Rangefinding device for camera

摘要

A rangefinding device for a camera, in which a light projecting unit for projecting near-infrared light to an object and a light receiving unit for receiving object-reflected light reflected from an object are provided in such a manner as to be nearly in parallel with each other. The light receiving unit is provided with: a prism having a total reflection surface for reflecting almost all of object-reflected light having been incident thereon; and a light receiving element for receiving object-reflected light that is reflected by this total reflection surface of the prism. Further, the total reflection surface of the prism is formed so that a sum of an angle of incidence and an angle of reflection of object-reflected light reflected by the total reflection surface of this prism is greater than 90 DEG degrees.