Illumination device comprising first, second, and third reflectors, a lightguide, and a light-emitting layer and display device
According to one embodiment, an illumination device includes a lightguide, a light-emitting layer, a first reflector, a second reflector, and a third reflector. A distance between the first reflector and the second reflector is greater at a second position farther from the light-emitting layer than at a first position closer to the light-emitting layer. A distance between the lightguide and the third reflector is greater at a fourth position farther from the first reflector than at a third position closer to the first reflector. An emission portion for allowing emission of light emitted from the light-emitting layer is formed between the second reflector and the third reflector.
1. An illumination device comprising:
a light source;
a lightguide which includes an upper surface, and guides the light from the light source;
a light-emitting layer which is disposed on the upper surface, and emits light based on the light from the light source;
a first reflector disposed on the upper surface;
a second reflector located above the first reflector and the light-emitting layer at an interval; and
a third reflector which is located above the upper surface, and is more separated from the light-emitting layer than the first reflector,
a distance between the first reflector and the second reflector being greater at a second position farther from the light-emitting layer than at a first position closer to the light-emitting layer,
a distance between the lightguide and the third reflector being greater at a fourth position farther from the first reflector than at a third position closer to the first reflector,
an emission portion for allowing emission of light emitted from the light-emitting layer being formed between the second reflector and the third reflector.
2. The illumination device of claim 1 , wherein:
the first reflector includes a first end portion located on a side separated from the light-emitting layer; and
the second reflector includes a second end portion located to be directly above the first end portion, or closer to the third reflector than a position directly above the first end portion.
3. The illumination device of claim 1 , further comprising an optical propagation layer surrounded by the first to third reflectors, wherein
a maximum distance between the lightguide and the optical propagation layer is less than or equal to a maximum distance between the lightguide and the third reflector.
4. The illumination device of claim 1 , wherein in a region in which the light-emitting layer and the second reflector face each other, a position at which a distance between the lightguide and the second reflector becomes the smallest exists.
5. The illumination device of claim 1 , wherein:
the second and the third reflectors are inclined with respect to the upper surface; and
a first inclination angle between the second reflector and the upper surface is smaller than a second inclination angle between the third reflector and the upper surface.
6. The illumination device of claim 5 , wherein the first inclination angle is greater at the second position than at the first position.
7. The illumination device of claim 5 , wherein the first inclination angle is smaller at the second position than at the first position.
8. The illumination device of claim 1 , further comprising a diffusion layer over the emission portion.
9. The illumination device of claim 1 , further comprising a fourth reflector disposed on the upper surface of the lightguide, and a projection located on the fourth reflector.
10. The illumination device of claim 1 , further comprising a vertical alignment film located between the lightguide and the light-emitting layer, wherein
the light-emitting layer includes phosphors arranged in a normal direction of the lightguide.
11. The illumination device of claim 1 , further comprising an optical absorption layer located on the second reflector.
12. A display device comprising:
an insulating film;
a light-emitting element disposed on the insulating film;
a first reflector disposed on the insulating film;
a second reflector located above the first reflector and the light-emitting element at an interval; and
a third reflector which is located above the insulating film, and is more separated from the light-emitting element than the first reflector,
a distance between the first reflector and the second reflector being greater at a second position farther from the light-emitting element than at a first position closer to the light-emitting element,
a distance between the insulating film and the third reflector being greater at a fourth position farther from the first reflector than at a third position closer to the first reflector,
an emission portion for allowing emission of light emitted from the light-emitting element being formed between the second reflector and the third reflector.
13. The display device of claim 12 , further comprising a switching element, wherein
the light-emitting element comprises:
a first electrode disposed on the insulating film, and electrically connected to the switching element;
a light-emitting layer disposed on the first electrode; and
a second electrode disposed on the light-emitting layer.
14. The display device of claim 13 , further comprising an interlayer insulating film located between the first and third reflectors and the second electrode, wherein:
the first reflector is located in a same layer as the first electrode, and is separated from the first electrode; and
the interlayer insulating film is located between the first reflector and the first electrode.
15. The display device of claim 12 , further comprising a first insulating substrate, a second insulating substrate, a first projection which protrudes from the first insulating substrate toward the second insulating substrate, and a second projection which protrudes from the second insulating substrate toward the first insulating substrate, wherein
the light-emitting element is located directly under the second projection; and
the emission portion is located between the first projection and the second projection, and is located closer to the first projection than to the second projection.
16. A display device comprising:
a light source;
a first substrate comprising a lightguide which includes an upper surface, and guides light from the light source, a light-emitting layer which is disposed on the upper surface, and emits light based on the light from the light source, a first reflector disposed on the upper surface, a second reflector located above the first reflector and the light-emitting layer at an interval, and a third reflector which is located above the upper surface, and is more separated from the light-emitting layer than the first reflector;
a liquid crystal layer disposed on the first substrate; and
a second substrate disposed on the liquid crystal layer, wherein
a distance between the first reflector and the second reflector being greater at a second position farther from the light-emitting layer than at a first position closer to the light-emitting layer,
a distance between the lightguide and the third reflector being greater at a fourth position farther from the first reflector than at a third position closer to the first reflector,
an emission portion for allowing emission of light emitted from the light-emitting layer being formed between the second reflector and the third reflector.
17. The display device of claim 16 , wherein the second substrate further comprises a switching element and a pixel electrode electrically connected to the switching element.
18. The display device of claim 16 , wherein:
the first substrate further comprises an optical absorption layer between the lightguide and the light-emitting layer; and
the optical absorption layer transmits light from the light source, and absorbs light emitted from the light-emitting layer.
19. The display device of claim 16 , wherein:
the first substrate further comprises a first projection and a second projection disposed between the lightguide and the liquid crystal layer;
the emission portion and the light-emitting layer are located between the first projection and the second projection;
the emission portion is located closer to the second projection than to the first projection; and
the light-emitting layer is located closer to the first projection than to the second projection.
20. The display device of claim 19 , further comprising an optical propagation layer surrounded by the first to third reflectors; and
a film thickness of the optical propagation layer is smaller on a first side close to the first projection than on a second side close to the second projection.