Focus detecting device in single lens reflex camera

摘要

A focus detecting device in a single lens reflex camera having a lens system and an optical image splitter for splitting an object image into various partial images disposed at a position optically equivalent to that of a film surface in said single lens reflex camera. An array of photo-electric conversion devices are arranged into at least two rows, each row having a plurality of photo-electric conversion elements. The rows are disposed symmetrically with respect to a center line. The device includes an image projecting device for projecting the partial images onto the photo-electric conversion arrays. The projecting device has an optical axis which optically corresponds to said center line, the output of said conversion array defined by The output of the conversion array has a maximum value when proper focus is obtained. In the equation: n is the number of said photo-electric conversion elements, p is the parameter of the mutual positional relationship of said photo-electric conversion elements for obtaining output difference, m is the element number of said photo-electric conversion elements, i and i' are outputs corresponding to incident light quantities of photo-electric conversion elements in said rows, and l is an integer defined by 1