PHOTOGRAPHY SYSTEM WITH FOCUS DETECTING MEANS AND PHOTOMETRIC MEANS

摘要

PURPOSE:To simplify the whole device and to reduce its size by arranging a photodetection part which has plural thin film type thin-line photometric elements nearby an expected image formation plane or its conjugate position so that their thin lines and the shift direction of the secondary object image are parallel to each other. CONSTITUTION:Luminous flux from a subject which is passed through an image forming lens 2 is transmitted through the translucent surface of a quick-return mirror 7 and reflected by a small mirror 8 to form the primary object image nearby a distance measurement visual field 3. Then, the image is divided into two object images through a lens 10 for pupil image formation and a split prism 4 and re-formed as the secondary images on photodetecting element arrays 6-1 and 6-2 through a secondary image forming lens 5, and the photodetecting element arrays 6-1 and 6-2 detect the relative position relation between the secondary object images to perform the focus detection of the image forming lens 2. The photodetection part 15 is arranged in parallel to the lengthwise direction of the distance measurement visual field 3, namely, so that the array direction of the photodetecting element arrays 6-1 and 6-2 and the thin lines of the photometric elements are parallel, thereby performing focal plane light measurement without exerting any influence upon the focus detection.