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. 05, 2004
Filed:
Apr. 10, 2002
Jing-Jong Pan, Milpitas, CA (US);
Xiangdong Qiu, Cupertino, CA (US);
Hai-Ming Wu, Milpitas, CA (US);
Lightwaves 2020, Inc., Milpitas, CA (US);
Abstract
A temperature compensation circuit arrangement for liquid crystal cells in optical devices is presented. In an optical device, a liquid crystal cell typically manipulates the optical signals according to an output optical property, such as attenuation, responsive to an AC voltage source electrical signal. A feedback circuit arrangement is connected to the liquid crystal cell and controls the current through the liquid crystal cell with respect to temperature by a predetermined control equations for the output optical property so that the device manipulates the optical signals independently of temperature. The current follows the control equations, which are empirically determined with respect to temperature for one equation.