| 摘要 |
PURPOSE:To enable a tilt angle of a partial reflecting mirror to be regulated by a biaxial swinging operation easily and rapidly, by providing two tilt angle regulating means between a mirror holder and a body, so that these two means regulate a tilt angle of the mirror holder in different directions from each other. CONSTITUTION:A distance between a mirror holder 2 and a holding ring 10b secured to a body 1 is held by a tilt angle regulating means having a coil spring 8a and a setscrew 7a. Another set-screw 7b is engaged similarly at a position on a flange 3b rotated by 90 deg. with respect to the setscrew 7a. One end of the coil spring 8b inserted and held at the other end of the holding ring 10b is applied against a part of the flange 3b opposing to the setscrew 7b across a center hole 3a approximately on the same circumference. Accordingly, a distance between the mirror holder 2 and the holding ring 10b secured to the body 1 is held also by a second tilt angle regulating means having the coil spring 8b and the setscrew 7b. |
