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. 28, 1998
Filed:
Apr. 24, 1995
Casio Computer Co., Ltd., Tokyo, JP;
Abstract
A birefringence control type color liquid crystal display device includes a liquid crystal cell having first and second substrates; first and second electrodes formed on opposing surfaces of the first and second substrates; a first aligning film formed on the first electrode and subjected to an aligning treatment in a first direction; a second aligning film formed on the second electrode and the second substrate and subjected to an aligning treatment in a second direction intersecting the first direction at 90 degrees; and a liquid crystal sealed between the first and second aligning films and twisted at 90 degrees. The device further includes a first polarization plate arranged outside of the second substrate and having a transmission axis intersecting the first direction at substantially 140 to 160 degrees; a second polarization plate arranged outside of the first substrate and having a transmission axis intersecting the transmission axis of the first polarization plate at substantially 10 to 40 degrees; a first retardation plate arranged between the second substrate and the second polarization plate, with a direction of a maximum refraction index intersecting the first direction at 130 to 160 degrees; and a second retardation plate arranged between the second substrate and the second polarization plate, with a direction of a maximum refraction index intersecting the first direction at substantially 40 to 80 degrees.