JP7397349B2 - Planar light source - Google Patents

Description

Embodiments according to the present invention relate to a planar light source.

2. Description of the Related Art Light emitting modules, which are a combination of light emitting elements such as light emitting diodes and light guide plates, are widely used as planar light sources such as backlights for liquid crystal displays, for example.

Japanese Patent Application Publication No. 2020-13714

Embodiments of the present invention aim to provide a planar light source that can reduce uneven brightness.

According to one aspect of the present invention, a planar light source includes a light guide member having a plurality of light emitting parts separated by a groove, and a light source disposed in each of the plurality of light emitting parts, and a light guide member having a plurality of light emitting parts separated by a groove. The light emitting part includes a plurality of outer parts including a first outer part, a first inner part adjacent to the first outer part and located in a region surrounded by the plurality of outer parts in a plan view, and a first inner part adjacent to the first outer part. a second inner part adjacent to the first inner part, and a plurality of inner parts including a second inner part adjacent to the first inner part; a first groove located between the first outer part and the first inner part, and a first groove located between the first inner part and the second inner part. and a second groove located between the first outer part and the first outer part, and the brightness of the first groove when only the first outer part is made to emit light is the same as the brightness of the first groove when only the first inner part is made to emit light. Brighter than the second groove.

According to the planar light source of one embodiment of the present invention, it is possible to provide a planar light source that can reduce uneven brightness.

FIG. 2 is a plan view of a planar light source according to an embodiment. FIG. 2 is an enlarged plan view of section A in FIG. 1. FIG. 3 is a sectional view taken along line III-III in FIG. 2. FIG. 3 is a sectional view taken along the line IV-IV in FIG. 2. FIG. It is a bottom view of the light source of embodiment. 5A is a cross-sectional view taken along the line VB-VB in FIG. 5A. FIG. It is a sectional view showing a modification of the light source of the embodiment. It is a sectional view showing a modification of the light source of the embodiment. FIG. 3 is a cross-sectional view of a planar light source according to a second embodiment. FIG. 7 is a cross-sectional view of a planar light source according to a third embodiment. It is a top view of the 2nd division member of 4th Embodiment. It is a top view of the 1st partition member of 4th Embodiment. FIG. 8B is a cross-sectional view taken along line IX-IX in FIG. 8B. It is a sectional view of the groove of a 6th embodiment. FIG. 7 is a sectional view of a groove according to a modification of the sixth embodiment.

Hereinafter, embodiments will be described with reference to the drawings. Since each drawing schematically shows an embodiment, the scale, spacing, positional relationship, etc. of each member may be exaggerated, or illustration of some members may be omitted. Moreover, as a sectional view, an end view showing only a cut surface may be shown.

In the following description, components having substantially the same functions are indicated by common reference numerals, and the description thereof may be omitted. In addition, terms indicating a specific direction or position (eg, "above", "below", and other terms including those terms) may be used. However, these terms are used only for clarity of relative orientation or position in the referenced drawings. If the relative directions or positional relationships using terms such as "upper" and "lower" in the referenced drawings are the same, the arrangement may not be the same in drawings other than this disclosure, actual products, etc. as in the referenced drawings. It's okay. In this specification, "parallel" refers not only to cases in which two straight lines, sides, planes, etc. do not intersect even if extended, but also to cases in which two lines, sides, planes, etc. intersect within an angle of 10°. Also included. In this specification, the positional relationship expressed as "above" includes cases in which they are in contact with each other, and cases in which they are not in contact with each other but are located above.

FIG. 1 is a plan view of a planar light source according to an embodiment. The plan view shown in FIG. 1 is common to each embodiment described below.

The planar light source of the embodiment includes a light guide member 10. The light guide member 10 has a first surface 11 and a second surface 12 (shown in FIG. 3 and the like described later) on the opposite side of the first surface 11. In this specification, two directions that are parallel to the first surface 11 of the light guide member 10 and orthogonal to each other are referred to as a first direction X and a second direction Y. Further, a direction from the second surface 12 toward the first surface 11 and perpendicular to the first direction X and the second direction Y is defined as a third direction Z. The shape of the light guide member 10 in plan view includes, for example, two sides extending in the first direction X, two sides extending in the second direction Y, and four corners (first corner 10a, second corner 10b, It is a quadrilateral having a third corner 10c and a fourth corner 10d).

The light guide member 10 has a plurality of light emitting parts 1 separated from each other in the first direction X and the second direction Y by the grooves 14. Each light emitting unit 1 can be used as a drive unit for local dimming, for example.

The plurality of light emitting parts 1 have a plurality of outer parts. The plurality of outer parts include a plurality of first outer parts 1c and a plurality of second outer parts 1d. The second outer portion 1d is located at a corner of the light guide member 10 in plan view. In the planar light source of the embodiment, the second outer portion 1d is located at each of the first corner 10a, the second corner 10b, the third corner 10c, and the fourth corner 10d. That is, the plurality of outer parts includes four second outer parts 1d.

A plurality of first outer parts 1c are arranged along the first direction X between the second outer part 1d located at the first corner 10a and the second outer part 1d located at the second corner 10b. ing. A plurality of first outer parts 1c are arranged along the first direction X between the second outer part 1d located at the third corner 10c and the second outer part 1d located at the fourth corner 10d. ing. A plurality of first outer parts 1c are arranged along the second direction Y between the second outer part 1d located at the first corner 10a and the second outer part 1d located at the third corner 10c. ing. A plurality of first outer parts 1c are arranged along the second direction Y between the second outer part 1d located at the second corner 10b and the second outer part 1d located at the fourth corner 10d. ing. Each second outer portion 1d is adjacent to one first outer portion 1c in the first direction X, and adjacent to one first outer portion 1c in the second direction Y. The plurality of first outer parts 1c and the plurality of second outer parts 1d are the light emitting parts 1 located at the outermost periphery of the area in which the plurality of light emitting parts 1 are arranged in plan view.

The plurality of light emitting parts 1 further include a plurality of inner parts located in a region surrounded by the plurality of outer parts in a plan view. For example, the number of inner portions is greater than the number of outer portions.

The plurality of inner parts include a plurality of first inner parts 1a and a plurality of second inner parts 1b. Each first inner part 1a is adjacent to the first outer part 1c in the first direction X or the second direction Y. In plan view, the plurality of second inner parts 1b are arranged in a region surrounded by the plurality of first inner parts 1a.

The plurality of second inner parts 1b are composed of a second inner part 1b adjacent to the first inner part 1a in the first direction X, a second inner part 1b adjacent to the first inner part 1a in the second direction Y, It includes a second inner part 1b adjacent to the first inner part 1a in the first direction X and the second direction Y. In a plan view, a plurality of second inner parts 1b that are not adjacent to the first inner part 1a are arranged in an area surrounded by a plurality of second inner parts 1b that are adjacent to the first inner part 1a. In the first direction X, the first inner part 1a is located between the second inner part 1b and the first outer part 1c. In the second direction Y, the first inner part 1a is located between the second inner part 1b and the first outer part 1c.

In plan view, each outer part has a number of light emitting parts 1 smaller than the number of light emitting parts 1 adjacent to each other in the first direction are adjacent to each other. In addition, in a plan view, each of the second outer parts 1d has one first outer part 1c with a smaller number of light emitting parts 1 than the number of adjacent light emitting parts 1 in the first direction X and the second direction Y. They are adjacent to each other in the first direction X and the second direction Y.

In plan view, one inner part is adjacent to four light emitting parts 1 in the first direction X and the second direction Y. In plan view, one first outer part 1c is adjacent to three light emitting parts 1 in the first direction X and the second direction Y. In plan view, one second outer part 1d is adjacent to two light emitting parts 1 in the first direction X and the second direction Y.

FIG. 2 is an enlarged plan view of section A in FIG. FIG. 2 shows two first outer parts 1c adjacent in the second direction Y, two first inner parts 1a adjacent to each first outer part 1c in the first direction X, and two first inner parts 1a adjacent to each first outer part 1c in the first direction X. Each first inner part 1a and two adjacent second inner parts 1b are shown.
FIG. 3 is a cross-sectional view taken along line III--III in FIG. 2, and is a cross-sectional view of the first inner portion 1a.
FIG. 4 is a sectional view taken along the line IV-IV in FIG. 2, and is a sectional view of the first outer portion 1c.

The planar light source of the embodiment includes a light guide member 10 and a plurality of light sources 20A. Furthermore, the planar light source of the embodiment can include a support member 50, a first light-transmitting member 30, and a first light-reflecting member 40.

Each member constituting the planar light source of the embodiment will be explained in detail below.

<Light guiding member>
The light guide member 10 is a member that is transparent to the light emitted by the light source 20A. The transmittance of the light guide member 10 with respect to the peak wavelength of the light source 20A is preferably 50% or more, and more preferably 70% or more, for example.

As the material of the light guide member 10, for example, thermoplastic resin such as acrylic, polycarbonate, cyclic polyolefin, polyethylene terephthalate or polyester, thermosetting resin such as epoxy or silicone, or glass can be used.

The thickness of the light guide member 10 is preferably, for example, 150 μm or more and 800 μm or less. In this specification, the thickness of each member represents the maximum value of the distance between the upper surface and the lower surface of each member in the third direction Z. The light guide member 10 may be composed of a single layer in the third direction Z, or may be composed of a laminate of a plurality of layers. When the light guide member 10 is composed of a laminate, a translucent adhesive layer may be arranged between each layer. Each layer of the laminate may use a different type of base material. As the material for the adhesive layer, for example, a thermoplastic resin such as acrylic, polycarbonate, cyclic polyolefin, polyethylene terephthalate, or polyester, or a thermosetting resin such as epoxy or silicone can be used.

The light guide member 10 has a first hole h1 penetrating from the first surface 11 to the second surface 12. As shown in FIG. 2, the first hole h1 can be, for example, circular in plan view. Further, the first hole h1 can be, for example, an ellipse or a polygon such as a triangle, a quadrangle, a hexagon, or an octagon in plan view. In this specification, planar view means viewing from the third direction Z.

As mentioned above, the grooves 14 are formed in the light guide member 10 to separate the respective light emitting parts 1 from each other. By forming the groove 14, for example, it is possible to suppress warpage of the planar light source due to heat generation of the light source 20A. As shown in FIG. 3, the groove 14 has a first groove part 14a that opens on the first surface 11 side and a second groove part 14b that opens on the second surface 12 side. The first groove portion 14a and the second groove portion 14b communicate in the third direction Z. The width of the first groove portion 14a is wider than the width of the second groove portion 14b. The width of the first groove portion 14a and the width of the second groove portion 14b are widths in a direction perpendicular to the direction in which the groove 14 extends.

The groove 14 penetrates from the first surface 11 to the second surface 12 of the light guide member 10 . Further, the groove 14 may be a bottomed groove having an opening on the first surface 11 side and the bottom of which does not reach the second surface 12. Further, the groove 14 may be a bottomed groove having an opening on the second surface 12 side and the bottom of which does not reach the first surface 11. Moreover, the groove 14 may be a hollow groove arranged inside the light guide member 10. In addition, since the groove 14 penetrates from the first surface 11 to the second surface 12 of the light guide member 10, compared to the case where the light guide member 10 is connected at the position of the groove 14, the manufacturing process of the planar light source is improved. Warpage caused by heat treatment can be suppressed.

The groove 14 has a first groove 14-1 and a second groove 14-2. The first groove 14-1 is located between the first outer part 1c and the first inner part 1a. The second groove 14-2 is located between the first inner part 1a and the second inner part 1b. The second groove 14-2 is further located between adjacent second inner portions 1b. The groove 14 also has a third groove 14-3 located between adjacent outer parts. As shown in FIG. 1, the third groove 14-3 is located between adjacent first outer portions 1c and between the first outer portion 1c and the second outer portion 1d.

As shown in FIG. 3, the first partition member 15a can be placed in the first groove 14-1, and the second partition member 15b can be placed in the second groove 14-2. Further, the second partition member 15b can be arranged within the third groove 14-3.

The first partition member 15a and the second partition member 15b have reflectivity for the light emitted by the light source 20A. The first partition member 15a and the second partition member 15b are, for example, resin members containing light scattering particles. Examples of the light scattering particles of the first partition member 15a and the second partition member 15b include titania, silica, alumina, zinc oxide, magnesium oxide, zirconia, yttria, calcium fluoride, magnesium fluoride, niobium pentoxide, and barium titanate. , tantalum pentoxide, barium sulfate, glass, or the like can be used. As the resin material of the first partition member 15a and the second partition member 15b, for example, a thermoplastic resin such as acrylic resin, polycarbonate resin, cyclic polyolefin resin, polyethylene terephthalate resin, or polyester resin, or a thermoplastic resin such as epoxy resin or silicone resin is used. A curable resin can be used. Moreover, the first partition member 15a and the second partition member 15b may be metal members such as aluminum or silver. For example, the first partition member 15a and the second partition member 15b are arranged in a membrane shape along the inner surface of the first groove portion 14a. Further, the first partition member 15a and the second partition member 15b may be filled in the groove 14.

The first partition member 15a and the second partition member 15b suppress light guide between adjacent light emitting parts 1. For example, light guide from the light emitting section 1 in the light emitting state to the light emitting section 1 in the non-light emitting state is suppressed by the first partition member 15a and the second partition member 15b. This makes it easy to control the brightness of each light emitting section 1 when local dimming is performed using each light emitting section 1 as a driving unit.

<Light source>
The light source 20A is arranged in the first hole h1 of the light guide member 10. The first hole h1 is arranged in each of the plurality of light emitting parts 1. Therefore, the light source 20A is arranged in each of the plurality of light emitting sections 1.

The light source 20A includes a light emitting element 21. The light emitting element 21 includes a semiconductor stack. The semiconductor stack includes, for example, a substrate made of sapphire or gallium nitride, an n-type semiconductor layer disposed on the substrate, a p-type semiconductor layer, and a light emitting layer sandwiched therebetween. Furthermore, the light emitting element 21 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. Furthermore, the light source 20A includes a pair of positive and negative electrodes 25 arranged on the lower surface side. One of the pair of electrodes 25 is electrically connected to the p-side electrode, and the other is electrically connected to the n-side electrode.

A semiconductor stacked body from which the substrate has been removed may be used. In addition, the structure of the light emitting layer may be a structure with a single active layer such as a double heterostructure or a single quantum well structure (SQW), or a structure with a single active layer such as a multiple quantum well structure (MQW). A structure having a group of layers may be used. The light emitting layer is capable of emitting visible light or ultraviolet light. The light emitting layer is capable of emitting visible light ranging from blue to red. A semiconductor stack including such a light emitting layer can include, for example, In _x Al _y Ga _1-x-y N (0≦x, 0≦y, x+y≦1). The semiconductor stack can include at least one light-emitting layer capable of emitting the light described above. For example, the semiconductor stack may have a structure that includes one or more light emitting layers between an n-type semiconductor layer and a p-type semiconductor layer, or a structure that includes an n-type semiconductor layer, a light-emitting layer, and a p-type semiconductor layer. It may be a structure in which the structures included in this order are repeated multiple times. When the semiconductor laminate includes a plurality of light-emitting layers, it may contain light-emitting layers with different light-emitting peak wavelengths, or may contain light-emitting layers with the same light-emitting peak wavelength. Note that the same emission peak wavelength may mean, for example, a variation of several nanometers. Such combinations of light-emitting layers can be selected as appropriate. For example, when a semiconductor stack includes two light-emitting layers, combinations of blue light and blue light, green light and green light, red light and red light, ultraviolet light and The light-emitting layer can be selected using a combination of ultraviolet light, blue light and green light, blue light and red light, or green light and red light. Further, the light emitting layer may include a plurality of active layers having different emission peak wavelengths, or may include a plurality of active layers having the same emission peak wavelength.

The light source 20A can further include a second translucent member 22. The second translucent member 22 covers the top and side surfaces of the light emitting element 21 . The second light-transmitting member 22 protects the light emitting element 21 and has functions such as wavelength conversion and light diffusion depending on the particles added to the second light-transmitting member 22.

For example, the second translucent member 22 may contain a translucent resin and may further contain a phosphor. As the light-transmitting resin, for example, silicone resin or epoxy resin can be used. In addition, examples of the phosphor include yttrium-aluminum-garnet-based phosphor (e.g., Y ₃ (Al, Ga) ₅ O ₁₂ :Ce), lutetium-aluminum-garnet-based phosphor (e.g., Lu ₃ (Al, Ga)). ₅ O ₁₂ :Ce), terbium-aluminum-garnet-based phosphor (e.g., Tb ₃ (Al, Ga) ₅ O ₁₂ :Ce), CCA-based phosphor (e.g., Ca ₁₀ (PO ₄ ) ₆ C ₁₂ :Eu) ), SAE-based phosphors (e.g., Sr ₄ Al ₁₄ O ₂₅ :Eu), chlorosilicate-based phosphors (e.g., Ca ₈ MgSi ₄ O ₁₆ Cl ₂ :Eu), β-sialon-based phosphors (e.g., (Si, Oxynitride-based phosphors such as Al) ₃ (O,N) ₄ :Eu) or α-sialon-based phosphors (e.g., Ca(Si,Al) ₁₂ (O,N) ₁₆ :Eu), SLA-based phosphors (e.g., SrLiAl ₃ N ₄ :Eu), CASN-based phosphor (e.g., CaAlSiN ₃ :Eu), or SCASN-based phosphor (e.g., (Sr,Ca)AlSiN ₃ :Eu), etc., nitride-based phosphor, KSF type phosphor (e.g. K ₂ SiF ₆ :Mn), KSAF type phosphor (e.g. K ₂ Si _0.99 Al _0.01 F _5.99 :Mn) or MGF type phosphor (e.g. 3.5MgO. Fluoride-based phosphors such as 0.5MgF ₂ .GeO ₂ :Mn), phosphors with a perovskite structure (e.g. CsPb(F,Cl,Br,I) ₃ ), or quantum dot phosphors (e.g. CdSe , InP, AgInS ₂ or AgInSe ₂ ), etc. can be used. As the phosphor added to the second light-transmitting member 22, one type of phosphor may be used, or multiple types of phosphor may be used.

The KSAF-based phosphor may have a composition represented by the following formula (I).
M ₂ [Si _p Al _q Mn _r F _s ] (I)

In formula (I), M represents an alkali metal and may contain at least K. Mn may be a tetravalent Mn ion. p, q, r, and s may satisfy 0.9≦p+q+r≦1.1, 0<q≦0.1, 0<r≦0.2, and 5.9≦s≦6.1. Preferably, 0.95≦p+q+r≦1.05 or 0.97≦p+q+r≦1.03, 0<q≦0.03, 0.002≦q≦0.02 or 0.003≦q≦0.015. , 0.005≦r≦0.15, 0.01≦r≦0.12 or 0.015≦r≦0.1, 5.92≦s≦6.05 or 5.99≦s≦6.025 It may be. For example, K ₂ [Si _0.946 Al _0.005 Mn _0.049 F _5.995 ], K ₂ [Si _0.942 Al _0.008 Mn _0.050 F _5.992 ], K ₂ [Si _{0. 939} Al _0.014 Mn _0.047 F _5.986 ]. According to such a KSAF-based phosphor, it is possible to obtain red light emission with high brightness and a narrow half-width of the emission peak wavelength.

Further, a wavelength conversion sheet containing the above-mentioned phosphor may be placed on the planar light source. The wavelength conversion sheet can be a planar light source that absorbs part of the blue light from the light source 20A, emits yellow light, green light, and/or red light, and emits white light. For example, white light can be obtained by combining the light source 20A capable of emitting blue light and a wavelength conversion sheet containing a phosphor capable of emitting yellow light. Alternatively, the light source 20A capable of emitting blue light and a wavelength conversion sheet containing a red phosphor and a green phosphor may be combined. Further, the light source 20A capable of emitting blue light may 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 capable of emitting red light and a wavelength conversion sheet containing a phosphor capable of emitting green light can be selected. Further, the light source 20A includes a light emitting element 21 capable of emitting blue light, a second light-transmitting member 22 containing a phosphor capable of emitting red light, and a wavelength containing a phosphor capable of emitting green light. It may also be combined with a conversion sheet.

As the yellow phosphor used in the wavelength conversion sheet, it is preferable to use, for example, the above-mentioned yttrium-aluminum-garnet-based phosphor. Further, as the green phosphor used in the wavelength conversion sheet, it is preferable to use a phosphor having a narrow half-value width of the emission peak wavelength, for example, a phosphor having the above-mentioned perovskite structure or a quantum dot phosphor. Further, as the red phosphor used in the wavelength conversion sheet, the above-mentioned KSF phosphor, KSAF phosphor, or quantum dot phosphor, which has a narrow half-width of the emission peak wavelength like the green phosphor, is used. is preferable. In particular, quantum dot phosphors have a short afterglow time, so they can be suitably used in planar light sources that perform local dimming.

The light source 20A can further include a covering member 24. Covering member 24 is arranged on the lower surface of light emitting element 21 . The covering member 24 is arranged so that the lower surface of the electrode 25 of the light source 20A is exposed from the covering member 24. The covering member 24 is also arranged on the lower surface of the second translucent member 22 that covers the side surface of the light emitting element 21 .

The covering member 24 has reflectivity for the light emitted by the light source 20A. The covering member 24 is, for example, a resin member containing light scattering particles. The light scattering particles of the coating member 24 include, for example, titania, silica, alumina, zinc oxide, magnesium oxide, zirconia, yttria, calcium fluoride, magnesium fluoride, niobium pentoxide, barium titanate, tantalum pentoxide, barium sulfate, or , glass, and the like can be used. As the resin material for the covering member 24, for example, thermoplastic resin such as acrylic resin, polycarbonate resin, cyclic polyolefin resin, polyethylene terephthalate resin, or polyester resin, or thermosetting resin such as epoxy resin or silicone resin can be used. can.

Furthermore, the light source 20A can include a second light reflecting member 23. The second light reflecting member 23 is arranged on the upper surface of the light source 20A. The second light reflecting member 23 covers the upper surface of the light emitting element 21 . The second light reflecting member 23 is disposed on the upper surface of the second transparent member 22 and controls the amount and direction of light emitted from the upper surface of the second transparent member 22 . The second light reflecting member 23 has a reflective property and a translucent property for the light emitted by the light emitting element 21 . A part of the light emitted from the upper surface of the second light-transmitting member 22 is reflected by the second light-reflecting member 23, and the other part is transmitted through the second light-reflecting member 23. The transmittance of the second light reflecting member 23 with respect to the light emitted by the light emitting element 21 is, for example, preferably 1% or more and 50% or less, and more preferably 3% or more and 30% or less. This reduces the brightness directly above the light source 20A and reduces uneven brightness of the planar light source.

The second light reflecting member 23 can be made of a light-transmitting resin and light-scattering particles contained in the light-transmitting resin. As the light-transmitting resin, for example, thermoplastic resin such as acrylic resin, polycarbonate resin, cyclic polyolefin resin, polyethylene terephthalate resin, or polyester resin, or thermosetting resin such as epoxy resin or silicone resin can be used. Examples of light scattering particles include titania, silica, alumina, zinc oxide, magnesium oxide, zirconia, yttria, calcium fluoride, magnesium fluoride, niobium pentoxide, barium titanate, tantalum pentoxide, barium sulfate, or glass. Particles such as the following can be used. Further, the second light reflecting member 23 may be, for example, a metal member such as Al or Ag, or a dielectric multilayer film.

The light source may not include the covering member 24. For example, in the light source 20B shown in FIG. 5C, the lower surface of the light source 20B is formed by the lower surface of the light emitting element 21 and the lower surface of the second light-transmitting member 22.

Further, the light source may be the light emitting element 21 alone. The light source 20C shown in FIG. 5D does not include the second light-transmitting member 22 and the covering member 24. In the light source 20C, a second light reflecting member 23 may be disposed on the upper surface of the light emitting element 21. Further, in FIG. 5D, although the covering member 24 is not arranged on the lower surface of the light emitting element 21 in the light source 20C, the covering member 24 may be arranged on the lower surface of the light emitting element 21.

<First translucent member>
The first translucent member 30 is arranged between the side surface of the light source 20A in the first hole h1 of the light guide member 10 and the light guide member 10, and above the light source 20A. The first translucent member 30 covers the top and side surfaces of the light source 20A. It is preferable that the first translucent member 30 is in contact with the light guide member 10 and the light source 20A. By doing so, it becomes easier to guide the light from the light source 20A to the light guide member 10.

The first translucent member 30 has translucency to the light emitted by the light source 20A. The transmittance of the first transparent member 30 with respect to the peak wavelength of the light source 20A is preferably 50% or more, and more preferably 70% or more, for example. As the material of the first translucent member 30, for example, resin can be used. For example, as the material of the first translucent member 30, the same resin as the material of the light guide member 10, or a resin having a small difference in refractive index from the material of the light guide member 10 can be used.

The first translucent member 30 may be composed of a single layer in the third direction Z, or may be composed of a laminate of a plurality of layers. Further, the first translucent member 30 may contain a fluorescent material or a light diffusing material. When the first translucent member 30 is a laminate, each layer may or may not contain a fluorescent material and/or a light diffusing material. For example, the first light-transmitting member 30 may be composed of a layer containing a phosphor and a layer not containing a phosphor.

<First light reflecting member>
The first light reflecting member 40 is arranged on the first light transmitting member 30. The first light reflecting member 40 is arranged above the light source 20A via the first transparent member 30. Further, the first light reflecting member 40 may be in contact with the first translucent member 30 and the light source 20A. Further, the first light reflecting member 40 may be placed above the first light transmitting member 30 and the light source 20A via an adhesive resin. As the adhesive resin, for example, a thermoplastic resin such as an acrylic resin, a polycarbonate resin, a cyclic polyolefin resin, a polyethylene terephthalate resin, or a polyester resin, or a thermosetting resin such as an epoxy resin or a silicone resin can be used. Moreover, as shown in FIG. 2, the first light reflecting member 40 is arranged at a position overlapping with the first hole h1 in which the light source 20A and the first translucent member 30 are arranged in plan view.

The first light reflecting member 40 has a reflective property and a translucent property for the light emitted by the light source 20A. The transmittance of the first light reflecting member 40 with respect to the peak wavelength of the light source 20A is, for example, preferably 1% or more and 50% or less, and more preferably 3% or more and 30% or less.

The first light reflecting member 40 can be made of a light-transmitting resin and light-scattering particles contained in the light-transmitting resin. As the light-transmitting resin, for example, thermoplastic resin such as acrylic resin, polycarbonate resin, cyclic polyolefin resin, polyethylene terephthalate resin, or polyester resin, or thermosetting resin such as epoxy resin or silicone resin can be used. Examples of light scattering particles include titania, silica, alumina, zinc oxide, magnesium oxide, zirconia, yttria, calcium fluoride, magnesium fluoride, niobium pentoxide, barium titanate, tantalum pentoxide, barium sulfate, or glass. Particles such as the following can be used. Further, in the first light reflecting member 40, the above-described translucent resin may contain many air bubbles without containing light scattering particles. Further, the first light reflecting member 40 may be, for example, a metal member such as aluminum or silver, or a dielectric multilayer film.

The upper surface of the first light reflecting member 40 functions together with the first surface 11 of the light guiding member 10 as a light emitting surface (light emitting surface) of the planar light source. The first light reflecting member 40 reflects a part of the light directed upward of the first hole h1 where the light source 20A is disposed, and transmits the other part. This makes it possible to reduce the difference between the brightness of the area immediately above and around the light source 20A and the brightness of other areas on the light emitting surface of the planar light source. Thereby, uneven brightness on the light emitting surface of the planar light source can be reduced.

The first light-transmitting member 30 is arranged between the first light-reflecting member 40 and the second light-reflecting member 23 of the light source 20A. The first light-transmitting member 30 has a higher transmittance than the first light-reflecting member 40 and the second light-reflecting member 23 for the light emitted by the light source 20A. The transmittance of the first light-transmitting member 30 for the light emitted by the light source 20A is 2 times or more and 100 times the transmittance of the second light-reflecting member 23 and the transmittance of the first light-reflecting member 40 within a range of 100% or less. It can be as follows. The first light-transmitting member 30 between the first light-reflecting member 40 and the second light-reflecting member 23 receives light emitted from the side surface of the light source 20A and light reflected by a third light-reflecting member 53, which will be described later. Light is guided around the area. Thereby, the area directly above the light source 20A does not become too bright or too dark, and as a result, uneven brightness on the light emitting surface of the planar light source can be reduced.

Part of the light emitted directly upward from the light source 20A is suppressed from being transmitted by the second light reflecting member 23, so in order to prevent the area directly above the light source 20A from becoming too dark, the light source 20A is It is preferable that the transmittance of the first light reflecting member 40 is higher than the transmittance of the second light reflecting member 23 with respect to the emitted light.

<Support member>
The support member 50 supports the light guide member 10 and the light source 20A. The light guide member 10 is arranged on the support member 50 with the second surface 12 facing the upper surface of the support member 50. The light source 20A is arranged on the support member 50 in the first hole h1.

The support member 50 has a wiring board 60. The wiring board 60 includes an insulating base material 61 and at least one wiring layer 62 disposed on at least one surface of the insulating base material 61. The insulating base material 61 may be a rigid substrate or a flexible substrate. In order to reduce the thickness of the planar light source, the insulating base material 61 is preferably a flexible substrate. The insulating base material 61 may be composed of a single layer in the third direction Z, or may be composed of a laminate of a plurality of layers. For example, the insulating base material 61 may be composed of a single-layer flexible substrate, or may be composed of a laminate of a plurality of rigid substrates. As the material of the insulating base material 61, for example, resin such as polyimide can be used. The wiring layer 62 is a metal film, for example, a copper film.

The support member 50 includes a first adhesive layer 51 disposed on the wiring board 60 , a third light reflecting member 53 disposed on the first adhesive layer 51 , and a third light reflecting member 53 disposed on the third light reflecting member 53 . 2 adhesive layer 52.

The first adhesive layer 51 is arranged on the surface of the insulating base material 61 opposite to the surface on which the wiring layer 62 is arranged. The first adhesive layer 51 is disposed between the insulating base material 61 and the third light reflecting member 53, and adheres the insulating base material 61 and the third light reflecting member 53. The first adhesive layer 51 is, for example, a resin layer containing light scattering particles. Examples of light scattering particles include titania, silica, alumina, zinc oxide, magnesium oxide, zirconia, yttria, calcium fluoride, magnesium fluoride, niobium pentoxide, barium titanate, tantalum pentoxide, barium sulfate, or glass. particles can be used. As the resin for the first adhesive layer 51, for example, thermoplastic resin such as acrylic resin, polycarbonate resin, cyclic polyolefin resin, polyethylene terephthalate resin, or polyester resin, or thermosetting resin such as epoxy resin or silicone resin may be used. can.

The third light reflecting member 53 is arranged below the second surface 12 of the light guide member 10, below the light source 20A, below the first translucent member 30, and below the groove 14. The third light reflecting member 53 has reflectivity for light emitted by the light source 20A. As the third light reflecting member 53, for example, a resin member containing many bubbles or a resin member containing light scattering particles can be used. The resin of the third light reflecting member 53 can be selected from, for example, the resins listed as resins that can be used for the first adhesive layer 51 described above. The light scattering particles can be selected, for example, from the light scattering particles listed as light scattering particles that can be used in the first adhesive layer 51 described above.

In the area between the third light reflecting member 53 and the first surface 11 of the light guide member 10, the light from the light source 20A is reflected repeatedly by the third light reflecting member 53 and the first surface 11. The light is guided within the light guide member 10 toward the groove 14 . A part of the light directed toward the first surface 11 is extracted from the first surface 11 to the outside of the light guide member 10 . A part of the light directed toward the second surface 12 is reflected toward the first surface 11 by the third light reflecting member 53, so that the brightness of the light extracted from the first surface 11 can be improved. It is preferable that the third light reflecting member 53 uses a resin member containing a large number of bubbles. The amount of light reflected by the third light reflecting member 53 is improved, and the light from the light source 20A becomes easier to guide inside the light guiding member 10 toward the groove 14. Furthermore, when the first adhesive layer 51 disposed on the lower surface of the third light reflecting member 53 has light reflectivity, the brightness of the light extracted from the first surface 11 can be further improved.

The second adhesive layer 52 is disposed between the third light reflecting member 53 and the second surface 12 of the light guiding member 10 and bonds the third light reflecting member 53 and the light guiding member 10 together. The light source 20A is arranged on the second adhesive layer 52 within the first hole h1 of the light guide member 10. The second adhesive layer 52 is transparent to the light emitted by the light source 20A. The material for the second adhesive layer 52 can be selected from, for example, the resins listed as resins that can be used for the first adhesive layer 51 described above. Further, the second adhesive layer 52 may include light scattering particles, and the light scattering particles may be selected from, for example, the light scattering particles listed as light scattering particles that can be used in the first adhesive layer 51 described above. I can do it.

Support member 50 further includes a conductive member 70. The conductive member 70 includes, for example, resin and metal particles contained in the resin. As the resin for the conductive member 70, for example, epoxy resin or phenol resin can be used. As metal particles, for example, copper or silver particles can be used.

The conductive member 70 has a connection part 71 and a wiring part 72. The connecting portion 71 penetrates the second adhesive layer 52, the third light reflecting member 53, the first adhesive layer 51, and the insulating base material 61 in the third direction Z. The wiring section 72 is arranged on the surface of the wiring board 60 on which the wiring layer 62 is arranged, and is connected to the connection section 71 . The connecting portion 71 and the wiring portion 72 can be integrally formed of the same material, for example. A portion 72a of the wiring section 72 is connected to the wiring layer 62.

A pair of conductive members 70 are arranged apart from each other, corresponding to a pair of positive and negative electrodes 25 of the light source 20A. The connecting portion 71 of one conductive member 70 is connected to the positive electrode 25 below the light source 20A, and the connecting portion 71 of the other conductive member 70 is connected to the negative electrode 25 below the light source 20A. There is. The electrode 25 of the light source 20A is electrically connected to the conductive member 70 and the wiring layer 62.

Support member 50 further includes an insulating layer 54. The insulating layer 54 covers and protects the surface of the wiring board 60 on which the wiring layer 62 is arranged, the wiring layer 62, and the conductive member 70.

Each of the first inner part 1a, the second inner part 1b, the first outer part 1c, and the second outer part 1d includes the above-mentioned members. The outer surface of the second outer section 1d where other light emitting parts 1 are not adjacent has the same configuration as the outer surface of the first outer section 1c.

In a plan view, the number of light emitting parts 1 whose outer parts are adjacent to each other is smaller than the number of light emitting parts 1 whose inner parts are adjacent to each other. Therefore, the amount of light that enters one outer section from adjacent light emitting sections 1 is smaller than the amount of light that enters one inner section from adjacent light emitting sections 1. Therefore, in the fully lit state in which all the light emitting parts 1 emit light, the area on the outer peripheral side of the light guide member 10 where the first outer part 1c and the second outer part 1d are arranged is the same as the first inner part 1a and the second outer part 1d. The area tends to be darker than the area where the inner part 1b is arranged.

According to each of the embodiments described below, light easily enters the area on the outer peripheral side of the light guide member 10 from the adjacent light emitting parts 1. As a result, the brightness of the first groove 14-1 in a state in which only one first outer part 1c is emitted is the same as the brightness in the second groove 14-2 in a state in which only one first inner part 1a is emitted. It is possible to increase the amount of light entering the first outer part 1c from the adjacent light emitting parts 1. As a result, in the fully lit state, it is possible to compensate for the decrease in brightness in the area on the outer peripheral side of the light guide member 10, and it is possible to reduce uneven brightness on the light emitting surface of the planar light source.

Note that the brightness of the first groove 14-1 and the second groove 14-2 is determined by supplying the same power to each light source 20A, and controlling one first outer part 1c and one first inner part 1a. It represents the brightness when each light is emitted individually. For example, the brightness of the first groove 14-1 and the second groove 14-2 can be measured using a spectrophotometer. With the spectrophotometer installed above the first groove 14-1, power is supplied to the light source 20A placed in the first outer portion 1c to measure the brightness. Further, with the spectrophotometer installed above the second groove 14-2, power is supplied to the light source 20A disposed in the first inner portion 1a to measure the luminance.

[First embodiment]
In the first embodiment, as shown in FIG. 3, the depth from the first surface 11 of the first groove part 14a of the first groove 14-1 is set to The depth is made shallower than the depth from surface 11. In the first groove 14-1, the first partition member 15a is disposed within the first groove portion 14a, and is not disposed between the first groove portion 14a and the second surface 12. In the second groove 14-2, the second partition member 15b is disposed within the first groove portion 14a, and is not disposed between the first groove portion 14a and the second surface 12. Therefore, by making the depth of the first groove part 14a of the first groove 14-1 from the first surface 11 shallower than the depth of the first groove part 14a of the second groove 14-2 from the first surface 11, The thickness of the light guide member 10 in the third direction Z between the first groove portion 14a of the first groove 14-1 and the second surface 12 where the first dividing member 15a is not arranged is the same as that of the second groove 14-2. It becomes thicker than the thickness in the third direction Z of the light guide member 10 where the second partition member 15b is not arranged between the first groove portion 14a and the second surface 12.

As a result, the amount of light traveling from the first inner part 1a to the first outer part 1c through the first groove 14-1 is increased more than when the first groove 14-1 has the same configuration as the second groove 14-2. can do. As a result, the brightness of the first groove 14-1 when only one first outer part 1c is emitted is the same as the brightness of the second groove 14-2 when only one first inner part 1a is emitted. It is possible to increase the amount of light entering the first outer part 1c from the first inner part 1a, and compensate for the decrease in brightness of the area on the outer peripheral side of the light guide member 10 in the fully lit state. Luminance unevenness on the light emitting surface of the planar light source can be reduced.

The width of the first groove portion 14a is wider than the width of the second groove portion 14b. By making the depth of the first groove part 14a of the first groove 14-1 from the first surface 11 shallower than the depth of the first groove part 14a of the second groove 14-2 from the first surface 11, The strength of the region on the outer peripheral side of the light guide member 10 where the groove 14-1 is arranged can be improved. Thereby, deformation of the planar light source can be suppressed.

By making the reflectance of the first partition member 15a lower than the reflectance of the second partition member 15b, the brightness of the first groove 14-1 in a state where only one first outer portion 1c is emitted can be reduced to 1 When the brightness of the second groove 14-2 is made brighter than the brightness of the second groove 14-2 in a state where only the first inner portions 1a are emitted, and the reflectance of the first partition member 15a is made the same as the reflectance of the second partition member 15b, In comparison, the amount of light entering the first outer part 1c from the first inner part 1a can be increased. The reflectance here represents the reflectance for light from the light source 20A.

[Second embodiment]
In the second embodiment, as shown in FIG. 6, by making the thickness of the first partition member 15a thinner than the thickness of the second partition member 15b, the reflectance of the first partition member 15a is lowered by the second partition member. The reflectance is lower than that of 15b. As a result, the amount of light directed from the first inner part 1a to the first outer part 1c through the first groove 14-1, in which the first partition member 15a is arranged, is reduced to the second groove 14-1, in which the second partition member 15b is arranged. -2, the amount of light traveling from the first inner part 1a to the second inner part 1b can be increased. Thereby, uneven brightness on the light emitting surface of the planar light source can be reduced. The thickness of the first partition member 15a represents the maximum length of the first partition member 15a in the direction orthogonal to the side surface of the light emitting part 1 that defines the groove 14. The thickness of the second partition member 15b represents the maximum length of the second partition member 15b in the direction orthogonal to the side surface of the light emitting part 1 that defines the groove 14. Moreover, the first embodiment and the second embodiment can also be combined.

[Third embodiment]
In the third embodiment, as shown in FIG. 7, by making the height of the first partition member 15a lower than the height of the second partition member 15b, the reflectance of the first partition member 15a is lowered by the second partition member. The reflectance is lower than that of 15b. As a result, the amount of light directed from the first inner part 1a to the first outer part 1c through the first groove 14-1, in which the first partition member 15a is arranged, is reduced to the second groove 14-1, in which the second partition member 15b is arranged. -2, the amount of light traveling from the first inner part 1a to the second inner part 1b can be increased. Thereby, uneven brightness on the light emitting surface of the planar light source can be reduced. The height of the first partition member 15a is the maximum length of the first partition member 15a in the third direction Z, and the height of the second partition member 15b is the maximum length of the second partition member 15b in the third direction Z. This is the maximum length. Moreover, the first embodiment and the third embodiment can also be combined.

When the first partition member 15a and the second partition member 15b are resin members containing light scattering particles, the concentration of the light scattering particles contained in the first partition member 15a is determined by the concentration of the light scattering particles contained in the second partition member 15b. By making the concentration lower than the concentration of , the reflectance of the first partition member 15a can be made lower than the reflectance of the second partition member 15b. In any of the first embodiment, the second embodiment, and the third embodiment, the concentration of light scattering particles contained in the first partition member 15a is lower than the concentration of light scattering particles contained in the second partition member 15b. can do. In a combination of the first embodiment and the second embodiment, the concentration of light scattering particles contained in the first partition member 15a can be lower than the concentration of light scattering particles contained in the second partition member 15b. . In a combination of the first embodiment and the third embodiment, the concentration of light scattering particles contained in the first partition member 15a can be lower than the concentration of light scattering particles contained in the second partition member 15b. .

By making the reflectance of the material (resin, metal, dielectric multilayer film, etc.) of the first partition member 15a lower than the reflectance of the material (resin, metal, dielectric multilayer film, etc.) of the second partition member 15b, , the reflectance of the first partition member 15a can be made lower than the reflectance of the second partition member 15b. In any one of the first embodiment, the second embodiment, and the third embodiment, the reflectance of the material of the first partition member 15a can be made lower than the reflectance of the material of the second partition member 15b. In a combination of the first embodiment and the second embodiment, the reflectance of the material of the first partition member 15a can be made lower than the reflectance of the material of the second partition member 15b. In a combination of the first embodiment and the third embodiment, the reflectance of the material of the first partition member 15a can be made lower than the reflectance of the material of the second partition member 15b.

Further, as shown in FIG. 7, the volume of the first partition member 15a may be smaller than the volume of the second partition member 15b. As a result, the brightness of the first groove 14-1 in a state where only one first outer part 1c is emitted is changed from the brightness of the second groove 14-2 in a state where only one first inner part 1a is emitted. In addition, the amount of light entering the first outer part 1c from the first inner part 1a is increased compared to the case where the volume of the first partition member 15a is the same as the volume of the second partition member 15b. be able to.

[Fourth embodiment]
FIG. 8A is a plan view of the second partition member 15b of the fourth embodiment.
FIG. 8B is a plan view of the first partition member 15a of the fourth embodiment.
FIG. 9 is a cross-sectional view taken along line IX-IX in FIG. 8B.

In the fourth embodiment, the area of the first partition member 15a in plan view is smaller than the area of the second partition member 15b in plan view. In other words, the area in plan view of the light guide member 10 exposed from the first partition member 15a in the first groove 14-1 is the area of the light guide member 10 exposed from the second partition member 15b in the second groove 14-2. It is larger than the area in plan view. As a result, the brightness of the first groove 14-1 in a state where only one first outer part 1c is emitted is changed from the brightness of the second groove 14-2 in a state where only one first inner part 1a is emitted. In addition, the amount of light entering the first outer part 1c from the first inner part 1a is increased compared to the case where the area of the first partition member 15a is the same as the area of the second partition member 15b. be able to.

In the example shown in FIGS. 8B and 9, an opening 16 that exposes the light guide member 10 is formed in the first partition member 15a that covers the side surface of the light emitting part 1. As shown in FIG. 8B, the opening 16 extends continuously in the direction in which the groove 14 extends. Further, the openings 16 may be disposed intermittently in the extending direction of the groove 14. Further, the plurality of openings 16 may be arranged in a dot shape in a plan view. In the example shown in FIG. 8A, an opening that exposes the light guide member 10 is not formed in the second partition member 15b that covers the side surface of the light emitting part. Note that openings may be provided in the first partition member 15a and the second partition member 15b so that the area of the first partition member 15a in plan view is smaller than the area of the second partition member 15b in plan view. .

The fourth embodiment can be combined with at least one of the embodiments described above.

The third groove 14-3 located between the outer parts can have the same configuration as the second groove 14-2. This makes it easier for light to enter from the adjacent outer parts in the outer part, compensates for the decrease in brightness in the area on the outer peripheral side of the light guide member 10 in the fully lit state, and reduces uneven brightness on the light emitting surface of the planar light source. can do.

Furthermore, among the plurality of outer parts, the number of light emitting parts 1 in which one second outer part 1d located at a corner of the light guide member 10 is adjacent to the other is greater than the number of light emitting parts 1 in which one second outer part 1c located at a position other than a corner is adjacent to each other. The number is smaller than the number of adjacent light emitting sections 1. Therefore, in the fully lit state, the brightness of the corners of the light guide member 10 tends to be particularly dark among the outer circumference side regions. Therefore, the brightness of the third groove 14-3 between the first outer part 1c and the second outer part 1d in a state where only one second outer part 1d is emitted is different from that of only one first outer part 1c. It is preferable that the brightness be set to be brighter than the brightness of the first groove 14-1 in the state where the light is emitted. Thereby, it is possible to compensate for the decrease in brightness at the corners of the light guide member 10 in the fully lit state, and further reduce the uneven brightness on the light emitting surface of the planar light source.

For example, the depth from the first surface 11 of the first groove part 14a of the third groove 14-3 between the first outer part 1c and the second outer part 1d is The depth from the first surface 11 can be made shallower than the depth from the first surface 11. In addition, the reflectance of the first partition member 15a disposed in the third groove 14-3 between the first outer part 1c and the second outer part 1d is The reflectance can be lower than that of the member 15a. Furthermore, the area in plan view of the first partition member 15a disposed in the third groove 14-3 between the first outer part 1c and the second outer part 1d is The area can be made smaller than the area of the one-section member 15a in plan view. In addition, the volume of the first partition member 15a arranged in the third groove 14-3 between the first outer part 1c and the second outer part 1d is determined by the volume of the first partition member 15a arranged in the first groove 14-1. The volume can be made smaller than that of 15a.

[Fifth embodiment]
In each of the embodiments described above, by making the brightness of the outer light source 20A itself brighter than the brightness of the inner light source 20A itself, uneven brightness on the light emitting surface of the planar light source in the fully lit state is further reduced. be able to. For example, by making the power supplied to the outer light source 20A higher than the power supplied to the inner light source 20A, the brightness of the outer light source 20A is made brighter than the brightness of the inner light source 20A. be able to. Further, for example, by making the size of the outer light source 20A larger than the size of the inner light source 20A, the brightness of the outer light source 20A can be made brighter than the brightness of the inner light source 20A. can.

[Sixth embodiment]
FIG. 10A is a cross-sectional view of the groove 14 of the sixth embodiment. The groove 14 of the sixth embodiment can be applied to any of the first groove 14-1, second groove 14-2, and third groove 14-3 in each of the embodiments described above. In the sixth embodiment, after forming the groove 14, the light guide member 10 is placed on the support member 50. Note that in FIGS. 10A and 10B, the first partition member 15a and the second partition member 15b are simply referred to as partition member 15 without distinguishing them.

A portion of the light guide member 10 adjacent to the groove 14 has an extended portion 18 . The extending portion 18 extends from a portion of the side surface 17 of the light guide member 10 adjacent to the groove 14 located closer to the second surface 12 than the first surface 11 toward the adjacent light guide member 10 . The extending portions 18 of adjacent light guide members 10 face each other.

The extending portion 18 has an inner surface 18a that faces the side surface 17 and is continuous with the side surface 17. The partition member 15 is arranged on the side surface 17 and the inner surface 18a. The partition member 15 disposed on the inner surface 18a of the extension part 18 makes it easier to suppress light guide between adjacent light emitting parts 1 during local dimming, and makes it easier to control the brightness of each light emitting part 1.

By making the extension length of the extension part 18 of the first groove 14-1 shorter than the extension length of the extension part 18 of the second groove 14-2, the 1. To increase the amount of light directed toward the outer portion 1c than when the length of the extending portion 18 of the first groove 14-1 is the same as that of the extending portion 18 of the second groove 14-2. I can do it. Further, the extended length of the extended portion 18 of the third groove 14-3 between the first outer portion 1c and the second outer portion 1d is made shorter than the extended length of the extended portion 18 of the first groove 14-1. By doing so, the brightness of the corners of the light guide member 10 can be improved.

In a cross-sectional view, a part of the outer edge of the extending portion 18 may be a straight line, a curved line, or may have unevenness. For example, as shown in FIG. 10B, the distal end portion of the extending portion 18 may have a plurality of convex portions 19. By covering the convex portion 19 of the extending portion 18 with the partitioning member 15, the area in which the extending portion 18 and the partitioning member 15 are in contact can be increased. Thereby, the adhesion between the extending portion 18 and the partitioning member 15 can be improved. Note that the extending portion 18 may have one convex portion. Further, as shown in FIG. 10B, at least a portion of the lower surface of the extending portion 18 is preferably a curved line in a cross-sectional view. For example, even if an external force is applied to the extending portion 18 when placing the light guide member 10 on the supporting member 50, the lower surface of the extending portion 18 is can suppress chipping.

The embodiments of the present invention have been described above with reference to specific examples. However, the present invention
It is not limited to these specific examples. All forms that can be implemented by appropriately modifying the design based on the above-described embodiments of the present invention by those skilled in the art also belong to the scope of the present invention as long as they encompass the gist of the present invention. In addition, those skilled in the art will be able to come up with various changes and modifications within the scope of the present invention, and these changes and modifications also fall within the scope of the present invention.

DESCRIPTION OF SYMBOLS 1... Light emitting part, 1a... First inner part, 1b... Second inner part, 1c... First outer part, 1d... Second outer part, 10... Light guide member, 14... Groove, 14-1... First groove , 14-2... Second groove, 14-3... Third groove, 15a... First partition member, 15b... Second partition member, 20A to 20C... Light source, 21... Light emitting element, 30... First translucent member , 40...first light reflecting member, 50...supporting member

Claims (6)

a light guide member having a plurality of light emitting parts separated by grooves;
a light source disposed in each of the plurality of light emitting units;
Equipped with
The plurality of light emitting parts include a plurality of outer parts including a first outer part, and a first inner part adjacent to the first outer part and located in a region surrounded by the plurality of outer parts in plan view. , a plurality of inner parts including a second inner part adjacent to the first inner part,
In plan view, each of the plurality of outer parts is adjacent to a smaller number of light emitting parts than the number of light emitting parts adjacent to one of the inner parts,
The groove includes a first groove located between the first outer part and the first inner part, and a second groove located between the first inner part and the second inner part. death,
A planar light source wherein the brightness of the first groove in a state in which only the first outer part is emitted is brighter than the brightness in the second groove in a state in which only the first inner part is emitted. The planar light source according to claim 1, further comprising: a first partition member disposed within the first groove; and a second partition member disposed within the second groove. The planar light source according to claim 2, wherein the first partition member has a lower reflectance than the second partition member. The planar light source according to claim 2 or 3, wherein the first partition member is thinner than the second partition member. 5. The planar light source according to claim 2, wherein the area of the first partition member in plan view is smaller than the area of the second partition member in plan view. The planar light source according to claim 2, wherein the volume of the first partition member is smaller than the volume of the second partition member.

Images