Production of Uniform Hard Copy From Display
Original Publication Date: 1985-Feb-01
Included in the Prior Art Database: 2005-Feb-18
This article relates to the production of uniform hard copy by the illumination of a passive display of the kind in which light images are formed on a black background. In such a system, the use of a cheap and simple illumination and imaging system results in variations in intensity across the image. The intensity variations are removed from the hard copy output by using a stored map of the intensity variations and adjusting the exposure of the film over a series of multiple exposure steps. A suitable display for such a system is a light-scattering electrolytic display of the kind described in Applied Physics Letters 42, 911-913 (1983). The image brightness of this display depends on the intensity and angle of illumination and on the collection efficiency of the imaging lens.