US3987257A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optically coupled two-wire to four-wire hybrid lines
Assignee: International Telephone and Telegraph Corp
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Filing: 1975-05-29
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Granted: 1976-10-19
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Expires: 1995-05-29
Abstract
Abstract Two-wire telephone lines connecting between subscriber telephones and the central office telephone system are coupled to four-wire transmission lines within the central office by means of phototransistors and light emitting diodes. The use of the phototransistors and light emitting diodes provides two-wire to four-wire conversion between balanced two-wire lines.
Inventors
- 👤 Harry Place
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 03:58
CPC Classifications
H; H04; H04Q; H04Q3/00; H04B; H04B1/00; H04B1/38; H04B1/40; H04B1/54; H04B1/58; H04B1/587
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
142 words
A device for coupling between electrical communication lines comprising: first circuit means containing a first pair of electrical communication wires and a first portion of a hybrid circuit means terminating said first pair of wires; second circuit means containing a second pair of electrical communication wires, a third pair of electrical communication wires and a second portion of said hybrid circuit means terminating said second and third pairs of wires; said first and second hybrid circuit means enabling bidirectional communication between said first and second circuit means included in said first and second portions of said hybrid circuit means; and optical coupling means for providing D.C. isolation between the wires of said first, second and third pairs and A.C. balance between the wires of said first pair, between the wires of said second pair and between the wires of said third pair.
Claim 2
Independent Claim
142 words
A device for coupling between electrical communication lines comprising: first circuit means containing a first pair of electrical communication wires and a first portion of a hybrid circuit means terminating said first pair of wires; second circuit means containing a second pair of electrical communication wires, a third pair of electrical communication wires and a second portion of said hybrid circuit means terminating said second and third pairs of wires; said first and second hybrid circuit means enabling bidirectional communication between said first and second circuit means included in said first and second portions of said hybrid circuit means; and optical coupling means for providing D.C. isolation between the wires of said first, second and third pairs and A.C. balance between the wires of said first pair, between the wires of said second pair and between the wires of said third pair.
Claim 3
Dependent Claim
15 words
The device of claim 1 wherein said first circuit means comprises a two-wire telephone circuit.
Claim 4
Dependent Claim
15 words
The device of claim 1 wherein said second circuit means comprises a four-wire telephone circuit.
Claim 5
Dependent Claim
24 words
The device of claim 1 wherein said optical coupling means comprises at least one light emissive means and at least one light responsive means.
Claim 6
Dependent Claim
22 words
The device of claim 4 wherein said light emissive means and said light responsive means are coupled together by light conducting fibers.
Claim 7
Dependent Claim
17 words
The device of claim 4 wherein said light emissive means comprises at least one light emitting diode.
Claim 8
Dependent Claim
15 words
The device of claim 4 wherein said light responsive means comprises at least one phototransistor.
Claim 9
Dependent Claim
28 words
The device of claim 1 wherein said optical coupling means comprises light emissive means in said first circuit means and light responsive means in said second circuit means.
Claim 10
Dependent Claim
66 words
The device of claim 1 wherein said optical coupling means comprises a first light responsive means and a first light emissive means in said first circuit means and a second light responsive means in an optically coupled relation with said first light emissive means and a second light emissive means in an optically coupled relation with said first light responsive means in said second circuit means.
Claim 11
Independent Claim
253 words
A device for bidirectional communication between a pair of spaced circuits having a hybrid circuit means comprising in combination: a first pair of wires coupled to one of said pair of circuits and terminated by a first portion of said hybrid circuit means, said first pair of wires providing a first electrical communication line, said first portion of said hybrid circuit means having light emissive means in one of said first wires and light responsive means in the other of said first wires; a second pair of wires coupled to the other of said pair of circuits and terminated by a second portion of said hybrid circuit means, said second pair of wires providing a second electrical communication line, said second portion of said hybrid circuit means having light responsive means in said second line; and a third pair of wires coupled to said other of said pair of circuits and terminated by a third portion of said hybrid circuit means, said third pair of wires providing a third electrical communication line, said third portion of said hybrid circuit means having light emissive means in said third line said light emissive means in said first wires energizing said light responsive means in said second line, and said light emissive means in said third line energizing said light responsive means in said first wires, for providing said bidirectional communication and A.C. balance between the wires of said first pair, between the wires of said second pair and between the wires of said third pair.
Claim 12
Independent Claim
253 words
A device for bidirectional communication between a pair of spaced circuits having a hybrid circuit means comprising in combination: a first pair of wires coupled to one of said pair of circuits and terminated by a first portion of said hybrid circuit means, said first pair of wires providing a first electrical communication line, said first portion of said hybrid circuit means having light emissive means in one of said first wires and light responsive means in the other of said first wires; a second pair of wires coupled to the other of said pair of circuits and terminated by a second portion of said hybrid circuit means, said second pair of wires providing a second electrical communication line, said second portion of said hybrid circuit means having light responsive means in said second line; and a third pair of wires coupled to said other of said pair of circuits and terminated by a third portion of said hybrid circuit means, said third pair of wires providing a third electrical communication line, said third portion of said hybrid circuit means having light emissive means in said third line said light emissive means in said first wires energizing said light responsive means in said second line, and said light emissive means in said third line energizing said light responsive means in said first wires, for providing said bidirectional communication and A.C. balance between the wires of said first pair, between the wires of said second pair and between the wires of said third pair.
Claim 13
Dependent Claim
89 words
The device of claim 10 including light emissive means coupled in series with the emitter-collector path of a first transistor in said one of said first wires and light emissive means coupled in series with the emitter-collector path of a second transistor in said other of said first wires, said light emissive means in said one of said first wires having opposite electrical polarity with respect to the polarity of said light emissive means in said other of said first wires for providing electrical balance between said first wires.
Claim 14
Dependent Claim
58 words
The device of claim 10 wherein: said light emissive means in said third line comprises a pair of light emitting diodes; said light responsive means in said second line comprise a pair of phototransistors; and said second line and said third line are coupled together by resistance means for providing electrical balance between said second and third lines.
Claim 15
Dependent Claim
63 words
The device of claim 10 wherein said light emissive means in said one of said first wires is coupled to said light responsive means said second line by means of optical communication fibers, and wherein said light responsive means in said other of said first wires is coupled to said light emissive means in said third line by means of optical communication fibers.
Claim 16
Dependent Claim
30 words
The device of claim 13 wherein said optical communication fibers comprise light transparent material having a high index core and a cladding of lower index of refraction than said core.
Claim 17
Independent Claim
289 words
A device for bidirectional communication between a first pair of electrical communication wires and a second and third pair of electrical communication wires, said first, second and third pair of wires being terminated in a hybrid circuit means to enable said bidirectional communication, said hybrid circuit means comprising in combination: a first light emitting diode and a first phototransistor connected in series and a first transistsor having its base-collector path in parallel with said first phototransistor and its emitter coupled to said first diode in one of said first wires and a second light emitting diode and a second phototransistor connected in series and a second transistor having its base-collector path in parallel with said second phototransistor and in series with said second diode and its emitter coupled to the other of said first wires, said second light emitting diode and said second phototransistor having opposite polarity from said first light emitting diode and said first phototransistor for providing electrical balance between said first wires; and a pair of light emitting diodes serially connected in one of said third wires and a pair of phototransistors serially connected in one of said second wires, said one of said third wires and said one of said second wires being connected together by resistance means for providing electrical balance therebetween; where light generated by said first and second light emitting diodes energizes said pair of phototransistors in said one of said second wires, and A.C. noise generated within said first wires is isolated from said second wires; and where light generated by said pair of light emitting diodes in said third wires energizes said first and second phototransistors, and A.C. noise generated within said third wires is isolated from said first wires.
Claim 18
Independent Claim
289 words
A device for bidirectional communication between a first pair of electrical communication wires and a second and third pair of electrical communication wires, said first, second and third pair of wires being terminated in a hybrid circuit means to enable said bidirectional communication, said hybrid circuit means comprising in combination: a first light emitting diode and a first phototransistor connected in series and a first transistsor having its base-collector path in parallel with said first phototransistor and its emitter coupled to said first diode in one of said first wires and a second light emitting diode and a second phototransistor connected in series and a second transistor having its base-collector path in parallel with said second phototransistor and in series with said second diode and its emitter coupled to the other of said first wires, said second light emitting diode and said second phototransistor having opposite polarity from said first light emitting diode and said first phototransistor for providing electrical balance between said first wires; and a pair of light emitting diodes serially connected in one of said third wires and a pair of phototransistors serially connected in one of said second wires, said one of said third wires and said one of said second wires being connected together by resistance means for providing electrical balance therebetween; where light generated by said first and second light emitting diodes energizes said pair of phototransistors in said one of said second wires, and A.C. noise generated within said first wires is isolated from said second wires; and where light generated by said pair of light emitting diodes in said third wires energizes said first and second phototransistors, and A.C. noise generated within said third wires is isolated from said first wires.
Claim 19
Dependent Claim
41 words
The device of claim 15 wherein said light emitting diodes and said phototransistors are coupled together by means of light conducting fibers, said light conducting fibers comprising a high index of refraction core material and a low index of refraction cladding.
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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) | 1979-10-19 | 1980-04-19 | 1980-10-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-10-19 | 1984-04-19 | 1984-10-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-10-19 | 1988-04-19 | 1988-10-19 | $7700.00 | Window Closed / Lapsed |