Phosphor blend for wavelength conversion and white light emitting device using the same

• US 20060221635A1
• Filed: 12/28/2005
• Published: 10/05/2006
• Est. Priority Date: 03/30/2005
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electro-Mechanics Co., Ltd. (Samsung Group)
• Inventors: Yoon, Chul Soo, Yoon, Joon Ho, Sohn, Jong Rak, Kwak, Chang Hoon, Chung, Yun Seup, Park, Il Woo
• Granted Patent: US 7,911,127 B2
• Time in Patent Office: Days
• US Class Current: 362/612
• CPC Class Codes: C09K 11/7731 with alkaline earth metals
• CPC Class Codes: C09K 11/77342 Silicates
• CPC Class Codes: C09K 11/7739 with halogens
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/48257 connecting the wire to a die pad of the item
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 33/502 Wavelength conversion materials
• CPC Class Codes: H01L 33/504 Elements with two or more wavelength conversion materials
• CPC Class Codes: Y02B 20/00 Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps

Abstract

The present invention relates to phosphor blend for wavelength conversion and a white light emitting device using the same. The phosphor blend of the invention comprises three phosphors, A₅ (PO₄)₃Cl:Eu²⁺, D₂SiO₄:Eu, and MS:Eu at a composition where near ultraviolet radiation is converted into light positioned at a CIE coordinate (x, y),where 0.25≦x≦0.45 and 0.25≦x≦0.43, wherein A comprises at least one of Sr, Ca, Ba, and Mg, D comprises at least one of Ba, Sr, and Ca, and M comprises at least one of Sr and Ca. Furthermore, the present invention provides a new white light emitting device in combination of the phosphor blend and a near ultraviolet LED.

Claims

1. Phosphor blend for wavelength conversion comprising three phosphors, A₅(PO₄)₃Cl:

Eu²⁺, D₂SiO₄;

Eu, and MS;

Eu, wherein A comprises at least one of Sr, Ca, Ba, and Mg, D comprises at least one of Ba, Sr, and Ca, and M comprises at least one of Sr and Ca.

2. The phosphor blend for wavelength conversion according to claim 1, wherein near ultraviolet radiation is converted into light positioned within a triangular area having CIE coordinates of (0.15, 0.03), (0.19, 0.63) and (062, 0.37) in CIE chromaticity diagram.

3. White light emitting phosphor blend comprising three phosphors, A₅(PO₄)₃Cl:

Eu²⁺, D₂SiO₄;

Eu, and MS;

Eu at a composition where near ultraviolet radiation is converted into light positioned at a CIE coordinate (x, y),where 0.25≦

x≦

0.45 and 0.25≦

x≦

0.43, wherein A comprises at least one of Sr, Ca, Ba, and Mg, D comprises at least one of Ba, Sr, and Ca, and M comprises at least one of Sr and Ca.

4. The white light emitting phosphor blend according to claim 3, wherein the output light has a color rendering index of 80 or more with respect to the near ultraviolet radiation.

5. The white light emitting phosphor blend according to claim 4, wherein A₅(PO₄)₃Cl:

Eu²⁺is contained in an amount of 40 to 88 wt %, D₂SiO₄;

Eu is contained in an amount of 10 to 58 wt %, and MS;

Eu is contained in an amount of 2 to 50 wt %.

6. The white light emitting phosphor blend according to claim 3, wherein the output light has a color rendering index of 90 or more with respect to the near ultraviolet radiation.

7. The white light emitting phosphor blend according to claim 6, wherein A₅(PO₄)₃Cl:

Eu²⁺is contained in an amount of 70 to 83 wt %, D₂SiO₄;

Eu is contained in an amount of 13 to 27 wt %, and MS;

Eu is contained in an amount of 3 to 7 wt %.

8. White light emitting phosphor blend containing three phosphors, A₅(PO₄)₃Cl:

Eu , D₂SiO₄;

Eu, and MS;

Eu, where A comprises at least one of Sr, Ca, Ba, and Mg, D comprises at least one of Ba, Sr, and Ca, and M comprises at least one of Sr and Ca, and wherein A₅(PO₄)₃Cl;

Eu²⁺is contained in an amount of 40 to 88 wt %, D₂SiO₄;

Eu is contained in an amount of 10 to 58 wt %, and MS;

Eu is contained in an amount of 2 to 50 wt %.

9. The white light emitting phosphor blend according to claim 8, wherein A₅(PO₄)₃C1:

EU²⁺is contained in an amount of 70 to 83 wt % of, D₂SiO₄;

Eu is contained in an amount of 13 to 27 wt %, and MS;

Eu is contained in an amount of 3 to 7 wt %.

10. A white light emitting device comprising:

a light emitting diode (LED) for emitting near ultraviolet radiation; and

a wavelength converting part placed in the light emission direction of the LED, and having white light emitting phosphor blend and curing resin wherein the white light emitting phosphor comprises three phosphors, A₅(PO₄)₃Cl;

Eu²⁺, D₂SiO₄;

Eu and MS;

Eu, at a composition where near ultraviolet radiation is converted into light positioned at a CIE coordinate (x, y), where 0.3≦

x≦

0.45 and 0.3≦

x≦

0.43, wherein A comprises at least one from Sr, Ca, Ba and Mg, D comprises Ba, Sr and Ca, and M comprises at least one of Sr and Ca.

11. The white light emitting device according to claim 10, wherein the near ultraviolet LED emits radiation having a wavelength of 300 to 450 nm.

12. The white light emitting device according to claim 10, wherein the curing resin comprises silicon or epoxy resin.

13. The white light emitting device according to claim 10, wherein the output light has a color rendering index of 80 or more.

14. The white light emitting device according to claim 13, wherein A₅(PO₄)₃Cl:

Eu²⁺is contained in an amount of 40 to 88 wt %, D₂SiO₄;

Eu is contained in an amount of 10 to 58 wt %, and MS;

Eu is contained in an amount of 2 to 50 wt %.

15. The white light emitting device according to claim 10, wherein the output light has a color rendering index of 90 or more.

16. The white light emitting device according to claim 15, wherein A₅(PO₄)₃Cl:

Eu²⁺is contained in an amount of 70 to 83 wt %, D₂SiO₄;

Eu is contained in an amount of 13 to 27 wt %, and MS;

Eu is contained in an amount of 3 to 7 wt %.