductor stack may have a structure including two or more light-emitting layers between an n-type semiconductor layer and a p-type semiconductor layer, or may have a structure in which a structure including an n-type semiconductor layer, a light-emitting layer, and a p-type semiconductor layer in that order is repeated multiple times. When the semiconductor stack includes multiple light-emitting layers, the emission peak wavelengths may differ among the multiple light-emitting layers, or the semiconductor stack may include light-emitting layers with the same emission peak wavelength. The light-emitting element 38 can be made of a nitride-based semiconductor such as GaN, InGaN, AlGaN, or AlInGaN. Furthermore, the red light-emitting element can be made of GaAlAs, AlInGaP, or the like. Furthermore, semiconductor light-emitting elements made of other materials may also be used. The composition, light-emitting color, size, number, and other factors of the light-emitting elements used can be appropriately selected depending on the purpose.

[0083] The light-emitting element 38 is covered with a light-transmitting sealing member 37. A resin having excellent heat resistance, weather resistance, and light resistance is preferably used as the sealing member 37. Examples of such resins include silicone resin, modified silicone resin, epoxy resin, modified epoxy resin, urea resin, phenol resin, acrylic resin, urethane resin, or fluororesin, or a resin containing two or more of these resins.

[0084] To provide a desired function, the sealing member 37 can be mixed with at least one selected from the group consisting of fillers, pigments, and phosphors. Suitable fillers include barium titanate, titanium oxide, aluminum oxide, silicon oxide, and zinc oxide. The sealing member 37 may also contain organic or inorganic coloring dyes or coloring pigments to transmit light in a desired wavelength range. Furthermore, the sealing member 37 may also contain a phosphor.

[0085] When the sealing member 37 contains a phosphor, it functions as a wavelength conversion member. The wavelength conversion member absorbs at least a portion of the light emitted from the light emitting element 38 and emits light of a wavelength different from the wavelength of the light from the light emitting element 38. For example, the wavelength conversion member converts the wavelength of a portion of the blue light from the light emitting element 38 to emit yellow light. With this configuration, white light is obtained by mixing the blue light that has passed through the wavelength conversion member with the yellow light emitted from the wavelength conversion member.

[0086] Furthermore, the light source 32 may optionally include other elements such as a protective element, electronic components, etc. These elements and electronic components are preferably embedded in the resin molded body.

[0087] The light source 32 may be a light emitting element 38 only, instead of the light emitting device shown in FIG.

[0088] [Embodiment 6] The surface emitting device may include a reflector. Such an example is shown in Fig. 25 as a surface emitting device 600 according to embodiment 6. In this figure, the same components as those in embodiment 1 and the like are denoted by the same reference numerals (however, the sub-numbers may be different), and detailed description thereof will be omitted as appropriate.

[0089] 25, a reflector 80 is disposed between each of the plurality of light sources 32. By disposing the reflectors 80 in this manner, the light emitted from the light sources 32 can be made to efficiently enter the first lens.

[0090] Fig. 25 is a schematic partial cross-sectional view illustrating a surface emitting device 600 including a light emitting module 30E and a lens laminate 1. As shown in Fig. 25, the surface emitting device 600 may include a light emitting module 30E instead of the light emitting module 30. The light emitting module 30E differs from the light emitting module 30 in that it includes a reflector 80.

[0091] The reflector 80 is disposed on the same side of the substrate 31 as the light sources 32. The reflector 80 includes top portions 81 arranged in a lattice pattern in a top view, wall portions 82 surrounding each of the light sources 32 in a top view, and a bottom portion 83 connected to the lower ends of the wall portions 82, and has a plurality of regions surrounding the light sources 32. The wall portions 82 of the reflector 80 extend, for example, from the top portion 81 toward the substrate 31, and in a cross-sectional view, the width of the region surrounded by the opposing wall portions 82 becomes narrower as it approaches the substrate 31. One light source 32 is disposed in one section surrounded by the wall portions 82. However, two or more light sources 32 may be disposed in one section. The reflector 80 may be separated from the lens stack 1, or the top portion 81 of the reflector 80 may be in contact with the lens stack 1.

[0092] The reflector 80 has light reflectivity. This allows the light emitted from the light source 32 to be efficiently reflected toward the lens laminate 1 by the reflector 80. In this case, the reflector 80 may be molded using a resin containing a reflective material such as titanium oxide, aluminum oxide, or silicon oxide, or may be molded using a resin that does not contain a reflective material and then a reflective material is disposed on the surface. Alternatively, the reflector 80 may be made of a resin containing a plurality of fine bubbles. In this case, light is reflected at the interface between the bubbles and the resin. Examples of resins used for the reflector 80 include thermoplastic resins such as acrylic resin, polycarbonate resin, cyclic polyolefin resin, polyethylene terephthalate, polyethylene naphthalate, and polyester, and thermosetting resins such as epoxy resin and silicone resin. The reflector 80 is preferably set to have a reflectance of 70% or more for the light emitted from the light source 32.

[0093] In the above example, the light emitting module 30 used in the surface emitting device 100 is described as having the substrate 31, but the substrate is arranged as needed and can be omitted. For example, in a surface emitting device, a light emitting module in which multiple light emitting elements are held together by a light-transmitting resin or the like can be used.

[0094] [Example] Here, in order to demonstrate the usefulness of the surface emitting device according to the present disclosure, simulations were performed on the surface emitting device according to Example 1 and the surface emitting devices according to Comparative Examples 1 to 4. In the surface emitting device according to Example 1, a lens stack 1 having a second lens assembly 20 superimposed on the upper surface of a first lens assembly 10 was placed above a light emitting module 30, as shown in FIG.

[0095] As shown in FIG. 26, a surface-emitting device 2600 according to Comparative Example 1 includes only a light-emitting module 2630 and does not include a lens. On the other hand, as shown in FIG. 27, a surface-emitting device 2700 according to Comparative Example 2 includes a single lens disposed above a light-emitting module 2730. As shown in FIG. 28, a surface-emitting device 2800 according to Comparative Example 3 includes only a first lens assembly 2810, and as shown in FIG. 29, a surface-emitting device 2900 according to Comparative Example 4 includes only a second lens assembly 2920, both of which are combined with light-emitting modules 2830 and 2930. Simulation results for determining the luminance distributions of the surface-emitting devices according to Example 1 and Comparative Examples 1 to 4 are shown in FIGS. 30 to 34. These results confirm that the surface-emitting devices according to Comparative Examples 1 to 4 each exhibit luminance unevenness, whereas the surface-emitting device 100 according to Example 1 exhibits reduced luminance unevenness.

[0096] Although the preferred embodiments have been described in detail above, the present invention is not limited to the above-described embodiments, and various modifications and substitutions can be made to the above-described embodiments without departing from the scope of the claims.

[0097] The present disclosure can also be implemented in the following manner.

[0098] [Section 1] Multiple light sources; a lens stack disposed above the plurality of light sources; A surface emitting device comprising: The lens laminate is a first base portion facing the plurality of light sources on a lower surface thereof; a plurality of first lens portions located on the first base and having first central axes that coincide with the optical axes of the plurality of light sources; a first lens assembly having a second base portion facing the first lens assembly at a lower surface thereof; a plurality of second lens portions located on the second base and having second central axes that coincide with the first central axes of the plurality of first lens portions; a second lens assembly having Equipped with the plurality of first lens portions have circular outer peripheries in a top view, and top surfaces are first flat surfaces, and the first lens portions are arranged such that the outer peripheries of adjacent first lens portions are in contact with each other; A surface emitting device, wherein the second lens portion has a circular outer periphery when viewed from above, and adjacent second lens portions are arranged so as to be spaced apart via a connecting surface which is a second flat surface.

[0099] [Section 2] Item 2. The surface emitting device according to item 1, wherein a first diameter of the top surface of the first lens portion is equal to or smaller than a second diameter of the second lens portion.

[0100] [Section 3] 3. The surface emitting device according to item 1 or 2, wherein the first radius of curvature of the first lens portion and the second radius of curvature of the second lens portion are the same.

[0101] [Section 4] 4. The surface emitting device according to any one of items 1 to 3, wherein the thickness of the first lens portion is greater than the thickness of the second lens portion.

[0102] [Section 5] 5. The surface emitting device according to any one of items 1 to 4, wherein the light source includes a light emitting element and a wavelength conversion member disposed on the light emitting element.

[0103] [Section 6] 6. The surface emitting device according to any one of items 1 to 5, wherein the width of the light source in a cross section including the optical axis of the light source is 15% to 50% of the maximum width of the first lens portion.

[0104] [Section 7] 7. The surface emitting device according to any one of items 1 to 6, wherein the thickness of the first base portion is thinner than the thickness of the first lens portion.

[0105] [Section 8] 8. The surface emitting device according to any one of items 1 to 7, wherein the second lens assembly is composed of a plurality of second sub-lens assemblies each including one or more of the second lens portions.

[0106] [Section 9] Item 9. The surface emitting device according to any one of items 1 to 8, further comprising reflectors arranged between the plurality of light sources.

[0107] [Section 10] 1. A lens stack for placement over a plurality of light sources, comprising: a first base portion for facing the plurality of light sources from a lower surface thereof; a plurality of first lens portions positioned on the first base and having first central axes for aligning with the optical axes of the plurality of light sources; a first lens assembly having a second base portion for facing the first lens assembly from below; a plurality of second lens portions located on the second base and having second central axes that are aligned with the first central axes of the plurality of first lens portions; a second lens assembly having Equipped with the plurality of first lens portions have circular outer peripheries in a top view, and top surfaces are first flat surfaces, and the first lens portions are arranged such that the outer peripheries of adjacent first lens portions are in contact with each other; A lens stack, wherein the second lens portions have a circular outer periphery when viewed from above, and adjacent second lens portions are arranged so as to be spaced apart via a connecting surface that is a second flat surface.

[0108] [Section 11] a first mold having a plurality of first recesses each having a circular outer periphery in a top view and a first flat portion as a bottom surface, the first recesses being arranged such that the outer peripheries of adjacent first recesses are in contact with each other; a mold preparation step of preparing a second mold including second recesses each having a circular outer periphery in a top view, the outer peripheries of adjacent second recesses being spaced apart from each other, and a second flat portion surrounding the outer peripheries of the second recesses; a step of molding a first lens assembly using the first mold, the first lens assembly including a first base and a plurality of first lens portions positioned on the first base; a step of releasing the first lens assembly from the first mold by bringing a first pin into contact with a top surface of the first lens portion molded in the first recess, the top surface being molded in the first flat portion of the first recess; a step of molding a second lens assembly using the second mold, the second lens assembly including a second base and a plurality of second lens portions disposed on the second base; a step of releasing the second lens assembly from the second mold by bringing a second pin into contact with a connection surface formed by molding the second flat portion of the second recess; a step of placing the second lens assembly released from the second mold on the first lens assembly released from the first mold; A method for manufacturing a lens laminate, comprising:

[0109] [Section 12] Item 12. The method for manufacturing a lens laminate according to Item 11, wherein the diameter of the first flat portion of the first recess of the first mold is larger than the depth of the first recess.

[0110] [Section 13] Item 13. The method for manufacturing a lens laminate according to Item 11 or 12, wherein a diameter of the first flat surface portion of the first recessed portion of the first mold is equal to or smaller than a diameter of an opening of the second recessed portion of the second mold.

[0111] [Section 14] A step of preparing a lens laminate by the method according to any one of items 11 to 13; Providing a plurality of light sources; a step of disposing the lens stack on the light source so that a first central axis of the first lens portion and a second central axis of the second lens portion coincide on an optical axis of the light source; A method for manufacturing a surface emitting device, comprising:

[0112] [Section 15] a first mold preparation step of preparing a first mold having a plurality of first recesses, each having a circular outer periphery in a top view and a first flat portion as a bottom surface, the first recesses being arranged such that the outer peripheries of adjacent first recesses are in contact with each other; a step of molding a first lens assembly using the first mold, the first lens assembly including a first base and a plurality of first lens portions positioned on the first base; a step of releasing the first lens assembly from the first mold by bringing a first pin into contact with a top surface of the first lens portion molded in the first recess, the top surface being molded in the first flat portion of the first recess; A method for manufacturing a first lens assembly, comprising:

[0113] [Section 16] a second mold preparation step of preparing a second mold including second recesses each having a circular outer periphery in a top view, the outer peripheries of adjacent second recesses being spaced apart from each other, and a second flat portion surrounding the outer peripheries of the second recesses; a step of molding a second lens assembly using the second mold, the second lens assembly including a second base and a plurality of second lens portions disposed on the second base; a step of releasing the second lens assembly from the second mold by bringing a second pin into contact with a connection surface formed by molding the second flat portion of the second recess; A method for manufacturing a second lens assembly, comprising: [Industrial Applicability]

[0114] The surface-emitting device, lens laminate and manufacturing method thereof, manufacturing method for a surface-emitting device, manufacturing method for a first lens assembly, and manufacturing method for a second lens assembly according to the present disclosure can be suitably used for backlights and surface-emitting devices for liquid crystal displays that use semiconductor light-emitting elements such as LEDs and LDs, surface-emitting devices, in-vehicle light sources, etc. For example, they can be suitably used for displays, smartphones, tablets, in-vehicle monitors, screens such as the screens of HMDs and smart glasses, etc. [Explanation of symbols]

[0115] 100, 200, 300, 400, 500, 600... Surface emitting device 1...Lens laminate 10...First lens assembly 11...First base 12...First lens section 13...First central axis 14...First flat surface 20, 20B, 20C, 20D...Second lens assembly 20b, 20c, 20d...Second sub-lens 21...Second base 22...Second lens part 23…Second central axis 24…Second flat surface 30, 30E...light-emitting module 31... Circuit board 32…Light source 33...Optical axis 34...Light-reflective member 35…Lead 36...Resin molding 37...Sealing member 38...Light emitting element 40…Case 41...Base 42...Wall part 43…Second top surface 60...First mold 61...First upper mold 62...First lower mold 63...First recess 64...First plane part 65...First cavity 66...First pin 67...First upper die step 70...Second mold 71...Second upper mold 72...Second lower mold 73...Second recess 74…Second plane part 75...Second cavity 76...Second pin 77...Second upper die step 80...Reflector 81...Top 82…Wall part 83…Bottom 800, 2600, 2700, 2800, 2900... Surface emitting device 2630, 2730, 2830, 2930...light-emitting modules 810, 2810...First lens assembly 820, 2920...Second lens assembly DL1: First diameter of the first flat surface of the first lens part DL2: Second diameter of second lens part TL1: Thickness of the first lens TL2: Thickness of the second lens TB1: Thickness of the first base PL: Diameter of the first lens PS: Light source width

Claims

1. Multiple light sources; a lens stack disposed above the plurality of light sources; A surface emitting device comprising: The lens laminate is a first base portion facing the plurality of light sources on a lower surface thereof; a plurality of first lens portions located on the first base and having first central axes that coincide with the optical axes of the plurality of light sources; a first lens assembly having a second base portion facing the first lens assembly at a lower surface thereof; a plurality of second lens portions located on the second base and having second central axes that coincide with the first central axes of the plurality of first lens portions; a second lens assembly having Equipped with the plurality of first lens portions have circular outer peripheries in a top view, and top surfaces are first flat surfaces, and the first lens portions are arranged such that the outer peripheries of adjacent first lens portions are in contact with each other; A surface emitting device, wherein the second lens portion has a circular outer periphery when viewed from above, and adjacent second lens portions are arranged so as to be spaced apart via a connecting surface which is a second flat surface.

2. The surface emitting device according to claim 1 , wherein a first diameter of the top surface of the first lens portion is equal to or smaller than a second diameter of the second lens portion.

3. The surface emitting device according to claim 1 , wherein the first radius of curvature of the first lens portion and the second radius of curvature of the second lens portion are the same.

4. The surface emitting device according to claim 1 , wherein the thickness of the first lens portion is greater than the thickness of the second lens portion.

5. The surface emitting device according to claim 1 , wherein the light source comprises a light emitting element and a wavelength converting member disposed on the light emitting element.

6. The surface emitting device according to claim 1 , wherein the width of the light source in a cross section including an optical axis of the light source is 15% to 50% of the maximum width of the first lens portion.

7. The surface emitting device according to claim 1 , wherein the thickness of the first base portion is thinner than the thickness of the first lens portion.

8. The surface emitting device according to claim 1 , wherein the second lens assembly is composed of a plurality of second sub-lens assemblies each including one or more of the second lens portions.

9. 9. The surface emitting device according to claim 1, further comprising a reflector disposed between the plurality of light sources.

10. 1. A lens stack for placement over a plurality of light sources, comprising: a first base portion for facing the plurality of light sources from a lower surface thereof; a plurality of first lens portions positioned on the first base and having first central axes for aligning with the optical axes of the plurality of light sources; a first lens assembly having a second base portion for facing the first lens assembly from below; a plurality of second lens portions located on the second base and having second central axes that are aligned with the first central axes of the plurality of first lens portions; a second lens assembly having Equipped with the plurality of first lens portions have circular outer peripheries in a top view, and top surfaces are first flat surfaces, and the first lens portions are arranged such that the outer peripheries of adjacent first lens portions are in contact with each other; A lens stack, wherein the second lens portions have a circular outer periphery when viewed from above, and adjacent second lens portions are arranged so as to be spaced apart via a connecting surface that is a second flat surface.

11. a first mold having a plurality of first recesses each having a circular outer periphery in a top view and a first flat portion as a bottom surface, the first recesses being arranged such that the outer peripheries of adjacent first recesses are in contact with each other; a mold preparation step of preparing a second mold including second recesses each having a circular outer periphery in a top view, the outer peripheries of adjacent second recesses being spaced apart from each other, and a second flat portion surrounding the outer peripheries of the second recesses; a step of molding a first lens assembly using the first mold, the first lens assembly including a first base and a plurality of first lens portions positioned on the first base; a step of releasing the first lens assembly from the first mold by bringing a first pin into contact with a top surface of the first lens portion molded in the first recess, the top surface being molded in the first flat portion of the first recess; a step of molding a second lens assembly using the second mold, the second lens assembly including a second base and a plurality of second lens portions disposed on the second base; a step of releasing the second lens assembly from the second mold by bringing a second pin into contact with a connection surface formed by molding the second flat portion of the second recess; a step of placing the second lens assembly released from the second mold on the first lens assembly released from the first mold; A method for manufacturing a lens laminate, comprising:

12. The method for manufacturing a lens laminate according to claim 11 , wherein a diameter of the first flat portion of the first recess of the first mold is larger than a depth of the first recess.

13. The method for manufacturing a lens laminate according to claim 11 , wherein a diameter of the first flat surface portion of the first recessed portion of the first mold is the same as or smaller than a diameter of an opening of the second recessed portion of the second mold.

14. Providing a lens stack by the method of any one of claims 11 to 13; Providing a plurality of light sources; a step of disposing the lens stack on the light source so that a first central axis of the first lens portion and a second central axis of the second lens portion coincide on an optical axis of the light source; A method for manufacturing a surface emitting device, comprising:

15. a first mold preparation step of preparing a first mold having a plurality of first recesses, each having a circular outer periphery in a top view and a first flat portion as a bottom surface, the first recesses being arranged such that the outer peripheries of adjacent first recesses are in contact with each other; a step of molding a first lens assembly using the first mold, the first lens assembly including a first base and a plurality of first lens portions positioned on the first base; a step of releasing the first lens assembly from the first mold by bringing a first pin into contact with a top surface of the first lens portion molded in the first recess, the top surface being molded in the first flat portion of the first recess; A method for manufacturing a lens assembly, comprising:

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