CN108692663A - Phase modulation-type cross-polarization Laser feedback grating interferometer and its measurement method - Google Patents
Phase modulation-type cross-polarization Laser feedback grating interferometer and its measurement method Download PDFInfo
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- 238000005388 cross polarization Methods 0.000 title claims abstract description 33
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- 238000006073 displacement reaction Methods 0.000 claims abstract description 30
- 238000012545 processing Methods 0.000 claims abstract description 13
- 230000003287 optical effect Effects 0.000 claims abstract description 9
- 230000010287 polarization Effects 0.000 claims abstract description 8
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- 229910021532 Calcite Inorganic materials 0.000 claims description 2
- 239000005352 borofloat Substances 0.000 claims description 2
- 238000006243 chemical reaction Methods 0.000 claims description 2
- 239000011521 glass Substances 0.000 claims description 2
- 239000000758 substrate Substances 0.000 claims description 2
- LSGOVYNHVSXFFJ-UHFFFAOYSA-N vanadate(3-) Chemical compound [O-][V]([O-])([O-])=O LSGOVYNHVSXFFJ-UHFFFAOYSA-N 0.000 claims description 2
- 229910052727 yttrium Inorganic materials 0.000 claims description 2
- VWQVUPCCIRVNHF-UHFFFAOYSA-N yttrium atom Chemical compound [Y] VWQVUPCCIRVNHF-UHFFFAOYSA-N 0.000 claims description 2
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- 238000005259 measurement Methods 0.000 abstract description 18
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- 235000019687 Lamb Nutrition 0.000 abstract description 2
- 238000005317 semiclassical theory Methods 0.000 abstract description 2
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- 238000004556 laser interferometry Methods 0.000 description 1
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
- G01B11/02—Measuring arrangements characterised by the use of optical techniques for measuring length, width or thickness
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B9/00—Measuring instruments characterised by the use of optical techniques
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Abstract
The present invention relates to a kind of phase modulation-type cross-polarization Laser feedback grating interferometer and its measurement method for two-dimensional measurement, measuring principle is based on optical grating diffraction, optical Doppler effect, Lamb semiclassical theories and time domain orthogonal demodulation principle.Crossed polarized light vertical incidence to the polarization splitting prism of birefringence double-frequency He-Ne laser output is divided into the linearly polarized light in two beam different polarization directions, this two beams polarised light is respectively respectively by speculum on ± 1 grade of Littrow incident angles to reflective diffraction gratings after two different electrooptic modulators.Along respective incident light return laser light intracavitary and intracavitary light self-mixed interference occurs for diffraction light respectively.Only retain single-mode optics after laser after polarizing film to output light, and received by photodetector, photodetector output signal exports to data processing module and carries out data processing, obtains the two-dimension displacement of object to be measured.The present invention has many advantages, such as simple in structure, and measurement range is big, Measurement Resolution is high.
Description
Technical field
The invention belongs to accurate displacement field of measuring technique, more particularly to a kind of phase modulation-type for two-dimensional measurement
Cross-polarization Laser feedback grating interferometer and its measurement method.
Background technology
Nano measurement is the key technology of advanced manufacturing industry development, and the guide in entire nanosecond science and technology field and basis.
With the development of Ultra-precision Turning and superfine processing technology, the demand to real-time high-precision two-dimensional positioning system increases rapidly.
Laser interferometer and grating interferometer are non-contact due to having many advantages, such as, high-resolution and wide range of dynamic measurement and used extensively
In high precision position shift measurement.In general, laser interferometry is used for measuring surface outer displacement, and grating interference measures and is then used to measure
In-plane displacement.
It can realize at present in the solution of two-dimensional measurement mainly by using two groups of interferometers, using two-dimensional grating
The speculum of interferometer is replaced to realize with light splitting technology or with reflecting grating.The use of two groups of interferometers is most straightforward approach,
But cannot its simultaneity be unable to get guarantee.Grating interferometer based on two-dimensional diffraction gratings high-precision two-dimensional positioning side at the same time
Face shows good performance, but the system is that grating is arranged in reflecting surface, utilizes the two dimension in two-dimensional grating realization face
The measurement of displacement, and the cost of manufacture of two-dimensional grating is sufficiently expensive.In some specific application scenes, such as based on the close of probe
Microscope and optical imagery, a kind of quasi- confocal optical path heterodyne grating interferometer can also realize measurement high-precision two-dimensional face in.
In recent years, the interferometer for the heterodyne grating for replacing speculum with reflecting grating has obtained many concerns, it is by a reference grating
Grating composition is measured with one, displacement that can simultaneously in measuring surface outside knead dough.Later, in the face much based on this method and
Face outer displacement measuring system is developed.But this kind of system generally faces two problems:When target is in plane outside direction
When mobile a distance, the light path of these systems will also change, and lead to occur deviation between detection light and photoelectric detector.Cause
This, the measurement of plane outer displacement is commonly used in giving in-plane displacement measurement redeeming;And these light path systems are often very
It is complicated, it is difficult to adjust.
Invention content
The technical problem to be solved by the present invention is to:
In order to make two-dimensional micro-displacement measuring device that there is wide range, high-resolution and be measured suitable for industry spot, this hair
It is bright to propose a kind of phase modulation-type cross-polarization Laser feedback grating interferometer and its measurement method.
The present invention uses following technical scheme to solve above-mentioned technical problem:
It is proposed a kind of phase modulation-type cross-polarization Laser feedback grating interferometer, it includes:Birefringence double-frequency He-Ne swashs
Light device 1, Wollaston prism 2, the first electrooptic modulator 3, the second electrooptic modulator 4, electrooptic modulator driver 5, first are flat
Face speculum 6, second plane mirror 7, reflective diffraction gratings 8, polarizing film 9, photodetector 10 and signal processing module
A。
The birefringence double-frequency He-Ne laser 1 sends out cross-polarization laser, is divided into partially through the Wollaston prism 2
Shake two different beam laser of direction, and horizontal polarization light therein is through first electrooptic modulator 3, by first speculum 6
With on+1 grade of Littrow incident angles to the reflecting grating 8, orthogonal polarized light is through second electrooptic modulator 4, by institute
The second speculum 7 is stated on -1 grade of Littrow incident angles to the reflecting grating 8;The output of electrooptic modulator driver 5 two
The voltage signal of kind of different frequency respectively drives two electrooptic modulators 3, and 4, and both voltage signals are corresponding with reference to believing
Number output is to signal processing module A;The diffraction light that laser light incident is generated to the reflecting grating 8 is described sharp along incident path return
With intracavitary light laser feedback interference occurs for light device 1;The polarizing film 9 is placed in after the He-Ne laser 1 on output light path,
The photodetector 10 is placed in 9 rear of polarizing film, the output of photodetector 10 to signal processing module A;
The signal processing module A includes:Operational amplifier 11, the first bandpass filter 12, the second bandpass filter 13,
Third bandpass filter 14, the 4th bandpass filter 15, data collecting card 16 and computer 17;Detectable signal is input to the fortune
Amplifier 11 is calculated, the operational amplifier 11 exports amplified signal into the first to fourth bandpass filter 12-15, and four
A filtering signal is exported simultaneously to the data collecting card 16, and the data collecting card 16 inputs the meter after carrying out analog-to-digital conversion
Calculation machine 17 obtains waiting for displacement after being handled by the computer 17.
Foregoing phase modulation-type cross-polarization Laser feedback grating interferometer, further, the birefringence is double
Frequency He-Ne laser 1 exports double-bus network cross-polarization laser, and there are mode competitions between two patterns.
Foregoing phase modulation-type cross-polarization Laser feedback grating interferometer, further, the Wollaston
Prism 2 uses α-BBO, calcite or Yttrium Orthovanadate for substrate, and the angle of departure of outgoing beam is between 17 °~23 °.
Foregoing phase modulation-type cross-polarization Laser feedback grating interferometer, further, the Electro-optical Modulation
3,4 major axes orientation of device with by laser polarization direction it is consistent;The electrooptic modulator be used for by laser carry out pure phase
Position modulation.
Foregoing phase modulation-type cross-polarization Laser feedback grating interferometer, further, the Electro-optical Modulation
Device 3,4 be used for by laser carry out sinusoidal phase modulation, modulation amplitude is pi/2, modulation initial phase be 0;Described first
The ratio between electrooptic modulator 3 and the modulating frequency of second electrooptic modulator 4 are 3:7.
Foregoing phase modulation-type cross-polarization Laser feedback grating interferometer, further, the Electro-optical Modulation
Device 3,4 uses waveguide shape electro-optic crystal.
Foregoing phase modulation-type cross-polarization Laser feedback grating interferometer, it is further, described reflective to spread out
It is the holographic grating that Borofloat glass makes to penetrate grating 8.
Foregoing phase modulation-type cross-polarization Laser feedback grating interferometer, further, the polarizing film 9
Polarization direction is adjusted to only the o light of birefringence double-frequency He-Ne laser or e light to be allowed to pass through.
Foregoing phase modulation-type cross-polarization Laser feedback grating interferometer, further, first band logical
The centre frequency of filter 12 is equal to the modulating frequency of first electrooptic modulator, the center of second bandpass filter 13
Frequency is equal to two times of the modulating frequency of first electrooptic modulator, and the centre frequency of the third bandpass filter 14 is equal to
The centre frequency of the modulating frequency of second electrooptic modulator, the 4th bandpass filter 15 is equal to the second electric light tune
Two times of the modulating frequency of device processed;The bandwidth of the first to fourth bandpass filter 12-15 is identical and nonoverlapping in passband
Under the premise of reach maximum.
The present invention also proposes a kind of measurement based on phase modulation-type cross-polarization Laser feedback grating interferometer above-mentioned
Method, wherein phase demodulating uses time domain orthogonal demodulation techniques, and specific steps include:
(1) filtering signal of the first to fourth bandpass filter 12-15 outputs is handled with real-time normalization algorithm;
(2) to treated, filtering signal removes respective carrier wave respectively, obtain two groups of phases to be measured sinusoidal component and
Cosine component;
(3) two groups of phases to be measured are demodulated;
(4) according to the linear relationship between two groups of phases to be measured and 8 two-dimension displacement of the reflecting grating, target is measured in real time
Displacement.
The present invention has the following technical effects using above technical scheme is compared with the prior art:
1) present invention uses Laser feedback grating interference principle, does not need the auxiliary such as the reference grating of traditional raster interferometer
Element, the two-beam of cross-polarization feed back to laser simultaneously and interfere, and a photodetector is only needed to signal detection
It can be realized, enormously simplify the structure of light path system, optical path adjusting is convenient.
2) relative to the existing grating interference technology measured for realizing two-dimension displacement, the present invention utilizes Littrow structure
Advantage, in grating generating surface outer displacement, light channel structure will not change correspondingly, and realize the measurement of great-scale displacement outside face, subtract
Lack number of devices, reduce system complexity.
3) present invention is proposed carries out phase-only modulation using electrooptic modulator to diffraction light, and modulation accuracy is high, modulates band
Wide, phase demodulating is realized by time domain orthogonal demodulation techniques, and demodulation method algorithm is simple, insensitive to sampling error, Ke Yi great
Amplitude improves the Measurement Resolution of displacement measuring device.
4) present invention forms new wide range, high-resolution, the two-dimensional micro-displacement measurement measured suitable for industry spot
Device, to further pushing the development of advanced manufacturing technology to have important practical significance.
Description of the drawings
Fig. 1 is the structural schematic diagram of the present invention.
Fig. 2 is the time domain orthogonal demodulation principle figure of the present invention.
Specific implementation mode
Technical scheme of the present invention is described in further detail below in conjunction with the accompanying drawings:
Those skilled in the art of the present technique are it is understood that unless otherwise defined, all terms used herein (including skill
Art term and scientific terminology) there is meaning identical with the general understanding of the those of ordinary skill in fields of the present invention.Also
It should be understood that those terms such as defined in the general dictionary should be understood that with in the context of the prior art
The consistent meaning of meaning, and unless defined as here, will not be explained with the meaning of idealization or too formal.
Laser feedback interference technology is a kind of novel interference measurement technology with very high application value of rising in recent years,
After laser output light is reflected or scattered by external object, part light will mutually mix in return laser light device resonant cavity with intracavity beam
The variation of the output intensity of laser is closed and caused, realizes the accurate measurement of the physical quantitys such as speed, displacement, vibration and distance.By
In the intrinsic simple and compact for structure, auto-collimation of system and rough interface scattering surface remarkable advantage is may operate in, solves tradition
Interferometry technological system is complicated, is sensitive to the problems such as collimation, can replace traditional laser interferometer in many occasions.
It is illustrated with reference to Fig. 1 phase modulation-type cross-polarization Laser feedback grating interferometer operation principle of the present invention.Such as Fig. 1,
The crossed polarized light vertical incidence that birefringence double-frequency He-Ne laser 1 exports to Wollaston prism 2 and is broken down into o light and e
Light.First electrooptic modulator 3 is placed in o light light paths, and phase-only modulation, modulation function M are carried out to o lightoFor:
Mo=(pi/2) sin (2 π fomt) (1)
Wherein fomFor the modulating frequency of the first electro-optic crystal 3;Second electrooptic modulator 4 is placed in e light light paths, to e light into
Row phase-only modulation, modulation function MeFor:
Me=(pi/2) sin (2 π femt) (2)
Wherein femFor the modulating frequency of the second electro-optic crystal 4.In order to accurately reflect the movement shape of reflective diffraction gratings
State, modulating frequency fomAnd femIt need to be much larger than the rate that reflective diffraction gratings generate displacement, specifically need to meet:
fom/ 3=fem/7>>vxm/d+vzm(2/λcosθ-tanθ/d) (3)
V in formulaxmFor the maximum movement speed in the reflective diffraction gratings (8) direction in face, vzmIt is described reflective
Diffraction grating (8) is in the maximum movement speed of face outside direction, and d is grating constant, and λ is the birefringence double-frequency He-Ne laser
(1) centre wavelength, θ are Littrow incidence angle.
The o light and e light for being decomposed out are reflected by the first speculum 6 and the second speculum 7 respectively, respectively with+1 and -1 grade
On Littrow angle θ to reflectivity diffraction grating 8.The diffraction light that Littrow structure makes returns to double along input path
It reflects 1 intracavitary of double frequency He-Ne laser and laser feedback interference occurs with intracavitary light.
When the directions x move Δ x to reflective diffraction gratings 8 along figure, o caused by the displacement by reflective diffraction gratings 8
The feedback light phase change of light is:
Wherein d is grating constant.The feedback light phase change of e light is:
When the directions z move Δ z to reflective diffraction gratings 8 along figure, o caused by the displacement by reflective diffraction gratings 8
The feedback light phase change of light and e light is:
Wherein θ is Littrow incidence angle.Since o light and e light pass through electrooptic modulator twice in exocoel respectively, by electric light
Modulator causes the feedback light phase change of o light and e light to be respectively:
The feedback light phase total variation of o light and e light is respectively:
According to Lamb semiclassical theories, the output light field E of double-longitudinal-mode lasero/eIt (t) can be with table under three rank perturbation approximations
It is shown as:
Eo=E0+(αoβe-αeθoe)/(βoβe-θoeθeo) (11)
Ee=E0+(αeβo-αoθeo)/(βoβe-θoeθeo) (12)
In formula, subscript o and e respectively represent the corresponding variable of o light and the corresponding variable of e light, and the meaning of each variable is:E0For
Initial beam intensity, αo, αeFor the linear gain coefficient of o light and e light, βo, βeFor the light intensity self-saturation constant of o light and e light, θoe, θeoFor
The mutual saturation constant of o light and e light.Wherein linear gain factor alphao, αeFor:
αo=α 'o-fo/Qo (13)
αe=α 'e-fe/Qe (14)
In formula, the meaning of each variable is:α'o, α 'eFor the small signal-wire gain of o light and e light, fo/e, fo/eFor o light and e
The laser optical frequency of light, Qo, QeFor the quality factor of o light and the resonant cavity of e light.Wherein quality factor qo, QeIt can be expressed as:
Qo=4 π L/[λ(2-R1-Ro)] (15)
Qe=4 π L/[λ(2-R1-Re)] (16)
In formula, the meaning of each variable is:L is that laser chamber is long, R1It is the reflection of the left end resonance mirror of laser 1 in Fig. 1
Rate, Ro, ReBe the right end resonance mirror of laser 1 is influenced the dynamic of the o light shown and e light by the exocoel that it is formed with reflecting grating 8
State reflectivity.Reflecting grating 8 is when xz planes are subjected to displacement, dynamic reflective rate Ro, ReIt can be expressed as:
In formula, the meaning of each variable is:R2It is the reflectivity of the right end resonance mirror of laser 1 in Fig. 1, η is reflecting grating 8
First order diffraction efficiency, lo, leIt is external cavity length.(13)-(18) formula is substituted into (11)-(12) formula, obtains laser feedback interference
Approximate solution:
In formula, A and B are the constant coefficient after abbreviation.(19) formula is unfolded, can be obtained:
J in formulan(π) indicates the n rank Bessel function values of π.The left side output light of laser 1 is after polarizing film 9, o light
It is filtered with the one of pattern of e light, photodetector 10 detects the output intensity of another pattern of laser 1 and is input to
In signal processing module A.Here for exporting o light, it is illustrated in combination with fig. 2 phase modulation-type cross-polarization Laser feedback of the present invention
The displacement measurement method of grating interferometer.Due to mode competition effect, optical power fluctuation caused by the feedback of e light can be also reflected in
In o light.Photodetector 10 is converted to the light intensity signal detected in electric signal output to operational amplifier 11, is amplified
Signal is divided into four parts while being input in four bandpass filter 12-15, wherein the centre frequency of the first bandpass filter 12
For the modulating frequency f of the first electrooptic modulator 3om, the centre frequency of the second bandpass filter 13 is 2fom, third bandpass filter
14 centre frequency is the modulating frequency f of the second electrooptic modulator 4em, the centre frequency of the 4th bandpass filter 15 is 2fem.Filter
Signal after wave is followed successively by:
S in formula1-S4The output signal of first to fourth bandpass filter 12-15 is respectively represented, they and Electro-optical Modulation are driven
The dynamic 5 two kinds of modulating frequency f generatedom, femCorresponding reference signal is input to together in data acquisition card 16, and by computer
17 processing.The reference signal of 5 output of Electro-optical Modulation driving is converted to 4 kinds of carrier waves by computer 17, respectively:C1=cos (2 π
fomT), C2=cos (4 π fomT), C3=cos (2 π femT), C4=cos (4 π femt).Filtered signal S1-S4Difference divided by carrier wave
C1-C4Afterwards by normalization, can obtain:
Then pattern displacement is led respectively
Cause the phase change of o light and e lightWithIt can be expressed as:
The phase Bao Guoyu [ calculated by arctan function;-π,π]Between, after unpacking operation, obtaining pattern displacement is:
The present invention provides a kind of phase modulation-type cross-polarization Laser feedback grating interferometer and a kind of measurement methods, use
In in real time measure target face in and face outer displacement, the structure of the interferometer is compacter with respect to traditional raster interferometer, protects simultaneously
The autocollimatic advantage of Laser feedback grating interferometer has been held, has been a kind of high-resolution measured suitable for industry spot, wide range
Two-dimensional displacement measurer, to further pushing the development of advanced manufacturing technology to have important practical significance.
The above is only some embodiments of the present invention, it is noted that for the ordinary skill people of the art
For member, various improvements and modifications may be made without departing from the principle of the present invention, these improvements and modifications are also answered
It is considered as protection scope of the present invention.
Claims (10)
1. phase modulation-type cross-polarization Laser feedback grating interferometer, which is characterized in that it includes:Birefringence double-frequency He-Ne swashs
Light device (1), Wollaston prism (2), the first electrooptic modulator (3), the second electrooptic modulator (4), electrooptic modulator driver
(5), the first plane mirror (6), second plane mirror (7), reflective diffraction gratings (8), polarizing film (9), photodetection
Device (10) and signal processing module (A);
The birefringence double-frequency He-Ne laser (1) sends out cross-polarization laser, is divided into partially through the Wollaston prism (2)
Shake two different beam laser of direction, and horizontal polarization light therein is through first electrooptic modulator (3), by first speculum
(6) with (8) on+1 grade of Littrow incident angles to the reflecting grating, orthogonal polarized light is through second electrooptic modulator
(4), by second speculum (7) with (8) on -1 grade of Littrow incident angles to the reflecting grating;Electrooptic modulator drives
The voltage signal that dynamic device (5) exports two kinds of different frequencies respectively drives two electrooptic modulators (3,4), and both voltages are believed
Number corresponding reference signal is exported to signal processing module (A);The diffraction light edge that laser light incident is generated to the reflecting grating (8)
Incident path returns to the laser (1), and laser feedback interference occurs with intracavitary light;The polarizing film (9) is placed in the He-Ne
On the backward output light path of laser (1), the photodetector (10) is placed in polarizing film (9) rear, and photodetector (10) is defeated
Go out to signal processing module (A);
The signal processing module (A) includes:Operational amplifier (11), the first bandpass filter (12), the second bandpass filter
(13), third bandpass filter (14), the 4th bandpass filter (15), data collecting card (16) and computer (17);Detection letter
Number it is input to the operational amplifier (11), the operational amplifier (11) exports amplified signal to first to fourth band
In bandpass filter (12-15), four filtering signals are exported simultaneously to the data collecting card (16), the data collecting card (16)
The computer (17) is inputted after carrying out analog-to-digital conversion, after being handled by the computer (17), obtains waiting for displacement.
2. phase modulation-type cross-polarization Laser feedback grating interferometer as described in claim 1, it is characterised in that:It is described double
It reflects double frequency He-Ne laser (1) and exports double-bus network cross-polarization laser, there are mode competitions between two patterns.
3. phase modulation-type cross-polarization Laser feedback grating interferometer as described in claim 1, it is characterised in that:It is described fertile
Lars prism (2) uses α-BBO, calcite or Yttrium Orthovanadate for substrate, and the angle of departure of outgoing beam is between 17 °~23 °.
4. phase modulation-type cross-polarization Laser feedback grating interferometer as described in claim 1, it is characterised in that:The electric light
Modulator (3,4) major axes orientation with by laser polarization direction it is consistent;The electrooptic modulator be used for by laser into
Row phase-only modulation.
5. phase modulation-type cross-polarization Laser feedback grating interferometer as described in claim 1, it is characterised in that:The electricity
Optical modulator (3,4) be used for by laser carry out sinusoidal phase modulation, modulation amplitude is pi/2, modulation initial phase be 0;
The ratio between first electrooptic modulator (3) and the modulating frequency of second electrooptic modulator (4) are 3:7.
6. phase modulation-type cross-polarization Laser feedback grating interferometer as described in claim 1, it is characterised in that:The electricity
Optical modulator (3,4) uses waveguide shape electro-optic crystal.
7. phase modulation-type cross-polarization Laser feedback grating interferometer as described in claim 1, it is characterised in that:It is described anti-
It is the holographic grating that Borofloat glass makes to penetrate formula diffraction grating (8).
8. phase modulation-type cross-polarization Laser feedback grating interferometer as described in claim 1, it is characterised in that:It is described inclined
Shake piece (9) polarization direction be adjusted to only allow birefringence double-frequency He-Ne laser o light or e light pass through.
9. phase modulation-type cross-polarization Laser feedback grating interferometer as described in claim 1, it is characterised in that:Described
The centre frequency of one bandpass filter (12) is equal to the modulating frequency of first electrooptic modulator, second bandpass filter
(13) centre frequency is equal to two times of the modulating frequency of first electrooptic modulator, the third bandpass filter (14)
Centre frequency is equal to the modulating frequency of second electrooptic modulator, and the centre frequency of the 4th bandpass filter (15) is equal to
Two times of the modulating frequency of second electrooptic modulator;The bandwidth of first to fourth bandpass filter (12-15) is identical,
And reach maximum under the premise of passband is nonoverlapping.
10. a kind of dry based on the phase modulation-type cross-polarization Laser feedback grating described in any one of claim 1~10
The measurement method of interferometer, it is characterised in that:Phase demodulating uses time domain orthogonal demodulation techniques, and specific steps include:
(1) filtering signal of first to fourth bandpass filter (12-15) output is handled with real-time normalization algorithm;
(2) to treated, filtering signal removes respective carrier wave respectively, obtains the sinusoidal component and cosine of two groups of phases to be measured
Component;
(3) two groups of phases to be measured are demodulated;
(4) according to the linear relationship between two groups of phases to be measured and the reflecting grating (8) two-dimension displacement, target position is measured in real time
It moves.
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| CN110132126A (en) * | 2019-05-21 | 2019-08-16 | 季华实验室 | Based on the displacement measuring device and method from mixing holographic interference |
| CN110261066A (en) * | 2019-03-21 | 2019-09-20 | 复旦大学 | The micro- detection light beam spotting device near field based on shear interference |
| CN110360931A (en) * | 2019-05-31 | 2019-10-22 | 中国人民解放军战略支援部队航天工程大学 | A kind of symmetrical expression compact difference interference grating displacement measuring system |
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| US11906303B2 (en) | 2019-05-24 | 2024-02-20 | Apple Inc. | Wearable skin vibration or silent gesture detector |
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| US11156456B2 (en) | 2019-05-21 | 2021-10-26 | Apple Inc. | Optical proximity sensor integrated into a camera module for an electronic device |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2732849B2 (en) * | 1987-03-24 | 1998-03-30 | ライカ・ヘールブルグ・アクチエンゲゼルシヤフト | Interferometer |
| CN103528511A (en) * | 2013-10-18 | 2014-01-22 | 南京师范大学 | Sinusoidal phase modulation type laser self-mixing interferometer and measuring method thereof |
| CN105333814A (en) * | 2015-10-16 | 2016-02-17 | 南京师范大学 | Phase modulation type laser feedback raster interferometer and measuring method thereof |
| CN106643477A (en) * | 2017-01-16 | 2017-05-10 | 南京师范大学 | Polarization multiplexing phase modulation type laser self-mixing two-dimensional interferometer and measuring method thereof |
| CN107462165A (en) * | 2017-08-23 | 2017-12-12 | 中国科学院上海光学精密机械研究所 | High optical fine dual-frequency grating interferometer based on bigrating structures |
-
2018
- 2018-04-11 CN CN201810319638.XA patent/CN108692663B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2732849B2 (en) * | 1987-03-24 | 1998-03-30 | ライカ・ヘールブルグ・アクチエンゲゼルシヤフト | Interferometer |
| CN103528511A (en) * | 2013-10-18 | 2014-01-22 | 南京师范大学 | Sinusoidal phase modulation type laser self-mixing interferometer and measuring method thereof |
| CN105333814A (en) * | 2015-10-16 | 2016-02-17 | 南京师范大学 | Phase modulation type laser feedback raster interferometer and measuring method thereof |
| CN106643477A (en) * | 2017-01-16 | 2017-05-10 | 南京师范大学 | Polarization multiplexing phase modulation type laser self-mixing two-dimensional interferometer and measuring method thereof |
| CN107462165A (en) * | 2017-08-23 | 2017-12-12 | 中国科学院上海光学精密机械研究所 | High optical fine dual-frequency grating interferometer based on bigrating structures |
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|---|---|---|---|---|
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| CN109632011B (en) * | 2019-01-23 | 2020-08-21 | 中国科学院长春光学精密机械与物理研究所 | Displacement and angle synchronous measurement system |
| CN109632011A (en) * | 2019-01-23 | 2019-04-16 | 中国科学院长春光学精密机械与物理研究所 | It is a kind of to be displaced and angle synchronized measurement system |
| CN110261066A (en) * | 2019-03-21 | 2019-09-20 | 复旦大学 | The micro- detection light beam spotting device near field based on shear interference |
| US11680788B2 (en) | 2019-04-05 | 2023-06-20 | Apple Inc. | Handling obstructions and transmission element contamination for self-mixing particulate matter sensors |
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| CN110132126A (en) * | 2019-05-21 | 2019-08-16 | 季华实验室 | Based on the displacement measuring device and method from mixing holographic interference |
| CN110132126B (en) * | 2019-05-21 | 2020-09-01 | 季华实验室 | Displacement measuring device and method based on self-mixing holographic interference |
| US11906303B2 (en) | 2019-05-24 | 2024-02-20 | Apple Inc. | Wearable skin vibration or silent gesture detector |
| CN110360931A (en) * | 2019-05-31 | 2019-10-22 | 中国人民解放军战略支援部队航天工程大学 | A kind of symmetrical expression compact difference interference grating displacement measuring system |
| CN110360931B (en) * | 2019-05-31 | 2020-11-10 | 中国人民解放军战略支援部队航天工程大学 | Symmetrical compact heterodyne interference grating displacement measurement system |
| US11692809B2 (en) | 2019-09-18 | 2023-07-04 | Apple Inc. | Self-mixing interferometry-based absolute distance measurement with distance reference |
| CN110631484A (en) * | 2019-11-04 | 2019-12-31 | 南京师范大学 | Three-dimensional displacement measurement system and method based on laser self-mixing grating interference |
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| CN114112000A (en) * | 2020-08-27 | 2022-03-01 | 精工爱普生株式会社 | Laser interferometer and method for controlling laser interferometer |
| CN114112000B (en) * | 2020-08-27 | 2024-01-16 | 精工爱普生株式会社 | Laser interferometer and control method for laser interferometer |
| US20220099431A1 (en) * | 2020-09-25 | 2022-03-31 | Apple Inc. | Self-Mixing Interferometry Device Configured for Non-Reciprocal Sensing |
| US11629948B2 (en) | 2021-02-04 | 2023-04-18 | Apple Inc. | Optical interferometry proximity sensor with optical path extender |
| CN113036599A (en) * | 2021-03-04 | 2021-06-25 | 中国科学院光电技术研究所 | Method for improving output power of Littman structure tunable external cavity semiconductor laser |
| CN115824061A (en) * | 2023-02-14 | 2023-03-21 | 中国科学院长春光学精密机械与物理研究所 | Littrow diffraction-based grating displacement measurement device and method |
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| CN117948897B (en) * | 2024-03-27 | 2024-06-04 | 中国科学院长春光学精密机械与物理研究所 | Mixed displacement measuring device |
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