Illumination system multi-layered wavelength-converting device

Patent metadata

Field	Value
Publication number	US-9696013-B2
Application number	US-201514755378-A
Country	US
Kind code	B2
Filing date	Jun 30, 2015
Priority date	Sep 5, 2014
Publication date	Jul 4, 2017
Grant date	Jul 4, 2017

Abstract

An illumination device includes a solid-state light-emitting element, and a wavelength-converting device with a transmissive substrate, a phosphor layer and a reflective optical layer. The transmissive substrate has a refraction coefficient n s greater than an ambient refraction coefficient n amb . The phosphor layer is disposed over a side of the transmissive substrate and the reflective optical layer is disposed over a side of the transmissive substrate opposite to the phosphor layer. The reflective optical layer has an effective refraction coefficient n r . The relation between n s , n amb and n r is given by n r >2(n amb 2 )/n s .

First claim

What is claimed is:

1. A wavelength-converting device used for converting first waveband light, comprising:
a transmissive substrate having opposite first and second sides, and a refraction coefficient n s greater than an environmental refraction coefficient n amb ;
a phosphor layer disposed over the first side of the transmissive substrate for converting the first waveband light into second waveband light; and
an optical layer disposed over the second side of the transmissive substrate for reflecting the second waveband light, wherein the optical layer has an effective refraction coefficient n r , such that n r >2(n amb 2 )/n s .

2. The wavelength-converting device according to claim 1 , wherein the optical layer is configured for reflecting both the first waveband light and the second waveband light.

3. The wavelength-converting device according to claim 1 , wherein the transmissive substrate is selected from the group consisting of sapphire substrate, a glass substrate, a borosilicate glass substrate, a borofloat glass substrate, a fused quartz substrate and a calcium fluoride substrate.

4. The wavelength-converting device according to claim 1 , wherein the optical layer comprises at least metallic material having silver or aluminum.

5. The wavelength-converting device according to claim 1 , wherein the optical layer comprises a silver alloy or an aluminum alloy.

6. The wavelength-converting device according to claim 1 , wherein the optical layer comprises a distributed Bragg reflector or an omnidirectional reflector.

7. The wavelength-converting device according to claim 1 , wherein the optical layer is configured for transmitting the first waveband light and reflecting the second waveband light.

8. The wavelength-converting device according to claim 7 , wherein the first waveband light is blue light or ultraviolet light, and the second waveband light comprises visible light with wavelength greater than 460 nanometers.

9. An illumination system, comprising:
a solid-state light-emitting element configured for emitting first waveband light in an optical path; and
a wavelength-converting device disposed on the optical path, comprising:
a transmissive substrate having opposite first and second sides, and a refraction coefficient n s greater than an environmental refraction coefficient n amb ;
a phosphor layer disposed over the first side of the transmissive substrate for converting the first waveband light into second waveband light and outputting the second waveband light; and
an optical layer disposed over the second side of the transmissive substrate for reflecting the second waveband light, wherein the optical layer has an effective refraction coefficient n r , such that n r >2(n amb 2 )/n s .

10. The illumination system according to claim 9 , wherein the wavelength-converting device is a reflective wavelength-converting device, and the solid-state light-emitting element is disposed closer to the phosphor layer than to the optical layer.

11. The illumination system according to claim 9 , wherein the wavelength-converting device is a transmissive wavelength-converting device, and the solid-state light-emitting element is disposed closer to the optical layer than to the phosphor layer.

Assignees

• Delta Electronics Inc

Inventors

• Chang Keh-Su
• Chen Jau-Shiu
• Chou Yen-I
• Chen Chi

Classifications

• F21V14/08

  by movement of the screens {or filters} · CPC title

• G02B26/008

  in the form of devices for effecting sequential colour changes, e.g. colour wheels · CPC title

• F21V13/08 Primary

  the elements being filters or photoluminescent elements and reflectors · CPC title

• H01L33/50

  Electricity · mapped topic

• H10H20/851 Primary

  Wavelength conversion means · CPC title