Optical apparatus including a light modulation finder optical system

摘要

An optical apparatus includes a projection optical system for projecting an object image; a focal detection system for detecting a defocus state of the object image with respect to a photosensitive plane by a light emitted from the projection optical system; a finder system for observing the object by the light emitted from the projection optical system, the finder system being provided with a light modulation unit for creating a light transmission state when electric energy is input and a cutoff state when electric energy is not input, and the light modulation unit being disposed so as to cover the view field of the finder system; and a control unit for controlling input of the electric energy to a light modulation unit, the control unit controlling so as not to input electric energy when the user does not look through the finder system.