US3604936A
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US
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Optical time division switching system
Assignee: AT&T Inc
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Filing: 1968-08-20
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Granted: 1971-09-14
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Expires: 1988-08-20
Abstract
Abstract An optical time division switching system is described in which coherent light from a laser is successively applied to a group of modulators controlled by electrical signals from corresponding stations. The light from each modulator is selectively delayed for transmission to another station in the group and then sequentially combined into a single light beam. This light beam is applied to a group of detectors wherein the light is successively demodulated in accordance with the selectively delay sequence. The electrical signals from each detector are connected to their corresponding stations to complete the desired communication paths.
Inventors
- 👤 Rudolf Kompfner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 04:08
CPC Classifications
H; H04; H04Q; H04Q3/00; H04Q3/42; H04Q3/52; H04Q3/526; H04J; H04J14/00; H04J14/08
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
168 words
An optical time division switching system comprising a plurality of stations, a distinct modulator and a distinct detector connected to each of said stations, a source of coherent light, means for defining repetitive time intervals, first lightdirecting means for directing light from said source to each of said modulators in succession during a distinct one of said time intervals, means for applying input signals to each of said modulators from the station connected thereto to modulate the light received from said source, means for gating light from said modulators to form light pulses in a selected sequence, means for combining the outputs of said gating means into a single light beam retaining said selected sequence, second light-detecting means for directing light pulses from said beam to each of said detectors in succession, and means for enabling said detectors to apply signals corresponding to said input signals to their connected stations comprising means for demodulating the light received in each of said detectors during said one distinct time interval.
Claim 2
Dependent Claim
168 words
An optical time division switching system comprising a plurality of stations, a distinct modulator and a distinct detector connected to each of said stations, a source of coherent light, means for defining repetitive time intervals, first lightdirecting means for directing light from said source to each of said modulators in succession during a distinct one of said time intervals, means for applying input signals to each of said modulators from the station connected thereto to modulate the light received from said source, means for gating light from said modulators to form light pulses in a selected sequence, means for combining the outputs of said gating means into a single light beam retaining said selected sequence, second light-detecting means for directing light pulses from said beam to each of said detectors in succession, and means for enabling said detectors to apply signals corresponding to said input signals to their connected stations comprising means for demodulating the light received in each of said detectors during said one distinct time interval.
Claim 3
Dependent Claim
81 words
An optical time division switching system according to claim 1 wherein said means for defining repetitive time intervals further comprises means for defining a succession of time slots in each of said intervals, each of said time slots being associated with the operation of one of said modulators, and said light-gating means comprises variable delay elements for delaying the light from said modulators for a selected number of said time slots whereby said stations are selectively interconnected for signal transfer therebetween.
Claim 4
Dependent Claim
27 words
An optical time division switching system according to claim 2 wherein each of sAid variable delay elements comprises a cascaded arrangement of selectable length light delay paths.
Claim 5
Dependent Claim
84 words
An optical time division switching system according to claim 2 wherein said coherent light source comprises a first continuous wave laser for emitting a coherent light beam, said time interval defining means comprises means for angularly rotating said coherent light beam along a conical path, said modulators being located along the circumference of a circular path, and said first light-directing means comprises means for deflecting said coherent light beam from said conical path to impinge on said modulators in said succession of time slots.
Claim 6
Dependent Claim
59 words
An optical time division switching system according to claim 4 wherein said combining means comprises conical reflecting means and means for deflecting said light pulses from said variable delay means onto said conical reflecting means at a constant angle, said conical reflecting means being operative to form a single light beam comprising said light pulses in said selected sequence.
Claim 7
Dependent Claim
62 words
An optical time division switching system according to claim 4 further comprising means for converting said light pulses from said single light beam into electrical signals, a second continuous wave laser, and means inserted between said second continuous wave laser and said second light directing means responsive to said electrical signals for modulating the coherent light from said second continuous wave laser.
Claim 8
Dependent Claim
65 words
An optical time division switching system according to claim 4 wherein said second light-directing means comprises means for angularly rotating said single light beam along a conical path in synchronism with said coherent light angularly rotating means whereby the modulated light pulses in the time slots corresponding to each one of said stations are applied to the detector connected to said one of said stations.
Claim 9
Dependent Claim
51 words
An optical time division switching system according to claim 7 wherein said time interval defining means comprises means for generating a pair of orthogonally related single frequency signals and means for applying said signal pair to said single light beam angularly rotating means and to said coherent light angularly rotating means.
Claim 10
Dependent Claim
161 words
An optical time division switching system comprising a plurality of stations, a distinct modulator and a distinct detector connected to each of said stations, means for generating a sequence of coherent light pulses defining repetitive time intervals, first means for directing each of said light pulses to said modulators in a succession of time slots during a distinct one of said time intervals, means for applying signals to each of said modulators from the station connected thereto to modulate said light pulses, means for gating light from said modulators in a selected sequence, means for combining the outputs of said gating means into a single light pulse beam retaining said selected sequence, second means for directing light pulses from said beam simultaneously to each of said detectors, and means for enabling said detectors in said succession of time slots to apply signals corresponding to said input signals to their connected stations whereby said stations are selectively interconnected for signal transfer therebetween.
Claim 11
Dependent Claim
161 words
An optical time division switching system comprising a plurality of stations, a distinct modulator and a distinct detector connected to each of said stations, means for generating a sequence of coherent light pulses defining repetitive time intervals, first means for directing each of said light pulses to said modulators in a succession of time slots during a distinct one of said time intervals, means for applying signals to each of said modulators from the station connected thereto to modulate said light pulses, means for gating light from said modulators in a selected sequence, means for combining the outputs of said gating means into a single light pulse beam retaining said selected sequence, second means for directing light pulses from said beam simultaneously to each of said detectors, and means for enabling said detectors in said succession of time slots to apply signals corresponding to said input signals to their connected stations whereby said stations are selectively interconnected for signal transfer therebetween.
Claim 12
Dependent Claim
62 words
An optical time division switching system according to claim 9 wherein said first light-pulse-directing means comprises a plurality of means each for directing a portion of said light pulse along a path of predetermined length to each modulator, said paths between said generating means and successive modulators being separated by a distance corresponding to the duration of one of said time slots.
Claim 13
Dependent Claim
42 words
An optical time division switching system according to claim 10 wherein said combining means comprises means for directing each gating means output to a common transmission path over paths of equal length between each gating means output and said common transmission path.
Claim 14
Dependent Claim
44 words
An optical time division system according to claim 11 wherein said seconD light-pulse-directing means comprises a plurality of means connected between said common transmission path and said detectors each for directing said light pulse beam along equal length paths to one of said detectors.
Claim 15
Dependent Claim
50 words
An optical time division switching system according to claim 9 wherein said detector enabling means comprises means for sequentially directing a portion of said coherent light pulses from said generating means to said detectors in said succession of time slots synchronously with the light pulses of said first light-pulse-directing means.
References Cited (Backward Citations)
US2689949A
Cited
US3363103A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-09-13 | 1975-03-15 | 1975-09-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-09-13 | 1979-03-15 | 1979-09-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-09-13 | 1983-03-15 | 1983-09-14 | $7700.00 | Window Closed / Lapsed |