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. 03, 2006
Filed:
Jan. 31, 2003
Applicants:
Kazuo Shikita, Tokyo, JP;
Tsutomu Nakashima, Tokyo, JP;
Nobuyuki Kimura, Tokyo, JP;
Inventors:
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G02F 1/1335 (2006.01);
U.S. Cl.
CPC ...
Abstract
A quarter wavelength plate for reducing the dependence of a retardation value on an incident beam angle in optically anisotropic crystals. The quarter wavelength plate is formed of optically anisotropic crystals in a thickness of 0.1 mm to 0.5 mm. The quarter wavelength plate can contribute to a reduction in the dependence of the retardation value on the angle at which a light beam impinges on the quarter wavelength plate, and to a reduction in color shading caused by a rise in temperature. A reflection type liquid crystal display device which employs the quarter wavelength plate can enhance the luminance and contrast.