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US3773289A
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Photodetector delay equalizer
Assignee: AT&T Inc
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Filing: 1972-06-20
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Granted: 1973-11-20
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Expires: 1992-06-20
Abstract
Abstract This application discloses a new photodetector with built-in delay for the equalization of the delay distortion produced in multimode optical fibers. The device combines the known advantages of photodiodes and semiconductor delay lines in a single, semiconductor platelet.
Inventors
- 👤 D Gloge
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 20:26
CPC Classifications
H; H04; H04B; H04B10/00; H04B10/25; H04B10/2507; G; G02; G02B; G02B6/00; G02B6/24; G02B6/42; G02B6/4201; G02B6/4202; G02B6/4204; G02B6/4212; H10; H10F; H10F99/00
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
102 words
A photodetector adapted to compensate for the delay distortion in a multimode optical fiber comprising: means, including a photoresponsive semiconductor material of a first conductivity type, for generating electron carrier-hole carrier pairs in response to a beam of incident radiation; a collecting region of opposite conductivity type disposed along a portion of said material; and separate means for causing one of the two types of said generated carriers to drift towards said collecting region wherein the drift time for said one type carrier generated by the faster propagating modes travel a greater distance than the carriers generated by the slower propagating modes.
Claim 2
Dependent Claim
102 words
A photodetector adapted to compensate for the delay distortion in a multimode optical fiber comprising: means, including a photoresponsive semiconductor material of a first conductivity type, for generating electron carrier-hole carrier pairs in response to a beam of incident radiation; a collecting region of opposite conductivity type disposed along a portion of said material; and separate means for causing one of the two types of said generated carriers to drift towards said collecting region wherein the drift time for said one type carrier generated by the faster propagating modes travel a greater distance than the carriers generated by the slower propagating modes.
Claim 3
Dependent Claim
19 words
The photodetector according to claim 1 wherein said semiconductor material is n-type material; and wherein said carriers are hole-carriers.
Claim 4
Dependent Claim
29 words
The photodetector according to claim 1 wherein said means for causing the carriers of said one type to drift produces an electric field whose intensity varies inversely with distance.
Claim 5
Dependent Claim
49 words
A detector-equalizer comprising: a platelet of an n-type photoresponsive semiconductor material including: a region of n -type conductivity defining the center of said detector-equalizer; a first circular region of p-type conductivity concentric with said center; and a second, larger circular region of n -type conductivity concentric with said center.
Claim 6
Dependent Claim
49 words
A detector-equalizer comprising: a platelet of an n-type photoresponsive semiconductor material including: a region of n -type conductivity defining the center of said detector-equalizer; a first circular region of p-type conductivity concentric with said center; and a second, larger circular region of n -type conductivity concentric with said center.
Claim 7
Dependent Claim
28 words
The detector-equalizer according to claim 4 including: means for back-biasing said p-type region relative to said n -type regions; and an output load connected to said p-type region.
Claim 8
Dependent Claim
14 words
The detector-equalizer according to claim 4 including: a segment of optical fiber bonded thereto.
Claim 9
Dependent Claim
15 words
The photodetector according to claim 1 including an output load connected to said collecting region.
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) | 1976-11-19 | 1977-05-21 | 1977-11-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-11-19 | 1981-05-21 | 1981-11-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-11-19 | 1985-05-21 | 1985-11-20 | $7700.00 | Window Closed / Lapsed |