Compact light engine

Patent metadata

Field	Value
Publication number	US-9470398-B2
Application number	US-201314415763-A
Country	US
Kind code	B2
Filing date	Jul 22, 2013
Priority date	Jul 23, 2012
Publication date	Oct 18, 2016
Grant date	Oct 18, 2016

Abstract

A light engine comprises: a wavelength conversion device, receiving source light of a first wavelength range and a first polarisation, generating light of a second wavelength range from a portion of the received source light, at least a portion of the second wavelength range being non-overlapping with the first wavelength range, the wavelength conversion device reflects output light comprising the generated light and comprises a polarisation converter that sets at least some of the output light to a second polarisation, different from the first polarisation; and a dichroic element, that receives the reflected output light and directs light of the first polarisation differently from light of the second polarisation.

First claim

The invention claimed is:

1. A light engine, comprising:
a wavelength conversion device, arranged to receive source light of a first wavelength range and a first polarisation, to generate light of a second wavelength range from a portion of the received source light, at least a portion of the second wavelength range being non-overlapping with the first wavelength range, the wavelength conversion device being further arranged to reflect output light comprising the generated light, wherein the wavelength conversion device comprises (i) a disc portion and (ii) a polarisation converter configured to set at least some of the output light to a second polarization that is different from the first polarisation; and
a dichroic element, arranged to receive the reflected output light, the dichroic element being configured to direct light of the first polarisation differently from light of the second polarization, the polarisation converter being located between the disc portion and the dichroic element.

2. A light engine, comprising:
a wavelength conversion device, arranged to receive source light of a first wavelength range and a first polarisation and configured selectively to generate light of a second wavelength range from a portion of the received source light, the second wavelength range being different from the first wavelength range, the wavelength conversion device being further arranged to reflect output light comprising the generated light, wherein the wavelength conversion device comprises (i) a disc portion and (ii) a polarisation converter configured to set at least some of the output light to a second polarisation that is different from the first polarisation;
an actuator, configured to cause motion of the wavelength conversion device, to select generation of light of the second wavelength range thereby; and
a dichroic element, arranged to receive the reflected output light, the dichroic element being configured to direct light of the first polarisation differently from light of the second polarisation, the polarisation converter being located between the disc portion and the dichroic element.

3. The light engine of claim 2 , wherein at least a portion of the second wavelength range is non-overlapping with the first wavelength range.

4. The light engine of claim 1 , wherein the dichroic element is further arranged to direct the source light to be incident upon the wavelength conversion device.

5. The light engine of claim 1 , wherein the wavelength conversion device is configured to reflect a portion of the received source light, the output light thereby comprising the generated light of the second wavelength range and reflected source light of the first wavelength range.

6. The light engine of claim 5 , wherein the polarisation converter is configured to set the reflected source light of the first wavelength range to the second polarisation.

7. The light engine of claim 5 , wherein the dichroic element is configured to direct light of the first wavelength range and first polarisation differently from light of the first wavelength range and second polarisation.

8. The light engine of claim 1 , wherein the dichroic element is configured to direct light of the first wavelength range and first polarisation differently from light of the second wavelength range.

9. The light engine of claim 8 , wherein the dichroic element is configured to pass light of the first wavelength range and first polarisation and to reflect light of the first wavelength range and second polarisation and light of the second wavelength range.

10. The light engine of claim 8 , wherein the dichroic element is configured to reflect light of the first wavelength range and first polarisation and to pass light of the second wavelength range and light of the first wavelength range and second polarisation.

11. The light engine of claim 1 , wherein the second wavelength range is substantially non-overlapping with the first wavelength range.

12. The light engine of claim 11 , wherein the wavelength conversion device comprises a phosphor element to generate light of the second wavelength range.

13. The light engine of claim 1 , wherein the wavelength conversion device is a wheel, a first portion of the surface of the disc portion being configured to generate light of the second wavelength range.

14. The light engine of claim 1 , wherein the wavelength conversion device is further configured to generate light of a third wavelength range from a portion of the received source light.

15. The light engine of claim 14 , wherein the wavelength conversion device is a wheel, a first portion of the surface of the disc portion being configured to generate light of the second wavelength range and a second portion of the surface of the disc portion being configured to generate light of the third wavelength range.

16. The light engine of claim 13 , wherein a portion of the surface of the disc portion is configured to reflect light of the first wavelength range.

17. A light engine, comprising a dichroic element arranged to cause source light of an initial polarisation to be incident upon a phosphor wheel that comprises (i) a disc portion and (ii) a polarisation converter, some of the source light being converted into light of a different color, some of the source light being reflected without a color change but with a change in polarisation and wherein the converted light and reflected source light are incident upon the dichroic element, the dichroic element being configured to direct the reflected source light differently than the source light of the initial polarisation, wherein the polarisation converter is between the dichroic element and the disc portion.

18. The light engine of claim 1 , further comprising:
a light source, arranged to provide the source light.

19. A projector comprising the light engine of claim 1 .

20. A method of generating light, comprising:
passing source light of a first wavelength range and a first polarisation through a dichroic element to be received at a wavelength conversion device that comprises (i) a disc portion and (ii) a ploarisation converter;
generating light of a second wavelength range at the wavelength conversion device from a portion of the received source light, at least a portion of the second wavelength range being non-overlapping with the first wavelength range, the wavelength conversion device therefore providing output light that comprises the generated light;
setting the polarisation of at least some of the output light to a second polarisation that is different from the first polarisation using the polarisation converter; and
reflecting the output light from the wavelength conversion device towards the dichroic element, the dichroic element being configured to direct light of the first polarisation differently from light of the second polarisation, wherein the polarisation converter is between the dichroic element and the disc portion.

21. A method of generating light, comprising:
receiving source light of a first wavelength range and a first polarisation at a wavelength conversion device that comprises (i) a disc portion and (ii) a polarisation converter;
selectively generating light of a second wavelength range at the wavelength conversion device from a portion of the received source light, the second wavelength range being different from the first wavelength range, the wavelength conversion device therefore providing output light that comprises the generated light;
moving the wavelength conversio

Assignees

• Cao Simon
• Chen Louis
• Bai Shengyuan
• Materion Corp

Inventors

• Cao Simon
• Chen Louis
• Bai Shengyuan

Classifications

• F21V9/45

  by adjustment of photoluminescent elements · CPC title

• F21V13/08

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

• G02B27/286

  for controlling or changing the state of polarisation, e.g. transforming one polarisation state into another (G02B5/3083 takes precedence; light guide coupling means utilising polarising elements G02B6/34) · CPC title

• G03B21/204

  using secondary light emission, e.g. luminescence or fluorescence (using different colours G03B33/00; if related to video signals H04N9/3197) · CPC title

• F21V7/04

  Optical design · CPC title