Light-emitting module and planar light source

Patent metadata

Field	Value
Publication number	US-11674666-B2
Application number	US-202217837746-A
Country	US
Kind code	B2
Filing date	Jun 10, 2022
Priority date	Jul 21, 2020
Publication date	Jun 13, 2023
Grant date	Jun 13, 2023

Abstract

A light-emitting module includes: a light source; a light guide plate including an upper surface and a lower surface, the lower surface being at a side opposite to the upper surface, the light guide plate being configured to guide light from the light source; a wavelength conversion sheet located at an upper surface side of the light guide plate; a first light-reflective member located at a lower surface side of the light guide plate, the first light-reflective member including: a first resin member, and a first reflector, where a refractive index of the first reflector is lower than a refractive index of the first resin member; and a second light-reflective member located at a lower surface side of the first light-reflective member, wherein the second light-reflective member includes: a second resin member, and a second reflector, where a refractive index of the second reflector is higher than a refractive index of the second resin member.

First claim

What is claimed is:

1. A light-emitting module comprising:
a light source;
a light guide plate including an upper surface and a lower surface, the lower surface being at a side opposite to the upper surface, the light guide plate being configured to guide light from the light source;
a wavelength conversion sheet located at an upper surface side of the light guide plate;
a first light-reflective member located at a lower surface side of the light guide plate, wherein the first light-reflective member comprises:
a first resin member, and
a first reflector,
wherein a refractive index of the first reflector is lower than a refractive index of the first resin member; and

a second light-reflective member located at a lower surface side of the first light-reflective member, wherein the second light-reflective member comprises:
a second resin member, and
a second reflector,
wherein a refractive index of the second reflector is higher than a refractive index of the second resin member.

2. The module according to claim 1 , wherein:
the wavelength conversion sheet includes a red phosphor and a green phosphor.

3. The module according to claim 1 , wherein:
the wavelength conversion sheet includes a first wavelength conversion sheet including a red phosphor, and a second wavelength conversion sheet including a green phosphor.

4. The module according to claim 2 , wherein:
the red phosphor is a fluoride-based phosphor or a quantum dot phosphor.

5. The module according to claim 3 , wherein:
the red phosphor is a fluoride-based phosphor or a quantum dot phosphor.

6. The module according to claim 2 , wherein:
the green phosphor is a phosphor having a perovskite structure or a quantum dot phosphor.

7. The module according to claim 3 , wherein:
the green phosphor is a phosphor having a perovskite structure or a quantum dot phosphor.

8. The module according to claim 1 , wherein:
the first reflector is a bubble.

9. The module according to claim 1 , wherein:
the second reflector is a titanium oxide particle.

10. The module according to claim 1 , wherein:
the refractive index of the second resin is lower than the refractive index of the first resin member.

11. The module according to claim 1 , wherein:
the first resin member is formed of a polyethylene terephthalate resin, an olefin resin, an acrylic resin, a silicone resin, a urethane resin, or an epoxy resin.

12. The module according to claim 1 , wherein:
the second resin member is formed of an acrylic resin, a silicone resin, a urethane resin, or an epoxy resin.

13. The module according to claim 1 , wherein:
a thickness of the second light-reflective member is less than a thickness of the first light-reflective member.

14. The module according to claim 1 , wherein:
the first light-reflective member faces the lower surface of the light guide plate and a lower surface of the light source.

15. The module according to claim 14 , wherein:
the second light-reflective member faces an entire lower surface of the first light-reflective member.

16. The module according to claim 1 , wherein:
the light guide plate includes a hole portion, and
the light source is located in the hole portion.

17. The module according to claim 16 , wherein:
the hole portion is a bottomed hole portion that is open at the lower surface side of the light guide plate.

18. The module according to claim 16 , wherein:
the hole portion is a through-hole extending from the upper surface to the lower surface of the light guide plate.

19. A planar light source, comprising:
the light-emitting module according to claim 1 ; and
a wiring substrate;
wherein the first light-reflective member and the second light-reflective member are located between the wiring substrate and the lower surface of the light guide plate.

Assignees

• Nichia Corp

Inventors

• Iwakura Daisuke

Classifications

• G02B6/0055

  Reflecting element, sheet or layer · CPC title

• F21V7/0066

  specially adapted to cooperate with point like light sources; specially adapted to cooperate with light sources the shape of which is unspecified (F21V7/16 - F21V7/30 take precedence) · CPC title

• F21V5/043 Primary

  the lens having cylindrical faces, e.g. rod lenses, toric lenses · CPC title

• G02B6/0021

  for housing at least a part of the light source, e.g. by forming holes or recesses · CPC title

• G02B6/0031

  Reflecting element, sheet or layer · CPC title