JP2016081820A - Light-emitting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To cause light from a light source to be efficiently radiated from an edge part of a mirror.SOLUTION: A light emitting device 10 has a planar light source 100, a mirror 200 and a light guide member 300. The mirror 200 overlaps at least a part of the planar light source 100. The light guide member 300 is positioned between the planar light source 100 and the mirror 200. Then, the light guide member 300, as shown in Fig.3, has the first surface 302 and the second surface 304. The first surface 302 is oppositely faced against the planar light source 100 to receive light from the planar light source 100 into the light guide member 300. The second surface 304 is an opposite surface of the first surface 302 and radiates light received from the planar light source 100 from a region not covering the mirror 200.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a light emitting device.

  In recent years, organic EL elements have been used as light sources for lighting devices. When the organic EL element is used, the light source of the lighting device can be a surface light source.

  On the other hand, Patent Document 1 describes that light for illumination is emitted from the edge of a mirror. Specifically, it is described that a light source is disposed below the light diffusion plate, and a mirror that is slightly smaller than the diffusion plate is disposed on one surface of the diffusion plate. If it does in this way, light will inject from the lower end of a diffuser, and this light will be diffused within a diffuser, and light will be emitted from a field which is not covered with a mirror among diffusers.

  In Patent Document 2, a plurality of organic EL elements are partitioned and formed on a transparent substrate, and the organic EL element located on the edge of the transparent substrate is caused to emit light, whereby a portion of the organic EL element that does not emit light is mirrored. And using the light emitting portion of the organic EL element as a light source is described.

JP-A-7-155242 Japanese Patent Application Laid-Open No. 2005-177084

  As described in Patent Document 1, it is desired to emit illumination light from the edge of a mirror. The present inventor has studied to efficiently emit light from the light source from the edge of the mirror.

  An example of a problem to be solved by the present invention is to efficiently emit light from a light source from the edge of a mirror.

The invention according to claim 1 is a surface light source;
A mirror overlapping at least part of the surface light source;
A light guide member positioned between the surface light source and the mirror;
With
The light guide member is
A first surface facing the surface light source and receiving light from the surface light source into the light guide member;
A second surface that radiates light from the surface light source from a region that is opposite to the first surface and opposed to the mirror and that does not overlap the mirror;
It is a light-emitting device provided with.

It is a top view which shows the structure of the light-emitting device which concerns on embodiment. It is AA sectional drawing of FIG. It is the figure which expanded the area | region enclosed with the dotted line (alpha) of FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, the same reference numerals are given to the same components, and the description will be omitted as appropriate.

  FIG. 1 is a plan view showing a configuration of a light emitting device 10 according to the embodiment. 2 is a cross-sectional view taken along the line AA in FIG. FIG. 3 is an enlarged view of a region surrounded by a dotted line α in FIG. The light emitting device 10 according to the embodiment includes a surface light source 100, a mirror 200, and a light guide member 300. The mirror 200 overlaps at least a part of the surface light source 100. The light guide member 300 is located between the surface light source 100 and the mirror 200. And the light guide member 300 has the 1st surface 302 and the 2nd surface 304, as shown in FIG. The first surface 302 faces the surface light source 100 and receives light from the surface light source 100 into the light guide member 300. The second surface 304 is a surface opposite to the first surface 302, and emits light received from the surface light source 100 from a region not overlapping the mirror 200. Details will be described below.

  The surface light source 100 includes a substrate 110 and a light emitting unit 120. The light emitting unit 120 is formed on one surface of the substrate 110.

The substrate 110 is a light-transmitting substrate such as a glass substrate or a resin substrate. The substrate 110 may have flexibility. In the case of flexibility, the thickness of the substrate 110 is, for example, not less than 10 μm and not more than 1000 μm. The substrate 110 is, for example, a polygon such as a rectangle or a circle. When the substrate 110 is a resin substrate, the substrate 110 is formed using, for example, PEN (polyethylene naphthalate), PES (polyethersulfone), PET (polyethylene terephthalate), or polyimide. In the case where the substrate 110 is a resin substrate, an inorganic barrier film such as SiN _x or SiON is formed on at least one surface (preferably both surfaces) of the substrate 110 in order to prevent moisture from passing through the substrate 110. It is preferable.

  The light emitting unit 120 includes an organic EL element as a light emitting element. This organic EL element has a configuration in which a first electrode, an organic layer, and a second electrode are laminated in this order.

  The first electrode is a transparent electrode having optical transparency. The material of the transparent electrode is a material containing a metal, for example, a metal oxide such as ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), IWZO (Indium Tungsten Zinc Oxide), or ZnO (Zinc Oxide). The thickness of the first electrode is, for example, not less than 10 nm and not more than 500 nm. The first electrode is formed using, for example, a sputtering method or a vapor deposition method. The first electrode may be a carbon nanotube or a conductive organic material such as PEDOT / PSS.

  The organic layer has, for example, a configuration in which a hole injection layer, a light emitting layer, and an electron injection layer are stacked in this order. A hole transport layer may be formed between the hole injection layer and the light emitting layer. In addition, an electron transport layer may be formed between the light emitting layer and the electron injection layer. The organic layer may be formed by a vapor deposition method. In addition, at least one of the organic layers, for example, a layer in contact with the first electrode may be formed by a coating method such as an inkjet method, a printing method, or a spray method. In this case, the remaining layers of the organic layer are formed by vapor deposition. Further, all layers of the organic layer may be formed using a coating method.

  The second electrode is made of, for example, a metal selected from the first group consisting of Al, Au, Ag, Pt, Mg, Sn, Zn, and In, or an alloy of a metal selected from the first group. Contains a metal layer. In this case, the second electrode has a light shielding property. The thickness of the second electrode is, for example, not less than 10 nm and not more than 500 nm. However, the second electrode may be formed using the material exemplified as the material of the first electrode. The second electrode is formed using, for example, a sputtering method or a vapor deposition method.

  In the example shown in the figure, the light emitting unit 120 is formed on almost the entire surface of the substrate 110 excluding the edge, for example. In plan view, the entire light emitting unit 120 overlaps the mirror 200. However, a part of the light emitting unit 120 may protrude from the mirror 200. The light emission surface of the surface light source 100 is a surface of the substrate 110 opposite to the light emitting unit 120. For this reason, the surface of the surface light source 100 opposite to the light emitting unit 120 in the substrate 110 faces the mirror 200.

  As shown in FIG. 3, the light guide member 300 has a first surface 302 and a second surface 304. The first surface 302 faces the surface light source 100, and light from the surface light source 100 enters the light guide member 300. The first surface 302 may be incident on the light guide member 300 at least in a region facing the surface light source 100. For this reason, in the area | region (for example, edge of the light guide member 300) which does not overlap with the surface light source 100, the light does not need to enter into the inside from the 1st surface 302. FIG.

  In the example shown in the drawing, the light guide member 300 includes a light guide part 310 serving as a light guide unit and a diffusion part 320 serving as a diffusion unit. The light guide unit 310 is located in a region of the light guide member 300 that overlaps with the mirror 200, and the diffusion unit 320 is located in a region of the light guide member 300 that does not overlap with the mirror 200. The light guide member 300 guides the light received from the first surface 302 toward the diffusion unit 320. The diffusion unit 320 diffuses the light guided by the light guide member 300. Thereby, the light emitted from the surface light source 100 is emitted from the portion of the light guide member 300 located around the mirror 200. In the example shown in the figure, the light guide unit 310 and the diffusion unit 320 are integrally formed. For example, the light guide unit 310 and the diffusion unit 320 are formed by processing at least one of the region serving as the light guide unit 310 and the region serving as the diffusion unit 320 with respect to the light guide member 300. Moreover, you may form the one light guide member 300 by joining after forming the light guide part 310 and the spreading | diffusion part 320 by a separate member.

  As described above, according to the present embodiment, the light emitted from the surface light source 100 is incident on the first surface 302 of the light guide unit 310, then guided to the diffusion unit 320, and from the second surface 304 of the diffusion unit 320. Radiated to the outside. The second surface 304 of the diffusing unit 320 does not overlap the mirror 200. Therefore, the light emitted from the surface light source 100 is efficiently emitted from the periphery of the mirror 200.

  Further, since the diffusion unit 320 diffuses light, the light emitted from the diffusion unit 320 becomes soft light.

  As mentioned above, although embodiment was described with reference to drawings, these are illustrations of this invention and various structures other than the above are also employable.

DESCRIPTION OF SYMBOLS 10 Light-emitting device 100 Surface light source 200 Mirror 300 Light guide member 302 1st surface 304 2nd surface 310 Light guide part 320 Diffusion part

Claims (3)

A surface light source;
A mirror overlapping at least part of the surface light source;
A light guide member positioned between the surface light source and the mirror;
With
The light guide member is
A first surface facing the surface light source and receiving light from the surface light source into the light guide member;
A second surface that radiates light from the surface light source from a region that is opposite to the first surface and opposed to the mirror and that does not overlap the mirror;
A light emitting device comprising: The light-emitting device according to claim 1.
The region of the light guide member that overlaps the mirror has light guide means for guiding light received from the first surface,
A region of the light guide member that does not overlap the mirror has a diffusing unit that diffuses light guided by the light guide member. The light-emitting device according to claim 2.
A light emitting device in which the light guiding means and the diffusing means are integrally formed.

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