Red phosphor and white light illumination device utilizing the same

• US 20080136310A1
• Filed: 07/05/2007
• Published: 06/12/2008
• Est. Priority Date: 12/07/2006
• Status: Active Grant

• Current Assignee: Industrial Technology Research Institute
• Original Assignee: Industrial Technology Research Institute
• Inventors: Yeh, Yao-Tsung, Chiu, Yi-Chen, Chen, Teng-Ming, Jang, Shyue-Ming, Wang, Shian-Jy
• Granted Patent: US 7,633,219 B2
• Time in Patent Office: Days
• US Class Current: 313/485
• CPC Class Codes: C09K 11/77922 Silicates
• CPC Class Codes: H01L 33/504 Elements with two or more wavelength conversion materials
• CPC Class Codes: H05B 33/14 characterised by the chemical or physical composition or the arrangement of the electroluminescent material , or by the simultaneous addition of the electroluminescent material in or onto the light source
• CPC Class Codes: Y02B 20/00 Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps

Abstract

The invention provides a red phosphor composed of M(Eu_1-x-yLa_xBi_y)₄Si₃O₁₃, wherein M is Ca, Sr, Ba, or combinations thereof, 0<x<1, and 0<y<1. Under excitation of blue light or ultraviolet light, the red phosphor emits red light having a major emission peak of about 613 nm. The red phosphor of the invention may be collocated with green and blue phosphors to provide a white light illumination device.

Claims

1. A red phosphor, comprising

M(Eu_1-x-yLa_xBi_y)₄Si₃O₁₃;

wherein M is Ca, Sr, Ba, or combinations thereof;

0<

x<

1; and

0<

y<

1.

2. The red phosphor as claimed in claim 1, wherein x ranges from 0.7 to 0.8, and y ranges from 0.03 to 0.10.

3. The red phosphor as claimed in claim 1, wherein x is about 0.75, and y is about 0.05.

4. The red phosphor as claimed in claim 1 is excited by an ultraviolet light of 393±

2 nm or a blue light of 460 nm.

5. The red phosphor as claimed in claim 1 is excited by a light emitting diode or a laser diode.

6. The red phosphor as claimed in claim 1 emits a red light having a major emission peak of 613 nm.

7. The red phosphor as claimed in claim 1 emits a red light having a color coordinate on a CIE scale, wherein the color coordinate has an x value of 0.63 to 0.64 and a y value of 0.34 to 0.35.

8. The red phosphor as claimed in claim 1 has a sintering temperature of about 1200 to 1400°

C. and a sintering time of about 8 to 12 hours.

9. A white light illumination device, comprising:

the red phosphor as claimed in claim 1;

a blue phosphor;

a green phosphor; and

an excitation light source.

10. The white light illumination device as claimed in claim 9, wherein the blue phosphor comprises BaMgAl₁₀O₁₇:

Eu²⁺ or ZnS;

Ag, Cl.

11. The white light illumination device as claimed in claim 9, wherein the green phosphor comprises BaMgAl₁₀O₁₇:

Eu²⁺, Mn²⁺ or ZnS;

Cu, Al.

12. The white light illumination device as claimed in claim 9, wherein the excitation light source is an ultraviolet light of 393±

2 nm or a blue light of 460 nm.

13. The white light illumination device as claimed in claim 9, wherein the excitation light source is a light emitting diode or a laser diode.