Optical system for transmission of light

Abstract

Abstract PURPOSE:To prevent the conversion or diversion of light occurring in the change in the space between lenses on account of thermal expansion of an optical system for transmission of light with a change in temp. by inserting an intermediate lens in said optical system and holding said lens with materials having different coeffts. of expansion. CONSTITUTION:An intermediate lens 11 is inserted and disposed between an objective lens 1 and an eyepiece lens 2. The holding part 12 for the lens 11 is so made as to have the same coefft. of expansion as that of the 1st lens holding member 3. The part 12 is held by the 1st lens holding member 3 through the 2nd lens holding member 13 having a coefft. of expansion differing from that of the 1st lens holding member 3. Here, the coefft. of expansion of the 2nd member 13 is determined in accordance with the kinds, etc. of the lens 11, and the degradation in the parallelism of the transmitted light occurring in the change of the space between the lenses caused by thermal expansion in company with a change of temp. is prevented.

Inventors

• 👤 Kazumitsu Nakajima
• 👤 中島　一光

Bibliographic Details