Light emitting device, display device, and lighting device
A light emitting device includes: a light emitting element; a reflection wall that surrounds the light emitting element; and a diffusion reflection sheet that includes a plurality of particles and permits entrance of emitted light from the light emitting element and reflected light from the reflection wall.
1. A light emitting device, comprising:
a light emitting element comprising an LED (Light Emitting Diode);
a light source substrate having a surface on which the light emitting element is disposed;
a covering material that covers the light emitting element, the covering material having a refractive index between a refractive index of the light emitting element and a refractive index of air;
a reflection wall that surrounds the light emitting element and is in contact with the surface of the light source substrate;
a wavelength conversion sheet that faces the light source substrate;
a diffusion reflection sheet that is in contact with the reflection wall and includes a plurality of particles and permits entrance of emitted light from the light emitting element and reflected light from the reflection wall, wherein the diffusion reflection sheet is formed as a single resin sheet printed with ink including the plurality of particles, and wherein the diffusion reflection sheet is disposed between the wavelength conversion sheet and the light source substrate; and
an optical sheet provided between the diffusion reflection sheet and the wavelength conversion sheet.
2. The light emitting device according to claim 1 , wherein at least some of the plurality of the particles have a hollow structure.
3. The light emitting device according to claim 1 , wherein the plurality of the particles include hollow silica.
4. The light emitting device according to claim 1 , wherein the reflection wall includes a shaped reflection sheet.
5. The light emitting device according to claim 1 , wherein at least a portion of the reflection wall is disposed, between the light source substrate and the diffusion reflection sheet, in a direction crossing the light source substrate.
6. The light emitting device according to claim 5 , wherein the light emitting element is of a side emission type.
7. The light emitting device according to claim 1 , wherein the light emitting element is devoid of a package and a lens.
8. The light emitting device according to claim 1 , wherein the light emitting device includes a plurality of segments partitioned by the reflection wall.
9. The light emitting device according to claim 8 , wherein the plurality of the particles have a predetermined distribution pattern from segment to segment.
10. The light emitting device according to claim 9 , wherein in the distribution pattern, the plurality of the particles is densified directly over the light emitting element.
11. The light emitting device according to claim 8 , wherein a height of the reflection wall varies within a single one of the segments.
12. The light emitting device according to claim 1 , wherein the light emitting element emits light of a blue wavelength range.
13. A display device provided with a display panel and a light emitting device that illuminates the display panel,
the light emitting device comprising:
a light emitting element comprising an LED (Light Emitting Diode);
a light source substrate having a surface on which the light emitting element is disposed;
a covering material that covers the light emitting element, the covering material having a refractive index between a refractive index of the light emitting element and a refractive index of air;
a reflection wall that surrounds the light emitting element and is in contact with the surface of the light source substrate;
a wavelength conversion sheet that faces the light source substrate;
a diffusion reflection sheet that is in contact with the reflection wall and includes a plurality of particles and permits entrance of emitted light from the light emitting element and reflected light from the reflection wall, wherein the diffusion reflection sheet is formed as a single resin sheet printed with ink including the plurality of particles, and wherein the diffusion reflection sheet is disposed between the wavelength conversion sheet and the light source substrate; and
an optical sheet provided between the diffusion reflection sheet and the wavelength conversion sheet.
14. The display device according to claim 13 , wherein the light emitting device includes a plurality of segments partitioned by the reflection wall, and wherein the plurality of the particles have a distribution pattern from segment to segment.
15. A lighting device provided with a light emitting device,
the light emitting device comprising:
a light emitting element comprising an LED (Light Emitting Diode);
a light source substrate having a surface on which the light emitting element is disposed;
a covering material that covers the light emitting element, the covering material having a refractive index between a refractive index of the light emitting element and a refractive index of air;
a reflection wall that surrounds the light emitting element and is in contact with the surface of the light source substrate;
a wavelength conversion sheet that faces the light source substrate;
a diffusion reflection sheet that is in contact with the reflection wall and includes a plurality of particles and permits entrance of emitted light from the light emitting element and reflected light from the reflection wall, wherein the diffusion reflection sheet is formed as a single resin sheet printed with ink including the plurality of particles, and wherein the diffusion reflection sheet is disposed between the wavelength conversion sheet and the light source substrate; and
an optical sheet provided between the diffusion reflection sheet and the wavelength conversion sheet.
16. The lighting device according to claim 15 , wherein the plurality of the particles have a distribution pattern in which the plurality of the particles is densified directly over the light emitting element.