CN106569357B - A kind of multiple degrees of freedom spectral filter can compensate for polarization mode dispersion - Google Patents
A kind of multiple degrees of freedom spectral filter can compensate for polarization mode dispersion Download PDFInfo
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- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells
- G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
- G02F1/13306—Circuit arrangements or driving methods for the control of single liquid crystal cells
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- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells
- G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
- G02F1/1333—Constructional arrangements; Manufacturing methods
- G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
- G02F1/133528—Polarisers
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- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells
- G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
- G02F1/1333—Constructional arrangements; Manufacturing methods
- G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
- G02F1/13363—Birefringent elements, e.g. for optical compensation
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells
- G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
- G02F1/1333—Constructional arrangements; Manufacturing methods
- G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
- G02F1/133528—Polarisers
- G02F1/133531—Polarisers characterised by the arrangement of polariser or analyser axes
Abstract
The present invention is a kind of multiple degrees of freedom spectral filter that can compensate for polarization mode dispersion, including the first optical fiber collimator, film polarizer, phase type liquid crystal, the second optical fiber collimator, additional polarization maintaining optical fibre, the polarization maintaining optical fibre of optical axis rotation and optical fiber analyzer.It by rotating thin film polarizing film, adjusts phase type liquid crystal voltage and adjusts the length of additional polarization maintaining optical fibre, can realize that the decoupling of the modulation depth to filter, peak wavelength and Free Spectral Range is adjusted respectively, there is high controllability.This device can be used for compensating in high power laser system wide spectrum optical when transmitting in polarization-maintaining device and polarization maintaining optical fibre, the amplitude-frequency mudulation effect introduced due to optic fiber polarization mould dispersion.In use, the time domain waveform that this device can be monitored according to oscillograph, adjusts compensation device parameter by computer feedback control controller, realizes the automatic real-time compensation to optic fiber polarization mould dispersion.
Description
Technical field
The present invention relates to spectral filtering device field, specifically a kind of multiple degrees of freedom spectrum filter that can compensate for polarization mode dispersion
Wave device.
Background technique
In laser field, especially high power laser light field, in order to control the generation of nonlinear effect and to realize coke
The even cunning of spot and the Smoothing by Spectral Dispersion technology used, need that single-frequency laser is carried out video stretching using phase-modulator.However,
Polarization mode dispersion present in polarization-maintaining device and polarization maintaining optical fibre in laser system is (including Differential Group Delay and low polarization extinction
Than), polarization filtering effect can be generated, so that spectral component transmissivity different in the spectrum after broadening is uneven, is reached
When output end, the frequency modulating section that will lead to laser is converted to amplitude modulation, and this phenomenon is referred to as in superpower laser
Amplitude-frequency mudulation effect.Amplitude-frequency modulation not only results in photosignal waveform distortion, more seriously will increase the damage of optical element
Cold danger and the validity for reducing Physical Experiment.It is therefore desirable to compensate to it.In high power laser system, polarization mode
Influence of the dispersion to pulse changes at random at any time.This is because when light pulse is transmitted in polarization maintaining optical fibre, when polarization-maintaining light
Fine surrounding environment change (temperature change or by ambient pressure), can generate complicated and random influence, this meeting to transmission pulse
Cause the amplitude-frequency of reproduced pulse to be modulated and also show as time-varying characteristics, therefore is difficult to compensate it.In addition, according to high power
Laser system tests the difference of demand, and the length of polarization maintaining optical fibre can also adjust therewith in front end system, this will lead to polarization filtering
The free spectral range for the filter function that effect generates generates variation, so that the influence to light pulse changes.
Current existing Polarization Mode Dispersion Compensation mainly uses different types of Polarization Controller, such as: two/
Combination, liquid crystal of one wave plate and quarter-wave plate etc..But the combination flexible adjustment of half wave plate and quarter-wave plate
Spend lower, free spectral range not malleable；And liquid crystal system control system is complex, and needs special according to use demand
Design and produce liquid crystal device, higher cost.Another effectively compensation way is to revolve two sections of isometric polarization maintaining optical fibre optical axises
Welding after turning 90 °, although the Differential Group Delay of this method energy compensated optical fiber, can not compensate influence caused by random phase shift,
And flexibility ratio is not high.The peak wavelength and modulation depth that mainly can cause system filter function in view of polarization mode dispersion are at any time
Between change；And polarization maintaining optical fibre length used in laser system is different, and will cause the Free Spectral Range of its filter function
Change.Therefore, design it is a set of can the multiple degrees of freedom Polarization Mode Dispersion Compensation Systems of automatic adjusument be necessary.
Summary of the invention
Present invention aims to overcome that above-mentioned the deficiencies in the prior art, provide it is a kind of can compensate for polarization mode dispersion mostly freely
Spectral filter is spent, for solving existing polarization film dispersion compensating device free spectral range adjustment difficulty, adaptive control system
Complicated problem.Specifically, the object of the present invention is to provide a kind of multiple degrees of freedom spectral filter, peak wavelength, modulation
Depth and Free Spectral Range can be adjusted as needed.Invention further aims to provide a devcie and method, described
Method can be by providing the closed-loop control available multiple degrees of freedom spectral filter of one kind to the polarization in polarizer and polarization maintaining optical fibre
Mode dispersion carries out real-time compensation, can carry out real-time feedback control to the compensation device by monitoring pulse temporal waveform, with
Amplitude-frequency mudulation effect caused by polarization mode dispersion in inhibition system.
The technology used in the present invention is as follows:
A kind of multiple degrees of freedom spectral filter can compensate for polarization mode dispersion, including the first optical fiber collimator, it is mounted on rotation
Turn the film polarizer on adjustment frame, the phase type liquid crystal equipped with liquid-crystal controller, the second optical fiber collimator, additional polarization-maintaining light
The fine, polarization maintaining optical fibre of optical axis rotation and optical fiber analyzer；The tail optical fiber of first optical fiber collimator is connect with input optical fibre, through
Light after the collimation output of one optical fiber collimator becomes linearly polarized light after the film polarizer, inclined by rotating the film
Shake piece, and the liquid crystal optic axis of the polarization direction for making the linearly polarized light and the phase type liquid crystal is incident on phase type at an angle
It is parallel and vertical with liquid crystal optic axis direction after the phase type liquid crystal by liquid-crystal controller load alternating voltage on liquid crystal
Two polarized components generate certain phase delay, then through the second optical fiber collimator coupled into optical fibres, the tail of the second optical fiber collimator
Fine to connect with additional polarization maintaining optical fibre, the polarization maintaining optical fibre of the another port and optical axis rotation that add polarization maintaining optical fibre connects, optical axis rotation
The output end of polarization maintaining optical fibre be connected with the input terminal of optical fiber analyzer, after the analyzing of optical fiber analyzer, from optical fiber analyzer
Output end export and enter output optical fibre and continue to transmit.
By rotating the film polarizer, the voltage of the phase type liquid crystal and the length of the additional polarization maintaining optical fibre are adjusted
Degree can realize that the decoupling of the modulation depth to filter, peak wavelength and Free Spectral Range is adjusted respectively.
The tail optical fiber of second optical fiber collimator need to use polarization maintaining optical fibre.
The normal direction of the film polarizer is parallel with direction of beam propagation.
The length of the additional polarization maintaining optical fibre is selected according to actual needs.
The polarization maintaining optical fibre of the optical axis rotation is selected as 45 ° most preferably to shaft angle degree.
The liquid-crystal controller and the rotation adjustment frame are connected with computer respectively, which is connected with oscillograph,
To realize the real-time compensation to polarization mode dispersion, to realize the Remote closed loop control modulated to pulse amplitude-frequency.
The features and advantages of the invention:
The present invention overcomes existing compensation method adjust freedom degree it is few, the complex disadvantage of control system is, it can be achieved that right
The decoupling of filter peak wavelength, modulation depth and Free Spectral Range is adjusted, and has the characteristic compatible with fibre system.
Wherein, the tuning of peak wavelength is identical as the voltage transformation qualitative tendency of liquid crystal phase, and the variation of modulation depth and wave plate rotate
Angle is in simple parabolic relation, therefore the highly controllable adjusting easy to accomplish to filter.Due to its high controllability and
Flexibility, the multiple degrees of freedom spectral filter can be used for being drawn in device of high power laser by polarizer and polarization maintaining optical fibre
The polarization mode dispersion risen carries out real-time compensation, can carry out Real-time Feedback to the compensation device by monitoring pulse temporal waveform
Control, thus amplitude-frequency mudulation effect caused by polarization mode dispersion in inhibition system.
Detailed description of the invention
Fig. 1 is the structural schematic diagram for the multiple degrees of freedom spectral filter that the present invention can compensate for polarization mode dispersion.
In figure, the first optical fiber collimator of 1-, 2- film polarizer, 3- phase type liquid crystal, the second optical fiber collimator of 4-, 5- are attached
Add polarization maintaining optical fibre, the polarization maintaining optical fibre of 6- optical axis rotation, 7- optical fiber analyzer.
Fig. 2 is the variation schematic diagram that filters modulate depth rotates angle with film polarizer.Fig. 2 (a) is filter function
The variation rotated with film polarizer；Fig. 2 (b) is the relation curve that modulation depth and film polarizer rotate angle.
Fig. 3 is variation schematic diagram of the filter peak wavelength with liquid crystal voltage.Fig. 3 (a) is peak wavelength and peak power
Change curve；Fig. 3 (b) is liquid crystal retardation performance with alive change curve.
Fig. 4 is the variation schematic diagram that filter Free Spectral Range changes with additional polarization maintaining optical fibre length.Fig. 4 (a) is attached
Adding polarization maintaining optical fibre length is 0m；Fig. 4 (b) is that additional polarization maintaining optical fibre length is 1.5m；Fig. 4 (c) is that additional polarization maintaining optical fibre length is
3m；Fig. 4 (d) is that additional polarization maintaining optical fibre length is 5m.
Fig. 5 is the structural representation of another embodiment for the multiple degrees of freedom spectral filter that the present invention can compensate for polarization mode dispersion
Figure.In figure, 8- computer, 9- oscillograph.
Fig. 6 is that the effect compensated is modulated to amplitude-frequency caused by high power laser system polarization mode dispersion using the filter
Fruit figure.Light pulse signal when Fig. 6 (a) is not compensated for oscillograph is collected；Fig. 6 (b) is that oscillograph is collected by this
Light pulse signal after the compensation device of invention；Fig. 6 (c) is that pulse in 3 hours after automatic feedback compensation is carried out using the present invention
The situation of change of amplitude-frequency modulation.
Specific embodiment
It is described in further detail with reference to the accompanying drawing with example.
Embodiment 1: as shown in Fig. 1, a kind of multiple degrees of freedom spectral filter can compensate for polarization mode dispersion, including center
Optical fiber collimator 1, the transmission peak wavelength of wavelength 1053nm is the film polarizer 2 of 550~1500nm, clear aperatureThoroughly
The half-wave phase type liquid crystal 3 of a length of 1050~1700nm of ejected wave, the second optical fiber collimator 4 that tail optical fiber is 1053nm polarization maintaining optical fibre,
Additional polarization maintaining optical fibre 5 that transmission wavelength is 1053nm, polarization maintaining optical fibre 6, the tail optical fiber of welding are 1053nm polarization-maintaining after 45 ° of optical axis rotation
The optical fiber analyzer 7 of optical fiber.
When not considering the group velocity dispersion and loss of optical fiber introducing, the system filter function of the filter can use Jones
Matrix is expressed as
Hout(f)=MILP·MCON·MPM-R-PM·MCON·MPM·MLC·MP·Hin(f),
H in formulainIt (f) is input light spectral function, MPFor film polarizer transmission matrix, MLCFor liquid crystal transmission matrix, MPM
To add polarization maintaining optical fibre transmission matrix, MCONFor flange transmission matrix, MPM-R-PMFor 45 ° of polarization maintaining optical fibre transmission matrixs of shaft, MILP
For the transmission matrix of optical fiber analyzer.The transmission matrix form of each optical element is as follows:ρ
For the angle of line polarisation polarization direction and liquid crystal optic axis after the polarizer；
η is that liquid crystal damages the opposite polarization that slow axial light (it is lossless to set fast axle) introduces
Consumption,The relative phase shift that the optical signal that slow axis transmits is introduced for liquid crystal (relative to fast axle)；
L is polarization maintaining optical fibre length, and ε is polarization maintaining optical fibre polarization mode dispersion constant, usual polarization-maintaining
Optical fiber is 1.5~2ps/m,The random phase shift introduced for polarization maintaining optical fibre；
θcIt is related with flange extinction ratio；
l1,l2Respectively turn
Two sections of polarization maintaining optical fibre length of axis docking；
l3For film polarizer injection end polarization maintaining optical fibre length.
Use the fluorescence source that spectrum width is 40nm as injection light, the light through the collimation output of the first optical fiber collimator is through described thin
After film polarizing film, become linearly polarized light, the line polarisation polarization direction and liquid crystal optic axis are incident on phase type liquid crystal at an angle
On, after the phase type liquid crystal for being added alternating voltage, two polarized components parallel and vertical with liquid crystal optic axis direction generate certain
Phase delay, then through the second optical fiber collimator coupled into optical fibres, the tail optical fiber of the second optical fiber collimator is connect with additional polarization maintaining optical fibre,
The another port of additional polarization maintaining optical fibre and the polarization maintaining optical fibre of optical axis rotation connect, the output end and light of the polarization maintaining optical fibre of optical axis rotation
The input terminal of fine analyzer is connected, and after the analyzing of optical fiber analyzer, exports from the output end of optical fiber analyzer and enters output
Optical fiber continues to transmit.
The modulation depth for investigating filter decouples tuning capability.Voltage is not added in liquid crystal, and adding polarization maintaining optical fibre length is 3m.If
It sets film polarizer adjustment frame initial angle and is directed at 1 ° of graduation mark, then rotate adjustment frame counterclockwise to 15 ° for step-length with 1 °, filter
Device modulation depth is as shown in Fig. 2 with the variation of film polarizer rotation angle.As seen from the figure, in adjusting, filter peak
Wavelength and Free Spectral Range have almost no change, and illustrate the decoupling tuning for realizing modulation depth.Fig. 2 (a) is filter function
With the change curve that film polarizer rotates, the variation for modulation depth that solid line is corresponding when turning to 11 ° by 1 °, dotted line it is corresponding by
The variation of 12 ° of modulation depths when turning to 15 °.The situation of corresponding modulating depth maximum at 1 °, with the rotation of polarizing film, modulation
Depth gradually lowers, and modulation depth is minimum when rotation is to 11 °, continues to rotate at this time, by dotted line as it can be seen that modulation depth is again with rotation
The increase of gyration and increase.Fig. 2 (b) is to rotate modulation depth and film polarizer when angle is 1 ° to 11 ° to rotate angle
Relation curve is approximately parabolic type.
Embodiment 2: the peak wavelength decoupling tuning capability of filter is investigated.Implementation condition is same as Example 1, but keeps
Film polarizer angle is constant, and adding polarization maintaining optical fibre length is 3m.It is gradually increased to voltage value added by liquid crystal, obtains filter
Peak wavelength and peak power are as shown in Fig. 3 with the variation schematic diagram of liquid crystal voltage.As seen from the figure, in adjusting, filter
Peak power has almost no change, and illustrates that modulation depth does not change with liquid crystal voltage, namely realizes the decoupling tune of peak wavelength
It is humorous.Fig. 3 (a) is peak wavelength and the change curve that peak power is pressurizeed with liquid crystal；Fig. 3 (b) is liquid crystal retardation performance with added
The change curve of voltage.Two curves are compared as it can be seen that the tuning of peak wavelength and the voltage transformation characteristic of liquid crystal phase are completely corresponding,
Therefore high duplication is carried out to peak wavelength with can be convenient, height is controllably adjusted.Further, since being used in this system
Half-wave liquid crystal phase retardation device, therefore tunable wavelength range is 0.8nm, if using the higher liquid crystal of phase delay ability, it can
Tuning range can further increase.
Embodiment 3: the situation of change that filter Free Spectral Range changes with additional polarization maintaining optical fibre length is investigated.Implement item
Part is same as Example 1, but keeps voltage value added by film polarizer angle and liquid crystal constant, replaces different additional polarization-maintainings
It is as shown in Fig. 4 with the variation schematic diagram of liquid crystal voltage to obtain filter peak wavelength and peak power for fiber lengths.Required
Additional polarization maintaining optical fibre length can be calculated according to required Free Spectral Range according to formula: the ε l of Δ ν=1/, and free light
Transformational relation meets when spectral limit frequency and wavelength are stated:In use, it is noted that the l in formula is
Second collimator tail optical fiber, additional the sum of polarization maintaining optical fibre and the total length of shaft polarization maintaining optical fibre front half section optical fiber.Fig. 4 (a) is additional
The case where polarization maintaining optical fibre length is 0m, corresponding Free Spectral Range are 1.6nm；Fig. 4 (b) is that additional polarization maintaining optical fibre length is 1.5m
The case where, corresponding Free Spectral Range is 0.7nm；Fig. 4 (c) is the case where additional polarization maintaining optical fibre length is 3m, corresponding free light
Spectral limit is 0.55nm；Fig. 4 (d) is the case where additional polarization maintaining optical fibre length is 5m, and corresponding Free Spectral Range is 0.36nm.It is right
Polarization maintaining optical fibre used in embodiment, polarization mode dispersion constant is 1.6ps/m, and the second collimator tail optical fiber is 1m, is turned
Axis polarization maintaining optical fibre front half section fiber lengths are 0.5m, therefore are 0,1.5,3m by the additional polarization maintaining optical fibre length that arrives that formula calculates
When with 5m, Free Spectral Range is respectively 1.54,0.76,0.51nm and0.36nm, and is consistent in this example.
Embodiment 4: it is directed to central wavelength 1053.1020nm, broadening amount is the wide spectrum optical of 0.38nm, by high power laser light
The low extinction ratio polarization maintaining optical fibre section output of polarizer (inside having birefringece crystal), multistage in front end system, then by 10m polarization maintaining optical fibre
After transmission, filter of the present invention is accessed, the liquid crystal control of film polarizer adjustment frame and phase type liquid crystal in filter
Device processed is connected with computer, is automatically controlled with realizing, and another interface of computer is connected with oscillograph, to receive oscillograph acquisition
The structural schematic diagram of real-time pulse waveform, the embodiment is as shown in Figure 5.Fig. 6 is using the filter to high power laser system
Amplitude-frequency caused by polarization mode dispersion modulates the effect picture compensated.For the size for measuring amplitude-frequency modulation voltage, Chang Dingyi waveform is turned round
Qu YinziPmaxAnd PminThe minimum and maximum crest voltage of pulse respectively on oscillograph.Fig. 6 (a) is
The light pulse signal that oscillograph is collected when not compensating, it is seen that serious amplitude-frequency modulation, α ≈ occurs in waveform flat-top area
18%, due to the uncertain influence of external environment, which can change with the time, and α can be changed to super by 2%
Cross 20%；Fig. 6 (b) is the collected light pulse signal after compensation device of the invention of oscillograph, it is seen that amplitude-frequency modulation
Amount can be compensated to the magnitude of very little, α ≈ 3.2%, and pulse top is close to flat-top；Fig. 6 (c) is automatic anti-using present invention progress
The situation of change that pulse amplitude-frequency is modulated in 3 hours after feedback compensation carries out automatic feedback through device of the present invention as seen from the figure
After compensation, the amplitude-frequency modulation voltage of pulse is controlled within 2~6.5%.
The foregoing is only a preferred embodiment of the present invention, is not intended to restrict the invention；For the skill of this field
For art personnel, the invention may be variously modified and varied.All within the spirits and principles of the present invention, made any to repair
Change, equivalent replacement, improvement etc., should all be included in the protection scope of the present invention.
Claims (6)
1. a kind of multiple degrees of freedom spectral filter that can compensate for polarization mode dispersion, including the first optical fiber collimator (1), it is mounted on rotation
Turn film polarizer (2) on adjustment frame, the polarization maintaining optical fibre (6) of optical axis rotation and the phase type liquid equipped with liquid-crystal controller
Brilliant (3), the second optical fiber collimator (4), additional polarization maintaining optical fibre (5) and optical fiber analyzer (7)；It is characterized by: the phase type
The optical axis of liquid crystal (3) is parallel with the tail optical fiber optical axis of the second optical fiber collimator (4), the tail optical fiber of first optical fiber collimator (1) with
Input optical fibre connection, the light after the output of the first optical fiber collimator (1) collimation become linearly polarized light through the film polarizer (2)
Afterwards, it is incident on the phase type liquid crystal (3), after the phase type liquid crystal (3) by liquid-crystal controller load alternating voltage, then
Through the second optical fiber collimator (4) coupled into optical fibres, the tail optical fiber of second optical fiber collimator (4) is defeated with additional polarization maintaining optical fibre (5)
Enter end connection, the output end of additional polarization maintaining optical fibre (5) is connect with the input terminal of the polarization maintaining optical fibre (6), the polarization maintaining optical fibre (6)
Output end be connected with the input terminal of optical fiber analyzer (7), after the analyzing of optical fiber analyzer (7), from optical fiber analyzer (7)
Output end, which exports and enters output optical fibre, to be continued to transmit；
By rotating the film polarizer (2), the voltage and the additional polarization maintaining optical fibre of the phase type liquid crystal (3) are adjusted
(5) length realizes that the decoupling of the modulation depth to filter, peak wavelength and Free Spectral Range is adjusted respectively；Pass through rotation
Turn the film polarizer (2), the liquid crystal optic axis of the polarization direction and the phase type liquid crystal (3) that make the linearly polarized light is in one
Determine angle incidence.
2. a kind of multiple degrees of freedom spectral filter that can compensate for polarization mode dispersion according to claim 1, it is characterised in that:
The tail optical fiber of second optical fiber collimator (4) uses polarization maintaining optical fibre.
3. a kind of multiple degrees of freedom spectral filter that can compensate for polarization mode dispersion according to claim 1, it is characterised in that:
The normal direction of the film polarizer (2) is parallel with direction of beam propagation.
4. a kind of multiple degrees of freedom spectral filter that can compensate for polarization mode dispersion according to claim 1, it is characterised in that:
The length of the additional polarization maintaining optical fibre (5) is selected according to actual needs.
5. a kind of multiple degrees of freedom spectral filter that can compensate for polarization mode dispersion according to claim 1, it is characterised in that:
The polarization maintaining optical fibre (6) of the optical axis rotation is 45 ° to shaft angle degree.
6. -5 any a kind of multiple degrees of freedom spectral filter that can compensate for polarization mode dispersion according to claim 1, special
Sign is: the liquid-crystal controller and the rotation adjustment frame are connected through computer (8) with oscillograph (9) respectively, to realize
Remote closed loop control.
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| CN109212796A (en) * | 2018-10-24 | 2019-01-15 | 北京航空航天大学 | A kind of negative liquid crystal reflective spatial light modulator |
| CN113325568B (en) * | 2021-05-13 | 2023-06-02 | 中国科学院上海光学精密机械研究所 | Liquid crystal-based rapid spectrum imaging system and application method thereof |
| CN117109643B (en) * | 2023-10-24 | 2024-01-02 | 中国科学院长春光学精密机械与物理研究所 | Test method and system using transmission type angle sensor |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6417948B1 (en) * | 1999-12-24 | 2002-07-09 | Corning Incorporated | Variable delay device for an optical component such as a polarization mode dispersion compensator |
| CN1564030A (en) * | 2004-03-19 | 2005-01-12 | 中国科学院上海光学精密机械研究所 | Polarizing membrane dispersion compensator based on optical fiber raster |
| CN1715975A (en) * | 2004-06-30 | 2006-01-04 | 北京大学 | Polarized mode dispersion compensator |
| CN103995393A (en) * | 2014-05-22 | 2014-08-20 | 中国科学院上海光学精密机械研究所 | Laser spectrum compensation device |
| CN105490140A (en) * | 2016-01-19 | 2016-04-13 | 中国工程物理研究院激光聚变研究中心 | Adjustable spectrum modulator and application thereof |
-
2016
- 2016-11-09 CN CN201610982537.1A patent/CN106569357B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6417948B1 (en) * | 1999-12-24 | 2002-07-09 | Corning Incorporated | Variable delay device for an optical component such as a polarization mode dispersion compensator |
| CN1564030A (en) * | 2004-03-19 | 2005-01-12 | 中国科学院上海光学精密机械研究所 | Polarizing membrane dispersion compensator based on optical fiber raster |
| CN1715975A (en) * | 2004-06-30 | 2006-01-04 | 北京大学 | Polarized mode dispersion compensator |
| CN103995393A (en) * | 2014-05-22 | 2014-08-20 | 中国科学院上海光学精密机械研究所 | Laser spectrum compensation device |
| CN105490140A (en) * | 2016-01-19 | 2016-04-13 | 中国工程物理研究院激光聚变研究中心 | Adjustable spectrum modulator and application thereof |
Non-Patent Citations (1)
| Title |
|---|
| Suppression of FM-to-AM modulation by polarizing fiber front end for high-power lasers;Zhi Qiao，et al.;《Applied Optics》;20161010;第55卷(第29期);第8352-8358页 * |
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