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. 11, 1995
Filed:
May. 18, 1993
Norio Matsuda, Tsurugashima, JP;
Pioneer Electronic Corporation, Tokyo, JP;
Abstract
A photoconductive type liquid crystal valve maintains good gradation contrast characteristics in a projection image irrespective of if and when a possible temperature change occurs. The photoconductive type liquid crystal light valve comprises a laminated body including a liquid crystal layer 15, a photoconductive layer 15, and a light shielding layer 17, and a pair of driving electrodes which sandwich the laminated body and form an image forming area. A pair of temperature detecting electrodes are provided at positions out of the image forming area to sandwich at least the light shielding layer and detect a change in impedance of the light shielding layer, thereby detecting a temperature change of the light valve. By changing the level of a driving voltage signal which is supplied to the driving electrode on the basis of the detected temperature change, the gradation characteristics and contrast can be held constant from the time point of the initial setting of the black level even when the temperature fluctuates.