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:
Oct. 31, 2000
Filed:
Nov. 28, 1997
Chorum Technologies, Inc., Richardson, TX (US);
Abstract
A hybrid analog/binary electro-optic modulator using a twisted ferroelectric liquid crystal structure is provided. Ferroelectric liquid crystals with a tilt angle of between about 20.degree. and about 25.degree., preferably about 22.5.degree. are used. Rubbing directions for the two cell walls (relative to one another) can be varied from about 45.degree. to about 90.degree.. In one embodiment, a weak buffing force is used resulting in a relatively weak anchoring energy at the surface, aligning the liquid crystal molecules without locking the molecules into the buffing directions and a high pre-tilt structure for the molecules close to the surface boundaries. In one embodiment, strong buffing is used with buffing directions offset about 45.degree.. Use of this invention provides relatively fast response time, low required driving voltage, high contrast, and/or the ability to achieve both analog and binary operations.