REFERENCE POSITION ADJUSTING DEVICE, OPTICAL DEVICE, AND OPTICAL APPARATUS

摘要

PROBLEM TO BE SOLVED: To accurately determine the reference position of a light shielding body or optical component at all times. SOLUTION: A reference position adjusting device is equipped with a light emitting means, a light receiving means facing the light emitting means, and a level detecting means detecting the output level of the light receiving means and adjusts the reference position of the light shielding body according to variation in the output level of the light receiving means by shielding the light receiving means from the light from the light emitting means by the movement of the light shielding body capable of reciprocating in specified directions. The reference position adjusting device uses the level detecting means to detect as a non-light shielding level the output level of the light receiving means when the light from the light emitting means is not cut off by the movement of the light shielding body and regards as the reference position the position of the light shielding body when the output level reaches a specified ratio to the non- light shielding level by partially shielding the light receiving means from the light from the light emitting means by the movement of the light shielding body.