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. 31, 1989
Filed:
Sep. 29, 1987
Otto Mensies, Eindhoven, NL;
U.S. Philips Corporation, New York, NY (US);
Abstract
Display tube such as a projection television display tube or a DGD tube (DGD=Data Graphic Display), including an electron gun (5) in an evacuated envelope (1) for generating an electron beam (6) which is focussed to a spot (8) on a display screen (7) with the aid of an electrostatic focussing lens (27, 30) and which is deflected across the display screen (7) in two mutually perpendicular directions (x, y). If a correction structure (37) consisting of magnetic half-hard material is provided in such a tube in the proximity of the focussing lens (27, 30) and coaxially of the gun axis (20) in which at least one magnetic 2N pole (N.gtoreq.2) is induced for correcting spot shape errors, a high spot quality can be realized with low-cost deep-drawn lens electrodes (27, 30).