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:
Nov. 01, 1988
Filed:
Jan. 22, 1987
Hisao Yokokura, Hitachi, JP;
Tadao Nakata, Katsuta, JP;
Susumu Era, Hitachi, JP;
Yasuo Hanawa, Katsuta, JP;
Kishiro Iwasaki, Hitachi-oota, JP;
Teruo Kitamura, Katsuta, JP;
Akio Mukoh, Mito, JP;
Toshikazu Narahara, Naka, JP;
Yasuhiko Kando, Mobara, JP;
Shunichi Numata, Hitachi, JP;
Kooji Fujisaki, Hitachi, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A liquid crystal display element comprising a pair of substrates, a pair of electrodes provided on the respective substrates, at least one of which is transparent and a liquid crystal layer disposed between said substrates, the liquid crystal layer comprising a nematic liquid crystal, which exhibits a positive dielectric constant anisotropy and contains an optically active substance, the liquid crystal moleccule orientation direction in the liquid crystal layer is twisted in the range of 200.degree. to 250.degree. from the one substrate surface toward the other substrate surface so as to form a helical structure therein. A polyimide orientation film is provided between the electrodes and the liquid crystal layer. The polyimide orientation film is one made of a polyimide prepared by reacting a diamine compound having a long-chain hydrocarbon group or a diamine compound having a trifluoromethyl group with a tetracarboxylic dianhydride and causes a pretilt angle of at least 3.degree. relative to the nematic liquid crystal molecules. The liquid crystal display element of the present invention is free from a scattering domain.