Birch, Stewart, Kolasch & Birch, LLP
Wide-angle catoptric system
A bright wide-angle catoptric system is provided which will not deteriorate the picture quality of images. The wide-angle catoptric system includes, successively from an object, a secondary reflecting mirror having a concave surface, a primary reflecting mirror having a convex surface and a tertiary reflecting mirror having a concave surface, and produces images by reflecting the luminous flux from the object at the primary reflecting mirror, the secondary reflecting mirror and the tertiary reflecting mirror successively. The system also includes a diaphragm arranged in close proximity to the primary reflecting mirror so as to have an optical axis pass through the center of the diaphragm; the optical axis is a straight line connecting the curvature center of the primary reflecting mirror to the curvature center of the secondary reflecting mirror. The tertiary reflecting mirror has its curvature center decentered from the optical axis in the direction of lesser astigmatism.
Mitsubishi Denki Kabushiki Kaisha
G
G02B
inventional
Takayuki Yasuhisa
Nakano Tamagawa