Patent ID: 7866827

Claim:
An optical device, comprising: a plurality of optical elements; a base which supports the plurality of optical elements; and a plurality of element holders which can hold the plurality of optical elements and each includes a holder side flow passage for cooling liquid to flow therein, the plurality of element holders holding the plurality of optical elements to connect the plurality of optical elements and the cooling liquid flowing in the holder side flow passage in a heat transferable manner, wherein the base includes a plurality of plate members which are layered on each other to form at least one base side flow passage for the cooling liquid to flow therein, the plurality of element holders and the base can be connected to each other, so that the holder side flow passage and the at least one base side flow passage communicate with each other, the plurality of element holders each include a holder side connector to be in communication with the holder side flow passage and connected to the base, the base includes a plurality of base side connectors to be in communication with the at least one base side flow passage and connected to the plurality of element holders, and the holder side connector and the plurality of base side connectors are connected to each other, so that the holder side flow passage communicates with the at least one base side flow passage and the plurality of optical elements held by the plurality of element holders are positioned at predetermined positions relative to the base.