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:
Jan. 23, 2001
Filed:
Sep. 28, 1998
Matthias Thomas Peter Pfeiffer, Mesa, AZ (US);
Dan J. Schott, Phoenix, AZ (US);
Joseph Hourigan Morrissy, Phoenix, AZ (US);
Three-Five Systems, Inc, Tempe, AZ (US);
Abstract
A method of modifying the polarization state of light exiting a Liquid Crystal Display that is effected without altering the optical image of the display comprises reducing the select voltage to the LCD cell to less than the saturation select voltage. In one embodiment of an apparatus incorporating features of the present invention, a color LCD display is constructed using two or more LCD cells that are aligned to produce an optimum image through the display optics. One or more of the LCD cells are then driven to the dark state at a select voltage that is less than the saturation select voltage for that cell. By operating the LCD cell at less than the saturation select voltage, the polarization state of the light exiting a dark selected pixel compensates for the misalignment between the saturation voltage polarization axis of the display and the system polarization axis of the optics. Accordingly, the selected pixel appears darker than would the same pixel driven at the saturation voltage. By operating the LCD cell at less than the saturation select voltage, higher contrast ratios and improved color saturation is achieved without sacrificing image quality.