Patent US3724926A successfully refreshed from Google Patents.
US3724926A
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Optical pulse modulator
Assignee: AT&T Inc
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Filing: 1971-08-09
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Granted: 1973-04-03
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Expires: 1991-08-09
Abstract
Abstract A high speed optical modulator, in accordance with the present disclosure, comprises a pair of p-n junction diodes, one of which is an amplifier, and the other of which is a saturable absorber. A constant current initially forward-biases the amplifier to approximately unity gain. A pulse-encoded information signal is superimpressed upon this constant bias such that incident optical pulses are transmitted at unity gain for one binary state of the information signal and at a greater gain for the other binary state. The power ratio of the optical pulses for the two binary states is then increased by the saturable absorber which attenuates the smaller optical signal to a much greater extent than it attenuates the larger signal.
Inventors
- 👤 T Lee
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 10:41
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/015; G02F1/025; H; H01; H01S; H01S5/00; H01S5/50; G02F1/0155; G02F2203/00; G02F2203/26; H01S5/02; H01S5/026; H01S5/0265
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
101 words
An optical wave modulator comprising: a binary-encoded information signal source; a variable gain optical wave amplifier for amplifying externally applied optical wave energy; means for coupling said signal source to said amplifier for increasing the gain of said amplifier for one binary state of said information signal while maintaining a lower amplifier gain for the other binary state of said information signal; and a saturable absorber positioned to receive optical wave energy from said amplifier and to attenuate optical wave energy corresponding to said other binary state to a greater degree than optical wave energy corresponding to said one binary state.
Claim 2
Dependent Claim
101 words
An optical wave modulator comprising: a binary-encoded information signal source; a variable gain optical wave amplifier for amplifying externally applied optical wave energy; means for coupling said signal source to said amplifier for increasing the gain of said amplifier for one binary state of said information signal while maintaining a lower amplifier gain for the other binary state of said information signal; and a saturable absorber positioned to receive optical wave energy from said amplifier and to attenuate optical wave energy corresponding to said other binary state to a greater degree than optical wave energy corresponding to said one binary state.
Claim 3
Dependent Claim
14 words
The modulator according to claim 1 wherein said amplifier is a p-n junction diode.
Claim 4
Dependent Claim
15 words
The modulator according to claim 1 wherein said saturable absorber is a p-n junction diode.
Claim 5
Dependent Claim
23 words
The modulator accordinG to claim 1 wherein both said amplifier and said saturable absorber comprise a monolithic structure including two p-n junction diodes.
Claim 6
Dependent Claim
143 words
The combination comprising, in cascade: a source of optical pulses and an optical wave modulator; said modulator including: a p-n junction diode optical wave amplifier having its junction aligned with the direction of propagation of optical pulses derived from said source; means for biasing said diode to transmit said optical pulses at approximately unity gain; means, comprising a binary-encoded information signal source synchronized with said optical pulses, for modulating the bias applied to said diode so as to increase the gain of said amplifier for one binary state of said information signal while maintaining unity gain for the other binary state of said information signal; and a saturable absorber positioned to receive optical pulses from said amplifier and to attenuate optical wave energy corresponding to said other binary state to a greater degree than optical wave energy corresponding to said one binary state.
Claim 7
Dependent Claim
143 words
The combination comprising, in cascade: a source of optical pulses and an optical wave modulator; said modulator including: a p-n junction diode optical wave amplifier having its junction aligned with the direction of propagation of optical pulses derived from said source; means for biasing said diode to transmit said optical pulses at approximately unity gain; means, comprising a binary-encoded information signal source synchronized with said optical pulses, for modulating the bias applied to said diode so as to increase the gain of said amplifier for one binary state of said information signal while maintaining unity gain for the other binary state of said information signal; and a saturable absorber positioned to receive optical pulses from said amplifier and to attenuate optical wave energy corresponding to said other binary state to a greater degree than optical wave energy corresponding to said one binary state.
Claim 8
Dependent Claim
15 words
The combination according to claim 5 wherein said saturable absorber is a p-n junction diode.
Claim 9
Dependent Claim
24 words
The modulator in accordance with claim 6, including means for modulating the bias applied to said saturable absorber in accordance with said information signal.
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 |