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:
Nov. 30, 1993
Filed:
Feb. 03, 1992
Applicant:
Inventor:
Fridolin Wiget, Neuchatel, CH;
Assignee:
Asulab S.A., Neuchatel, CH;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G02F / ;
U.S. Cl.
CPC ...
359 85 ; 359 38 ;
Abstract
An optical cell having an optically active material, for example a liquid crystal is disclosed, the transparency of which is a function of the electrical voltage applied together with a control circuit, wherein said optically active material presents an electrical impedance variable with the frequency of the signal applied and said control circuit has a voltage source and means for controlling the frequency of the signal delivered by said voltage source. The cell has applications in attenuating light, notably in a sun screen or automobile rear-view mirror.