Title :
Interdigital grids for dynamic astigmatism control in picture-tube guns
Author :
Bloom, Stanley ; Hockings, Eric F.
Author_Institution :
RCA Corp., Princeton, NJ, USA
fDate :
4/1/1989 12:00:00 AM
Abstract :
Astigmatism control of Coty-29 picture tubes has been achieved through the incorporation of interdigital grids in the gun-focus electrode. These grids produce quadrupolar fields so that the focusing induced in the beam´s vertical ray by the self-convergent yoke is compensated, thus eliminating the vertical flare previously observed for deflecting spots. The utility of cross plots for studying astigmatic gun/yoke systems and for measuring gun and yoke astigmatism values has been demonstrated. Measurements on a number of tubes are described and the results are compared with formulas derived from paraxial equations
Keywords :
colour television picture tubes; electron guns; electron lenses; focusing; Coty-29; astigmatic gun/yoke systems; deflecting spots; dynamic astigmatism control; focusing compensation; gun-focus electrode; inline colour picture tubes; interdigital grids; picture-tube guns; quadrupolar fields; quadrupole lens; self-convergent yoke; vertical flare elimination; Apertures; Electrodes; Equations; Guns; Helium; Lenses; Magnetic field measurement; Optical modulation; Shape; Vision defects;
Journal_Title :
Electron Devices, IEEE Transactions on
