JPWO2013124953A1 - Light emitting device - Google Patents

Abstract

An object of the present invention is to provide a light emitting device capable of emitting end face light with high luminance from the entire peripheral end surface of the light emitting device. [Structure] A light transmission layer is formed so as to cover the planar light emitting region of the organic EL light emitting panel, and an opaque light reflection layer is provided on the surface of the light transmission layer. [Selection] Figure 2

Description

  The present invention relates to a light emitting device, and more particularly to a light emitting device using a light emitting panel having a planar light emitting region.

  Currently, an organic electroluminescent light emitting panel (hereinafter referred to as an organic EL light emitting panel) is known as a light emitting panel having a planar light emitting region. Although the organic EL light-emitting panel can perform toning and light control by full-color light emission, the light emission luminance per unit area is lower than that of a fluorescent lamp or LED illumination. Therefore, for example, in the case of performing so-called end surface light emission in which light emission is performed in a band-like narrow light emission region, there is a problem that sufficient brightness cannot be obtained.

  Therefore, an optical waveguide layer made of silicon oxide having a thickness of about 1.0 μm is provided on the light emitting surface of the EL light emitting panel, and light emitted from the light emitting surface of the EL light emitting panel is propagated in the optical waveguide layer to There has been proposed an edge-emitting EL device that obtains high-luminance edge light by being concentrated and led to the edge face side (see Patent Document 1).

  However, the obtained end face light is line light concentrated in a specific direction, and the end face light cannot be emitted to the entire periphery of the light emitting device. In addition, part of the light emitted from the light emitting surface of the EL light emitting panel passes through this optical waveguide layer and leaks to the front side of the panel, so that the brightness of the light emitted from the panel end surface side can be sufficiently increased. The problem of being unable to do so was given as an example.

Japanese Patent Laid-Open No. 03-138893

  The present invention has been made in view of the above points, and an object of the present invention is to provide a light emitting device capable of emitting edge light with high luminance from the end surfaces around the entire periphery of the light emitting device.

  The light-emitting device according to claim 1 is a light-emitting device including an organic electroluminescence (hereinafter referred to as organic EL) light-emitting panel, and is formed so as to cover a planar light-emitting region of the organic EL light-emitting panel. And a light reflection layer formed on the surface of the light transmission layer.

It is the perspective view which looked at the light-emitting device 10 which concerns on this invention from diagonally upper side. It is sectional drawing which shows the cross section of the light-emitting device 10 in the WW line shown by FIG. 2 is a diagram showing a light emission form by the light emitting device 10. It is a perspective view which shows an example of the form at the time of constructing the light-emitting device 10 as a table. It is a perspective view which shows another example of the form at the time of constructing the light-emitting device 10 as a table. It is a figure which shows an example of the form at the time of using the light-emitting device 10 as a vehicle interior lamp. FIG. 6 is a cross-sectional view illustrating a modification of the light emitting device 10.

  In the light emitting device according to the present invention, a light transmission layer (4) is formed so as to cover the planar light emitting region of the organic EL light emission panel (3), and an opaque light reflection layer (4) is formed on the surface of the light transmission layer (4). 5) is provided. With this configuration, the light emitted from the planar light emitting region of the organic EL light emitting panel propagates through the light transmitting layer while being reflected by the light reflecting layer, and is led to the end surface of the light transmitting layer. Therefore, the light intensity per unit area of the end face light radiated from this end face is higher than the light intensity per unit area in the planar light emitting region of the organic EL light emitting panel. This opaque light reflecting layer is formed by plating, evaporating or bonding a metal foil such as aluminum or silver. At this time, in the light emitting device according to the present invention, the light reflecting layer is provided to prevent light propagating in the light transmitting layer from leaking to the outside of the light transmitting layer. Can be obtained.

  FIG. 1 is a perspective view of a light emitting device 10 according to the present invention as viewed obliquely from above, and FIG. 2 is a cross-sectional view showing a cross section taken along line WW shown in FIG.

  The light emitting device 10 has a plate shape as shown in FIG. 1, and emits end face light as indirect light from the end face (area shown by hatching) of the entire periphery. The indirect light is light that is emitted from the light source to the outside once through the reflector. In the example shown in FIG. 1, the light emitting device 10 has a rectangular plate shape, but may be an N-gon (N is an integer of 3 or more) or a circular plate shape.

  As shown in FIG. 2, the light emitting device 10 has a structure in which an organic EL light emitting panel 3, a light transmission layer 4, and a light reflection layer 5 are laminated between plate-like protective layers 1 and 2.

  The organic EL light-emitting panel 3 is formed on a plate-like organic light-emitting layer 31, a plate-like cathode electrode 32 formed on one surface of both surfaces of the organic light-emitting layer 31, and the other surface. And a plate-like anode electrode 33. At this time, a two-dimensional region where the organic light emitting layer 31 and the cathode electrode 32 overlap on the surface of the anode electrode 33 becomes a planar light emitting region, that is, a light emitting surface in the organic EL light emitting panel 3. A protective layer 2 is formed on the surface of the cathode electrode 32. The anode electrode 33 is a transparent electrode made of, for example, ITO (Indium-tin-oxide), and the light transmission layer 4 having a layer thickness Q made of glass or a transparent resin material is formed on the anode electrode 33. That is, the light transmission layer 4 is formed so as to cover the planar light emitting region of the organic EL light emitting panel 3. Each end face HE of the four sides of the light transmission layer 4 is a radiation area of the end face light by the light emitting device 10, and is exposed to the outside as shown in FIG. Note that the layer thickness Q of the light transmission layer 4 is larger than the layer thickness of the organic EL light-emitting panel 3, and high-luminance edge light can be obtained, for example, by setting it to 5 mm or more.

  On the light transmission layer 4, an opaque light reflection layer 5 is formed that reflects light emitted from the planar light emitting region of the organic EL light emitting panel 3 toward the organic EL light emitting panel 3. At this time, one of the two surfaces of the light reflecting layer 5 is a mirror surface 5a, and the light transmitting layer 4 is bonded thereto as shown in FIG. A protective layer 1 is formed on the other surface of the light reflecting layer 5. The light reflecting layer 5 may be a layer made of an opaque material exhibiting a bright color such as white.

  Here, as shown in FIG. 3A, when the DC power source 8 is connected between the cathode electrode 32 and the anode electrode 33 of the organic EL light emitting panel 3, the organic light emitting layer 31 emits light and is emitted from the planar light emitting region. Light passes through the anode electrode 33 and reaches the light transmission layer 4. At this time, the organic EL light-emitting panel 3 emits soft diffused light over a wide range by emitting light in the entire planar light emitting region, so that the light reaching the light transmission layer 4 is indicated by a thick line arrow in FIG. As described above, the light propagates in the light transmitting layer 4 toward the respective end faces HE on the four sides of the light transmitting layer 4 while being reflected by the mirror surface 5a of the light reflecting layer 5, and is emitted from the end face HE to the outside. That is, as indicated by the black arrow in FIG. 3B, end face light as indirect light is radiated from each of the end faces TS of the four sides of the light emitting device 10 having a rectangular plate shape.

  At this time, in the light emitting device 10, the light emitted from the planar light emitting region of the organic EL light emitting panel 3 is led to the end surface HE of the light transmitting layer 4 narrower than the planar light emitting region through the light transmitting layer 4. I am doing so. Therefore, the light intensity per unit area emitted from the end face HE is higher than the light intensity per unit area in the planar light emitting region of the organic EL light emitting panel 3. That is, end face light having a radiance higher than the radiance in the surface emission emitted from the organic EL light emitting panel 3 used as the light source is emitted from the end face HE.

  Furthermore, in this light emitting device 10, in order to change the traveling direction to the end face HE side without reducing the intensity of the light emitted from the planar light emitting region of the organic EL light emitting panel 3, A light reflecting layer 5 that reflects light toward the organic EL light emitting panel 3 is provided on the surface, that is, the surface facing the surface of the organic EL light emitting panel 3. Thereby, since the light emitted from the planar light emitting region of the organic EL light emitting panel 3 does not leak to the protective layer 1 side, the light emitted from the planar light emitting region is efficiently propagated to the end surface HE side. High radiance can be obtained.

  Here, it is also possible to construct a table using the light emitting device 10 described above.

  FIG. 4 is a perspective view showing an example of a configuration in which the light emitting device 10 according to the present invention is configured as a table.

  As shown in FIG. 4, when the light emitting device 10 is used as a table, the table leg 20 is coupled to the protective layer 2 and the protective layer 1 is used as a table top plate. Therefore, as a material of the protective layer 1, a material generally used as a table top plate, for example, wood, glass, metal or the like is adopted. Further, the DC power source 8 connected to the cathode electrode 32 and the anode electrode 33 of the organic EL light emitting panel 3 is mounted on the surface of the protective layer 2 or inside the leg portion 20.

  As described above, according to the table using the light emitting device 10 as the top plate, light emitted from each of the end faces HE on the four sides of the light transmission layer 4 (indicated by the white arrows) is generated particularly in a dark place. Since a production effect that leaks from the entire surroundings is produced, the atmosphere of the room can be enhanced.

  When the organic EL light-emitting panel 3 of the light-emitting device 10 has a variable emission color and luminance, a controller for controlling the emission color and luminance is provided on the surface of the protective layer 2 or inside the leg portion 20. It is also possible to mount it on the camera so that its emission color and brightness can be changed manually or automatically.

  In the example shown in FIG. 4, the table top is rectangular, but it can be similarly applied to a round or N-square (N is an integer of 3 or more) table top as shown in FIG. It is.

  Moreover, you may make it use the light-emitting device 10 which concerns on this invention as a ceiling lamp in a vehicle interior, as shown in FIG. When the light-emitting device 10 is used as a ceiling lamp in a vehicle interior, light emitted from the end face HE (indicated by a white arrow) becomes indirect light and can illuminate the interior without disturbing the driver's driving. It becomes.

  Moreover, you may make it use the light-emitting device 10 which concerns on this invention as a coaster laid under a cup.

  In the light emitting device 10 according to the above embodiment, the end face HE of the light transmission layer 4 is exposed to the outside as shown in FIG. 2, but the end face HE is transparent or semi-transparent as shown in FIG. You may make it cover with the protection member 9. FIG. At this time, as shown in FIG. 7, the protective member 9 is exposed to the outside. Further, the end face may be covered with a light shielding member so that light does not leak from the end face of the organic light emitting layer 31 of the organic EL light emitting panel 3.

1, 2 Protective layer 3 Organic EL light emitting panel 4 Light transmission layer 5 Light reflection layer

The light emitting device according to claim 1 is a light emitting device including an organic electroluminescence (hereinafter referred to as organic EL) light emitting panel having an organic light emitting layer, and is formed so as to cover a planar light emitting region of the organic EL light emitting panel. and a light transmission layer that is, have a, a light reflecting layer formed on the surface of the light transmitting layer, the end face of the organic light emitting layer is covered by the light blocking member.

Claims (6)

A light emitting device including an organic EL light emitting panel,
A light transmissive layer formed to cover the planar light emitting region of the organic EL light emitting panel;
An opaque light reflection layer formed on the surface of the light transmission layer. The light emitting device according to claim 1, wherein an end surface of the entire circumference of the light transmission layer is exposed to the outside. The light emitting device according to claim 1, wherein an end surface of the entire circumference of the light transmission layer is covered with a transparent or translucent protective member, and the protective member is exposed to the outside. The light-emitting device according to claim 1, wherein the light transmission layer is made of glass or a transparent resin material. 5. The light emitting device according to claim 1, wherein a surface of the light reflecting layer facing the organic EL light emitting panel is a mirror surface. The first protective layer is formed on the light reflection layer, and the second protective layer is formed on the organic EL light emitting panel. The light-emitting device of description.

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