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Interferometric devices for reducing harmonic distortions in laser communication systems

Assignee: Nokia Bell Labs
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Filing: 1989-08-31
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Granted: 1991-03-26
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Expires: 2009-08-31
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Abstract

Abstract In an optical communication system, in order to reduce simultaneously both second and third harmonic distortion in a light beam from a modulated semiconductor laser, a nonlinear interferometric deivce--such as a Fabry-Perot etalon--is inserted in the path of the beam. The parameters of the interferometric device--such as its phase and finesse--are selected such that, for a suitable laser bias current, the second and third harmonics produced by nonlinearities of the laser (plus nonlinearities of the transmission medium such as an optical fiber, if any, through which the beam propagates from source to receiver) are significantly compensated by nonlinearities of the interometric device.

Inventors

  • 👤 Anne I. Lidgard
  • 👤 Nils A. Olsson

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 04:23
CPC Classifications
H; H01; H01S; H01S5/00; H01S5/06; H01S5/068; H01S5/0683; H01S5/0687

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 76 words
An optical transmission system comprising (a) a semiconductor injection laser which emits an optical beam which is modulated by means of signals applied to the laser, whereby the laser emits a modulated optical beam; (b) an optical interferometric device located in the path of the modulated beam so as to reduce harmonic distortion in the beam, the interferometric device being a Fabry-Perot etalon having opposing faces each with a reflectivity of less than about 10 percent.
Claim 2
Dependent Claim 76 words
An optical transmission system comprising (a) a semiconductor injection laser which emits an optical beam which is modulated by means of signals applied to the laser, whereby the laser emits a modulated optical beam; (b) an optical interferometric device located in the path of the modulated beam so as to reduce harmonic distortion in the beam, the interferometric device being a Fabry-Perot etalon having opposing faces each with a reflectivity of less than about 10 percent.
Claim 3
Dependent Claim 33 words
The system of claim 1 in which the phase of the interferometric device is selected to minimize simultaneously second and third harmonic distortions, and in which the laser is a semiconductor injection laser.
Claim 4
Dependent Claim 21 words
The system of claim 2 further comprising an optical fiber located to receive and transmit optical radiation coming from the laser.
Claim 5
Dependent Claim 15 words
The system of claim 3 further comprising means for detecting light coming from the fiber.
Claim 6
Dependent Claim 18 words
The system of claim 3 further comprising means for detecting and utilizing the light coming from the fiber.
Claim 7
Dependent Claim 21 words
The system of claim 1 further comprising an optical fiber located to receive and transmit optical radiation coming from the laser.
Claim 8
Dependent Claim 15 words
The system of claim 6 further comprising means for detecting light coming from the fiber.
Claim 9
Dependent Claim 18 words
The system of claim 6 further comprising means for detecting and utilizing the light coming from the fiber.

References Cited (Backward Citations)

US4101847A Cited
US4561119A Cited
US4847477A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1994-03-25 1994-09-24 1995-03-26 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1998-03-25 1998-09-24 1999-03-26 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2002-03-25 2002-09-24 2003-03-26 $7700.00 Window Closed / Lapsed

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