| 摘要 |
PURPOSE:To enable inter-electrode voltage withstand processing without damaging the cathode face by switching G4 electrode at main electron lens section from G2 electrode under manufacture to G1 electrode under usage at the outside of cathode ray tube. CONSTITUTION:The electron gun structure is constructed with beam forming section comprised of cathode 1, G1 electrode 2 and G2 electrode 3 and main lens section comprised of G3 electrode 11, G4 electrode 12, G5 electrode 13 and G6 electrode 14. Then an intermediate potential voltage of 20-40% of that to be applied onto G6 electrode 14 is applied in common onto G3 and G5 electrodes 11, 13. G4 electrode 12 is connected go G2 electrode 2 under manufacturing at the outside of tube while connected to G1 electrode 2 for providing the potential lower than the ground potential under usage. Consequently, main electron lens splitted into two stages will reduce the astigmatism while to improve the resolution and to enable voltage withstand processing without damaging the cathode resulting in improvement of the reliability. |
