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:
Apr. 21, 1992
Filed:
Jul. 25, 1990
Jan Gerritsen, Eindhoven, NL;
U.S. Philips Corporation, New York, NY (US);
Abstract
A cathode ray tube, such as a blue luminescing projection television display tube including, in an evacuated envelope (1), an electron gun (5) for generating an electron beam (6) which is focused to a spot (8) on a display screen (7) by means of an electrostatic focusing lens (27, 30) and which is deflected across this display screen (7) in two mutually perpendicular directions (x, y). A structure (37) magnetized as a four-pole and consisting of a magnetic half-hard material is provided at the area of a focusing lens formed by two electrodes (27, 30) and coaxially around the gun axis (20), the axes of the four-pole being located centrally between the deflection directions. The structure (37) extends the spot in the vertical direction so that phosphor saturation, particularly in blue projection tubes is reduced.