US3322893A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Background scanning system for facsimile communication
Assignee: Xerox Corp
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Filing: 1963-12-11
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Granted: 1967-05-30
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Expires: 1983-12-11
Abstract
No abstract record available.
Inventors
- 👤 Stephen E Townsend
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 03:20
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/40; H04N1/403
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
201 words
IN A FACSIMILE COMMUNICATION SYSTEM FOR TRANSMITTING VIDEO SIGNALS REPRESENTATIVE OF THE LIGHT VALUES OF INTELLIGENCE ON A DOCUMENT, A TRANSMITTER COMPRISING: A LIGHT SOURCE IMAGE SCANNING MEANS FOR REPEATEDLY SCANNING SUCCESSIVE PARALLEL LINE PATHS ACROSS THE DOCUMENT WITH A LIGHT SPOT, PHOTOMULTIPLIER MEANS RESPONSIVE TO THE REFLECTED LIGHT FROM THE DOCUMENT FOR PRODUCING VIDEO SIGNALS IN ACCORDANCE WITH THE REFLECTED LIGHT VALUES INDICATIVE OF THE INTELLIGENCE AND THE BACKGROUND ON THE DOCUMENT DURING EACH SCAN OF SAID SCANNING MEANS, BACKGROUND READER CIRCUIT MEANS COUPLED TO SAID PHOTOMULTIPLIER MEANS FOR ESTABLISHING A BACKGROUND LEVEL VOLTAGE IN RESPONSE TO THE VIDEO SIGNALS INDICATIVE OF THE BACKGROUND LIGHT VALUES ON THE DOCUMENT, SAID BACKGROUND READER CIRCUIT MEANS COMPRISING FIRST STORAGE MEANS FOR STORING SAID BACKGROUND LEVEL VOLTAGE FOR A PREDETERMINED TIME, SECOND STORAGE MEANS FOR STORING SAID BACKGROUND LEVEL VOLTAGE FOR A PERIOD LONGER THAN SAID PREDETERMINED TIME TO RETAIN SAID VOLTAGE DURING CORRESPONDINGLY LONGER SCANS OF INTELLIGENCE, AND BRIGHTNESS CONTROL CIRCUIT MEANS COUPLED TO SAID BACKGROUND READER CIRCUIT MEANS AND SAID SCANNING MEANS FOR VARYING THE BRIGHTNESS OF SAID LIGHT SPOT IN RESPONSE TO VARIATIONS IN THE BACKGROUND ON SAID DOCUMENT FROM LIGHTER TO DARKER BACKGROUNDS AND FROM DARKER TO LIGHTER BACKGROUNDS.
Claim 2
Dependent Claim
201 words
IN A FACSIMILE COMMUNICATION SYSTEM FOR TRANSMITTING VIDEO SIGNALS REPRESENTATIVE OF THE LIGHT VALUES OF INTELLIGENCE ON A DOCUMENT, A TRANSMITTER COMPRISING: A LIGHT SOURCE IMAGE SCANNING MEANS FOR REPEATEDLY SCANNING SUCCESSIVE PARALLEL LINE PATHS ACROSS THE DOCUMENT WITH A LIGHT SPOT, PHOTOMULTIPLIER MEANS RESPONSIVE TO THE REFLECTED LIGHT FROM THE DOCUMENT FOR PRODUCING VIDEO SIGNALS IN ACCORDANCE WITH THE REFLECTED LIGHT VALUES INDICATIVE OF THE INTELLIGENCE AND THE BACKGROUND ON THE DOCUMENT DURING EACH SCAN OF SAID SCANNING MEANS, BACKGROUND READER CIRCUIT MEANS COUPLED TO SAID PHOTOMULTIPLIER MEANS FOR ESTABLISHING A BACKGROUND LEVEL VOLTAGE IN RESPONSE TO THE VIDEO SIGNALS INDICATIVE OF THE BACKGROUND LIGHT VALUES ON THE DOCUMENT, SAID BACKGROUND READER CIRCUIT MEANS COMPRISING FIRST STORAGE MEANS FOR STORING SAID BACKGROUND LEVEL VOLTAGE FOR A PREDETERMINED TIME, SECOND STORAGE MEANS FOR STORING SAID BACKGROUND LEVEL VOLTAGE FOR A PERIOD LONGER THAN SAID PREDETERMINED TIME TO RETAIN SAID VOLTAGE DURING CORRESPONDINGLY LONGER SCANS OF INTELLIGENCE, AND BRIGHTNESS CONTROL CIRCUIT MEANS COUPLED TO SAID BACKGROUND READER CIRCUIT MEANS AND SAID SCANNING MEANS FOR VARYING THE BRIGHTNESS OF SAID LIGHT SPOT IN RESPONSE TO VARIATIONS IN THE BACKGROUND ON SAID DOCUMENT FROM LIGHTER TO DARKER BACKGROUNDS AND FROM DARKER TO LIGHTER BACKGROUNDS.
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) | 1970-05-29 | 1970-11-28 | 1971-05-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-05-29 | 1974-11-28 | 1975-05-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-05-29 | 1978-11-28 | 1979-05-30 | $7700.00 | Window Closed / Lapsed |