The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 12, 1990
Filed:
Jun. 20, 1989
William G Reed, Seattle, WA (US);
Maxwell G Maginness, Redmond, WA (US);
Ciba-Geigy Corporation, Ardsley, NY (US);
Abstract
A system for adjusting the density or contrast of a photographic print includes a projection lens system (18) for projecting an image from a negative (10) onto photosensitive paper (20). A matrix array (24) of liquid crystal display elements is interposed in the optical path in front of the print paper (20) and transmissivity of the individual LCD elements is controlled to provide an LCD mask to control the intensity and/or color of the light falling upon the print paper (20). Preferably, a television camera (16) is used with a beam splitter (14) to provide a real-time image of either the LCD mask (24) or the combined image of the mask (24) and negative (10) to allow adjustments in the mask (24) to be viewed as they are made. In printing black and white photos on multicontrast paper, the color transmissivity of the LCD elements is adjusted on an element-by-element basis to provide a localized adjustment of the contrast range of the print paper. Density and contrast can be simultaneously adjusted by controlling both the color balance and overall transmissivity of the LCD elements.