Electron gun for color picture tube

Abstract

Abstract PURPOSE:To obtain excellent focusing characteristic and resolution over an entire picture surface by providing on each side of a 1st and 2nd focusing electrodes facing each other with two circular electron beam passing holes having arc-shaped projecting burrings and by applying a dynamic voltage for offsetting the distortion of an electron beam to the 2nd focusing electrode. CONSTITUTION:An electron beam emitted from a cathode passes a control electrode 22, an acceleration electrode 23, a 1st focusing electrode 24, a 2nd focusing electrode 25, and a final acceleration electrode 26, and reaches a display surface. Arc-shaped burrings 31 projecting on right and left are provided on the 2nd focusing electrode 25 side of the 1st focusing electrode 24 while arc-shaped burrings 32 projecting at upper and lower positions are provided on the 1st focusing electrode 24 side of the 2nd focusing electrode 25. When a voltage higher than that applied to the 1st focusing electrode 24 is applied to the 2nd focusing electrode 25, the electron beam 27 receives a divergent force in the vertical direction and a convergent force in the horizontal direction. It is possible to eliminate the attenuation of the electron beam even on the peripheral portions of the screen by applying a voltage that offsets an optimum focus potential difference between vertical and horizontal directions on the peripheral portions of the screen.

Inventors

• 👤 Akira Shishido

Bibliographic Details