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:
Jul. 07, 1987
Filed:
Jul. 13, 1984
Johan Andrea, Eindhoven, NL;
Eugene Lubchenko, Knoxville, TN (US);
Ralph H Bradley, Kingsport, TN (US);
NAP Consumer Electronics Corp., New York, NY (US);
U.S. Philips Corporation, New York, NY (US);
Abstract
In a color picture projection system three monochrome pictures are superimposed to form a color display on a projection screen by means of a chromatic projection lens system in each of three channels. Each channel has a reflector to fold the light path. Since at least one monochrome picture (e.g. the blue picture) includes radiation within a desired band of wavelengths corresponding to its associated color and radiation outside of this desired band, the reflector in this channel is wavelength-selective and reflects only the radiation within the desired band towards the projection screen. The undesired radiation is transmitted through the reflector so that it does not reach the projection screen. Achromatic lenses are therefore not required.