Light source unit and projector

Patent metadata

Field	Value
Publication number	US-9983468-B2
Application number	US-201615189166-A
Country	US
Kind code	B2
Filing date	Jun 22, 2016
Priority date	Aug 26, 2015
Publication date	May 29, 2018
Grant date	May 29, 2018

Abstract

To provide a light source unit which can be formed compact in size while contributing to enhancement in luminance and a projector including this light source unit, there is provided a light source unit including a first light source which emits light in a range of first wavelengths, and a second light source which emits light in a range of second wavelengths which is different from the range of first wavelengths, wherein the first light source and the second light source each include a long wavelength light emitting portion and a short wavelength light emitting portion, the long wavelength light emitting portion emitting, of lights of different wavelengths which exist in a range of light wavelengths producing light of similar colors, light of a long wavelength, the short wavelength light emitting portion emitting light of a short wavelength.

First claim

What is claimed is:

1. A light source unit comprising:
a first light source which emits light in a range of first wavelengths and comprises a long wavelength light emitting portion and a short wavelength light emitting portion, the long wavelength light emitting portion emitting light of a long wavelength side in a range of wavelengths producing light of similar colors, and the short wavelength light emitting portion emitting light of a short wavelength side in the range of wavelengths producing light of similar colors;
a second light source which emits light in a range of second wavelengths which is different from the range of first wavelengths and comprises a long wavelength light emitting portion and a short wavelength light emitting portion, the long wavelength light emitting portion emitting light of a long wavelength side in a range of wavelengths producing light of similar colors, and the short wavelength light emitting portion emitting light of a short wavelength side in the range of wavelengths producing light of similar colors; and
a light source controller having a plurality of modes, one of the plurality of modes being a mode for causing only respective long wavelength light emitting portions of the first light source and the second light source to be illuminated.

2. The light source unit according to claim 1 ,
wherein the first light source and the second light source each comprise a plurality of long wavelength light emitting portions like the long wavelength light emitting portion and a plurality of short wavelength light emitting portions like the short wavelength light emitting portion which are disposed alternately into a matrix configuration in which the long wavelength light emitting portions and the short wavelength light emitting portions are arranged into a plurality of rows and a plurality of columns.

3. The light source unit according to claim 1 ,
wherein the long wavelength light emitting portion and the short wavelength light emitting portion of the first light source and the long wavelength light emitting portion and the short wavelength light emitting portion of the second light source are arranged so that light emitted from the long wavelength light emitting portion of the first light source and light emitted from the long wavelength light emitting portion of the second light source are disposed at positions where they correspond to each other and that light emitted from the short wavelength light emitting portions of the first light source and light emitted from the short wavelength emitting portion of the second light source are disposed at positions where they correspond to each other.

4. The light source unit according to claim 1 ,
wherein an arrangement of the long wavelength light emitting portion and the short wavelength light emitting portion in a row direction of the first light source and an arrangement of the long wavelength light emitting portion and the short wavelength light emitting portion in a row direction in the second light source are symmetrical with each other.

5. The light source according to claim 1 ,
wherein the light source controller has further a mode in which the long wavelength light emitting portion and the short wavelength light emitting portion of the first light source and the long wavelength light emitting portion and the short wavelength light emitting portion of the second light source are illuminated altogether.

6. The light source according to claim 1 ,
wherein a light source of the first light source and a light source of the second light source are made up of a semiconductor light emitting element.

7. The light source unit according to claim 1 ,
wherein light in the range of first wavelengths of the first light source is light in a range of red wavelengths, and light emitted from the long wavelength light emitting portion and light emitted from the short wavelength light emitting portion of the first light source are red light and amber light, respectively, and
wherein light in the range of second wavelengths of the second light source is light in a range of blue wavelengths, and light emitted from the long wavelength light emitting portion and light emitted from the short wavelength light emitting portion of the second light source are blue light and purple light, respectively.

8. The light source unit according to claim 1 , comprising:
an excitation light source; and
a luminescent plate device comprising a luminescent plate which emits luminous light in a range of green wavelengths as a result of excitation light being shone on to the luminescent plate from the excitation light source.

9. The light source unit according to claim 8 ,
wherein the excitation light source includes a plurality of blue laser diodes,
wherein the plurality of blue laser diodes are disposed so that when a projection is carried out in a second mode in which only the long wavelength light emitting portions of the first light source and the second light source are illuminated, an axis of light emitted from the long wavelength light emitting portion of the first light source, an axis of light emitted from the long wavelength light emitting portion of the second light source and an axis of a pencil of luminous light emitted in a luminescent fashion from the luminescent plate as a result of a green luminescent material in the luminescent plate being excited by excitation light shone from the plurality of blue laser diodes overlap one another.

10. The light source unit according to claim 8 ,
wherein the excitation light source includes a plurality of blue laser diodes, and
wherein the number of blue laser diodes is increased or decreased according to the numbers of long wavelength light emitting portions of the first light source and the second light source.

11. The light source unit according to claim 9 ,
wherein the excitation light source includes a plurality of blue laser diodes, and
wherein the number of blue laser diodes is increased or decreased according to the numbers of long wavelength light emitting portions of the first light source and the second light source.

12. The light source unit according to claim 8 ,
wherein the excitation light source includes a plurality of blue laser diodes, and
wherein when a projection is carried out in a second mode in which only the long wavelength light emitting portions of the first light source and the second light source are illuminated, the light source controller controls the plurality of blue laser diodes in such a way that some blue laser diodes of the plurality of blue laser diodes are illuminated so that an axis of light emitted from the long wavelength light emitting portion of the first light source, an axis of light emitted from the long wavelength light emitting portion of the second light source and an axis of a pencil of luminous light emitted in a luminescent fashion from the luminescent plate as a result of a green luminescent material in the luminescent plate being excited by excitation light shone from the plurality of blue laser diodes overlap one another.

13. The light source unit according to claim 8 ,
wherein the excitation light source is driven according to the luminance of the first light source and the second light source.

14. A projector comprising:
the light source unit according to claim 1 ;
a display device on to which light source light from the light source unit is shone to thereby form image light;
a projection-side optical system which projects the image light emitted from the display device on to a screen; and
a projector controller which controls the display device and the light source

Assignees

• Casio Computer Co Ltd

Inventors

• Ogino Hiroshi

Classifications

• H04N9/3164

  using multiple light sources · 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

• G03B21/2033

  LED or laser light sources · CPC title

• G03B21/2013 Primary

  Plural light sources · CPC title

• G03B33/04

  by four or more separation records · CPC title