Adjustable photographic device
AssigneeArriflex Corporation
InventorsVolker W. Bahnemann, Stanislaw Loth
Life of this patent
Estimating the term…
Abstract
An adjustable photographic device includes a light transmission element for allowing light from an object to be photographed to pass therethrough, and light sources positioned around the periphery of the light transmission element for introducing light into the periphery of the light transmission element. This light introduced into the periphery of the light transmission element is internally reflected in the light transmission element causing the contrast of the photographed image to be controlled or modified without effecting the resolution thereof.
Claims29
An adjustable photographic device, comprising:
- light transmission means for allowing light from an object to be photographed to pass through a front surface and a rear surface thereof, said light transmission means having a peripheral portion;
- and
- means for introducing a variable amount of light into said peripheral portion of said light transmission means so that rays of said variable amount of light meet said front and rear surfaces at angles greater than the critical angle of said light transmission means and are thereby internally reflected by said front and rear surfaces within said light transmission means so as to adjust contrast of the object to be photographed without effecting resolution thereof.
A contrast indicator comprising:
- a plurality of optical glass means, each having a peripheral portion and a front and a rear surface, wherein a first and a second separated area on said front surface are ground;
- a plurality of neutral optical density filters, having different darknesses, mounted, respectively, on the front surfaces of said optical glass means over said respective second separated areas;
- nontransparent white screening means arranged on the back surfaces of each of said plurality of optical glass means in an area corresponding to said first separated area;
- nontransparent black screening means arranged on the back surfaces of each of said plurality of optical glass means in an area corresponding to said second separated area;
- and
- means for introducing a variable amount of light into said peripheral portion of a selected one of said optical glass means so that said light is internally reflected in said selected optical glass means thereby illuminating said ground first and second separated areas and also adjusting a contrast range of a scene to be photographed, whereby a desired contrast range is achieved by observing a black portion of the scene and adjusting the amount of light introduced into said selected optical glass means using said light introducing means until the black portion of the scene corresponds to the second separated area on said optical glass means.
Dependencies are inferred from the claim text.