US4340840A
Expired / Lapsed
US
⏱️ 0.0 years remaining
DC Gas discharge display panel with internal memory
Assignee: International Business Machines Corp
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Filing: 1980-04-21
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Granted: 1982-07-20
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Expires: 2000-04-21
Abstract
Abstract A D.C. gaseous discharge display panel operated in a storage mode uses a layer of resistive material over the cathodes of the display. In addition to protecting the electrodes from ion bombardment induced sputtering during discharge, the material provides a resistance to each discharge cell, provides isolation between individual cathodes by reducing discharge spreading along the cathode conductors and prevents surface charge building during panel operation. By utilizing a combination of metal and insulator in the resistance layer, the D.C. discharge can be sustained at lower operating voltage, permitting a reduction in the power requirements of the panel.
Inventors
- 👤 Mohamed O. Aboelfotoh
- 👤 Marvin B. Skolnik
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 14:10
CPC Classifications
H; H01; H01J; H01J11/00
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
127 words
A D.C. gaseous discharge display device with internal memory comprising in combination, an ionizable gaseous medium in a gas chamber formed by a pair of glass plates, a parallel cathode conductor array disposed on one of said glass plates, a parallel anode conductor array disposed on the other of said pair of glass plates, said first and second conductor arrays being disposed substantially orthogonal to each other, the intersections of said cathode and anode conductors defining gas discharge cells, a layer of resistive material overlying one of said conductor arrays to provide a uniform and stable resistance to and to limit the current through each of said cells during discharge of said gaseous discharge display device, and a cermet layer overlying the other of said conductors arrays.
Claim 2
Dependent Claim
127 words
A D.C. gaseous discharge display device with internal memory comprising in combination, an ionizable gaseous medium in a gas chamber formed by a pair of glass plates, a parallel cathode conductor array disposed on one of said glass plates, a parallel anode conductor array disposed on the other of said pair of glass plates, said first and second conductor arrays being disposed substantially orthogonal to each other, the intersections of said cathode and anode conductors defining gas discharge cells, a layer of resistive material overlying one of said conductor arrays to provide a uniform and stable resistance to and to limit the current through each of said cells during discharge of said gaseous discharge display device, and a cermet layer overlying the other of said conductors arrays.
Claim 3
Dependent Claim
19 words
A device of the character claimed in claim 1 wherein said resistive material layer overlies said anode conductor array.
Claim 4
Dependent Claim
32 words
A device of the character claimed in claim 2 wherein said resistive material layer has sufficient conductivity to prevent the buildup of surface charge during operation of said gaseous discharge display device.
Claim 5
Dependent Claim
25 words
A device of the type claimed in claim 3 wherein said layer of resistive material consists of a mixture of a metal and an insulator.
Claim 6
Dependent Claim
20 words
A device of the type claimed in claim 4 wherein said metal is chromium, nickel, gold, silver or combinations thereof.
Claim 7
Dependent Claim
20 words
A device of the type claimed in claim 4 wherein said insulator is silicon dioxide, magnesium oxide or compounds thereof.
Claim 8
Dependent Claim
19 words
A device of the type claimed in claim 2 wherein said resistive material layer is composed of semiconductor material.
Claim 9
Dependent Claim
21 words
A device of the character claimed in claim 7 wherein said layer of semiconductor material is disposed over said anode array.
Claim 10
Dependent Claim
17 words
A device of the type claimed in claim 1 wherein said cermet layer overlies said cathode conductors.
References Cited (Backward Citations)
US3334269A
Cited
US4053804A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-07-19 | 1986-01-18 | 1986-07-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-07-19 | 1990-01-18 | 1990-07-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-07-19 | 1994-01-18 | 1994-07-20 | $7700.00 | Window Closed / Lapsed |