Patent US5333089A successfully refreshed from Google Patents.
US5333089A
Expired / Lapsed
US
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Optical communications system employing fiber-optic amplifiers and control of the transmitter wavelength
Assignee: Alcatel Lucent NV
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Filing: 1993-02-19
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Granted: 1994-07-26
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Expires: 2013-02-19
Abstract
Abstract An optical communications system includes an optical transmitter equipped with a semiconductor laser for generating a light signal and a light waveguide path for transmitting the generated light signal to an optical receiver in whose light waveguide path at least one fiber-optic amplifier is included. The fiber-optic amplifier is equipped with an amplifying light waveguide piece. The optical transmitter includes a control device having a reference waveguide piece, which regulates an emission wavelength of the semiconductor laser in dependence on absorption of the light signal in the reference light waveguide piece. The reference waveguide piece has a maximum in absorption at a wavelength at which the amplifying light waveguide piece of the at least one fiber-optic amplifier has a maximum in emission.
Inventors
- 👤 Rolf Heidemann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 07:17
CPC Classifications
H; H04; H04B; H04B10/00; H04B10/29; H04B10/291; H04B10/2912; H01; H01S; H01S3/00; H01S3/05; H01S3/06; H01S3/063; H01S3/067; H01S3/06754; H01S3/06758; H04B10/50; H04B10/501; H04B10/503; H04B10/504; H04B10/572; H04B2210/00; H04B2210/003
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
122 words
An optical communications system comprising: an optical transmitter including a semiconductor laser for generating a light signal; a light waveguide path for transmitting the generated light signal; and an optical receiver for receiving the transmitted light signal from the light waveguide path and having at least one fiber-optic amplifier including an amplifying light waveguide piece, wherein the optical transmitter includes a control device having a reference waveguide piece, which regulates an emission wavelength of the semiconductor laser in dependence on absorption of the light signal in the reference light waveguide piece, the reference waveguide piece having a maximum in absorption at a wavelength at which the amplifying light waveguide piece of the at least one fiber-optic amplifier has a maximum in emission.
Claim 2
Dependent Claim
122 words
An optical communications system comprising: an optical transmitter including a semiconductor laser for generating a light signal; a light waveguide path for transmitting the generated light signal; and an optical receiver for receiving the transmitted light signal from the light waveguide path and having at least one fiber-optic amplifier including an amplifying light waveguide piece, wherein the optical transmitter includes a control device having a reference waveguide piece, which regulates an emission wavelength of the semiconductor laser in dependence on absorption of the light signal in the reference light waveguide piece, the reference waveguide piece having a maximum in absorption at a wavelength at which the amplifying light waveguide piece of the at least one fiber-optic amplifier has a maximum in emission.
Claim 3
Dependent Claim
90 words
A system according to claim 1, further comprising: coupling means for coupling part of the light signal generated by the semiconductor laser into the reference light waveguide piece; and wherein the control device includes: a photodetector which converts a light signal exiting the reference light waveguide piece into an electrical signal proportional to the intensity thereof; and a control circuit which regulates an emission wavelength of the semiconductor laser based on the electrical signal so that the light signal coupled into the reference light waveguide piece is maximally absorbed therein.
Claim 4
Dependent Claim
45 words
A system according to claim 2, wherein the optical transmitter control circuit includes control means for controlling the temperature of the semiconductor laser, wherein the control device regulates an emission wavelength of the laser by controlling the temperature of the laser with the control means.
Claim 5
Dependent Claim
23 words
A system according to claim 3, wherein the control device regulates the emission wavelength by controlling the mean operating current of the laser.
Claim 6
Dependent Claim
61 words
A system according to claim 3, wherein the control circuit modulates the emission wavelength of the laser with a very low frequency and derives a control signal from a variation of an output signal of the photodetector occurring in response that shifts the emission wavelength so that absorption of the light signal in the reference light waveguide piece attains a maximum.
Claim 7
Dependent Claim
115 words
An optical transmitter comprising: a semiconductor laser for generating a light signal for an optical communications system, the optical communications system including a light waveguide path for transmitting the generated light signal to an optical receiver, at least one fiber-optic amplifier including an amplifying light waveguide piece being inserted into said light waveguide path; and a control device having a reference light waveguide piece, which regulates an emission wavelength of the semiconductor laser as a function of absorption of the light signal in the reference light waveguide piece having a maximum in absorption at a wavelength at which the amplifying light waveguide piece of the at least one fiber-optic amplifier has a maximum in emission.
Claim 8
Dependent Claim
115 words
An optical transmitter comprising: a semiconductor laser for generating a light signal for an optical communications system, the optical communications system including a light waveguide path for transmitting the generated light signal to an optical receiver, at least one fiber-optic amplifier including an amplifying light waveguide piece being inserted into said light waveguide path; and a control device having a reference light waveguide piece, which regulates an emission wavelength of the semiconductor laser as a function of absorption of the light signal in the reference light waveguide piece having a maximum in absorption at a wavelength at which the amplifying light waveguide piece of the at least one fiber-optic amplifier has a maximum in emission.
Claim 9
Dependent Claim
90 words
An optical transmitter according to claim 6, further comprising: coupling means for coupling part of the light signal generated by the semiconductor laser into the reference light waveguide piece; and wherein the control device includes: a photodetector which converts a light signal exiting the reference light waveguide piece into an electrical signal proportional to its intensity; and a control circuit which regulates an emission wavelength of the semiconductor laser based on the electrical signal so that the light signal coupled into the reference light waveguide piece is maximally absorbed therein.
Claim 10
Dependent Claim
42 words
An optical transmitter according to claim 7, further comprising control means for controlling the temperature of the semiconductor laser wherein the control device regulates the emission wavelength of the semiconductor laser by controlling the temperature of the laser with the control means.
Claim 11
Dependent Claim
24 words
An optical transmitter according to claim 7, wherein the control device regulates the emission wavelength by controlling a mean operating current of the laser.
Claim 12
Dependent Claim
63 words
An optical transmitter according to claim 8, wherein the control device modulates the emission wavelength of the semiconductor laser with a very low frequency and derives a control signal from a variation of an output signal of the photodetector occurring in response that shifts the emission wavelength so that absorption of the light signal in the reference light waveguide piece attains a maximum.
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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) | 1997-07-25 | 1998-01-24 | 1998-07-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-07-25 | 2002-01-24 | 2002-07-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-07-25 | 2006-01-24 | 2006-07-26 | $7700.00 | Window Closed / Lapsed |