| 摘要 |
PURPOSE:To surely secure the quantity of incident light to a finder and photo detector by obliquely providing a photo detecting mirror between focal plate and main mirror and disposing a distance measuring photo detector on its reflected light path. CONSTITUTION:A photo detecting mirror 8 consisting of a semilight transmittable mirror or nonlight-transmittable mirror is obliquely provided to the position of not cutting off the incident luminous flux to a film 7 between the focal plate 4 and main mirror 5 of the finder optical system. A distance measuring photo detector 3 is disposed on the reflected light path by this photo detecting mirror 8. As a result of this, the main mirror 5 is disposed on the incident light path to the film 7 and the incident light from the photographing lens 1 is imaged on the matt surface of the focal plate 4. At the same time, part of said image is changed of optical path by the photo detecting mirror 8 and is imaged on the distance measuring photo detector 3, whereby the distance measurement is acomplished. On the other hand, the main mirror 5 is retreated to the position of not interfering the incident luminous flux to the film 7 and the image is formed on the film 7, whereby exposure is done. |
