Light source device and projection-type display apparatus
A light source device includes: blue, green, and red laser light sources; a first retardation plate that controls polarization of blue laser light emitted from the blue laser light source; a polarizing beam splitter that separates the blue laser light whose polarization is controlled by the first retardation plate into a first blue laser light and a second laser light; a second retardation plate that controls polarization of the second blue laser light separated by the polarizing beam splitter; a fluorescent plate that is excited by the first blue laser light separated by the polarizing beam splitter and emits fluorescent light including a green component and a red component; a first dichroic mirror that combines the second blue laser light whose polarization is controlled by the second retardation plate and light emitted from the green and red laser light sources, to generate combined laser light; a dynamic diffuser plate that diffuses the combined laser light combined by the first dichroic mirror to generate diffused laser light; and a second dichroic mirror that combines the diffused laser light diffused by the dynamic diffuser plate and the fluorescent light emitted from the fluorescent plate.
1. A light source device comprising:
a blue laser light source;
a green laser light source;
a red laser light source;
a fluorescent plate that is excited by a part of the blue laser light and emits fluorescent light including a green component and a red component;
a first dichroic mirror that combines another part of the blue laser light, green laser light emitted from the green laser light source, and red laser light emitted from the red laser light source, to generate combined laser light;
a second dichroic mirror that combines the combined laser light and the fluorescent light emitted from the fluorescent plate,
wherein the generated combined laser light does not enter the fluorescent plate before being combined with the fluorescent light emitted from the fluorescent plate by the second dichroic mirror.
2. The light source device according to claim 1 further comprising:
a first retardation plate that controls polarization of blue laser light emitted from the blue laser light source.
3. The light source device according to claim 2 further comprising:
a polarizing beam splitter that separates the blue laser light whose polarization is controlled by the first retardation plate into a first blue laser light and a second blue laser light.
4. The light source device according to claim 2 ,
wherein the first retardation plate is a half-wavelength plate.
5. The light source device according to claim 2 , wherein the first retardation plate is rotationally adjusted to adjust a ratio between two polarization components orthogonal to each other.
6. The light source device according to claim 3 , wherein the polarizing beam splitter is a flat plate-shaped polarization beam splitter.
7. The light source device according to claim 3 further comprising:
a second retardation plate that controls polarization of the second blue laser light separated by the polarizing beam splitter.
8. The light source device according to claim 7 , wherein the second retardation plate is a half-wavelength plate that converts a polarization direction.
9. The light source device according to claim 1 further comprising:
a dynamic diffuser plate that diffuses the combined laser light combined by the first dichroic mirror to generate diffused laser light.
10. The light source device according to claim 1 , wherein the fluorescent plate is a rotation-controllable circular substrate, and includes a phosphor layer formed of a Ce:YAG based yellow phosphor.
11. The light source device according to claim 1 , wherein the blue laser light source, the green laser light source, and the red laser light source are semiconductor lasers.
12. A projection-type display apparatus comprising:
a light source;
an illumination optical system that condenses light emitted from the light source and illuminates an area to be illuminated;
an image forming element that forms an image, based on a video signal; and
a projection lens that enlarges and projects the image formed by the image forming element, wherein the light source is the light source device according to claim 1 .
13. The projection-type display apparatus according to claim 12 , wherein the image forming element is a liquid crystal panel.
14. The projection-type display apparatus according to claim 12 , wherein the image forming element is a mirror-deflection-type digital micromirror device (DMD).
15. The light source device according to claim 1 ,
wherein the fluorescent plate is excited only by the part of the blue laser light and not by any portion of the generated combined laser light.