EP1203463A2 - Mise en forme spectrale dynamique pour applications avec fibres optiques - Google Patents

Mise en forme spectrale dynamique pour applications avec fibres optiques

Info

Publication number
EP1203463A2
EP1203463A2 EP00979122A EP00979122A EP1203463A2 EP 1203463 A2 EP1203463 A2 EP 1203463A2 EP 00979122 A EP00979122 A EP 00979122A EP 00979122 A EP00979122 A EP 00979122A EP 1203463 A2 EP1203463 A2 EP 1203463A2
Authority
EP
European Patent Office
Prior art keywords
wavelength
controllable
dispersive element
grating
fiber optic
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.)
Withdrawn
Application number
EP00979122A
Other languages
German (de)
English (en)
Inventor
Asif A. Godil
David M. Bloom
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.)
Lightconnect Inc
Original Assignee
Lightconnect Inc
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 US09/372,649 external-priority patent/US6169624B1/en
Priority claimed from US09/548,788 external-priority patent/US6501600B1/en
Priority claimed from US09/549,781 external-priority patent/US6826330B1/en
Application filed by Lightconnect Inc filed Critical Lightconnect Inc
Publication of EP1203463A2 publication Critical patent/EP1203463A2/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/10—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating
    • H01S3/10007—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating in optical amplifiers
    • H01S3/10023—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating in optical amplifiers by functional association of additional optical elements, e.g. filters, gratings, reflectors
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B26/00—Optical devices or arrangements for the control of light using movable or deformable optical elements
    • G02B26/08—Optical devices or arrangements for the control of light using movable or deformable optical elements for controlling the direction of light
    • G02B26/0808—Optical devices or arrangements for the control of light using movable or deformable optical elements for controlling the direction of light by means of one or more diffracting elements
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/24—Coupling light guides
    • G02B6/26—Optical coupling means
    • G02B6/264—Optical coupling means with optical elements between opposed fibre ends which perform a function other than beam splitting
    • G02B6/266—Optical coupling means with optical elements between opposed fibre ends which perform a function other than beam splitting the optical element being an attenuator
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/24—Coupling light guides
    • G02B6/26—Optical coupling means
    • G02B6/28—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals
    • G02B6/293—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means
    • G02B6/29304—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means operating by diffraction, e.g. grating
    • G02B6/29305—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means operating by diffraction, e.g. grating as bulk element, i.e. free space arrangement external to a light guide
    • G02B6/2931—Diffractive element operating in reflection
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/24—Coupling light guides
    • G02B6/26—Optical coupling means
    • G02B6/28—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals
    • G02B6/293—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means
    • G02B6/29304—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means operating by diffraction, e.g. grating
    • G02B6/29305—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means operating by diffraction, e.g. grating as bulk element, i.e. free space arrangement external to a light guide
    • G02B6/29313—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means operating by diffraction, e.g. grating as bulk element, i.e. free space arrangement external to a light guide characterised by means for controlling the position or direction of light incident to or leaving the diffractive element, e.g. for varying the wavelength response
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/24—Coupling light guides
    • G02B6/26—Optical coupling means
    • G02B6/28—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals
    • G02B6/293—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means
    • G02B6/29379—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means characterised by the function or use of the complete device
    • G02B6/29395—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means characterised by the function or use of the complete device configurable, e.g. tunable or reconfigurable
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/24—Coupling light guides
    • G02B6/26—Optical coupling means
    • G02B6/27—Optical coupling means with polarisation selective and adjusting means
    • G02B6/2753—Optical coupling means with polarisation selective and adjusting means characterised by their function or use, i.e. of the complete device
    • G02B6/2793—Controlling polarisation dependent loss, e.g. polarisation insensitivity, reducing the change in polarisation degree of the output light even if the input polarisation state fluctuates
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S2301/00—Functional characteristics
    • H01S2301/04—Gain spectral shaping, flattening
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/05—Construction or shape of optical resonators; Accommodation of active medium therein; Shape of active medium
    • H01S3/06—Construction or shape of active medium
    • H01S3/063—Waveguide lasers, i.e. whereby the dimensions of the waveguide are of the order of the light wavelength
    • H01S3/067—Fibre lasers
    • H01S3/06754—Fibre amplifiers
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00—Semiconductor lasers
    • H01S5/005—Optical components external to the laser cavity, specially adapted therefor, e.g. for homogenisation or merging of the beams or for manipulating laser pulses, e.g. pulse shaping

Definitions

  • the present invention relates to dynamically shaping the spectral response with high resolution for fiber-optic applications. More particularly, the present invention relates to dynamic gain or channel equalization for erbium doped fiber amplifiers (EDFA) used in WDM networks.
  • EDFA erbium doped fiber amplifiers
  • the EDFA gain is highly non-uniform across the EDFA spectral band. Therefore gain flattening is an important part of good EDFA design and operation. Presently this is accomplished using a static gain flattening filter based on thin film filter technology or more recently on fiber bragg gratings. The dynamic aspect is covered by using a variable optical attenuator between the two stages of an EDFA.
  • An object of the present invention is to provide controllable transmission in a communications system.
  • Another object of the present invention is to provide controllable transmission in a communications system as a function of wavelength.
  • a further object of the present invention is to provide controllable compensation for the wavelength dependent gain of EDFA' s.
  • Yet another object of the present invention is to provide controllable and dynamic compensation for the dynamic wavelength dependent gain of EDFA' s.
  • an optical system includes an EDFA system with at least one amplifier stage.
  • a spectral shaping device is coupled to the EDFA system.
  • the spectral shaping device includes a fiber optic input port that provides an input beam.
  • a wavelength dispersive element is coupled to the input port. The wavelength dispersive element spreads the input beam in at least one dimension as a function of wavelength and generates a dispersed beam.
  • a controllable grating reflects the dispersed beam to the wavelength dispersive element and generates a recombined beam. The controllable grating provides a controllable reflectivity as a function of wavelength.
  • a fiber optic output port is positioned to receive the recombined beam.
  • the optical system provides a desired controllable wavelength flatness.
  • an optical system includes a fiber optic input port providing an input beam and a wavelength dispersive element coupled to the input port.
  • the wavelength dispersive element spreads the input beam in at least one dimension as a function of wavelength and generates a dispersed beam.
  • a controllable grating reflects the dispersed beam to the wavelength dispersive element and generates a recombined beam.
  • the controllable grating provides a controllable reflectivity as a function of wavelength.
  • a fiber optic output port is positioned to receive the recombined beam.
  • An EDFA is coupled to the fiber optic input port.
  • the optical system provides a desired controllable wavelength flatness.
  • Figure 1(a) is a schematic top view of one embodiment of an optical system of the present invention that is utilized for dynamic spectral shaping.
  • Figure 1(b) is a schematic side view of the Figure 1(a) optical system.
  • Figure 2(a) is a schematic top view of a deformable grating, modulator array utilized in one embodiment of the present invention.
  • Figure 2(b) is a schematic side view of the Figure 2(a) deformable grating, modulator array.
  • Figure 3(a) is a schematic top view of a modified Figure 1(a) optical system that includes a circulator to extract the output light.
  • Figure 3(b) is a schematic side view of the Figure 3(a) optical system with circulator.
  • Figure 4(a) is a schematic top view of a modified Figure 1(a) optical system that includes of a quarter- wave plate to minimize PDL.
  • Figure 4(b) is a schematic side view of the Figure 4(a) optical system.
  • Figure 5 is a schematic top view of one embodiment of an optical system of the present invention that is utilized for dynamic spectral shaping and incorporates an array waveguide grating.
  • FIGURE 1 illustrates one embodiment of an optical system 100 of the present invention for the dynamic spectral shaping. Its comprised of an input optical fiber 105, an output optical fiber 115, an input collimating lens 110 of focal length fl, an output collimating lens 120 of focal length fl, a walkoff birefringent plate 130 on the input side, a walkoff birefringent plate 135 on the output side, a half wave plate 140, a grating 150 to diffract the light onto a focusing lens 160 of focal length f2, and then onto the device array 200.
  • an input optical fiber 105 comprised of an input optical fiber 105, an output optical fiber 115, an input collimating lens 110 of focal length fl, an output collimating lens 120 of focal length fl, a walkoff birefringent plate 130 on the input side, a walkoff birefringent plate 135 on the output side, a half wave plate 140, a grating 150 to diffract the light onto a focusing
  • the broadband light from the input optical fiber 105 is collimated by lens 110 which may be a GRIN lens, spherical lens or any other suitable lens.
  • lens 110 which may be a GRIN lens, spherical lens or any other suitable lens.
  • the collimated light passes through a walkoff birefringent plate 130 such as YVO4, calcite or LiNbO3.
  • the ordinary polarization goes straight through while the extraordinary polarization is displaced downwards by an amount, which if designed properly, should be greater than the beam size.
  • the polarization of one of the displaced beams is rotated by using a half wave plate (HWP) 140 and made the same as the other beam. Now both beams are either vertically or horizontally polarized.
  • HWP half wave plate
  • the polarization direction is chosen to maximize the diffraction efficiency of the grating 150 which may be a holographic grating or a blazed grating.
  • Two parallel beams impinge on the grating which diffracts the light towards the upper half of a focusing lens 160 of focal length f2 which is placed a distance f2 away from the grating.
  • This telecentric use walks the focused beam across the device array 200 as a function of wavelength.
  • the two polarization paths come together on the device array which is segmented to cover different spectral slices.
  • the reflected light from the device goes through the bottom half of the lens 160 and impinges on the grating which puts all the wavelengths back to gather.
  • the polarization is combined again using the HWP and the output birefringent plate 135 which is oriented opposite from the input birefringent plate.
  • the beam is focused into the output fiber 115 using another collimating lens 120.
  • the device array 200 may be an array of LCD elements, a suitable MEMS device array such as micro mirrors or cantilevers, an array of electro- optic modulators, an array of acousto-optic modulators or any light controlling device array.
  • the preferred embodiment is based on using a deformable grating modulator array invented by Bloom et. al. (patent no. 5,311,360) as shown in FIG. 2A,B.
  • the device is comprised of ribbons 199 of width w suspended above the substrate 198.
  • the top surface of the ribbon is a height d above the substrate. Ribbons are electrically connected and driven in pairs. Each pair controls a spectral slice.
  • 201 controls ⁇ l
  • 202 controls ⁇ 2, and so on till 20n controls ⁇ n.
  • the gap between the ribbons is also w. All ribbons and gaps are covered with a reflective layer which may be aluminum or gold.
  • a reflective layer which may be aluminum or gold.
  • d m ⁇ l/2.
  • d 2362 nm.
  • the shorter wavelength elements will start out with the ribbons already slightly pulled in.
  • the spectral resolution of the system is determined by fl, f2, grating pitch and the grating incident angle. The resolution should be such that going from ⁇ l to ⁇ 2 moves the spot across the device array by w.
  • An alternate embodiment of the optical system 300 is shown in FIG. 3A,B, which is the same as system 100 in FIG. 1, except a circulator 103 is used to separate out the light in the input fiber 101 from the output fiber 102.
  • FIG. 400 Yet another embodiment of the optical system 400 is shown in FIG.
  • dispersive element 150 is an arrayed waveguide grading ("AWG").
  • a suitable AWG 150 is manufactured by Lightwave Microsystems, San Jose, California.
  • device array 200 which can be a controllable, deformable grating modulator, can be placed in close proximity to the dispersed output at AWG 150. This proximity is selected to provide good coupling efficiency back into the waveguides of AWG 150.
  • the maximum distance depends on the size of the waveguides of AWG 150. In a preferred embodiment, the distance is 10 microns or less and can be butt-coupled.
  • AWG 150 disperses the light from the input optical fiber 105 and spreads the input beam in at least one dimension as a function of wavelength where it impinges on device array 200.
  • the spatially dispersed light is reflected back into AWG 150 which subsequently recombines the light into optical fiber 105 but in a counterpropagating direction to the input.
  • the output light can be extracted by circulator 103.
  • Other embodiments can include a separate output port and do not require the circulator.

Landscapes

  • Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • General Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Engineering & Computer Science (AREA)
  • Plasma & Fusion (AREA)
  • Optical Couplings Of Light Guides (AREA)
  • Mechanical Light Control Or Optical Switches (AREA)
  • Optical Modulation, Optical Deflection, Nonlinear Optics, Optical Demodulation, Optical Logic Elements (AREA)
  • Light Guides In General And Applications Therefor (AREA)

Abstract

La présente invention concerne la mise en forme spectrale dynamique. A l'aide d'un réseau gravé, la bande spectrale est étalée à travers un ensemble de systèmes mécaniques microélectriques ou tout autre système matriciel approprié. Le dispositif peut être le modulateur de réseau gravé déformable inventé par Bloom et. al. (Brevet d'invention no 5. 311. 360) ou tout autre dispositif approprié. Cette invention concerne également le couplage en entrée et en sortie de la fibre et peut utiliser la polarisation optique pour veiller à ce que le réseau gravé ne soit utilisé que dans une seule polarisation où l'efficacité de diffraction est supérieure.
EP00979122A 1999-08-11 2000-08-08 Mise en forme spectrale dynamique pour applications avec fibres optiques Withdrawn EP1203463A2 (fr)

Applications Claiming Priority (11)

Application Number Priority Date Filing Date Title
US548788 1990-07-06
US549781 1990-07-09
US37271299A 1999-08-11 1999-08-11
US09/372,649 US6169624B1 (en) 1999-08-11 1999-08-11 Achromatic optical modulators
US372649 1999-08-11
US372712 1999-08-11
US17168599P 1999-12-21 1999-12-21
US171685P 1999-12-21
US09/548,788 US6501600B1 (en) 1999-08-11 2000-04-13 Polarization independent grating modulator
US09/549,781 US6826330B1 (en) 1999-08-11 2000-04-14 Dynamic spectral shaping for fiber-optic application
PCT/US2000/021662 WO2001011419A2 (fr) 1999-08-11 2000-08-08 Mise en forme spectrale dynamique pour applications avec fibres optiques

Publications (1)

Publication Number Publication Date
EP1203463A2 true EP1203463A2 (fr) 2002-05-08

Family

ID=27538845

Family Applications (1)

Application Number Title Priority Date Filing Date
EP00979122A Withdrawn EP1203463A2 (fr) 1999-08-11 2000-08-08 Mise en forme spectrale dynamique pour applications avec fibres optiques

Country Status (4)

Country Link
EP (1) EP1203463A2 (fr)
JP (1) JP2003506988A (fr)
AU (1) AU1653701A (fr)
WO (1) WO2001011419A2 (fr)

Families Citing this family (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6724125B2 (en) 1999-03-30 2004-04-20 Massachusetts Institute Of Technology Methods and apparatus for diffractive optical processing using an actuatable structure
WO2002075410A1 (fr) * 2001-03-19 2002-09-26 Capella Photonics, Inc. Multiplexeurs d'insertion-extraction optiques reconfigurables
US7126740B2 (en) 2001-04-03 2006-10-24 Cidra Corporation Multifunctional optical device having a spatial light modulator with an array of micromirrors
WO2002082166A2 (fr) * 2001-04-03 2002-10-17 Cidra Corporation Source optique variable
WO2002082165A2 (fr) * 2001-04-03 2002-10-17 Cidra Corporation Filtre optique dynamique a modulateur spatial de lumiere
CN1511271A (zh) * 2001-04-13 2004-07-07 康宁股份有限公司 应用于电信的高对比度液晶显示器
WO2003017537A1 (fr) * 2001-08-16 2003-02-27 Telefonaktiebolaget Lm Ericsson (Publ) Amplificateur optique
US7046410B2 (en) 2001-10-11 2006-05-16 Polychromix, Inc. Actuatable diffractive optical processor
US20030133186A1 (en) * 2002-01-15 2003-07-17 Yakov Reznichenko Optical switching system and apparatus with integral covering lens
AU2003207732A1 (en) * 2002-01-28 2003-09-02 Cidra Corporation Multifunctional optical device having a spatial light modulator with an array of micromirrors
GB0205794D0 (en) 2002-03-12 2002-04-24 Montelius Lars G Mems devices on a nanometer scale
US6985308B1 (en) 2002-05-28 2006-01-10 Polychromix Corporation Telecommunications optical processor
AU2002950003A0 (en) * 2002-07-05 2002-09-12 Edith Cowan University A multi-function opto-vlsi processor for intelligent optial networks
US6842556B2 (en) 2002-09-10 2005-01-11 Analog Devices, Inc. Two input, two output optical switch using two movable mirrors
NO20033940D0 (no) * 2003-09-05 2003-09-05 Photonyx As Fremgangsmåte og innretning for reduksjon av polariseringsavhengige effekter i en styrbar optisk komponent
US20070194239A1 (en) 2006-01-31 2007-08-23 Mcallister Abraham Apparatus and method providing a hand-held spectrometer
JP5228205B2 (ja) 2007-06-15 2013-07-03 独立行政法人情報通信研究機構 光波形整形装置

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH05224158A (ja) * 1992-02-14 1993-09-03 Matsushita Electric Ind Co Ltd 光フィルター及びその光フィルターを用いた光増幅装置
US5311360A (en) * 1992-04-28 1994-05-10 The Board Of Trustees Of The Leland Stanford, Junior University Method and apparatus for modulating a light beam
US5526155A (en) * 1993-11-12 1996-06-11 At&T Corp. High-density optical wavelength division multiplexing
US5793912A (en) * 1994-06-09 1998-08-11 Apa Optics, Inc. Tunable receiver for a wavelength division multiplexing optical apparatus and method
JP3883601B2 (ja) * 1996-03-27 2007-02-21 富士通株式会社 光イコライザ
US5745271A (en) * 1996-07-31 1998-04-28 Lucent Technologies, Inc. Attenuation device for wavelength multiplexed optical fiber communications
US5960133A (en) * 1998-01-27 1999-09-28 Tellium, Inc. Wavelength-selective optical add/drop using tilting micro-mirrors
US5943158A (en) * 1998-05-05 1999-08-24 Lucent Technologies Inc. Micro-mechanical, anti-reflection, switched optical modulator array and fabrication method

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO0111419A2 *

Also Published As

Publication number Publication date
WO2001011419A2 (fr) 2001-02-15
AU1653701A (en) 2001-03-05
WO2001011419A9 (fr) 2002-07-18
WO2001011419A3 (fr) 2001-09-13
JP2003506988A (ja) 2003-02-18

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