Light emitting device

Patent metadata

Field	Value
Publication number	US-11038089-B2
Application number	US-202016898388-A
Country	US
Kind code	B2
Filing date	Jun 10, 2020
Priority date	Apr 6, 2016
Publication date	Jun 15, 2021
Grant date	Jun 15, 2021

Abstract

A light emitting device is provided. The light emitting device includes a light emitting element, which emits blue light, and a light transmissive member having a first principal face bonded to the light emitting element and a second principal face opposite the first principal face. The light transmissive member has a light transmissive base material and wavelength conversion substances, which are contained in the base material and which absorb the light from the light emitting element and emit light. The wavelength conversion substances are localized in the base material towards the first principal face, and include a first phosphor which emits green to yellow light and a second phosphor which emits red light. The first phosphor is more localized towards the first principal face than the second phosphor. The second phosphor is a manganese-activated fluoride phosphor.

First claim

What is claimed is:

1. A method of producing a light emitting device comprising the steps of:
preparing a wavelength conversion sheet having a first principal face and a second. principal face main opposite to the first phosphor, the wavelength conversion sheet including a phosphor that are more localized towards the first principal face than the second principal face;
preparing a light transmissive member by cutting the wavelength conversion sheet into small pieces using an ultrasonic cutter;
applying a light guide member on a light emitting device and placing the light transmissive member on the light emitting device via the light guide member;
forming a cover member that embed the light emitting device, the light guide member and the light transmissive member; and
exposing an upper face of the light transmissive member by grinding the cover member using a grinder.

2. The method of producing the light emitting device according to claim 1 , further comprising the step of flip-chip mounting the light emitting device on an aggregate substrate before the applying and placing step.

3. The method of producing the light emitting device according to claim 2 , wherein the flip-chip mounting step includes the step of applying a conductive bonding member on element connection terminals of the aggregate substrate.

4. The method of producing the light emitting device according to claim 1 , wherein the phosphor includes an europium-activated β-sialon phosphor.

5. The method of producing the light emitting device according to claim 1 , wherein the phosphor includes a manganese-activated fluoride phosphor.

Assignees

• Nichia Corp

Inventors

• Ikeda Tadaaki
• Nakabayashi Takuya

Classifications

• C09K11/77348

  Silicon Aluminium Nitrides or Silicon Aluminium Oxynitrides · CPC title

• H10H20/882

  Scattering means (H10H20/82 takes precedence) · CPC title

• H10H20/841

  Reflective coatings, e.g. dielectric Bragg reflectors · CPC title

• H10H20/856

  Reflecting means · CPC title

• H10H20/854

  characterised by their material, e.g. epoxy or silicone resins · CPC title