Patent ID: 7226171

Claim:
An optical device which includes an optical modulator forming an optical image by modulating a light beam irradiated from a light source in accordance with image information, comprising: an optical modulator holder having a cooling chamber, in which a cooling fluid is sealed therein, for holding said optical modulator in a thermally conductive state for the cooling fluid in said cooling chamber; a plurality of fluid circulating members communicated to said cooling chamber of said optical modulator holder for guiding said cooling fluid to the outside of said cooling chamber and again guiding said cooling fluid to the inside of said cooling chamber; and a cooling fluid accumulating section provided in a flow path of said cooling fluid of said plurality of fluid circulating members for accumulating therein said cooling fluid, wherein said cooling fluid accumulating section comprises an upstream-side cooling fluid accumulating section provided in the upstream of said cooling fluid against said optical modulator holder and a downstream-side cooling fluid accumulating section provided in the downstream of said cooling fluid against said optical modulator holder, wherein said optical modulator holder includes a pair of frame members each having an opening formed therein corresponding to an image forming region of said optical modulator and a light-transmissible substrate provided on either one of the sides of said openings opposite to the sides where said pair of frame members are opposed to each other for closing either one of the sides of said openings opposite to the sides where said pair of frame members are opposed to each other, wherein said optical modulator is held between said pair of frame members for closing the sides of said opening where said pair of frame members are opposed to each other, and wherein either one of said pair of frame members is formed with an inlet port for flowing said cooling fluid inside and an outlet port for flowing said cooling fluid outside, both communicating to said plurality of fluid circulating members, and said cooling chamber is formed for sealing said cooling fluid by closing the sides of said opening where said pair of frame members are opposed to each other and the sides of said openings opposite to the sides where said pair of frame members are opposed to each other respectively with said optical modulator and said light-transmissible substrate.