| 摘要 |
PROBLEM TO BE SOLVED: To reduce a bound of a sub-mirror and to prevent the deviation of a mirror-down position. SOLUTION: A mirror holding structure (30) includes: a main mirror holding frame (2) which holds a main mirror (1); a sub-mirror holding frame (4) which holds the sub-mirror (3) and is journaled by the main mirror holding frame (2); and a receiving pin (6) which comes into contact with the sub-mirror holding frame (4) in a mirror-down position, to determine the angle of the sub-mirror (3). The sub-mirror holding frame (4) includes: a first contact portion (4a) which comes into contact with the receiving pin (6) in the mirror-down position; and a second contact portion (4b) which comes into contact with the receiving pin (6) in a position before the mirror-down position when shifting from a mirror-up position to the mirror-down position is performed and is in a position different from the first contact portion (4a). COPYRIGHT: (C)2009,JPO&INPIT
|
