| 摘要 |
<p>PROBLEM TO BE SOLVED: To effectively use light of wavelengths other than visible rays which is not effectively used conventionally in a projector and an illuminating optical system. SOLUTION: In the projector provided with a light source and a lens for projection, a light-transmissive solar battery which absorbs light other than visible rays is arranged in an optical path, and power is generated in the light- transmissive solar battery by light from the light source. In the illuminating optical device, a light-transmissive solar battery which absorbs light other than visible rays is arranged in an optical path of radiant light from the light source, and power is generated in the light-transmissive solar battery by light from the light source. Or a light-transmissive solar battery which absorbs light other than visible rays is arranged on the surface of a reflector which reflects radiant light from the light source, and power is generated in the light-transmissive solar battery by light from the light source.</p> |
