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US5706301A
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Laser wavelength control system
Assignee: Telefonaktiebolaget LM Ericsson AB
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Filing: 1995-08-16
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Granted: 1998-01-06
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Expires: 2015-08-16
Abstract
Abstract A laser wavelength control system (20) stabilizes laser output wavelength. The control system includes a reflector/filter device (40) upon which laser radiation is incident for yielding both a filtered-transmitted signal (FS) and a reflected signal (RS). A controller (45) uses both the filtered-transmitted signal (FS) and the reflected signal (RS) to generate a control signal (CS). The control signal is utilized by a temperature converter (100) to adjust laser output wavelength of the laser (22). In one embodiment, the reflector/filter device is an optical fiber grating. The wavelength control system facilitates construction of a modular optical multichannel transmission system (200).
Inventors
- 👤 Bo E. Lagerstrom
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 05:58
CPC Classifications
H; H01; H01S; H01S5/00; H01S5/06; H01S5/068; H01S5/0683; H01S5/0687; H01S3/00; H01S3/10; H01S3/13; H01S3/139; H01S3/1392; H01S5/06837
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
97 words
A laser wavelength control system for stabilizing laser output wavelength from a laser which generates laser output radiation, the system comprising: a reflector/filter device upon which the laser output radiation is at least partially incident for yielding both a filter-transmitted signal and a reflected signal; a controller which utilizes both the filter-transmitted signal and the reflected signal to generate a control signal for use in stabilizing the laser output wavelength; wherein the controller generates the control signal based on a zero crossing point of the control signal in a neighborhood of smooth slope of the control signal.
Claim 2
Dependent Claim
97 words
A laser wavelength control system for stabilizing laser output wavelength from a laser which generates laser output radiation, the system comprising: a reflector/filter device upon which the laser output radiation is at least partially incident for yielding both a filter-transmitted signal and a reflected signal; a controller which utilizes both the filter-transmitted signal and the reflected signal to generate a control signal for use in stabilizing the laser output wavelength; wherein the controller generates the control signal based on a zero crossing point of the control signal in a neighborhood of smooth slope of the control signal.
Claim 3
Dependent Claim
33 words
The system of claim 1, wherein the controller comprises a temperature converter which uses the control signal to generate a laser temperature feedback signal for adjusting the laser output wavelength of the laser.
Claim 4
Dependent Claim
53 words
The system of claim 1, wherein the controller comprises a signal processor, and wherein the signal processor comprises: a first detector for detecting the filter-transmitted signal; a second detector for detecting the reflected signal; and an analog circuit which compares the filter-transmitted signal and the reflected signal for generation of the control signal.
Claim 5
Dependent Claim
53 words
The system of claim 1, wherein the controller comprises a signal processor, and wherein the signal processor comprises: a first detector for detecting the filter-transmitted signal; a second detector for detecting the reflected signal; and a digital processor which compares the filter-transmitted signal and the reflected signal for generation of the control signal.
Claim 6
Dependent Claim
14 words
The system of claim 1, wherein the reflector/filter device is an optical fiber grating.
Claim 7
Dependent Claim
85 words
A laser wavelength control method for stabilizing laser output wavelength, the method comprising: directing laser output radiation from a laser to a reflector/filter device which yields both a filter-transmitted signal and a reflected signal; utilizing both the filter-transmitted signal and reflected signal to generate a control signal; using the control signal for stabilizing the output wavelength of the laser; wherein the control signal is generated based on a zero crossing point of the control signal in a neighborhood of smooth slope of the control signal.
Claim 8
Dependent Claim
85 words
A laser wavelength control method for stabilizing laser output wavelength, the method comprising: directing laser output radiation from a laser to a reflector/filter device which yields both a filter-transmitted signal and a reflected signal; utilizing both the filter-transmitted signal and reflected signal to generate a control signal; using the control signal for stabilizing the output wavelength of the laser; wherein the control signal is generated based on a zero crossing point of the control signal in a neighborhood of smooth slope of the control signal.
Claim 9
Dependent Claim
27 words
The method of claim 6, further comprising using the control signal to generate a laser temperature feedback signal for adjusting the laser output wavelength of the laser.
Claim 10
Dependent Claim
109 words
A laser wavelength control system for stabilizing laser output wavelength from a laser which generates laser output radiation, the system comprising: a reflector/filter device upon which the laser output radiation is at least partially incident, the reflector/filter having a transfer function which yields both a filter-transmitted signal and a reflected signal; a controller which utilizes both the filter-transmitted signal and the reflected signal to generate an error signal, the error signal in turn being utilized by the controller to generate a control signal having a zero-crossing point in a neighborhood of smooth slope of the transfer function, the controller using the control signal for stabilizing the laser output wavelength.
Claim 11
Dependent Claim
109 words
A laser wavelength control system for stabilizing laser output wavelength from a laser which generates laser output radiation, the system comprising: a reflector/filter device upon which the laser output radiation is at least partially incident, the reflector/filter having a transfer function which yields both a filter-transmitted signal and a reflected signal; a controller which utilizes both the filter-transmitted signal and the reflected signal to generate an error signal, the error signal in turn being utilized by the controller to generate a control signal having a zero-crossing point in a neighborhood of smooth slope of the transfer function, the controller using the control signal for stabilizing the laser output wavelength.
Claim 12
Dependent Claim
33 words
The system of claim 8, wherein the controller comprises a temperature converter which uses the control signal to generate a laser temperature feedback signal for adjusting the laser output wavelength of the laser.
Claim 13
Dependent Claim
53 words
The system of claim 8, wherein the controller comprises a signal processor, and wherein the signal processor comprises: a first detector for detecting the filter-transmitted signal; a second detector for detecting the reflected signal; and an analog circuit which compares the filter-transmitted signal and the reflected signal for generation of the control signal.
Claim 14
Dependent Claim
53 words
The system of claim 8, wherein the controller comprises a signal processor, and wherein the signal processor comprises: a first detector for detecting the filter-transmitted signal; a second detector for detecting the reflected signal; and a digital processor which compares the filter-transmitted signal and the reflected signal for generation of the control signal.
Claim 15
Dependent Claim
14 words
The system of claim 8, wherein the reflector/filter device is an optical fiber grating.
Claim 16
Dependent Claim
90 words
A laser wavelength control method for stabilizing laser output wavelength, the method comprising: directing laser output radiation from a laser to a reflector/filter device, the reflector/filter device having a transfer function which yields both a filter-transmitted signal and a reflected signal; utilizing both the filter-transmitted signal and reflected signal to generate an error signal; utilizing the error signal to generate a control signal having a zero-crossing point in a neighborhood of smooth slope of the transfer function; and using the control signal for stabilizing the output wavelength of the laser.
Claim 17
Dependent Claim
90 words
A laser wavelength control method for stabilizing laser output wavelength, the method comprising: directing laser output radiation from a laser to a reflector/filter device, the reflector/filter device having a transfer function which yields both a filter-transmitted signal and a reflected signal; utilizing both the filter-transmitted signal and reflected signal to generate an error signal; utilizing the error signal to generate a control signal having a zero-crossing point in a neighborhood of smooth slope of the transfer function; and using the control signal for stabilizing the output wavelength of the laser.
Claim 18
Dependent Claim
27 words
The method of claim 13, further comprising using the control signal to generate a laser temperature feedback signal for adjusting the laser output wavelength of the laser.
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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) | 2001-01-05 | 2001-07-07 | 2002-01-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-01-05 | 2005-07-07 | 2006-01-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-01-05 | 2009-07-07 | 2010-01-06 | $7700.00 | Window Closed / Lapsed |