Planar light source and method of manufacturing planar light source

Patent metadata

Field	Value
Publication number	US-11808969-B2
Application number	US-202217943519-A
Country	US
Kind code	B2
Filing date	Sep 13, 2022
Priority date	Jun 4, 2020
Publication date	Nov 7, 2023
Grant date	Nov 7, 2023

Abstract

A method of manufacturing a planar light source includes: providing a wiring substrate; locating a light guide plate on a first principal face of the wiring substrate, wherein the light guide plate includes a plurality of unit regions arranged in one dimension or two dimensions, and a plurality of through holes that are open at the a principal face and a second principal face of the light guide plate, wherein at least one of the through holes is located in the unit regions; locating light sources in the through holes in the unit regions on the first principal face of the wiring substrate; locating a first light transmissive member in a first of the through holes; and locating a second light transmissive member in the first through hole.

First claim

What is claimed is:

1. A method of manufacturing a planar light source, the method comprising:
providing a wiring substrate comprising:
a first principal face, and
a second principal face located opposite the first principal face;

locating a light guide plate on the first principal face of the wiring substrate, wherein the light guide plate comprises:
a first principal face,
a second principal face located opposite the first principal face,
a plurality of unit regions arranged in one dimension or two dimensions, and
a plurality of through holes that are open at the first principal face and the second principal face, wherein at least one of the through holes is located in the unit regions;

locating light sources in the through holes in the unit regions on the first principal face of the wiring substrate;
locating a first light transmissive member in a first of the through holes so as to cover at least a portion of a lateral face of at least one light source located in the first through hole;
after the step of locating the first light transmissive member:
electrically connecting the light sources and the wiring substrate, and
inspecting light emitted from the light sources by lighting the light sources; and

after the steps of electrically connecting the light sources and the wiring substrate and inspecting the light emitted from the light sources, locating a second light transmissive member in the first through hole so as to cover at least an upper face of the first light transmissive member; wherein:
in the step of locating the second light transmissive member, a phosphor is added to the second light transmissive member based on a result of the step of inspecting the light emitted from the light sources.

2. The method of manufacturing a planar light source according to claim 1 , further comprising:
forming a plurality of sectioning grooves that are open at the first principal face of the light guide plate and that, in a top view, surround the unit regions along perimeters of the unit regions, and
locating a plurality of light reflecting members in the sectioning grooves.

3. The method of manufacturing a planar light source according to claim 1 , further comprising:
subsequent to the step of locating the second light transmissive member, locating at least one light shielding member on an upper face of the second light transmissive member.

4. The method of manufacturing a planar light source according to claim 1 , wherein:
the upper face of the first light transmissive member comprises a recessed part recessed towards the second principal face of the light guide plate, and
a lower face of the second light transmissive member comprises a first protrusion part that is in contact with the upper face of the first light transmissive member and protrudes towards the second principal face side of the light guide plate.

5. The method of manufacturing a planar light source according to claim 1 , wherein:
the first light transmissive member entirely covers lateral faces of the at least one light source located in the first through hole.

6. The method of manufacturing a planar light source according to claim 1 , wherein:
the phosphor is localized on a lower face side of the second light transmissive member.

7. The method of manufacturing a planar light source according to claim 1 , wherein:
the second light transmissive member further covers an upper face of the at least one light source located in the first through hole.

Assignees

• Nichia Corp

Inventors

• Kasai Daisuke

Classifications

• G02B6/0083 Primary

  Details of electrical connections of light sources to drivers, circuit boards, or the like · CPC title

• F21V23/002

  Arrangements of cables or conductors inside a lighting device, e.g. means for guiding along parts of the housing or in a pivoting arm · CPC title

• F21V33/0052

  Audio or video equipment, e.g. televisions, telephones, cameras or computers; Remote control devices therefor · CPC title

• F21Y2105/16

  square or rectangular, e.g. for light panels · CPC title

• G02F1/133524

  Light-guides, e.g. fibre-optic bundles, louvered or jalousie light-guides · CPC title