EP 0198753 B1 19900103 - ELECTRON GUN FOR A CATHODE RAY TUBE, IN PARTICULAR FOR COLOUR TELEVISION
Title (en)
ELECTRON GUN FOR A CATHODE RAY TUBE, IN PARTICULAR FOR COLOUR TELEVISION
Publication
Application
Priority
- FR 8504848 A 19850329
- FR 8512419 A 19850814
Abstract (en)
[origin: EP0198753A1] 1. An electron gun for a cathode ray tube, more especially for color television, whose electrostatic lenses comprise an electrode (G4 ) which remains at an elevated potential after cutoff of the supply of the tube, characterized in that in order to reduce the effect on the cathode (K) of the elevated potential remaining at the said electrode (G4 ) after the cutoff of the supply, the gun comprises means for putting the distance between the cathode and an equipotential surface constituting the limit of the zone of influence of the potential induced by the said electrode remaining at the elevated potential, at a value such that the said elevated potential remaining on the said electrode (G4 ) after cutoff of the supply has a weak effect on the cathode, said means comprising masking means forming a part of a gun electrode with an intermediate position between the electrode (G4 ) at the elevated potential and the cathode, and in that the intermediate electrode (G3 ) held at ground potential has an elongated form along the axis (11) of the gun with two end walls (15, 16 and 18), the end wall facing the cathode having, in order to perform said masking, a greater thickness than the opposite wall (15).
IPC 1-7
IPC 8 full level
H01J 29/48 (2006.01); H01J 29/50 (2006.01)
CPC (source: EP)
H01J 29/488 (2013.01); H01J 29/503 (2013.01); H01J 2229/4872 (2013.01)
Designated contracting state (EPC)
AT DE GB IT NL
DOCDB simple family (publication)
EP 0198753 A1 19861022; EP 0198753 B1 19900103; CA 1248576 A 19890110; DE 3668096 D1 19900208; HK 17495 A 19950217; JP 2553468 B2 19961113; JP S61227347 A 19861009; SG 135292 G 19930416
DOCDB simple family (application)
EP 86400661 A 19860327; CA 505384 A 19860327; DE 3668096 T 19860327; HK 17495 A 19950209; JP 7061186 A 19860329; SG 135292 A 19921230