EP 0275191 A2 19880720 - Color cathode-ray tube having a three-lens electron gun.
Title (en)
Color cathode-ray tube having a three-lens electron gun.
Title (de)
Farbbildröhre mit einer Drei-Linsen-Elektronenkanone.
Title (fr)
Tube image couleur muni d'un canon à trois lentilles.
Publication
Application
Priority
- GB 8700792 A 19870114
- GB 8700793 A 19870114
- US 12895187 A 19871204
Abstract (en)
An improved color cathode-ray tube includes an electron gun for generating and directing three inline beams, a center beam and two side beams, along initially coplanar paths toward a screen of the tube. The gun includes, in order from its cathode end (K), a plurality of spaced electrodes (G1-G6) which provide a first (L1), a second (L2) and a third (L3) lens for focusing the electron beams. The first lens has a beam forming region for providing substantially symmetrical beams to the second lens. The improvement is in the combination of the second and third lens. The second lens includes at least one electrode (G4) to provide asymmetrically-shaped beams. The potentials applied to the second lens refract electron beams emerging off-axes from the first lens toward the axes. The third lens is a low aberration main focusing lens which provides asymmetrically-shaped beams of substantially constant current density to the screen.
IPC 1-7
IPC 8 full level
H01J 29/48 (2006.01); H01J 29/50 (2006.01)
CPC (source: EP)
H01J 29/503 (2013.01); H01J 2229/4872 (2013.01); H01J 2229/4896 (2013.01)
Designated contracting state (EPC)
DE FR GB IT
DOCDB simple family (publication)
EP 0275191 A2 19880720; EP 0275191 A3 19890607; EP 0275191 B1 19950927; DE 3854506 D1 19951102; DE 3854506 T2 19960404; JP H0748354 B2 19950524; JP S63198241 A 19880816
DOCDB simple family (application)
EP 88300247 A 19880113; DE 3854506 T 19880113; JP 669688 A 19880113