Method and apparatus for fabricating a translucent graded density membrane

Abstract

A method and apparatus for exposing a section of photographic medium such that it exhibits an incremental gradient in optical density across an area of the medium. A source of radiant energy is located in a container, which container is covered by a ground glass plate. This plate is covered by an opaque sheet, which sheet contains a narrow aperture. This sheet is covered by a second ground glass plate, such that the edge of the second plate overlies the edge of the aperture. A camera is focused on the surface of the opaque sheet. A portion of the light from the light source is diffused through the edge of the second plate and reflected toward the camera from the surface of the opaque sheet, causing the resultant image captured on the medium when the camera is activated to show a change in optical density with respect to the distance from the image on the medium of the edge of the second plate.

Dependencies are inferred from the claim text.