Electronic camera with a view finder optical path switching device for selective transmission and reflection of light beam

Abstract

An electronic camera including a built-in strobe, an external strobe synchronization terminal, a photographic optical system, a prism, an imaging device, a viewfinder optical system, a light adjustment device, a movable mirror, and a drive source and drive circuit. External strobes are connected to the external strobe synchronization terminal so that they can be flashed synchronously with the built-in strobe. The prism splits a beam having passed through the photographic optical system. One portion of the split beam is converged on the imaging device to form an image thereon. The other portion of the split beam enters the viewfinder optical system. The light adjustment device detects the luminance of an object illuminated by the strobes. The movable mirror can selectively assume a position for transmitting a beam and a position for reflecting a beam. In the position for transmitting a beam, the movable mirror lies within the viewfinder optical system and routes a beam towards an eyepiece. In the position for reflecting a beam, the movable mirror reflects the beam towards the light adjustment device. The drive source and drive circuit displace the movable mirror. An amount of strobe light can be detected accurately by measuring the beam having passed through the photographic optical system. An image observed through the viewfinder does not appear dark.

Dependencies are inferred from the claim text.