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.

Date of Patent:
Jul. 06, 1993

Filed:

Dec. 10, 1990
Applicant:
Inventors:

Toshiyuki Kimoto, Yokohama, JP;

Miyuki Ikeda, Yokohama, JP;

Assignee:

Hitachi, Ltd., Tokyo, JP;

Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H03K / ; H03L / ;
U.S. Cl.
CPC ...
307228 ; 307261 ; 307263 ; 307264 ; 307271 ; 307491 ; 328 35 ; 328127 ; 328181 ;
Abstract

Electric charges are stored on a capacitor and then the charges are discharged so that a sawtooth wave for use in a convergence correction circuit for a display or the like is generated. When the sawtooth wave is used for a multi-scan display, the charge period is varied according as the scanning frequency varies, and as a result, a phase error is produced in the parabolic wave obtained by squaring the sawtooth wave. To eliminate the phase error, it is adapted such that the discharging current from the capacitor is passed through a coil and, in addition, the period as the reciprocal of the resonant frequency of the resonance circuit formed of the coil and the capacitor is set to be virtually double the discharge period.


Find Patent Forward Citations

Loading…