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:
Jan. 15, 1991
Filed:
Aug. 31, 1988
Yasuyuki Takiguchi, Kawasaki, JP;
Akihiko Kanemoto, Yokohama, JP;
Kenya Yokoi, Yokohama, JP;
Haruo Iimura, Yokohama, JP;
Takamichi Enomoto, Shiroyama, JP;
Sumio Kamoi, Kawasaki, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
A liquid crystal display device, comprising: (a) a liquid crystal layer disposed between a pair of light permeable substrates, an alignment of a liquid crystal of said liquid crystal layer being substantially horizontal relative to said substrates in the absence of applied voltage, said liquid crystal layer having a twisted structure with a twist angle along a direction of a thickness thereof such that an adequate display is provided without substantially reducing the time dimensional driving; (b) a pair of polarization means disposed on both outsides of said liquid crystal layer; and (c) at least one birefringent medium layer disposed between one side of said liquid crystal layer and the polarization means on said one side of said liquid crystal layer; an optical axis of said birefringent medium layer being inclined toward a polarization axis of the adjacent polarization means, the alignment direction of said liquid crystal on a surface of another side of said liquid crystal layer making an angle from 0.degree. to 25.degree. relative to the polarization transmission axis or an absorption axis of the polarization means, the direction of a maximum refractive index of said birefringent medium layer and the alignment direction of said liquid crystal on a surface of said one side of said liquid crystal layer on a surface of said one side of said liquid crystal layer making an angle from 20.degree. to 130.degree. while a retardation of said birefringent medium layer is in a range of 0.125 .pi.rad to 1 .pi.rad and a retardation of said liquid crystal layer is about 3/2 .pi.rad or about 2 .pi.rad.