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:
May. 20, 1986
Filed:
May. 08, 1984
Joe A Mays, Xenia, OH (US);
Systems Research Laboratories, Inc., Dayton, OH (US);
Abstract
In a dual mode CRT deflection circuit, a capacitor for effecting rapid retrace of the CRT beam by means of resonant nonlinear operation is selectively shunted such that beam deflection may be linearly controlled. A bidirectional switch preferably comprising a field effect transistor (FET) is connected in parallel with the capacitor which in turn is connected in series with the deflection coil of the CRT with the series combination being driven by an amplifier in response to beam positioning signals. When the bidirectional switch is activated to shunt the capacitor, the deflection control circuit operates in a linear mode; and when the switch is deactivated, the deflection coil of the CRT interacts with the capacitor for resonant nonlinear operation. A comparator circuit is connected to the output of the amplifier and coupled to the bidirectional switch through an optical coupler to activate and deactivate the switch in response to conditions within the deflection control circuit. Two capacitors and associated FET shunting circuits are provided for bidirectional resonant nonlinear operation, with the deflection coil being connected in series between the two capacitors.