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:
Dec. 02, 1997
Filed:
Sep. 10, 1996
Kazuhiko Yanagawa, Mobara, JP;
Masayuki Ohta, Mobara, JP;
Kazuhiro Ogawa, Mobara, JP;
Keiichiro Ashizawa, Mobara, JP;
Kiyoshige Kinukawa, Chousei-gun, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A color liquid crystal display device includes a liquid crystal display panel having color filters corresponding to primaries red, green and blue, and a backlight unit disposed behind the liquid crystal display panel. The color liquid crystal display device satisfies a relationship of an isochromatic viewing angle>a half-brightness angle, for at least one azimuthal viewing angle. The half-brightness angle is defined as an angle of a direction inclined with respect to a normal direction of the liquid crystal display panel in which brightness of light emerging from the backlight unit into the liquid crystal display panel becomes 50% of that in the normal direction. The isochromatic viewing angle is defined as a range of viewing angles from the normal direction wherein an absolute shift in an x coordinate of the primary red viewed at off-normal angles is not greater than 0.0314, an absolute shift in a y coordinate of the primary green viewed at off-normal angles is not greater than 0.0273, and an absolute shift in an x coordinate of the primary blue viewed at off-normal angles is not greater than 0.0177, with respect to corresponding coordinates of corresponding primary colors of the primaries red, green and blue viewed in the normal direction, on the CIE 1931 chromaticity diagram.