Red phosphor, white light source, light emitting device, and method for forming the red phosphor

Patent metadata

Field	Value
Publication number	US-9862884-B2
Application number	US-201414899520-A
Country	US
Kind code	B2
Filing date	May 19, 2014
Priority date	Jun 17, 2013
Publication date	Jan 9, 2018
Grant date	Jan 9, 2018

Abstract

The present invention relates to a red phosphor, which includes an element A, magnesium, aluminum, oxygen, and manganese in Chemical Formula (1) that is (A 1−x Mg x ) 4 AI 14−y O 25 :γMn 4+ . The element A in the Chemical Formula (1) is at least one of strontium, barium, and calcium, and x and y in the Chemical Formula (1) satisfy the relational expressions 0<=x<1 and 0<y<1.

First claim

The invention claimed is:

1. A red phosphor comprising:
an element A, magnesium, aluminum, oxygen, and manganese in Chemical Formula (1),
(A 1−x Mg x ) 4 Al 14−y O 25 :yMn 4+ ,

wherein the element A in the Chemical Formula (1) comprises an element selected from the group consisting of barium, calcium, combinations of barium and calcium and a combination of strontium, barium and calcium, and
wherein 0<x<1 and 0<y<1.

2. The red phosphor according to claim 1 , wherein the red phosphor has an emission peak with wavelength between 635 nm and 675 nm.

3. The red phosphor according to claim 2 , wherein the red phosphor has an emission peak at 652 nm.

4. A light emitting device comprising:
a light source configured to emit light; and
a red phosphor, which is configured to be excited by at least partial light to generate excited light with a higher wavelength than that of the light emitted by the light source, the red phosphor comprising:
an element A, magnesium, aluminum, oxygen, and manganese in Chemical Formula (1),
(A 1−x Mg x ) 4 Al 14−y O 25 :yMn 4+ ,

wherein the element A in the Chemical Formula (1) comprises an element selected from the group consisting of barium, calcium, combinations of barium and calcium and a combination of strontium, barium and calcium, and
wherein 0<x<1 and 0<y<1.

5. The light emitting device according to claim 4 , wherein the light source provides light with a wavelength between 450 nm and 470 nm.

6. The light emitting device according to claim 4 , wherein the light source provides light with a wavelength between 275 nm and 375 nm.

7. The light emitting device according to claim 4 , wherein the light source is configured as an LED.

8. The light emitting device according to claim 4 , wherein the red phosphor has an emission peak with a wavelength between 635 nm and 675 nm.

9. The light emitting device according to claim 8 , wherein the red phosphor has an emission peak at 652 nm.

10. A method for forming a red phosphor having Chemical Formula (1)
(A 1−x Mg x ) 4 Al 14−y O 25 :yMn 4+ ,
wherein element A in the Chemical Formula (1) comprises an element selected from the group consisting of strontium, barium, calcium, and combinations thereof, and wherein 0≦x<1and 0<y<1, the method comprising:
selecting a compound containing the element A, Al 2 O 3 , MnO 2 , and 4MgCO 3 •Mg(OH) 2 •4H 2 O as raw materials;
weighing the raw materials in a molar ratio according to the Chemical Formula (1);
adding a flux to the raw materials to form a mixture; and
calcining the mixture at a temperature of 1300° C.-1600° C. for 2 to 6 hours to form a calcinated product,
wherein the method further comprises washing the calcinated product using water or hot water or wherein the flux includes at least one of magnesium fluoride and calcium fluoride or wherein calcining the mixture comprises increasing the temperature from 1300° C. to 1600° C. at a rate of 5° C./min-10° C./min.

11. The method according to Claim 10 , further comprising:
grinding the mixture before the calcining; and
grinding the calcinated product.

Assignees

• Osram Gmbh

Inventors

• Liu zhong shi
• Zhao Wenhui
• Jing Xiping

Classifications

• Y02B20/181

  Cross-Sectional Technologies · mapped topic

• C09K11/643 Primary

  with alkaline earth metals · CPC title

• H01L33/502

  Electricity · mapped topic

• Y02B20/00

  Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps · CPC title

• H10H20/8512

  Wavelength conversion materials · CPC title