JPWO2015033847A1 - Planar light emitting unit - Google Patents

Abstract

The planar light-emitting panel (10) of the planar light-emitting unit has a light source luminance distribution in which the front luminance at the peripheral portion is higher than the luminance at the central portion of the light emitting area (LA). 31) has a light transmittance distribution in which the transmittance is higher in the region facing the non-light emitting region (NLA) than in the region facing the central portion of the light emitting region (LA).

Description

  The present invention relates to a structure of a planar light emitting unit using a planar light emitting panel.

  2. Description of the Related Art In recent years, light emitting devices with high light emission efficiency using surface light emitting elements such as organic EL panels (Organic Electroluminescence Panel) have attracted attention. Such a light-emitting device is not limited to the lighting field, and is also used as a backlight of various electronic devices such as a liquid crystal television, a computer monitor, or an outdoor advertisement.

  In JP 2012-163785 A (Patent Document 1), by stacking an optical sheet according to the LED light source luminance in a direct-type LED backlight illumination, and changing the transmittance of the optical sheet between the center and the periphery A technique for obtaining a uniform light source is disclosed.

JP 2012-163785 A

  In the light emission luminance distribution of the planar light emitting panel, it is known that a non-light emitting region is formed in the peripheral portion of the planar light emitting panel. Therefore, in a planar light emitting unit in which a plurality of planar light emitting panels are arranged vertically and horizontally and used as a large light source, there is a problem that luminance unevenness due to a non-light emitting region occurs on the light emitting surface of the planar light emitting unit.

  The present invention has been made in view of the above problems, and a planar light emitting unit capable of suppressing occurrence of luminance unevenness due to a non-light emitting area of a planar light emitting panel on a light emitting surface of the planar light emitting unit. The purpose is to provide.

  In the planar light emitting unit according to one aspect of the present invention, a planar light emitting panel including a light emitting region and a non-light emitting region provided around the light emitting region, and a light emitting surface of the planar light emitting panel are spaced apart from each other. An optical filter disposed; and a light diffusing member disposed on the opposite side of the planar light emitting panel of the optical filter.

  At least two or more of the planar light emitting panels are arranged with respect to the optical filter, and the planar light emitting panel has a front surface in the peripheral portion rather than a front luminance in the center of the light emitting region within the surface. The optical filter has a light source luminance distribution in which luminance is increased, and the optical filter has a light transmittance that is higher in a region facing the non-light emitting region than in a region facing the central portion of the light emitting region. It has a transmittance distribution.

It is a top view which shows the basic composition of the planar light emission panel in embodiment. It is the II-II arrow directional cross-sectional view in FIG. It is a partial exploded perspective view which shows the basic composition of the planar light emission panel in embodiment. It is sectional drawing which shows schematic structure of the planar light emission unit in embodiment. It is a figure which shows the light source luminance distribution of the planar light emission panel in Examples 1-3 and a comparative example. It is a figure which shows the aperture density distribution of the optical filter in Examples 1 to 3 and a comparative example. It is a figure which shows the front luminance distribution of the planar light emission unit in Examples 1-3 and a comparative example. It is a conceptual partial enlarged view which shows the aperture density distribution of the optical filter in Examples 1-3 and a comparative example.

  Hereinafter, a planar light emitting panel and a planar light emitting unit using the planar light emitting panel in each embodiment based on the present invention will be described with reference to the drawings. In the embodiments described below, when referring to the number, amount, and the like, the scope of the present invention is not necessarily limited to the number, amount, and the like unless otherwise specified. The same parts and corresponding parts are denoted by the same reference numerals, and redundant description may not be repeated. It is planned from the beginning to use a combination of the configurations in each embodiment as appropriate.

(Surface emitting panel 10)
With reference to FIG. 1 and FIG. 2, the basic structure of the planar light-emitting panel 10 in the present embodiment will be described. FIG. 1 is a front view showing the planar light emitting panel 10 and shows a state when the planar light emitting panel 10 is viewed from the back surface 19 side of the planar light emitting panel 10. 2 is a cross-sectional view taken along line II-II in FIG.

  The planar light emitting panel 10 in the present embodiment is composed of an organic EL. The planar light emitting panel 10 may be configured as a planar light emitting panel from a plurality of light emitting diodes (LEDs) and a diffusion plate, or may be configured as a planar light emitting panel using a cold cathode tube or the like. .

  1 and 2, a planar light emitting panel 10 includes a transparent substrate 11 (cover layer), an anode (anode) 14, an organic layer 15, a cathode (cathode) 16, a sealing member 17 and an insulating layer 18. Including. The planar light emitting device 1 is constituted by the anode 14, the organic layer 15, and the cathode 16.

  The transparent substrate 11 forms the surface 12 of the planar light emitting panel 10, that is, the light extraction surface (light emitting surface), and the outer peripheral end surface of the transparent substrate 11 forms the outer periphery 10 E of the planar light emitting panel 10. The anode (electrode layer) 14, the organic layer 15, and the cathode (electrode layer) 16 are sequentially stacked on the back surface 13 of the transparent substrate 11. The sealing member 17 forms the back surface 19 of the planar light emitting panel 10.

  As a member constituting the transparent substrate 11, a light transmissive film substrate such as polyethylene terephthalate (PET) or polycarbonate (PC) is used. Various glass substrates may be used for the transparent substrate 11.

  In addition, polyimide, polyethylene naphthalate (PEN), polystyrene (PS), polyethersulfone (PES), polypropylene (PP), etc. are used as the light transmissive film substrate.

  The anode 14 is a conductive film having transparency, and constitutes a transparent electrode. In order to form the anode 14, ITO (Indium Tin Oxide) or the like is formed on the transparent substrate 11 by sputtering or the like. As another material used for the anode 14, polyethylenedioxythiophene (PEDOT) is used.

  The organic layer 15 forming the light emitting layer (light emitting portion) can generate light (visible light) by being supplied with electric power. The organic layer 15 may be composed of a single light emitting layer, or may be composed of a hole transport layer, a light emitting layer, a hole blocking layer, an electron transport layer, and the like that are sequentially laminated. A light emitting region LA is formed by the generation of light by the organic layer 15.

  The cathode 16 is, for example, aluminum (Al). The cathode 16 is formed so as to cover the organic layer 15 by a vacuum deposition method or the like. In order to pattern the cathode 16 into a predetermined shape, a mask may be used during vacuum deposition. Other materials for the cathode 16 include lithium fluoride (LiF), a stack of Al and Ca, a stack of Al and LiF, a stack of Al and Ba, and the like.

  An insulating layer 18 is provided between the cathode 16 and the anode 14 so that the cathode 16 and the anode 14 are not short-circuited. The insulating layer 18 is formed in a desired pattern so as to cover a portion that insulates the anode 14 and the cathode 16 from each other using a photolithography method or the like after, for example, a SiO 2 film is formed using a sputtering method.

  The sealing member 17 is made of an insulating resin or glass substrate. The sealing member 17 is formed to protect the organic layer 15 from moisture and the like. The sealing member 17 seals substantially the whole of the anode 14, the organic layer 15, and the cathode 16 (member provided inside the planar light emitting panel 10) on the transparent substrate 11. A part of the anode 14 is exposed from the sealing member 17 for electrical connection.

The sealing member 17 is formed by laminating a plurality of layers of inorganic thin films such as SiO ₂ , Al ₂ O ₃ , SiNx, and flexible acrylic resin thin films on a film such as PET, PEN, PS, PES, and polyimide. Thus, those having gas barrier properties are used. Gold, silver, copper, or the like may be further laminated on the electrode portion 21 and the electrode portion 22.

  A portion (left side in FIG. 2) exposed from the sealing member 17 of the anode 14 constitutes an electrode portion 21 (for anode). The electrode portion 21 and the anode 14 are made of the same material. As shown in FIG. 3, the electrode portion 21 is provided so as to surround a pair of corner portions of the anode 14 and is located on the outer periphery of the planar light emitting panel 10. The electrode portion 21 is set to a length exceeding half of one side of the rectangular anode 14.

  The organic layer 15 and the anode 14 side have a large contact area, and the anode 14 is formed to be thin so as to transmit light, and thus has a certain electric resistance. Therefore, a voltage drop occurs in the central portion of the anode 14 by supplying power from the peripheral portion. By using this voltage drop, it is possible to provide a light source luminance distribution in which the peripheral front luminance is stronger than the central front luminance of the light emitting area LA.

  The portion of the cathode 16 exposed from the sealing member 17 (on the right side in FIG. 2) constitutes an electrode portion 22 (for the cathode). The electrode part 22 and the cathode 16 are made of the same material. As shown in FIG. 3, the electrode portion 22 is provided at a pair of corner portions different from the pair of corner portions of the anode 14, and is located on the outer periphery of the planar light emitting panel 10.

  The electrode part 21 and the electrode part 22 are located on opposite sides of the organic layer 15. A divided region 20 (see FIG. 1) is formed between adjacent electrode portions 21 and electrode portions 22. A wiring pattern (not shown) is attached to the electrode portion 21 and the electrode portion 22 using soldering (silver paste) or the like. As understood from the drawing, when the electrode portion 22 of the cathode 16 and the electrode portion 21 of the anode 14 are compared, the region exposed from the sealing member 17 is larger in the latter case. In other words, the electrode portion 21 of the anode 14 is formed on the outer periphery of the planar light emitting panel 10 so as to surround the light emitting area LA.

  Electric power is supplied to the organic layer 15 of the planar light emitting panel 10 configured as described above from an external power supply device through wiring patterns (not shown), the electrode portions 21 and 22, the anode 14, and the cathode 16. The light generated in the organic layer 15 is extracted from the surface 12 (light emitting surface) to the outside through the anode 14 and the transparent substrate 11.

  On the surface 12, a region substantially corresponding to the organic layer 15 constitutes a light emitting region LA that emits light, and a peripheral region surrounding the light emitting region LA is a non-light emitting region NLA. In the present embodiment, the transparent substrate 11 has an outer size of 100 mm × 100 mm, and the light emitting area LA is 90 mm × 90 mm. Therefore, the non-light emitting area NLA is provided around the light emitting area LA and has a width of 5 mm.

(Surface emitting unit 100)
Next, with reference to FIG. 4, a schematic configuration of the planar light emitting unit 100 using the planar light emitting panel 10 having the above configuration will be described. FIG. 4 is a cross-sectional view illustrating a schematic configuration of the planar light emitting unit 100.

  The planar light emitting unit 100 uses two planar light emitting panels 10. There is no limitation on the number of sheets, and it is preferable to use the number of sheets as necessary. In the present embodiment, the two planar light emitting panels 10 are arranged such that the outer peripheries 10E (see FIG. 2) of the transparent substrate 11 are substantially in contact with each other. Therefore, a non-light emitting area NLA having a width C (about 10 mm) is formed between the light emitting areas LA.

  On the light emitting surface 12 side of the planar light emitting panel 10, an optical filter 31 is arranged in parallel to the light emitting surface 12 with a predetermined gap (b: about 10 mm) from the light emitting surface 12. The optical filter 31 is in close contact with a transparent acrylic plate 32 having a thickness of about 3 mm.

  The optical filter 31 is printed with a pattern having an opening having a circular light transmission region using inkjet. This pattern adjusts the transmittance of the optical filter 31. The diameter of the opening is, for example, φ0.1 mm and φ0.3 mm. The aperture density of the optical filter 31 is set by appropriately combining these apertures.

  When creating an aperture ratio distribution of the optical filter 31 with a constant aperture size, the aperture size (in this embodiment, 1/300 or less) with respect to the light source size (in this embodiment, 90 mm × 90 mm). 0.3 mm or less) is preferable. This is because a difference in opening efficiency is easily obtained. Preferably, it is 1/900 of the light source size (in this embodiment, 0.1 mm or less). This is because when the light emitting surface of the planar light emitting unit 100 is enlarged, the opening is difficult to recognize when the light emitting surface (screen) is observed from an overhead view, and the design is not impaired.

  On the opposite side of the optical filter 31 from the planar light emitting panel 10, a light diffusion plate 30 is disposed in parallel to the light emitting surface 12 with a predetermined gap (a) with respect to the light emitting surface 12. The light diffusion plate 30 has air interposed between the acrylic plate 32. A gap (d) is formed between the optical filter 31 and the light diffusion plate 30.

  For the light diffusing plate 30 as a light diffusing member, a light diffusing agent (fine particles for light diffusing) having a desired value in particle diameter, particle size distribution, refractive index and the like is selected, and the light diffusing is carried out in a substrate such as polycarbonate resin. It can be produced by dispersing the material. The light diffusing member is not limited to the light diffusing plate, and a light diffusing sheet, a light transmitting / diffusing optical filter, a light guide plate, or the like can be suitably used. As the light diffusion member, a transparent substrate having a microlens array (unevenness) surface shape may be used.

  Preferably, a highly reflective member or the like is disposed in the space between the optical filter 31 and the planar light emitting panel 10 in the non-light emitting area NLA, and the reflected light from the optical filter 31 to the planar light emitting panel 10 is not emitted. The reflected light may be reused by reflecting it in the region NLA.

(Example)
Next, referring to FIG. 5 to FIG. 8, the light source luminance distribution of the planar light-emitting panel 10, the aperture density distribution of the optical filter 31, and the planar light-emitting unit in each example and comparative example of the present embodiment. The front luminance distribution of 100 will be described. The configuration of the planar light emitting unit 100 is the configuration shown in FIG.

  FIG. 5 is a diagram showing the light source luminance distribution of the planar light emitting panel 10 in Examples 1 to 3 and the comparative example, and FIG. 6 is a diagram showing the aperture density distribution of the optical filter 31 in Examples 1 to 3 and the comparative example. 7 is a diagram showing the front luminance distribution of the planar light emitting units 100 in Examples 1 to 3 and the comparative example, and FIG. 8 is a conceptual partial enlargement showing the aperture density distribution of the optical filter in Examples 1 to 3 and the comparative example. FIG.

  In the planar light emitting unit 100 of the present example and the comparative example, the optical filter 31 and the light diffusion plate 30 are configured to be formed on each surface of a transparent acrylic plate 32. The acrylic plate 32 has a thickness of 3 mm (see FIG. 4). The planar light emitting panel 10 used in the present example and the comparative example is a white light source.

  On the optical filter 31, an opening pattern for adjusting the light transmittance is drawn by an ink jet method using white ink. The optical filter 31 is in close contact with the acrylic plate 32. The light diffusing plate 30 is attached to the acrylic plate 32 with air interposed on the surface of the acrylic plate 32.

  Thus, when the planar light emission panel 10 is comprised with a white light source, it is preferable that the optical filter 31 is implement | achieved by the white opening pattern. By using the same white color as that of the light source, absorption of light from the light source can be suppressed and light utilization efficiency can be increased. The optical filter 31 may have a function of scattering light.

  As shown in FIG. 8, the optical filter 31 includes a light transmission member 31p and a white pattern 31s having a plurality of openings provided on the surface of the light transmission member 31p. Adjustment of the aperture ratio distribution of the optical filter 31 is performed by adjusting the arrangement position and size (opening diameter) of the plurality of openings 31d.

  As shown in FIG. 8, the opening density of the opening 31d in the region 31x shows a distribution larger than the opening density of the opening 31d in the region 31y. As the opening diameter of the opening 31d, φ0.9 mm, φ0.3 mm, φ0.01 mm, or the like is used.

  When creating an opening in the optical filter with a constant opening diameter, the opening diameter may be configured to be 1/100 or less of the light source size. In the case of the present embodiment, 90 mm / 100 = φ0.9 mm. In the case of φ0.9 mm, it becomes easy to make a difference in aperture density. Preferably, it is 1/1000 with respect to the light source size. In the case of the present embodiment, 90 mm / 1000 = φ0.09 mm. In the case of φ0.09 mm, when the light emitting surface of the planar light emitting unit is enlarged, it is difficult to recognize the opening even if the light emitting surface is viewed from above.

(Comparative example)
As shown in the light source luminance distribution of FIG. 5, the planar light emitting panel 10 used in the comparative example has a Lambertian light distribution source distributed on the light source surface so that the front luminance is uniform. The optical filter 31 has an aperture density adjusted by an aperture density distribution as shown in FIG. 6 using a white ink (white film) with a transmittance of 66% and an aperture diameter of 0.3 mm.

  As shown in FIG. 7, the front luminance distribution on the light emitting surface of the planar light emitting unit 100 in the comparative example is a region corresponding to the non-light emitting region generated between the two planar light emitting panels 10 arranged, and the luminance decreases. Can be confirmed.

(Example 1: 5% luminance distribution)
The planar light emitting unit 100 according to the first embodiment uses the planar light emitting panel 10 shown in FIGS. 1 to 4 with an increased amount of power supplied from the peripheral portion. The planar light-emitting panel 10 is a surface-emitting light source that brightens in a peripheral portion with good electron and hole injection properties. FIG. 5 shows the light source luminance distribution of Example 1 as the light source distribution. The peripheral portion is configured to have a brightness 5% higher than that of the central portion.

  The optical filter 31 used in Example 1 is the same as the comparative example as shown in the optical filter aperture density distribution of FIG. The acrylic plate 32 is the same as that of the comparative example.

  The planar light-emitting panel 10 used in the planar light-emitting unit 100 of Example 1 has a light source luminance distribution in which the peripheral front luminance is stronger than the central front luminance in the light-emitting area LA, and the optical filter 31 is used. Has an aperture density distribution in which the aperture density is higher in the region facing the non-light emitting region NLA than in the region facing the central portion of the light emitting region LA.

  As a result, as shown in FIG. 7, the front luminance distribution on the light emitting surface of the planar light emitting unit 100 in Example 1 is a region corresponding to the non-light emitting region generated between the two planar light emitting panels 10 arranged. It can be confirmed that the luminance is greatly improved as compared with the comparative example, and the occurrence of luminance unevenness is reduced.

(Example 2: 20% luminance distribution)
The planar light emitting unit 100 in Example 2 uses the planar light emitting panel 10 shown in FIGS. 1 to 4 with an increased amount of power supplied from the periphery. The planar light-emitting panel 10 is a surface-emitting light source that brightens in a peripheral portion with good electron and hole injection properties. In FIG. 5, the light source luminance distribution of Example 2 is shown. The peripheral portion is configured to have 20% higher luminance than the central portion.

  The optical filter 31 used in Example 2 is the same as the comparative example as shown in the optical filter aperture density distribution of FIG. The acrylic plate 32 is the same as that of the comparative example.

  The planar light-emitting panel 10 used in the planar light-emitting unit 100 of Example 2 has a light source luminance distribution in which the front luminance of the peripheral portion is higher than the central front luminance of the light emitting area LA. Has an aperture density distribution in which the aperture density is higher in the region facing the non-light emitting region NLA than in the region facing the central portion of the light emitting region LA.

  As a result, as shown in FIG. 7, the front luminance distribution on the light emitting surface of the planar light emitting unit 100 in Example 2 is an area corresponding to the non-light emitting area generated between the two planar light emitting panels 10 arranged. Compared to Example 1, it can be confirmed that the luminance is further improved and the occurrence of luminance unevenness is reduced.

(Example 3: 20% luminance distribution, φ0.1 mm)
The planar light emitting unit 100 in Example 3 uses the planar light emitting panel 10 shown in FIGS. 1 to 4 with an increased amount of power supplied from the peripheral portion. The planar light-emitting panel 10 is a surface-emitting light source that brightens in a peripheral portion with good electron and hole injection properties. FIG. 5 shows the light source luminance distribution of Example 3 as the light source distribution. Similar to the second embodiment, the peripheral portion is configured to have 20% higher luminance than the central portion.

  The optical filter 31 used in Example 3 has an aperture diameter of φ0.1 mm, and has an optical filter aperture density that is higher than the optical luminance of Example 1 as shown in FIG. As the aperture size is reduced, fine brightness correction is possible.

  In the planar light emitting unit 100 according to the third embodiment, the planar light emitting panel 10 has a light source luminance distribution in which the peripheral front luminance is stronger than the central front luminance in the light emitting area LA. Has an aperture density distribution in which the aperture density is higher in the region facing the non-light emitting region NLA than in the region facing the central portion of the light emitting region LA.

  As a result, as shown in FIG. 7, the luminance is higher in the region corresponding to the non-light emitting region generated between the two planar light emitting panels 10 arranged as compared with the first embodiment. In comparison, the brightness is reduced.

  However, as compared with Example 2, overall brightness in Example 3 changes gradually, particularly in the vicinity of the non-light-emitting region generated between the planar light-emitting panels 10. No. 3 has a smoother luminance distribution, and the luminance difference between the non-light emitting region and the vicinity thereof is smaller. This means that the difference between light and dark is small, and Example 3 is superior to Example 2 in terms of uniform light emission on the light emitting surface.

  As described above, according to the planar light emitting unit 100 in the present embodiment, the peripheral front brightness of the surface light source is made stronger than the central front brightness of the surface light source, and the center of the surface light source is corrected by the optical filter. And the occurrence of uneven brightness in the periphery. Further, the light returned to the light source side by the optical filter corresponding to the peripheral portion can be efficiently guided to the non-light emitting portion, and the luminance of the light emitting surface corresponding to the non-light emitting region of the planar light emitting unit 100 can be increased. .

  Furthermore, the aperture density of the optical filter is made higher at the non-light emitting portion than at the light source central portion, so that the luminance of the non-light emitting portion remains as it is and the luminance of the light source central portion is suppressed, so that the luminance of the entire surface light emitting unit is reduced. A large surface light source with less unevenness can be configured.

  In the present embodiment, the method for adjusting the aperture density has been described as one method for adjusting the light transmittance of the optical filter 31, but the method is not limited to this method. For example, as another method of adjusting the light transmittance of the optical filter 31, there is a method of changing the density of the pattern itself. As a method of adjusting the light transmittance distribution in this case, the same pattern is used for the whole, the pattern density is lightened in the region where the light transmittance is desired to be increased, and the pattern density is increased in the region where the light transmittance is desired to be lowered. Thus, the light transmittance of the optical filter 31 can be adjusted. Further, in addition to the adjustment of the density of the pattern itself, the arrangement position and size of the light transmission region may be further adjusted in the same manner as the opening pattern described above.

  In the planar light emitting unit described above, a planar light emitting panel including a light emitting region and a non-light emitting region provided around the light emitting region, and a light emitting surface of the planar light emitting panel are disposed with a gap therebetween. An optical filter; and a light diffusing member disposed on the opposite side of the optical filter from the planar light emitting panel.

  At least two or more of the planar light emitting panels are arranged with respect to the optical filter, and the planar light emitting panel has a front surface in the peripheral portion rather than a front luminance in the center of the light emitting region within the surface. The optical filter has a light source luminance distribution in which luminance is increased, and the optical filter has a light transmittance that is higher in a region facing the non-light emitting region than in a region facing the central portion of the light emitting region. It has a transmittance distribution.

  For example, the planar light-emitting panel includes a light-emitting layer, a pair of electrode layers sandwiching the light-emitting layer from both sides, and an electrode portion connected to each electrode layer for supplying power to the pair of electrode layers. I have. And among the electrode layers, the light extraction surface side of the planar light emitting panel, that is, the light emitting surface side is constituted by a transparent electrode layer, and the electrode portion connected to the transparent electrode layer is the light emitting region on the outer periphery of the planar light emitting panel. It is formed so as to surround.

  In another embodiment, the optical filter includes a light transmissive member and a pattern having a plurality of light transmissive regions formed on the surface of the light transmissive member, and adjustment of the light transmittance distribution of the optical filter is performed. This is done by adjusting the arrangement position and size of the plurality of light transmission regions.

  In another embodiment, the planar light emitting panel is a white light source, and the pattern is formed using a white material.

  By adopting the above configuration, it is possible to provide a planar light emitting unit that can suppress the occurrence of luminance unevenness due to the non-light emitting area of the planar light emitting panel on the light emitting surface of the planar light emitting unit.

  The planar light emitting unit in each embodiment of the present invention has been described above, but the embodiment disclosed this time should be considered as illustrative in all points and not restrictive. Therefore, the scope of the present invention is defined by the terms of the claims, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  DESCRIPTION OF SYMBOLS 1 Planar light emitting element, 10 Planar light emitting panel, 10E outer periphery, 11 Transparent substrate, 12 Surface, 13 Back surface, 14 Anode, 15 Organic layer, 16 Cathode, 17 Sealing member, 18 Insulating layer, 19 Back surface, 30 Light diffusion Plate, 31 Optical filter, 31s, 31t region, 31d Opening, 31s pattern, 31p Light transmissive member.

Claims (4)

A planar light emitting panel including a light emitting region and a non-light emitting region provided around the light emitting region;
An optical filter disposed with a gap with respect to the light emitting surface of the planar light emitting panel;
A light diffusing member disposed on the opposite side of the planar light emitting panel of the optical filter;
With
Arranged such that at least two or more planar light emitting panels are arranged with respect to the optical filter,
The planar light emitting panel has a light source luminance distribution in which the peripheral front luminance is stronger than the central front luminance of the light emitting area in the plane,
In the surface, the optical filter has a light transmittance distribution in which the transmittance of the region facing the non-light emitting region is higher than the region facing the central portion of the light emitting region. The planar light emitting panel is
A light emitting layer;
A pair of electrode layers sandwiching the light emitting layer from both sides;
An electrode portion connected to each electrode layer for supplying power to the pair of electrode layers;
With
Among the electrode layers, the light extraction surface side of the planar light emitting panel is formed of a transparent electrode layer, and the electrode portion connected to the transparent electrode layer is formed so as to surround the light emitting region on the outer periphery of the planar light emitting panel. The planar light-emitting unit according to claim 1. The optical filter is
A light transmissive member;
A pattern having a plurality of light transmission regions formed on the surface of the light transmission member;
3. The planar light emitting unit according to claim 1, wherein the light transmittance distribution of the optical filter is adjusted by adjusting an arrangement position and a size of the plurality of light transmitting regions.   The planar light emitting unit according to claim 3, wherein the planar light emitting panel is a white light source, and the pattern is formed using a white material.

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