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:
Dec. 30, 1980
Filed:
Nov. 16, 1978
Jorg Brambring, Eindhoven, NL;
Robert F van der Ven, Eindhoven, NL;
U.S. Philips Corporation, New York, NY (US);
Abstract
The haze around the electron beam spot in the corners and at the edge of the display screen is reduced by using in the electron gun a first grid of a construction such that a multipole lens which is mainly a first quadrupole lens is formed in cooperation with the cathode. The first grid in cooperation with the second grid also forms a multipole lens which is also a mainly second quadrupole lens and which is rotated 90.degree. with respect to the first quadrupole lens. Such a system of lenses in the first grid can be formed, for example, by providing in the first grid an aperture with elongated openings both on the side of the cathode and on the side of the second grid. The longitudinal axis of the elongated opening on the side of the cathode is substantially at right angles to the longitudinal axis of the elongated opening on the side of the second grid.