CN104990619B - Michelson heterodyne laser vialog based on dual-acousto-optic modulation and depolarization light splitting - Google Patents
Michelson heterodyne laser vialog based on dual-acousto-optic modulation and depolarization light splitting Download PDFInfo
- Publication number
- CN104990619B CN104990619B CN201510338682.1A CN201510338682A CN104990619B CN 104990619 B CN104990619 B CN 104990619B CN 201510338682 A CN201510338682 A CN 201510338682A CN 104990619 B CN104990619 B CN 104990619B
- Authority
- CN
- China
- Prior art keywords
- light
- light beam
- acousto
- polarization
- optic modulator
- 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
Abstract
Anti-polarization aliasing Michelson heterodyne laser vialog based on dual-acousto-optic modulation and depolarization light splitting belongs to laser interferometry field；Non-polarization Beamsplitter NBS light splitting is adopted to form reference arm and measure arm, incident beam on reference arm and on measurement arm is all through acousto-optic modulator generation diffraction, the first-order diffraction light of shift frequency is turned back element adjustment by light beam, makes direction of beam propagation be parallel to incident beam；Reflection light is made to be positioned at above acousto-optic modulator by adjusting prism of corner cube, so that measuring light and reference light all only through an acousto-optic modulator, adjustment reference angle cone prism and measurement prism of corner cube make reference light and measurement light again pass by light beam coincidence during non-polarization Beamsplitter NBS, and interfere；The present invention adopts less optical element to achieve heterodyne laser interference and measures, light path adjustment is simple, can effectively solve that prior art exists polarisation leakage and adjust the problems such as complicated with polarization aliasing, light path, in ultraprecise vibration measurement field, there is significant technical advantage.
Description
Technical field
The invention belongs to laser interferometry field, relate generally to a kind of anti-polarization aliasing Michelson heterodyne laser vialog based on dual-acousto-optic modulation and depolarization light splitting.
Background technology
Laser vibration measurer, as the ultra precise measurement instrument that vibration value can be traceable to optical maser wavelength, is widely used in the fields such as displacement kinetic measurement, vibration measurement and monitoring, ultraprecise equipment and the system integration, scientific research and experiment.Laser vibration measurer based on laser interferance method can be divided into homodyne and the big class of heterodyne two according to principle, and the two has significant difference on operation principle, light channel structure and technical characterstic.The null method of measurement adopts single-frequency laser as light source, based on Michelson laser interference principle that is classical or that improve, changes direct displacement by measuring the phase place of interference fringe；And heterodyne measurement method is usually employing double-frequency laser as light source, based on Doppler effect, the indirect displacement by the movement velocity of measurement Doppler frequency difference measurement measured piece.Its signal processing of homodyne laser vibration measurer is substantially by luminous intensity measurement, system itself is straight-flow system, having that simple in construction, certainty of measurement be high, wide dynamic range, the non-linear advantages such as compensation that are prone to, shortcoming is that poor anti jamming capability, measurement result are changed by light intensity and affect greatly.Heterodyne laser vialog (often claims laser doppler vialog), and its signal processing is substantially by frequency measurement, system itself is dynamic communication system, have that capacity of resisting disturbance is strong, certainty of measurement is high, measurement result is affected the features such as little by light intensity change, and therefore heterodyne measurement method is constantly subjected to the concern of research worker and becomes the study hotspot of this area.
Difference interference measuring requires to interfere vialog two to form certain frequency difference between arm.Produce the method for frequency difference mainly by Zeemen effect and acousto-optic modulation.Zeemen effect is affected by frequency difference latch-up phenomenon, and the double frequency frequency difference of generation is typically small, and usual maximum frequency difference is less than 4MHz.The frequency difference that acousto-optic modulation method obtains is generally relatively big, and frequency difference reaches more than 20MHz, and frequency stability is very good, it is possible to meet the demand of high speed, high-acruracy survey.
The existing heterodyne laser vialog (1.MartinB producing frequency difference based on acousto-optic modulation, et.al. " High-precisionlaservibrometersbasedondigitalDoppler-sign alprocessing ", ProceedingsofSPIE, Vol.4827:50-61,2002；2.StefanFranz, et.al. " Heterodyneinterferometerhavinganopticalmodulator " .USPatent:US7688451B2；) it is based on Mach-Zehnder interferometer, adopt frequency stabilized carbon dioxide laser as light source, form two by polarization spectroscope PBS light splitting and interfere arm, as measuring arm and reference arm, interfering at least one adopts acousto-optic modulator to realize frequency displacement on arm, so that two are interfered and form frequency difference between arm；Plane mirror, polarization spectroscope PBS and non-polarization Beamsplitter NBS is adopted to carry out light beam closing light again.The frequency difference of the double-frequency laser that monophone optical frequency shift technical scheme produces is big, system hardware rate request is high, for solving this problem, dual-acousto-optic modulation technique scheme can be adopted to produce the light beam that two-way frequency difference is relatively small, respectively as reference light and measurement light, although dual-acousto-optic modulation scheme can reduce frequency difference, but adds optical system complexity.To sum up, the shortcoming that prior art exists is: 1) prior art is all based on Mach-Zehnder interferometer, interfere arm and measurement arm entirety rectangular, by the polarization spectroscope apex light splitting at rectangle, again through extra polarization spectroscope PBS, non-polarization Beamsplitter NBS and reflecting mirror at the diagonal angle place of optical splitting point conjunction light, there is multiple polarization spectroscope PBS in this technical scheme, there is polarisation leakage phenomenon, causes that light path nonlinearity erron is notable；2) operation principle according to acousto-optic modulator, only can there is frequency displacement in first-order diffraction light, but there is certain angle with incident beam, so that light path is closed light difficulty, reference light and measurement light and is difficult to interfere.
Due to factors such as acousto-optic modulator first-order diffraction light and incident illumination are not parallel and optical element is undesirable, especially the polarisation leakage of polarization spectroscope PBS, cause that existing heterodyne laser vialog technical scheme adjusts difficulty, and by light channel structure, principle and the undesirable restriction of optics self character, there is the nonlinearity erron being difficult to overcome, it is difficult to meet sub-nanometer of even micromicron class precision vibration measurement demand.Therefore, how by light channel structure and the innovation in principle, it is provided that the heterodyne laser vibration measuring technical scheme that a kind of light path adjustment is simple or nonlinearity erron is less, meaning is very great.
Summary of the invention
It is an object of the invention to the light path that once moral heterodyne laser vibration measuring technical scheme existed on light channel structure and principle for existing Mach and adjust difficulty, the problems such as nonlinearity erron, a kind of anti-polarization aliasing Michelson heterodyne laser vialog based on dual-acousto-optic modulation and depolarization light splitting is provided, innovation by light channel structure Yu principle, based on Michelson's interferometer, adopt less optical element to realize heterodyne laser interference to measure, adjust simple and convenient, can effectively solve light path in prior art exist polarization leakage with polarization aliasing notable, the problem that light path adjusts difficulty.
The technical solution of the present invention is:
A kind of anti-polarization aliasing Michelson heterodyne laser vialog based on dual-acousto-optic modulation and depolarization light splitting, by laser instrument, non-polarization Beamsplitter, first sound-optic modulator, the first light beam turn back element, measure prism of corner cube, second sound-optic modulator, the second light beam turn back element, reference angle cone prism, high-speed photodetector form, it is characterized in that: described laser instrument sends line polarized light, light splitting is carried out through non-polarization Beamsplitter, reflection light forms the first light beam as measuring light, and transmission light forms the second light beam as reference light；First light beam produces the first diffracted beam through first sound-optic modulator, first diffracted beam is turned back after element adjustment through the first light beam, direction of beam propagation is parallel to the first light beam, after measuring prism of corner cube reflection, forms the 3rd light beam then through non-polarization Beamsplitter transmission；Second light beam produces the second diffracted beam through second sound-optic modulator, second diffracted beam is turned back after element adjustment through the second light beam, direction of beam propagation is parallel to the second light beam, after reference angle cone prism reflects, reflects to form the 4th light beam then through non-polarization Beamsplitter；3rd light beam, the 4th beam path overlap and polarization direction is identical；3rd light beam, the 4th light beam interfere, and are received by high-speed photodetector.
Described first and second light beam element of turning back is plane mirror or wedge.
The first-order diffraction light of described first and second acousto-optic modulator is orthogonal with incident light polarization.
Described laser instrument is frequency stabilized carbon dioxide laser.
The technological innovation of the present invention and the good result of generation are in that:
(1) present invention proposes a kind of Michelson heterodyne laser vibration measuring technical scheme based on acousto-optic modulation.This technical scheme is based on Michelson's interferometer, and light path is simple, and components and parts are less, decreases the link that nonlinearity erron produces；Utilize the characteristic of acousto-optic modulator first-order diffraction light generation frequency displacement, make two to interfere and between arm, form frequency difference；Adopt prism of corner cube as measuring mirror and reference mirror, make the return light of interference arm be positioned at above acousto-optic modulator, only through an acousto-optic modulator, it is achieved thereby that heterodyne laser interference is measured.By above-mentioned technological innovation, efficiently solve prior art path optics element more, the problem that nonlinearity erron source is more.
(2) present invention only need to adjust and interfere the light beam on arm to be turned back element, the direction of propagation making first-order diffraction light beam is parallel with incident beam or zero order beam, reference light and measurement light can being made to interfere by the position of adjustment measurement prism of corner cube and reference angle cone prism, light path adjusts very convenient.Solve the problem that prior art light path adjusts inconvenience.
(3) present invention adopts depolarization Amici prism NBS equal proportion light splitting, dichroism is unrelated with the polarization state of incident illumination, therefore principle, suppress polarisation leakage and aliasing, the present invention efficiently solves serious polarisation leakage and polarization aliasing, the significant problem of measurement result nonlinearity erron that prior art exists.
Accompanying drawing explanation
Fig. 1 is the present invention anti-polarization aliasing Michelson heterodyne laser vialog three-dimensional views based on dual-acousto-optic modulation and depolarization light splitting；
Fig. 2 is the present invention light path principle diagram based on dual-acousto-optic modulation and the anti-polarization aliasing Michelson heterodyne laser vialog of depolarization light splitting；
Fig. 3 is the present invention three-dimensional views based on dual-acousto-optic modulation and anti-polarization aliasing Michelson heterodyne laser another embodiment of vialog of depolarization light splitting；
Fig. 4 is the present invention light path principle diagram based on dual-acousto-optic modulation and anti-polarization aliasing Michelson heterodyne laser another embodiment of vialog of depolarization light splitting；
Fig. 5 is the acousto-optic modulator operation principle of the present invention；
Fig. 6 is the principles of signal processing figure of the present invention；
In figure, 1 laser instrument, 2 non-polarization Beamsplitters, 3 first sound-optic modulators, 4 measure prism of corner cubes, 5 second sound-optic modulators, 6 second light beams turn back element, 7 reference angle cone prisms, 8 high-speed photodetectors, 9 first light beams, 10 second light beams, 11 second diffracted beams, 12 the 3rd light beams, 13 the 4th light beams, 14 first light beams are turned back element, 15 first diffracted beams.
Detailed description of the invention
Below in conjunction with accompanying drawing, the specific embodiment of the present invention is described in detail, and provides embodiment.
A kind of anti-polarization aliasing Michelson heterodyne laser vialog based on dual-acousto-optic modulation and depolarization light splitting, by laser instrument 1, non-polarization Beamsplitter 2, first sound-optic modulator the 3, first light beam turn back element 14, measure prism of corner cube 4, second sound-optic modulator the 5, second light beam turns back element 6, reference angle cone prism 7, high-speed photodetector 8 form, it is characterized in that: described laser instrument 1 sends line polarized light, light splitting is carried out through non-polarization Beamsplitter 2, reflection light forms the first light beam 9 as measuring light, and transmission light forms the second light beam 10 as reference light；First light beam 9 produces the first diffracted beam 15 through first sound-optic modulator 3, first diffracted beam 15 is turned back after element 14 adjustment through the first light beam, direction of beam propagation is parallel to the first light beam 9, after measuring prism of corner cube 4 reflection, forms the 3rd light beam 12 then through non-polarization Beamsplitter 2 transmission；Second light beam 10 produces the second diffracted beam 11 through second sound-optic modulator 5, second diffracted beam 11 is turned back after element 6 adjustment through the second light beam, direction of beam propagation is parallel to the second light beam 10, after reference angle cone prism 7 reflects, reflects to form the 4th light beam 13 then through non-polarization Beamsplitter 2；3rd light beam the 12, the 4th light beam 13 light path overlaps and polarization direction is identical；3rd light beam the 12, the 4th light beam 13 interferes, and is received by high-speed photodetector 8.
Described first and second light beam turns back element 14,6 for plane mirror or wedge.
The first-order diffraction light of described first and second acousto-optic modulator 3,5 is orthogonal with incident light polarization.
Described laser instrument 1 is frequency stabilized carbon dioxide laser.
Give as one embodiment of the present of invention in conjunction with Fig. 1 and Fig. 2.In the present embodiment, first and second light beam turns back element 14,6 for plane mirror.Laser instrument 1 adopts the He-Ne laser instrument through frequency stabilization, and wavelength is 632.8nm, noise < 0.05%rms, and output is 1mW, and polarization turns to 1000:1, and frequency is ω0, in space coordinates xyz, laser instrument 1 sends line polarized light, and polarization direction is x-axis, is P light.Through non-polarization Beamsplitter 2 equal proportion light splitting, the reflection light of P component forms the transmission light as the first light beam 9, the P component measuring light and forms the second light beam 10 as reference light.Measuring on arm, the first light beam 9 of P component is through first sound-optic modulator 3, and the driving frequency of first sound-optic modulator 3 is ωc1, the first diffracted beam 15 of outgoing is S light, and frequency is ω0+ωc1, the direction of propagation and incident illumination have certain angle.First diffracted beam 15 is after plane mirror adjusts, and the direction of propagation is parallel with the first light beam 9, reflects through measuring prism of corner cube 4, and the return light measuring arm is positioned at above first sound-optic modulator 3, forms the 3rd light beam 12 then through non-polarization Beamsplitter 2 transmission.The athletic meeting measuring prism of corner cube 4 produces Doppler frequency shift ± ωd, the return light frequency therefore measuring arm is ω0+ωc1±ωd.On reference arm, the second light beam 10 of P component is through second sound-optic modulator 5, and the driving frequency of second sound-optic modulator 5 is ωc2, the second diffracted beam 11 of outgoing is S light, and frequency is ω0+ωc2, the direction of propagation and incident illumination have certain angle.Second diffracted beam 11 is after plane mirror adjusts, and the direction of propagation is parallel with the second light beam 10, reflects through reference angle cone prism 7, and the return light of reference arm is positioned at above second sound-optic modulator 5, reflects to form the 4th light beam 13 then through non-polarization Beamsplitter 2.Measure light the 3rd light beam 12, reference light the 4th light beam 13 overlaps, polarization direction is identical, interferes, and frequency is Δ ωc±ωdInterference signal received by high-speed photodetector 8, wherein Δ ωcThe driving frequency being two acousto-optic modulators is poor, i.e. Δ ωc=ωc1-ωc2.In the present embodiment, high-speed photodetector 8 is the photodetector of SiPIN type, and photosensitive area diameter is 0.8mm, bandwidth 200MHz.
Fig. 3 and Fig. 4 provides an alternative embodiment of the invention.In the present embodiment, first and second light beam turns back element 14,6 for being wedge, according to law of refraction principle, changes direction of beam propagation.
Fig. 5 is the acousto-optic modulator operation principle diagram of the present invention.In the present embodiment, for second sound-optic modulator 5, the acousto-optic crsytal of acousto-optic modulator is bragg cell, inherent character due to Prague acoustooptic diffraction, hyperacoustic frequency can not be too little, is typically no less than 20MHz, then the double-frequency laser frequency difference being obtained in that equals to or more than 20MHz.When incident illumination oblique incidence to acousto-optic modulator, emergent light only has diffraction zero-level light and one-level light, and the frequency of diffraction zero-level light is identical with incident illumination with direction, diffraction one-level light generation frequency displacement, and the direction of propagation and zero order light or incident illumination have a deflection angle.Diffraction zero-level polarization state is consistent with incident illumination, and one-level light is orthogonal with incident light polarization.
Fig. 6 is the principles of signal processing diagram of the present invention.The reference signal cos ω of first sound-optic modulator 3c1The reference signal cos ω of t and second sound-optic modulator 5c2T is multiplied, and obtains the reference signal cos Δ ω of lower frequency after low-pass filteredcT；Measurement signal cos (the Δ ω that high-speed photodetector 8 receivesc±ωd) t respectively with the reference signal cos Δ ω of lower frequencycThe sin Δ ω of t and its phase shift 90 °cT is multiplied, and after low-pass filtered, A/D changes respectively, obtains orthogonal signalling, then obtains the phase place of moving object through arctangent computation
Claims (4)
1. the anti-polarization aliasing Michelson heterodyne laser vialog based on dual-acousto-optic modulation and depolarization light splitting, by laser instrument (1), non-polarization Beamsplitter (2), first sound-optic modulator (3), first light beam is turned back element (14), measure prism of corner cube (4), second sound-optic modulator (5), second light beam is turned back element (6), reference angle cone prism (7), high-speed photodetector (8) forms, it is characterized in that: described laser instrument (1) sends line polarized light, light splitting is carried out through non-polarization Beamsplitter (2), reflection light forms the first light beam (9) as measuring light, transmission light forms the second light beam (10) as reference light；First light beam (9) produces the first diffracted beam (15) through first sound-optic modulator (3), first diffracted beam (15) is turned back after element (14) adjustment through the first light beam, direction of beam propagation is parallel to the first light beam (9), after measuring prism of corner cube (4) reflection, form the 3rd light beam (12) then through non-polarization Beamsplitter (2) transmission；Second light beam (10) produces the second diffracted beam (11) through second sound-optic modulator (5), second diffracted beam (11) is turned back after element (6) adjustment through the second light beam, direction of beam propagation is parallel to the second light beam (10), after reference angle cone prism (7) reflects, reflect to form the 4th light beam (13) then through non-polarization Beamsplitter (2)；3rd light beam (12), the 4th light beam (13) light path overlap and polarization direction is identical；3rd light beam (12), the 4th light beam (13) interfere, and are received by high-speed photodetector (8).
2. according to claim 1 based on dual-acousto-optic modulation and the anti-polarization aliasing Michelson heterodyne laser vialog of depolarization light splitting, it is characterised in that: described first and second light beam element (14,6) of turning back is plane mirror or wedge.
3. the anti-polarization aliasing Michelson heterodyne laser vialog based on dual-acousto-optic modulation and depolarization light splitting according to claim 1, it is characterised in that: the first-order diffraction light of described first and second acousto-optic modulator (3,5) is orthogonal with incident light polarization.
4. the anti-polarization aliasing Michelson heterodyne laser vialog based on dual-acousto-optic modulation and depolarization light splitting according to claim 1, it is characterised in that: described laser instrument (1) is frequency stabilized carbon dioxide laser.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510338682.1A CN104990619B (en) | 2015-06-12 | 2015-06-12 | Michelson heterodyne laser vialog based on dual-acousto-optic modulation and depolarization light splitting |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510338682.1A CN104990619B (en) | 2015-06-12 | 2015-06-12 | Michelson heterodyne laser vialog based on dual-acousto-optic modulation and depolarization light splitting |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN104990619A CN104990619A (en) | 2015-10-21 |
| CN104990619B true CN104990619B (en) | 2016-06-29 |
Family
ID=54302461
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510338682.1A Active CN104990619B (en) | 2015-06-12 | 2015-06-12 | Michelson heterodyne laser vialog based on dual-acousto-optic modulation and depolarization light splitting |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN104990619B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106338334B (en) * | 2016-09-26 | 2019-01-15 | 中北大学 | A kind of dual-acousto-optic phase modulation conjugation heterodyne detection device |
| CN109581831B (en) * | 2017-09-29 | 2020-06-16 | 上海微电子装备（集团）股份有限公司 | Optical signal processing device and method |
| CN110849593B (en) * | 2019-11-22 | 2021-06-01 | 中国科学院长春光学精密机械与物理研究所 | Measuring equipment for measuring wave aberration of optical system based on heterodyne interference of acousto-optic modulator |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2582807A1 (en) * | 1985-05-30 | 1986-12-05 | France Etat Armement | Compact heterodyne interferometric device using polarised light |
| JPH07280658A (en) * | 1994-04-11 | 1995-10-27 | Noboru Nakatani | Cross beam type orthogonal two frequency light source for heterodyne interferometer |
| CN102853770A (en) * | 2012-09-19 | 2013-01-02 | 哈尔滨工业大学 | Method and device for measuring novel laser heterodyne interference based on small frequency difference and beam splitting |
| CN202853565U (en) * | 2012-06-29 | 2013-04-03 | 上海理工大学 | Acousto-optic heterodyne ineterferometer light path device |
| CN203102703U (en) * | 2013-01-29 | 2013-07-31 | 苏州舜新仪器有限公司 | Novel laser heterodyne interference experimental instrument |
| CN104296678A (en) * | 2014-09-29 | 2015-01-21 | 中国科学院光电研究院 | Heterodyne interferometer based on phase shift of low-frequency-difference acousto-optic frequency shifter |
| CN104316158A (en) * | 2014-10-21 | 2015-01-28 | 四川大学 | Heterodyne interferometer vibration measurer based on laser doppler effect |
-
2015
- 2015-06-12 CN CN201510338682.1A patent/CN104990619B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2582807A1 (en) * | 1985-05-30 | 1986-12-05 | France Etat Armement | Compact heterodyne interferometric device using polarised light |
| JPH07280658A (en) * | 1994-04-11 | 1995-10-27 | Noboru Nakatani | Cross beam type orthogonal two frequency light source for heterodyne interferometer |
| CN202853565U (en) * | 2012-06-29 | 2013-04-03 | 上海理工大学 | Acousto-optic heterodyne ineterferometer light path device |
| CN102853770A (en) * | 2012-09-19 | 2013-01-02 | 哈尔滨工业大学 | Method and device for measuring novel laser heterodyne interference based on small frequency difference and beam splitting |
| CN203102703U (en) * | 2013-01-29 | 2013-07-31 | 苏州舜新仪器有限公司 | Novel laser heterodyne interference experimental instrument |
| CN104296678A (en) * | 2014-09-29 | 2015-01-21 | 中国科学院光电研究院 | Heterodyne interferometer based on phase shift of low-frequency-difference acousto-optic frequency shifter |
| CN104316158A (en) * | 2014-10-21 | 2015-01-28 | 四川大学 | Heterodyne interferometer vibration measurer based on laser doppler effect |
Also Published As
| Publication number | Publication date |
|---|---|
| CN104990619A (en) | 2015-10-21 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104897270B (en) | Michelson heterodyne laser vialog based on monophone light modulation and polarization spectro | |
| CN108692663B (en) | Phase modulation type orthogonal polarization laser feedback grating interferometer and measuring method thereof | |
| CN104880244B (en) | The Michelson heterodyne laser vialog being divided based on monophone light modulation and depolarization | |
| CN104897271B (en) | Single channel linear polarization is interfered and single Wo Lasite prismatic decomposition formula homodyne laser vibration measurer | |
| CN104913838B (en) | Single channel circular polarization is interfered and single Wo Lasite prismatic decomposition formula homodyne laser vibration measurer | |
| CN104931125B (en) | Two-way linear polarization is interfered and single Wo Lasite prismatic decomposition formula homodyne laser vibration measurer | |
| US4688940A (en) | Heterodyne interferometer system | |
| CN104931124B (en) | Based on dual-acousto-optic modulation and the Michelson heterodyne laser vialog of polarization spectro | |
| CN104897047A (en) | Quadrature error-free double-path polarization interference and double-Wollaston prism light-splitting type homodyne laser vibration meter | |
| CN108645343B (en) | A kind of laser heterodyne interference measuring device and method based on prism of corner cube reflection | |
| CN101413783A (en) | Double-frequency laser interferometry apparatus | |
| CN107192336A (en) | Displacement measurement system and method during dual wavelength superhet interference large-range high-precision real | |
| WO2020007218A1 (en) | Two-degree-of-freedom heterodyne grating interferometry measurement system | |
| CN104897273A (en) | Quadrature error-free single-path circular polarization interference and double-Wollaston prism light-splitting type homodyne laser vibration meter | |
| CN102853769B (en) | High-speed and high-resolution laser heterodyne interferometry method and high-speed and high-resolution laser heterodyne interferometry device | |
| CN104990619B (en) | Michelson heterodyne laser vialog based on dual-acousto-optic modulation and depolarization light splitting | |
| CN103245285A (en) | Reflective point-diffraction carrier synchronization phase-shifting interference detection device and detection method | |
| CN102865820B (en) | Light path compensation based laser heterodyne interference measurement method and light path compensation based laser heterodyne interference measurement device | |
| CN104897048A (en) | Quadrature error-free single-path polarization interference and double-Wollaston prism light-splitting type homodyne laser vibration meter | |
| CN103743336A (en) | Method and device of heterodyne interferometry of incident light and laser at opposite angles based on rectangular prism | |
| CN207019624U (en) | A kind of dual wavelength superhet interferes real-time displacement measuring system | |
| CN202547607U (en) | Common-path optical coherence tomography (OCT) interval measuring system with extra-large range | |
| CN112433221A (en) | Absolute distance measuring device based on polarization modulation | |
| CN106643478A (en) | Displacement measurement optical system | |
| CN103322912A (en) | Reflection type point diffraction off-axis simultaneous phase shifting interference detection device and method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |