METHOD FOR DETERMINING MIXTURE COMPOSITION OF FLUORESCENT MATERIALS AND METHOD FOR MANUFACTURING LIGHT-EMITTING DEVICE

• US 20080106734A1
• Filed: 10/30/2007
• Published: 05/08/2008
• Est. Priority Date: 10/30/2006
• Status: Active Grant

• Current Assignee: Kyocera Corporation
• Original Assignee: Kyocera Corporation
• Inventors: KATABE, Kousuke
• Granted Patent: US 7,728,970 B2
• Time in Patent Office: Days
• US Class Current: 356/317
• CPC Class Codes: H01L 2933/0041 relating to wavelength conversion elements
• CPC Class Codes: H01L 33/50 Wavelength conversion elements
• CPC Class Codes: H01L 33/504 Elements with two or more wavelength conversion materials

Abstract

A method for determining a mixture composition of a plurality of fluorescent materials includes steps of calculating a first function, calculating a second function and determining a secondary mixture composition of the plurality of fluorescent materials. The first function is calculated by comparing an objective spectrum of an objective light with a reference spectrum of a reference light. The second function is calculated by comparing a primary spectrum of the plurality of fluorescent materials mixed at a primary mixture with the reference spectrum composition. The secondary mixture composition is determined on the basis of the result of comparison between the first function and the second function.

Claims

1. A method for determining a mixture composition of a plurality of fluorescent materials being excited by light emitted from a light-emitting chip made of a semiconductor material, the method comprising:

calculating a first function by comparing an objective spectrum of an objective light with a reference spectrum of a reference light;

calculating a second function by comparing a primary spectrum of the plurality of fluorescent materials mixed at a primary mixture composition with the reference spectrum; and

determining a secondary mixture composition of the plurality of fluorescent materials on the basis of the result of comparison between the first function and the second function.

2. The method according to claim 1, wherein the calculating the first function comprises:

calculating a first plurality of light intensities corresponding to a plurality of test colors, in the reference light; and

calculating a second plurality of light intensities corresponding to the plurality of test colors, in the objective light.

3. The method according to claim 2, wherein the calculating the first function further comprises calculating a first plurality of relative values of the second plurality of light intensities with respect to the first plurality of light intensities.

4. The method according to claim 3, wherein the calculating the second function comprises calculating a third plurality of light intensities corresponding to the plurality of test colors, in a light emitted from the plurality of fluorescent materials mixed at the primary mixture composition.

5. The method according to claim 4, wherein the calculating the second function further comprises calculating a second plurality of relative values of the third plurality of light intensities with respect to the first plurality of light intensities.

6. The method according to claim 2, wherein the plurality of test colors includes CIE test colors.

7. The method according to claim 6, wherein the plurality of test colors includes the CIE test colors R1 to R8.

8. The method according to claim 2, wherein the plurality of test colors includes a general color rendering index.

9. The method according to claim 2, wherein the first plurality of light intensities and the second plurality of light intensities are calculated by a method of specifying color rendering properties defined by JIS Z 8726.

10. The method according to claim 1, wherein the reference light has a color temperature of 2800 K.

11. The method according to claim 1, wherein the reference light is the CIE standard illuminant D65.

12. A method for manufacturing a light-emitting device including a light-emitting chip made of a semiconductor material, the method comprising:

determining a secondary mixture composition of a plurality of fluorescent materials on the basis of a first function and a second function, the first function denoting a relative relationship between a reference light and an objective light, the second function denoting a relative relationship between the reference light and a light emitted from the plurality of fluorescent materials mixed at a primary mixture composition;

preparing a light emitter including the plurality of fluorescent materials on the basis of the secondary mixture composition;

mounting the light-emitting chip on a base; and

placing the light emitter on or above the light-emitting chip.

13. The method according to claim 12, wherein the first function is calculated by comparing an objective spectrum of the objective light with a reference spectrum of the reference light.

14. The method according to claim 13, wherein the second function is calculated by comparing a primary spectrum of the plurality of fluorescent materials mixed at a primary mixture composition with the reference spectrum.

15. The method according to claim 12, wherein the preparing the light emitter includes mixing the plurality of fluorescent materials on the basis of the secondary mixture composition.

16. The method according to claim 15, wherein the preparing the light emitter further includes putting the plurality of fluorescent materials mixed on the basis of the secondary mixture composition in a transparent materials.