| 摘要 |
PURPOSE:To omit a beam splitter and to manufacture the titled optical system easily and economically by providing a photographing optical system using a full reflecting prism and a range-finding light source projecting the light of a specific wavelength range. CONSTITUTION:The photographing optical path of the photographing optical system is refracted downwards by the full reflecting prism 11 arranged next to the front-group 10 of the photographing optical system and an image is formed by the rear-group 12 of the photographing optical system on an image pickup surface of an image pickup tube 13 for instance. An auxiliary prism 15 is arranged on the back of the full reflecting surface 14 of the full reflecting prism 11 and a projection lens 16 and a range-finding light source 17 are successively arranged on the back of the auxiliary prism 15. On the other hand, a photodetecting lens 18 and a photodetecting element 19 are arranged on the external part of the photographing optical system. Said constitution makes it possible to omit a beam splitter and to manufacture the optical system easily and economically. |
