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:
May. 21, 1996
Filed:
May. 08, 1995
Leonard P Wilbur, Jr, Lancaster, PA (US);
Owen H Roberts, Jr, Landisville, PA (US);
Thomson Consumer Electronics, Inc., Indianapolis, IN (US);
Abstract
An apparatus (38) for rapidly and uniformly electrostatically charging a photoconductive layer (34) disposed on a conductive layer (32) provided on an interior concave surface of a viewing faceplate (18) of a CRT faceplate panel (12) is disclosed. The apparatus includes a housing (40) having a faceplate panel support surface (42), an electrical contact (52) for grounding the conductive layer, a corona charger (48), and power supplies (200, 204) for corona charging. The corona charger (48) includes a charging head (46) that substantially conforms to the contour of the interior concave surface of the viewing faceplate (18). The charging head comprises a base plate (54) having a mounting surface (56) to which a plurality of discrete charging modules (82) are attached. Each of the charging modules includes a focusing blade (86) and a charging blade (88, 188) insulated from the focusing blade. An ultimate focusing blade (186) is attached to the ultimate discrete charging module. The dimensions of the charging head are slightly less than the interior dimensions of the faceplate panel. The first power supply applies a first voltage to each of the charging blades and a second power supply applies a second voltage to each of the focusing blades. The apparatus further includes a motor (210) with an eccentric cam (212) that is connected by a shaft (214) to the charging head for laterally moving the charging head within the faceplate panel for a distance substantially equal to the periodic spacing (P) between charging blades of adjacent discrete charging modules, thereby providing a substantially uniform electrostatic charge to the photoconductive layer on the viewing faceplate.