Electric lamp and discharge devices: systems – Cathode ray tube circuits – Cathode-ray deflections circuits
Patent
1992-12-11
1994-11-29
Issing, Gregory C.
Electric lamp and discharge devices: systems
Cathode ray tube circuits
Cathode-ray deflections circuits
315403, 327134, 327139, G09G 104, H01J 2970, H03K 408
Patent
active
053693418
ABSTRACT:
A television receiver is controlled as to the degree of vertical zoom via a deflection current ramp that varies in slope and which may be delayed to achieve panning. Due to the increased slope when zoomed, the deflection current and the electron beam complete a trace in less time than the normal vertical interval. The deflection current is maintained at one extreme or the other outside the trace interval, and the beam is blanked. A retrace signal generator coupled in a feedback loop with the power supply for the deflection circuit determines the midpoint of the blanking period and generates a fast retrace at or near the midpoint. The feedback loop is arranged to minimize the DC average current in the deflection winding by having a current source responsive to the DC average current for charging a timing ramp that triggers retrace upon reaching a threshold. The slope of the timing ramp varies with DC loading, thus advancing or retarding retrace to center retrace in the blanking interval.
REFERENCES:
patent: 3471743 (1969-10-01), Olsson et al.
patent: 3705328 (1972-12-01), Torok
patent: 3713000 (1973-01-01), Driskell et al.
patent: 4028726 (1977-06-01), Argy
patent: 4820960 (1989-04-01), Fazio
patent: 4874992 (1989-10-01), Benson
U.S. Patent Application titled Reduced Dissipation Vertical Deflection Circuit for Zoom Mode Operation by J. Wilber, Ser. No. 911,605, filed Jul. 10, 1992.
Issing Gregory C.
Laks Joseph J.
Sragow Daniel E.
Thomson Consumer Electronics Inc.
Tripoli Joseph S.
LandOfFree
Vertical retrace with zoom and centered fast retrace does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Vertical retrace with zoom and centered fast retrace, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Vertical retrace with zoom and centered fast retrace will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-75902