CN108007307B - Optical fiber measuring method and measuring device - Google Patents
Optical fiber measuring method and measuring device Download PDFInfo
- Publication number
- CN108007307B CN108007307B CN201711156962.6A CN201711156962A CN108007307B CN 108007307 B CN108007307 B CN 108007307B CN 201711156962 A CN201711156962 A CN 201711156962A CN 108007307 B CN108007307 B CN 108007307B
- Authority
- CN
- China
- Prior art keywords
- signal
- interferometer
- optical fiber
- length
- radio frequency
- 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.)
- Active
Links
- 239000013307 optical fiber Substances 0.000 title claims abstract description 153
- 238000000034 method Methods 0.000 title claims abstract description 54
- 238000002156 mixing Methods 0.000 claims abstract description 49
- 238000005259 measurement Methods 0.000 claims abstract description 35
- 239000000835 fiber Substances 0.000 claims abstract description 30
- 238000012360 testing method Methods 0.000 claims abstract description 17
- 230000014509 gene expression Effects 0.000 claims description 43
- 238000001914 filtration Methods 0.000 claims description 26
- 238000012545 processing Methods 0.000 claims description 18
- 101710118890 Photosystem II reaction center protein Ycf12 Proteins 0.000 claims description 9
- 230000000903 blocking effect Effects 0.000 claims description 8
- 238000004364 calculation method Methods 0.000 claims description 5
- 230000008054 signal transmission Effects 0.000 claims description 5
- 238000000691 measurement method Methods 0.000 claims description 2
- 230000003287 optical effect Effects 0.000 description 10
- 238000005070 sampling Methods 0.000 description 10
- 238000010586 diagram Methods 0.000 description 5
- 238000005516 engineering process Methods 0.000 description 3
- 238000005057 refrigeration Methods 0.000 description 3
- 230000035559 beat frequency Effects 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000001816 cooling Methods 0.000 description 2
- 238000001028 reflection method Methods 0.000 description 2
- 238000003786 synthesis reaction Methods 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 1
- 230000001427 coherent effect Effects 0.000 description 1
- 238000009795 derivation Methods 0.000 description 1
- 238000012938 design process Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 238000010408 sweeping Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B5/00—Measuring arrangements characterised by the use of mechanical techniques
- G01B5/02—Measuring arrangements characterised by the use of mechanical techniques for measuring length, width or thickness
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M11/00—Testing of optical apparatus; Testing structures by optical methods not otherwise provided for
- G01M11/30—Testing of optical devices, constituted by fibre optics or optical waveguides
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Testing Of Optical Devices Or Fibers (AREA)
- Investigating Or Analysing Materials By Optical Means (AREA)
Abstract
The invention discloses a measuring method and a measuring device of an optical fiber, wherein the method comprises the following steps: step 1: acquiring a first relation between the length of a long arm and the length of a short arm of the interferometer by using the mixed signal; step 2: the optical fiber to be measured is connected to a long arm in the interferometer, and a second relation between the length of the long arm and the length of the short arm of the interferometer after the optical fiber to be measured is connected is obtained by utilizing the mixing signal; step 3: calculating the length L or refractive index n of the known optical fiber to be measured according to the first relation and the second relation 0 Refractive index n of the fiber under test 0 Or length L. The method can accurately calculate the length or refractive index of the optical fiber to be measured, and meets the requirement of high-precision measurement of the length of the optical fiber.
Description
Technical Field
The invention belongs to the technical field of optical interferometer measurement, and particularly relates to a measuring method and a measuring device for an optical fiber.
Background
Various optical instruments based on the optical interference technology have the advantages of high measurement precision, high sensitivity and strong anti-interference capability. The method can be widely applied to measurement of physical quantities such as length, temperature, refractive index, pressure, magnetic field and the like. The mature scheme of the current optical fiber length measurement technology comprises an optical time domain reflectometer, an optical frequency domain reflectometer and an optical coherence function method.
The main principle of the method is that a light pulse with a narrow pulse width is emitted and injected into an optical fiber, a reflecting mirror is placed at the tail end of the optical fiber, the light pulse is emitted by the reflecting mirror and then returns to an emitting end to be detected by an instrument, and the instrument calculates the length of the optical fiber by calculating the time difference between the emitted pulse and the reflected pulse. The measuring method has a large measuring range, but the measuring precision is at the centimeter level at most, and the precision of the current commercial optical time domain reflectometer equipment is at the meter level at most, so the method is not suitable for measuring the length of the short-distance optical fiber.
The main principle of the optical frequency domain reflection method is that an adjustable laser is used as a sweep frequency source, light emitted by a light source is equally divided into two beams by a coupler, and one beam enters a reference arm and is reflected back to the coupler by a reflector to serve as square reference light; the other beam enters the test optical fiber and returns to the coupler to interfere with the reference light in beat frequency after being reflected, the beat frequency is measured, and the transmission time of the test light in the test optical fiber can be calculated according to the sweep slope of the laser, so that the optical fiber length is obtained. The method has the characteristics of high cost and low stability.
The optical coherence domain reflection method is based on the fact that light passes through optical fibers with different lengths and has a time difference r, and a laser source generates a sweep optical signal. The measurement of the length of the optical fiber can be achieved by varying the scanning period T. However, this method has the disadvantages of low resolution and long measurement time.
The above three optical fiber length measurement technologies cannot meet the requirement of high-precision measurement of short-distance optical fiber length, and cause great difficulty in designing, producing and testing optical fibers, because it is necessary to provide an optical fiber measurement device and a measurement method for realizing high-precision measurement of short-distance optical fiber length.
Disclosure of Invention
The invention aims to provide an optical fiber measuring method and an optical fiber measuring device, which realize high-precision measurement of the length of a short-distance optical fiber.
The invention provides an optical fiber measuring method, which comprises the following steps:
step 1: acquiring a first relation between the length of a long arm and the length of a short arm of the interferometer by using the mixed signal;
the first relation expression shows the relation between the length of the long arm and the length of the short arm of the interferometer and the difference between two frequencies which are different by one period in the radio frequency signal before the interferometer is connected to the optical fiber to be measured;
step 2: the optical fiber to be measured is connected to a long arm in the interferometer, and a second relation between the length of the long arm and the length of the short arm of the interferometer after the optical fiber to be measured is connected is obtained by utilizing the mixing signal;
the second relation expression shows the relation between the length of the long arm and the short arm of the interferometer and the difference between two frequencies which are different by one period in the radio frequency signal after the long arm of the interferometer is connected with the optical fiber to be measured;
step 3: calculating the length L or refractive index n of the known optical fiber to be measured according to the first relation and the second relation 0 Refractive index n of the fiber under test 0 Or length L;
the frequency mixing signals used in the step 1 and the step 2 are obtained by inputting one path of signal of the radio frequency signal with continuously changing frequency into the interferometer before the optical fiber to be detected is connected into the interferometer and after the optical fiber to be detected is connected into the interferometer, and then carrying out frequency mixing processing on the output signal of the interferometer and the other path of signal of the radio frequency signal;
the signal transmission process in the step 1 and the step 2 is as follows:
extracting radio frequency signals with continuously-changed frequency emitted by a sweep frequency signal source into two identical paths of signals, wherein the two identical paths of signals are a first signal and a second signal, modulating a broadband light source by utilizing the first signal and inputting the first signal into an interferometer, mixing an output signal of the interferometer with the second signal after DC blocking and phase shifting treatment, and transmitting the mixed signal to an acquisition module after filtering treatment, wherein the acquisition module acquires an electric signal power minimum point in each of two continuous periods in monitored electric signal power data in the frequency change process of the radio frequency signals, and acquires the frequency of the radio frequency signal corresponding to the two electric signal power minimum points;
the method comprises the steps of acquiring two radio frequency signals corresponding to the minimum point of the power of the two electric signals by an acquisition module, wherein the two frequencies are separated by a period, and calculating a relation between the length of a long arm and the length of a short arm of an interferometer by using the frequency acquired by the sampling module and an input signal of the sampling module.
After the electric signal power minimum points in two continuous periods acquired by the acquisition module, the two frequencies of the radio frequency signals corresponding to the two power minimum points are different by one period. When the length L of the optical fiber to be measured is known, the refractive index n of the optical fiber to be measured can be calculated by adopting the method 0 The method comprises the steps of carrying out a first treatment on the surface of the When the refractive index n of the optical fiber to be measured is known 0 The length L of the optical fiber to be measured can be calculated by adopting the method.
Preferably, when the period of the radio frequency signal is 2pi, the first relation is as follows:
the second relation is as follows:
obtaining the refractive index n of the known optical fiber to be tested 0 When the length L of the optical fiber to be measured is calculated as follows:
when the length L of the optical fiber to be measured is known, the refractive index n of the optical fiber to be measured is obtained 0 The calculation formula of (2) is as follows:
wherein l 1 Interferometer long arm indicating that optical fiber to be measured is not connectedLength of l 2 Representing the length of the interferometer short arm, c is the speed of light in vacuum, n is the refractive index of the interferometer fiber, f 11 And f 12 The method comprises the steps that 1, the frequency of a radio frequency signal corresponding to the minimum point of two electric signal power measured by an acquisition module when the radio frequency signal is changed is obtained; f (f) 21 And f 22 And 2, the frequency of the radio frequency signal corresponding to the minimum point of the two electric signal powers measured by the acquisition module when the radio frequency signal changes in the step 2.
Preferably, the radio frequency signal is a cosine signal or a sine signal.
Preferably, the signal transmission process in step 1 and step 2 includes the steps of:
step 21: dividing a radio frequency signal emitted by a sweep frequency signal source into a first signal RF11 and a second signal RF12 which are identical;
wherein the expressions of the first signal RF11 and the second signal RF12 are as follows:
Acos(ω 1 t) or Asin (omega) 1 t+π/2)
Wherein A represents the amplitudes of the first and second signals, ω 1 The angular frequency of the first signal and the second signal, t representing time;
step 22: modulating a broadband light source with the first signal;
wherein the expression of the modulated light is as follows:
I 0 +I 0 ·m·cos(ω 1 t)
wherein I is 0 The light intensity is represented, and m represents the modulation degree of light source modulation;
step 23: inputting the light modulated in the step 22 to an interferometer to obtain an output signal;
the expression of the output signal of step 23 is:
step 24: inputting the output signal of the step 23 to a photoelectric detector for DC blocking processing to obtain an output signal RF22;
the expression of the signal RF22 is:
step 25: the signal RF22 is phase-shifted to become a signal RF23;
the expression of the signal RF23 is:
step 26: mixing the signal RF23 in step 25 with the second signal RF12 to obtain a mixed signal;
wherein, the expression of the mixing signal is:
step 27: filtering the mixed signal by a filtering module to obtain an output signal, and inputting the output signal to an AD sampler:
wherein, the expression of the output signal of step 27 is:
wherein, the signal in step 1 satisfies:
the signal in step 3 satisfies:
the interferometer coupler split ratio was 0.5.
Preferably, according to the output signal of step 27, the frequency of the radio frequency signal corresponding to the minimum point of the two electric signal powers detected by the acquisition module in step 1 satisfies a third relational expression;
wherein the third relation is as follows:
(ω 11 ·n·l 1 )/c-(ω 11 ·n·l 2 )/c＝2π+(ω 12 ·n·l 1 )/c-(ω 12 ·n·l 2 )/c
ω 11 ＝2πf 11
ω 12 ＝2πf 12
ω 11 and omega 12 The angular frequency of the radio frequency signal corresponding to the minimum point of the two electric signal powers detected by the AD sampler in the step 1;
according to the output signal of the step 27, the frequency of the radio frequency signal corresponding to the minimum point of the two electric signal powers detected by the acquisition module in the step 2 meets a fourth relational expression;
wherein the fourth relation is as follows:
ω 21 (n·l 1 +n 0 ·L)/c-(ω 21 ·n·l 2 )/c＝2π+ω 22 (n·l 1 +n 0 ·L)/c-(ω 22 ·n·l 2 )/c
ω 21 ＝2πf 21
ω 22 ＝2πf 22
ω 21 and omega 22 The angular frequency of the radio frequency signal corresponding to the minimum point of the two electric signal powers detected by the acquisition module in the step 2.
The power of the electrical signal detected by the acquisition module is the value of the output signal in step 27.
Preferably, the optical fiber to be measured is a faraday rotator mirror pigtail.
On the other hand, the invention also provides a measuring device of the optical fiber, which comprises: the device comprises a light source module, a sweep frequency signal source, a power divider, an interferometer, a photoelectric detector, a phase shifting module, a mixing module, a filtering module, an AD sampler and a measurement processor;
the power divider is used for extracting radio frequency signals with continuously changing frequencies of the sweep frequency signal source into two identical paths of signals, wherein the two paths of signals are a first signal and a second signal;
one end of the power divider is connected with the light source module, the other end of the power divider is connected with the frequency mixing module, the first signal is transmitted to the light source module to modulate a broadband light source of the light source module, and the second signal is transmitted to the frequency mixing module;
the light source module, the interferometer, the photoelectric detector, the phase shifting module and the mixing module are sequentially connected;
the light source module is used for transmitting the modulated light signals to the interferometer, the photoelectric detector is used for performing direct current blocking processing on the output signals of the interferometer, the phase shifting module is used for performing phase shifting processing on the output signals of the photoelectric detector, and transmitting the signals after the phase shifting processing to the mixing module;
the mixing module, the filtering module, the AD sampler and the measurement processor are sequentially connected;
the frequency mixing module is used for carrying out frequency mixing processing on the second signal and the output signal of the phase shifting module;
the filtering module is used for filtering high-frequency components in the mixed signals and transmitting the high-frequency components to the AD sampler;
the AD sampler is used for acquiring an electric signal power minimum point in each of two continuous periods in the monitored electric signal power data in the frequency change process of the radio frequency signal, and acquiring the frequency of the radio frequency signal corresponding to the two electric signal power minimum points; the measuring processor is used for calculating a relation between a long arm and a short arm of the interferometer according to the frequency of the radio frequency signal acquired by the AD sampler;
wherein, the two frequencies of the radio frequency signal corresponding to the minimum point of the two electric signal powers obtained by the AD sampler are separated by a period;
before a long arm of the interferometer is connected with an optical fiber to be measured, the measurement processor obtains a first relation between the length of the long arm and the length of the short arm of the interferometer according to the frequency change of a radio frequency signal of a sweep frequency signal source;
the first relation expression shows the relation between the length of the long arm and the length of the short arm of the interferometer and the difference between the two frequencies of the radio frequency signals acquired by the AD sampler before the optical fiber to be detected is accessed;
after the long arm of the interferometer is connected with the optical fiber to be measured, the measurement processor obtains a second relation between the length of the long arm and the length of the short arm of the interferometer connected with the optical fiber to be measured according to the frequency change of the radio frequency signal of the sweep frequency signal source;
the second relation represents the relation between the length of the long arm and the short arm of the interferometer and the difference between the two frequencies of the radio frequency signals acquired by the AD sampler after the long arm of the interferometer is connected with the optical fiber to be detected;
the measurement processor is used for calculating the length L or the refractive index n of the known optical fiber to be measured according to the first relational expression and the second relational expression 0 Refractive index n of the fiber under test 0 Or length L.
Wherein the first relation is as follows:
the second relationship is as follows:
obtaining the refractive index n of the known optical fiber to be tested 0 When the length L of the optical fiber to be measured is calculated as follows:
when the length L of the optical fiber to be measured is known, the refractive index n of the optical fiber to be measured is obtained 0 The calculation formula of (2) is as follows:
wherein l 1 Indicating the length of the interferometer long arm without accessing the fiber to be measured, l 2 Representing the length of the interferometer short arm, c is the speed of light in vacuum, n is the refractive index of the interferometer fiber, f 11 And f 12 Before the interferometer long arm is connected with the optical fiber to be measured, the frequency of the radio frequency signal corresponding to the minimum point of the two electric signal power measured by the AD sampler in the process of changing the radio frequency signal; f (f) 21 And f 22 When the interferometer long arm is connected with the optical fiber to be measured, the AD sampler measures the frequency of the radio frequency signal corresponding to the minimum point of the two electric signal powers in the radio frequency signal change process.
The phase shifting module, the mixing module and the filtering module are realized in a hardware or software mode, and when the phase shifting module, the mixing module and the filtering module are realized in a hardware mode, the filtering module is preferably a low-pass filter, and the low-pass filter is selected to be one of a source low-pass filter, an RC low-pass filter or an LC low-pass filter. The interferometer may be a Michelson interferometer or a Mach-Zehnder interferometer. The implementation of the signal generated by the swept frequency signal source can be a direct frequency synthesis technique or a phase locked loop technique. As the frequency of the radio frequency signal of the sweep frequency signal source changes, the power of the electric signal detected by the AD sampler also changes.
Preferably, the light source module includes a broadband light source and a modulator;
the broadband light source is connected with the modulator, the power divider and the interferometer are connected with the modulator, and the modulator is used for modulating the intensity of the broadband light source by using the first signal.
Preferably, the modulator is any one of an electro-optical modulator, an acousto-optic modulator and a mechanical chopper.
Preferably, the light source module comprises a direct current power supply and a broadband light source;
the power divider and the interferometer are connected with the broadband light source, and the DC power supply provides bias current for the broadband light source.
The broadband light source can be any one of SLD, SLED, LED, ASE light sources, and the driving waveform for intensity modulating the broadband light source is sine wave or cosine wave.
The photoelectric detector is one of a pyroelectric detector, a photomultiplier tube, an infrared detector, an avalanche diode, a phototriode, a photodiode, a photocell, a photoelectric double diode and a photoresistor.
Advantageous effects
Compared with the prior art, the method and the device have the advantages that the length of the optical fiber to be measured with known refractive index or the refractive index of the optical fiber to be measured with known length is calculated through the first relation between the length of the long arm and the length of the short arm of the interferometer before the optical fiber to be measured is not connected to the optical fiber to be measured and the second relation between the length of the long arm of the interferometer after the optical fiber to be measured is connected to the long arm of the interferometer is calculated. The invention can calculate the length of the optical fiber to be measured by the method to realize high-precision measurement of the length of the optical fiber to be measured no matter for short distance or long distance, the signal can change after the optical fiber to be measured is connected with the long arm of the interferometer, and the invention adopts equipment such as an AD sampler to acquire the signal, so that the change of the signal can be accurately identified, the length of the optical fiber to be measured can be calculated, and the high-precision measurement requirement of the optical fiber length can be met. In addition, the invention can also be used for calculating the refractive index of the optical fiber to be measured, and realizing the measurement of various parameters of the optical fiber.
Furthermore, the invention can realize the measurement of the length of the tail fiber of the Faraday rotator mirror, and the prior art usually adopts a tape measure mode for measuring the length of the tail fiber of the Faraday rotator mirror in the manufacturing process, and has the characteristics of low measurement precision, low efficiency and mechanical damage to the tail fiber, so the mode of the invention has the characteristics of high precision, high efficiency and no damage compared with the traditional mode of measuring the tail fiber of the Faraday rotator mirror.
Drawings
FIG. 1 is a schematic diagram of an optical fiber measurement device according to one embodiment of the present invention;
FIG. 2 is a schematic diagram of an optical fiber measuring device according to another embodiment of the present invention;
fig. 3 is a schematic diagram of a michelson optical fiber interferometer provided by the present invention.
Detailed Description
The invention will be further illustrated with reference to examples.
The invention provides an optical fiber measuring device which is used for measuring the length of an optical fiber or the refractive index of the optical fiber. The measuring device comprises a light source module, a sweep frequency signal source, a power divider, an interferometer, a photoelectric detector, a phase shifting module, a mixing module, a filtering module, an AD sampler and a measuring processor.
The sweep frequency signal source is connected with the power divider, and the light source module and the frequency mixing module are respectively connected with the power divider.
The frequency sweep signal source is used for generating a radio frequency signal with continuously changing frequency. The power divider is used for distributing the power of the sweep frequency signal source, and specifically, the radio frequency signals of the sweep frequency signal source are extracted into two identical paths of signals, wherein the two paths of signals are a first signal and a second signal, the first signal is transmitted to the light source module to be used for modulating the broadband light source of the light source module, and the second signal is transmitted to the frequency mixing module to be subjected to frequency mixing processing.
The light source module, the interferometer, the photoelectric detector, the phase shifting module and the mixing module are sequentially connected.
The light source module is used for transmitting the modulated light signals to the interferometer, the photoelectric detector is used for conducting direct current blocking processing on the output signals of the interferometer, the phase shifting module is used for conducting phase shifting processing on the output signals of the photoelectric detector, the phase-shifted signals are transmitted to the mixing module, and the mixing module is used for conducting mixing processing on the second signals and the output signals of the phase shifting module.
The mixing module, the filtering module, the AD sampler and the measurement processor are sequentially connected.
The filtering module is used for filtering out high-frequency components in the mixed signals and transmitting the high-frequency components to the AD sampler; the AD sampler is used for data acquisition. The measuring processor is used for controlling the signal source and processing the data acquired by the AD collector to calculate the length or refractive index of the optical fiber to be measured.
Wherein, along with the frequency change of the radio frequency signal of the sweep frequency signal source, the power of the electric signal detected by the AD sampler also changes along with the frequency change. The length or refractive index of the optical fiber to be measured is measured by using the measuring device:
and the AD sampler acquires the minimum point of the electric signal power in two continuous periods in the monitored electric signal power data along with the frequency change of the radio frequency signal of the sweep frequency signal source by using the measuring device without accessing the optical fiber to be measured, and acquires the frequency of the radio frequency signal corresponding to the minimum point of the electric signal power. The measurement processor calculates a first relation between a long arm and a short arm of the interferometer according to the frequency of the radio frequency signal acquired by the AD sampler;
and accessing the optical fiber to be detected into a long arm of the interferometer, and utilizing the measuring device, along with the frequency change of the radio frequency signal of the sweep frequency signal source, acquiring an electric signal power minimum point in each of two continuous periods in the monitored electric signal power data by the AD sampler, and acquiring the frequency of the radio frequency signal corresponding to the two electric signal power minimum points. The measuring processor calculates a second relation between a long arm and a short arm of the interferometer connected with the optical fiber to be measured according to the frequency of the radio frequency signal acquired by the AD sampler;
the measurement processor is used for calculating the length L or the refractive index n of the optical fiber to be measured according to the first relation and the second relation 0 。
Wherein the first relation is as follows:
the second relationship is as follows:
obtaining the refractive index n of the known optical fiber to be tested 0 When the length L of the optical fiber to be measured is calculated as follows:
when the length L of the optical fiber to be measured is known, the refractive index n of the optical fiber to be measured is obtained 0 The calculation formula of (2) is as follows:
wherein l 1 Indicating the length of the interferometer long arm without accessing the fiber to be measured, l 2 Representing the length of the interferometer short arm, c is the speed of light in vacuum, n is the refractive index of the interferometer fiber, f 11 And f 12 Before the interferometer long arm is connected with the optical fiber to be measured, the frequency of the radio frequency signal corresponding to the minimum point of the two electric signal power measured by the AD sampler in the process of changing the radio frequency signal; f (f) 21 And f 22 When the interferometer long arm is connected with the optical fiber to be measured, the AD sampler measures the frequency of the radio frequency signal corresponding to the minimum point of the two electric signal powers in the radio frequency signal change process.
The phase shifting module, the mixing module and the filtering module are realized in a hardware or software mode, and when the phase shifting module, the mixing module and the filtering module are realized in a hardware mode, the filtering module is preferably a low-pass filter, and the low-pass filter is selected to be one of a source low-pass filter, an RC low-pass filter or an LC low-pass filter. When the phase shifting module is implemented in a hardware manner, the phase shifting module may be a phase shifter, and preferably the phase shifter is one of an inductance phase shifter, a resistance phase shifter and a capacitance phase shifter described below. When the mixing module is implemented in hardware, the mixing module may be a mixer. The interferometer may be a Michelson interferometer or a Mach-Zehnder interferometer. The implementation of the signal generated by the swept frequency signal source can be a direct frequency synthesis technique or a phase locked loop technique.
The photoelectric detector is one of a pyroelectric detector, a photomultiplier tube, an infrared detector, an avalanche diode, a phototriode, a photodiode, a photocell, a photoelectric double diode and a photoresistor.
In some embodiments, as shown in fig. 1, the light source module includes a broadband light source and a modulator, the broadband light source is coupled to the modulator, both the power divider and the interferometer are coupled to the modulator, and the modulator is configured to intensity modulate the broadband light source with the first signal. Preferably, the modulator is one of an electro-optic modulator, an acousto-optic modulator, and a mechanical chopper.
In other embodiments, as shown in fig. 2, the light source module includes a dc power source and a broadband light source, the dc power source is connected to the broadband light source, the power divider and the interferometer are both connected to the broadband light source, and the dc power source provides a bias current to the broadband light source.
It should be noted that, the broadband light source in the light source module includes, but is not limited to, a SLD, SLED, LED, ASE light source, and the broadband light source further includes a refrigeration module, and the refrigeration mode includes, but is not limited to: air cooling, water cooling, peltier refrigeration and the like. The intensity modulated drive waveforms of the broadband light source include, but are not limited to, sine waves, cosine waves. The intensity modulation of the broadband light source is realized by means of internal modulation and external modulation.
Example 1
Based on the above description of the measuring device, the schematic diagram of the measuring device in embodiment 1 provided by the present invention, as shown in fig. 1, where the measuring device in embodiment 1 includes a broadband light source, a modulator, a swept signal source, a power divider, a michelson optical fiber interferometer, a photodetector, a phase shifter, a mixer, a low-pass filter, an AD sampler, and a measurement processor.
The device comprises a sweep frequency signal source, a modulator, a Michelson optical fiber interferometer, a photoelectric detector, a phase shifter and a mixer, wherein the sweep frequency signal source is connected with the power divider, the broadband light source is connected with the modulator, the modulator and the mixer are respectively connected with the power divider, and the modulator is sequentially connected with the Michelson optical fiber interferometer, the photoelectric detector, the phase shifter and the mixer; the mixer is connected with the low-pass filter, the AD sampler and the measurement processor in sequence.
In this embodiment, the modulation frequency of the modulator is changed to perform intensity modulation on the light emitted from the broadband light source.
Example 2
Based on the above description of the measuring device, the schematic diagram of the measuring device in embodiment 2 provided by the present invention is shown in fig. 2, where the measuring device in embodiment 2 includes a dc power supply, a broadband light source, a swept signal source, a power divider, a michelson optical fiber interferometer, a photodetector, a phase shifter, a mixer, a low-pass filter, an AD sampler, and a measurement processor.
The frequency sweeping signal source is connected with the power divider, the direct current power supply is connected with the broadband light source, the broadband light source and the mixer are respectively connected with the power divider, and the modulator is sequentially connected with the Michelson optical fiber interferometer, the photoelectric detector, the phase shifter and the mixer; the mixer is connected with the low-pass filter, the AD sampler and the measurement processor in sequence.
In this embodiment, the dc power supply provides a bias current to the broadband light source, and the light of the broadband light source is intensity modulated by using the first signal transmitted by the power divider. The optical fiber to be measured is the Faraday rotator mirror tail optical fiber to be measured.
The interferometers used in the embodiment 1 and the embodiment 2 are michelson optical fiber interferometers, as shown in fig. 3, in the michelson optical fiber interferometers, the two optical fiber end faces of the optical fiber coupler of one long tail fiber are coated with high reflection films, coherent light emitted by the laser enters the reference arm and the signal arm optical fiber respectively after being split by the optical fiber coupler, the two light beams are returned to the coupler for converging and coherence after being reflected by the end faces, interference fringes are formed and detected by the detector, the signal arm optical fiber is placed in a detected signal field, and the signal field modulates the phase of the signal arm, so that the detection of the phase difference of the interferometer can be realized. The Michelson fiber optic interferometer only needs one coupler, but the light returned by the end surface reflecting film interferes with the light source, the testing precision is affected, and an isolator is usually added at the output end of the light source to eliminate the influence of the reflected light on the light source.
In which fig. 1 and 2 are only schematic illustrations of the test device, it is foreseen that an actual measuring device should also comprise corresponding mechanical structures to provide mounting, fixing, protection etc. functions.
Taking the measuring device shown in fig. 2 as an example, the fiber to be measured does not have the faraday rotator fiber to be measured. The invention provides an optical fiber measuring method. The optical fiber measuring method comprises the following steps:
step 1: acquiring a first relation between the length of a long arm and the length of a short arm of the interferometer by using the mixed signal;
step 2: the optical fiber to be measured is connected to a long arm in the interferometer, and a second relation between the length of the long arm and the length of the short arm of the interferometer after the optical fiber to be measured is connected is obtained by utilizing the mixing signal;
step 3: calculating the length L or refractive index n of the known optical fiber to be measured according to the first relation and the second relation 0 Refractive index n of the fiber under test 0 Or length L.
The mixing signals used in the step 1 and the step 2 are obtained by inputting one path of signal of the radio frequency signal with continuously changing frequency into the interferometer before the optical fiber to be detected is connected into the interferometer and after the optical fiber to be detected is connected into the interferometer, and then mixing the output signal of the interferometer with the other path of signal of the radio frequency signal.
In the measuring device of the present embodiment, step 1 represents a relational expression obtained before an optical fiber to be measured is connected to a long arm of an interferometer, and step 2 represents a relational expression obtained after an optical fiber to be measured is connected to a long arm of an interferometer, wherein the signal transmission process is as follows before the optical fiber to be measured is connected to the long arm of the interferometer and after the optical fiber to be measured is connected to the long arm of the interferometer:
step 21: dividing a radio frequency signal emitted by a sweep frequency signal source into a first signal RF11 and a second signal RF12 which are identical;
wherein the expressions of the first signal RF11 and the second signal RF12 are as follows:
Acos(ω 1 t) or Asin (omega) 1 t+π/2)
Wherein A represents the amplitudes of the first and second signals, ω 1 The angular frequency of the first signal and the second signal is represented, t represents time. The radio frequency signal may be a sine signal or a cosine signal, and in this embodiment, the cosine signal is taken as an example for illustration, and the derivation of the sine signal also satisfies the following procedure.
Step 22: modulating a broadband light source with the first signal;
wherein the expression of the modulated light is as follows:
I 0 +I 0 ·m·cos(ω 1 t)
wherein I is 0 Representing the light intensity, m representing the modulation degree of the modulation in the light source;
step 23: inputting the light modulated in the step 22 to an interferometer to obtain an output signal;
the expression of the output signal of step 23 is:
in this example, the michelson interferometer has a coupler splitting ratio of 0.5, and it should be understood that there is an error in the device, and the coupler splitting ratio is considered to be 0.5 within a specific error range.
Step 24: inputting the output signal of the step 23 to a photoelectric detector for DC blocking processing to obtain an output signal RF22;
the expression of the signal RF22 is:
step 25: the signal RF22 is phase-shifted to become a signal RF23;
the expression of the signal RF23 is:
step 26: mixing the signal RF23 in step 25 with the second signal RF12 to obtain a mixed signal;
wherein, the expression of the mixing signal is:
step 27: filtering the mixed signal by a filtering module to obtain an output signal, and inputting the output signal to a sampling module:
wherein, the expression of the output signal of step 27 is:
in one aspect, the following equation is satisfied before accessing the fiber under test:
before further accessing the fiber under test, the output signal of step 27 may be expressed as:
0.5·I 0 ·m·A·cos((ω 1 ·n·l 1 )/c-(ω 1 ·n·l 2 )/c)
at the frequency omega of the radio frequency signal 1 When the frequency of the radio frequency signal corresponding to the minimum point of the two electric signal powers detected by the sampling module is changed, the frequency of the radio frequency signal meets a third relational expression, and the third relational expression is as follows:
(ω 11 ·n·l 1 )/c-(ω 11 ·n·l 2 )/c＝2π+(ω 12 ·n·l 1 )/c-(ω 12 ·n·l 2 )/c
ω 11 ＝2πf 11
ω 12 ＝2πf 12
ω 11 and omega 12 Is the angular frequency of the radio frequency signal corresponding to the minimum point of the power of the two electrical signals detected by the sampling module before being connected with the optical fiber to be detected, f 11 And f 12 Radio frequency corresponding to minimum point of two electric signal power measured by sampling module before accessing optical fiber to be measuredThe frequency of the signal.
Therefore, a first relation between the length of the long arm and the length of the short arm of the interferometer is obtained according to the third relation before the optical fiber to be measured is accessed, and the obtained first relation is as follows:
wherein l 1 Indicating the length of the interferometer long arm without accessing the fiber to be measured, l 2 The length of the interferometer short arm is represented, c is the speed of light in vacuum, and n is the refractive index of the interferometer fiber.
On the other hand, when the optical fiber AB to be measured is connected into the long arm of the Michelson interferometer, the following equation is satisfied:
wherein L represents the length of the optical fiber to be measured, n 0 Indicating the refractive index of the fiber under test.
After further accessing the fiber under test, the output signal of step 27 may be expressed as:
0.5·I 0 ·m·A·cos(ω 1 (n·l 1 +n 0 ·L)/c-(ω 1 ·n·l 2 )/c)
at the frequency omega of the radio frequency signal 1 When the frequency of the radio frequency signal corresponding to the minimum point of the two electric signal powers detected by the sampling module is changed, the frequency of the radio frequency signal corresponding to the minimum point of the two electric signal powers meets a fourth relational expression, and the fourth relational expression is as follows:
ω 21 (n·l 1 +n 0 ·L)/c-(ω 21 ·n·l 2 )/c＝2π+ω 22 (n·l 1 +n 0 ·L)/c-(ω 22 ·n·l 2 )/c
ω 21 ＝2πf 21
ω 22 ＝2πf 22
ω 21 and omega 22 Is the angular frequency of the radio frequency signal corresponding to the minimum point of the power of the two electrical signals detected by the sampling module after being connected with the optical fiber to be detected, f 21 And f 22 The frequency of the radio frequency signal corresponding to the minimum point of the power of the two electric signals measured by the sampling module when the radio frequency signal is modulated after the optical fiber to be measured is accessed. It should be understood that the sampling module in this embodiment is an AD sampler.
Therefore, after the optical fiber to be measured is accessed according to the fourth relation, a second relation between the length of the long arm and the length of the short arm of the interferometer accessed with the optical fiber to be measured is obtained, and the obtained second relation is as follows:
deducing the refractive index n of the known optical fiber to be measured according to the first relational expression and the second relational expression 0 When the length L of the optical fiber to be measured is calculated as follows:
when the length L of the optical fiber to be measured is known, the refractive index n of the optical fiber to be measured is obtained 0 The calculation formula of (2) is as follows:
it will be appreciated that if the refractive index n of the optical fiber under test is known 0 The length L of the optical fiber to be measured can be calculated by using the method; knowing the length L of the optical fiber to be measured, the refractive index n of the optical fiber to be measured can be calculated by the method 0 。
In addition, the sweep step Δf of the sweep signal source is determined by the minimum required arm length difference of the michelson fiber optic interferometer, and the corresponding relationship is as follows:
Δf＝150/((l 1 -l 2 )×n)MHz
the sweep step delta f of the sweep signal source is used as a reference parameter in the design process.
It should be noted that, in this embodiment, the optical fiber to be measured may be a common optical fiber, or may be a faraday rotator mirror pigtail, which is not specifically limited in the present invention.
It should be emphasized that the examples described herein are illustrative rather than limiting, and that this invention is not limited to the examples described in the specific embodiments, but is capable of other embodiments in accordance with the teachings of the present invention, as long as they do not depart from the spirit and scope of the invention, whether modified or substituted, and still fall within the scope of the invention.
Claims (10)
1. An optical fiber measurement method is characterized in that: the method comprises the following steps:
step 1: acquiring a first relation between the length of a long arm and the length of a short arm of the interferometer by using the mixed signal;
the first relation expression shows the relation between the length of the long arm and the length of the short arm of the interferometer and the difference between two frequencies which are different by one period in the radio frequency signal before the interferometer is connected to the optical fiber to be measured;
step 2: the optical fiber to be measured is connected to a long arm in the interferometer, and a second relation between the length of the long arm and the length of the short arm of the interferometer after the optical fiber to be measured is connected is obtained by utilizing the mixing signal;
the second relation expression shows the relation between the length of the long arm and the short arm of the interferometer and the difference between two frequencies which are different by one period in the radio frequency signal after the long arm of the interferometer is connected with the optical fiber to be measured;
step 3: calculating the length L or refractive index n of the known optical fiber to be measured according to the first relation and the second relation 0 Refractive index n of the fiber under test 0 Or length L;
the frequency mixing signals used in the step 1 and the step 2 are obtained by inputting one path of signal of the radio frequency signal with continuously changing frequency into the interferometer before the optical fiber to be detected is connected into the interferometer and after the optical fiber to be detected is connected into the interferometer, and then carrying out frequency mixing processing on the output signal of the interferometer and the other path of signal of the radio frequency signal;
the signal transmission process in the step 1 and the step 2 is as follows:
extracting radio frequency signals with continuously-changed frequency emitted by a sweep frequency signal source into two identical paths of signals, wherein the two identical paths of signals are a first signal and a second signal, modulating a broadband light source by utilizing the first signal and inputting the first signal into an interferometer, mixing an output signal of the interferometer with the second signal after DC blocking and phase shifting treatment, and transmitting the mixed signal to an acquisition module after filtering treatment, wherein the acquisition module acquires an electric signal power minimum point in each of two continuous periods in monitored electric signal power data in the frequency change process of the radio frequency signals, and acquires the frequency of the radio frequency signal corresponding to the two electric signal power minimum points;
the method comprises the steps of acquiring two radio frequency signals corresponding to the minimum point of the power of the two electric signals by an acquisition module, wherein the two frequencies are separated by a period, and calculating a relation between the length of a long arm and the length of a short arm of an interferometer by using the frequencies acquired by the acquisition module and the input signals of the acquisition module.
2. The method of claim 1, wherein when the period of the radio frequency signal is 2Ω, the first relationship is as follows:
the second relation is as follows:
obtaining the refractive index n of the known optical fiber to be tested 0 When the length L of the optical fiber to be measured is calculated as follows:
when the length L of the optical fiber to be measured is known, the refractive index n of the optical fiber to be measured is obtained 0 The calculation formula of (2) is as follows:
wherein l 1 Indicating the length of the interferometer long arm without accessing the fiber to be measured, l 2 Representing the length of the interferometer short arm, c is the speed of light in vacuum, n is the refractive index of the interferometer fiber, f 11 And f 12 The method comprises the steps that 1, the frequency of a radio frequency signal corresponding to the minimum point of two electric signal power measured by an acquisition module when the radio frequency signal is changed is obtained; f (f) 21 And f 22 And 2, the frequency of the radio frequency signal corresponding to the minimum point of the two electric signal powers measured by the acquisition module when the radio frequency signal changes in the step 2.
3. The method according to claim 1, characterized in that: the radio frequency signal is a cosine signal or a sine signal.
4. A method according to claim 3, characterized in that: the signal transmission process in the step 1 and the step 2 comprises the following steps:
step 21: dividing a radio frequency signal emitted by a sweep frequency signal source into a first signal RF11 and a second signal RF12 which are identical;
wherein the expressions of the first signal RF11 and the second signal RF12 are as follows:
Acos(ω 1 t) or Asin (omega) 1 t+π/2)
Wherein A represents the amplitudes of the first and second signals, ω 1 The angular frequency of the first signal and the second signal, t representing time;
step 22: modulating a broadband light source with the first signal;
wherein the expression of the modulated light is as follows:
I 0 +I 0 ·m·cos(ω 1 t)
wherein I is 0 The light intensity is represented, and m represents the modulation degree of light source modulation;
step 23: inputting the light modulated in the step 22 to an interferometer to obtain an output signal;
the expression of the output signal of step 23 is:
step 24: inputting the output signal of the step 23 to a photoelectric detector for DC blocking processing to obtain an output signal RF22;
the expression of the signal RF22 is:
step 25: the signal RF22 is phase-shifted to become a signal RF23;
the expression of the signal RF23 is:
step 26: mixing the signal RF23 in step 25 with the second signal RF12 to obtain a mixed signal;
wherein, the expression of the mixing signal is:
step 27: filtering the mixed signal by a filtering module to obtain an output signal, and inputting the output signal to an AD sampler:
wherein, the expression of the output signal of step 27 is:
wherein, the signal in step 1 satisfies:
the signal in step 3 satisfies:
wherein l 1 Indicating the length of the interferometer long arm without accessing the fiber to be measured, l 2 The length of the interferometer short arm is represented, c is the speed of light in vacuum, and n is the refractive index of the interferometer fiber.
5. The method according to claim 4, wherein: according to the output signal of the step 27, the frequency of the radio frequency signal corresponding to the minimum point of the two electric signal powers detected by the acquisition module in the step 1 meets a third relational expression;
wherein the third relation is as follows:
(ω 11 ·n·l 1 )/c-(ω 11 ·n·l 2 )/c＝2π+(ω 12 ·n·l 1 )/c-(ω 12 ·n·l 2 )/c
ω 11 ＝2πf 11
ω 12 ＝2πf 12
ω 11 and omega 12 The method comprises the steps that 1, the angular frequency of a radio frequency signal corresponding to the minimum point of two electric signal powers detected by an acquisition module is obtained;
according to the output signal of the step 27, the frequency of the radio frequency signal corresponding to the minimum point of the two electric signal powers detected by the acquisition module in the step 2 meets a fourth relational expression;
wherein the fourth relation is as follows:
ω 21 (n·l 1 +n 0 ·L)/c-(ω 21 ·n·l 2 )/c＝2π+ω 22 (n·l 1 +n 0 ·L)/c-(ω 22 ·n·l 2 )/c
ω 21 ＝2πf 21
ω 22 ＝2πf 22
ω 21 and omega 22 The angular frequency of the radio frequency signal corresponding to the minimum point of the two electric signal powers detected by the acquisition module in the step 2;
f 11 and f 12 The method comprises the steps that 1, the frequency of a radio frequency signal corresponding to the minimum point of two electric signal power measured by an acquisition module when the radio frequency signal is changed is obtained; f (f) 21 And f 22 And 2, the frequency of the radio frequency signal corresponding to the minimum point of the two electric signal powers measured by the acquisition module when the radio frequency signal changes in the step 2.
6. The method according to claim 1, characterized in that: the optical fiber to be measured is a Faraday rotator mirror tail optical fiber.
7. An optical fiber measuring device, characterized in that: comprising the following steps: the device comprises a light source module, a sweep frequency signal source, a power divider, an interferometer, a photoelectric detector, a phase shifting module, a mixing module, a filtering module, an AD sampler and a measurement processor;
the power divider is used for extracting radio frequency signals with continuously changing frequencies of the sweep frequency signal source into two identical paths of signals, wherein the two paths of signals are a first signal and a second signal;
one end of the power divider is connected with the light source module, the other end of the power divider is connected with the frequency mixing module, the first signal is transmitted to the light source module to modulate a broadband light source of the light source module, and the second signal is transmitted to the frequency mixing module;
the light source module, the interferometer, the photoelectric detector, the phase shifting module and the mixing module are sequentially connected;
the light source module is used for transmitting the modulated light signals to the interferometer, the photoelectric detector is used for performing direct current blocking processing on the output signals of the interferometer, the phase shifting module is used for performing phase shifting processing on the output signals of the photoelectric detector, and transmitting the signals after the phase shifting processing to the mixing module;
the mixing module, the filtering module, the AD sampler and the measurement processor are sequentially connected;
the frequency mixing module is used for carrying out frequency mixing processing on the second signal and the output signal of the phase shifting module;
the filtering module is used for filtering high-frequency components in the mixed signals and transmitting the high-frequency components to the AD sampler;
the AD sampler is used for acquiring an electric signal power minimum point in each of two continuous periods in the monitored electric signal power data in the frequency change process of the radio frequency signal, and acquiring the frequency of the radio frequency signal corresponding to the two electric signal power minimum points; the measuring processor is used for calculating a relation between a long arm and a short arm of the interferometer according to the frequency of the radio frequency signal acquired by the AD sampler;
wherein, the two frequencies of the radio frequency signal corresponding to the minimum point of the two electric signal powers obtained by the AD sampler are separated by a period;
before a long arm of the interferometer is connected with an optical fiber to be measured, the measurement processor obtains a first relation between the length of the long arm and the length of the short arm of the interferometer according to the frequency change of a radio frequency signal of a sweep frequency signal source;
the first relation expression shows the relation between the length of the long arm and the length of the short arm of the interferometer and the difference between the two frequencies of the radio frequency signals acquired by the AD sampler before the optical fiber to be detected is accessed;
after the long arm of the interferometer is connected with the optical fiber to be measured, the measurement processor obtains a second relation between the length of the long arm and the length of the short arm of the interferometer connected with the optical fiber to be measured according to the frequency change of the radio frequency signal of the sweep frequency signal source;
the second relation represents the relation between the length of the long arm and the short arm of the interferometer and the difference between the two frequencies of the radio frequency signals acquired by the AD sampler after the long arm of the interferometer is connected with the optical fiber to be detected;
the measurement processor is used for calculating the length L or the refractive index n of the known optical fiber to be measured according to the first relational expression and the second relational expression 0 Refractive index n of the fiber under test 0 Or length L.
8. The apparatus according to claim 7, wherein: the light source module comprises a broadband light source and a modulator;
the broadband light source is connected with the modulator, the power divider and the interferometer are connected with the modulator, and the modulator is used for modulating the intensity of the broadband light source by using the first signal.
9. The apparatus according to claim 8, wherein: the modulator is any one of an electro-optical modulator, an acousto-optic modulator and a mechanical chopper.
10. The apparatus according to claim 7, wherein: the light source module comprises a direct current power supply and a broadband light source;
the power divider and the interferometer are connected with the broadband light source, and the DC power supply provides bias current for the broadband light source.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711156962.6A CN108007307B (en) | 2017-11-20 | 2017-11-20 | Optical fiber measuring method and measuring device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711156962.6A CN108007307B (en) | 2017-11-20 | 2017-11-20 | Optical fiber measuring method and measuring device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108007307A CN108007307A (en) | 2018-05-08 |
| CN108007307B true CN108007307B (en) | 2024-03-29 |
Family
ID=62052795
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201711156962.6A Active CN108007307B (en) | 2017-11-20 | 2017-11-20 | Optical fiber measuring method and measuring device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108007307B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112769471B (en) * | 2019-11-01 | 2022-08-26 | 华为技术有限公司 | Optical fiber testing method based on optical time domain reflectometer and optical time domain reflectometer |
| CN110849586B (en) * | 2019-11-25 | 2020-11-24 | 南京航空航天大学 | Optical fiber interferometer parameter measurement method and device |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005241298A (en) * | 2004-02-24 | 2005-09-08 | Oki Electric Ind Co Ltd | Interference type optical fiber sensor |
| TW201022629A (en) * | 2008-12-15 | 2010-06-16 | Nxtar Technologies Inc | For path imbalance measurement of the two arms fiber optic interferomter |
| CN104092538A (en) * | 2014-07-15 | 2014-10-08 | 华南师范大学 | Multi-user wavelength division multiplexing QKD network system and secret key distributing and sharing method thereof |
| CN104330104A (en) * | 2014-10-31 | 2015-02-04 | 浙江大学 | Measuring device for interferential sensor arm length difference |
| CN105043526A (en) * | 2015-05-27 | 2015-11-11 | 浙江大学 | Vibration sensing device based on photoelectric oscillator |
| CN106969714A (en) * | 2017-05-02 | 2017-07-21 | 中国航空工业集团公司北京长城计量测试技术研究所 | A kind of method of the fine length of precise measuring |
| CN107255440A (en) * | 2017-07-28 | 2017-10-17 | 浙江九州量子信息技术股份有限公司 | A kind of signal contrast formula laser phase self feed back interferometer and self feed back interference technique |
-
2017
- 2017-11-20 CN CN201711156962.6A patent/CN108007307B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005241298A (en) * | 2004-02-24 | 2005-09-08 | Oki Electric Ind Co Ltd | Interference type optical fiber sensor |
| TW201022629A (en) * | 2008-12-15 | 2010-06-16 | Nxtar Technologies Inc | For path imbalance measurement of the two arms fiber optic interferomter |
| CN104092538A (en) * | 2014-07-15 | 2014-10-08 | 华南师范大学 | Multi-user wavelength division multiplexing QKD network system and secret key distributing and sharing method thereof |
| CN104330104A (en) * | 2014-10-31 | 2015-02-04 | 浙江大学 | Measuring device for interferential sensor arm length difference |
| CN105043526A (en) * | 2015-05-27 | 2015-11-11 | 浙江大学 | Vibration sensing device based on photoelectric oscillator |
| CN106969714A (en) * | 2017-05-02 | 2017-07-21 | 中国航空工业集团公司北京长城计量测试技术研究所 | A kind of method of the fine length of precise measuring |
| CN107255440A (en) * | 2017-07-28 | 2017-10-17 | 浙江九州量子信息技术股份有限公司 | A kind of signal contrast formula laser phase self feed back interferometer and self feed back interference technique |
Also Published As
| Publication number | Publication date |
|---|---|
| CN108007307A (en) | 2018-05-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110411335B (en) | Differential sine phase modulation laser interference nano displacement measuring device and method | |
| JP3667132B2 (en) | Brillouin gain spectrum measurement method and apparatus | |
| US5268741A (en) | Method and apparatus for calibrating a polarization independent optical coherence domain reflectometer | |
| Norgia et al. | Self-mixing instrument for simultaneous distance and speed measurement | |
| CN108827601A (en) | A kind of measuring device of fibre optic interferometer arm length difference | |
| CN104330104B (en) | Measuring device for interferential sensor arm length difference | |
| CN108801153B (en) | Optical fiber length measuring method and measuring device | |
| CN101949685B (en) | Fiber laser self-mixing interferometer and measurement method thereof | |
| CN106643522A (en) | Optical-fiber low-coherence interference displacement demodulation device and method based on photoelectric oscillator | |
| US20160245719A1 (en) | Optical pulse compression reflectometer | |
| CN112129491B (en) | Optical fiber time delay measuring method and device based on single-optical-frequency comb interference | |
| JP7239975B2 (en) | Optical angle modulation measuring device and measuring method | |
| WO2021082377A1 (en) | Phase derivation-based optical component delay measurement method, and device | |
| CN108844717A (en) | A kind of measurement method of fibre optic interferometer arm length difference | |
| Li et al. | High-resolution frequency-modulated continuous-wave LiDAR using multiple laser sources simultaneously scanning | |
| CN108007307B (en) | Optical fiber measuring method and measuring device | |
| CN111912516A (en) | Phase-synchronized optical fiber distributed vibration measurement device, driver and method | |
| CN109031341B (en) | Object movement speed measuring method using continuous frequency modulation laser radar device | |
| Minoni et al. | A high‐frequency sinusoidal phase‐modulation interferometer using an electro‐optic modulator: Development and evaluation | |
| CN115752416A (en) | Resonant fiber optic gyroscope for detecting angular velocity signals | |
| CN112187347B (en) | Device and method for measuring length of optical fiber | |
| CN110849586B (en) | Optical fiber interferometer parameter measurement method and device | |
| CN213455339U (en) | Device for measuring optical fiber length | |
| CN112187345B (en) | Device and method for measuring length of optical fiber | |
| CN212254333U (en) | Phase synchronization optical fiber distributed vibration measuring device and driver |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| CB02 | Change of applicant information | ||
| CB02 | Change of applicant information |
Address after: 410100 5 East three road, Changsha economic and Technological Development Zone, Changsha, Hunan Applicant after: CHANGSHA HCC HIDEN TECHNOLOGY Co.,Ltd. Applicant after: HUNAN GREAT WALL HAIDUN FIBER TECHNOLOGY Co.,Ltd. Address before: 410100 5 East three road, Changsha economic and Technological Development Zone, Changsha, Hunan Applicant before: CHANGSHA HCC HIDEN TECHNOLOGY Co.,Ltd. Applicant before: HUNAN HAIDUN OPTICAL FIBER SENSING TECHNOLOGY ENGINEERING LABORATORY Co.,Ltd. |
|
| TA01 | Transfer of patent application right | ||
| TA01 | Transfer of patent application right |
Effective date of registration: 20181121 Address after: 410205 No. A076, Headquarters Building of Zhongdian Software Park, 39 Jianshan Road, Changsha High-tech Development Zone, Changsha City, Hunan Province Applicant after: HUNAN GREAT WALL HAIDUN FIBER TECHNOLOGY Co.,Ltd. Address before: 410100 5 East three road, Changsha economic and Technological Development Zone, Changsha, Hunan Applicant before: CHANGSHA HCC HIDEN TECHNOLOGY Co.,Ltd. Applicant before: HUNAN GREAT WALL HAIDUN FIBER TECHNOLOGY Co.,Ltd. |
|
| GR01 | Patent grant | ||
| GR01 | Patent grant |