Surface light source manufacturing method, surface light source

Abstract

To improve adhesion reliability of a wall part and a substrate in a planer light source.SOLUTION: A manufacturing method of a present planer light source, includes: a step of arranging a plurality of light sources onto a substrate; a step of preparing a net-like partition member having a plurality of regions surrounded by a wall part; and a step of adhering the partition member to the substrate in a light reflection resin so as to circumference the light source by each wall part in a plan view. In the step of adhesion, the light reflection resin adheres at least one part of a side surface of the wall part and one part of a front surface of the substrate.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a method for manufacturing a surface light source and a surface light source. [Background technology]

[0002] Conventionally, a surface light source has been known that includes a wiring board on which multiple LED elements are mounted and a wall surrounding the LED elements, and the light emitted from the LED elements is reflected by the side surfaces of the wall. The wall is fixed to the wiring board by adhesive or the like. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2018-200375 Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure aims to improve the reliability of adhesion between a wall portion and a substrate in a surface light source. [Means for solving the problem]

[0005] A method for manufacturing a surface light source according to one embodiment of the present disclosure includes the steps of arranging a plurality of light sources on a substrate, preparing a mesh-like partition member having a plurality of areas surrounded by wall portions, and adhering the partition member to the substrate with a light-reflecting resin so that each of the wall portions surrounds the light source in a planar view, wherein in the adhering step, the light-reflecting resin adheres at least a portion of the side surface of the wall portion to a portion of the surface of the substrate.

[0006] Furthermore, a surface light source according to one embodiment of the present disclosure includes a substrate on which a plurality of light sources are arranged, a mesh-like partition member having a plurality of areas surrounded by wall portions, and a light-reflecting resin that adheres the partition member to the substrate, wherein, in a planar view, each of the wall portions of the partition member surrounds a light source, and the light-reflecting resin is positioned between at least a portion of the side surface of the wall portion and a portion of the surface of the substrate. [Effects of the Invention]

[0007] According to an embodiment of the present disclosure, in a surface light source, the reliability of adhesion between the wall portion and the substrate can be improved. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a plan view illustrating a surface light source according to a first embodiment. [Figure 2] 2 is a partially enlarged cross-sectional view taken along line II-II in FIG. 1, illustrating the surface light source according to the first embodiment. [Figure 3] 10A and 10B are diagrams illustrating an area on the side surface of a wall portion that is covered with a light reflecting resin. [Figure 4] 3 is a partially enlarged cross-sectional view of the light source and its vicinity in FIG. 2. FIG. [Figure 5] 1A and 1B are diagrams illustrating an example of the configuration of a light source in a surface light source. [Figure 6] 3A to 3C are schematic views (part 1) illustrating the manufacturing process of the surface light source according to the first embodiment. [Figure 7] 5A to 5C are schematic views (part 2) illustrating the manufacturing process of the surface light source according to the first embodiment. [Figure 8] 5A to 5C are schematic views (part 3) illustrating the manufacturing process of the surface light source according to the first embodiment. [Figure 9] 6A to 6C are schematic views (part 4) illustrating the manufacturing process of the surface light source according to the first embodiment. [Figure 10] 5A to 5C are schematic views illustrating the manufacturing process of the surface light source according to the first embodiment; [Figure 11] 6A to 6C are schematic views illustrating the manufacturing process of the surface light source according to the first embodiment; [Figure 12] FIG. 10 is a partially enlarged cross-sectional view (part 1) illustrating a surface light source according to a modified example of the first embodiment. [Figure 13] FIG. 10 is a partially enlarged cross-sectional view (part 2) illustrating a surface light source according to a modified example of the first embodiment. [Figure 14] FIG. 10 is a partially enlarged cross-sectional view (part 3) illustrating a surface light source according to a modified example of the first embodiment. [Figure 15] FIG. 10 is a partially enlarged cross-sectional view (part 1) illustrating a surface light source according to a second embodiment. [Figure 16] FIG. 10 is a partially enlarged cross-sectional view (part 2) illustrating the surface light source according to the second embodiment. [Figure 17] FIG. 10 is a configuration diagram illustrating a liquid crystal display device according to a third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, a description will be given of an embodiment of the invention 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) will 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 invention. Furthermore, parts that appear with the same reference numerals in multiple drawings indicate the same or equivalent parts or components.

[0010] Furthermore, the embodiments shown below are intended to exemplify surface light sources and the like to embody the technical concepts of the present invention, and are not intended to limit the present invention thereto. Furthermore, unless otherwise specified, the dimensions, materials, shapes, relative arrangements, etc. of the components described below are intended for illustrative purposes only and are not intended to limit the scope of the present invention. Furthermore, the content described in one embodiment may also be applied to other embodiments and modified examples. Furthermore, the size and positional relationships of components shown in the drawings may be exaggerated for clarity. Furthermore, to avoid overly complex drawings, schematic diagrams may be used in which some elements are omitted, or end views may be used as cross-sectional views showing only the cut surface.

[0011] First Embodiment (Surface light source 1) Fig. 1 is a plan view illustrating a surface light source according to a first embodiment. Fig. 2 is a partially enlarged cross-sectional view taken along line II-II in Fig. 1, illustrating the surface light source according to the first embodiment. For reference, Figs. 1 and 2 show mutually orthogonal X-, Y-, and Z-axes. In the subsequent figures, the mutually orthogonal X-, Y-, and Z-axes may also be shown.

[0012] As shown in FIGS. 1 and 2, the surface light source 1 is a surface-emitting light-emitting device having a substrate 10, a light source 20, a partition member 30, and a light-reflecting resin 40.

[0013] The substrate 10 has, for example, a rectangular shape in a plan view. A plurality of light sources 20 are arranged on the substrate 10. In this embodiment, 32 light sources 20 are arranged on the substrate 10, but this is just an example, and any number of light sources 20 may be arranged on the substrate 10.

[0014] The partitioning member 30 is disposed on the same side of the substrate 10 as the light source 20. The partitioning member 30 has a plurality of first wall portions 31 extending in a first direction and a plurality of second wall portions 32 extending in a second direction intersecting the first direction. In the example of FIG. 1, the first direction is the X direction, and the second direction is the Y direction. That is, in the example of FIG. 1, the first direction and the second direction are perpendicular to each other. The first wall portions 31 and the second wall portions 32 may be formed integrally or separately.

[0015] In a plan view, the region 30S is a region surrounded by two opposing first wall portions 31 and two opposing second wall portions 32. A plurality of regions 30S are arranged in the first direction and the second direction. In the example of FIG. 1, a plurality of regions 30S are arranged in the X direction and the Y direction. The light sources 20 are each arranged within the region 30S. In this way, the partitioning member 30 is a net-like (mesh-like) member having a plurality of regions 30S surrounded by the first wall portions 31 and the second wall portions 32, and in a plan view, each of the first wall portions 31 and the second wall portions 32 surrounds the light source 20.

[0016] The term "net-like" refers to a shape in which multiple regions are formed by walls extending in a first direction and a second direction. The walls are linear in the first direction or the second direction. The walls may also include bent or curved portions. The shape of the regions formed by the walls is square in plan view. Examples of shapes of the regions formed by the walls include rectangles, hexagons, circles, and ellipses. In one partition member, the shapes of the regions formed by the walls may all be the same shape, such as all squares, or two or more of these shapes may be mixed.

[0017] In a vertical cross section of the partition member 30 taken in the width direction of the first wall portion 31 (a direction parallel to the YZ plane in FIG. 1 ), the first wall portion 31 has a maximum width portion at a position different from the lowest portion in the thickness direction, and the width of the first wall portion 31 gradually decreases from the maximum width portion toward the lowest portion. In the vertical cross section of the first wall portion 31, the width of the first wall portion 31 may gradually decrease from the maximum width portion toward the highest portion. Hereinafter, the vertical cross section taken in the width direction of the first wall portion 31 may be simply referred to as the vertical cross section of the first wall portion 31. Furthermore, the shape of the first wall portion 31 in the vertical cross section taken in the width direction of the first wall portion 31 may be simply referred to as the vertical cross section shape of the first wall portion 31.

[0018] In a vertical cross section (e.g., the vertical cross section shown in FIG. 2 ) of the partition member 30 taken in the width direction of the second wall portion 32 (a direction parallel to the XZ plane in FIG. 1 ), the second wall portion 32 has a maximum width portion at a position different from the lowest portion in the thickness direction, and the width of the second wall portion 32 gradually decreases from the maximum width portion toward the lowest portion. In the vertical cross section of the second wall portion 32, the width of the second wall portion 32 may gradually decrease from the maximum width portion toward the highest portion. Hereinafter, the vertical cross section taken in the width direction of the second wall portion 32 may be simply referred to as the vertical cross section of the second wall portion 32. Furthermore, the shape of the second wall portion 32 in the vertical cross section taken in the width direction of the second wall portion 32 may be simply referred to as the vertical cross section shape of the second wall portion 32.

[0019] The cross-sectional shapes of the first wall portion 31 and the second wall portion 32 are each, for example, circular. The cross-sectional shapes of the first wall portion 31 and the second wall portion 32 may each, for example, be elliptical. The cross-sectional shape of the first wall portion 31 may be the same as or different from the cross-sectional shape of the second wall portion 32.

[0020] The width W of the widest portion of the first wall portion 31 and the second wall portion 32 in the longitudinal cross section of the first wall portion 31 and the second wall portion 32 can be, for example, about 0.1 mm or more and 5.0 mm or less. The first wall portion 31 and the second wall portion 32 may have a cavity therein. In that case, the widest portion of the first wall portion 31 and the second wall portion 32 is determined by the outer surface of the first wall portion 31 and the second wall portion 32. In other words, the width of the widest portion is the same whether the first wall portion 31 and the second wall portion 32 have a cavity therein or not.

[0021] The light reflecting resin 40 bonds the partition member 30 to the substrate 10. The light reflecting resin 40 is located between at least a part of the side surfaces of the first wall portion 31 and the second wall portion 32 and a part of the surface of the substrate 10.

[0022] In addition, when the vertical cross-sectional shape of the first wall portion 31 is circular or elliptical, the surfaces of the first wall portion 31 excluding both longitudinal end faces can be defined as side faces. The lowest part of the surfaces may also be defined as the bottom face. Similarly, when the vertical cross-sectional shape of the second wall portion 32 is circular or elliptical, the surfaces of the second wall portion 32 excluding both longitudinal end faces can be defined as side faces. The lowest part of the surfaces may also be defined as the bottom face.

[0023] In the longitudinal cross section of the first wall 31, the light reflecting resin 40 is preferably located between at least a part of the side surface of the first wall 31 located lowermost than the maximum width portion and a part of the surface of the substrate 10. In addition, in the longitudinal cross section of the second wall 32, the light reflecting resin 40 is preferably located between at least a part of the side surface of the second wall 32 located lower than the maximum width portion and a part of the surface of the substrate 10. This allows the light reflecting resin 40 to bond the substrate 10 to the first wall 31 and the second wall 32 with sufficient strength.

[0024] The light reflecting resin 40 may cover at least the entire side surface of the first wall portion 31 located lowermost than the maximum width portion in the vertical cross section of the first wall portion 31. The light reflecting resin 40 may also cover at least the entire side surface of the second wall portion 32 located lower than the maximum width portion in the vertical cross section of the second wall portion 32. This allows the light reflecting resin 40 to bond the substrate 10 to the first wall portion 31 and the second wall portion 32 with even more sufficient strength.

[0025] The light reflecting resin 40 may cover at least a part of the side surface of the first wall portion 31 located on the uppermost side of the maximum width portion in the vertical cross section of the first wall portion 31. The light reflecting resin 40 may also cover at least a part of the side surface of the second wall portion 32 located at least above the maximum width portion in the vertical cross section of the second wall portion 32. This allows the light reflecting resin 40 to bond the substrate 10 to the first wall portion 31 and the second wall portion 32 with even more sufficient strength.

[0026] 3, the light reflecting resin 40 may cover the entire side surfaces of the first wall portion 31 and the second wall portion 32. This allows the light reflecting resin 40 to bond the substrate 10 to the first wall portion 31 and the second wall portion 32 with even more sufficient strength. Furthermore, when the reflectance of the first wall portion 31 and the second wall portion 32 is lower than the reflectance of the light reflecting resin 40, the reflectance of the portion surrounding the light source 20 can be improved, which is suitable when the partition member 30 and the light reflecting resin 40 are used as a reflector.

[0027] It is preferable that the light reflecting resin 40 is wider on the lower side in a cross-sectional view. That is, it is preferable that the light reflecting resin 40 has a shape in which the thickness gradually decreases with increasing distance from the first wall portion 31 and the second wall portion 32, and is thinnest at the portion farthest from the first wall portion 31 and the second wall portion 32. This allows the light emitted from the light source 20 to be reflected upward and sideways, thereby suppressing the occurrence of uneven brightness and color in the surface light source 1. Note that the light reflecting resin 40 may have a shape in which the thickness gradually decreases linearly with increasing distance from the first wall portion 31 and the second wall portion 32, or may have a shape in which the thickness gradually decreases in a concave curve or a convex curve.

[0028] Each element constituting the surface light source 1 will be described in detail below.

[0029] (Substrate 10) Fig. 4 is a partially enlarged cross-sectional view of the light source and its vicinity in Fig. 2. The substrate 10 is a member on which a plurality of light sources 20 are mounted. As shown in Fig. 4, the substrate 10 includes at least a base material 11 and conductive wirings 18A and 18B disposed on an upper surface 11a of the base material 11. The conductive wirings 18A and 18B are for supplying power to the light source 20 including the light-emitting element 21. The substrate 10 may further include a covering member 15 on the upper surface 11a of the base material 11 and on parts of the conductive wirings 18A and 18B that are not electrically connected to the light-emitting element 21.

[0030] The material of the substrate 10 may be any material that can insulate and separate at least one pair of conductor wirings 18A and 18B, and examples thereof 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 the above-mentioned resins mixed with reflective materials such as glass fiber, TiO2, Al2O3, SiO2, ZrO2, MgO, and ZnO, glass fiber reinforced resins (glass epoxy resins), and metal substrates in which a metal member is coated with an insulating layer.

[0031] The thickness of the substrate 10 can be selected as appropriate. The substrate 10 may be either a flexible substrate that can be manufactured by a roll-to-roll method or a rigid substrate. The rigid substrate may be a thin, bendable rigid substrate. The materials of the conductor wirings 18A and 18B are not particularly limited as long as they are conductive members, and materials that are normally used for wiring layers of circuit boards and the like can be used.

[0032] The covering member 15 is preferably made of an insulating material. Examples of materials for the covering member 15 include the same materials as those exemplified as materials for the substrate 10. By using the above-mentioned resin containing a reflective material or a large number of bubbles as the covering member 15, the light emitted from the light source 20 is reflected, thereby improving the light extraction efficiency of the surface light source 1. This is particularly effective when there is a gap between the sealing member 22 and the light-reflecting resin 40 described below.

[0033] (light source 20) The light source 20 is a light-emitting component, and includes, for example, a light-emitting element that emits light itself, a light-emitting element sealed with a translucent resin or the like, and a surface-mounted light-emitting device (also called an LED) in which a light-emitting element is packaged. The light-emitting element 21 may be, for example, one that emits blue light. As shown in FIG. 4, an example of the light source 20 is one in which a light-emitting element 21 is covered with a sealing member 22. Another example of the light source 20 is one that contains a phosphor. By including a phosphor, it is possible to emit light of a color different from the color emitted by the light-emitting element itself, such as magenta or white. For white light, it is possible to emit light of various color temperatures, such as daylight white or warm white.

[0034] Furthermore, the light source 20 may have one light-emitting element 21 as shown in Fig. 4, or may have multiple light-emitting elements 21 as shown in Fig. 5. In this case, for example, two or more light-emitting elements of the same color may be arranged in one region 30S. Alternatively, multiple light-emitting elements including red, green, and blue light-emitting elements may be arranged in one region 30S. Alternatively, one region 30S may have arranged therein a light source that contains a phosphor and emits daylight white light, and a light source that contains a phosphor and emits warm white light.

[0035] The light source 20, in which the light-emitting element is sealed with a translucent resin or the like, may be configured to include a resin containing a light-reflective material that surrounds the side surfaces of the light-emitting element 21 and a translucent member that covers the top surface of the light-emitting element 21 and the top surface of the resin containing the light-reflective material. Alternatively, the light source 20 may be configured to include a translucent member that covers the top surface of the light-emitting element 21 and a resin containing a light-reflective material that surrounds the side surfaces of the light-emitting element 21 and the side surfaces of the translucent member. Alternatively, the light source 20 may be configured to include a translucent member that integrally covers the side surfaces and top surface of the light-emitting element 21. Here, either of the translucent members may be a translucent member containing a phosphor. In either of the light source configurations, a second translucent member may be provided on the top surface. The second translucent member may be a translucent member containing a light diffusing material, and by adjusting the concentration and thickness, a light source with a batwing light distribution may be achieved. A translucent adhesive member that adheres the light-emitting element 21 to the translucent member may be provided between the light-emitting element 21 and the translucent member.

[0036] It is preferable that the light sources 20 have a wide light distribution so that they emit light with little unevenness in brightness in each region 30S of the partitioning member 30. In particular, it is preferable that each of the light sources 20 has a batwing light distribution characteristic. This reduces the amount of light emitted directly above the light source 20, widens the light distribution of each light source 20, and irradiates the partitioning member 30 and the light reflecting resin 40 with the widened light, thereby reducing unevenness in brightness in each region 30S.

[0037] Here, the batwing light distribution characteristic is defined as having an emission intensity distribution in which, with the optical axis OA set to 0 degrees, the emission intensity is stronger at angles where the absolute value of the light distribution angle is greater than 0 degrees. Note that the optical axis OA is defined as a line that passes through the center of light source 20 and perpendicularly intersects with top surface 11a of substrate 11, as shown in FIG. 4.

[0038] In particular, as shown in Fig. 4, an example of a light source 20 having a batwing light distribution characteristic is one that uses a light-emitting element 21 having a light-reflecting film 23 on its upper surface. By providing the light-reflecting film 23 on the upper surface of the light-emitting element 21, most of the light emitted upward from the light-emitting element 21 is reflected by the light-reflecting film 23, thereby reducing the amount of light directly above the light-emitting element 21 and achieving a batwing light distribution characteristic. A lens may also be separately combined to achieve the batwing light distribution.

[0039] The light-reflecting film 23 may be any of a metal film such as silver or copper, a resin containing a reflective material, or a combination thereof. Examples of reflective materials contained in the resin include TiO2, Al2O3, SiO2, ZrO2, MgO, and ZnO. The light-reflecting film 23 may also be a dielectric multilayer film (DBR film). Specifically, it is preferable to set the reflectance of the light-reflecting film 23 so that it is lower for oblique incidence than for normal incidence. This makes it possible to moderate the change in luminance directly above the light-emitting element 21 and prevent the area directly above the light-emitting element 21 from becoming extremely dark, such as a dark spot.

[0040] The light source 20 may have, for example, a light emitting element 21 mounted on the substrate 10 with a height of 100 μm to 500 μm. The light reflecting film 23 may have a thickness of 0.1 μm to 3.0 μm. The thickness of the light source 20, including the sealing member 22, can be approximately 0.5 mm to 2.0 mm.

[0041] The plurality of light sources 20 can be driven independently of one another, and are preferably wired on the substrate 10 so that dimming control (for example, local dimming or high dynamic range) for each light source 20 is possible.

[0042] Known light-emitting elements 21 can be used. For example, light-emitting diodes can be used as the light-emitting elements 21. Light-emitting elements 21 with any wavelength can be selected. For example, blue and green light-emitting elements can be made of nitride-based semiconductors such as GaN, InGaN, AlGaN, and AlInGaN. Red light-emitting elements can be made of GaAlAs, AlInGaP, and the like. Semiconductor light-emitting elements made of other materials can also be used. The composition, light-emitting color, size, number, and the like of the light-emitting elements used can be selected appropriately depending on the purpose.

[0043] 4, the light emitting element 21 may be flip-chip mounted via a bonding member 19 so as to straddle a pair of positive and negative conductor wirings 18A and 18B provided on the upper surface 11a of the base material 11. However, the light emitting element 21 may be not only flip-chip mounted but also face-up mounted.

[0044] The bonding member 19 is a member for bonding the light-emitting element 21 to a substrate or conductive wiring, and may be made of an insulating resin or a conductive member. In the case of flip-chip mounting as shown in Fig. 4, a conductive member is used. Specific examples include an Au-containing alloy, an Ag-containing alloy, a Pd-containing alloy, an In-containing alloy, a Pb-Pd-containing alloy, an Au-Ga-containing alloy, an Au-Sn-containing alloy, an Sn-containing alloy, an Sn-Cu-containing alloy, an Sn-Cu-Ag-containing alloy, an Au-Ge-containing alloy, an Au-Si-containing alloy, an Al-containing alloy, a Cu-In-containing alloy, and a mixture of a metal and flux.

[0045] The sealing member 22 covers the light-emitting element 21 for the purposes of protecting the light-emitting element 21 from the external environment and optically controlling the light emitted from the light-emitting element 21 (for example, to obtain bad wing light distribution characteristics). The sealing member 22 is made of a light-transmitting material. Examples of materials that can be used for the sealing member 22 include light-transmitting resins such as epoxy resin, silicone resin, or a mixture thereof, and glass. Of these, silicone resin is preferred in view of its light resistance and ease of molding. The sealing member 22 may contain a diffusing agent for diffusing the light from the light-emitting element 21, a coloring agent corresponding to the light-emission color of the light-emitting element 21, and the like. Diffusing agents, coloring agents, and the like that are known in the art can be used.

[0046] The sealing member 22 can be in direct contact with the substrate 10. Examples of the shape of the sealing member 22 include, but are not limited to, a substantially hemispherical shape, a vertically elongated convex shape in cross-section, a flattened convex shape in cross-section, and a circular or elliptical shape in plan view. Here, a vertically elongated convex shape refers to a shape in which, in cross-section, the maximum length in a direction perpendicular to the upper surface 11a of the substrate 11 is longer than the maximum length in a direction parallel to the upper surface 11a of the substrate 11. Furthermore, a flattened convex shape refers to a shape in which, in cross-section, the maximum length in a direction parallel to the upper surface 11a of the substrate 11 is longer than the maximum length in a direction perpendicular to the upper surface 11a of the substrate 11. The sealing member 22 may be disposed between the lower surface of the light-emitting element 21 and the upper surface 11a of the substrate 11.

[0047] When the light-transmitting member of the light source 20 contains a phosphor, the phosphor may be an yttrium-aluminum-garnet phosphor (for example, 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-based phosphors (e.g., Ca 10 (PO4)6C l2 :Eu), SAE-based 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., Mz(Si,Al) 12 (O,N) 16 :Eu (where 0 < z ≤ 2 and M is Li, Mg, Ca, Y, and lanthanide elements excluding La and Ce)), nitride phosphors such as SLA phosphors (e.g., SrLiAl3N4:Eu), CASN phosphors (e.g., CaAlSiN3:Eu) or SCASN phosphors (e.g., (Sr,Ca)AlSiN3:Eu), fluoride phosphors such as KSF phosphors (e.g., K2SiF6:Mn), KSAF phosphors (e.g., K2(Si,Al)F6:Mn) or MGF phosphors (e.g., 3.5MgO·0.5MgF2·GeO2:Mn), phosphors having a perovskite structure (e.g., CsPb(F,Cl,Br,I)3), or quantum dot phosphors (e.g., CdSe, InP, AgInS2 or AgInSe2) etc. can be used.

[0048] (Partition member 30) The partitioning member 30 is disposed on the substrate 10. The partitioning member 30 is adhered to the substrate 10 using a light-reflecting resin 40 as an adhesive. The light source 20 is disposed within the partition (the area surrounded by the first wall portion 31 and the second wall portion 32) of the partitioning member 30, and the partitioning member 30 reduces unevenness in brightness of the light emitted upward from the partition. The partitioning member 30 may be formed from a light-reflecting resin. Specifically, it is preferable to use a resin containing a reflective material such as TiO2, Al2O3, SiO2, ZrO2, MgO, or ZnO. The partitioning member 30 may also be formed from a non-light-reflecting resin. Furthermore, a metal wire or a metal plate with multiple openings may be used. Specific materials for the wire or metal plate include Ag, Al, and Au. Furthermore, the partitioning member 30 may have a light-reflecting film formed on the surface of such a resin or metal. The light-reflecting film may be a resin or a metal. Furthermore, when metal wires are used as the partitioning member 30, a member formed by weaving together a plurality of first wires extending in a certain direction and a plurality of second wires extending in a direction intersecting the first wires can be used. In this case, the first wall portion is formed from the first wires, and the second wall portion is formed from the second wires, resulting in a partitioning member 30 in which the first wall portion and the second wall portion are formed separately.

[0049] The partitioning member 30 itself has light reflectivity, and therefore the reflectance of the light emitted from the light source 20 can be increased, so that the partitioning member 30 can be suitably used as a reflector.

[0050] If the partitioning member 30 itself does not have light reflectivity, it is preferable that the entire side surface of the partitioning member 30 be covered with the light reflecting resin 40 .

[0051] In the partitioning member 30, the pitch between adjacent first wall portions 31 and the pitch between adjacent second wall portions 32 can be adjusted as appropriate depending on the size of the light source 20 used, the size of the intended surface light source 1, and the like. The pitch between adjacent first wall portions 31 and the pitch between adjacent second wall portions 32 are, for example, 1 mm to 50 mm, preferably 5 mm to 20 mm, and more preferably 6 mm to 15 mm. The pitch is defined as the distance between the centers of adjacent first wall portions 31 in the width direction in a cross-sectional view. Similarly, the pitch is defined as the distance between the centers of adjacent second wall portions 32 in the width direction in a cross-sectional view. The height H of the partitioning member 30 itself, i.e., the length in the Z direction of each of the first wall portions 31 and the second wall portions 32, is preferably 8 mm or less, and is preferably approximately 1 mm to 4 mm when a thinner surface light source 1 is desired.

[0052] In the partitioning member 30, the number of regions 30S can be set arbitrarily depending on the size of the surface light source 1. The partitioning member 30 is preferably light-reflective. The partitioning member 30 can be formed, for example, from a light-reflective resin. This allows the first wall portion 31 and / or the second wall portion 32 to efficiently reflect the light emitted from the light source 20 even when a portion of the first wall portion 31 and / or the second wall portion 32 is exposed from the light-reflecting resin 40. In this case, the partitioning member 30 is preferably set so that the reflectance of the light emitted from the light source 20 is 70% or more.

[0053] (light-reflecting resin) The light-reflecting resin 40 is an adhesive material that bonds the substrate 10 and the partition member 30. The light-reflecting resin 40 is a material that can efficiently reflect light from the light source 20 and is provided to surround the light source 20. The light-reflecting resin 40 may or may not be in contact with the sealing member 22. The light-reflecting resin 40 is preferably in contact with the sealing member 22. This allows the light emitted from the light source 20 to be efficiently reflected. A specific material that constitutes the light-reflecting resin 40 is preferably an insulating material, and more preferably a material that is less likely to transmit or absorb light from the light source 20 or external light. For example, a thermosetting resin or a thermoplastic resin can be used as the light-reflecting resin 40. More specifically, the light-reflecting resin 40 is preferably a resin such as a phenolic resin, an epoxy resin, a BT resin, a PPA resin, or a silicone resin, with a powder of a reflective material dispersed in the resin that is less likely to absorb light from the light source 20 and has a refractive index significantly different from that of the resin used as the base material. This allows the light from the light source 20 to be efficiently reflected. Examples of the reflective material dispersed in the matrix include TiO2, Al2O3, SiO2, ZrO2, MgO, and ZnO.

[0054] (Method of manufacturing a surface light source) The method for manufacturing the surface light source 1 includes the steps of arranging a plurality of light sources on a substrate, preparing a mesh-like partition member having a plurality of regions surrounded by walls, and adhering the partition member to the substrate with a light-reflecting resin so that each wall surrounds a light source in a plan view. In the adhering step, the light-reflecting resin adheres at least a portion of the side surface of the wall member to a portion of the surface of the substrate.

[0055] 6 to 11 are schematic views illustrating the manufacturing process of the surface light source according to the first embodiment. Hereinafter, the manufacturing method of the surface light source 1 will be described with reference to FIGS.

[0056] (Process 1) In step 1, as shown in FIG. 6, a plurality of light sources 20 are arranged on the substrate 10. First, conductor wirings 18A and conductor wirings 18B are alternately arranged at predetermined intervals on the upper surface 11a of the base material 11, and are aligned, for example, in a matrix direction to obtain the substrate 10. Examples of methods for forming the conductor wirings 18A and 18B include plating and vapor phase film formation methods (sputtering, ion plating, electron beam evaporation, vacuum evaporation, chemical vapor deposition, etc.). The conductor wirings 18A and 18B may also be formed by adhering a metal foil or the like to the upper surface 11a of the base material 11 and patterning it by etching.

[0057] Next, as necessary, the upper surface 11a of the base material 11 and portions of the conductor wirings 18A and 18B that are not electrically connected to the light emitting element 21 are covered with a covering member 15. The covering member 15 can be formed, for example, by a screen printing method using a mask or the like so that portions of the conductor wirings 18A and 18B are exposed. The covering member 15 may also be formed by an inkjet method, laminating a resin sheet, or other methods. The substrate 10 may also be prepared by purchase.

[0058] Next, a plurality of light-emitting elements 21 are prepared. Each light-emitting element 21 may have a light-reflecting film 23 on its upper surface. Each light-emitting element 21 is then arranged on the substrate 10 so that the two electrodes of each light-emitting element 21 are in contact with the bonding member 19. Subsequently, the bonding member 19 is melted in a reflow furnace to connect one electrode of each light-emitting element 21 to the conductor wiring 18A with the bonding member 19, and also connect the other electrode to the conductor wiring 18B with the bonding member 19. Next, a sealing member 22 that covers each light-emitting element 21 is formed by printing or application with a dispenser, and is cured by heat treatment or light irradiation. In this way, a plurality of light sources 20 are arranged on the substrate 10.

[0059] (Process 2) In step 2, as shown in Fig. 7, a mesh-like partition member 30 is prepared, which has a plurality of regions 30S surrounded by a first wall portion 31 and a second wall portion 32. In a longitudinal cross section cut in the width direction of the first wall portion 31, the partition member 30 preferably has a maximum width portion at a position different from the bottom in the thickness direction, and the width of the first wall portion 31 gradually decreases from the maximum width portion toward the bottom. In the longitudinal cross section of the first wall portion 31, the width of the first wall portion 31 may gradually decrease from the maximum width portion toward the top. In the longitudinal cross section of the first wall portion 31, the first wall portion 31 is, for example, circular or elliptical.

[0060] In addition, in a longitudinal cross section of the partition member 30 taken in the width direction of the second wall portion 32, it is preferable that the second wall portion 32 has a maximum width portion at a position different from the lowest portion in the thickness direction, and the width of the second wall portion 32 gradually decreases from the maximum width portion toward the lowest portion. In the longitudinal cross section of the second wall portion 32, the width of the second wall portion 32 may gradually decrease from the maximum width portion toward the highest portion. In the longitudinal cross section of the second wall portion 32, the second wall portion 32 is, for example, circular or elliptical.

[0061] When a resin is used, the partition member 30 can be produced by, for example, injection molding the resin. After the resin is injection molded, a light-reflective film can be formed on the surface of the resin. When the film is a resin, it can be formed by, for example, immersing the film in a resin containing a reflective material. When the film is a metal, it can be formed by, for example, a vapor deposition method. The partition member 30 may also be prepared by purchasing.

[0062] (Step 3) In step 3, as shown in Figures 8 to 11, the partitioning member 30 is bonded to the substrate 10 with light reflecting resin 40 so that the first wall portions 31 and second wall portions 32 surround the light source 20 in a plan view. First, as shown in Figures 8 to 10, the light reflecting resin 40 is formed in, for example, a grid pattern on the upper surface of the substrate 10 at positions where the partitioning member 30 will be disposed. Here, a method of forming the light reflecting resin 40 using a resin discharge device 500 will be exemplified.

[0063] The resin discharging device 500 can be moved (moved) in a vertical or horizontal direction relative to the fixed substrate 10, for example, above the substrate 10. A main body (not shown) equipped with the resin discharging device 500 is mainly equipped with a syringe for storing the resin, a regulator for controlling the discharging pressure, and the like. In this specification, other parts are omitted and the nozzle 510 from which the resin is discharged is illustrated as the resin discharging device 500, and the following steps will be mainly explained using this part. Note that although an example using one resin discharging device 500 is shown and explained in FIGS. 8 and 9, this is not limiting, and multiple resin discharging devices 500 can be provided on the main body. This allows multiple light-reflecting resins to be formed simultaneously.

[0064] The line width of the discharged resin is preferably 0.2 mm to 2.0 mm, more preferably 0.5 mm to 1.0 mm. In this case, a nozzle with multiple discharge ports may be used to draw multiple lines on one wall. Also, multiple drawings may be performed on one wall, overlapping multiple layers.

[0065] First, as shown in FIG. 8, multiple rows of uncured light reflecting resin 40A are formed parallel to the Y direction. Specifically, for example, the resin discharging device 500 is moved in a first direction 1a parallel to the Y direction to form the first row of light reflecting resin 40A. After moving the resin discharging device 500 a predetermined distance in the X direction, the resin discharging device 500 is again moved in the first direction 1a to form the second row of light reflecting resin 40A. By repeating this process, uncured light reflecting resin 40A extending in the Y direction can be formed at predetermined intervals in the X direction. Note that after moving the resin discharging device 500 in the first direction 1a, the resin discharging device 500 may be moved in the opposite direction to the first direction 1a for the next row.

[0066] Next, as shown in FIG. 9, multiple rows of uncured light reflecting resin 40B are formed parallel to the X direction. Specifically, for example, the resin discharging device 500 is moved in a second direction 1b parallel to the X direction to form the first row of light reflecting resin 40B. After moving the resin discharging device 500 a predetermined distance in the Y direction, the resin discharging device 500 is again moved in the second direction 1b to form the second row of light reflecting resin 40B. By repeating this process, uncured light reflecting resin 40B extending in the X direction can be formed at predetermined intervals in the Y direction. Note that after moving the resin discharging device 500 in the second direction 1b, the resin discharging device 500 may be moved in the opposite direction to the second direction 1b for the next row.

[0067] 8 and 9, the resin is drawn and formed to form uncured light-reflecting resins 40A and 40B on the upper surface of the substrate 10 at the position where the partition member 30 is to be disposed. FIG. 10 shows a cross-sectional view of the substrate 10 shown in FIG. 9, cut in a direction parallel to the XZ plane through the center of the light source 20. In the process shown in FIGS. 8 and 9, the moving speed of the resin-discharging device 500 can be adjusted as appropriate depending on the viscosity and temperature of the resin used. To ensure that the formed light-reflecting resins 40A and 40B each have approximately the same width, it is preferable to move the resin at a constant speed at least while discharging. When the resin-discharging device 500 temporarily stops discharging the resin, the moving speed during that time can be changed. It is also preferable to keep the amount of resin discharged constant. Furthermore, it is preferable to keep both the moving speed of the resin-discharging device 500 and the amount of resin discharged constant. The amount of resin discharged can be adjusted by, for example, maintaining constant the pressure applied during discharging.

[0068] This partitioning member 30 can be formed, for example, by preparing a support having a flat upper surface and forming a mesh-like layer of uncured resin on the upper surface of the support by the method shown in Figures 8 and 9. After the resin is cured on the support, it is peeled off from the support. This completes the resin partitioning member 30. The completed partitioning member 30 may be mounted on the substrate 10 with the side that was in contact with the support facing the substrate 10, or with the side that was in contact with the support facing away from the substrate 10.

[0069] 11, the partitioning member 30 is placed on the uncured light reflecting resins 40A and 40B and pressure is applied in the direction of the arrow. For example, pressure is applied to the partitioning member 30 until the underside of the partitioning member 30 contacts the upper surface of the covering member 15 formed on the substrate 10, and then the light reflecting resins 40A and 40B are cured. For example, a thermosetting resin is used for the light reflecting resins 40A and 40B, and the light reflecting resins 40A and 40B are heated to a curing temperature or higher to cure, thereby forming the light reflecting resin 40.

[0070] The light reflecting resin 40 bonds at least a part of the side surfaces of the first wall portion 31 and the second wall portion 32 to a part of the surface of the substrate 10. It is preferable that the light reflecting resin 40 bonds at least a part of the side surfaces of the first wall portion 31 and the second wall portion 32 located below the maximum width portion to a part of the surface of the substrate 10.

[0071] Thus, in the surface light source 1, the light reflecting resin 40 bonds at least a portion of the side surfaces of the first wall portion 31 and the second wall portion 32 to a portion of the surface of the substrate 10. This allows the light reflecting resin 40 to be in contact with the first wall portion 31 and the second wall portion 32 and the substrate 10 over a wide area, thereby improving the reliability of bonding between the first wall portion 31 and the second wall portion 32 and the substrate 10. Furthermore, since the light emitted by the light source 20 is reflected by the light reflecting resin 40, the brightness of the surface light source 1 can be improved.

[0072] 8 to 10. For example, the partitioning member 30 shown in Fig. 7 may be placed directly on the substrate 10 so that the first wall portion 31 and the second wall portion 32 surround each light source 20, and then the light reflecting resin 40 may be discharged onto the partitioning member 30 from above the substrate 10 using a resin discharging device 500.

[0073] Alternatively, the partitioning member 30 may be immersed in uncured light-reflecting resin beforehand, and the partitioning member 30 soaked in the uncured light-reflecting resin may then be placed on the substrate 10, after which the uncured light-reflecting resin may be cured to form the light-reflecting resin 40. When the partitioning member 30 soaked in the uncured light-reflecting resin is placed on the substrate 10, the uncured light-reflecting resin spreads on the side of the partitioning member 30 closer to the substrate 10, so that, for example, the width of the partitioning member 30 increases toward the lower side in a cross-sectional view. By curing the uncured light-reflecting resin in this state, the light-reflecting resin 40 having the shape shown in FIG. 2 may be formed.

[0074] <Modification of the first embodiment> In the modified example of the first embodiment, variations in the longitudinal cross-sectional shapes of the first wall portion and the second wall portion of the partition member are shown. Figures 12 to 14 are partially enlarged cross-sectional views illustrating examples of surface light sources according to modified examples of the first embodiment. Figures 12 to 14 show cross sections corresponding to Figure 2.

[0075] As in the partition member 30A shown in FIG. 12, the vertical cross-sectional shape of the second wall portion 32 may be such that the widest portion of the second wall portion 32 is located at the top of the second wall portion 32 and the narrowest portion of the second wall portion 32 is located at the bottom of the second wall portion 32. In this case, the width of the second wall portion 32 may gradually decrease from the widest portion toward the bottom. The same applies to the vertical cross-sectional shape of the first wall portion 31 (not shown). The vertical cross-sectional shapes of the first wall portion 31 and the second wall portion 32 are, for example, shapes obtained by turning a truncated cone upside down. The side surfaces of the first wall portion 31 and the second wall portion 32 may be flat, curved, or a mixture of flat and curved surfaces.

[0076] 13, the cross-sectional shape of the second wall portion 32 may be such that the widest portion of the second wall portion 32 is located at either the top or bottom of the second wall portion 32, and the narrowest portion of the second wall portion 32 is located between the top and bottom of the second wall portion 32. In this case, the width of the second wall portion 32 may gradually decrease from the top to the narrowest portion and from the bottom to the narrowest portion. The same applies to the cross-sectional shape of the first wall portion 31 (not shown). The cross-sectional shapes of the first wall portion 31 and the second wall portion 32 may be, for example, a truncated cone shape and an inverted truncated cone shape connected at the narrowest portion. The side surfaces of the first wall portion 31 and the second wall portion 32 may be flat, curved, or a mixture of flat and curved surfaces.

[0077] 14, the cross-sectional shape of the second wall portion 32 may be rectangular, trapezoidal, or triangular. The same applies to the cross-sectional shape of the first wall portion 31 (not shown). In this case, the width of the first wall portion 31 and the width of the second wall portion 32 are constant from the top to the bottom.

[0078] In any of the cases of the partitioning members 30A, 30B, and 30C, if only the bottom surfaces of the first wall portion 31 and the second wall portion 32 were bonded to the surface of the substrate 10, the light reflecting resin 40 would not be able to contact the first wall portion 31 and the second wall portion 32 and the substrate 10 over a large area, making it difficult to increase the adhesive strength between the first wall portion 31 and the second wall portion 32 and the substrate 10. In contrast, by bonding the light reflecting resin 40 to at least a part of the side surfaces of the first wall portion 31 and the second wall portion 32 and a part of the surface of the substrate 10, the light reflecting resin 40 can contact the first wall portion 31 and the second wall portion 32 and the substrate 10 over a large area, thereby improving the adhesive reliability between the first wall portion 31 and the second wall portion 32 and the substrate 10.

[0079] In any of the partition members 30A, 30B, and 30C, the light reflecting resin 40 preferably covers the side surfaces of the first wall portion 31 and the second wall portion 32 up to a height that is at least half the height of the top of the first wall portion 31 and the second wall portion 32. This allows the light reflecting resin 40 to be in contact with the first wall portion 31 and the second wall portion 32 and the substrate 10 over a wider area, thereby further improving the reliability of adhesion between the first wall portion 31 and the second wall portion 32 and the substrate 10.

[0080] In any of the partitioning members 30A, 30B, and 30C, the light reflecting resin 40 may cover the entire side and top surfaces of the first wall portion 31 and the second wall portion 32. This allows the light reflecting resin 40 to be in contact with the first wall portion 31 and the second wall portion 32 and the substrate 10 over a wider area, thereby further improving the reliability of adhesion between the first wall portion 31 and the second wall portion 32 and the substrate 10. Furthermore, when the reflectance of the first wall portion 31 and the second wall portion 32 is lower than the reflectance of the light reflecting resin 40, the reflectance of the portion surrounding the light source 20 can be improved, making this suitable for use of each partitioning member and the light reflecting resin 40 as a reflector.

[0081] In any of the partitioning members 30A, 30B, and 30C, the light reflecting resin 40 may be provided between the bottom surface of the first wall portion 31 and / or the second wall portion 32 and the surface of the substrate 10. In this case, the light reflecting resin 40 bonds at least a part of the side surface of the first wall portion 31 and the second wall portion 32 to a part of the surface of the substrate 10, thereby achieving the same effect as above.

[0082] Second Embodiment In the second embodiment, an example is shown in which the surface light source has an optical member such as a diffuser plate. FIG. 15 is a partially enlarged cross-sectional view (part 1) illustrating the surface light source according to the second embodiment. FIG. 15 shows a cross section corresponding to FIG. 2. As shown in FIG. 15, the surface light source 2 has a diffuser plate 61 arranged above the light source 20 with the partition member 30 sandwiched therebetween. The diffuser plate 61 is arranged, for example, above the light source 20 so as to be in contact with the first wall portion 31 and the second wall portion 32. By including the diffuser plate 61 in the surface light source 1, the uniformity of light can be improved. The diffuser plate 61 does not have to be in contact with the first wall portion 31 and the second wall portion 32.

[0083] (Diffuser 61) The diffusion plate 61 is a member that diffuses and transmits incident light, and one diffusion plate 61 can be disposed above the plurality of light sources 20 as needed. The diffusion plate 61 is preferably a flat plate-like member. The surface of the diffusion plate 61 may also have an uneven surface. The diffusion plate 61 is preferably disposed substantially parallel to the substrate 10.

[0084] The diffusion plate 61 can be made of a material that has little light absorption for visible light, such as polycarbonate resin, polystyrene resin, acrylic resin, or polyethylene resin. To diffuse the incident light, the diffusion plate 61 may have materials with different refractive indices dispersed therein, and the diffusion plate 61 does not need to contain materials with different refractive indices as long as it has a diffusing function, such as by providing irregularities on its surface. The irregularities can have a size of, for example, 0.01 mm to 0.1 mm. The material with different refractive index can be selected from, for example, polycarbonate resin, acrylic resin, etc.

[0085] The thickness and degree of light diffusion of the diffusion plate 61 can be set appropriately, and commercially available materials such as light diffusion sheets, diffuser films, etc. For example, the thickness of the diffusion plate 61 can be set to 1 mm to 2 mm.

[0086] For example, if the vertical cross-sectional shape of the first wall portion 31 and the second wall portion 32 is circular or elliptical, the contact area between the top of the first wall portion 31 and the second wall portion 32 and the lower surface of the diffuser plate 61 can be reduced. This allows the light from the light source to be reflected even near the top of the first wall portion 31 and the second wall portion 32, further improving the uniformity of the light from the surface light source 2.

[0087] FIG. 16 is a partially enlarged cross-sectional view (part 2) illustrating a surface light source according to the second embodiment. FIG. 16 shows a cross section corresponding to FIG. 2. As in the surface light source 2A shown in FIG. 16, at least one selected from the group consisting of a wavelength conversion sheet, a prism sheet, and a polarizing sheet, which converts light from the light source 20 into light of a different wavelength, may be provided above a diffuser plate 61. Specifically, optical members such as a wavelength conversion sheet 62, a prism sheet (a first prism sheet 63 and a second prism sheet 64), and a polarizing sheet 65 may be arranged above the diffuser plate 61 at a predetermined distance or directly or indirectly on the upper surface of the diffuser plate 61. The order in which these optical members are stacked can be set as desired.

[0088] (wavelength conversion sheet 62) The wavelength conversion sheet 62 may be disposed on either the upper or lower surface of the diffusion plate 61, but is preferably disposed on the upper surface as shown in FIG. 160. The wavelength conversion sheet 62 absorbs part of the light emitted from the light source 20 and emits light of a wavelength different from the wavelength of the light emitted from the light source 20. For example, the wavelength conversion sheet 62 absorbs part of the blue light from the light source 20 and emits yellow light, green light, and / or red light, thereby realizing a surface light source 1 that emits white light. Since the wavelength conversion sheet 62 is located away from the light emitting element 21 of the light source 20, phosphors with poor resistance to heat or light intensity that are difficult to use near the light emitting element 21 can be used. This improves the performance of the surface light source 1 as a backlight. The wavelength conversion sheet 62 has a sheet or layer shape.

[0089] (First prism sheet 63 and second prism sheet 64) The first prism sheet 63 and the second prism sheet 64 have a shape in which a plurality of prisms extending in a predetermined direction are arranged on their surfaces. For example, the first prism sheet 63 can have a plurality of prisms extending in the X direction, and the second prism sheet 64 can have a plurality of prisms extending in the Y direction. The first prism sheet 63 and the second prism sheet 64 can refract light incident from various directions toward the display panel facing the surface light source 1. This allows the light emitted from the light-emitting surface of the surface light source 1 to be emitted mainly in a direction perpendicular to the upper surface, thereby increasing the brightness when the surface light source 1 is viewed from the front.

[0090] (Polarizing sheet 65) The polarizing sheet 65 selectively transmits light polarized in a direction that matches the polarization direction of a polarizing plate disposed on the backlight side of a display panel, such as a liquid crystal display panel, and reflects light polarized in a direction perpendicular to the polarization direction toward the first prism sheet 63 and the second prism sheet 64. A portion of the polarized light returning from the polarizing sheet 65 is reflected again by the first prism sheet 63, the second prism sheet 64, the wavelength conversion sheet 62, and the diffuser 61. The polarization direction of the light is changed and converted into polarized light having the polarization direction of, for example, the polarizing plate of the liquid crystal display panel. The light then re-enters the polarizing sheet 65 and is emitted to the display panel. This aligns the polarization direction of the light emitted from the surface light source 1, enabling light polarized in a direction effective for improving the brightness of the display panel to be emitted with high efficiency. The polarizing sheet 65, the first prism sheet 63, the second prism sheet 64, and the like can be commercially available optical components for backlights.

[0091] Third Embodiment The third embodiment shows an example of a liquid crystal display device (liquid crystal display device) that uses as a backlight source the surface light source 1. Instead of the surface light source 1, a surface light source 2 or a surface light source 2A may be used.

[0092] Fig. 17 is a configuration diagram illustrating a liquid crystal display device according to the third embodiment. As shown in Fig. 17, the liquid crystal display device 1000 includes, from the top, a liquid crystal panel 720, an optical sheet 710, and a surface light source 1. The surface light source 1 may include optical members such as a DBEF (reflective polarizing sheet), a BEF (brightness enhancing sheet), or a color filter above the light source 20.

[0093] The liquid crystal display device 1000 is a so-called direct type liquid crystal display device in which a surface light source 1 is stacked below a liquid crystal panel 720. The liquid crystal display device 1000 irradiates the liquid crystal panel 720 with light emitted from the surface light source 1.

[0094] From the viewpoint of reducing the thickness of the surface light source 1, the thickness of the surface light source 1 can be set to 15 mm or less. This reduces the thickness of the surface light source 1, and the liquid crystal display device 1000 can be made thinner.

[0095] The surface light source 1 is not limited to being used as a backlight for the liquid crystal display device 1000. The surface light source 1 can also be used as a backlight for televisions, tablets, smartphones, smartwatches, head-up displays, digital signage, bulletin boards, etc. The surface light source 1 can also be used as a light source for lighting, such as an emergency light or line lighting.

[0096] The above describes preferred embodiments in detail, but 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. [Explanation of symbols]

[0097] 1,2,2A surface light source 10 Substrate 11 Base material 11a Top surface 15 Covering material 18A, 18B Conductor wiring 19 Joint materials 20 light source 21 Light-emitting element 22 Sealing member 23 Light reflective film 30, 30A, 30B, 30C Partition members 30S area 31 1st wall section 32 Second wall 40 Light-reflecting resin 40A, 40B Uncured light-reflecting resin 61 Diffuser 62 Wavelength conversion sheet 63 First prism sheet 64 Second prism sheet 65 Polarizing Sheet 500 Resin dispensing device 510 nozzle 710 Optical Sheet 720 LCD panel 1000 Liquid Crystal Display Device

Claims

1. disposing a plurality of light sources on a substrate; A step of preparing a mesh-like partition member having a plurality of regions surrounded by wall portions; and adhering the partition member to the substrate with a light reflecting resin so that each of the wall portions surrounds the light source in a plan view, In the bonding step, The light reflecting resin adheres at least a portion of the side surface of the wall portion to a portion of the surface of the substrate.

2. The bonding step includes: forming the light reflecting resin at a position on the substrate where the partition member is to be disposed; The method for manufacturing a surface light source according to claim 1 , further comprising the step of: disposing the partition member on the light reflecting resin.

3. The bonding step includes: placing the partition member directly on the substrate; The method for manufacturing a surface light source according to claim 1 , further comprising the step of: injecting the light reflecting resin onto the partition member from above the substrate.

4. The bonding step includes: a step of immersing the partition member in the light reflecting resin; The method for manufacturing a surface light source according to claim 1 , further comprising the step of: placing the partition member, in which the light reflecting resin has been immersed, on the substrate.

5. In the preparing step, The method for manufacturing a surface light source according to claim 1 , wherein the partition member is manufactured by injection molding a resin.

6. The method for manufacturing a surface light source according to claim 1 , wherein the partition member is made of a light-reflective resin.

7. In the preparing step, a partition member in which, in a longitudinal cross section cut in the width direction of the wall portion, the wall portion has a maximum width portion at a position different from a lowest portion in the thickness direction, and the width of the wall portion gradually decreases from the maximum width portion toward the lowest portion; In the bonding step, The method for manufacturing a surface light source according to any one of claims 1 to 6, wherein the light-reflecting resin bonds at least a portion of the side surface of the wall portion located on the lowermost side of the widest portion to a portion of the surface of the substrate.

8. The method for manufacturing a surface light source according to claim 7 , wherein the width of the wall portion in the vertical cross section gradually decreases from the widest portion toward the top.

9. The method for manufacturing a surface light source according to claim 7 or 8, wherein the wall portion has a circular or elliptical shape in the vertical cross section.

10. The method for manufacturing a surface light source according to claim 7 , wherein the light reflecting resin covers at least the entire side surface of the wall portion located on the lowermost side of the maximum width portion.

11. The method for manufacturing a surface light source according to claim 1 , wherein the light reflecting resin widens as it moves away from the wall portion.

12. a substrate on which a plurality of light sources are arranged; a mesh-like partition member having a plurality of areas surrounded by wall portions; a light-reflecting resin that adheres the partition member to the substrate, In a plan view, each of the wall portions of the partition member surrounds the light source, The light reflecting resin is positioned between at least a portion of the side surface of the wall portion and a portion of the surface of the substrate.

13. In the vertical cross section cut in the width direction of the wall portion, the partition member has a maximum width portion at a position different from a lowest portion of the wall portion in the thickness direction, and the width of the wall portion gradually decreases from the maximum width portion toward the lowest portion, The surface light source according to claim 12 , wherein the light reflecting resin is located between at least a part of a side surface of the wall portion located on the lowermost side of the maximum width portion and a part of a surface of the substrate.

14. The surface light source according to claim 13 , wherein the width of the wall portion in the vertical cross section gradually decreases from the widest portion toward the top.

15. The surface light source according to claim 13 or 14, wherein the wall portion has a circular or elliptical shape in the longitudinal cross section.

16. The surface light source according to claim 13 , wherein the light reflecting resin covers at least the entire side surface of the wall portion located on the lowermost side of the maximum width portion.

17. The surface light source according to claim 12 , wherein the light reflecting resin widens as it moves away from the wall portion.

18. The surface light source according to claim 12 , further comprising a diffusion plate above the light source.

19. 19. The surface light source according to claim 18, further comprising at least one selected from the group consisting of a wavelength conversion sheet, a prism sheet, and a polarizing sheet, above the diffusion plate, which converts light from the light source into light of a different wavelength.

Images