Interdigital grids for dynamic astigmatism control in picture-tube guns

Author

Bloom, Stanley ; Hockings, Eric F.

Author_Institution

RCA Corp., Princeton, NJ, USA

Volume

36

Issue

4

fYear

1989

fDate

4/1/1989 12:00:00 AM

Firstpage

777

Lastpage

784

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;

fLanguage

English

Journal_Title

Electron Devices, IEEE Transactions on

Publisher

ieee

ISSN

0018-9383

Type

jour

DOI

10.1109/16.22487

Filename

22487