US2740901A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Differential photocell detector using junction semiconductors
Assignee: AT&T Inc
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Filing: 1951-12-29
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Granted: 1956-04-03
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Expires: 1971-12-29
Abstract
No abstract record available.
Inventors
- 👤 Robert E Graham
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 05:39
CPC Classifications
G; G01; G01J; G01J1/00; G01J1/10; G01J1/16; G01J1/1626; H; H10; H10F; H10F99/00; H10F30/00; H10F30/20
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
101 words
A PHOTOELECTRIC DEVICE COMPRISING A BODY OF SEMICONDUCTIVE MATERIAL HAVING THEREIN A NARROW ZONE OF ONE CONDUCTIVITY TYPE BETWEEN AND CONTIGUOUS WITH A PAIR OF OUTER ZONES OF THE OPPOSITE CONDUCTIVITY TYPE, TERMINAL CONNECTIONS TO SAID OUTER ZONES, AND ILLUMINATION MEANS FOR SAID SEMICONDUCTOR BODY CONSISTING OF MEANS FOR DIRECTING AGAINST SAID BODY A SINGLE LIGHT BEAM WHICH HAS A LIGHT DISTRIBUTION CHARACTERISTIC AT THE BODY SURFACE WHICH SUBSTANTIALLY MATCHES IN SHAPE THE INTEGRAL OF THE SENSITIVITY CHARACTERISTIC G(X) OF SAID MATERIAL, WHERE G(X) IS A PLOT OF VOLTAGE VS. LIGHT POSITION OF THE SPOT WITH RESPECT TO SAID FIRST-MENTIONED ZONE.
Claim 2
Dependent Claim
101 words
A PHOTOELECTRIC DEVICE COMPRISING A BODY OF SEMICONDUCTIVE MATERIAL HAVING THEREIN A NARROW ZONE OF ONE CONDUCTIVITY TYPE BETWEEN AND CONTIGUOUS WITH A PAIR OF OUTER ZONES OF THE OPPOSITE CONDUCTIVITY TYPE, TERMINAL CONNECTIONS TO SAID OUTER ZONES, AND ILLUMINATION MEANS FOR SAID SEMICONDUCTOR BODY CONSISTING OF MEANS FOR DIRECTING AGAINST SAID BODY A SINGLE LIGHT BEAM WHICH HAS A LIGHT DISTRIBUTION CHARACTERISTIC AT THE BODY SURFACE WHICH SUBSTANTIALLY MATCHES IN SHAPE THE INTEGRAL OF THE SENSITIVITY CHARACTERISTIC G(X) OF SAID MATERIAL, WHERE G(X) IS A PLOT OF VOLTAGE VS. LIGHT POSITION OF THE SPOT WITH RESPECT TO SAID FIRST-MENTIONED ZONE.
References Cited (Backward Citations)
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US2482980A
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US2570978A
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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) | 1959-04-03 | 1959-10-03 | 1960-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-04-03 | 1963-10-03 | 1964-04-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-04-03 | 1967-10-03 | 1968-04-03 | $7700.00 | Window Closed / Lapsed |