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:
Feb. 19, 2002
Filed:
Dec. 21, 1998
George A. Melnick, Montrose, NY (US);
Ronald D. Pinker, Peekskill, NY (US);
Philips Electronics North America Corporation, New York, NY (US);
Abstract
A projection display device is provided which includes a border structure comprising a dam around the active display area of the device which both shields any underlying drive circuitry from the incidental light by reflecting this light-while passively controlling its birefringence such that this region appears dark to the viewer when no drive voltages are being applied. Preferably, the dam is positioned between the glue seal and the active region, the thickness of the dam being such as to allow a thin layer of LC material on top of the dam for compensated LC effects and in such case, the border structure between the glue seal and the active region is also effective to keep the glue from seeping into the active region when the seal line is squeezed during assembly. With a high birefringence material and an external compensation foil, a high degree of light extinction is achieved over the border. Also, formation of the border on the active plate means that no critical alignment of the passive plate is needed.