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:
Dec. 15, 1992
Filed:
Nov. 08, 1991
Jayantilal S Patel, Red Bank, NJ (US);
Bell Communications Research, Inc., Livingston, NJ (US);
Abstract
A twisted ferroelectric liquid-crystal optical modulator in which a ferroelectric smectic C* liquid crystal (26) is filled into the gap between two alignment layers (18, 20) aligning the adjacent liquid crystal in two perpendicular directions parallel to the alignment layers. The ferroelectric liquid crystal has a tilt angle of 45.degree. and is aligned with the tilt angle parallel to the buffing direction of the alignment layer. Thereby, the liquid-crystal molecules (32), absent any applied field from electrodes (14, 18), slowly twists through 90.degree. across the gap, and the liquid crystal waveguides light linearly polarized by an input polarizer (22) so that it passes a perpendicularly arranged output polarizer (24). However, a strong electric field causes the ferroelectric molecules to untwist and line up in parallel. Waveguiding is destroyed, and the cell does not transmit. Intermediate voltages cause partial untwisting and partial waveguiding. Thus, variations in the applied voltages can modulate the light according to a gray scale.