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WO1996036859A1 - Mesure de la dispersion en mode de polarisation - Google Patents

Mesure de la dispersion en mode de polarisation Download PDF

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Publication number
WO1996036859A1
WO1996036859A1 PCT/US1996/007197 US9607197W WO9636859A1 WO 1996036859 A1 WO1996036859 A1 WO 1996036859A1 US 9607197 W US9607197 W US 9607197W WO 9636859 A1 WO9636859 A1 WO 9636859A1
Authority
WO
WIPO (PCT)
Prior art keywords
mode dispersion
polarization mode
artefact
fiber
birefringent
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/US1996/007197
Other languages
English (en)
Inventor
Terry L. Voots
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from US08/445,320 external-priority patent/US5654793A/en
Application filed by Individual filed Critical Individual
Priority to AU60228/96A priority Critical patent/AU6022896A/en
Priority to JP08535104A priority patent/JP2000510573A/ja
Publication of WO1996036859A1 publication Critical patent/WO1996036859A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
    • G01M11/00—Testing of optical apparatus; Testing structures by optical methods not otherwise provided for
    • G01M11/30—Testing of optical devices, constituted by fibre optics or optical waveguides
    • G01M11/33—Testing of optical devices, constituted by fibre optics or optical waveguides with a light emitter being disposed at one fibre or waveguide end-face, and a light receiver at the other end-face
    • G01M11/336—Testing of optical devices, constituted by fibre optics or optical waveguides with a light emitter being disposed at one fibre or waveguide end-face, and a light receiver at the other end-face by measuring polarization mode dispersion [PMD]
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
    • G01J4/00—Measuring polarisation of light
    • G01J4/04—Polarimeters using electric detection means
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
    • G01M11/00—Testing of optical apparatus; Testing structures by optical methods not otherwise provided for
    • G01M11/30—Testing of optical devices, constituted by fibre optics or optical waveguides
    • G01M11/33—Testing of optical devices, constituted by fibre optics or optical waveguides with a light emitter being disposed at one fibre or waveguide end-face, and a light receiver at the other end-face
    • G01M11/331—Testing of optical devices, constituted by fibre optics or optical waveguides with a light emitter being disposed at one fibre or waveguide end-face, and a light receiver at the other end-face by using interferometer

Definitions

  • the present invention relates to a method for testing optical fibers, and more particularly to a method for measuring at high resolution Polarization Mode Dispersion (PMD) values in single mode optical fibers.
  • PMD Polarization Mode Dispersion
  • Polarization Mode Dispersion measurement instruments are known in the art, and particularly defined in draft standards of the Telecommunications Industries Association, headquartered in Arlington, Virginia. These standards include Fiber Optic Test Procedure FOTP-113 for Polarization-Mode Dispersion Measurement for Single-Mode Optical Fibers by Wavelength Scanning, FOTP-122 for
  • Polarization Mode Dispersion Measurement for Single-Mode Optical Fibers by Jones Matrix Eigenanalysis, and FOTP-124 for Polarization-Mode Dispersion Measurement for Single-Mode Optical Fibers by Interferometric Method The detailed operation and procedure of the Polarization Mode Dispersion measurement instrument is described in these standards.
  • Polarization Mode Dispersion measurement instruments include cycle counting, time pulse methods, relative phase methods or Jones Matrix Eigenanalysis, as discussed in more detail below.
  • Jones describes a known method for measuring dispersion in optical ⁇ fibers.
  • Jones describes a relative-phase method and apparatus for measuring transmissive dispersion,- such as chromatic or polarization dispersion.
  • a light source 5 modulated at a first frequency is synchronously varied at a lower frequency back and forth to and from a first and a second value of a transmission parameter, e.g. source wavelength or polarization state.
  • Relative phases of the first modulation signal and the light transmitted through the 10 fiber under test are measured by a phase detector.
  • a lock-in amplifier compares the phase detector output to the lower frequency signal to provide a direct current output indicative of dispersion.
  • Another method for measuring dispersion in optical fibers 15 measures time differences.
  • the Jones Matrix Eigenanalysis method measures DGD ⁇ as a function of wavelength, where DGD is known as a differential group delay, and PMD is expressed as ⁇ ⁇ T > ⁇ .
  • the relative-phase method and apparatus described in Jones proved to be superior in resolution than the method 20 for measuring time differences.
  • Interferometry 25 uses the time domain to employ a low-coherence light source and a Michelson* or Mach-Zehnder Interf rometer to observe output in the form of the autocorrelation function of the time distribution, and the Polarization Mode Dispersion of the fiber may be obtained from this data.
  • Interferometry is limited at the low end by the coherence time, typically 0.15 picoseconds, of the broadband source used.
  • Jones Matrix Eigenanalysis uses a polarimetric determination of the instantaneous polarization transmission behavior, in the form of a Jones matrix with two eigenstates called Principal States of Polarization (PSP) .
  • PSP Principal States of Polarization
  • the different delays between PSPs may be determined. The delay is averaged over " a specific wavelength scan to establish the fiber Polarization Mode Dispersion value.
  • Jones Matrix Eigenanalysis is limited by polarimetric accuracy and resolution to 0.01 picoseconds.
  • the WS cycle counting and the WS Fourier methods both use a light power transmission through the fiber using a linearly polarized source and a polarization analyzer before the light detector.
  • the fiber gives rise to an oscillation pattern whose oscillation frequency is related to Polarization Mode Dispersion.
  • the number of complete oscillations in a given wavelength interval is . counted to determine Polarization-Mode Dispersion.
  • the WS cycle counting method is limited to a minimum of three cycles- in the wavelength scan, typically 0.09 picoseconds.
  • wavelength scanning Polarization Mode Dispersion is determined by a frequency analysis technique on the oscillation pattern based on a Fourier transform.
  • the Fourier method is limited to a minimum of one cycle in the wavelength scan used, typically 0.03 picoseconds.
  • a method for improving the measurement of Polarization Mode Dispersion by incorporating an artefact with a stable known Polarization Mode Dispersion value in a Polarization Mode Dispersion measuring instrument, and having a light source transmit light serially through an optic fiber to be tested and the artefact.
  • the artefact biases a total Polarization Mode Dispersion measured by the Polarization Mode Dispersion measuring instrument away from zero, thus removing the undesirable influence of any spurious (near-zero) Polarization Mode Dispersion response from the measurement.
  • the Polarization Mode Dispersion of the optic fiber may then be accurately determined by appropriate data processing of the measured Polarization Mode Dispersion.
  • the artefact may also be used to calibrate a wavelength scanning Polarization Mode Dispersion instrument.
  • the invention enables a high resolution measurement of Polarization Mode Dispersion with at least one order of magnitude higher, and possibly two orders of magnitude higher, than that achievable with the prior art relative phase or tim measurement system.
  • Figure 1 is a block diagrammatic representation of a Polarization Mode Dispersion measurement instrument in accordance with the present invention utilizing a Mach-Zehnder interferometer.
  • Figure 2 is a block diagrammatic representation of a
  • Polarization Mode Dispersion measurement instrument in accordance with another embodiment of the present invention suitable for use with wavelength scanning Fourier analysis (WS Fourier) .
  • Figure 3a is a graph of time versus Polarization Mode
  • Figure 3b is a graph of time versus Polarization Mode Dispersion value for a Polarization Mode Dispersion measurement instrument of the present invention.
  • Figure 4 is a block diagram of an application of the present invention to calibrate a Polarization Mode Dispersion instrument.
  • Figures 1 and 2 are block diagrams of two Polarization Mode Dispersion measurement instruments for high resolution, polarization dispersion measurement, which are the subject of the present invention.
  • Figure 1 shows one Polarization Mode Dispersion measurement instrument using an interferometric measurement technique
  • Figure 2 shows another Polarization Mode Dispersion measurement instrument using a wavelength scanning Fourier analysis (WS Fourier) technique.
  • the Polarization Mode Dispersion measurement instrument has a light source 10 which may be either a light emitting diode (LED) , as shown, or in an alternative embodiment, a superfluorescent light source (not shown) .
  • LED light emitting diode
  • superfluorescent light source not shown
  • the Polarization Mode Dispersion measurement instrument has a polarizer 12 that responds to light coming from an output of the light source 10, for providing polarized light.
  • a beam splitter 14 connected to the polarizer 12 divides the polarized light for transmission in a first path 16 and a second path 18.
  • the second path 18 includes a delay line 20 for delaying the transmission of light.
  • the delay line 20 can be adjusted to alter a relative optical delay between the first -and second paths 16 and 18.
  • the delay line 20 is a Mach-Zehnder interferometer, which is known in the art.
  • a beam splitter 22 receives light transmitted along the first and second paths 18 and 20 and delivers it to an artefact 28.
  • the artefact 28 is a -device which produces a known, stable Polarization Mode Dispersion.
  • the artefact 28 will assure that the Polarization Mode Dispersion measurement ? instrument will have a known interference peak level at a particular time value T, as best shown in Figure 3b.
  • the artefact 28 is a birefringent device, which may be a birefringent waveplate, birefringent fiber or other birefringent device.
  • the time T is the time difference between the fast and slow polarization modes, or simply the Polarization Mode Dispersion of the artefact 28.
  • the artefact 28 serves to bias the total Polarization Mode Dispersion measured by the instrument away from zero, removing the influence of any spurious (near-zero) Polarization Mode Dispersion response from the measurement, as shown in Figure 3b.
  • a test fiber 26 receives light from an output of the 5 artefact 28.
  • the connection between the artefact 28 and the test fiber 26 is known in the art, and may include a lens system, a butt splice to a single mode fiber pigtail or an index-matched coupling.
  • the scope of the invention is not intended to be limited to any particular series 0 arrangement between the artefact 28 and the test fiber 26.
  • the artefact 28 is arranged before the test fiber 26 in Figure 1, while in Figure 2, the artefact 60 is arranged after the test fiber 56.
  • Such a construction could also be incorporated in .accordance with these teachings
  • An output of the fiber 26 is delivered to an analyzer 30 that observes interferences between principal orthogonal states of polarization, and provides an analyzed signal to a detector 32, that represents polarization states versus power.
  • the detector 32 converts an optical signal to an electrical, signal.
  • a polarimeter may be used.
  • a lock-in amplifier 34 is a synchronized phase and volt meter which is used to demodulate chopped or modulated optical signals for signal processing.
  • a computer 36 provides electronic signal processing and apparatus control functions. The interference signature versus the setting of the delay line 20 is determined and stored using a standard computer 36.
  • FIG. 2 shows an alternative embodiment of the present invention in which the Polarization Mode Dispersion measurement instrument has an artefact 60 coupled to an output of a test fiber 56.
  • a light source 50 delivers light to a polarizer 52 for coupling through a splice 54 to a fiber under test 56.
  • a splice 58 couples an output of the test fiber 56 to the artefact 60.
  • An analyzer 62 analyses the light polarization state, and an optical spectrum analyzer or monochromator 64 allows the polarization transmission versus optical wavelength to be measured.
  • the computer 68 performs a Fourier analysis and apparatus control functions, and Polarization Mode Dispersion calculations.
  • the artefact 60 produces a known, stabie Polarization Mode Dispersion. It will assure that the Polarization Mode Dispersion measurement output will have a known peak level at a particular time value T.
  • the artefact 60 may be a birefringent device, which may be a birefringent waveplate, birefringent fiber or other ) birefringent device.
  • the time T is the time difference between the fast and slow polarization modes, or simply the.
  • the artefact 60 may also be a reflective or transmissive device which provides a known stable sinusoidal response of power versus wavelength indicative of the insertion loss spectrum of the artefact.
  • An example of either artefact 60 is a Fabry-Perot etalon, 10 including an interferometer. The sinusoidal response of power versus wavelength will give an apparent Polarization Mode Dispersion peak at time T, corresponding to the known, stable insertion loss spectrum of the artefact.
  • the basic Polarization Mode Dispersion signature is transposed by the artefact 28 or 60 from zero to time T.
  • the spurious effects do not interact with the measured dispersion.
  • the spurious responses do not affect measurement of Polarization Mode Dispersion during a calculation of the width, e.g. Root Mean Square width, of the measured peak.
  • Figure 4 shows a calibration of a Polarization Mode Dispersion in accordance with the present invention.
  • a test fiber is not included in the light path.
  • An artefact 106 is included, which receives light transmitted from a broadband source 100 through a polarizer 102 coupled to a splice 104.
  • a splice- 108 couples the output- of the artefact 106 to an analyzer 110 whose output is analyzed by a measuring means 112 comprising an optical spectrum analyzer or monochromator and computation means 114 operating in* accordance with the principles described with respect to Figure 2.
  • the artefact 104 will bias the measured Polarization Mode Dispersion away from zero.
  • the measured Polarization Mode Dispersion is compared to the known Polarization Mode Dispersion value of the artefact 104.
  • the Polarization Mode Dispersion apparatus produces a Polarization Mode Dispersion signature at time T equivalent to the known, stable insertion loss spectrum of the artefact in accordance with the principles described with respect to Figure 2.
  • the above teachings will enable those skilled in the art to provide many different embodiments of high resolution measuring means which can employ wavelength transmissive devices for the artefact.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Chemical & Material Sciences (AREA)
  • Optics & Photonics (AREA)
  • Analytical Chemistry (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Dispersion Chemistry (AREA)
  • Investigating Or Analysing Materials By Optical Means (AREA)
  • Testing Of Optical Devices Or Fibers (AREA)
  • Investigating Or Analyzing Materials Using Thermal Means (AREA)
  • Spectrometry And Color Measurement (AREA)

Abstract

Procédé permettant d'effectuer la mesure à haute résolution de la dispersion en mode de polarisation d'une fibre optique (26). Ce procédé consiste à utiliser un instrument de mesure de la dispersion en mode de polarisation comprenant une source de lumière (10); à utiliser une fibre test (26); à disposer en série avec la fibre test (26) un artefact (28) possédant une valeur de dispersion en mode de polarisation stable et connue; à mesurer une valeur soumise à polarisation de la dispersion en mode de polarisation avec l'instrument de mesure de la dispersion en mode de polarisation, polarisée loin d'une valeur zéro de la dispersion en mode de polarisation; et à déterminer la dispersion en mode de polarisation de la fibre optique à partir de la valeur soumise à polarisation mesurée de la dispersion en mode de polarisation.
PCT/US1996/007197 1995-05-19 1996-05-17 Mesure de la dispersion en mode de polarisation Ceased WO1996036859A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
AU60228/96A AU6022896A (en) 1995-05-19 1996-05-17 Measurement of polarization mode dispersion
JP08535104A JP2000510573A (ja) 1995-05-19 1996-05-17 単一モード光ファイバ内の非常に低いレベルの偏波モード分散（ｐｍｄ）を高い解像度で測定する方法およびｐｍｄ測定装置を較正する方法

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
US08/445,320 US5654793A (en) 1995-05-19 1995-05-19 Method and apparatus for high resolution measurement of very low levels of polarization mode dispersion (PMD) in single mode optical fibers and for calibration of PMD measuring instruments
US08/445,320 1995-05-19
US61733796A 1996-03-18 1996-03-18
US08/617,337 1996-03-18

Publications (1)

Publication Number Publication Date
WO1996036859A1 true WO1996036859A1 (fr) 1996-11-21

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JP (1) JP2000510573A (fr)
KR (1) KR19990014935A (fr)
CN (1) CN1196793A (fr)
AU (1) AU6022896A (fr)
CA (1) CA2219286A1 (fr)
WO (1) WO1996036859A1 (fr)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2310281A (en) * 1996-02-16 1997-08-20 Univ Geneve Method and device for measuring polarization dispersion of an optical fiber
DE19724676A1 (de) * 1997-06-11 1999-01-07 Siemens Ag Meßanordnung und Verfahren zur Bestimmung der Polarisationsmodendispersion von optischen Elementen
EP0863626A3 (fr) * 1997-02-05 1999-12-08 Nortel Networks Corporation Système de transmission optique avec surveillance de la dispersion de modes de polarisation
WO2004005877A1 (fr) * 2002-07-05 2004-01-15 Telecom Italia S.P.A Procede, systeme et dispositif de mesure de la dispersion de polarisation de mode d'une fibre optique
CN104006950A (zh) * 2014-06-12 2014-08-27 天津大学 一种保偏光纤双折射色散测量方法

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2844354B1 (fr) * 2002-09-05 2005-09-30 Cit Alcatel Procede de reflectometrie a onde optique polarisee (potdr)
JP4781746B2 (ja) * 2005-04-14 2011-09-28 株式会社フジクラ 光ファイバの複屈折測定方法及び測定装置及び光ファイバの偏波モード分散測定方法
CN101325454B (zh) * 2008-07-30 2012-05-02 烽火通信科技股份有限公司 一种在光纤偏振模色散测试中降低不确定度的方法
CN102164003B (zh) * 2010-12-20 2014-04-09 武汉虹拓新技术有限责任公司 一种色散测量装置
CN102636337A (zh) * 2012-04-26 2012-08-15 江苏大学 一种测量光纤色散的方法
CN105337969A (zh) * 2015-10-19 2016-02-17 朱建龙 两个移动终端之间的安全通信方法

Citations (3)

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Publication number Priority date Publication date Assignee Title
US3445833A (en) * 1965-11-01 1969-05-20 Sperry Rand Corp Signal responsive apparatus with a polar azimuth vibrator
US4241997A (en) * 1978-12-11 1980-12-30 General Motors Corporation Laser spectrometer with frequency calibration
US4750833A (en) * 1985-12-03 1988-06-14 Princeton Applied Research Corp. Fiber optic dispersion method and apparatus

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3445833A (en) * 1965-11-01 1969-05-20 Sperry Rand Corp Signal responsive apparatus with a polar azimuth vibrator
US4241997A (en) * 1978-12-11 1980-12-30 General Motors Corporation Laser spectrometer with frequency calibration
US4750833A (en) * 1985-12-03 1988-06-14 Princeton Applied Research Corp. Fiber optic dispersion method and apparatus

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2310281A (en) * 1996-02-16 1997-08-20 Univ Geneve Method and device for measuring polarization dispersion of an optical fiber
GB2310281B (en) * 1996-02-16 1999-09-01 Univ Geneve Method and device for measuring polarization dispersion of an optical fiber
EP0863626A3 (fr) * 1997-02-05 1999-12-08 Nortel Networks Corporation Système de transmission optique avec surveillance de la dispersion de modes de polarisation
DE19724676A1 (de) * 1997-06-11 1999-01-07 Siemens Ag Meßanordnung und Verfahren zur Bestimmung der Polarisationsmodendispersion von optischen Elementen
WO2004005877A1 (fr) * 2002-07-05 2004-01-15 Telecom Italia S.P.A Procede, systeme et dispositif de mesure de la dispersion de polarisation de mode d'une fibre optique
US7349077B2 (en) 2002-07-05 2008-03-25 Telecom Italia S.P.A. Method and apparatus for measuring the polarization mode dispersion of an optical fiber
CN104006950A (zh) * 2014-06-12 2014-08-27 天津大学 一种保偏光纤双折射色散测量方法
CN104006950B (zh) * 2014-06-12 2016-06-08 天津大学 一种保偏光纤双折射色散测量方法

Also Published As

Publication number Publication date
AU6022896A (en) 1996-11-29
JP2000510573A (ja) 2000-08-15
CA2219286A1 (fr) 1996-11-21
KR19990014935A (ko) 1999-02-25
CN1196793A (zh) 1998-10-21

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