Illumination device and projector
View Patent ↗An illumination device includes a light source that emits light-source light, a light recovery member that is disposed close to the light source in the vicinity of a lateral side of the light source, and has a light receiving surface inclined at a predetermined angle with respect to an optical axis extending from the light source to the front to face the optical axis or the vicinity of the optical axis, and a rod integrator that uniformizes light-source light from the light source and light-source light reflected by the light recovery member.
1. An illumination device comprising:
a light source that emits light-source light;
a light recovery member that is disposed close to the light source in the vicinity of a lateral side of the light source, and has a light receiving surface inclined at a predetermined angle with respect to an optical axis extending from the light source, to face the optical axis;
a rod integrator that uniformizes light-source light from the light source and light-source light reflected by the light recovery member; and
a polarization separating element that is disposed at a rod emission port of the rod integrator;
the rod integrator having a plurality of step portions along the length of the rod integrator, the step portions reflecting light that is reflected off of the polarization separating element directly back towards the rod emission port of the rod integrator.
2. The illumination device according to claim 1 ,
wherein the light receiving surface of the light recovery member is a mirror that reflects light-source light emitted from the light source.
3. The illumination device according to claim 2 ,
wherein the mirror of the light recovery member is inclined at approximately 45° with respect to the optical axis.
4. The illumination device according to claim 1 ,
wherein the light source and the light recovery member are integrated to form a light source package.
5. The illumination device according to claim 1 ,
wherein the light recovery member is disposed in the vicinity of a light source package including the light source.
6. The illumination device according to claim 5 ,
wherein the light recovery member is fixed on a pedestal that supports the light source package.
7. The illumination device according to claim 6 ,
wherein the pedestal and the light recovery member are integrated to form a pedestal member.
8. The illumination device according to claim 1 ,
wherein the light recovery member has a fluorescent substance having photosensitivity to light-source light on the light receiving surface or in the vicinity of the light receiving surface.
9. The illumination device according to claim 1 ,
wherein a fluorescent substance provided in the light recovery member has a light-emission characteristic of at least one of yellow, green, and red light components relative to incident blue light.
10. The illumination device according to claim 1 ,
wherein the light recovery member causes a light flux to be emitted by reflection from the light recovery member to be incident on the rod integrator through a rod incident port, and causes the light flux to be directly emitted from the rod emission port of the rod integrator without being reflected in the rod integrator.
11. The illumination device according to claim 1 ,
wherein an aperture, through which a light flux is emitted from the light recovery member, is smaller than a rod incident port of the rod integrator.
12. The illumination device according to claim 11 ,
wherein the aperture of the light recovery member is disposed inwardly from the rod incident port of the rod integrator.
13. The illumination device according to claim 12 , further comprising:
an engagement unit that fixes the aperture of the light recovery member to the rod incident port of the rod integrator.
14. The illumination device according to claim 1 ,
wherein the polarization separating element is fixed to the rod emission port of the rod integrator.
15. The illumination device according to claim 1 ,
wherein the polarization separating element is a wire grid polarization element.
16. The illumination device according to claim 1 ,
wherein the step portions have a fluorescent substance having photosensitivity to light-source light.
17. A projector comprising:
the illumination device according to claim 1 ;
a light modulation device that modulates illumination light from the illumination device according to image information; and
a projection optical system that projects image light formed by the light modulation device.
18. The illumination device according to claim 1 ,
wherein the step portions are substantially perpendicular to the side of the rod integrator.