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:
Oct. 02, 1990
Filed:
May. 18, 1989
Masanori Ogino, Yokohama, JP;
Takeo Yamada, Yokohama, JP;
Miyuki Ikeda, Yokohama, JP;
Toshiyuki Kimoto, Yokohama, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
The present invention relates to a miss convergence compensating circuit of a projection type display. The projection type display is provided with three projection tubes for red, green and blue colors and a color image is obtained by combining three colors from three projection tubes on a screen. When such projection tubes are arranged slant to the screen, miss convergence is generated on the screen. A convergence yoke for auxiliary deflection of electron beam is generally provided in order to compensate for such miss convergence, but this convergence yoke has the deflection sensitivity which is worse than that of deflection yoke. Therefore, the present invention contributes to compensate for miss convergence using the deflection yokes. For this purpose, at least two deflection coils are provided with a transformer coupling which allow the compensating currents corresponding to the miss convergence compensating signals to flow. In this case, the transformer coupling is coupled so that the currents of opposite polarities are caused to flow into at least two deflection coils as the compensating currents.