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:
Mar. 21, 1989
Filed:
Aug. 12, 1987
Applicant:
Inventors:
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01J / ; H01J / ;
U.S. Cl.
CPC ...
315368 ; 315370 ;
Abstract
A convergence apparatus in which a sawtooth wave signal having a horizontal period is modulated by a sawtooth wave signal having a vertical period and supplied to a convergence coil to correct misconvergence of rasters on the projection screen, characterized in that the sawtooth wave signal having the horizontal period is derived by integrating a pulse advanced in phase as compared with the flyback pulse by a PPL circuit and hence the distortion of the sawtooth wave signal having the horizontal period exists within a horizontal blanking period.