Light-emitting unit and surface-emission light source

Patent metadata

Field	Value
Publication number	US-11901498-B2
Application number	US-202318102240-A
Country	US
Kind code	B2
Filing date	Jan 27, 2023
Priority date	Aug 2, 2019
Publication date	Feb 13, 2024
Grant date	Feb 13, 2024

Abstract

A light-emitting unit includes: a wiring board; light-emitting elements on the wiring board; a light reflecting member on the wiring board, the light reflecting member covering a lateral surface of each of the light-emitting elements; wavelength conversion layers each provided on or above an emission surface of a corresponding one of the plurality of light-emitting elements; light reflecting layers on the wavelength conversion layers, respectively; and a protecting layer configured to transmit light and provided on the light reflecting member. The light-transmitting protecting layer covers at least a lateral surface of the wavelength conversion layers and at least a lateral surfaces of the light reflecting layers. An upper surface of the protecting layer has a first recess in a region where the plurality of light reflecting layers are not present in a top view. The first recess includes at least one concave surface.

First claim

The invention claimed is:

1. A light-emitting unit comprising:
a wiring board having a wire layer;
a plurality of light-emitting elements provided in an array on the wiring board and electrically connected with the wire layer of the wiring board;
a sheet-like light reflecting member provided on the wiring board, the light reflecting member having a plurality of throughholes;
a plurality of wavelength conversion layers each covering an upper surface of a corresponding one of the plurality of light-emitting elements;
a plurality of light reflecting layers each being provided on a corresponding one of the plurality of wavelength conversion layers and being capable of transmitting a part of incoming light and reflecting another part of the incoming light; and
a protecting layer provided on at least a part of the light reflecting member, wherein
each of the plurality of light-emitting elements is located inside a corresponding one of the plurality of throughholes in a top view, and
the protecting layer has one or more grooves each located between two adjoining light-emitting elements in the array of the plurality of light-emitting elements, each groove penetrating through the protecting layer.

2. The light-emitting unit of claim 1 , wherein the one or more grooves define a matrix of compartments in a top view, such that a corresponding one of the plurality of light-emitting elements is surrounded within each compartment.

3. The light-emitting unit of claim 1 , further comprising a light reflective partitioning member, the partitioning member comprising a portion located in each of the one or more grooves.

4. The light-emitting unit of claim 2 , further comprising a light reflective partitioning member, the partitioning member comprising a portion located in each of the one or more grooves.

5. The light-emitting unit of claim 3 , wherein the partitioning member is a layer covering at least a part of an inner lateral surface that defines each of the one or more grooves.

6. The light-emitting unit of claim 4 , wherein the partitioning member is a layer covering at least a part of an inner lateral surface that defines each of the one or more grooves.

7. The light-emitting unit of claim 3 , wherein the partitioning member is a resin layer.

8. The light-emitting unit of claim 4 , wherein the partitioning member is a resin layer.

9. The light-emitting unit of claim 5 , wherein the partitioning member is a resin layer.

10. The light-emitting unit of claim 6 , wherein the partitioning member is a resin layer.

11. The light-emitting unit of claim 1 , wherein each of the one or more grooves has an opening at an upper surface of the protecting layer, with a cross-sectional shape such that the groove has a greater width inside the protecting layer than at the opening of the groove.

12. The light-emitting unit of claim 2 , wherein each of the one or more grooves has an opening at an upper surface of the protecting layer, with a cross-sectional shape such that the groove has a greater width inside the protecting layer than at the opening of the groove.

13. The light-emitting unit of claim 1 , wherein the plurality of wavelength conversion layers respectively overlap the plurality of light reflecting layers in a top view, and at least a portion of each wavelength conversion layer or at least a portion of each light reflecting layer contains the upper surface of the corresponding one of the plurality of light-emitting elements in a top view.

14. The light-emitting unit of claim 2 , wherein the plurality of wavelength conversion layers respectively overlap the plurality of light reflecting layers in a top view, and at least a portion of each wavelength conversion layer or at least a portion of each light reflecting layer contains the upper surface of the corresponding one of the plurality of light-emitting elements in a top view.

15. The light-emitting unit of claim 1 , wherein each of the plurality of light reflecting layers has a dotted reflection pattern in a top view, and,
in each of the plurality of light reflecting layers, the reflection pattern increases in dot density from a periphery to a center of the light reflecting layer.

16. The light-emitting unit of claim 1 , wherein the wiring board is a flexible printed circuit.

17. The light-emitting unit of claim 1 , wherein the light reflecting member is a resin sheet.

18. The light-emitting unit of claim 1 , further comprising a circuit element provided on the wiring board, and the light reflecting member covers the circuit element.

19. The light-emitting unit of claim 18 , wherein the circuit element is a driver connected with two or more of the plurality of light-emitting elements or a protection element.

20. A surface-emission light source comprising:
the light-emitting unit according to claim 1 ;
a diffuser provided on or above the light-emitting unit; and
a prism sheet provided on or above the diffuser.

Assignees

• Nichia Corp

Inventors

• Nakabayashi Takuya
• Katsumata Toshinobu
• Hiraide Noriaki

Classifications

• H10W90/00 Primary

  Package configurations · CPC title

• H10H20/872

  Periodic patterns for optical field-shaping, e.g. photonic bandgap structures · CPC title

• H10H29/142

  Two-dimensional arrangements, e.g. asymmetric LED layout · CPC title

• H10H20/8506

  Containers · CPC title

• H10H20/856

  Reflecting means · CPC title