CN201141770Y - Double-frequency laser interfere signal receiver with automatically adjustable high-speed gain - Google Patents
Double-frequency laser interfere signal receiver with automatically adjustable high-speed gain Download PDFInfo
- Publication number
- CN201141770Y CN201141770Y CNU2007201987514U CN200720198751U CN201141770Y CN 201141770 Y CN201141770 Y CN 201141770Y CN U2007201987514 U CNU2007201987514 U CN U2007201987514U CN 200720198751 U CN200720198751 U CN 200720198751U CN 201141770 Y CN201141770 Y CN 201141770Y
- Authority
- CN
- China
- Prior art keywords
- circuit
- signal
- connects
- output terminal
- gain automatic
- 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.)
- Expired - Lifetime
Links
Images
Landscapes
- Optical Communication System (AREA)
- Amplifiers (AREA)
Abstract
The utility model provides a high-speed gain automatic adjustable double-frequency laser interference signal receiver, which generates three gains to adjust and control signal driving analog switches, by switching on/off the analog switches are switched off and on so as to change the closed-ring gains of signal amplifying circuit, so that the amplitude of voltage signal is stabilized within +5V to +10V; weak signal inhibition control circuit is used to control the output waveform of sinusoidal-square wave conversion circuit; by adopting high-speed photoelectric diode, response frequency of interference signal can reach 1GHz; by adopting high-speed high broadband calculation amplifier, entire circuit has higher response speed and band width; the gains can adjust the amplifying circuit automatically, so as to ensure signal is not to generate distortion due to saturation during processing; weak signal inhibition circuit cuts off signal output when the strength of incident light is lower than specific amplitude, thereby avoiding generating output signal with excessive errors.
Description
Technical field
The utility model relates to a kind of double-frequency laser interference signal receiver in the high measurement speed dual frequency laser interferometer measuring system, relates to the process such as opto-electronic conversion, signal condition, waveform transformation of double-frequency laser interference signal.
Background technology
Two-frequency laser interferometer has wide-measuring range, high resolving power, high measurement accuracy and advantage such as high-speed, is that high precision advanced scanning projecting photoetching machine work stage is located indispensable survey instrument.Two-frequency laser interferometer is mainly used on the position measuring system of precision workpiece stage, particularly is used in the Precision Position Location System of the work stage of advanced scanning projecting photoetching machine.
The structure of two-frequency laser interferometer measuring system as shown in Figure 1, laser head 2 ' sends two row and has a different frequency (f
1Perpendicular to paper; f
2Be parallel to paper) linearly polarized light.Through spectroscope 3 ', light is divided into intensity 33% and 66% liang of bundle respectively.
Intensity be 33% light beam through interference mirror 4 ' with light beam according to the polarization direction with f
1, f
2Separate.If the wave equation of two-beam is:
E
1＝E
R1cos2πf
1t
E
2＝E
R2cos2πF
2t
The polarized light f that is parallel to paper
2After seeing through interference mirror 4 ', by 5 ' the reflected back interference mirror 4 ' of the measurement catoptron on the worktable, by entering receiver 1 ' after the camera lens 6 ' reception.When measuring catoptron 5 ' when mobile, produce Doppler effect, the Returning beam frequency becomes f
2± Δ f.Δ f is a Doppler shift amount.It comprises the displacement information of surveying work platform.f
1Through behind the interference mirror 4 ', final and light beam f
2± Δ f converges.The light intensity function that converges the back light beam is:
Receiver 1 ' is f with frequency
1-f
2The light signal of ± Δ f is converted to electric signal, and electric signal also comprises a DC quantity and an of ac.Behind the signal condition, remove DC quantity, it is f that of ac is converted to a class frequency
1-f
2The pulse signal of ± Δ f.
Output frequency is f from laser head
1-f
2Pulse signal, be the reference signal that subsequent conditioning circuit is handled.The test integrated circuit board adopts subtracter by to the subtracting each other of two column signals, and obtains because the change frequency Δ f that the displacement of work stage causes.The displacement L of worktable and the relation of Δ f can be expressed as:
λ is a Wavelength of Laser.
From above analysis as can be seen:, just can calculate the displacement of work stage as long as record the frequency change Δ f of pulse signal.Pulse signal is the input signal of follow-up measurement integrated circuit board, and this accurately converts the voltage pulse signal of same frequency to regard to light AC signal that needs will carry displacement information.
The principle of present commercial laser interferometer receiver as shown in Figure 2.This receiver mainly by photodetector and one-level amplifying circuit 1, manually decay that regulating circuit 2, secondary amplify 4, signal strength detection circuit 6, waveform changing circuit 7, signal drive circuit form.
Photodetector and one-level amplifying circuit 1 are voltage signal with the double-frequency laser conversion of signals and amplify, the enlargement factor of decay regulating circuit 2 control one-level amplifying circuits 1.Second amplifying circuit 4 further amplifies voltage signal.Waveform changing circuit 7 is converted to square-wave signal with sine voltage signal.The intensity of signal strength detection circuit 6 detectable voltage signals and output.Intensity detection circuit 6 gauge tap make the output high level when signal intensity is more weak, and square-wave signal is converted to differential signal through overdrive circuit 10.
Not only the light of free space may cause interference to the photodetection circuit, and circuit itself also can produce certain noise.Though these interference strengths are very weak, the test signal intensity that detector is experienced is not high yet.After amplifying, these noises can influence the precision of test.Though commercial receiver is gain that can manual adjustments first order amplifying circuit.But in the actual test process, manual adjustments is also inconvenient, even may cause the output of amplifying circuit saturated.
The utility model content
The purpose of this utility model overcomes the above problems exactly, and the receiver of designing gain automatic and adjustable is converted to the controlled differential voltage signal of amplitude with weak one, guarantees the measuring system measuring accuracy.
In order to achieve the above object, the utility model provides a kind of double-frequency laser interference signal receiver of high speed gain automatic and adjustable, comprises;
The photosignal change-over circuit; This photosignal change-over circuit comprises photodiode and the current/voltage-converted module that circuit connects;
The amplification filtering circuit, the inlet circuit of this amplification filtering circuit connects the output terminal of described photosignal conversion circuit;
Gain Automatic adjusting amplifying circuit, the inlet circuit of this Gain Automatic amplifying circuit connects the output terminal of described amplification filtering circuit;
Waveform changing circuit, the inlet circuit of this waveform changing circuit connects the output terminal of described Gain Automatic adjusting amplifying circuit;
Differential driver, the inlet circuit of this differential driver connects the output terminal of described waveform changing circuit;
Receiver described in the utility model also comprises:
Control signal generation circuit, the inlet circuit of this control signal generation circuit connects the output terminal of described amplification filtering circuit, and output terminal circuit respectively connects the input end of described Gain Automatic adjusting amplifying circuit and the input end of described waveform changing circuit;
Described gain control signal produces circuit and comprises:
The full-wave rectification amplifying circuit;
Generating circuit from reference voltage;
Gain control signal produces circuit, and the inlet circuit of this gain control signal generation circuit connects the output terminal of described full-wave rectification amplifying circuit and generating circuit from reference voltage, and circuit of output terminal connects the input end of described Gain Automatic adjusting amplifying circuit;
Weak signal suppresses circuit, and the inlet circuit of this weak signal inhibition circuit connects the output terminal of described full-wave rectification amplifying circuit and generating circuit from reference voltage, and circuit of output terminal connects the input end of described waveform changing circuit;
Principle of work of the present utility model is as follows:
Receiver detects light signal, is current signal through the photodiode converts in the photoelectric switching circuit, passes through the current/voltage-converted module then, obtains sine voltage signal;
The amplification filtering circuit carries out amplification filtering to the sine voltage signal of photoelectric switching circuit output, obtains filtered signal;
Intensity according to filtered signal, control signal generation circuit produces control signal: the full-wave rectification amplifying circuit at first carries out full-wave rectification to signal after the filtering of amplification filtering circuit output, change sinusoidal signal into d. c. voltage signal, again signal is amplified; Generating circuit from reference voltage produces reference voltage REF1, REF2, REF3 by electric resistance partial pressure; Gain control signal produces circuit reference voltage REF1, REF2, REF3 and d. c. voltage signal is carried out hysteresis relatively, when strength signal greater than a certain reference voltage, then control signal corresponding is a high level, otherwise control signal is a low level, gain control signal CON1, the CON2, the CON3 that produce control analog switch, thereby change the closed loop gain of Gain Automatic adjusting amplifying circuit; Weak signal suppresses the power of circuit according to d. c. voltage signal, the signal output of control waveform change-over circuit, if the d. c. voltage signal amplitude is too little, also be that d. c. voltage signal after the rectification is near reference voltage, it is high level that weak signal suppresses control signal, then waveform changing circuit is exported constant high level, otherwise is low level;
Adjusted sine wave gains, comparer through waveform changing circuit carries out waveform transformation, when weak signal inhibition control signal is high level, triode is opened, make the comparative voltage of the adjusted sine wave of gain reduce, because the bias voltage of the adjusted sine wave signal of gain is greater than comparative voltage, therefore the waveform changing circuit comparer is exported high level, otherwise the comparative voltage of the adjusted sine wave signal that gains equals bias voltage, thereby the waveform changing circuit comparer is converted to square-wave signal with sinusoidal signal;
Square-wave signal is converted to differential digital signal through differential driver.
The double-frequency laser interference signal receiver of a kind of high speed gain automatic and adjustable that the utility model provides, produce three gains and adjust the control signal drive analog switch, closure and unlatching by analog switch, change the closed loop gain of signal amplification circuit, make voltage signal amplitude stability+5V～+ scope of 10V in; Weak signal suppresses control circuit, the output waveform of control sine-square wave conversion circuit; Adopt high-speed photodiode, can reach 1GHz the response frequency of interference signal; Adopt the operational amplifier of high speed high bandwidth, so entire circuit have higher response speed and bandwidth; Gain Automatic adjusting amplifying circuit guarantees that signal can be because of saturated generation distortion in processing procedure; Weak signal suppresses circuit cut-off signals output when incident intensity is lower than certain amplitude, avoids occurring the excessive output signal of error.
Description of drawings
Fig. 1 is the laser interferometer fundamental diagram in the background technology;
Fig. 2 is the theory diagram of a commercialization receiver in the background technology;
Fig. 3 is a theory diagram of the present utility model;
Fig. 4 is a circuit diagram of the present utility model;
Fig. 5 is the circuit diagram of control signal generation circuit in the utility model;
Fig. 6 is the circuit diagram of generating circuit from reference voltage in the utility model;
Fig. 7 is the oscillogram of the sine voltage signal V1 of photoelectric switching circuit output;
Fig. 8 is the oscillogram of the signal V3 of amplification filtering circuit output;
Fig. 9 is the adjusted sine wave signal V4 of the gain oscillogram of Gain Automatic adjusting amplifying circuit output;
Figure 10 is receiver signal output waveform figure.
Embodiment
Followingly specify a kind of better embodiment of the present utility model according to Fig. 3～Figure 10:
As shown in Figure 3 and Figure 4, the utility model provides a kind of double-frequency laser interference signal receiver of high speed gain automatic and adjustable, comprises;
Photosignal change-over circuit 101; This photosignal change-over circuit comprises photodiode 1011 and the current/voltage-converted module 1012 that circuit connects;
Gain Automatic adjusting amplifying circuit 103, the inlet circuit of this Gain Automatic amplifying circuit 103 connects the output terminal of described amplification filtering circuit 102;
As shown in Figure 5 and Figure 6, receiver described in the utility model also comprises:
Control signal generation circuit, the inlet circuit of this control signal generation circuit connects the output terminal of described amplification filtering circuit 102, and output terminal circuit respectively connects the input end of described Gain Automatic adjusting amplifying circuit 103 and the input end of described waveform changing circuit 104;
Described control signal generation circuit comprises:
Full-wave rectification amplifying circuit 1061;
Generating circuit from reference voltage 1062;
Gain control signal produces circuit 1061, the inlet circuit of this gain control signal generation circuit 1061 connects the output terminal of described full-wave rectification amplifying circuit 1061 and generating circuit from reference voltage 1062, and circuit of output terminal connects the input end of described Gain Automatic adjusting amplifying circuit 103;
Weak signal suppresses circuit 1064, and the inlet circuit of this weak signal inhibition circuit 1064 connects the output terminal of described full-wave rectification amplifying circuit 1061 and generating circuit from reference voltage 1062, and circuit of output terminal connects the input end of described waveform changing circuit 104;
During the utility model work:
Laser instrument 2 ' output power is 340uW, and through 1/3 spectroscope 3 ', light beam is through polariscope 4 ', and intensity reduces 1/2, and final power is 57uW, and the difference on the frequency of laser is 3.4～4.0MHz;
Receiver detects light signal, be converted to current signal through the photodiode 1011 in the photoelectric switching circuit 101, the converting sensitivity of photodiode 1011 is 0.4A/W, and then switching current is 22.8 uA, through current/voltage-converted module 1012, obtaining sine voltage signal V1, as shown in Figure 7, is 1.2mm because photodiode 1011 receives diameter, and optical fiber output diameter is greater than 1.2mm, therefore light signal is decayed to some extent, and voltage signal is fainter, and has noise;
The sine voltage signal V1 of 102 pairs of photoelectric switching circuits of amplification filtering circuit, 101 outputs carries out amplification filtering, obtains filtered signal V3, and waveform as shown in Figure 8;
Intensity according to filtered signal V3, control signal generation circuit produces control signal: full-wave rectification amplifying circuit 1061 at first carries out full-wave rectification to signal V3 after the filtering of amplification filtering circuit 102 outputs, change sinusoidal signal into d. c. voltage signal V7, again signal is amplified; Generating circuit from reference voltage 1062 produces reference voltage REF1, REF2, REF3, REF4 by electric resistance partial pressure; Some comparers in the gain control signal generation circuit 1063 are with reference voltage REF1, REF2, REF3 and d. c. voltage signal V7 carry out hysteresis relatively, when strength signal greater than a certain reference voltage, then control signal corresponding is a high level, otherwise control signal is a low level, the gain control signal CON1 that produces, CON2, CON3 controls analog switch, thereby change the closed loop gain of Gain Automatic adjusting amplifying circuit 103, when control signal is low level, gain is 15, when control signal all is high level, gain is 2, make voltage signal amplitude stability+5V～+ scope of 10V in; Weak signal suppresses the power of circuit 1064 according to d. c. voltage signal V7, the signal output of control waveform change-over circuit 104, if d. c. voltage signal V7 amplitude is too little, also be that d. c. voltage signal V7 after the rectification is near reference voltage REF4, it is high level that the weak signal of comparer output suppresses control signal, then waveform changing circuit 104 is exported constant high level, otherwise is low level;
Adjusted sinusoidal wave V4 (waveform as shown in Figure 9) gains, comparer through waveform changing circuit 104 carries out waveform transformation, when weak signal inhibition control signal is high level, triode is opened, make the comparative voltage of the adjusted sinusoidal wave V4 of gain reduce, because the bias voltage of the adjusted sine wave signal V4 of gain is greater than comparative voltage, therefore waveform changing circuit 104 comparers are exported high level, otherwise the comparative voltage of the adjusted sine wave signal V4 that gains equals bias voltage, thereby waveform changing circuit 104 comparers are converted to square-wave signal with sinusoidal signal;
Square-wave signal is converted to differential digital signal through differential driver, and waveform as shown in figure 10.
The double-frequency laser interference signal receiver of a kind of high speed gain automatic and adjustable that the utility model provides, produce three gains and adjust the control signal drive analog switch, closure and unlatching by analog switch, change the closed loop gain of signal amplification circuit, make voltage signal amplitude stability+5V～+ scope of 10V in; Weak signal suppresses control circuit, the output waveform of control sine-square wave conversion circuit; Adopt high-speed photodiode, can reach 1GHz the response frequency of interference signal; Adopt the operational amplifier of high speed high bandwidth, so entire circuit have higher response speed and bandwidth; Gain Automatic adjusting amplifying circuit guarantees that signal can be because of saturated generation distortion in processing procedure; Weak signal suppresses circuit cut-off signals output when incident intensity is lower than certain amplitude, avoids occurring the excessive output signal of error.
Claims (6)
1. the double-frequency laser interference signal receiver of a high speed gain automatic and adjustable is characterized in that, comprises:
Photosignal change-over circuit (101);
Amplification filtering circuit (102), the inlet circuit of this amplification filtering circuit (102) connects the output terminal of described photosignal conversion circuit (101);
Gain Automatic adjusting amplifying circuit (103), the inlet circuit of this Gain Automatic amplifying circuit (103) connects the output terminal of described amplification filtering circuit (102);
Waveform changing circuit (104), the inlet circuit of this waveform changing circuit (104) connects the output terminal of described Gain Automatic adjusting amplifying circuit (103);
Differential driver (105), the inlet circuit of this differential driver (105) connects the output terminal of described waveform changing circuit (104);
Also comprise:
Control signal generation circuit, the inlet circuit of this control signal generation circuit connects the output terminal of described amplification filtering circuit (102), and output terminal circuit respectively connects the input end of described Gain Automatic adjusting amplifying circuit (103) and the input end of described waveform changing circuit (104).
2. the double-frequency laser interference signal receiver of high speed gain automatic and adjustable as claimed in claim 1 is characterized in that, described control signal generation circuit comprises:
Full-wave rectification amplifying circuit (1061);
Generating circuit from reference voltage (1062);
Gain control signal produces circuit (1061), the inlet circuit of this gain control signal generation circuit (1061) connects the output terminal of described full-wave rectification amplifying circuit (1061) and generating circuit from reference voltage (1062), and circuit of output terminal connects the input end of described Gain Automatic adjusting amplifying circuit (103);
Weak signal suppresses circuit (1064), the inlet circuit of this weak signal inhibition circuit (1064) connects the output terminal of described full-wave rectification amplifying circuit (1061) and generating circuit from reference voltage (1062), and circuit of output terminal connects the input end of described waveform changing circuit (104).
3. the double-frequency laser interference signal receiver of high speed gain automatic and adjustable as claimed in claim 1 is characterized in that, described photosignal change-over circuit comprises photodiode (1011) and the current/voltage-converted module (1012) that circuit connects.
4. the double-frequency laser interference signal receiver of high speed gain automatic and adjustable as claimed in claim 1 is characterized in that, described generating circuit from reference voltage (1062) comprises some resistance, produces reference voltage REF1, REF2, REF3 by electric resistance partial pressure.
5. the double-frequency laser interference signal receiver of high speed gain automatic and adjustable as claimed in claim 1, it is characterized in that, described gain control signal produces circuit (1063) and comprises some comparers, and reference voltage REF1, REF2, REF3 and d. c. voltage signal (V7) are carried out hysteresis relatively.
6. the double-frequency laser interference signal receiver of high speed gain automatic and adjustable as claimed in claim 1 is characterized in that, described weak signal suppresses circuit (1064) and comprises comparer, and d. c. voltage signal (V7) is compared with reference voltage REF4.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU2007201987514U CN201141770Y (en) | 2007-11-30 | 2007-11-30 | Double-frequency laser interfere signal receiver with automatically adjustable high-speed gain |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU2007201987514U CN201141770Y (en) | 2007-11-30 | 2007-11-30 | Double-frequency laser interfere signal receiver with automatically adjustable high-speed gain |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN201141770Y true CN201141770Y (en) | 2008-10-29 |
Family
ID=40069481
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNU2007201987514U Expired - Lifetime CN201141770Y (en) | 2007-11-30 | 2007-11-30 | Double-frequency laser interfere signal receiver with automatically adjustable high-speed gain |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN201141770Y (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102520375A (en) * | 2011-12-14 | 2012-06-27 | 吉林大学 | Fluxgate magnetometer detection circuit and method for improving accuracy thereof |
| CN102723998A (en) * | 2012-05-29 | 2012-10-10 | 武汉电信器件有限公司 | Control device and control method of delay interferometer working point |
| CN103890537A (en) * | 2011-08-19 | 2014-06-25 | 迈克逊诊断有限公司 | Detector circuit for interferometers |
| CN108828564A (en) * | 2018-06-29 | 2018-11-16 | 成都楼兰科技有限公司 | Laser signal receivers |
| CN112902991A (en) * | 2021-01-25 | 2021-06-04 | 上海兰宝传感科技股份有限公司 | Electromagnetic coding measurement method with automatic gain adjustment function |
-
2007
- 2007-11-30 CN CNU2007201987514U patent/CN201141770Y/en not_active Expired - Lifetime
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103890537A (en) * | 2011-08-19 | 2014-06-25 | 迈克逊诊断有限公司 | Detector circuit for interferometers |
| CN102520375A (en) * | 2011-12-14 | 2012-06-27 | 吉林大学 | Fluxgate magnetometer detection circuit and method for improving accuracy thereof |
| CN102520375B (en) * | 2011-12-14 | 2015-06-03 | 吉林大学 | Fluxgate magnetometer detection circuit and method for improving accuracy thereof |
| CN102723998A (en) * | 2012-05-29 | 2012-10-10 | 武汉电信器件有限公司 | Control device and control method of delay interferometer working point |
| CN102723998B (en) * | 2012-05-29 | 2015-06-17 | 武汉电信器件有限公司 | Control device and control method of delay interferometer working point |
| CN108828564A (en) * | 2018-06-29 | 2018-11-16 | 成都楼兰科技有限公司 | Laser signal receivers |
| CN112902991A (en) * | 2021-01-25 | 2021-06-04 | 上海兰宝传感科技股份有限公司 | Electromagnetic coding measurement method with automatic gain adjustment function |
| CN112902991B (en) * | 2021-01-25 | 2022-10-14 | 上海兰宝传感科技股份有限公司 | Electromagnetic coding measurement method with automatic gain adjustment function |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN100476364C (en) | Complete digitisation 4 quadrant detector detecting laser beam deflection angle device and method | |
| CN201141770Y (en) | Double-frequency laser interfere signal receiver with automatically adjustable high-speed gain | |
| EP0793222A3 (en) | Optical apparatus | |
| CN107816938B (en) | Circuit for automatically zeroing and modulating amplitude of interference system under low contrast and using method thereof | |
| CN100559159C (en) | The self-compensating method and apparatus of fiber gas sensor light path | |
| US6384590B1 (en) | Light receiving circuit for use in electro-optic sampling oscilloscope | |
| EP0953846A3 (en) | Electro-optic sampling oscilloscope | |
| US6426494B1 (en) | Optical signal detector and optical signal detecting method | |
| CN115372942A (en) | Echo processing circuit of laser range finder | |
| CN108534893B (en) | Photoelectric detection circuit for optical heterodyne detection | |
| US6580066B2 (en) | Measurement signal generating circuit for linear scale | |
| JP6336718B2 (en) | Autofocus device | |
| CN103674797A (en) | Sensor for particulate matter concentration detection | |
| CN115015872A (en) | Near-infrared band echo detection device for laser radar | |
| GB2162010A (en) | Level compensation circuit | |
| CN101625264B (en) | Super-large length distributed optical fiber sensing optical receiver | |
| EP3296761B1 (en) | Distance measuring device | |
| US5535044A (en) | Optical frequency mixing apparatus | |
| JPS6388871A (en) | Optical hybrid integrated circuit device | |
| CN115184907B (en) | Balance detection circuit and laser ranging system | |
| Huang et al. | The front-end electronics design for broadband high-sensitive light pulse detection | |
| CN112858805B (en) | Frequency response characteristic parameter measuring device for quadrant photoelectric detector | |
| CN101750206B (en) | Device for detecting stability of optical frame | |
| US8816267B2 (en) | DC bias evaluation in an AC coupled circuit via transient gain response | |
| JPH05196707A (en) | Optical magnetic-field sensor |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CX01 | Expiry of patent term |
Granted publication date: 20081029 |