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:
Oct. 22, 1991
Filed:
Dec. 22, 1989
Kenneth R Skinner, Jefferson City, TN (US);
North American Philips Corporation, New York, NY (US);
Abstract
The contrast of a luminescent image produced by a CRT display device is improved by disposing a variable light transmissivity panel adjacent the CRT faceplate to intercept and attenuate ambient light reflected from the screen of the CRT. Control circuitry is provided to effect a decrease in the transmissivity of the panel in response to increasing ambient light intensity. The circuitry also effects an increase in the electron beam current with increasing ambient light intensity to increase the intensity of the luminescent image produced by the electron beam. When the device is not operating, the panel has a very low transmissivity causing the faceplate to appear dark.