Camera having a diffusing plate with rotationally asymmetric light diffusion property
AssigneeCanon Kabushiki Kaisha
InventorsTetsuro Kuwayama, Takashi Suzuki, Kazuya Matsumoto
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Abstract
A photographic camera provided with a finder system having, at the focal plane of the imaging lens, a light diffusing plate having a rotationally asymmetric diffusion property or a rotationally asymmetric angular distribution of diffused light. Such a camera is provided with a photosensor for light measuring therewithin. The diffusing plate diffuses light so that the photosensor receives an appropriate quality of light, and so that the light is distributed in the manner that the operator can easily focus the camera.
Claims10
A camera having a diffusing plate with a rotationally asymmetric light diffusion property comprising;
- an imaging lens forming a first optical path,
- a finder optical system forming a second optical path,
- a photosensitive member positioned at a focal plane in said first optical path,
- a diffusing plate positioned at a focal plane in said second optical path and having a rotationally asymmetric angular distribution property,
- a photo detecting means positioned out of the optical axis of said second optical path, and
- an exposure control means.
A camera having a diffusing plate with a rotationally asymmetric light property comprising:
- an imaging lens forming an image of an object,
- a photosensitive member positioned at a focal plane of said imaging lens,
- a finder optical system for observing the object,
- a diffusing plate positioned at a second focal plane in said finder optical system and diffusing the incident light parallel to the optical axis of said finder optical system with a rotationally asymmetric angular distribution property in which the angular distribution in one plane including said incident light is different from that in another plane perpendicular to said one plane and including said incident light.
A camera having a diffusing plate with a rotationally asymmetric distribution property comprising:
- an imaging lens forming an image of an object,
- a finder optical system for observing the object,
- a diffusing plate positioned at a focal plane of said imaging lens and having an arrangement of a plurality of lenslets each of a rotational asymmetric surface which has different powers in two perpendicular planes.
Dependencies are inferred from the claim text.