| 摘要 |
PROBLEM TO BE SOLVED: To provide a Schmidt Cassegrain cata-dioptric system capable of reducing spherical aberration without complicating the constitution. SOLUTION: As for the Schmidt Cassegrain cata-dioptric system constituted of a primary mirror, a secondary mirror and a Schmidt plate, at least one of the primary mirror and the secondary mirror is constituted of a rear face mirror. By increasing the number of refraction times and increasing the degree of freedom at designing in such the way, the spherical aberration due to different kinds of wave length generated on the Schmidt plate can be corrected. Besides, as for the rear face mirror, it is required for the refractive lens only to make the rear face the reflection face, then, the weight increase is suppressed as compared with a conventional Schmidt Cassegrain optical system. COPYRIGHT: (C)2003,JPO
|
