| 摘要 |
PROBLEM TO BE SOLVED: To provide simple and inexpensive constitution by which an image forming position by an optical path division means is corrected without inserting optical parts for correction. SOLUTION: A QR half mirror 3 capable of retreating while rocking through a shaft 3a at the time of photographing and an imaging device 5 are arranged behind an objective lens group (1 and 2). The terrestrial telescope with a digital camera is provided with an observation optical system (6 to 9) for observing an image reflected by the mirror 3 at the time of observation. The transmission surface of the mirror 3 on the imaging device 5 side is constituted of a correction surface to correct the image forming positions on the imaging device 5 when the mirror 3 is inserted and when it is detached to be nearly equal, for example, a toroidal surface having different curvature between in a vertical surface direction and in a horizontal surface direction, whereby the image forming position by the mirror 3 is corrected. Then, the toroidal surface is arranged to be eccentric from an optical axis so as to correct image forming shift in a direction crossing with the optical axis. COPYRIGHT: (C)2005,JPO&NCIPI |
