Light-emitting module and planar light source

Abstract

The invention provides a light-emitting module and a planar light source capable of reducing uneven brightness. A light-emitting module provided with a plurality of light source units arranged in a first direction and a second direction orthogonal to the first direction, each of the light source units having: at least one light-emitting element; and a translucent member that covers the light-emitting element and includes a side surface of the light source unit from which light from the light-emitting element is emitted. The side surface of the (M + 1)-th light source section in the first direction and the (N + L)-th light source section in the second direction is disposed on a normal line passing through the center of the side surface of the Mth light source section in the first direction and the Nth light source section in the second direction. And a light source section between the Nth light source section in the second direction and the (N + L) th light source section (where L is a natural number of 2 or more) is not arranged on the normal line.

Description

Technical Field

[0001] Embodiments of the present invention relate to a light-emitting module and a planar light source. Background Art

[0002] A light-emitting module formed by combining a light-emitting element such as a light-emitting diode with a light guide member is widely used, for example, as a planar light source such as a backlight for a liquid crystal display. For example, Patent Document 1 discloses a backlight device including: an LED substrate provided with a reflector and a plurality of light-emitting diodes; and a diffusion plate opposed to the LED substrate.

[0003] Prior Art Documents

[0004] Patent Documents

[0005] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2019-61929 Summary of the Invention

[0006] Problems to be Solved by the Invention

[0007] An object of embodiments of the present invention is to provide a light-emitting module and a planar light source capable of reducing luminance unevenness.

[0008] Means for Solving the Problems

[0009] According to one aspect of the present invention, a light-emitting module includes a plurality of light source units arranged along a first direction and a second direction orthogonal to the first direction. Each of the light source units includes: at least one light-emitting element; and a light-transmissive member that covers the light-emitting element and includes a side surface of the light source unit from which light from the light-emitting element exits. In a plan view, a side surface of the (M + 1)-th light source unit in the first direction and the (N + L)-th light source unit in the second direction is arranged on a normal line passing through the center of the side surface of the M-th light source unit in the first direction and the N-th light source unit in the second direction, and no light source unit is arranged between the N-th light source unit and the (N + L)-th light source unit in the second direction on the normal line, where L is a natural number of 2 or more.

[0010] According to another aspect of the present invention, a light-emitting module includes: a light guide member having a first surface, a second surface opposite to the first surface, and a plurality of through holes penetrating from the first surface to the second surface; a plurality of light source units located in respective through holes and arranged in a first direction and a second direction orthogonal to the first direction; and a plurality of light adjustment members located above respective light source units and covering respective through holes. Each light source unit includes: at least one light-emitting element; and a light-transmissive member covering the light-emitting element and including a side surface of the light source unit through which light from the light-emitting element exits. In a plan view, no other light source unit is arranged on the normal line passing through the center of the side surface of any of the plurality of light source units.

[0011] Advantages of the Invention

[0012] The light-emitting module and the planar light source according to an embodiment of the present invention can reduce brightness unevenness. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic plan view of the planar light source of the present embodiment.

[0014] Figure 2 is Figure 1 a schematic cross-sectional view taken along line II-II of

[0015] Figure 3A It is a schematic cross-sectional view of the light source unit of the present embodiment.

[0016] Figure 3B It is a schematic cross-sectional view of the light source unit of another embodiment.

[0017] Figure 4 It is a view for explaining the planar light source of the present embodiment.

[0018] Figure 5 is Figure 1 a schematic plan view of part V of

[0019] Figure 6 It is a view for explaining the planar light source of the present embodiment.

[0020] Figure 7 It is a schematic plan view of the light adjustment member of the present embodiment.

[0021] Figure 8 It is a schematic plan view of a planar light source of another embodiment with the light adjustment member omitted.

[0022] Figure 9 It is a schematic plan view of a planar light source of another embodiment.

[0023] REFERENCE MARK DESCRIPTION

[0024] 10 Light source unit

[0025] 11 Light-emitting element

[0026] 16 Normal line

[0027] 20 Light guide member

[0028] 30 Translucent member

[0029] 40 Light adjustment member

[0030] 50 Wiring substrate

[0031] 61 First adhesive layer

[0032] 62 Second adhesive layer

[0033] 70 Reflective member

[0034] 80 Conductive member

[0035] 90 Insulating layer

[0036] 100 Light-emitting module

[0037] 200 Support member

[0038] 300 Planar light source. Detailed implementation manners

[0039] Hereinafter, the implementation manners will be described with reference to the drawings. Each drawing is a schematic drawing showing the implementation manners, so there are cases where the proportions, intervals, or positional relationships of the respective members are exaggerated, or a part of the member is not shown. In this specification, the arrow direction of the Z-axis is set as the upper side, and the direction on the side opposite to the arrow direction of the Z-axis is set as the lower side. Looking at the object from above is called a top view, and the top view is synonymous with a planar view. In addition, as a cross-sectional view, there are cases where only a cross-sectional view showing the cut surface is shown.

[0040] In the following description, components having substantially the same functions are denoted by common reference numerals, and the description thereof may be omitted sometimes. In addition, there are cases where terms indicating a specific direction or position (for example, "upper", "lower", and other terms including these) are used. However, these terms are used only for facilitating the understanding of the relative direction or position in the accompanying drawings being referred to. It is sufficient that the relationship of the relative direction or position indicated by terms such as "upper" and "lower" in the accompanying drawings being referred to is the same, and in the accompanying drawings other than those of the present invention, actual products, etc., the configuration may not be the same as that in the accompanying drawings being referred to. In this specification, "parallel" includes not only the case where two straight lines, sides, surfaces, etc. do not intersect even when extended, but also the case where two straight lines, sides, surfaces, etc. intersect within a range where the formed angle is within 10°. In addition, "orthogonal" means the case where two straight lines, sides, surfaces, etc. intersect within a range of 90° ± 10°, and also includes the case where although two straight lines, sides, surfaces, etc. do not intersect, they intersect when extended. In this specification, the positional relationship expressed as "upper" also includes the case of contact and the case of being located above without contact.

[0041] [Embodiment]

[0042] Refer to Figures 1 to 8 to describe the light-emitting module 100 and the planar light source 300 of the embodiment. Figure 1 is a drawing viewed from the light-emitting surface side of the planar light source 300. As Figure 1 shown, two directions parallel to the light-emitting surface of the planar light source 300 and orthogonal to each other are set as the X direction and the Y direction. The direction orthogonal to the X direction and the Y direction is set as the Z direction. In this specification, the plane parallel to the X direction and the Y direction is sometimes referred to as the XY plane. In addition, the direction inclined at an angle of 0° or more and less than 360° with respect to the X direction in the XY plane is sometimes referred to as the lateral direction, and the Z direction is referred to as the up-and-down direction.

[0043] The planar light source 300, as Figure 2 shown, includes a light-emitting module 100 and a support member 200. The light-emitting module 100 is located on the support member 200. The light-emitting module 100 includes a light guide member 20, a light source unit 10, a light-transmissive member 30, and a light adjustment member 40. A plurality of light source units 10 are arranged along a first direction and a second direction. Hereinafter, the first direction may be alternatively referred to as the Y direction, and the second direction may be alternatively referred to as the X direction for description. The light source unit 10, as Figure 3A shown, includes a light-emitting element 11 and a light-transmissive member (hereinafter, sometimes also referred to as the light source light-transmissive member 13). The light source light-transmissive member 13 covers the light-emitting element 11 and includes the side surface of the light source unit 10 from which light from the light-emitting element 11 exits.

[0044] Figure 4This is a diagram for explaining the planar light source 300 of the present embodiment and is also a diagram for explaining the light-emitting module 100 included in the planar light source 300. As Figure 4 shown, in a plan view, on the normal line 16 passing through the center of the side surface of the M-th light source unit 10 in the first direction and the N-th light source unit 10 in the second direction (hereinafter sometimes referred to as the first light source unit 10L), the side surface of the (M + 1)-th light source unit 10 in the first direction and the {N + L} (where L is a natural number of 2 or more)-th light source unit 10 in the second direction (hereinafter sometimes referred to as the second light source unit 10M) is arranged, and on this normal line 16, no light source unit 10 is arranged between the first light source unit 10L and the second light source unit 10M. Herein, the second light source unit 10M is the light source unit 10 closest to the first light source unit 10L on the normal line 16.

[0045] In a plan view, no light source unit 10 is arranged between the first light source unit 10L and the second light source unit 10M on the normal line 16 passing through the center of the side surface of the first light source unit 10L, thereby being able to reduce the number of light source units 10 having the same light overlapping with the light advancing on the normal line 16 passing through the center of the side surface of the first light source unit 10L. As a result, it is easy to reduce the brightness unevenness of the light-emitting module 100. In addition, as a result, in a mode where the light source unit 10 has a plurality of light-emitting elements 11 and the plurality of light-emitting elements 11 have different peak wavelengths, and in a mode where the plurality of light-emitting elements 11 have different light-emitting colors, it is easy to reduce the color unevenness of the light-emitting module 100.

[0046] Hereinafter, each element constituting the light-emitting module 100 and the planar light source 300 will be described in detail.

[0047] (Light source unit 10)

[0048] As Figure 1 shown, the light-emitting module 100 includes a plurality of light source units 10 including a first light source 10A, a second light source 10B, a third light source 10C, a fourth light source 10D, a fifth light source 10E, a sixth light source 10F, a seventh light source 10G, an eighth light source 10H, and a ninth light source 10I.

[0049] In the light source unit 10, each of the first light source 10A, the second light source 10B, the third light source 10C, the fourth light source 10D, the fifth light source 10E, the sixth light source 10F, the seventh light source 10G, the eighth light source 10H, and the ninth light source 10I preferably includes a plurality of light-emitting elements 11. The peak wavelengths of the plurality of light-emitting elements 11 included in each light source unit 10 may be the same or different.

[0050] Each light source unit 10 preferably includes a plurality of light emitting elements 11. Each light source unit 10 preferably has a first light emitting element 111 that emits blue light and a second light emitting element 112 that emits green light. When each light source unit 10 includes only two light emitting elements 11, in addition to blue light and green light, the peak wavelengths of the light emitting elements can also be selected in combinations such as blue light and red light, ultraviolet light and blue light, ultraviolet light and green light, ultraviolet light and red light, or green light and red light. For example, when each light source unit 10 includes only three light emitting elements 11, in addition to two blue lights and one green light, and one blue light and two green lights, the peak wavelengths of the light emitting elements can also be selected in combinations of blue light, green light, and red light, and combinations of blue light, green light, and ultraviolet light. In addition, when each light source unit 10 includes three light emitting elements 11, in addition to including blue light and green light, the peak wavelengths of the light emitting elements can also be selected in combinations such as ultraviolet light, green light, and red light, ultraviolet light, blue light, and red light, and ultraviolet light, green light, and red light.

[0051] Figure 5 is Figure 1 A schematic top view of part V of the planar light source 300 of the present embodiment described in. Figure 6 is a diagram for explaining the planar light source 300 of the present embodiment, and for explaining the wiring board 50 of the light source unit 10 and the support member 200, the light transmissive member 30, the light adjustment member 40, etc. are appropriately omitted. Each light source unit 10 is as Figure 5 or Figure 6 shown, preferably has two first light emitting elements 111 and one second light emitting element 112 located between the two first light emitting elements 111. The first light emitting element 111 and the second light emitting element 112 are electrically connected in series between a pair of electrodes 12 of each light source unit 10. In the present embodiment, the first light emitting element 111, the second light emitting element 112, and the first light emitting element 111 are connected in series in this order. The first light emitting element 111 and the second light emitting element 112 are preferably connected via a connection portion 81 of the wiring board 50 of the support member 200 which is an element other than the light source unit 10. As Figure 6As shown, the first light-emitting element 111 has a first terminal 11A and a second terminal 11B. The second light-emitting element 112 has two terminals 11C. The first terminal 11A of the first light-emitting element 111 is the electrode 12 of the light source unit 10. The second terminal 11B of the first light-emitting element 111 is a terminal electrically connected to any one of the two terminals 11C of the second light-emitting element 112. The second terminal 11B of the first light-emitting element 111 is connected to one of the terminals 11C of the second light-emitting element 112 via the connection portion 81 of the wiring substrate 50. It should be noted that the first light-emitting element 111 and the second light-emitting element 112 may also be connected via the conductive material included in the light source unit 10.

[0052] As Figure 3A shown, the light source unit 10 includes a light-emitting element 11, and the light-emitting element 11 includes a semiconductor laminate. The semiconductor laminate includes, for example, a substrate such as sapphire or gallium nitride, an n-type semiconductor layer disposed on the substrate, a p-type semiconductor layer, and a light-emitting layer sandwiched between the n-type semiconductor layer and the p-type semiconductor layer. In addition, the light-emitting element 11 includes an n-side electrode electrically connected to the n-type semiconductor layer and a p-side electrode electrically connected to the p-type semiconductor layer. The n-side electrode and the p-side electrode constitute a part of the lower surface of the light-emitting element 11. And the light source unit 10 includes a pair of positive and negative electrodes 12. The pair of positive and negative electrodes 12 constitute a part of the lower surface of the light source unit 10. One of the pair of electrodes 12 is electrically connected to the p-side electrode, and the other is electrically connected to the n-side electrode. It should be noted that the light source unit 10 may not include the electrodes 12. In the case where the light source unit 10 does not include the pair of positive and negative electrodes 12, the n-side electrode and the p-side electrode of the light-emitting element 11 constitute a part of the lower surface of the light source unit 10. In addition, the light source unit 10 may not have a substrate such as sapphire or gallium nitride. Thus, it is easy to miniaturize the light source unit 10 in the vertical direction.

[0053] As the structure of the light-emitting layer, it 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 an integrated active layer group such as a multi quantum well structure (MQW). The light-emitting layer can emit visible light or ultraviolet light. The light-emitting layer can emit light from blue to red as visible light. As the semiconductor laminate including such a light-emitting layer, for example, it can include In x Al y Ga 1-x-yN (0 ≤ x, 0 ≤ y, x + y ≤ 1). The semiconductor laminate can include at least one of the above-mentioned light-emitting layers capable of emitting light. For example, the semiconductor laminate can be configured to include one or more light-emitting layers between an n-type semiconductor layer and a p-type semiconductor layer, or can be a structure formed by repeating a structure that sequentially includes an n-type semiconductor layer, a light-emitting layer, and a p-type semiconductor layer multiple times. When the semiconductor laminate includes multiple light-emitting layers, it can include light-emitting layers with different peak wavelengths or light-emitting layers with the same peak wavelength. It should be noted that there can be a deviation of, for example, several nm for light-emitting layers with the same peak wavelength. As such a combination of light-emitting layers, it can be appropriately selected. For example, when the semiconductor laminate includes two light-emitting layers, the light-emitting layers can be selected in 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. In addition, the light-emitting layer can include multiple active layers with different peak wavelengths or multiple active layers with the same peak wavelength.

[0054] As Figure 3A shown in the figure, the light source unit 10 includes a light source light-transmissive member 13. The light source light-transmissive member 13 covers the upper surface and the side surface of the light-emitting element 11. The light-emitting element 11 can be protected by the light source light-transmissive member 13. The light source light-transmissive member 13 can also be arranged in such a way that a part of the upper surface of the light-emitting element 11 is exposed. Thus, it is easy to miniaturize the light source unit 10 in the vertical direction.

[0055] The side surface of the light source light-transmissive member 13 is the side surface of the light source unit 10. The light emitted from the light-emitting element 11 mainly exits from the side surface of the light source light-transmissive member 13. In a cross-section, the side surface of the light source light-transmissive member 13 can be parallel to the Z direction or can be inclined with respect to the Z direction. When the side surface of the light source light-transmissive member 13 is inclined with respect to the Z direction in a cross-section, it can be inclined in such a way that the lateral length of the light source light-transmissive member 13 in the cross-section becomes longer as it approaches the lower direction, or can be inclined in such a way that it becomes shorter as it approaches the lower direction. In addition, the pair of side surfaces of the light source light-transmissive member 13 in the cross-section can also be inclined with respect to the Z direction at the same angle. In a cross-section, the side surface of the light source light-transmissive member 13 can also have steps.

[0056] For example, the light source light-transmissive member 13 has light transmissibility for the light emitted by the light-emitting element 11. The light source light-transmissive member 13 includes a light-transmissive resin and can also include a wavelength conversion substance. As the wavelength conversion substance, for example, a phosphor can be cited. As the light-transmissive resin, for example, a silicone resin or an epoxy resin can be used. In addition, as the phosphor, a yttrium-aluminum-garnet-based phosphor (for example, (Y, Gd)3(Al, Ga)5O 12: Ce), lutetium-aluminum-garnet-based phosphor (e.g., Lu3(Al,Ga)5O 12 : Ce), terbium-aluminum-garnet-based phosphor (e.g., Tb3(Al,Ga)5O 12 : Ce), CCA-based phosphor (e.g., Ca 10 (PO4)6Cl2:Eu), SAE-based phosphor (e.g., Sr4Al 14 O 25 : Eu), chlorosilicate-based phosphor (e.g., Ca8MgSi4O 16 Cl2:Eu), silicate-based phosphor (e.g., (Ba,Sr,Ca,Mg)2SiO4:Eu), β-sialon-based phosphor (e.g., (Si,Al)3(O,N)4:Eu) or α-sialon-based phosphor (e.g., Ca(Si,Al) 12 (O,N) 16 : Eu) and other oxynitride-based phosphors, LSN-based phosphors (e.g., (La,Y)3Si6N 11 : Ce), BSESN-based phosphors (e.g., (Ba,Sr)2Si5N8:Eu), SLA-based phosphors (e.g., SrLiAl3N4:Eu), CASN-based phosphors (e.g., CaAlSiN3:Eu) or SCASN-based phosphors (e.g., (Sr,Ca)AlSiN3:Eu) and other nitride-based phosphors, KSF-based phosphors (e.g., K2SiF6:Mn), KSAF-based phosphors (e.g., K2(Si 1-x Al x )F 6-x : Mn, where x satisfies 0 < x < 1.), or MGF-based phosphors (e.g., 3.5MgO-0.5MgF2-GeO2:Mn) and other fluoride-based phosphors, perovskite-structured quantum dots (e.g., (Cs,FA,MA)(Pb,Sn)(F,Cl,Br,I)3, where FA and MA represent formamidine and methylammonium, respectively), II-VI group quantum dots (e.g., CdSe), III-V group quantum dots (e.g., InP), or chalcopyrite-structured quantum dots (e.g., (Ag,Cu)(In,Ga)(S,Se)2), etc. As the phosphor added to the light source light-transmitting member 13, one type of phosphor or multiple types of phosphors can be used.

[0057] In addition, when the light source unit 10 includes a first light-emitting element 111 that emits blue light and a second light-emitting element 112 that emits green light, by including a phosphor that emits red light in the light source light-transmitting member 13, a light-emitting module 100 that emits white light can be formed. Also, by including a phosphor that emits red light and a phosphor that emits green light, a light-emitting module 100 that emits white light can be formed. Here, as a specific example, as the phosphor that emits red light, a KSF-based phosphor (e.g., K2SiF6:Mn) can be cited, and as the phosphor that emits green light, a β-sialon-based phosphor (e.g., (Si,Al)3(O,N)4:Eu) can be cited.

[0058] In addition, a wavelength conversion sheet containing the above-described phosphor can be disposed on the upper side of the planar light source 300. The wavelength conversion sheet absorbs a part of the blue light from the light source unit 10 and emits yellow light, green light, and / or red light, and a planar light source that emits white light can be formed. For example, a white light can be obtained by combining a light source unit 10 that can emit blue light with a wavelength conversion sheet containing a phosphor that can emit yellow light. In addition, a light source unit 10 that can emit blue light can be combined with a wavelength conversion sheet containing a red phosphor and a green phosphor. In addition, a light source unit 10 that can emit blue light can be combined with a plurality of wavelength conversion sheets. As the plurality of wavelength conversion sheets, for example, a wavelength conversion sheet containing a phosphor that can emit red light and a wavelength conversion sheet containing a phosphor that can emit green light can be selected. In addition, a light source unit 10 having a light-emitting element 11 that can emit blue light and a light source light-transmitting member 13 containing a phosphor that can emit red light can be combined with a wavelength conversion sheet containing a phosphor that can emit green light.

[0059] As the phosphor that can emit yellow light for the wavelength conversion sheet, for example, it is preferably to use the above-described yttrium-aluminum-garnet-based phosphor. In addition, as the phosphor that can emit green light for the wavelength conversion sheet, it is preferably to use, for example, the above-described quantum dots having a perovskite structure, III-V group quantum dots, or quantum dots having a chalcopyrite structure with a relatively narrow full width at half maximum of the emission peak wavelength. In addition, as the phosphor that can emit red light for the wavelength conversion sheet, similar to the phosphor that can emit green light, it is preferably to use, for example, the above-described KSF-based phosphor, KSAF-based phosphor, III-V group quantum dots, or quantum dots having a chalcopyrite structure with a relatively narrow full width at half maximum of the emission peak wavelength.

[0060] Alternatively, a band-pass filter that transmits light in a specific wavelength region and reflects light in other wavelength regions may be disposed between the wavelength conversion sheet and the light source unit 10. As the band-pass filter, for example, a dichroic sheet is used. The band-pass filter preferably transmits only blue light and reflects light of other colors (green light and red light). Thereby, only blue light in the light from the light source unit 10 can be incident on the wavelength conversion sheet. Therefore, by combining with the wavelength conversion sheet that absorbs a part of the blue light from the light source unit 10 and emits white light, white light can be easily emitted from the wavelength conversion sheet. In addition, the situation where light other than blue light (for example, green light, red light, etc.) that passes through the band-pass filter and is reflected by the wavelength conversion sheet returns to the light source unit 10 side can be reduced. Thereby, the brightness unevenness of the light-emitting module 100 is alleviated.

[0061] Alternatively, a diffusion sheet may be disposed between the band-pass filter and the light source unit 10. The diffusion sheet can transmit the light from the light source unit 10 and diffuse the transmitted light when the light is emitted from the diffusion sheet toward the band-pass filter side. Thereby, the brightness unevenness of the light-emitting module 100 can be reduced. The diffusion sheet faces the first surface 201 of the light guide member 20, the light-transmissive member 30, and the upper surface of the light adjustment member 40. The diffusion sheet may be in contact with or separated from the first surface 201 of the light guide member 20, the light-transmissive member 30, and / or the upper surface of the light adjustment member 40. The diffusion sheet is preferably made of a material with less absorption of the light emitted by the light-emitting element 11. As the diffusion sheet, for example, polycarbonate, polystyrene, acrylic, polyethylene, etc. can be cited. The diffusion sheet may include minute irregularities on the emission surface or may include an optical film having light diffusion properties. The diffusion sheet may be composed of a single layer or may be composed of a laminate of multiple layers.

[0062] Alternatively, a prism sheet may be disposed so as to face the side of the wavelength conversion sheet opposite to the light source unit 10. A plurality of prisms extending in one direction are arranged on the surface of the prism sheet. One prism sheet may be used for the prism sheet, or a plurality of prism sheets may be used in an overlapping manner. In the case of using a plurality of prism sheets in an overlapping manner, for example, one of the plurality can be a prism extending in the X direction, and the other can be a prism extending in the Y direction. Thereby, the light emitted from the prism sheet can be made to travel along a direction orthogonal to the emission surface of the prism sheet, and the brightness of the light-emitting module 100 in a plan view can be increased.

[0063] The light source unit 10 may further include a covering member (sometimes also referred to as the light source covering member 14). The light source covering member 14 is disposed on the lower surface of the light-emitting element 11. The light source covering member 14 is disposed such that the lower surface of the electrode 12 of the light source unit 10 is exposed from the light source covering member 14. The light source covering member 14 is also disposed on the lower surface of the light source light-transmissive member 13 that covers the side surface of the light-emitting element 11.

[0064] The light source covering member 14 has reflectivity for the light emitted by the light-emitting element 11. As the light source covering member 14, for example, a resin member including a gas such as nitrogen and / or oxygen, or a resin member including light-scattering particles can be used. As the resin member of the light source covering member 14, for example, a thermoplastic resin such as acrylic resin, polycarbonate resin, cyclic olefin resin, polyethylene terephthalate resin, or polyester resin; a thermosetting resin such as epoxy resin or silicone resin can be used. As the light-scattering particles of the light source covering member 14, for example, particles of titanium dioxide, silicon dioxide, aluminum oxide, zinc oxide, magnesium oxide, zirconium oxide, yttrium oxide, calcium fluoride, magnesium fluoride, niobium pentoxide, barium titanate, tantalum pentoxide, barium sulfate, or glass can be used. The light source covering member 14 may also include both a gas and light-scattering particles.

[0065] As Figure 3A shown, the light source unit 10 can include a light adjustment member (hereinafter, sometimes also referred to as the light source light adjustment member 15). The light source light adjustment member 15 constitutes at least a part of the upper surface of the light source unit 10. The light source light adjustment member 15 is located above the light-emitting element 11. In a plan view, the light source light adjustment member 15 overlaps with the light-emitting element 11, and at the overlapping portion, the light source light adjustment member 15 is located above the light-emitting element 11. The light source light adjustment member 15 is located above the light source light-transmissive member 13 and adjusts the amount and / or the emission direction of the light emitted from the upper surface of the light source light-transmissive member 13. The light source light adjustment member 15 has reflectivity and light-transmissivity for the light emitted by the light-emitting element 11. A part of the light emitted from the upper surface of the light source light-transmissive member 13 is reflected by the light source light adjustment member 15, and the other part passes through the light source light adjustment member 15. The transmittance of the light source light adjustment member 15 for the peak wavelength of the light-emitting element 11 is, for example, preferably 1% or more and 50% or less, more preferably 3% or more and 30% or less. By including the light source light adjustment member 15 in the light source unit 10, it is possible to reduce the situation where the area directly above the light source unit 10 is overly bright. As a result, the brightness unevenness of the light-emitting module 100 is reduced.

[0066] The light source light adjustment member 15 can be constituted by, for example, a resin member including light-scattering particles. As the resin member of the light source light adjustment member 15, the same material as the resin member of the light source covering member 14 can be used. As the light-scattering particles of the light source light adjustment member 15, the same material as the light-scattering particles of the light source covering member 14 can be used. In addition, the light source light adjustment member 15 can also be, for example, a metal member such as aluminum or silver, or a dielectric multilayer film.

[0067] As Figure 3BAs shown, the light source unit 10 may not include the light source light adjustment member 15. Thus, compared with the case where the light source unit 10 includes the light source light adjustment member 15 located above the light emitting element 11, it is easier to miniaturize the light source unit 10 in the vertical direction. As another mode of the light source unit 10, the light source unit 10 may not include the light source covering member 14. For example, the lower surface of the light source unit may be constituted by the lower surface of the light emitting element, the lower surface of the pair of electrodes 12, and the lower surface of the light source light transmissive member. As another mode of the light source unit 10, the light source unit 10 may be only the single light emitting element 11. As another mode of the light source unit 10, the light source unit 10 may not include the light source covering member 14 and the light source light transmissive member 13, and the light source light adjustment member 15 may be disposed on the upper surface of the light emitting element 11. As another mode of the light source unit 10, the light source unit 10 may not include the light source light transmissive member 13, the light source light adjustment member 15 may be disposed on the upper surface of the light emitting element 11, and the light source covering member 14 may be disposed on the lower surface of the light emitting element 11.

[0068] The shape of the light source unit 10 in a plan view is not particularly limited. The shape of the light source unit 10 in a plan view is preferably a quadrilateral.

[0069] As Figure 1 shown, a plurality of light source units 10 are preferably arranged in a dot matrix pattern at regular intervals in the X direction and the Y direction. The first light source 10A, the second light source 10B, and the third light source 10C are arranged in sequence in the X direction. The fourth light source 10D, the fifth light source 10E, and the sixth light source 10F are arranged in sequence in the X direction. The seventh light source 10G, the eighth light source 10H, and the ninth light source 10I are arranged in sequence in the X direction. In addition, the first light source 10A, the fourth light source 10D, and the seventh light source 10G are arranged in sequence in the Y direction. The second light source 10B, the fifth light source 10E, and the eighth light source 10H are arranged in sequence in the Y direction. The third light source 10C, the sixth light source 10F, and the ninth light source 10I are arranged in sequence in the Y direction. It should be noted that as long as the plurality of light source units 10 are arranged in the X direction and the Y direction, they may not be arranged in a dot matrix pattern.

[0070] Each light source unit 10 as Figure 6As shown in the figure, when viewed from above, there are a plurality of normal lines 16 passing through the center of the side surface of the light source unit 10. Here, the light source unit 10 includes, for example, two first light-emitting elements 111 that emit blue light, and a second light-emitting element 112 that emits green light is included between the two first light-emitting elements 111. In addition, when viewed from above, the light source unit 10 has a quadrilateral shape with four side surfaces. When viewed from above, each of the three light-emitting elements 11 has a rectangular shape composed of four side surfaces. And the three light-emitting elements 11 are arranged such that the side surfaces on the long side of each are parallel to the side surface of the light source unit 10, and the side surfaces on the short side of each are parallel to the other side surface of the light source unit 10. The normal line 16 that intersects only the second light-emitting element 112 among the first light-emitting element 111 and the second light-emitting element 112 is called the first normal line 161. The normal line 16 that intersects both the first light-emitting element 111 and the second light-emitting element 112 is called the second normal line 162. As Figure 4 As shown in the figure, when viewed from above, the side surface of the sixth light source 10F is arranged on the first normal line 161 passing through the center of the side surface of the first light source 10A, and on the first normal line 161, no light source unit 10 is arranged between the first light source 10A and the sixth light source 10F. Similarly, the side surface of the ninth light source 10I is arranged on the first normal line 161 passing through the center of the side surface of the fourth light source 10D, and on the first normal line 161, no light source unit 10 is arranged between the fourth light source 10D and the ninth light source 10I. In addition, when viewed from above, the side surface of the second light source 10B is arranged on the second normal line 162 passing through the center of the side surface of the seventh light source 10G, and on the second normal line 162, no light source unit is arranged between the seventh light source 10G and the second light source 10B. Similarly, the side surface of the third light source 10C is arranged on the second normal line 162 passing through the center of the side surface of the eighth light source 10H, and on the second normal line 162, no light source unit 10 is arranged between the eighth light source 10H and the third light source 10C. It should be noted that preferably, with respect to any light source unit 10, other light source units 10 having side surfaces located on the normal line 16 are as far away from the arbitrary light source unit 10 as possible.

[0071] Therefore, when summarizing these, in the present embodiment, the plurality of light source units 10 have the following positional relationship. On the normal line 16 passing through the center of the side surface of the Mth light source unit 10 (the first light source unit 10L) in the first direction and the Nth light source unit 10 in the second direction, the side surface of the (M + 1)th light source unit 10 in the first direction and the {N + L (where L is a natural number of 2 or more)}th light source unit 10 (the second light source unit 10M) in the second direction is arranged, and on this normal line 16, no light source unit 10 is arranged between the first light source unit 10L and the second light source unit 10M. Here, in this case, the second light source unit 10M is the light source unit 10 closest to the first light source unit 10L on the corresponding normal line 16.

[0072] Here, in this specification, disposing the side surface of the light source unit 10 on the normal line 16 means that the normal line 16 intersects the side surface of the light source unit 10. For example, the normal line 16 of the M-th light source unit 10 in the first direction and the N-th light source unit 10 in the second direction may be orthogonal or inclined with respect to the side surface of the (M + 1)-th light source unit 10 in the first direction and the (N + L)-th light source unit 10 in the second direction.

[0073] In the present embodiment, in any of the cases where the normal line 16 is the first normal line 161 and the second normal line 162, the plurality of light source units 10 are in the above positional relationship. However, for example, the above positional relationship may be established only with respect to the first normal line 161, or may be established only with respect to the second normal line 162.

[0074] By setting the plurality of light source units 10 to such a positional relationship and size, on the normal line 16 of the first light source unit 10L, no light source unit 10 is disposed between the first light source unit 10L and the second light source unit 10M. Therefore, the number of light source units 10 having the same light overlapping with the light advancing on the normal line 16 passing through the center of the side surface of the first light source unit 10L can be reduced. As a result, the situation where the region on the normal line 16 passing through the center of the side surface of the first light source unit 10L is overly bright can be reduced, and it is easy to reduce the brightness unevenness of the light emitting module 100. In particular, for example, in the case of the light source unit 10 including a plurality of light emitting elements 11 that emit different colors of light, such as a first light emitting element 111 that emits blue light and a second light emitting element 112 that emits green light, the color unevenness generated by these different colors can be easily reduced.

[0075] In addition, the angle formed by the normal line 16 in the normal line 16 of the first light source unit 10L that intersects the side surface of the second light source unit 10M and the second direction is preferably 22° or more and 32° or less, more preferably 23° or more and 30° or less, and further preferably 25° or more and 29° or less. For example, the side surface of the sixth light source 10F is arranged on the first normal line 161 passing through the center of the side surface of the first light source 10A. Therefore, the angle α1 formed by the first normal line 161 passing through the center of the side surface of the first light source 10A and the X direction as the second direction is preferably within the above range. For example, the side surface of the second light source 10B is arranged on the second normal line 162 passing through the center of the side surface of the seventh light source 10G. Therefore, the angle α2 formed by the second normal line 162 passing through the center of the side surface of the seventh light source 10G and the Y direction as the second direction is preferably within the above range. Thereby, the number of light source units having the same light overlapping with the light advancing on the normal line 16 passing through the center of the side surface of the first light source unit 10L can be reduced. Thereby, it is possible to reduce the situation where the region arranged on the normal line 16 passing through the center of the side surface of the light source unit 10 is excessively bright, and it is easy to reduce the brightness unevenness of the light emitting module 100. In particular, in the case of a light source unit including a plurality of light emitting elements that emit light of different colors, color unevenness is easily reduced.

[0076] It should be noted that in the present embodiment, the light source unit 10 is preferably a rectangle or a square with a side length of 0.5 mm or more and 2 mm or less in plan view. As a specific example, a square with a side length of 1 mm can be cited. In addition, the light emitting element 11 included in the light source unit 10 is preferably a rectangle in plan view, preferably having a long side of 400 μm or more and 1000 μm or less, and a short side of 100 μm or more and 600 μm or less. As a specific example, a rectangle with a long side of 600 μm and a short side of 200 μm can be cited.

[0077] In addition, in the present embodiment, among the plurality of light source units 10 arranged in a matrix pattern, the distance between adjacent light source units 10 in the first direction and the second direction (the length of the line segment connecting the centers of the light source units 10) is preferably set to 4 mm or more and 13 mm or less, and is set to 8 mm as a specific example. It should be noted that when the light guide member 20 described later has the dividing groove 20Y, the shape of one region divided by the dividing groove 20Y in plan view is a rectangle or a square, and the size of one region divided by the dividing groove 20Y is preferably set to 4 mm or more and 13 mm or less in the first direction and the second direction, and is set to 8 mm as a specific example.

[0078] In a top view, the first light-emitting element 111, the second light-emitting element 112, and the direction in which the first light-emitting element 111 is arranged (i.e., the direction along the second normal line 162) can be parallel in all of the plurality of light source units 10, or can be arranged to be rotated 90° with respect to adjacent light source units 10.

[0079] (Light guide member 20)

[0080] The light guide member 20 is a member having translucency for the light emitted from the light source unit 10. The transmittance of the light guide member 20 for the peak wavelength of the light source unit 10 is preferably 60% or more, more preferably 80% or more. As shown in FIG. 3, it has a first surface 201 that becomes the light-emitting surface of the light-emitting module 100 and a second surface 202 located on the opposite side of the first surface 201. The light guide member 20 has a through hole 20X that penetrates from the first surface 201 to the second surface 202. The light source unit 10 is arranged in the through hole 20X of the light guide member 20 as Figure 1 shown. Thus, the light guide member 20 surrounds the light source unit 10 in a top view. The through hole 20X in the present embodiment is circular in a top view. The through hole 20X may be elliptical, triangular, quadrilateral, hexagonal, octagonal or other polygonal shapes in a top view.

[0081] In a cross-sectional view, the lateral length of the through hole 20X may be the same from the first surface 201 to the second surface 202, or may be different between the upper side and the lower side. When the lateral length of the through hole 20X is different between the upper side and the lower side in a cross-sectional view, the side surface of the through hole 20X may be inclined with respect to the Z direction, or may have a step including a surface parallel to the XY plane.

[0082] The number of light guide members 20 included in the light-emitting module 100 may be one or more. In the present embodiment, the light-emitting module 100 includes a plurality of light guide members 20 including a first light guide portion 20A, a second light guide portion 20B, a third light guide portion 20C, a fourth light guide portion 20D, a fifth light guide portion 20E, a sixth light guide portion 20F, a seventh light guide portion 20G, an eighth light guide portion 20H, and a ninth light guide portion 20I. As Figure 1 shown, in the X direction, the first light guide portion 20A, the second light guide portion 20B, and the third light guide portion 20C are arranged in sequence. In the X direction, the fourth light guide portion 20D, the fifth light guide portion 20E, and the sixth light guide portion 20F are arranged in sequence. In the X direction, the seventh light guide portion 20G, the eighth light guide portion 20H, and the ninth light guide portion 20I are arranged in sequence. In the Y direction, the first light guide portion 20A, the fourth light guide portion 20D, and the seventh light guide portion G are arranged in sequence. In the Y direction, the second light guide portion 20B, the fifth light guide portion 20E, and the eighth light guide portion H are arranged in sequence. In the Y direction, the third light guide portion 20C, the sixth light guide portion 20F, and the ninth light guide portion I are arranged in sequence.

[0083] The first light source 10A is located in the through hole 20X of the first light guide part 20A. The second light source 10B is located in the through hole 20X of the second light guide part 20B. The third light source 10C is located in the through hole 20X of the third light guide part 20C. The fourth light source 10D is located in the through hole 20X of the fourth light guide part 20D. The fifth light source 10E is located in the through hole 20X of the fifth light guide part 20E. The sixth light source 10F is located in the through hole 20X of the sixth light guide part 20F. The seventh light source 10G is located in the through hole 20X of the seventh light guide part 20G. The eighth light source 10H is located in the through hole 20X of the eighth light guide part 20H. The ninth light source 10I is located in the through hole 20X of the ninth light guide part 20I.

[0084] The light guide member 20 is divided by the dividing groove 20Y. It may not have the dividing groove 20Y. By having the dividing groove 20Y, the contrast between the light-emitting area in the light-emitting state and the light-emitting area in the non-light-emitting state can be improved. One area divided by the dividing groove 20Y is set as the light-emitting area 300A. In the present embodiment, the first light guide part 20A, the second light guide part 20B, the third light guide part 20C, the fourth light guide part 20D, the fifth light guide part 20E, the sixth light guide part 20F, the seventh light guide part 20G, the eighth light guide part 20H, and the ninth light guide part 20I divided by the dividing groove 20Y are respectively different light-emitting areas 300A. One light-emitting area 300A can be used as a driving unit for local dimming. The number of the light-emitting areas 300A constituting the planar light source 300 is not particularly limited. For example, the planar light source 300 may have one light-emitting area 300A, or the planar light source 300 may have a plurality of light-emitting areas 300A. In addition, a larger planar light source device can be formed by arranging a plurality of planar light sources 300. A member having reflectivity to the light emitted from the light source unit 10 may be disposed in the dividing groove 20Y. It should be noted that the light-emitting module may not dispose a member having reflectivity to the light emitted from the light source unit 10 in the dividing groove 20Y.

[0085] In the present embodiment, the light guide member 20 may have a lattice-shaped dividing groove 20Y composed of a first dividing groove 21Y extending in the Y direction and a second dividing groove 22Y extending in the X direction.

[0086] The side surface of the dividing groove 20Y may be a surface parallel to the Z direction, or may be a surface inclined with respect to the Z direction. When the side surface of the dividing groove 20Y is a surface inclined with respect to the Z direction, the opposing side surfaces in the dividing groove 20Y may have a shorter opposing distance as they tend downward, or may have a longer opposing distance as they tend downward.

[0087] As Figure 1As shown, the light guide member 20 preferably has a light guide hole portion 21 that opens on the first surface 201 and / or the second surface 202 of the light guide member 20. In a plan view, the light guide hole portion 21 is located between the through hole 20X and the dividing groove 20Y. In the present embodiment, the light guide hole portion 21 is a concave portion that opens only on the side of the first surface 201. The light guide hole portion 21 may also be a concave portion that opens only on the side of the second surface 202, or may be a through hole that penetrates from the first surface 201 to the second surface 202 of the light guide member 20. By including the light guide hole portion 21 in the light guide member 20, the surface area of the light guide member 20 can be increased. Thereby, the amount of light guided out from the surface of the light guide member 20 to the outside of the light guide member 20 can be increased. Thereby, the light extraction efficiency of the light emitting module 100 can be improved. In a plan view, the light guide hole portion 21 is preferably arranged away from the light source portion. Thereby, it is possible to reduce the situation where the area directly above the light source portion 10 is overly bright.

[0088] The light guide member 20 may include one light guide hole portion 21 or may include a plurality of light guide hole portions 21. As Figure 1 shown, preferably, in a plan view, the plurality of light guide hole portions 21 surround the light source portion 10. Thereby, it is easy to guide the light advancing laterally from the light source portion 10 to the outside of the light guide member 20 by the plurality of light guide hole portions 21. In addition, by surrounding the light source portion 10 with the plurality of light guide hole portions 21 in a plan view, it is easy to mix a portion with a higher brightness and a portion with a lower brightness near the light guide hole portion 21. Thereby, it is possible to prevent the boundary between the brightness of the portion located inside the outer edge of the light guide hole portion 21 and the brightness of the portion located outside the outer edge of the light guide hole portion 21 from being significant in a plan view. It should be noted that, in a plan view, one light guide hole portion 21 may surround the light source portion 10 without a gap.

[0089] The shape of the light guide hole portion 21 in a plan view is not particularly limited. As Figure 1 shown, the shape of the light guide hole portion 21 in the present embodiment includes a linear portion. In this specification, the linear shape also includes a straight line, a curve, or a bent line, etc. The shape of the light guide hole portion 21 in a plan view may also be a V-shape or an L-shape extending in two directions. In addition, the shape of the light guide hole portion 21 in a plan view may also be a circle, an ellipse, or a polygon such as a triangle, a quadrilateral, a hexagon, or an octagon.

[0090] In this specification, as Figure 1As shown in the figure, the point farthest from the center of the first light source 10A among the outer edges of the first light guide portion 20A on the first surface 201 is referred to as the first point P1, and the point closest to the center of the first light source 10A among the outer edges of the first light guide portion 20A on the first surface 201 is referred to as the second point P2. In the present embodiment, the first point P1 is located at each corner of the first light guide portion 20A, and the second point P2 is located at the center of each side of the first light guide portion 20A. The first point P1 and the second point P2 may each be one or a plurality of points.

[0091] Preferably, in a plan view, at least one of the light guide hole portions 21 is located on a first imaginary straight line IL connecting the center of the first light source 10A and the first point P1. Thereby, the brightness unevenness of the light emitting module 100 is reduced. The first point P1 far from the first light source 10A is more likely to have a lower brightness than the second point P2 close to the first light source 10A. However, by arranging the light guide hole portion 21 on the first imaginary straight line IL, it is easy to increase the amount of light guided from the light guide member 20 to the outside near the first point P1. Thereby, the difference in brightness between the first point P1 and the second point P2 can be reduced, and thus the brightness unevenness of the light emitting module 100 is reduced.

[0092] In addition, preferably, a plurality of light guide hole portions 21 are located on the first imaginary straight line IL connecting the center of the first light source 10A and the first point P1. Thereby, it becomes easy to adjust the brightness near the first point P1, and thus it is easy to reduce the brightness unevenness of the light emitting module 100. The number of light guide hole portions 21 located on the first imaginary straight line IL is preferably larger than the number of light guide hole portions 21 located on a second imaginary straight line IIL connecting the center of the first light source 10A and the second point P2. Thereby, it is easy to reduce the difference in brightness between the first point P1 and the second point P2. There may be no light guide hole portion 21 located on the second imaginary straight line IIL.

[0093] Preferably, in a plan view, at least one of the light guide hole portions 21 extends obliquely away from the first light source 10A with respect to the X direction and the Y direction from the end of the light guide hole portion 21 close to the center of the first light source 10A. Thereby, a part of the light from the first light source 10A can be guided in the direction in which the light guide hole portion 21 extends. Thereby, the brightness unevenness of the light emitting module 100 can be reduced.

[0094] As the material of the light guide member 20, the same material as the resin member of the light source covering member 14 can be used. In addition, as the material of the light guide member 20, glass or the like can also be used. The light guide member 20 may also include a phosphor and / or light scattering particles.

[0095] The thickness of the light guide member 20 is preferably, for example, 150 μm or more and 800 μm or less. In this specification, unless otherwise specified, the thickness of each member is set to the value when the distance from the upper surface to the lower surface of each member in the up-down direction is the maximum. The light guide member 20 may be composed of a single layer in the up-down direction or may be composed of a laminate of multiple layers. When the light guide member 20 is composed of a laminate, a light-transmissive adhesive may be disposed between the layers. The main materials of the respective layers of the laminate may also be of different types.

[0096] The method of forming the light guide hole portion 21 in the light guide member 20 is not particularly limited. For example, the light guide hole portion 21 can be formed in the light guide member 20 by laser processing. The light guide hole portion 21 can be formed using the heat generated by laser irradiation. It should be noted that the light guide member including the light guide hole portion 21 can also be formed by methods such as injection molding, transfer molding, and compression molding using a mold or the like.

[0097] (Light-transmissive member 30)

[0098] As Figure 2 shown, the light-emitting module 100 includes a light-transmissive member 30. The light-transmissive member 30 is a member having light transmissivity with respect to the light emitted from the light source unit 10. The light-transmissive member 30 has a first light-transmissive portion 31 and a second light-transmissive portion 32. In the present embodiment, the first light-transmissive portion 31 and the second light-transmissive portion 32 are separate. The first light-transmissive portion 31 and the second light-transmissive portion 32 may also be integrally formed of the same material. The transmittance of each of the first light-transmissive portion 31 and the second light-transmissive portion 32 with respect to the peak wavelength of the light source unit 10 is preferably, for example, 60% or more, and more preferably 80% or more. It should be noted that the light-emitting module 100 may not include the light-transmissive member 30.

[0099] As Figure 2 shown, the first light-transmissive portion 31 preferably contacts the side surface of the light source unit 10. Thereby, the light from the light source unit 10 easily enters the first light-transmissive portion 31. The first light-transmissive portion 31 preferably contacts the light guide member 20. Thereby, the light from the light source unit 10 easily enters the light guide member 20. When the light-emitting module 100 does not include the light-transmissive member 30, the light guide member 20 may also contact the side surface of the light source unit 10. Thereby, the light from the light source unit 10 easily enters the light guide member 20.

[0100] The first light-transmitting part 31 is preferably arranged in such a way as to expose at least a part of the upper surface of the light source part 10. Thus, compared with the case where the first light-transmitting part 31 covers the entire upper surface of the light source part 10, it is easier to miniaturize the light-emitting module 100 in the vertical direction. The first light-transmitting part 31 may also be arranged in such a way as to expose the entire upper surface of the light source part 10. In addition, the first light-transmitting part 31 may also cover the entire upper surface of the light source part 10. By covering the entire upper surface of the light source part 10 with the first light-transmitting part 31, it becomes easier to adjust the brightness in the region directly above the light source part 10. For example, by changing the thickness of the first light-transmitting part 31 that covers the upper surface of the light source part 10, the brightness in the region directly above the light source part 10 can be adjusted. Thus, the adjustment of the brightness becomes easier, and it is easier to reduce the brightness unevenness of the light-emitting module 100. When the first light-transmitting part 31 covers the upper surface of the light source part 10, the second light-transmitting part 32 covers the upper surface of the light source part 10 via the first light-transmitting part 31.

[0101] The first light-transmitting part 31 may be composed of a single layer in the vertical direction or may be composed of a laminate of multiple layers. In addition, the first light-transmitting part 31 may also include a phosphor, which is a wavelength conversion substance, and light-scattering particles. When the first light-transmitting part 31 is a laminate, each layer may include a phosphor and / or light-scattering particles, or may not include them. For example, the first light-transmitting part 31 may be composed of a layer including a phosphor and a layer not including a phosphor. As the material of the first light-transmitting part 31, for example, the same material as the resin member of the light source covering member 14 can be used.

[0102] The second light-transmitting part 32 is located above the light source part 10. The second light-transmitting part 32 is located above the first light-transmitting part 31. The second light-transmitting part 32 is preferably in contact with the upper surface of the light source part 10 and / or the upper surface of the first light-transmitting part 31. Thus, it is easier to miniaturize the light-emitting module 100 in the vertical direction.

[0103] As the material of the second light-transmitting part 32, for example, the same material as the resin member of the covering member 14 can be used. In addition, as the second light-transmitting part 32, a sheet-like optical transparent adhesive (OCA) can also be used. The second light-transmitting part 32 may also include a phosphor, which is a wavelength conversion substance, and light-scattering particles.

[0104] (Light adjustment member 40)

[0105] The light adjustment member 40 has reflectivity and light transmittance to the light emitted by the light source unit 10. A portion of the light emitted from the light source unit 10 is reflected by the light adjustment member 40, and the other portion is transmitted through the light adjustment member 40. The transmittance of the peak wavelength of the light source unit 10 by the light adjustment member 40 is lower than the transmittance of the peak wavelength of the light source unit 10 by the light guide member 20. For example, the transmittance of the peak wavelength of the light source unit 10 by the light adjustment member 40 is preferably 1% or more and 50% or less, and more preferably 3% or more and 30% or less. The light adjustment member 40 may be composed of a single layer or a laminate of a plurality of layers.

[0106] The light adjustment member 40 is disposed on the upper side of the light source unit 10. The light adjustment member 40 overlaps with the light source unit 10 in a plan view, and the light adjustment member 40 is located on the upper side of the light source unit 10 in the overlapping portion. By locating the light adjustment member 40 on the upper side of the light source unit 10, it is possible to reduce the situation where the area directly above the light source unit 10 is excessively bright.

[0107] The light adjustment member 40 is disposed on the upper side of the first light-transmitting portion 31. In a plan view, the light adjustment member 40 overlaps with the first light-transmitting portion 31, and the light adjustment member 40 is located on the upper side of the first light-transmitting portion 31 at the overlapping portion. By locating the light adjustment member 40 on the upper side of the first light-transmitting portion 31, it is possible to reduce the situation where the area directly above the first light-transmitting portion 31 is too bright.

[0108] The light adjustment member 40 is disposed on the upper side of the second light-transmitting portion 32. In a plan view, the light adjustment member 40 overlaps with the second light-transmitting portion 32, and in the overlapping portion, the light adjustment member 40 is located on the upper side of the second light-transmitting portion 32. By locating the light adjustment member 40 on the upper side of the second light-transmitting portion 32, it is possible to reduce the situation where the area directly above the second light-transmitting portion 32 is too bright.

[0109] like Figure 5 As shown, it is preferred that, in a plan view, at least a portion of the outer edge of the light adjustment member 40 is located at a position that is outside the outer edge of the through hole 20X. Thereby, the situation where the outer edge of the through hole 20X is too bright can be reduced. In a plan view, it is also possible that the outer edge of the light adjustment member 40 is located at a position that is outside the outer edge of the through hole 20X. Thereby, the situation where the outer edge of the through hole 20X is too bright can be further reduced. In addition, it is also possible that, in a plan view, the outer edge of the light adjustment member 40 is located at a position that is inside the outer edge of the through hole 20X. Thereby, the area of ​​the light-transmitting member 30 exposed from the light adjustment member 40 in a plan view is easily increased. Thereby, the amount of light that is led out of the light-transmitting member 30 to the outside of the light-transmitting member 30 can be increased.

[0110] The light adjustment member 40 is as follows Figure 7has a plurality of grooves (hereinafter, sometimes also referred to as light adjustment grooves 42) as shown. By having the light adjustment grooves 42, the light adjustment member 40 makes it easier to adjust the brightness in the region directly above the light adjustment member 40. The light adjustment grooves 42 preferably include a plurality of first grooves 421, a plurality of second grooves 422, a plurality of third grooves 423, a plurality of fourth grooves 424, a plurality of fifth grooves 425, and a plurality of outer peripheral grooves 426. Thereby, for example, in a light source unit 10 having a plurality of light-emitting elements 11 with different peak wavelengths, such as the light source unit 10 having a first light-emitting element 111 that emits blue light and a second light-emitting element 112 that emits green light, it is easy to reduce color unevenness.

[0111] The first groove 421 intersects, in a plan view, with an imaginary line K1 that is parallel to the direction in which the plurality of light-emitting elements are arranged and passes through the center of the light-emitting element. The length direction of each first groove 421 is preferably orthogonal to the direction in which the plurality of light-emitting elements are arranged. In this case, each first groove 421 faces each first light-emitting element 111. The maximum length in the length direction of the first groove 421 is preferably 10% or more and 100% or less, more preferably 30% or more and 90% or less, and still more preferably 40% or more and 80% or less, relative to the maximum length of the first light-emitting element 111. In addition, the minimum distance L3 between the first light-emitting element 111 and the first groove 421 is preferably 10% or more and 100% or less, more preferably 20% or more and 75% or less, and still more preferably 30% or more and 50% or less, relative to the thickness of the light source unit.

[0112] The second groove 422 intersects, in a plan view, with an imaginary line K2 that is orthogonal to the direction in which the plurality of light-emitting elements 11 are arranged and passes through the center of the second light-emitting element 112. The length direction of each second groove 422 is preferably parallel to the direction in which the plurality of light-emitting elements 11 are arranged. In this case, each second groove 422 faces each second light-emitting element 112. The maximum length in the length direction of the second groove 422 is preferably shorter than the maximum length of the first groove 421, and more preferably not more than the minimum distance between two first light-emitting elements 111. The maximum length of the second groove 422 is preferably 30% or more and 90% or less, more preferably 40% or more and 85% or less, and still more preferably 55% or more and 75% or less, relative to the maximum length in the length direction of the first groove 421.

[0113] The minimum distance L4 between the second groove 422 and the second light-emitting element 112 is preferably longer than the minimum distance between the first light-emitting element 111 and the first groove 421. The minimum distance between the second groove 422 and the second light-emitting element 112 is preferably 110% or more and 500% or less, more preferably 150% or more and 400% or less, and still more preferably 175% or more and 300% or less, relative to the minimum distance between the first light-emitting element 111 and the first groove 421.

[0114] A plurality of third grooves 423 are formed along a first imaginary circle K3. The radius of the first imaginary circle K3 is larger than the maximum distance from the center of the light source unit 10 to the second groove 422. A plurality of fourth grooves 424 are formed along a second imaginary circle K4. The radius of the second imaginary circle K4 is larger than the radius of the first imaginary circle K3. A plurality of fifth grooves 425 are formed along an octagonal imaginary line K5. The radius of the circumscribed circle of the octagonal imaginary line K5 is larger than the radius of the second imaginary circle K4. The plurality of fifth grooves 425 are formed in an L shape corresponding to the corners in the octagonal imaginary line K5, and adjacent fifth grooves 425 are separated. The plurality of fourth grooves 424 are circumferentially located between adjacent fifth grooves 425. The plurality of third grooves 423 are circumferentially located between adjacent fourth grooves 424.

[0115] An outer peripheral groove 426 is formed along the outer peripheral edge of the light adjustment member 40. The shape of the outer peripheral groove 426 in plan view is octagonal. The shape of the outer peripheral groove 426 in plan view can be, for example, a polygon such as a triangle, a quadrilateral, a hexagon, etc., in addition to an ellipse and a circle. The plurality of outer peripheral grooves 426 surround the first groove 421, the second groove 422, the third groove 423, the fourth groove 424, and the fifth groove 425. The plurality of outer peripheral grooves 426 are formed at intervals from the center to the outer peripheral edge of the light adjustment member 40.

[0116] The maximum length (maximum width) of the light adjustment groove 42 in the direction orthogonal to the length direction is preferably 0.01 mm or more and 0.2 mm or less, more preferably 0.02 mm or more and 0.08 mm or less, and further preferably 0.03 mm or more and 0.07 mm or less. In addition, the light adjustment groove 42 may not penetrate in the entire length range, or may penetrate partially.

[0117] (Support member 200)

[0118] As Figure 2 shown, the support member 200 is a member for arranging the light emitting module 100. The light guide member 20 is arranged on the support member 200 such that the second surface 202 faces the upper surface of the support member 200.

[0119] The support member 200 has a wiring board 50. The wiring board 50 has an insulating substrate 51 and at least one wiring layer 52 arranged on at least one surface of the insulating substrate 51. The insulating substrate 51 can be a rigid substrate or a flexible substrate. For the thinning of the surface light source 300, the insulating substrate 51 is preferably a flexible substrate. The insulating substrate 51 can be composed of a single layer in the up-down direction or can be a laminate of multiple layers. For example, the insulating substrate 51 can be composed of a single-layer flexible substrate or can be a laminate of multiple rigid substrates. As the material of the insulating substrate 51, for example, a resin such as polyimide can be used. The wiring layer 52 is a metal film, for example, a copper film.

[0120] The support member 200 also has a first adhesive layer 61 disposed on the wiring substrate 50, a reflection member 70 disposed on the first adhesive layer 61, and a second adhesive layer 62 disposed on the reflection member 70.

[0121] The first adhesive layer 61 is disposed between the wiring substrate 50 and the reflection member 70 and bonds the wiring substrate 50 and the reflection member 70. The first adhesive layer 61 can be formed of a resin member including light-scattering particles, for example. As the resin member of the first adhesive layer 61, the same material as the resin member of the light source covering member 14 can be used, for example. As the light-scattering particles of the first adhesive layer 61, the same material as the light-scattering particles of the light source covering member 14 can be used, for example. As the first adhesive layer 61, a sheet-like optical transparent adhesive can also be used.

[0122] The refractive index of the resin member of the first adhesive layer 61 is preferably lower than the refractive index of the resin member of the reflection member 70. Thus, a part of the light advancing from the reflection member 70 to the first adhesive layer 61 is likely to undergo total reflection at the interface between the reflection member 70 and the first adhesive layer 61. Thereby, the light leaking downward from the light-emitting module 100 can be reduced, and thus the light extraction efficiency of the light-emitting module 100 is improved.

[0123] The reflection member 70 is disposed below the light guide member 20, below the light source unit 10, and below the light-transmissive member 30. The reflection member 70 has reflectivity for the light emitted from the light source unit 10. The reflection member 70 can be formed of a resin member and a reflector contained in the resin member. As the resin member of the reflection member 70, the same material as the resin member of the light source covering member 14 can be used, for example. As the material of the reflector of the reflection member 70, the same material as the light-scattering particles of the light source covering member 14 can be used. As the reflector of the reflection member 70, gases such as nitrogen and / or oxygen can also be used. In addition, the reflection member 70 can also include both light-scattering particles and gases as the reflector.

[0124] The refractive index of the reflector of the reflection member 70 is preferably lower than the refractive index of the resin member of the reflection member 70. Thus, a part of the light from the light source unit 10 incident on the reflection member 70 is likely to undergo total reflection at the interface between the resin member of the reflection member 70 and the reflector of the reflection member 70. Thereby, the light leaking downward from the reflection member 70 can be reduced, and thus the light extraction efficiency of the light-emitting module 100 is improved.

[0125] When the refractive index of the reflector of the reflection member 70 is lower than the refractive index of the resin member of the reflection member 70, the refractive index of the resin member of the reflection member 70 is preferably higher than the refractive index of the base material of the light guide member 20. Thereby, it is easy to increase the refractive index difference between the resin member of the reflection member 70 and the reflector of the reflection member 70. Thereby, a part of the light from the light source unit 10 incident on the reflection member 70 is likely to undergo total internal reflection at the interface between the resin member of the reflection member 70 and the reflector of the reflection member 70.

[0126] The second adhesive layer 62 is disposed between the reflection member 70 and the second surface 202 of the light guide member 20 and bonds the reflection member 70 and the light guide member 20. The light source unit 10 is disposed on the second adhesive layer 62 within the through hole 20X of the light guide member 20. The second adhesive layer 62 can be formed of, for example, a resin member including light-scattering particles. As the resin member of the second adhesive layer 62, for example, the same material as the resin member of the light source covering member 14 can be used. As the light-scattering particles of the second adhesive layer 62, for example, the same material as the light-scattering particles of the light source covering member 14 can be used. As the second adhesive layer 62, a sheet-like optical transparent adhesive can also be used.

[0127] The refractive index of the resin member of the second adhesive layer 62 is preferably lower than the refractive index of the base material of the light guide member 20. Thereby, a part of the light advancing from the light guide member 20 to the second adhesive layer 62 is likely to undergo total internal reflection at the interface between the light guide member 20 and the second adhesive layer 62. Thereby, the light leaking downward from the light-emitting module 100 can be reduced, and thus the light extraction efficiency of the light-emitting module 100 is improved. The refractive index of the resin member of the second adhesive layer 62 is preferably lower than the refractive index of the base material of the light-transmitting portion 31. Thereby, a part of the light advancing from the light-transmitting portion 31 to the second adhesive layer 62 is likely to undergo total internal reflection at the interface between the light-transmitting portion 31 and the second adhesive layer 62. Thereby, the light leaking downward from the light-emitting module 100 can be reduced, and thus the light extraction efficiency of the light-emitting module 100 is improved.

[0128] The support member 200 further includes a conductive member 80. The conductive member 80 includes, for example, a resin and metal particles contained in the resin. As the resin of the conductive member 80, for example, epoxy resin or phenolic resin can be used. As the metal particles, for example, particles of copper or silver can be used.

[0129] The conductive member 80 has a connecting portion 81 and a wiring portion 82. The connecting portion 81 penetrates the second adhesive layer 62, the reflection member 70, the first adhesive layer 61, and the insulating substrate 51 in the vertical direction. The wiring portion 82 is disposed on the surface of the wiring substrate 50 on which the wiring layer 52 is disposed and is connected to the connecting portion 81. The connecting portion 81 and the wiring portion 82 can be integrally formed of the same material. A part of the wiring portion 82 is connected to the wiring layer 52.

[0130] Corresponding to a pair of positive and negative electrodes 12 of the light source unit 10, a pair of conductive members 80 are arranged separately from each other. The connection portion 81 of one conductive member 80 is connected to the positive-side electrode 12 below the light source unit 10, and the connection portion 81 of the other conductive member 80 is connected to the negative-side electrode 12 below the light source unit 10. The electrode 12 of the light source unit 10 is electrically connected to the conductive member 80 and the wiring layer 52.

[0131] The support member 200 further has an insulating layer 90. The insulating layer 90 is disposed on the lower surface of the wiring substrate 50 and covers the wiring layer 52. As the material of the insulating layer 90, for example, epoxy resin, polyurethane resin, or acrylic resin can be used.

[0132] [Another Embodiment]

[0133] Next, with reference to Figure 8 and Figure 9 an example of the light-emitting module 100 of another embodiment will be described.

[0134] As shown in Figure 8 in a plan view, other light source units 10 are not arranged on the first normal line 161 passing through the center of the side surface of any light source unit 10. In addition, in a plan view, other light source units 10 are not arranged on the second normal line 162 passing through the center of the side surface of any light source unit 10.

[0135] By setting the plurality of light source units 10 in such a positional relationship, other light source units 10 are not arranged on the normal line 16 of the light source unit 10. Therefore, it is possible to eliminate the light source units 10 having the same light overlapping with the light advancing on the normal line 16 passing through the center of the side surface of the light source unit 10. As a result, it is possible to reduce the situation where the area on the normal line 16 passing through the center of the side surface of the light source unit 10 is overly bright, and it is easy to reduce the brightness unevenness of the light-emitting module 100. In particular, in the case of the light source unit 10 including a plurality of light-emitting elements 11 that emit lights of different colors, color unevenness is easily reduced.

[0136] In addition, as shown in Figure 8As shown, the angle α1 formed by the normal line 16 of the light source unit 10 and the X direction is preferably 22° or more and 23° or less, more preferably 22.5°. In addition, the angle α2 formed by the normal line 16 of the light source unit 10 and the Y direction is preferably 22° or more and 23° or less, more preferably 22.5°. In the present embodiment, the formed angles α1 and α2 are the same. However, when the formed angles α1 and α2 are different, it is preferable that the smaller angle (the minimum angle) is within the above range. Thereby, the light source unit 10 having the same light overlapping with the light advancing on the normal line 16 passing through the center of the side surface of the light source unit 10 can be eliminated. Therefore, the situation where the region on the normal line 16 passing through the center of the side surface of the light source unit 10 is overly bright can be reduced, and it is easy to reduce the brightness unevenness of the light emitting module 100. In particular, for example, in the case of the light source unit 10 including a plurality of light emitting elements 11 that emit light of different colors, such as a first light emitting element 111 that emits blue light and a second light emitting element 112 that emits green light, it is easy to reduce the color unevenness of the light emitting module 100 caused by these different colors. It should be noted that the size of the light source unit 10, the size of the light emitting element 11 included in the light source unit 10, and the distance between the light source units 10 can be set to the same size as those described in other embodiments of this specification.

[0137] As Figure 9 shown, the light emitting module 100 preferably includes a light adjustment member 40. In this case, the light adjustment member 40 is preferably octagonal. By the light adjustment member 40 being octagonal, the outer protruding corners of the outer peripheral edge of the light adjustment member 40 can be arranged on the first normal line 161 and the second normal line 162. Thereby, compared with the case where the side of the outer peripheral edge of the light adjustment member 40 is arranged on the normal line 16, the light adjustment member 40 can be extended on the normal line 16. Thereby, in a plan view, the light adjustment member 40 can be extended corresponding to the direction in which the emission color of the light emitting element 11 is stronger, and it is easy to reduce the color unevenness of the light emitting module 100. It should be noted that arranging the outer protruding corners of the outer peripheral edge of the light adjustment member 40 on the normal line 16 means that the portion between the sides of the outer peripheral edge of the light adjustment member 40 is located on the normal line 16. The portion between the sides of the outer peripheral edge of the light adjustment member 40 may have corners or may be a curve.

[0138] This specification discloses a light emitting module and a planar light source described in the following solutions.

[0139] [Solution 1]

[0140] A light emitting module, wherein,

[0141] the light emitting module includes a plurality of light source units arranged along a first direction and a second direction orthogonal to the first direction,

[0142] Each of the light source units includes: at least one light emitting element; and a light transmissive member that covers the light emitting element and includes a side surface of the light source unit through which light from the light emitting element exits.

[0143] In a plan view, the side surface of the (M + 1)-th light source unit in the first direction and the (N + L)-th light source unit in the second direction is disposed on the normal line passing through the center of the side surface of the M-th light source unit in the first direction and the N-th light source unit in the second direction, and no light source unit is disposed between the N-th light source unit and the (N + L)-th light source unit in the second direction on the normal line, where L is a natural number of 2 or more.

[0144] [Solution 2]

[0145] A light emitting module, wherein

[0146] The light emitting module includes:

[0147] A light guide member having a first surface, a second surface opposite to the first surface, and a plurality of through holes penetrating from the first surface to the second surface;

[0148] A plurality of light source units located in respective ones of the through holes and arranged in a first direction and a second direction orthogonal to the first direction; and

[0149] A plurality of light adjusting members located above respective ones of the light source units and covering respective ones of the through holes,

[0150] Each of the light source units includes: at least one light emitting element; and a light transmissive member that covers the light emitting element and includes a side surface of the light source unit through which light from the light emitting element exits.

[0151] In a plan view, no other light source unit is disposed on the normal line passing through the center of the side surface of any of the plurality of light source units.

[0152] [Solution 3]

[0153] The light emitting module according to Solution 1 or Solution 2, wherein

[0154] The light source unit includes a plurality of the light emitting elements,

[0155] The plurality of light emitting elements include a first light emitting element that emits blue light and a second light emitting element that emits green light.

[0156] [Solution 4]

[0157] The light emitting module according to Solution 3, wherein

[0158] In the light source unit, there are two of the first light-emitting elements and one of the second light-emitting elements,

[0159] and the second light-emitting element is located between the two first light-emitting elements.

[0160] [Solution 5]

[0161] The light-emitting module according to Solution 4, wherein,

[0162] the normal line has a first normal line that intersects only the second light-emitting element among the first light-emitting element and the second light-emitting element, and a second normal line that intersects both the first light-emitting element and the second light-emitting element,

[0163] In a plan view, the side surface of the (M + 1)-th light source unit in the first direction and the (N + L)-th light source unit in the second direction is arranged on the first normal line passing through the center of the side surface of the M-th light source unit in the first direction and the N-th light source unit in the second direction.

[0164] [Solution 6]

[0165] The light-emitting module according to Solution 4, wherein,

[0166] the normal line has a first normal line that intersects only the second light-emitting element among the first light-emitting element and the second light-emitting element, and a second normal line that intersects both the first light-emitting element and the second light-emitting element,

[0167] In a plan view, the side surface of the (M + 1)-th light source unit in the first direction and the (N + L)-th light source unit in the second direction is arranged on the second normal line passing through the center of the side surface of the M-th light source unit in the first direction and the N-th light source unit in the second direction.

[0168] [Solution 7]

[0169] The light-emitting module according to Solution 3, wherein,

[0170] the first light-emitting element and the second light-emitting element in each of the light source units are connected in series.

[0171] [Solution 8]

[0172] The light-emitting module according to any one of Solutions 1 to 7, wherein,

[0173] the light-transmissive member includes a wavelength conversion substance.

[0174] [Solution 9]

[0175] The light-emitting module according to any one of Solutions 1 to 8, wherein,

[0176] When viewed from above, the angle formed by the normal line and the second direction is 22° or more and 32° or less.

[0177] [Solution 10]

[0178] The light-emitting module according to Solution 2, wherein

[0179] When viewed from above, the minimum angle among the angles formed by the normal line and the second direction is 22.5°.

[0180] [Solution 11]

[0181] A planar light source, wherein

[0182] The planar light source includes:

[0183] The light-emitting module according to any one of Solutions 1 to 10; and

[0184] A support member that arranges the light-emitting module.

[0185] As mentioned above, the embodiments of the present invention have been described with reference to specific examples. However, the present invention is not limited to these specific examples. All modes that can be implemented by making appropriate design changes by those skilled in the art based on the above embodiments of the present invention as long as they include the gist of the present invention also belong to the scope of the present invention. In addition, within the scope of the idea of the present invention, various modification examples and correction examples can be conceived by those skilled in the art, and these modification examples and correction examples also belong to the scope of the present invention.

Claims

1. A light emitting module, wherein: The light emitting module includes a plurality of light source units arranged along a first direction and a second direction orthogonal to the first direction. Each of the light source units has: at least one light emitting element; and a light-transmitting member that covers the light-emitting element and includes a side surface of the light source portion from which light from the light-emitting element is emitted, In a top view, the side surface of the (M+1)th light source unit in the first direction and the (N+L)th light source unit in the second direction are arranged on the normal passing through the center of the side surface of the Mth light source unit in the first direction and the Nth light source unit in the second direction, and the light source unit between the Nth light source unit and the (N+L)th light source unit in the second direction is not arranged on the normal surface, where L is a natural number greater than 2.

2. The light emitting module according to claim 1, wherein: The light source unit includes a plurality of light emitting elements. The plurality of light emitting elements include a first light emitting element that radiates blue light and a second light emitting element that radiates green light.

3. The light emitting module according to claim 2, wherein: The light source unit includes two of the first light emitting elements and one of the second light emitting elements. The second light emitting element is located between the two first light emitting elements.

4. The light emitting module according to claim 3, wherein: The normal line includes a first normal line intersecting only the second light emitting element of the first light emitting element and the second light emitting element, and a second normal line intersecting the first light emitting element and the second light emitting element. In a plan view, the side surfaces of the (M+1)th light source units in the first direction and the (N+L)th light source units in the second direction are arranged on the first normal line passing through the center of the side surfaces of the Mth light source units in the first direction and the Nth light source units in the second direction.

5. The light emitting module according to claim 3, wherein: The normal line includes a first normal line intersecting only the second light emitting element of the first light emitting element and the second light emitting element, and a second normal line intersecting the first light emitting element and the second light emitting element. In a plan view, the side surfaces of the (M+1)th and (N+L)th light source units in the first direction and the second direction are arranged on the second normal line passing through the center of the side surfaces of the Mth and Nth light source units in the first direction and the second direction.

6. The light emitting module according to claim 2, wherein: The first light emitting element and the second light emitting element in each of the light source units are connected in series.

7. The light emitting module according to claim 1, wherein: In a plan view, an angle formed by the normal line and the second direction is greater than or equal to 22° and less than or equal to 32°.

8. A light emitting module, wherein: The light emitting module comprises: a light guide member having a first surface, a second surface opposite to the first surface, and a plurality of through holes penetrating from the first surface to the second surface; a plurality of light source units, which are located in each of the through holes and arranged along a first direction and a second direction orthogonal to the first direction; and a plurality of light adjustment members, which are located above each of the light source parts and cover each of the through holes; Each of the light source units has: at least one light emitting element; and a light-transmitting member that covers the light-emitting element and includes a side surface of the light source portion from which light from the light-emitting element is emitted, In a plan view, no other light source unit is arranged on a normal line of any light source unit among the plurality of light source units that passes through the center of the side surface.

9. The light emitting module according to any one of claims 1, 2 and 8, wherein: The light-transmitting member includes a wavelength converting substance.

10. The light emitting module according to claim 8, wherein: In a plan view, a minimum angle between an angle formed by the normal line and the first direction and an angle formed by the normal line and the second direction is 22.5°.

11. A planar light source, wherein: The planar light source comprises: The light emitting module according to claim 1 or 8; and A supporting member is provided to configure the light emitting module.

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