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Patent US3725731A successfully refreshed from Google Patents.
US3725731A
Expired / Lapsed
US
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Self-scanning plasma display device with phosphor screen
Assignee: International Business Machines Corp
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Filing: 1971-06-29
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Granted: 1973-04-03
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Expires: 1991-06-29
Abstract
Abstract A display device having an inert gas-filled, transparent envelope, containing a set of parallel cathode elements an anode grid structure forming a venetian blind type structure and a glass support plate carrying a set of parallel conducting strips perpendicular to the plane of the parallel cathode strips and coated with a layer of ZnO phosphor. Light is emitted by the phosphor when one of the cathode elements is connected to a negative potential, the anode grid structure connected to a ground potential and one of the phosphor bearing conducting strips is connected to a low positive signal voltage. Color displays may be generated by applying a series of phosphors which generate different colors in an alternating fashion on the glass support plate.
Inventors
- 👤 B Kazan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 11:10
CPC Classifications
H; H01; H01J; H01J17/00; H01J17/38; H01J17/48; H01J17/49; H01J17/498
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
187 words
A display device for displaying alphanumeric information comprising: a gas filled transparent envelope; transparent carrier having a plurality of linear conductors mounted on one face of said carrier, said conductors carrying a signal voltage to a row of elements to be displayed, and a layer of phosphor deposited over the carrier and conductors a plurality of anode elements contained in said transparent envelope and adjacent to and space from the layer of phosphor each of said anode elements being connected to a fixed potential, said anode elements accelerating electrons to said phosphor layer; a plurality of cathode elements adjacent to and space from the anode, contained in said transparent envelope, each of said cathode elements perpendicular to said linear conductors and connected to one of a plurality of control devices, said control devices controlling the potentials applied to groups of said cathode elements, wherein on a coincidence of an activating potential applied to a cathode element, and a signal voltage applied to one of said conductors, electrons emitted by said cathode element and accelerated by said anode elements, strike said phosphor layer causing light to be emitted.
Claim 2
Dependent Claim
31 words
A display device as in claim 2 wherein said anode elements are placed at an oblique angle to the direction of electron flow to reduce ion bombardment of said phosphor layer.
Claim 3
Dependent Claim
13 words
A display device according to claim 3 wherein said phosphor layer is ZnO.
Claim 4
Dependent Claim
15 words
A display device according to claim 3 wherein said phosphor layer is a conducting material.
Claim 5
Dependent Claim
14 words
A display device according to claim 1 wherein said gas is an inert gas.
Claim 6
Dependent Claim
41 words
A display device according to claim 1 wherein said phosphor layer comprises a plurality of sets of strips of phosphor wherein each of said sets of strips of phosphor emits light of a different color to produce a colored information display.
Claim 7
Dependent Claim
21 words
A display device according to claim 1 wherein said signal voltage is varied to display information in a gray scale rendition.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-04-02 | 1976-10-02 | 1977-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-02 | 1980-10-02 | 1981-04-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-02 | 1984-10-02 | 1985-04-03 | $7700.00 | Window Closed / Lapsed |