Cathode ray tube with compensation for beam landing spot distortion due to wide-angle beam deflection
US3949262A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 21, 1975 |
| Grant date | Apr 6, 1976 |
| Priority date | — |
| Expiry date | May 21, 1995 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J29/62
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
In a cathode ray tube in which an electron gun directs one or more electron beams against a phosphor screen through an electron focusing lens, preferably of the unipotential type, constituted by a plurality of tubular electrodes arranged coaxially in succession along the tube axis with a relatively low potential being applied to one of the electrodes and a relatively high potential being applied to the other electrodes, and in which each electron beam is deflected, after passing through the focusing lens, so as to scan the screen in line-scanning and vertical directions; distortion of the landing spot of each beam on the screen, particularly when deflected toward the peripheral portions of the screen, is removed or compensated by forming the tubular electrode which is maintained at the relatively low potential of two axially divided tubular electrode portions having respective end plates or walls extending across their adjacent ends and formed with aligned apertures for the passage through the latter of each beam, with a first pair of diametrically opposed flanges projecting from the periphery of one of the apertures in the axial direction toward the other aperture, and a second pa…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.