Method to reduce darkening in phosphor in glass (PIG) made by SPS

Patent metadata

Field	Value
Publication number	US-11046607-B2
Application number	US-201916269443-A
Country	US
Kind code	B2
Filing date	Feb 6, 2019
Priority date	Feb 6, 2019
Publication date	Jun 29, 2021
Grant date	Jun 29, 2021

Abstract

A method for preparing a glass composite wavelength converter comprising the steps of providing at least one phosphor material, providing a powder of glass components, mixing the phosphor material and the powder of glass components, thereby preparing a first mixture, adding at least one oxidizing agent to the first mixture, mixing the oxidizing agent with the first mixture, thereby preparing a second mixture, applying pressure and current to the second mixture, thereby preparing a glass composite wavelength converter is described. Furthermore, a glass component wavelength converter and a light source are described.

First claim

What is claimed is:

1. A method for preparing a glass composite wavelength converter, the method comprising:
providing at least one phosphor material;
providing a powder of glass components;
mixing the phosphor material and the powder of glass components, thereby preparing a first mixture;
adding at least one oxidizing agent to the first mixture;
mixing the oxidizing agent with the first mixture, thereby preparing a second mixture; and
applying pressure and current to the second mixture, thereby preparing the glass composite wavelength converter.

2. The method of claim 1 , wherein the phosphor material is YAG:Ce.

3. The method of claim 1 , wherein the glass components have a glass transition temperature of less than about 600° C.

4. The method of claim 1 , wherein the glass components have a glass transition temperature of less than about 400° C.

5. The method of claim 1 , wherein the glass components comprise RO—B 2 O 3 —Al 2 O 3 —SiO 2 , and wherein R is selected from the group consisting of alkali earth metals, Mg, Ca, Sr and Ba.

6. The method of claim 1 , wherein the oxidizing agent is selected from the group consisting of NaNO 3 , LNO 3 , LiNO 3 , Na 2 SO 3 , K 2 SO 3 , LiSO 3 Li 2 SO 3 , and K 2 MnO 4 .

7. The method of claim 1 , wherein the oxidizing agent is added in an amount of less than about 3 wt. % based on an amount of the second mixture.

8. The method of claim 1 , wherein the oxidizing agent is added in an amount of less than about 2 wt. % based on an amount of the second mixture.

9. The method of claim 1 , wherein the oxidizing agent is added in an amount of less than about 1 wt. % based on an amount of the second mixture.

10. The method of claim 1 , wherein the phosphor material is YAG:Ce and the glass components comprise RO—B 2 O 3 —Al 2 O 3 —SiO 2 , and wherein R is selected from the group consisting of alkali earth metals Mg, Ca, Sr and Ba.

11. The method of claim 1 , further comprising applying an inert atmosphere to the second mixture.

12. The method of claim 1 , wherein the pressure is at least about 30 MPa.

13. The method of claim 1 , wherein the glass composite wavelength converter has a quantum efficiency of at least about 80%.

14. The glass composite wavelength converter prepared according to the method of claim 1 .

15. The glass composite wavelength converter of claim 14 , wherein the phosphor material is YAG:Ce.

16. The glass composite wavelength converter of claim 14 , wherein the glass components comprise RO—B 2 O 3 —Al 2 O 3 —SiO 2 , and wherein R is selected from the group consisting of alkali earth metals, Mg, Ca, Sr and Ba.

17. A light source comprising:
a light emitting diode (LED) configured to emit a primary light; and
a glass composite wavelength converter prepared according to the following method:
providing at least one phosphor material;
providing a powder of glass components;
mixing the phosphor material and the powder of glass components, thereby preparing a first mixture;
adding at least one oxidizing agent to the first mixture;
mixing the oxidizing agent with the first mixture, thereby preparing a second mixture; and
applying pressure and current to the second mixture, thereby preparing the glass composite wavelength converter,

wherein the phosphor material is configured to convert at least a portion of the primary light into a secondary light.

18. The light source of claim 17 , wherein the phosphor material is YAG:Ce.

19. The light source of claim 17 , wherein the oxidizing agent is NaNO 3 .

20. The light source of claim 17 , wherein the glass composite wavelength converter has a quantum efficiency of at least about 80%.

Assignees

• Osram Opto Semiconductors Gmbh

Inventors

• Zheng Yi
• Perez Victor E

Classifications

• C09K11/7774

  Aluminates · CPC title

• H10H20/8515

  not being in contact with the bodies · CPC title

• H10H20/8511

  characterised by their material, e.g. binder · CPC title

• H10H20/80

  Constructional details · CPC title

• H10H20/8514 Primary

  characterised by their shape, e.g. plate or foil · CPC title