CN105891801B - Multiple-harmonic heterodyne locks the device of field widening Michelson's interferometer - Google Patents
Multiple-harmonic heterodyne locks the device of field widening Michelson's interferometer Download PDFInfo
- Publication number
- CN105891801B CN105891801B CN201610216993.5A CN201610216993A CN105891801B CN 105891801 B CN105891801 B CN 105891801B CN 201610216993 A CN201610216993 A CN 201610216993A CN 105891801 B CN105891801 B CN 105891801B
- Authority
- CN
- China
- Prior art keywords
- signal
- fwmi
- frequency
- photodetector
- laser
- 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
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/48—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S17/00
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Lasers (AREA)
Abstract
The invention discloses a kind of device of multiple-harmonic heterodyne locking field widening Michelson's interferometer.The present invention such as produces at the multi resonant wave component of frequency spacing by way of phase-modulation, and after being modulated by FWMI transmittance functions heterodyne process occurs for these harmonic components, so as to generate the feedback signal of reflection FWMI resonant frequency drift size and Orientation information.Under the continuous effect of feedback control, the resonant frequency of FWMI can tend to filters center frequency and settle out, and at this moment feedback control signal will be returned to 0, so as to complete Frequency Locking.The present invention can compensate because the FWMI resonant frequencies drift that the reason such as environment temperature is brought automatically, and locking precision is high, locking process is intelligently rapid, the high stable for being FWMI spectral filters in HSRL operation creates basic guarantee, has to the precision for improving HSRL Atmospheric Surveys and greatly facilitates effect.
Description
Technical field
The invention belongs to laser radar technique field, and field widening Michael is locked more particularly to a kind of multiple-harmonic heterodyne
The device of inferior interferometer.
Background technology
High spectral resolution lidar (HSRL) technology is at present to effective hand of atmospheric aerosol optical parameter remote sensing
Section.HSRL technologies need to be dissipated by the Mie scattering in the filter separation Received Signal with high spectral resolution ability and Rayleigh
Component is penetrated to realize.Recently, a kind of new spectral filter --- field widening Michelson's interferometer (FWMI) is invented
And for completing the spectrum separation function in HSRL systems.FWMI is substantially a kind of improved Michelson's interferometer (MI),
Its essential reason with spectrum separation function is the frequency dependence because the interference of light.In order to preferably complete the spectrum work of separation
Can, its resonant frequency must accurately be maintained at the centre wavelength of HSRL lasers when FWMI works in HSRL.Although it can lead to
Manual mode piezo-ceramic micro displacement unit (PZT) is crossed by the resonant frequency harmony of FWMI to laser frequency, still, due to reality
The change of environment temperature, air pressure etc., can cause the change of FWMI optical path differences when border operates, its final resonant frequency also with
And drift about.The method being readily apparent that is FWMI to be placed in a high closed box of temperature stability to keep its resonance
Frequency from environmental turbulence influence.But theory analysis shows, the temperature stability of the temperature control box should at 0.001 degree Celsius or
Higher can just be met the requirements.This is a huge challenge for domestic current temperature control technology.Therefore, how by FWMI
It is problem urgently to be resolved hurrily at present that resonant frequency, which is stably locked at filters center frequency,.
The content of the invention
The purpose of the present invention is overcome above-mentioned difficult point, it is proposed that is filtered using multiple-harmonic heterodyne technology real-time lock FWMI spectrum
Light device resonant frequency to filters center frequency device.
The technical solution adopted by the present invention to solve the technical problems is as follows：
Multiple-harmonic heterodyne lock field widening Michelson's interferometer device, including laser, electro-optic phase modulator,
Signal generator, laser beam expander, Amici prism, the first lens, the first photodetector, the second lens, the second photodetection
Device, FWMI main bodys a, electronic system module b and control computer；
Electronic system module b includes the first multiplier, the second multiplier, 90-degree phase shifter, the first low-pass filter, second
Low-pass filter and data collecting card；
Reference of the continuous laser of laser transmitting as Frequency Locking, first continuous laser pass through electro-optic phase modulator
Modulation after produce multiple-harmonic sideband laser signal, wherein, the drive signal of electro-optic phase modulator is provided by signal generator；
The multiple-harmonic sideband laser signal modulated enters FWMI main bodys a after laser beam expander expands further through Amici prism；
Laser signal after FWMI main bodys a can produce two-way output, wherein the signal reflected is by light splitting rib
Mirror after secondary reflection, is converged on the first photodetector by the first lens again, and concurrent third contact of a total solar or lunar eclipse heterodyne process is so as to generate many frequencies
The voltage signal of rate mixing；And the signal for passing through FWMI main bodys a is then converged on the second photodetector by the second lens, due to
The second photodetector speed of response does not catch up with the change of heterodyne signal much, therefore only serves common DC energy detection work(
Energy.
The output electric signal of first photodetector and the drive signal of signal generator are (with driving electric light phase-modulation
The signal of device is identical) it is processed in electronic system module b：A signal generator signal part by after 90-degree phase shifter phase shift and
The output electric signal of first photodetector is multiplied, which is completed by the first multiplier.The result of product signal is by
Recorded after the filtering of one low-pass filter by data collecting card, be known as quadrature signal component；Another portion of signal generator signal
Divide and be directly multiplied with the output electric signal of the first photodetector, which is completed by the second multiplier.Product signal
As a result recorded after being filtered by the second low-pass filter by data collecting card, be known as inphase signal component.Quadrature signal component
Control computer is admitted to inphase signal component, control computer is conveyed to using one feedback control amount of the two signal generations
The frequency modulation equipment (such as piezoelectric ceramics, gas pressure regulator, different and different depending on FWMI structures) of FWMI main bodys a.Feedback control amount
Generating formula is
Wherein, F represents feedback control amount, and P represents quadrature signal component, and I represents inphase signal component.The feedback control amount
It is related with the drift degree of FWMI resonant frequencies and direction, when FWMI resonant frequencies are floated relative to laser frequency toward positive direction
During shifting, which is on the occasion of and size is proportional to frequency drift amount；Conversely, then the feedback control amount is negative value, size
Also proportional to frequency drift amount.Under the continuous effect of feedback control, the resonant frequency of FWMI can tend to filters center frequency
And settle out, at this moment feedback control signal will be returned to 0, so as to complete Frequency Locking.
Need to select two running parameters, i.e. modulation depth and modulating frequency when electro-optic phase modulator works.At this
In scheme, optimal modulation depth is 3rad, and modulating frequency is 0.1 × FSR, and wherein FSR is the free spectrum of FWMI to be locked
Scope.The bandwidth of first photodetector should be greater than the modulating frequency equal to 2 times；Second photodetector is
Common energy-probe, bandwidth are generally hundreds of and arrive thousands of Hz.First low-pass filter and the second low pass filtered
The cutoff frequency of ripple device is generally less than 5MHz.
The present invention has the beneficial effect that：
The present invention is by the way of the control of multiple-harmonic heterodyne active feedback by FWMI resonant frequencies steady lock to laser
Centre wavelength, can compensate because the frequency drift that the reason such as environment temperature is brought, system lock precision is high, locking process intelligence automatically
Can be rapid, it is that high stable operation of the FWMI spectral filters in HSRL creates basic guarantee, to improving HSRL Atmospheric Surveys
Precision have greatly facilitate effect.
Brief description of the drawings
Fig. 1 apparatus of the present invention schematic diagrames；
Fig. 2 is the multi resonant wave component produced after laser is modulated by electro-optic phase modulator；
Fig. 3 be FWMI resonant frequencies from drifting state to lock-out state when feedback control signal an example；
Fig. 4 is the output signal of the second photodetector when FWMI is in locking.
In figure, laser 1, electro-optic phase modulator 2, signal generator 3, laser beam expander 4, Amici prism 5, first are saturating
Mirror 6, the first photodetector 7, the second lens 8, the second photodetector 9, FWMI main bodys a, electronic system module b and control
Computer 10；
Electronic system module b includes the first multiplier 11, the second multiplier 12,90-degree phase shifter 13, the first low-pass filtering
Device 14, the second low-pass filter 15 and data collecting card 16.
Embodiment
The invention will be further described below in conjunction with the accompanying drawings.
As shown in Figure 1, the device of multiple-harmonic heterodyne locking field widening Michelson's interferometer, including laser 1, electric light
Phase-modulator 2, signal generator 3, laser beam expander 4, Amici prism 5, the first lens 6, the first photodetector 7, second
Lens 8, the second photodetector 9, FWMI main bodys a, electronic system module b and control computer 10；
Electronic system module b includes the first multiplier 11, the second multiplier 12,90-degree phase shifter 13, the first low-pass filtering
Device 14, the second low-pass filter 15 and data collecting card 16；
Reference of the continuous laser that laser 1 is launched as Frequency Locking, first continuous laser pass through electric light phase-modulation
Multiple-harmonic sideband laser signal is produced after the modulation of device 2, wherein, the drive signal of electro-optic phase modulator 2 is by signal generator 3
There is provided；The multiple-harmonic sideband laser signal modulated enters FWMI master after laser beam expander 4 expands further through Amici prism 5
Body a；
Laser signal after FWMI main bodys a can produce two-way output, wherein the signal reflected is by light splitting rib
Mirror 5 after secondary reflection, is converged on the first photodetector 7 by the first lens 6 again, and concurrent third contact of a total solar or lunar eclipse heterodyne process is corresponding so as to generate
The voltage signal of frequency；And the signal for passing through FWMI main bodys a is then converged on the second photodetector 9 by the second lens 8, due to
Second photodetector, 9 speed of response does not catch up with the change of heterodyne signal much, therefore only serves common DC energy detection work(
Energy.
The output electric signal of first photodetector 7 and the drive signal of signal generator 3 are (with driving electric light phase tune
The signal of device 2 processed is identical) it is processed in electronic system module b：A drive signal part for signal generator 3 is by 90 degree of phase shifts
Output electric signal after 13 phase shift of device with the first photodetector 7 is multiplied, which is completed by multiplier 11.Product signal
Result filtered by the first low-pass filter 14 after recorded by data collecting card 16, be known as quadrature signal component.Signal is sent out
Drive signal another part of raw device 3 is directly multiplied with the output electric signal of the first photodetector 7, and the multiplication processes are by multiplication
Device 12 is completed.The result of product signal is recorded after being filtered by the second low-pass filter 15 by data collecting card 16, is known as same
Phase signal component.Quadrature signal component and inphase signal component are admitted to control computer 10, and control computer 10 utilizes the two letters
Number one feedback control amount of generation is conveyed to frequency modulation equipment (such as piezoelectric ceramics, gas pressure regulator, depending on FWMI of FWMI main bodys a
Structure is different and different).The generation formula of feedback control amount is
Wherein, F represents feedback control amount, and P represents quadrature signal component, and I represents inphase signal component.The feedback control amount
It is related with the drift degree of FWMI resonant frequencies and direction, when FWMI resonant frequencies are floated relative to laser frequency toward positive direction
During shifting, which is on the occasion of and size is proportional to frequency drift amount；Conversely, the feedback control amount is negative value, size
It is proportional to frequency drift amount.Under the continuous effect of feedback control, the resonant frequency of FWMI can tend to filters center frequency simultaneously
Settle out, at this moment feedback control signal will be returned to 0, so as to complete Frequency Locking.
Need to select two running parameters, i.e. modulation depth and modulating frequency when electro-optic phase modulator 2 works.At this
In scheme, optimal modulation depth is 3rad, and modulating frequency is 0.1 × FSR, and wherein FSR is the free spectrum model of FWMI to be locked
Enclose.The bandwidth of first photodetector should be greater than the modulating frequency equal to 2 times；Second photodetector 9 is
Common energy-probe, bandwidth are generally hundreds of and arrive thousands of Hz.First low-pass filter 11 and the second low pass
The cutoff frequency of wave filter 12 is generally less than 5MHz.
For the present invention using the feedback signal of multiple-harmonic infradyne manner generation control FWMI, feedback signal can be from motion tracking FWMI
The direction of resonant frequency drift and size, so that FWMI resonant frequencies to be locked to the centre frequency of laser automatically.The locking
Scheme high sensitivity, locking time are short, locking precision is high, are to ensure FWMI for a long time steady operation is most in HSRL systems
One of good mode.
Embodiment
In Fig. 1, laser 1 is the continuous laser identical with HSRL main laser wavelength；Electro-optic phase modulator 2 is niobic acid
Lithium high speed electro-optical phase-modulator, such as the 4003NF phase-modulator modules of Newport companies；Signal generator 3 is common more
Function signal generator, such as safe and sound letter GA1484A；Laser beam expander 4 can select Beijing Daheng GCO-140121；Amici prism
5 be common unpolarized Amici prism, such as Beijing Daheng GCC-401052；First lens 6 and the second lens 8 are saturating for common convergence
Mirror, focal length unrestricted choice as required, such as Beijing Daheng GCL-010111B, focal length 100mm；First photodetector 7 is at a high speed
Photodetector, such as Newport companies 818-BB-30, bandwidth 2GHz；Second photodetector 9 is visited for common energy photoelectricity
Device is surveyed, such as thorlabs companies FDPS3X3.Control computer 10 selects any commercial computer.
FMWI main bodys a to be measured is the interferometer for needing to lock, its FSR is 2GHz, humorous as frequency using piezoelectric ceramics
Adjust device.
In electronic system module b, the first multiplier 11 and the second multiplier 12 and 90-degree phase shifter 13 are in LINEAR
Have in the chip LTC5584 of TECHNOLOGY companies production integrated；First low-pass filter 14, the second low-pass filter 15 use
The LT1568 chips of LINEAR TECHNOLOGY companies are completed；Data collecting card 16 is 9220 data acquisition modules of NI companies NI
Block.
The characteristics of multiple-harmonic heterodyne locks FWMI devices is further illustrated with reference to specific device parameter.
Fig. 2 shown under conditions of selected phase-modulator parameter, the spectral distribution graph after obtained phase-modulation, its
In also give FWMI transmittance functions in the lump.It can be seen that many discrete frequencies point are occurred by modulated laser frequency spectrum
Amount, they have different amplitudes, and equidistantly arrange, these frequency contents are multi resonant wave component.These frequency component quilts
Heterodyne process occurs after the modulation of FWMI transmittance functions, so as to provide the foundation for the generation of feedback control amount.
Fig. 3 be FWMI resonant frequencies from drifting state to lock-out state when feedback control signal an example.In A points,
Locking system brings into operation, and error signal oscillation simultaneously decays rapidly, 0 is begun to return in 1s or so error signals, such as the B in figure
Shown in point.Then under the action of feedback control system, error signal stabilization is 0.It is to test locking at point C in Fig. 3
Stability and the interference that is artificially introduced (by beaing FWMI main bodys), it can be seen that under noisy condition, the system
Also it can recover stable rapidly.
Fig. 4 is the output signal of the second photodetector when FWMI is in locking.It is seen that it is in locking shape in FWMI
After state, the output signal of the second photodetector also quickly changes to 0, is locked in phase resonance-eliminating at present this illustrates FWMI
State, is exactly the required working conditions of HSRL.
Fig. 3 and Fig. 4 indicates the locking device has fabulous locking performance to FWMI.
Claims (6)
1. multiple-harmonic heterodyne locks the device of field widening Michelson's interferometer, including laser, electro-optic phase modulator, letter
Number generator, laser beam expander, Amici prism, the first lens, the first photodetector, the second lens, the second photodetector,
FWMI main bodys a, electronic system module b and control computer；
Electronic system module b includes the first multiplier, the second multiplier, 90-degree phase shifter, the first low-pass filter, the second low pass
Wave filter and data collecting card；
Reference of the continuous laser of laser transmitting as Frequency Locking, the tune that continuous laser passes through electro-optic phase modulator first
Multiple-harmonic sideband laser signal is produced after system, wherein, the drive signal of electro-optic phase modulator is provided by signal generator；Adjusted
The multiple-harmonic sideband laser signal of system enters FWMI main bodys a after laser beam expander expands further through Amici prism；
Laser signal after FWMI main bodys a can produce two-way output, wherein the signal reflected passes through Amici prism again
After secondary reflection, converged to by the first lens on the first photodetector, concurrent third contact of a total solar or lunar eclipse heterodyne process is mixed so as to generate many frequencies
The voltage signal of conjunction；And the signal for passing through FWMI main bodys a is then converged on the second photodetector by the second lens, due to second
The photodetector speed of response does not catch up with the change of heterodyne signal much, therefore only serves common DC energy detecting function；
The output electric signal of first photodetector and the drive signal of signal generator are located in electronic system module b
Reason：A drive signal part for signal generator is by the output electric signal phase after 90-degree phase shifter phase shift with the first photodetector
Multiply, which is completed by the first multiplier；The result of product signal by the first low-pass filter filter after by data acquisition
Card is recorded, and is known as quadrature signal component；Drive signal another part of signal generator is directly and the first photodetector
Output electric signal be multiplied, which is completed by the second multiplier；The result of product signal is filtered by the second low-pass filter
Recorded after ripple by data collecting card, be known as inphase signal component；Quadrature signal component and inphase signal component are admitted to control
Computer processed, control computer generate a feedback control amount using quadrature signal component and inphase signal component and are conveyed to FWMI main bodys
The frequency modulation equipment of a；The generation formula of feedback control amount is：
<mrow>
<mi>F</mi>
<mo>=</mo>
<msqrt>
<mrow>
<msup>
<mi>P</mi>
<mn>2</mn>
</msup>
<mo>+</mo>
<msup>
<mi>I</mi>
<mn>2</mn>
</msup>
</mrow>
</msqrt>
<mo>-</mo>
<mo>-</mo>
<mo>-</mo>
<mrow>
<mo>(</mo>
<mn>1</mn>
<mo>)</mo>
</mrow>
</mrow>
Wherein, F represents feedback control amount, and P represents quadrature signal component, and I represents inphase signal component；The feedback control amount with
The drift degree of FWMI resonant frequencies and direction are related, when FWMI resonant frequencies are drifted about relative to laser frequency toward positive direction
When, which is on the occasion of and size is proportional to frequency drift amount；Conversely, then the feedback control amount is negative value, size
It is proportional to frequency drift amount；Under the continuous effect of feedback control, the resonant frequency of FWMI can tend to filters center frequency simultaneously
Settle out, at this moment feedback control signal will be returned to 0, so as to complete Frequency Locking.
2. the device of multiple-harmonic heterodyne locking field widening Michelson's interferometer as claimed in claim 1, it is characterised in that
Multiple-harmonic sideband signals are produced using electro-optic phase modulator, and feedback control amount is produced using the heterodyne of more sideband signals, from
And real-time stabilization FWMI.
3. the device of multiple-harmonic heterodyne locking field widening Michelson's interferometer as claimed in claim 1, its feature is in electricity
Optical phase modulator selectes modulation depth when working be 3rad, and modulating frequency is 0.1 × FSR, and wherein FSR is FWMI's to be locked
Free Spectral Range.
4. the device of multiple-harmonic heterodyne locking field widening Michelson's interferometer as claimed in claim 3, it is characterised in that
The bandwidth of first photodetector should be greater than the modulating frequency equal to 2 times；Second photodetector is common energy
Detector, bandwidth arrive thousands of Hz for hundreds of.
5. the device of multiple-harmonic heterodyne locking field widening Michelson's interferometer as claimed in claim 1, it is characterised in that
The cutoff frequency of first low-pass filter and the second low-pass filter is less than 5MHz.
6. the device of multiple-harmonic heterodyne locking field widening Michelson's interferometer as claimed in claim 1, it is characterised in that
The device can lock any kind of Michelson's interferometer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610216993.5A CN105891801B (en) | 2016-04-07 | 2016-04-07 | Multiple-harmonic heterodyne locks the device of field widening Michelson's interferometer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610216993.5A CN105891801B (en) | 2016-04-07 | 2016-04-07 | Multiple-harmonic heterodyne locks the device of field widening Michelson's interferometer |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN105891801A CN105891801A (en) | 2016-08-24 |
| CN105891801B true CN105891801B (en) | 2018-04-20 |
Family
ID=57012502
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201610216993.5A Active CN105891801B (en) | 2016-04-07 | 2016-04-07 | Multiple-harmonic heterodyne locks the device of field widening Michelson's interferometer |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN105891801B (en) |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3577054B2 (en) * | 2002-03-27 | 2004-10-13 | ローム株式会社 | Optical pickup, optical pickup manufacturing method, and optical disk system |
| CN1869658A (en) * | 2006-06-13 | 2006-11-29 | 中国科学院安徽光学精密机械研究所 | Interferometer of space heterodyne spectrograph tester |
| WO2014190027A1 (en) * | 2013-05-22 | 2014-11-27 | Massachusetts Institute Of Technology | Methods, systems, and apparatus for imaging spectroscopy |
| CN103308926B (en) * | 2013-06-18 | 2015-07-22 | 浙江大学 | Laser radar set with high spectral resolution |
| CN103809166B (en) * | 2014-01-20 | 2016-08-17 | 浙江大学 | A kind of Michelson interference type spectral filter resonant frequency locking device and method |
| CN104777472B (en) * | 2015-03-13 | 2017-03-01 | 浙江大学 | A kind of FWMI spectral filter adjustment and performance testing device and method |
| CN104880244B (en) * | 2015-06-12 | 2017-11-10 | 哈尔滨工业大学 | The Michelson heterodyne laser vialog being divided based on monophone light modulation and depolarization |
-
2016
- 2016-04-07 CN CN201610216993.5A patent/CN105891801B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN105891801A (en) | 2016-08-24 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN105576478B (en) | The Fourier mode locking optical-electronic oscillator of rapid frequency-sweeping | |
| US9689772B2 (en) | Optical pulse compression reflectometer | |
| CN108761437B (en) | Microwave photon full polarization radar detection method and microwave photon full polarization radar | |
| CN108933379A (en) | Laser frequency-offset-lock system | |
| KR102453813B1 (en) | Light comb generating device and spectrometers comprising the same | |
| CN109375230B (en) | High-precision laser echo frequency modulation system and method | |
| CN106025787A (en) | Femtosecond laser carrier envelope offset frequency lock system based on heterodyne interferometric method | |
| CN108303704B (en) | Laser measurement method based on polarization modulation and laser radar | |
| Vu et al. | Accurate displacement-measuring interferometer with wide range using an I2 frequency-stabilized laser diode based on sinusoidal frequency modulation | |
| CN103684450A (en) | Method for outputting standard frequency of coherent population beat-frequency atomic clock | |
| CN108885138A (en) | The measuring method for waveform and waveform meter of pulsed light | |
| CN105005051A (en) | Single-optical-path laser distance measuring system | |
| US11255969B2 (en) | Measurement apparatus and measurement method | |
| CN115494479A (en) | Single photon radar system based on pulse sequence extraction and 3D imaging method | |
| CN103809166B (en) | A kind of Michelson interference type spectral filter resonant frequency locking device and method | |
| US20230050363A1 (en) | Collaborative Phase-Shift Laser Ranging Device Based on Differential Modulation and Demodulation of Coarse and Precise Measuring Wavelength and Ranging Method Thereof | |
| CN103809167A (en) | Device and method for locking resonant frequency of FP interferometric spectrum filter | |
| CN105576495B (en) | Residual amplitude modulation stabilising arrangement based on angle of wedge electro-optic crystal | |
| CN114397670A (en) | Laser radar system and method for measuring micro Doppler of high-speed moving target | |
| CN111929663B (en) | Linear frequency modulation radar signal generation system and method | |
| CN112857591B (en) | Single laser source optical fiber laser system for cold atom interferometer | |
| Marquez et al. | Interaction between Lienard and Ikeda dynamics in a nonlinear electro-optical oscillator with delayed bandpass feedback | |
| CN105891801B (en) | Multiple-harmonic heterodyne locks the device of field widening Michelson's interferometer | |
| CN107946896B (en) | A kind of Pound-Drever-Hall laser frequency stabilizing system of heterodyne system phase-sensitive detection | |
| JP2014059247A (en) | Distance measurement method and device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |