Light source device and projection display apparatus
The light source device of the projection display apparatus according to the present disclosure includes: solid-state light sources that individually emit blue light, green light, and red light; a plurality of dichroic mirrors that combine the blue light, the green light, and the red light having exited from the solid-state light sources; a first diffusion plate on which the combined light having been combined by the plurality of dichroic mirrors is incident; a dynamic diffusion plate that is disposed at a position at which the combined light having exited from the first diffusion plate converges and starts to diverge.
1. A light source device, comprising:
solid-state light sources that individually emit blue light, green light, and red light;
a plurality of dichroic mirrors that combine, into combined light, the blue light, the green light, and the red light having exited from the solid-state light sources;
a first diffusion plate on which the combined light having been combined by the plurality of dichroic mirrors is incident;
a dynamic diffusion plate that is disposed at a position at which the combined light having exited from the first diffusion plate converges and starts to diverge; and
a second diffusion plate on which the combined light having exited from the dynamic diffusion plate is incident, the combined light being divergent light.
2. The light source device according to claim 1 , wherein the plurality of dichroic mirrors is configured including:
an either red-reflection or green-reflection dichroic mirror on which collimated light is incident; and
a blue-reflection dichroic mirror on which convergent light is incident.
3. The light source device according to claim 2 , wherein the blue-reflection dichroic mirror is a film-thickness-distributed dichroic mirror.
4. The light source device according to claim 1 , wherein the dynamic diffusion plate is a rotary diffusion plate including:
a circular diffusion plate that has a glass substrate with a surface in which a fine concave-and-convex structure is formed in an annular-ring shape; and
a motor that rotates the circular diffusion plate.
5. The light source device according to claim 1 , wherein the first diffusion plate is a diffusion plate having a glass substrate on which a microlens array is formed.
6. The light source device according to claim 1 ,
wherein the solid-state light sources include a solid-state light source that emits the blue light; and
the solid-state light source is a blue semiconductor laser.
7. The light source device according to claim 1 ,
wherein the solid-state light sources include a solid-state light source that emits the green light; and
the solid-state light source is a green semiconductor laser.
8. The light source device according to claim 1 ,
wherein the solid-state light sources include a solid-state light source that emits the red light; and
the solid-state light source is a red semiconductor laser.
9. The light source device according to claim 1 , wherein the blue light, the green light, and the red light exiting from the solid-state light sources are each linearly-polarized light.
10. The light source device according to claim 1 , wherein the combined light exiting from the dynamic diffusion plate is linearly-polarized light.
11. A projection display apparatus, comprising:
the light source device according to claim 1 , the light source device emitting light;
an illumination optical system that converges the light having exited from the light source device;
an image forming element that is illuminated with the light having exited from the illumination optical system, and forms an image in accordance with an image signal; and
a projection lens that enlarges and projects the image formed by the image forming element.
12. The projection display apparatus according to claim 11 , wherein the image forming element is a liquid crystal panel.
13. The projection display apparatus according to claim 11 , wherein the image forming element is a mirror-deflection digital micromirror device.