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:
Aug. 27, 1996
Filed:
Mar. 15, 1995
Philip J Bos, Beaverton, OR (US);
Tektronix, Inc., Wilsonville, OR (US);
Abstract
A color liquid crystal display (LCD) includes many ones of a color cell triad (150) of liquid crystal cells (80R, 80G, 80B) and a negative birefringence compensator plate (110). The color cell triads are positioned between a pair of linear polarizers (112, 114), and each color cell triad is in optical association with colored filters (152R, 152G, 152B). Each of the liquid crystal cells has a symmetrical director field (82, 82') that produces a symmetrical but nonuniform color viewing circle curve (100) from the liquid crystal cell. The negative birefringence plate restores the color viewing angle uniformity. When graphed on a polar plot, the measured light transmission percentage curves (120, 122, 124) characterizing the LCD are substantially concentric circles surrounding the optical axis (18) for all azimuthal angles (28) and viewing angles (24) up to 30 degrees. Thus, the color LCD provides a multi-color display having colors that are perceptibly uniform over a wide range of azimuthal and viewing angles.