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. 06, 1999
Filed:
Oct. 10, 1997
Koichi Kajimoto, Tenri, JP;
Takeshi Seike, Kitakatsuragi-gun, JP;
Sharp Kabushiki Kaisha, Osaka, JP;
Abstract
In a liquid crystal display device of the present invention, a white plate light source such as a cool cathode fluorescent tube is provided on a back surface of a liquid crystal cell, i.e., on a surface opposite to a displaying surface of the liquid crystal cell. On a surface opposite to the displaying surface of the liquid crystal panel, a polarizing plate-equipped semitransmitting reflecting plate is provided. The liquid crystal panel is composed of active elements such as MIM (Metal-Insulator-Metal) elements or TFTs (Thin Film Transistors). With this arrangement, discharge of a charge is suppressed by switching of the active element when a voltage is applied to two types of electrodes sandwitching a liquid crystal layer. By setting reflectance and transmittance of the polarizing plate-equipped semitransmitting reflecting plate such that contrast of the liquid crystal panel is higher when the cool cathode fluorescent tube is not lighted than when the cool cathode fluorescent tube is lighted, it is ensured that visibility both in a reflecting mode and a transmitting mode are improved.