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. 17, 1984
Filed:
Dec. 14, 1981
Maurits W van Tol, Almelo, NL;
U.S. Philips Corporation, New York, NY (US);
Abstract
By causing the deflection of an electron beam (13) in a cathode-ray tube having a main system of deflection coils (4) and a system of post-deflection coils (5) to take place on the side of the display screen of the main system of deflection coils, which system of post-deflection coils causes a post-deflection of the electron beam opposite to the deflection by the main system of deflection coils which after deflection is synchronous with and weaker than the deflection by the main system of deflection coils, it is possible to choose the place of the (virtual) deflection point of the combination of main and post-deflection coil system more or less at will. By choosing L, the distance from said virtual deflection point to the display screen, to be substantially equal to 21, where l is the effective length of the overall magnetic deflection field, a substantially anastigmatic deflection sytstem is obtained.