| 摘要 |
PROBLEM TO BE SOLVED: To provide an alignment apparatus capable of aligning a main mirror and sub mirror in the optical system with a simple constitution without substantially causing light quantity loss. SOLUTION: This alignment apparatus aligns the main mirror and sub mirror in the optical system having the main mirror 21 and sub mirror 22 arranged so that they face each other along the optical axis AX. The alignment apparatus includes a dichroic film 4 that is formed on the front-side surface of the sub mirror, reflects the used light of the optical system, and transmits the alignment light, a back-side reflecting surface 5 that is formed on the back side of the sub mirror and reflects the alignment light, and detecting systems 6, 7 and 8 for detecting the displacement of the main mirror from the sub mirror based on the alignment light that comes into the dichroic film of the sub mirror and is sequentially reflected by the back-side reflecting surface, the reflecting surface of the main mirror, and the back-side reflecting surface. COPYRIGHT: (C)2009,JPO&INPIT |
