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:
Nov. 25, 1986
Filed:
May. 14, 1984
Aart A Van Gorkum, Eindhoven, NL;
U.S. Philips Corporation, New York, NY (US);
Abstract
A cathode ray tube comprising in an evacuated envelope (1) an electron gun system (5,104) for generating at least one electron beam (6,7,8,105) which is focused on a target (10,108) by means of at least one accelerating electron lens (22,23,50,51). The lens viewed in the direction of propagation of the electron beam, comprises a first (22,50) and a second (23,51) electrode separated by a lens gap (30,53). In the second electrode is an electrically conductive foil or gauze (31,52) intersects the beam at a distance from the lens gap. When the foil or gauze is flat and is provided at such a location that 0.25<l/R<2.0, where l is the distance from the foil or gauze to the lens gap and R is the radius of the part of the second electrode in which or against which the foil or gauze is provided. The spherical aberration in the electron beam is drastically reduced. Such a flat gauze moreover is easy to manufacture and assemble in an electron gun.