Patent US4481445A successfully refreshed from Google Patents.
US4481445A
Expired / Lapsed
US
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Electron gun for projection television cathode ray tubes
Assignee: Zenith Electronics LLC
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Filing: 1982-06-01
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Granted: 1984-11-06
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Expires: 2002-06-01
Abstract
Abstract A high-performance bipotential-type electron gun comprises a series of electrodes aligned in spaced relation on an axis. The gun has in the order named lower end means including a cathode, and an apertured plate control electrode and grid electrode. An entry angle control electrode is located between the lower end electrodes and the main focus lens. The main focus lens includes a focusing electrode and a final accelerating electrode. The electron gun according to the invention is defined in terms of dimensions, electrical potentials and ratios thereof which are effective to provide an electron gun of particular suitability for use in projection cathode ray tubes.
Inventors
- 👤 Richard M. Gorski
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 14:06
CPC Classifications
H; H01; H01J; H01J29/00; H01J29/46; H01J29/48; H01J29/488
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
147 words
A high-performance bipotential-type electron gun comprising a series of electrodes aligned in spaced relation on an axis, having in the order named, lower end means including a cathode (K), and an apertured plate control electrode (G1), a grid electrode (G2), an entry angle control electrode (G2'); and a cylindrical electrode focus lens means including a focusing electrode (G3), and a final accelerating electrode (G4), said electron gun having the following approximate dimensions and spacings: ______________________________________
K-G1 spacing (cold)
0.007
G1 aperture diameter
0.025
G1 thickness, at aperture
0.007
G2 aperture diameter
0.036
G2 thickness, at aperture
0.006
G1-G2 spacing 0.007
G2' aperture diameter
0.054
G2' thickness at aperture
0.012
G2-G2' spacing 0.030
G2'-G3 spacing 0.030
G3 aperture diameter
0.065
G3 thickness at aperture
0.010
G3 axial length 1.75
G3 lens diameter 0.437
G3-G4 spacing 0.060
G4 axial length 0.70
G4 lens diameter 0.437
Gun length 2.60
______________________________________
Claim 2
Dependent Claim
147 words
A high-performance bipotential-type electron gun comprising a series of electrodes aligned in spaced relation on an axis, having in the order named, lower end means including a cathode (K), and an apertured plate control electrode (G1), a grid electrode (G2), an entry angle control electrode (G2'); and a cylindrical electrode focus lens means including a focusing electrode (G3), and a final accelerating electrode (G4), said electron gun having the following approximate dimensions and spacings: ______________________________________
K-G1 spacing (cold)
0.007
G1 aperture diameter
0.025
G1 thickness, at aperture
0.007
G2 aperture diameter
0.036
G2 thickness, at aperture
0.006
G1-G2 spacing 0.007
G2' aperture diameter
0.054
G2' thickness at aperture
0.012
G2-G2' spacing 0.030
G2'-G3 spacing 0.030
G3 aperture diameter
0.065
G3 thickness at aperture
0.010
G3 axial length 1.75
G3 lens diameter 0.437
G3-G4 spacing 0.060
G4 axial length 0.70
G4 lens diameter 0.437
Gun length 2.60
______________________________________
Claim 3
Dependent Claim
58 words
The electron gun of claim 1 for operation with the following approximate ranges of electrical potentials, as expressed in volts: ______________________________________
K potential (at cut-off)
125 to 220
G1 potential 0
G2 potential (with K between 125-220
1,200 to 2,200
volt cut-off)
G2' potential -500 to +500
G3 potential 4,700 to 7,600
G4 potential 20,000 to 32,000
______________________________________
Claim 4
Dependent Claim
46 words
The electron gun according to claim 1 for operation with the following approximate electrical potentials, as expressed in volts: ______________________________________
K potential (at cut-off) 190
G1 potential 0
G2 potential, at 190 volt K cut-off
1,900
G2' potential 220
G3 potential 7,110
G4 potential 30,000
______________________________________
Claim 5
Dependent Claim
111 words
A high performance electron gun comprising a series of apertured electrodes aligned in spaced relation on an axis including an entry angle control electrode (G2') and cylindrical main focus lens electrodes in the order named, a focus electrode (G3), and an accelerating electrode (G4), said gun being characterized by having the following approximate ratios: a G3 lens diameter to G3 length ratio of about 0.25; a G3 electrode potential to G4 electrode potential ratio of about 0.24; a gun length to throw distance ratio of about 0.53; a G3 electrode length to gun length ratio of about 0.68; and a G2' electrode potential to G2 electrode potential ratio of about 0.12.
Claim 6
Dependent Claim
111 words
A high performance electron gun comprising a series of apertured electrodes aligned in spaced relation on an axis including an entry angle control electrode (G2') and cylindrical main focus lens electrodes in the order named, a focus electrode (G3), and an accelerating electrode (G4), said gun being characterized by having the following approximate ratios: a G3 lens diameter to G3 length ratio of about 0.25; a G3 electrode potential to G4 electrode potential ratio of about 0.24; a gun length to throw distance ratio of about 0.53; a G3 electrode length to gun length ratio of about 0.68; and a G2' electrode potential to G2 electrode potential ratio of about 0.12.
References Cited (Backward Citations)
US4334170A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1987-11-06 | 1988-05-07 | 1988-11-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-11-06 | 1992-05-07 | 1992-11-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-11-06 | 1996-05-07 | 1996-11-06 | $7700.00 | Window Closed / Lapsed |