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:
Mar. 10, 1992
Filed:
Jul. 24, 1990
Hitachi, Ltd., Tokyo, JP;
Abstract
An apparatus and method for driving an optical printer having at least one liquid crystal optical switch including a ferroelectric liquid crystal layer interposed between a pair of substrates having electrodes on confronting surfaces thereof, the at least one liquid crystal switch being disposed between a light source and a photosensitive surface, a light transmission state of the at least one liquid crystal optical switch being controlled by application of a voltage signal to the at least one liquid crystal optical switch so as to control light transmission to the photosensitive surface. A first voltage signal is applied to the liquid crystal of at least one liquid crystal optical switch in a writing period in which the light transmission state is determined in accordance with a printing signal for printing. A second voltage signal having a DC component of one polarity is applied to the liquid crystal layer in a retention period. A third voltage signal having a DC component of an opposite polarity is applied to the liquid crystal layer in a reset period in which the at least one liquid crystal optical switch is placed in a light interrupting state, and a fourth voltage signal having a DC component of the one polarity is applied to the liquid crystal layer in a period other than an excluding period which is formed of the writing period, the retention period and the reset period.