The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 04, 1996
Filed:
Mar. 11, 1993
Wan-Jae Son, Kyungki-do, KR;
Yu-Seon Kim, Kyungki-do, KR;
Samsung Electron Devices, Kyungki-do, KR;
Abstract
An electron gun for a color cathode ray tube includes a triode having a cathode, a control electrode and a screen electrode for producing an electron beam, and first, second, third and fourth focus electrodes and a final accelerating electrode for accelerating and focusing the electron beam. A predetermined static focus voltage is supplied to the first and third focus electrodes, a dynamic focus voltage synchronized with a deflection signal is supplied to the second and fourth focus electrodes, and an anode voltage higher than the highest dynamic focus voltage is supplied to the final accelerating electrode. Thus, by means of a dynamic and axially symmetrical lens, astigmatism of the electron beam spot on the periphery of the screen is improved, thereby forming an almost circular beam spot. Due to the dynamic variation of intensity of the main lens, the spot size on the periphery of the screen approaches is the spot size on the center of the screen through adjustment of the focusing distance of the electron beam.