Patent ID: 7692708
Filing Date: 2010-04-06
Classification: G03B

Abstract:
1. A photometric apparatus having at least two photometric sensors, comprising: a single incidence optical system, on which a light bundle forming an object image, which has passed through a focusing screen and an image erecting system, is incident; a beam splitting optical system which splits said light bundle which is incident on said single incidence optical system, into at least two light bundles, said beam splitting optical system comprising an incident surface, a beam splitting surface, a first emitting surface from which a light bundle passing through the beam splitting surface is emitted, and a second emitting surface from which a light bundle reflected by the beam splitting surface is emitted; a first photometering optical system provided on the first emitting surface which directs the light bundle emitted from the first emitting surface to a first photometric sensor; and a second photometering optical system provided on the second emitting surface which directs the light bundle emitted from the second emitting surface to a second photometering sensor, wherein said single incidence optical system and said first and second photometering optical systems are configured to serve as an optical system via which the object image is projected onto the first and second photometric sensors, magnifications of said first and second photometering optical systems are the same as each other so that the sizes of object images projected onto said first and second photometric sensors are identical with each other, each of said first and second photometric sensors comprises a split photometric sensor which operates to measure brightness of object images formed on split sensing areas of said split photometric sensor, and an insensitive area of one of said two split photometric sensors, which isolates said split sensing areas from one another, is formed to be substantially the same in shape and size as one of said split sensing areas of the other of said two split photometric sensors.