| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a film thickness monitoring device capable of simultaneously solving problems of conventional reflection type and transmission type film thickness monitoring devices, and effectively enhancing the film thickness monitoring accuracy. <P>SOLUTION: The film thickness monitoring device to monitor the thickness of an optical thin film vapor-deposited on an optical substrate fixed to a surface of a clamp mechanism includes at least one light source to emit beams passing through the optical thin film along a first path, at least one retro-reflector which is installed on another side of the light source facing the clamp mechanism, reflects the beams, and makes the beams pass through the optical thin film again along a second path parallel to the first path, and at least one light receiver to receive the beams passed through the optical thin film along the second path. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
