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. 12, 1993
Filed:
Oct. 28, 1991
Terence K Gibbs, Stubbington, GB;
Graham Luck, Chichester, GB;
International Business Machines Corporation, Armonk, NY (US);
Abstract
Linearity correction apparatus for a raster scanned cathode ray tube display device is presented. The apparatus comprises first means (16) for generating a correction signal to correct an asymmetric non linearity in a sawtooth electron beam line deflection current. The line deflection current is generated by a line timebase circuit for energising electromagnetic electron beam deflection coils of the cathode ray tube. The apparatus further comprises second means (70,90,91) cooperative with the first means (16) and responsive to a change in line timebase frequency for compensating a variation in the correction signal generated by the first means (16) in response to said change in line timebase frequency.