| 摘要 |
<p>The domed housing (1) is sealed at the lower side by a thick perspex plate (2), and a thinner perspex plate (3), parallel to the thick one. The gap between the two plates are filled with glycerine. The purpose of the thinner plate (3) is to protect the thicker, e.g. 60 mm, plate (2). The optical axis (5) of the camera (4) passes through the pivoting axis (7) of a plane mirror (6). A motor (8) operates a toothed wheel to pivot the mirror (6), via a pawl arm (10). As the motor rotates once, the mirror pivots slowly through an arc four times, with rapid flyback. Any distortion caused by the differences in refractive indices can be compensated for by making the upper surface of the thick plate concave (2a).</p> |
