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:
Apr. 24, 2001
Filed:
Oct. 28, 1998
Eizaburo Higuchi, Setagaya-ku, JP;
Yasuhiro Koike, Yokohama, Kanagawa, 225-0002, JP;
Other;
Abstract
An asymmetric prism sheet, surface light source and LCD to which the asymmetric prism sheet is applied is provided. A cold cathode tube backed by a reflector supplies light to an incidence surface of a directional emission guide plate. A polarization separation sheet and a liquid crystal panel are disposed outside of the asymmetric prism sheet, with the reflector disposed along a back face. First and second slopes of each asymmetric prism element rows have inclination angles &phgr;a, &phgr;b which are selected as to allow a secondary ray to exist inside a main ray emitted from a frontal face in a manner such that the main ray is deflected toward a generally frontal direction by way of internal reflection of the second slope while the secondary ray is deflected toward a generally frontal direction by way of double internal reflection of the first and second slopes. An outer face provides an uneven face such as non-glare-processed face, orthogonal prismatic face or lens face. Outside of an outer face may be arranged elements such as additional prism sheet or lens sheet.