Electric lamp and discharge devices: systems – Cathode ray tube circuits – Cathode-ray deflections circuits
Patent
1990-09-06
1991-10-08
Blum, Theodore M.
Electric lamp and discharge devices: systems
Cathode ray tube circuits
Cathode-ray deflections circuits
315382, H01J 2970, H01J 2976
Patent
active
050557491
ABSTRACT:
Apparatus in a three-beam inline electron gun system for a color cathode ray tube, wherein the tube has a screen and a partially self-converging yoke which partially, but incompletely, converges the three beams and undesirably imparts astigmatism to the beams in off-center regions of the screen, applies a field-strength-dependent asymmetrical field to the two outer beams to provide partial dynamic convergence. The apparatus includes an electron beam source for developing three electron beams, a focusing lens portion for focusing the three electron beams at the tube screen, an astigmatism correcting lens portion for developing an astigmatic field component in the path of each of the beams, and a modulated voltage source for modulating the strength of the astigmatic field component as a function of beam deflection angle to at least partially compensate for the yoke-induced astigmatism and for modulating focus field strength in providing partial dynamic electron beam convergence. The astigmatism correcting lens portion includes an electrode having outer beam apertures shaped to create field-strength-dependent asymmetric outer beam fields and to produce partial dynamic convergence, with the dynamic convergence effects of the yoke, the focusing lens portion, and the astigmatism correcting lens portion combining additively.
REFERENCES:
patent: 3772554 (1973-11-01), Hughes
patent: 4058753 (1977-11-01), Blacker et al.
patent: 4701677 (1987-10-01), Ashizaki et al.
patent: 4771216 (1988-09-01), Blacker et al.
patent: 4814670 (1989-03-01), Suzuki et al.
patent: 4886999 (1989-12-01), Yamane et al.
Chen Hsing-Yao
Gorski Richard M.
Blum Theodore M.
Zenith Electronics Corporation
LandOfFree
Self-convergent electron gun system does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Self-convergent electron gun system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Self-convergent electron gun system will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-259095