Light Emitting Module

Abstract

To provide a light-emitting module which can be made thin.SOLUTION: A light-emitting module comprises: a light guide member which has a first surface and a second surface opposite to the first surface and includes a first region including a recess opening to the second surface, a second region surrounding the first region in plan view, a third region surrounding the second region in plan view; and a light source placed in the recess. The first surface includes a concave surface arranged over the first region and the second region in such a manner that the deepest portion is located in the first region. The second surface includes a convex surface protruding from a third region along the concave surface in the second region.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a light emitting module. [Background technology]

[0002] Light-emitting modules that combine light-emitting elements such as light-emitting diodes with light guide plates are widely used in planar light sources such as backlights for liquid crystal displays. For example, Patent Document 1 discloses a planar light source in which LEDs mounted on a flexible printed circuit board are placed in recesses in a light guide plate, and a reflective sheet having holes through which the LEDs pass is provided on the lower surface of the light guide plate. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2010-8837 A Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present invention is to provide a light-emitting module that can be made thin. [Means for solving the problem]

[0005] According to one aspect of the present invention, a light emitting module includes a light guide member having a first surface and a second surface opposite to the first surface, the light guide member having a first region including a recess opening to the second surface, a second region surrounding the first region in a plan view, and a third region surrounding the second region in a plan view, and a light source disposed in the recess. The first surface includes a concave surface disposed across the first region and the second region such that a deepest part is located in the first region. The second surface includes a convex surface in the second region that protrudes from the third region and follows the concave surface. Effect of the Invention

[0006] According to the present invention, it is possible to provide a light-emitting module that can be made thin. [Brief description of the drawings]

[0007] [Figure 1A] 1 is a perspective view of a first surface side of a light-emitting module according to an embodiment of the present invention. [Figure 1B] 2 is a perspective view of a second surface side of the light-emitting module according to one embodiment of the present invention. FIG. [Diagram 2] FIG. 1B is a cross-sectional view taken along line II-II in FIG. 1A. [Figure 3A] 2 is a top view of a light source in the light emitting module of one embodiment of the present invention. FIG. [Figure 3B] 2 is a bottom view of a light source in the light emitting module of the embodiment of the present invention. FIG. [Figure 3C] FIG. 3B is a cross-sectional view taken along line IIIC-IIIC in FIG. 3A. [Figure 3D] 4 is a cross-sectional view showing another example of a light source in the light-emitting module of one embodiment of the present invention. FIG. [Figure 4] 1 is a cross-sectional perspective view showing a method for manufacturing a light-emitting module according to an embodiment of the present invention; [Diagram 5] 1 is a cross-sectional perspective view showing a method for manufacturing a light-emitting module according to an embodiment of the present invention; [Figure 6] 1 is a cross-sectional perspective view showing a method for manufacturing a light-emitting module according to an embodiment of the present invention; [Figure 7] 1 is a cross-sectional perspective view showing a method for manufacturing a light-emitting module according to an embodiment of the present invention; [Figure 8] 1 is a cross-sectional perspective view showing a method for manufacturing a light-emitting module according to an embodiment of the present invention; [Figure 9] 1 is a cross-sectional perspective view showing a method for manufacturing a light-emitting module according to an embodiment of the present invention; [Figure 10] 1 is a cross-sectional perspective view showing a method for manufacturing a light-emitting module according to an embodiment of the present invention; [Figure 11] 1 is a perspective view showing a manufacturing method of a light-emitting module according to an embodiment of the present invention; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, the embodiments will be described with reference to the drawings. Since each drawing is a schematic representation of the embodiment, the size, spacing, or positional relationship of each member may be exaggerated, some members may be omitted, or an end view showing only a cut surface may be used as a cross-sectional view. In each drawing, the same components are denoted by the same reference numerals. In addition, in this disclosure, "planar view" refers to a view from the first surface side or the second surface side of the light-guiding member.

[0009] Fig. 1A is a perspective view of a first surface 11 side of a light-emitting module 1 according to one embodiment of the present invention. Fig. 1B is a perspective view of a second surface 12 side of the light-emitting module 1. Fig. 2 is a cross-sectional view taken along line II-II in Fig. 1A.

[0010] The light emitting module 1 includes at least a light guide member 10 , a light source 20 , a first light reflective member 41 , a second light reflective member 42 , a third light reflective member 43 , a light adjustment member 44 , and a first light transmissive member 31 .

[0011] Light from the light source 20 is guided to the light-guiding member 10. The light-guiding member 10 is translucent to the light from the light source 20. The transmittance of the light-guiding member 10 to the light from the light source 20 is, for example, preferably 80% or more, and more preferably 90% or more. The light source 20 has at least a light-emitting element 22. The light from the light source 20 includes light emitted by the light-emitting element 22. In addition, when the light source 20 includes a phosphor, the light from the light source 20 also includes light emitted by the phosphor.

[0012] The light guide member 10 may be made of a material such as a thermoplastic resin, such as acrylic, polycarbonate, cyclic polyolefin, polyethylene terephthalate, or polyester, a thermosetting resin, such as epoxy or silicone, or glass.

[0013] The light guide member 10 has a first surface 11 which is the light emitting surface of the light emitting module 1, and a second surface 12 opposite to the first surface 11. The thickness of the light guide member 10 is preferably such that the shortest distance between the first surface 11 and the second surface 12 is, for example, 50 μm to 250 μm in the first region a1, 100 μm to 700 μm in the second region a2, and 200 μm to 800 μm in the third region a3. The light guide member 10 may be composed of a single layer in the thickness direction, or may be composed of a laminate of multiple layers. When the light guide member 10 is composed of a laminate, a light-transmitting adhesive member can be disposed between each layer. The layers of the laminate can be made of the same or different materials, for example, from the materials of the light guide member 10 described above. The adhesive member can be made of, for example, a thermoplastic resin such as acrylic, polycarbonate, cyclic polyolefin, polyethylene terephthalate, or polyester, or a thermosetting resin such as epoxy or silicone.

[0014] The light guide member 10 has a first region a1, a second region a2 surrounding the first region a1 in a planar view, and a third region a3 surrounding the second region a2 in a planar view. In Fig. 1A, the boundaries between the first region a1 and the second region a2 and the boundaries between the second region a2 and the third region a3 are indicated by dashed lines.

[0015] The first region a1 includes a recess 13 (hereinafter, referred to as a first recess) that opens to the second surface 12. The first surface 11 includes a concave surface 11a that is disposed across the first region a1 and the second region a2 so that the deepest part is located in the first region a1. The second surface 12 includes a convex surface 12a in the second region a2 that protrudes more than the third region a3 so as to be along the concave surface 11a of the first surface 11. The direction that connects the concave surface 11a and the convex surface 12a in the second region a2 at the shortest distance is inclined with respect to the direction that connects the first surface 11 and the second surface 12 at the third region a3 at the shortest distance. Note that "along the concave surface 11a" means that it is parallel or approximately parallel to the concave surface 11a. Furthermore, "approximately parallel to the concave surface 11a" means that an inclination of within ±3° with respect to the concave surface 11a is permitted.

[0016] The first surface 11 and the second surface 12 in the third region a3 are parallel or approximately parallel. Note that the first surface 11 and the second surface 12 being approximately parallel means that either one of the first surface 11 and the second surface 12 is allowed to have an inclination of ±3° or less with respect to the other surface.

[0017] The light source 20 is disposed in the first recess 13 of the light guide member 10 via a first light-transmissive member 31. Fig. 3A is a top view of the light source 20. Fig. 3B is a bottom view of the light source 20. Fig. 3C is a cross-sectional view taken along line IIIC-IIIC in Fig. 3A.

[0018] The light source 20 may be a single light-emitting element 22, or may have a structure in which the light-emitting element 22 is combined with a second light-transmissive member 24 as shown in Fig. 3C. The light source 20 may further include a light-reflective covering member 25. The second light-transmissive member 24 and the covering member 25 will be described in detail later.

[0019] The light emitting element 22 includes a semiconductor laminate and a pair of positive and negative electrodes electrically connected to the semiconductor laminate. The semiconductor laminate includes, for example, a support substrate such as sapphire or gallium nitride, an n-type semiconductor layer and a p-type semiconductor layer disposed on the support substrate, and a light emitting layer sandwiched between the n-type semiconductor layer and the p-type semiconductor layer. The pair of positive and negative electrodes includes an n-side electrode and a p-side electrode electrically connected to the n-type semiconductor layer and the p-type semiconductor layer, respectively. The semiconductor laminate may be one from which the support substrate has been removed. The structure of the light emitting layer may be a structure having a single active layer such as a double heterostructure or a single quantum well structure (SQW), or a structure having a group of active layers such as a multiple quantum well structure (MQW). The light emitting layer can emit visible light or ultraviolet light. The light emitting layer can emit visible light ranging from blue to red. Examples of semiconductor laminates including such a light emitting layer include In x Al y Ga 1-x-y N (0≦x, 0≦y, x+y≦1).

[0020] The semiconductor laminate may include at least one light-emitting layer capable of emitting the above-mentioned light. For example, the semiconductor laminate may have a structure including one 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 sequence is repeated multiple times. When the semiconductor laminate includes multiple light-emitting layers, the semiconductor laminate may include light-emitting layers having different emission peak wavelengths, or may include light-emitting layers having the same emission peak wavelength. The same emission peak wavelength may have a variation of about several nm in the emission peak wavelength, for example. Such a combination of emission peak wavelengths can be appropriately selected. For example, when the semiconductor laminate includes two light-emitting layers, the light-emitting layers can be selected from combinations such as blue light and blue light, green light and green light, red light and red light, ultraviolet light and ultraviolet light, blue light and green light, blue light and red light, or green light and red light. The light-emitting layer may include multiple active layers having different emission peak wavelengths, or may include multiple active layers having the same emission peak wavelength.

[0021] 3C, the second light-transmissive member 24 covers the upper surface and side surfaces of the light-emitting element 22. The second light-transmissive member 24 is translucent to the light from the light source 20, and may be made of a light-transmissive resin such as silicone or epoxy. The second light-transmissive member 24 protects the light-emitting element 22 and can have functions such as wavelength conversion and light diffusion depending on particles added to the second light-transmissive member 24.

[0022] The second light-transmitting member 24 may further include a wavelength conversion material, such as a phosphor, that converts the light from the light-emitting element 22 into light with a different peak wavelength. The phosphor may be an yttrium-aluminum-garnet phosphor (e.g., Y3(Al,Ga)5O 12 :Ce), lutetium aluminum garnet phosphors (e.g., Lu3(Al,Ga)5O 12 :Ce), terbium aluminum garnet phosphors (e.g., Tb3(Al,Ga)5O 12 :Ce), CCA phosphors (e.g., Ca 10(PO4)6Cl2:Eu), SAE phosphors (e.g., Sr4Al 14 O 25 :Eu), chlorosilicate phosphors (e.g., Ca8MgSi4O 16 Cl2:Eu), β-sialon phosphors (e.g., (Si,Al)3(O,N)4:Eu), α-sialon phosphors (e.g., Ca(Si,Al) 12 (O,N) 16 :Eu), SLA phosphor (e.g., SrLiAl3N4:Eu), CASN phosphor (e.g., CaAlSiN3:Eu) or SCASN phosphor (e.g., (Sr,Ca)AlSiN3:Eu), or other nitride phosphor; KSF phosphor (e.g., K2SiF6:Mn), KSAF phosphor (e.g., K2(Si,Al)F6:Mn) or other fluoride phosphor; phosphor having a perovskite structure (e.g., CsPb(F,Cl,Br,I)3), or quantum dot phosphor (e.g., CdSe, InP, AgInS2, or AgInSe2), or the like, may be used as the phosphor added to the second light-transmitting member 24. One type of phosphor or multiple types of phosphors may be used as the phosphor added to the second light-transmitting member 24.

[0023] The KSAF phosphor may have a composition represented by the following formula (I). M2[Si p Al q Mn r F s ] (I)

[0024] In formula (I), M represents an alkali metal and may contain at least K. Mn may be a tetravalent Mn ion. p, q, r, and s may satisfy 0.9 ≦ p + q + r ≦ 1.1, 0 < q ≦ 0.1, 0 < r ≦ 0.2, 5.9 ≦ s ≦ 6.1. Preferably, 0.95 ≦ p + q + r ≦ 1.05 or 0.97 ≦ p + q + r ≦ 1.03, 0 < q ≦ 0.03, 0.002 ≦ q ≦ 0.02 or 0.003 ≦ q ≦ 0.015, 0.005 ≦ r ≦ 0.15, 0.01 ≦ r ≦ 0.12 or 0.015 ≦ r ≦ 0.1, 5.92 ≦ s ≦ 6.05 or 5.95 ≦ s ≦ 6.025. For example, compositions represented by K2[Si 0.946 Al 0.005 Mn 0.049 F 5.995 , K2[Si 0.942 Al 0.008 Mn 0.050 F 5.992 , K2[Si 0.939 Al 0.014 Mn 0.047 F 5.986 can be mentioned. According to such a KSAF-based phosphor, high luminance and red light emission with a narrow full width at half maximum of the emission peak wavelength can be obtained.

[0025] On the lower surface side of the light-emitting element 22, electrodes 23 electrically connected to the n-type semiconductor layer and the p-type semiconductor layer of the light-emitting element 22 are disposed. The covering member 25 is disposed at least on the lower surface side of the light-emitting element 22. The covering member 25 is disposed such that at least a part of the surface (the lower surface in FIG. 3C) of the electrode 23 is exposed from the covering member 25. The covering member 25 covers the lower surface of the second light-transmissive member 24 and the side surface of the electrode 23.

[0026] The covering member 25 is reflective to the light from the light source 20. The covering member 25 is, for example, a resin member containing a light diffusing agent. Examples of the light diffusing agent include particles of SiO2, CaF2, MgF2, TiO2, Nb2O5, BaTiO3, Ta2O5, Zr2O3, ZnO, Y2O3, Al2O3, MgO, or BaSO4. Examples of the resin base material include silicone resin, epoxy resin, or acrylic resin. The covering member 25 may also be, for example, ceramics, preferably fine ceramics.

[0027] The light source 20 may also include a light reflective member that covers the entire or part of the upper surface of the second light-transmitting member 24. The light reflective member is a resin member that has reflectivity and translucency with respect to the light from the light-emitting element 22 and contains, for example, a light diffusing agent or air bubbles. The light reflective member may also be, for example, a metal member such as Al or Ag, a DBR (Distributed Bragg Reflector), or ceramics (preferably fine ceramics). Such a light reflective member can diffuse and reflect a part of the light emitted from the upper surface of the second light-transmitting member 24, thereby reducing uneven brightness in the light-emitting surface of the light-emitting module 1.

[0028] 3D is a cross-sectional view showing another example of the light source. In this light source, a covering member 25 covers the side and bottom surfaces of the light emitting element 22. A second light-transmissive member 24 covers the top surface of the light emitting element 22 and the top surface of the covering member 25. The covering member 25 is disposed so that at least a part of the surface (bottom surface in FIG. 3D) of the electrode 23 disposed on the bottom surface of the light emitting element 22 is exposed. In this case, the covering member 25 covers the side surfaces of the electrode 23.

[0029] 2, a first light-transmissive member 31 is disposed in the first recess 13 of the light-guiding member 10. The first light-transmissive member 31 is transmissive to light from the light source 20, and is made of a light-transmissive resin such as silicone or epoxy. The first light-transmissive member 31 may also contain a phosphor.

[0030] The first light-transmissive member 31 covers the top and side surfaces of the light source 20. The first light-transmissive member 31 also covers the inner surface (side surface and bottom surface) of the first recess 13. As in the example shown in FIG. 2, the first light-transmissive member 31 may be disposed only within the first recess 13, or a part of the first light-transmissive member 31 may extend so as to further cover the convex surface 12a of the second surface 12 located around the first recess 13. The light source 20 is fixed to the light-guiding member 10 by the first light-transmissive member 31.

[0031] A light adjusting member 44 is disposed on the concave surface 11a of the first surface 11 of the light guide member 10. The light adjusting member 44 is disposed above the light source 20. The light adjusting member 44 is disposed across the first region a1 and the second region a2.

[0032] The light adjustment member 44 is reflective and translucent to the light from the light source 20. The light adjustment member 44 may include a translucent resin and a light diffusing agent or air bubbles dispersed in the translucent resin. The translucent resin may be, for example, a silicone resin or an epoxy resin. The light diffusing agent may be, for example, particles of SiO2, CaF2, MgF2, TiO2, Nb2O5, BaTiO3, Ta2O5, Zr2O3, ZnO, Y2O3, Al2O3, MgO, or BaSO4. The light adjustment member 44 may be, for example, a metal member such as Al or Ag, a distributed Bragg reflector (DBR), or ceramics (preferably fine ceramics).

[0033] Such a light adjustment member 44 diffusely reflects a part of the light emitted upward from the light source 20 and transmits the other part. This makes it possible to prevent the brightness of the area directly above the light source 20 from becoming extremely higher than the brightness of other areas, and to reduce brightness unevenness in the light-emitting surface of the light-emitting module 1.

[0034] A first light reflective member 41 is disposed on the convex surface 12a of the second surface 12 of the light guide member 10. The first light reflective member 41 is a resin member containing a light diffusing agent. Examples of the resin include silicone and epoxy. Examples of the light diffusing agent include particles of SiO2, CaF2, MgF2, TiO2, Nb2O5, BaTiO3, Ta2O5, Zr2O3, ZnO, Y2O3, Al2O3, MgO, or BaSO4.

[0035] The first light reflective member 41 is also disposed at a position overlapping the first recess 13 in a plan view. In detail, the first light reflective member 41 covers the lower surface of the first light transmissive member 31 disposed in the first recess 13. A part of the light source 20 (for example, a portion including the electrode 23 and the covering member 25) is disposed outside the first recess 13, and the first light reflective member 41 covers the side surface of the part of the light source 20.

[0036] The light reflective member 40 is adhered to the third region a3 of the second surface 12, for example, via a light-transmitting adhesive sheet. The adhesive sheet may contain a light diffusing agent. The light reflective member 40 includes a second light reflective member 42 and a third light reflective member 43. The second light reflective member 42 and the third light reflective member 43 are also adhered to each other, for example, via an adhesive sheet.

[0037] Light reflective member 40 includes a laminated portion of second light reflective member 42 and third light reflective member 43, and a single layer portion of third light reflective member 43. In the laminated portion, second light reflective member 42 is located between second surface 12 and third light reflective member 43. In addition, in the laminated portion, second light reflective member 42 and third light reflective member 43 surround first light reflective member 41 in a plan view. The single layer portion of third light reflective member 43 surrounds second light reflective member 42 in a plan view.

[0038] The third light reflective member 43 extends from the single layer portion so as to cover the second light reflective member 42, and is in contact with the first light reflective member 41. The second light reflective member 42 is also in contact with the first light reflective member 41. In other words, there is no gap between the second light reflective member 42 and the first light reflective member 41, and there is also no gap between the third light reflective member 43 covering the second light reflective member 42 and the first light reflective member 41.

[0039] The second light reflective member 42 is, for example, a member in which a plurality of insulating films with different refractive indices are laminated. For example, a polyester resin can be used as this insulating film. The third light reflective member 43 is, for example, a resin member containing a plurality of bubbles. For example, polyethylene terephthalate can be used as the base resin.

[0040] The diffuse reflectance of the second light reflective member 42 is lower than the diffuse reflectance of the first light reflective member 41. The diffuse reflectance of the third light reflective member 43 is lower than the diffuse reflectance of the first light reflective member 41 and higher than the diffuse reflectance of the second light reflective member 42. The regular reflectance of the second light reflective member 42 is higher than the regular reflectance of the first light reflective member 41 and higher than the regular reflectance of the third light reflective member 43. The regular reflectance of the third light reflective member 43 is higher than the regular reflectance of the first light reflective member 41.

[0041] 1B, wiring 51 is disposed on the lower surface of first light reflective member 41. The lower surface of electrode 23 electrically connected to light emitting element 22 is exposed from first light reflective member 41 and connected to wiring 51. A pair of wirings 51 is disposed to connect to each of the pair of positive and negative electrodes 23, and the pair of wirings 51 are separated from each other on the lower surface of first light reflective member 41.

[0042] An insulating film 61 is disposed on the lower surface of the first light-reflective member 41. The insulating film 61 covers the outer periphery of the wiring 51. The portion of the wiring 51 that is inside the outer periphery is exposed from the insulating film 61. The insulating film 61 is also disposed between the pair of wirings 51, and improves the insulation between the pair of wirings 51.

[0043] Light from the light source 20 enters the light-guiding member 10 through the first light-transmissive member 31. The light that enters the light-guiding member 10 is guided within the light-guiding member 10 while repeatedly being totally reflected between the light-reflective member 40 and the first surface 11. Of the light guided within the light-guiding member 10, a portion of the light that travels toward the first surface 11 is extracted from the first surface 11 to the outside of the light-guiding member 10.

[0044] In the third region a3 where light reflective members 40 (second light reflective member 42 and third light reflective member 43) having a higher regular reflectance than first light reflective member 41 are arranged, light guided within light guiding member 10 is likely to be totally reflected on the second surface 12 side. This makes it easier for light from light source 20 to be guided within light guiding member 10 toward the ends and corners of light guiding member 10. As a result, the brightness of the region far from light source 20 can be improved, and brightness unevenness within the light emitting surface can be improved.

[0045] In the light-reflective member 40, a single layer portion of a third light-reflective member 43 having a higher diffuse reflectance than the second light-reflective member 42 is disposed in an area farther from the light source 20. Therefore, in the area farther from the light source 20, light guide due to total reflection is suppressed more than in the area where the second light-reflective member 42 is disposed, and light is mainly extracted from the first surface 11 by diffuse reflection, thereby improving the brightness in the area farther from the light source 20.

[0046] The second light reflective member 42 arranged in a region closer to the light source 20 than the single-layer portion of the third light reflective member 43 has a higher regular reflectance than the third light reflective member 43. Therefore, it is possible to prevent the light from the light source 20 from being extracted to the outside from the first surface 11 due to diffuse reflection before reaching the end or corner of the light guide member 10, and it is possible to easily guide the light from the light source 20 to a region in the light guide member 10 farther from the light source 20.

[0047] In this way, by combining the second light reflective member 42 and the third light reflective member 43, which have different reflective properties, as the light reflective member 40 arranged in the third region a3, it is possible to improve the efficiency of extracting light from the first surface 11 while ensuring light guidance.

[0048] In the first region a1 and the second region a2, which are closer to the light source 20 than the third region a3, the first light reflective member 41, which has a higher diffuse reflectance than the light reflective member 40, can reflect the downward light toward the first surface 11, thereby suppressing the light from escaping downward. Therefore, the brightness of the light extracted from the first surface 11 can be improved.

[0049] In the second region a2 around the light source 20, the light adjustment member 44 is disposed on the concave surface 11a. Therefore, part of the light emitted upward in the second region a2 around the light source 20 is reflected by the concave surface 11a and directed laterally. That is, part of the light directed upward in the second region a2 around the light source 20 is converted into a component that guides light within the light-guiding member 10, and the region above the light source 20 can be prevented from becoming too bright.

[0050] Next, a method for manufacturing the light emitting module 1 of the embodiment will be described with reference to FIGS.

[0051] The manufacturing method of the light emitting module 1 of the embodiment includes a step of preparing a laminate 101 shown in Fig. 4. The step of preparing the laminate 101 includes a step of preparing a light guiding member 10 and a step of arranging a light reflective member 40 on the second surface 12 of the light guiding member 10. Note that the step of preparing the laminate 101 may be performed by purchasing the laminate 101 in which the light reflective member 40 is arranged on the second surface 12 of the light guiding member 10.

[0052] A recess 14 (hereinafter referred to as a second recess) is formed in a first surface 11 of the light guiding member 10, and a first recess 13 is formed in a second surface 12 of the light guiding member 10. In a plan view of the first surface 11, the first recess 13 is formed at a position overlapping below the second recess 14. In addition, the shape of the opening of the first recess 13 and the second recess 14 in a plan view is circular in this embodiment, but may be, for example, elliptical, or may be polygonal, such as triangular, rectangular, hexagonal, or octagonal.

[0053] For example, a mold corresponding to the shape of the openings of the first recess 13 and the second recess 14 is prepared, and the plate-shaped light guiding member 10 is sandwiched between the mold and pressed to form the first recess 13 and the second recess 14. The first surface 11 and the second surface 12 are flat surfaces before the press process. Then, the press process deforms a part of the light guiding member 10 so that a part of the first surface 11 becomes a concave surface 11a and a part of the second surface 12 becomes a convex surface 12a. The deepest part of the concave surface 11a is located above the first recess 13. The convex surface 12a protrudes downward from the flat surface on the second surface 12 that is outside the convex surface 12a so as to follow the concave surface 11a.

[0054] After processing the light-guiding member 10 in this manner, the light-reflective member 40 is adhered to the second surface 12. The light-reflective member 40 has an opening 40a that exposes the first recess 13 and the convex surface 12a. The light-reflective member 40 is adhered to the second surface 12 of the light-guiding member 10 by, for example, an adhesive sheet. As the adhesive sheet, for example, an epoxy resin, an acrylic resin, a silicone resin, or an olefin resin can be used.

[0055] As described above, the light reflective member 40 includes the second light reflective member 42 and the third light reflective member 43. The second light reflective member 42 has a first opening 42a. A part of the third light reflective member 43 covers the second light reflective member 42. A step is formed between the part of the third light reflective member 43 bonded to the second surface 12 and the part covering the second light reflective member 42 (the part laminated on the second light reflective member 42). A second opening 43a that overlaps with the first opening 42a of the second light reflective member 42 is formed inside the part covering the second light reflective member 42 of the third light reflective member 43. The opening 40a of the light reflective member 40 is formed by communication between the first opening 42a and the second opening 43a.

[0056] 5, a light adjusting member 44 is formed in the second recess 14 of the first surface 11. For example, a light-transmitting resin containing a light diffusing agent is supplied in an uncured state to the second recess 14 by using a method such as dispensing or spraying, and then cured to form the light adjusting member 44.

[0057] 6, a first light-transmissive member 31 is formed in the first recess 13 of the second surface 12. For example, the first light-transmissive member 31 is supplied to the first recess 13 in an uncured state using a method such as dispensing or spraying. The first light-transmissive member 31 may contain a phosphor. It is preferable to supply the first recess 13 with an amount of the first light-transmissive member 31 that is equal to or smaller than the volume of the first recess 13.

[0058] As shown in FIG. 7, the light source 20 is disposed in the first recess 13. For example, after the first light-transmissive member 31 is supplied to the first recess 13, at least a part of the light source 20 is disposed in the uncured first light-transmissive member 31. Then, the first light-transmissive member 31 is cured. When the first light-transmissive member 31 is cured, the light source 20 sinks in the first light-transmissive member 31 by its own weight, or a load is applied to the light source 20 to sink it in the first light-transmissive member 31, so that, for example, the upper surface and side surface of the light source 20 are covered by the first light-transmissive member 31. At this time, the electrode 23 of the light source 20 is exposed from the first light-transmissive member 31. The light source 20 is fixed to the light-guiding member 10 by the first light-transmissive member 31.

[0059] After the light source 20 is fixed to the light guiding member 10, the light reflective member 40 may be bonded to the second surface 12 of the light guiding member 10. When a heat treatment is performed at, for example, 40° C. or more and 60° C. or less in order to increase the adhesive strength after the light reflective member 40 is bonded to the second surface 12 of the light guiding member 10, in order to prevent thermal damage to the light source 20, it is preferable to bond the light reflective member 40 to the second surface 12 of the light guiding member 10, perform the heat treatment, and then fix the light source 20 to the light guiding member 10.

[0060] The light reflective member 40 has an opening 40a that exposes the first recess 13. Therefore, even after the light reflective member 40 is bonded to the second surface 12 of the light guide member 10, it is possible to form the first light-transmissive member 31 in the first recess 13 and to arrange the light source 20 therein.

[0061] In the opening 40a, a convex surface 12a of the second surface 12 is exposed so as to surround the light source 20 in a plan view. A first light reflective member 41 shown in Fig. 8 is formed on the second surface 12 in the opening 40a, including the convex surface 12a. For example, the opening 40a is filled with the first light reflective member 41 so as to cover the electrode 23 of the light source 20 and the first light transmissive member 31, and then the first light reflective member 41 is ground to expose the surface of the electrode 23 from the first light reflective member 41.

[0062] An inner side surface of first light reflective member 41 contacts covering member 25 of light source 20, and an outer side surface of first light reflective member 41 contacts light reflective member 40. The thickness of the portion of first light reflective member 41 that contacts light reflective member 40 is thicker than the thickness of the portion of first light reflective member 41 that contacts covering member 25 of light source 20. The thickness of the portion of first light reflective member 41 that covers convex surface 12a gradually decreases toward light source 20.

[0063] After forming the first light reflective member 41, wiring 51 is formed on the surface of the first light reflective member 41 as shown in Fig. 9. For example, metal paste is supplied onto the surface of the first light reflective member 41 by a method such as printing and / or dispensing to form the wiring 51. The wiring 51 is connected to the electrodes 23 of the light source 20. The metal paste is also formed continuously between the pair of electrodes 23, and then separated between the pair of electrodes 23 by, for example, laser etching. A pair of wirings 51 connected to each of the pair of electrodes 23 is formed.

[0064] After forming the wirings 51, an insulating film 61 is formed on the surface of the first light reflective member 41, as shown in Fig. 10. The insulating film 61 is formed so as to cover at least the space between the pair of wirings 51, and can improve the insulation between the wirings 51. In the example shown in Fig. 10, the insulating film 61 is formed so as to cover the periphery of each of the pair of wirings 51, and can prevent the wirings 51 from peeling off the first light reflective member 41.

[0065] The above-described steps are performed on the sheet-like light guiding member 10 shown in FIG. 11. That is, a plurality of second recesses 14 are formed on the first surface 11 of the light guiding member 10. A plurality of first recesses 13 are formed on the second surface 12 of the light guiding member 10. A plurality of light reflective members 40 are attached separately to the second surface 12 of the light guiding member 10. A light adjustment member 44 is formed in each of the plurality of second recesses 14. A first light-transmissive member 31 is formed in each of the plurality of first recesses 13. A light source 20 is disposed in each of the plurality of first recesses 13. A first light reflective member 41 is formed in each of the openings 40a of the plurality of light reflective members 40.

[0066] Thereafter, the light-guiding member 10 is cut so as to include at least one light source 20 and at least one light-reflective member 40, thereby forming the light-emitting module 1 shown in FIGS. 1A, 1B, and 2. Note that one light-emitting module may include a plurality of light sources 20. Also, the light-emitting module 1 may be disposed on a wiring board to form a planar light source. The second surface 12 of the light-emitting module 1 faces the wiring board.

[0067] The first recess 13 for arranging the light source 20 is formed as a recess that opens in the second surface 12 in order to electrically connect the light source 20 to the outside. Like the first recess 13, the second recess for arranging the light adjustment member 44 may also be formed as a recess that opens in the first surface 11. However, as the light guide member 10 becomes thinner, the distance between the bottom surface of the first recess 13 and the first surface 11 becomes shorter, making it difficult to form a deep recess in the first surface 11 above the first recess 13.

[0068] According to this embodiment, by bending and deforming a part of the light guide member 10, a part of the first surface 11 formed as a flat surface is deformed into a concave surface 11a, and the second recess 14 in which the light adjustment member 44 can be disposed is formed. Therefore, even if the light guide member 10 becomes thin, a space for disposing the light adjustment member 44 can be secured. Furthermore, by storing the light adjustment member 44 in the second recess 14, an increase in the thickness of the entire light emitting module 1 can be suppressed.

[0069] The light emitting module of this embodiment has the following configuration. [Appendix 1] a light guiding member having a first surface and a second surface opposite to the first surface; a light source disposed on the second surface side of the light guiding member; a light adjustment member disposed on the first surface side at a portion overlapping with the light source in a plan view; A light reflective member disposed on the second surface side; Equipped with The light reflective member is a first light reflective member disposed near the light source and overlapping with the light adjustment member in a plan view; a second light reflective member disposed outside the first light reflective member in a plan view and having a lower diffuse reflectance than the first light reflective member; a third light reflective member disposed outside the second light reflective member in a plan view and having a higher diffuse reflectance than the second light reflective member; A light emitting module having [Appendix 2] 2. The light-emitting module according to claim 1, wherein the second light-reflective member includes a plurality of insulating films. [Appendix 3] 3. The light-emitting module according to claim 1, wherein a portion of the third light-reflective member extends so as to cover the second light-reflective member. [Appendix 4] 4. The light-emitting module according to claim 1, wherein the third light-reflective member has a diffuse reflectance lower than the diffuse reflectance of the first light-reflective member.

[0070] The above describes the embodiments of the present invention with reference to specific examples. However, the present invention is not limited to these specific examples. All forms that can be implemented by a person skilled in the art through appropriate design modifications based on the above-described embodiments of the present invention also belong to the scope of the present invention as long as they include the gist of the present invention. In addition, within the scope of the concept of the present invention, a person skilled in the art may come up with various modified examples and examples of modifications, and these modified examples and examples of modifications also belong to the scope of the present invention. [Explanation of symbols]

[0071] 1...light emitting module, 10...light guiding member, 11...first surface, 11a...concave surface, 12...second surface, 12a...convex surface, 13...concave (first concave), 14...concave (second concave), 20...light source, 22...light emitting element, 23...electrode, 24...second light transmissive member, 25...covering member, 31...first light transmissive member, 40...light reflective member, 41...first light reflective member, 42...second light reflective member, 43...third light reflective member, 44...light adjustment member, 51...wiring, a1...first region, a2...second region, a3...third region

Claims

1. a light guiding member having a first surface and a second surface opposite to the first surface, the light guiding member having a first region including a recess that opens into the second surface, a second region surrounding the first region in a plan view, and a third region surrounding the second region in a plan view; A light source disposed in the recess; Equipped with the first surface includes a concave surface disposed across the first region and the second region such that a deepest portion is located in the first region, the second surface includes a convex surface in the second region that protrudes from the third region so as to be aligned with the concave surface, a first light reflective member disposed on the convex surface; a second light reflecting member disposed in the third region of the second surface and having a lower diffuse reflectance for light from the light source than the first light reflecting member; The light emitting module further comprises:

2. The light emitting module according to claim 1 , further comprising a light adjusting member disposed on the concave surface.

3. The light emitting module according to claim 1 , wherein the first light reflective member is a resin member containing a light diffusing agent.

4. 4. The light emitting module according to claim 1, wherein the second light reflective member is a laminated member made of a plurality of insulating films.

5. The light-emitting module described in any one of claims 1 to 4, further comprising a third light-reflective member disposed in the third region of the second surface, surrounding the second light-reflective member in a planar view, and having a diffuse reflectance lower than that of the first light-reflective member and higher than that of the second light-reflective member for light from the light source.

6. The light emitting module according to claim 5 , wherein the third light reflective member extends so as to cover the second light reflective member.

7. The light emitting module according to claim 6 , wherein the third light reflective member is in contact with the first light reflective member.

8. 8. The light emitting module according to claim 5, wherein the third light reflective member is a resin member containing a plurality of bubbles.

9. A light-guiding member having a first surface and a second surface opposite to the first surface, the light-guiding member having a first region including a recess opening into the second surface, a second region surrounding the first region in a planar view, and a third region surrounding the second region in a planar view; A light source disposed in the recess; Equipped with the first surface includes a concave surface disposed across the first region and the second region such that a deepest portion is located in the first region, the second surface includes a convex surface in the second region that protrudes from the third region so as to be aligned with the concave surface, Further comprising a light adjusting member disposed on the concave surface, The light-emitting module, wherein the light adjustment member includes a light-transmitting resin and a light diffusing agent contained in the light-transmitting resin, and is disposed across the first region and the second region above the light source.

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