US3970889A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Erasure means for charge storage device
Assignee: Tektronix Inc
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Filing: 1973-11-21
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Granted: 1976-07-20
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Expires: 1993-11-21
Abstract
Abstract In a charge storage device, such as a high resolution scan converter tube, flood guns are incorporated to scan the target with substantially unfocused high current electron beams to provide the erasure thereof.
Inventors
- 👤 G. Harold Cobb
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 14:42
CPC Classifications
H; H01; H01J; H01J31/00; H01J31/08; H01J31/58; H01J31/60
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
96 words
A charge storage scan conversion apparatus, comprising: an evacuated envelope having a longitudinal axis; storage target means mounted within said envelope, said target means including a storage element of dielectric material provided on a target electrode; write-read means for producing a low-current first electron beam of narrow divergence angle, said write-read means including first electron gun means; erase means for producing a high-current second electron beam, said erase means including second electron gun means; and scanning means for deflecting said first and second electron beams across the surface of said storage target in a predetermined manner.
Claim 2
Dependent Claim
96 words
A charge storage scan conversion apparatus, comprising: an evacuated envelope having a longitudinal axis; storage target means mounted within said envelope, said target means including a storage element of dielectric material provided on a target electrode; write-read means for producing a low-current first electron beam of narrow divergence angle, said write-read means including first electron gun means; erase means for producing a high-current second electron beam, said erase means including second electron gun means; and scanning means for deflecting said first and second electron beams across the surface of said storage target in a predetermined manner.
Claim 3
Dependent Claim
43 words
The apparatus according to claim 1 wherein said first electron gun means is positioned on the centerline of said longitudinal axis, said second electron gun means is positioned parallel to said centerline, and said target means is positioned transversely to said longitudinal axis.
Claim 4
Dependent Claim
16 words
The apparatus according to claim 1 wherein said second electron gun means comprises flood gun means.
Claim 5
Dependent Claim
30 words
The apparatus according to claim 1 including first focusing means for shaping said first electron beam only, and second focusing means for shaping both said first and second electron beams.
Claim 6
Dependent Claim
14 words
The apparatus according to claim 1 wherein said scanning means is a deflectron structure.
Claim 7
Dependent Claim
73 words
An improved charge storage device comprisng: an evacuated envelope; storage target means mounted within said envelope for storing images thereon; means for producing a low-current electron beam of narrow divergence angle for reading said images stored on said target means; means for deflecting said low-current electron beam across the surface of said target means in a predetermined manner; and means for producing at least one high-current electron beam for erasing said target means.
Claim 8
Dependent Claim
73 words
An improved charge storage device comprisng: an evacuated envelope; storage target means mounted within said envelope for storing images thereon; means for producing a low-current electron beam of narrow divergence angle for reading said images stored on said target means; means for deflecting said low-current electron beam across the surface of said target means in a predetermined manner; and means for producing at least one high-current electron beam for erasing said target means.
Claim 9
Dependent Claim
60 words
The device according to claim 6 wherein said means for producing a low-current electron beam of narrow divergence angle is an electron gun having a beam-limiting aperture for passage therethrough of said beam; said means for deflecting said beam is a deflection electrode structure having scanning signals applied thereto; and said means for producing high-current electron beams are flood guns.
Claim 10
Dependent Claim
23 words
The device according to claim 6 wherein said means for deflecting said low-current electron beam is also for scanning said high-current electron beam.
Claim 11
Dependent Claim
43 words
The device according to claim 6 wherein said storage target means includes a conductive backplate member having dielectric material provided thereon, and said means for producing a low-current electron beam of narrow divergence angle is also for writing images upon said target means.
Claim 12
Dependent Claim
54 words
The device according to claim 9 wherein said backplate member has a high voltage level applied thereto for the writing operation of said target means, a low voltage level applied thereto for the reading operation of said target means, and an intermediate voltage level applied thereto for the erasing operation of said target means.
Claim 13
Dependent Claim
16 words
The device according to claim 6 wherein said means for deflecting said beam is a deflectron.
Claim 14
Dependent Claim
28 words
The device according to claim 6 including first focusing means for focusing said low-current beam only, and second focusing means for focusing both said low-current and high-current beams.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-07-20 | 1980-01-19 | 1980-07-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-07-20 | 1984-01-19 | 1984-07-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-07-20 | 1988-01-19 | 1988-07-20 | $7700.00 | Window Closed / Lapsed |