CN117249971A - System and method for determining polarization state of optical fiber device - Google Patents
System and method for determining polarization state of optical fiber device Download PDFInfo
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- CN117249971A CN117249971A CN202210651410.7A CN202210651410A CN117249971A CN 117249971 A CN117249971 A CN 117249971A CN 202210651410 A CN202210651410 A CN 202210651410A CN 117249971 A CN117249971 A CN 117249971A
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- 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
- G01M11/02—Testing optical properties
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- 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
- G01M11/02—Testing optical properties
- G01M11/0207—Details of measuring devices
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Abstract
The application provides a system and a method for determining the polarization state of an optical fiber device. The light source device is used for providing light signals and sending the light signals to the polarization control device, the polarization control device comprises a polarizer and a polarization modulator and is sequentially connected with an optical fiber device to be tested, the optical fiber device to be tested is contacted with the polarization controller, and different optical signals can be obtained by the polarization detection device through rotating the optical fiber device, so that the polarization state of the optical fiber device to be tested is determined, and the polarization detection device is a rapid and practical polarization detection means.
Description
Technical Field
The application relates to a system and a method for determining the polarization state of an optical fiber device, and belongs to the field of optical fiber sensing.
Background
Polarization state is an important parameter of an optical fiber device, and can influence the measurement accuracy of the optical fiber device on mechanical, physical and even energy fields. Thus generating a non-negligible importance in biomedical, electrochemical and energy measurements. So far, no very feasible method can quickly and practically determine the polarization state direction of the optical fiber device, mainly because the types of the optical fibers are complex and various, and some testing processes are complicated and cannot introduce the internal polarization into the external polarization, so that the connection between the internal polarization and the external polarization is established. Particularly, in the process of measuring biological detection interface molecules and detecting ions close to an electrode plate by using a battery, the problem of polarization state randomness exists, and if the polarization state direction of the optical fiber device is not matched with the vector direction, the detection depth of an evanescent field at the interface of the optical fiber device can be influenced, so that the sensitivity of detecting biological molecules, polarized ions and other micro substances is influenced. Therefore, there is a need for a solution to these significant problems.
Disclosure of Invention
The application provides a system and a method for determining the polarization state of an optical fiber device, which can quickly and in-situ determine the polarization state of the optical fiber device.
In a first aspect, the present application provides a system for determining the polarization state of an optical fiber device, the system comprising a light source device, a polarization control device, and a polarization detection device; the light source device is used for providing light signals and sending the light signals to the polarization control device; the polarization control device comprises a polarizer and a polarization modulator, wherein the polarizer is connected with the optical fiber device to be tested, and the polarization controller is contacted with the optical fiber device to be tested; the polarization detection device is used for detecting polarization information of the optical fiber device to be detected.
By contacting the device under test with the polarization modulator, the optical signal may be coupled into the polarization modulator to form an asymmetric structure, thereby generating polarization information.
The polarization information is embodied as the spectrum intensity amplitude and wavelength of the optical fiber device to be tested.
In one aspect of the present invention, the polarization control device further includes an optical fiber twister, where the optical fiber twister provides a certain twisting angle for the optical fiber device to be tested, and a correspondence relationship between the twisting angle and polarization information of the optical fiber device to be tested can be established.
In one aspect of the invention, a polarization modulator includes a substrate including an arc substrate, a bar substrate, a sphere substrate, a star substrate, and a cylinder substrate.
In one aspect of the invention, the optical fiber device to be tested comprises one or more of an inclined optical fiber grating, an optical fiber Bragg grating, a long period optical fiber grating, an optical fiber core diameter mismatch device, an optical fiber core dislocation device, a tapered optical fiber, a micro-nano optical fiber device, a photonic crystal optical fiber device, a microstructure optical fiber device, a polymer optical fiber device, a sapphire optical fiber, an optical fiber laser device and an optical fiber coupling device.
In one aspect of the invention, the system further comprises a layer of medium located between the optical fiber device under test and the polarization modulator for effecting or enhancing optical field coupling between the optical fiber device under test and the polarization modulator; the medium comprises one or more of a gas, a liquid, and a solid.
The system utilizes the fiber carrier with sensing and communication functions and electromagnetic interference resistance, obtains polarization information by utilizing an optical means on the premise of not influencing the electromagnetic characteristics of the electrode surface, and clings the optical fiber device to be tested to the surface of the polarization detection device to form an asymmetric environment, so that an energy field can be coupled into the polarization detection device to influence the polarization information of the optical fiber device, and the polarization state of the optical fiber device to be tested can be determined according to the change of the polarization information. The system is simple to build, high in operability and high in practicability.
In a second aspect, there is provided a method of determining the polarization state of an optical fiber device, the method comprising: constructing the system in the first aspect, and controlling the light source to emit a light signal to the polarization control device, wherein the polarization control device comprises a polarizer and a polarization modulator, the optical fiber device to be tested is clung to the polarization modulator, the light signal obtains polarized light through the polarizer, the polarized light passes through the optical fiber twister, and the optical fiber twister modulates the torsion angle of the optical fiber device to be tested to generate the change of polarization information; recording the change of the polarization information by a polarization detection device; and determining the polarization state of the optical fiber device to be tested according to the change of the polarization information.
The polarization state of the optical fiber device under test can be determined by changing according to polarization information of single or multiple modes.
Further, the polarization state of the optical fiber device to be measured is determined according to the single or multiple mode intensity amplitude changes and/or wavelength drift, or the polarization state of the optical fiber device to be measured is determined according to the single or multiple mode spectral area changes.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings may be obtained according to the structures shown in these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a schematic diagram of a system 100 for determining the polarization state of a fiber optic device according to an embodiment of the present invention.
FIG. 2 is a schematic diagram of a reflective system 200 for determining the polarization state of a fiber optic device according to an embodiment of the present invention.
FIG. 3 is a schematic diagram of a method 300 of determining the polarization state of an optical fiber device according to an embodiment of the present invention.
FIG. 4 is a system diagram of an optical fiber device under test in a close proximity to a polarization modulator in accordance with an embodiment of the present invention.
FIG. 5 is a schematic diagram of an oblique fiber grating of a fiber device under test according to an embodiment of the present invention.
FIG. 6 is a graph of optical signals obtained by rotating an optical fiber twister after a fiber device under test is attached to a polarization modulator.
FIG. 6a is a graph of optical signals of mode 1 and mode 2 obtained by rotating an optical fiber twister under a symmetrical environment (without a substrate) of an optical fiber device to be tested, wherein a P state and an S state are generated respectively, and the mode 1 and the mode 2 contain intensity information and wavelength information respectively.
FIG. 6b is a graph of optical signals of mode 1 and mode 2 obtained by rotating an optical fiber twister under an asymmetric environment (with a substrate) for an optical fiber device under test, wherein P-state and S-state are generated respectively, and similarly, mode 1 and mode 2 are sensitive to intensity amplitude modulation and to wavelength modulation respectively
FIG. 7a is a diagram of the spectral integration area of an optical signal of an optical fiber sensor according to an embodiment of the present invention.
Fig. 7b is a spectrum integration area diagram of an optical signal according to the embodiment of the invention, which is obtained after demodulating an integrated spectrum signal and corresponds to a torsion angle.
FIG. 8 is an integrated spectrum of an optical signal obtained by optimizing the integrated area of the optical signal and integrating different areas of the optical signal according to an embodiment of the present invention.
Detailed Description
The technical solutions in the present application will be described below with reference to the accompanying drawings.
Examples:
as shown in fig. 1, an embodiment of the present application provides a system 100 for determining the polarization state of an optical fiber device, the system comprising a light source device 110, a polarization control device 120, and a polarization detection device 130. The polarization control device 120 comprises a polarizer 121 and a polarization modulator 122, wherein the polarizer 121 is connected with the optical fiber device to be tested, and the polarization modulator 122 is in contact with the optical fiber device to be tested.
The light source device 110 is configured to provide an optical signal, and send the optical signal to the polarizer 121 in the polarization control device 120, where the polarizer 121 modulates the optical signal into polarized light, and transmits the polarized light to the optical fiber device to be tested, and the polarization modulator 122, where the optical fiber device to be tested is attached to the surface of the substrate to form an asymmetric environment, so that an energy field can be coupled into the substrate, thereby affecting polarization information of the optical fiber. The optical fiber device to be tested transmits the coupled polarization information to the polarization detection device 130, and the polarization detection device 130 is used for detecting the polarization information of the optical fiber device to be tested.
The contact between the optical fiber device to be measured and the polarization controller 122 may be understood as a seamless contact between the optical fiber device to be measured and the polarization controller, or the optical fiber device to be measured is closely attached to the polarization controller, which may be expressed as that the optical fiber device to be measured is placed on the polarization controller.
Specifically, the polarization information is the change of the dual polarization effect of the optical fiber device to be tested, and specifically, the polarization information is embodied as the spectrum intensity amplitude and the wavelength of the optical fiber device to be tested.
The polarization state of the optical fiber device to be tested can be determined according to the polarization information. The polarization state can be understood as being mainly including linear polarization, elliptical polarization, circular polarization and other forms, and also including two orthogonal P-states (TM) and S-states (TE) of the optical fiber during the birefringence and coupling processes, the application mainly focuses on the P-states and S-states, and since the radial evanescent wave of the P-states is stronger than the evanescent wave of the S-states during the sensing process, the condition also needs the participation of the P-states to make the surface plasmon resonance effect easier to generate and excite.
The light source device 110 includes a broadband light source, a laser light source, a visible light source, an incandescent lamp, an LED, etc., and the laser light source may include a single laser and a tunable laser. Wherein the output range of the broadband light source is 1200-1800nm.
Polarization detection device 130 includes, but is not limited to, a spectrum analyzer, a Photodetector (PD), an analog-to-digital converter (A/D).
Wherein, when the light source device 110 comprises a broadband light source, the polarization detection device 130 comprises a spectrum analyzer; when the light source device 110 includes a laser light source, the polarization detection device 130 includes a photodetector and an analog-to-digital converter.
Alternatively, the light source device 110 and the polarization detection device 130 may be integrated, i.e., the integrated device may emit light signals or may receive and demodulate light signals. Such as a fiber grating demodulator.
Further, the polarization control device also comprises an optical fiber twister, the optical fiber twister provides a certain torsion angle for the optical fiber device to be tested, and the corresponding relation between the torsion angle and polarization information of the optical fiber device to be tested can be established.
Optionally, the polarization modulator includes a substrate including, but not limited to, an arcuate substrate, a bar substrate, a sphere substrate, a star substrate, and a cylinder substrate. It should be understood that, as long as the polarization modulator has a certain contact surface with the optical fiber device to be tested, it is within the scope of the present application. The material of the polarization controller may be polymethyl methacrylate substrate, polycarbonate substrate, and glass substrate. The shape, size, material, thickness, refractive index, etc. of the polarization controller are not limited in this application.
Optionally, the system further includes a layer of medium, which is located between the optical fiber device under test and the polarization modulator, for enhancing or implementing optical field coupling between the optical fiber device under test and the polarization controller, which can also be understood as preventing a gap from occurring between the optical fiber device under test and the polarization modulator; the medium comprises one or more of a gas, a liquid, and a solid. For example, the medium may be water, which is not limited in any way by the present application.
Optionally, the optical fiber device to be tested includes one or more of an oblique optical fiber grating, an optical fiber bragg grating, a long period optical fiber grating, an optical fiber core diameter mismatch device, an optical fiber core dislocation device, a tapered optical fiber, a micro-nano optical fiber device, a photonic crystal optical fiber device, a micro-structure optical fiber device, a polymer optical fiber device, a sapphire optical fiber, an optical fiber laser device, and an optical fiber coupling device.
Further, the optical fiber device to be measured may be a transmission type optical fiber device or a reflection type optical fiber device, wherein when the optical fiber device to be measured is a reflection type optical fiber device, one end face of the optical fiber device is plated with a reflection film (may also be a high reflection film). Specifically, the high-reflection film is divided into two types, that is, a dielectric high-reflection film and a metal high-reflection film. The dielectric high-reflection film is composed of a plurality of layers of insulating dielectric materials. The polarization of this film system is very small and the reflectivity can be very high. The coating of the metal high-reflection film is made of gold, silver or aluminum.
Accordingly, when the optical fiber device to be measured is a reflective optical fiber device, the system for determining the polarization state of the optical fiber device is a reflective system, as shown in fig. 2. Fig. 2 shows a reflection system 200 for determining the polarization state of an optical fiber device according to the present invention, which comprises a light source device 110, a polarization detection device 130, an optical connection device 140 and a polarization control device 120. The light source device 110 and the polarization control device 120 have been described in the relevant portions of fig. 1, and are not described again for brevity.
The optical connection device 140 includes, but is not limited to, an optical circulator, an optical coupler, and an optical fiber combiner, which are disposed in an input optical path between the light source device 110 and the polarization control device 120, and an output optical path between the polarization control device 120 and the polarization detection device 130.
FIG. 3 illustrates a method for determining the polarization state of an optical fiber device using the system of the present application, the method comprising the steps of:
s310, a system for determining the polarization state of the optical fiber device is built, wherein a light source device, a polarization control device and a polarization detection device are sequentially connected.
S320, controlling a light source to emit a light signal to a polarization control device, wherein the polarization control device comprises a polarizer and a polarization modulator, an optical fiber device to be tested is clung to the polarization modulator, the light signal obtains polarized light through the polarizer, the polarized light passes through an optical fiber twister, and the optical fiber twister modulates the torsion angle of the optical fiber device to be tested to generate change of polarization information; recording the change of the polarization information by a polarization detection device;
s330, determining the polarization state of the optical fiber device to be tested according to the change of the polarization information.
Building a proper sensing system according to the type of the optical fiber device to be tested, and building a transmission system according to FIG. 1 when the optical fiber device to be tested is transmission type; when the optical fiber device to be tested is reflective, a reflective system is built according to fig. 2. And then the optical fiber device to be tested can be rotated by using the optical fiber rotator, the torsion angle is adjusted, different belt sides are coupled with the polarization control modulator to generate different polarization information, and the polarization state of the optical fiber device to be tested is determined through the change of the polarization information. In one embodiment of the present application, the polarization state of the optical fiber device under test may be determined based on the change in polarization information of single or multiple modes. Specifically, the polarization state of the optical fiber device to be measured is determined according to the single or multiple mode intensity amplitude changes and/or wavelength drift, or the polarization state of the optical fiber device to be measured is determined according to the single or multiple mode spectral area changes.
In one embodiment of the present application, when a system and method of demodulation mode of a broadband light source in combination with a spectrum analyzer is employed, it determines the polarization state of the optical fiber device under test by wavelength shifts and/or intensity variations of single or multiple modes in the spectrum.
In one embodiment of the present application, when a system and method of demodulation of a combination of a laser source and a photodetector is employed, it determines the polarization state of the fiber optic device under test from single or multiple light intensity variations in the photodetector.
The single mode may be a cladding mode, a core mode (may also be referred to as a guided mode or a transmission mode), a leakage mode, a "soul" mode, a radiation mode, etc., which are not limited in this application. The plurality of modes may be understood as at least two modes, which may determine a polarization state according to a wavelength and an intensity variation of the at least two modes, or may integrate to obtain a spectral area according to the at least two modes, and determine a polarization state according to a variation of the spectral area, which is not limited in this application.
The following description uses a device to be tested as an inclined fiber grating, a reflective system, and a polarization modulator as a planar substrate.
According to the polarization state system for determining the optical fiber device, a reflection system shown in fig. 4 is built. The system comprises a light source 1, a polarizer 2, a circulator 3, a spectrometer 4, an optical fiber twister 5, an optical fiber sensor 6 and a substrate 7 with a certain refractive index, wherein the light source 1, the polarizer 2 and the circulator 3 are sequentially connected, the spectrometer 4 is connected with the circulator 3, the circulator 3 is connected with the optical fiber twister 5, the optical fiber twister 5 is connected with the optical fiber sensor 6, and the optical fiber sensor 6 is tightly attached to the substrate 7 with the certain refractive index.
The structure diagram of the optical fiber device to be tested is shown as 5, the optical fiber device to be tested 6 is a reflective optical fiber device, an oblique Bragg optical fiber grating 8 is carved in the optical fiber device to be tested, a reflecting film 9 is plated on the end face of the optical fiber sensor, light emitted by the light source 1 sequentially passes through the polarizer 2, the circulator 3 and the optical fiber twister 5 and then enters the optical fiber sensor 6, the light reflected by the optical fiber sensor 6 is input into the spectrometer 4 through the circulator 3, the oblique Bragg optical fiber grating 8 in the optical fiber sensor 6 couples the optical coupling of the optical fiber core mode to the evanescent wave optical field 10 of the higher-order cladding mode and the substrate on the surface of the optical fiber sensor to each other, the phenomenon is displayed in the spectrometer 4, and the caused cladding mode double polarization effect change can be displayed through the spectrometer 4; it will be understood by those skilled in the art that the circulator 3 may be replaced by an optical fiber combiner, and the inclined bragg fiber grating may be replaced by one of bragg fiber gratings, long period fiber gratings, single mode fiber-multimode fiber-single mode fiber interference devices, single mode fiber-coreless fiber-single mode fiber interference devices, micro-nano fiber devices, and other fiber devices having a polarization effect. The present application is not limited in this regard.
Since the high polarization dependence of the tilted fiber grating is determined by both its inherent guided mode characteristics and non-cylindrical symmetry, when the direction of the grating plane of the tilted fiber grating matches with the internal polarized light, the cladding mode of the tilted fiber grating will exhibit a very strong polarization dependence, wherein two orthogonally polarized polarization modes, namely a polarization electric field S-pol tangential to the fiber section and a polarization electric field P-pol radial to the fiber section, are induced. Therefore, the direction of the polarization state can be determined by utilizing the mode birefringence effect, and the polarization state of the inclined fiber grating can be determined by introducing a substrate with a certain refractive index to form an asymmetric structure so as to amplify the double polarization effect.
In one possible implementation, the determination of the polarization direction of the optical fiber device by the tilted bragg fiber grating sensor (i.e., the fiber sensor with the tilted bragg fiber grating) may be achieved by monitoring the wavelength shift or the change in intensity of the cladding modes in the output spectrum: specifically, as shown in fig. 6a, the situation of no substrate (or no contact between the inclined bragg fiber grating and the substrate) in the present application is shown, namely, the schematic diagram and the optical signal diagram of the inclined bragg fiber grating under the symmetrical condition; FIG. 6b is a schematic diagram and an optical signal diagram of an asymmetric condition of the substrate (or the inclined Bragg grating is in contact with the substrate) in the present application, i.e. the inclined Bragg grating is closely attached to the substrate with a certain refractive index; by comparing the optical signals in fig. 6a and fig. 6b, it is apparent that the intensity and wavelength of the mode are changed after the substrate is introduced to form an asymmetric condition, the wavelength range of the mode 1 is 1518.78nm, the mode is P-state under low amplitude, the mode is S-state under high amplitude, after the substrate is introduced back and forth to form an asymmetric condition, the amplitude change between the P, S states of the mode optical intensity is obvious, the mode 2 at 15332.68nm, the P-state at short wavelength, the S-state at long wavelength, the amplitude change of the mode optical P, S is 0.23db, the wavelength change between the P and S is obvious, and the space is changed from 0.04nm to 0.02 nm.
In another possible implementation, the polarization state of the tilted fiber bragg grating sensor may be determined for a plurality of modes. Specifically, integration of single or multiple modes to obtain spectral area may be employed to determine polarization state. Fig. 7a shows the spectral integration area for multiple modes. The spectrum integral area obtaining mode comprises fitting the upper and lower envelopes of a plurality of modes, and integrating the spectrum area surrounded by the upper and lower envelopes; fig. 7b shows a spectrum integration area diagram of the inclined bragg fiber grating along with the change of the torsion angle of the optical fiber under the asymmetric condition of the substrate with a certain refractive index. In the process, a main peak and a secondary peak periodically appear, and the area difference between the main peak and the secondary peak is about 20% -30%, because the energy distribution on the surface of the grating is uneven, in the process of twisting the optical fiber twister, the effect similar to that of an analyzer can occur in the process of linearly polarized light coupling provided by a polarizer reflected by a reflecting film, certain modulation change is generated when the modes are collected front and back, the polarization state corresponding to the main peak is S state, and the polarization state corresponding to the secondary peak is P state. Thus, the spectral area of a single mode or multiple modes can be used to determine the polarization state of the fiber optic device under test.
Further, the optimization of the method for determining the polarization state direction of the optical fiber device is realized, specifically: the spectrum integration areas surrounded by the upper and lower envelope fitting of different ranges are integrated (namely, the spectrum integration areas surrounded by the upper and lower envelope fitting are calculated for a single mode or a plurality of modes), the inclined Bragg fiber bragg grating shown in fig. 8 is clung to a substrate with a certain refractive index to form an asymmetric condition, and the spectrum integration areas are integrated for 1500-1575nm, 1520-1580nm and 1520-1560nm respectively, so that a main peak and a secondary peak can periodically appear in the process, wherein the difference value of the main peak and the secondary peak is 19.43%, 30.82% and 32.64% respectively. The spectrum area surrounded by the upper envelope and the lower envelope of the cladding mode in the integral spectrum is periodically changed in the twisting process of clinging to a substrate with a certain refractive index, wherein the obtained spectrum integral area comprises a main peak signal and a secondary peak signal, and the quantitative measurement of the polarization state direction of an optical fiber device and the determination of the polarization state direction can be realized by analyzing the angle positions of the spectrum integral area and the optical secondary peak signal.
The foregoing is merely specific embodiments of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily think about changes or substitutions within the technical scope of the present application, and the changes and substitutions are intended to be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.
Claims (10)
1. A system for determining the polarization state of a fiber optic device, comprising: a light source device, a polarization control device and a polarization detection device;
the light source device is used for providing an optical signal and sending the optical signal to the polarization control device;
the polarization control device comprises a polarizer and a polarization modulator, wherein the polarizer is connected with the optical fiber device to be tested, and the polarization modulator is contacted with the optical fiber device to be tested;
the polarization detection device is used for detecting polarization information of the optical fiber device to be detected.
2. The system of claim 1, wherein the polarization information is a spectral intensity amplitude and a wavelength of the optical fiber device under test.
3. The system of claim 1, wherein the polarization control device further comprises an optical fiber twister, the optical fiber twister providing a certain twisting angle for the optical fiber device to be tested, and a correspondence relationship between the twisting angle of the optical fiber device to be tested and the polarization information can be established.
4. The system of claim 1, wherein the polarization modulator comprises a substrate comprising an arcuate substrate, a bar substrate, a sphere substrate, a star substrate, and a cylinder substrate.
5. The system of claim 1, wherein the fiber device under test comprises one or more of a tilted fiber grating, a fiber bragg grating, a long period fiber grating, a fiber core diameter mismatch device, a fiber core misalignment device, a tapered fiber, a micro-nano fiber device, a photonic crystal fiber device, a microstructured fiber device, a polymer fiber device, a sapphire fiber, a fiber laser device, a fiber coupling device.
6. The apparatus of claim 1, wherein the system further comprises a layer of medium between the optical fiber device under test and the polarization modulator for effecting or enhancing optical field coupling between the optical fiber device under test and the polarization modulator; the medium comprises one or more of a gas, a liquid, and a solid.
7. A method of determining the polarization state of an optical fiber device, the method comprising:
constructing a system according to any one of claims 1-6;
the method comprises the steps of controlling a light source to emit light signals to a polarization control device, wherein the polarization control device comprises a polarizer and a polarization modulator, an optical fiber device to be tested is clung to the polarization modulator, the light signals obtain polarized light through the polarizer, the polarized light passes through an optical fiber twister, and the optical fiber twister modulates the twisting angle of the optical fiber device to be tested to generate change of polarization information; recording the change of the polarization information by a polarization detection device;
and determining the polarization state of the optical fiber device to be tested according to the change of the polarization information.
8. The method of claim 7, wherein determining the polarization state of the optical fiber device under test based on the change in polarization information comprises:
and determining the polarization state of the optical fiber device to be tested according to the polarization information change of the single or multiple modes.
9. The method of claim 8, wherein determining the polarization state of the optical fiber device under test based on the change in polarization information for the single or multiple modes comprises:
and determining the polarization state of the optical fiber device to be tested according to the single or multiple mode intensity amplitude changes and/or wavelength drift.
10. The method of claim 8, wherein determining the polarization state of the optical fiber device under test based on the change in polarization information for the single or multiple modes comprises:
and determining the polarization state of the optical fiber device to be tested according to the change of the spectral area of the single mode or the multiple modes.
Priority Applications (1)
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