CN108037731B - A kind of frequency difference interference signal high-resolution subdivision system of phase integral operation transform - Google Patents
A kind of frequency difference interference signal high-resolution subdivision system of phase integral operation transform Download PDFInfo
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- CN108037731B CN108037731B CN201711100065.3A CN201711100065A CN108037731B CN 108037731 B CN108037731 B CN 108037731B CN 201711100065 A CN201711100065 A CN 201711100065A CN 108037731 B CN108037731 B CN 108037731B
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- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B19/00—Programme-control systems
- G05B19/02—Programme-control systems electric
- G05B19/18—Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of programme data in numerical form
- G05B19/401—Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of programme data in numerical form characterised by control arrangements for measuring, e.g. calibration and initialisation, measuring workpiece for machining purposes
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- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B2219/00—Program-control systems
- G05B2219/30—Nc systems
- G05B2219/34—Director, elements to supervisory
- G05B2219/34242—For measurement only
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Abstract
The present invention relates to a kind of frequency difference interference signal high-resolution subdivision systems of phase integral operation transform, reference signal processing circuit, measuring signal processing circuit is respectively completed measuring signal and the Photoelectric Detection of reference signal is converted, amplification, after filtering and shaping, output is after two-way square wave digital signal, all the way be sent into phase discriminator carry out frequency multiplication debate to, output is adding with phase change, tally-down pulse signal, phase discriminator progress frequency multiplication debates the adding with phase change to output, tally-down pulse signal is sent to counter, the integer of frequency difference interference signal is sent in programmable processor by counter;Another way is input to high-resolution phase detection group again simultaneously, frequency difference interference signal is subjected to high-resolution phase detection, then the decimal of frequency difference interference signal is sent in programmable processor by bus, the pulse of calculation processing integer and fraction data are exported by bus mode.The present invention has the characteristics that measuring speed is fast, high resolution, high reliablity.
Description
Technical field
The invention belongs to photoelectric detection technology fields, are related to heterodyne ineterferometer method for detecting phases, especially a kind of application
The frequency difference interference signal high-resolution subdivision system of phase integral operation transform can be widely used for super large-scale integration processing and set
Online on-position measure, error correction and control of standby, precision machine tool etc. etc..
Background technique
Heterodyne ineterferometer is most common long range measurements instrument in industry, is widely used in various precision machine tools, big rule
In-site measurement, error correction and the control of vlsi die process equipment etc..Theoretically, if not to heterodyne interferometer output signal
It is finely divided processing, then ultimate measurement accuracy only can reach the half of optical source wavelength.With the development of nano-fabrication technique,
To measurement and the precision monitored, more stringent requirements are proposed, it is therefore necessary to carry out at high power subdivision to difference interference output signal
Reason, subdivision functional module become the core component of heterodyne ineterferometer.Traditional high power subdivision can be summarized as optics and electricity
Careful point of two ways.Since optical fine is to sacrifice interferometry speed as cost, high-subdividing number gets over high measurement speed drop
Low more, furthermore the structure of optical fine is also excessively complicated, it is difficult to realize that high power is segmented, therefore electronic fine-grained is difference interference
Major component method.And commonly the divided method principle based on phase locking frequency multiplying is measurement road and benchmark road signal locking phase times simultaneously
Frequency is handled, by obtaining double frequency pulse relevant to displacement after digital demodulation, its main feature is that, pulse after demodulation can also directly into
Enter motion control and realize high accuracy positioning control, but the frequency of frequency multiplication locking phase and the bandwidth of tracking are limited, the control of digital demodulation
It is limited by high-frequency work.And factors are also limited by based on the digital phase detection divided method for filling out pulse, therefore to measurement
The raising of precision is extremely limited.
Summary of the invention
In view of the above-mentioned defects in the prior art or insufficient, the purpose of the present invention is to provide apply phase integral operation transform
Frequency difference interference signal high-resolution subdivision system, to solve the above technical problems, which can greatly improve
The measurement accuracy of heterodyne interferometry system.
To achieve the above object the invention adopts the following technical scheme:
A kind of frequency difference interference signal high-resolution subdivision system of phase integral operation transform, including reference signal processing electricity
Road, measuring signal processing circuit, phase discriminator, high-resolution phase detection group, counter and programmable processor;At reference signal
Reason circuit, measuring signal processing circuit be respectively completed the Photoelectric Detection conversion of measuring signal and reference signal, amplification, filter with it is whole
It after shape, exports as after two-way square wave digital signal, is sent into phase discriminator all the way and carries out frequency multiplication and debate to exporting as with phase change
Add, tally-down pulse signal, phase discriminator carry out frequency multiplication debate to output with phase change plus, tally-down pulse signal is sent to
The integer of frequency difference interference signal is sent in programmable processor by counter, the counter by bus;While another way is again
It is input to high-resolution phase detection group, which carries out high-resolution phase inspection for frequency difference interference signal
It surveys, then the decimal of frequency difference interference signal is sent in programmable processor by bus, last programmable processor calculates
Show that final subdivision result is exported by bus mode after processing integer pulse and fraction data;
The high-resolution phase detection group is made of exclusive or device, integrator, integrator B, arithmetic unit, A/D converter,
The pulse signal containing phase information that exclusive or device generates enters integrator B, if when the pulse signal containing phase information
The voltage that duty ratio increases the output of integrator B just increases therewith, while being sent into fortune together with the reference voltage of integrator A output
Device is calculated, which carries out scale operation output for the voltage of the output of two integrators, and it is sent into A/D converter and is converted,
Be then fed into programmable processor completion decimal adds operation, then remakes next comparison loop;
When the voltage of output that the duty ratio of the pulse signal containing phase information reduces integrator B just reduces therewith, together
When be sent into arithmetic unit together with the reference voltage of integrator A output, which carries out the voltage of the output of two integrators
Scale operation output is sent into A/D converter and is converted, and be then fed into programmable processor completion decimal subtracts operation, then
Next comparison loop is remake, counter exports integer pulse into subsequent programmable place by bus in real time in this process
Device is managed, final programmable processor exports high-resolution phase detection result.
Wherein subdivision measurement accuracy calculation formula is as follows:
Wherein, n is analog-to-digital conversion digit, and the n=16 in present example, then final precision is λ/65536
(0.005nm), n are positive integer.
Phase discriminator and counter realize number system;Decimal number system is realized in high-resolution phase detection, may be programmed place
Reason device completes integer and high resolution detection is realized in the output of progressively increasing of decimal.
As a further solution of the present invention, measuring signal processing circuit is by photoelectric conversion circuit, operational amplification circuit, filter
Wave circuit, shaping circuit composition, the optical signal of photoelectric conversion circuit receiving instrument output simultaneously convert thereof into electric signal, and operation is put
Big circuit is used to amplify photoelectric conversion circuit output electric signal, it is made to meet subsequent conditioning circuit processing requirement, filter circuit
For filtering out the high-frequency noise in signal, shaping circuit is used to for the sinusoidal signal that filter circuit exports being shaped as to be suitble to digitizer
The digital pulse signal of part processing.
The beneficial effects of the present invention are: 1) the frequency difference interference signal high-resolution of the invention using phase integral operation transform
Subdivision system, the processing of utilization exclusive or and integral transformation of use, which combine, realizes that voltage then will by arithmetic unit with phase
The voltage progress scale operation of the output of two integrators is output to A/D converter and is converted, to realize high-resolution phase
Position subdivision;Subdivision accuracy can be made to be determined by the digit of analog-to-digital conversion, so that subdivision accuracy is substantially increased, so that of the invention
Meet the requirement of Precision Machining field application;
2) of the invention to be realized using high-speed digital circuit, than traditional subdivision system with higher stability and reliably
Property;Have the characteristics that measuring speed is fast, high resolution, high reliablity;Can be widely used for super large-scale integration process equipment,
Online on-position measure, error correction and control of precision machine tool etc. etc..
Detailed description of the invention
Fig. 1 is the frequency difference interference signal high-resolution subdivision system structural schematic diagram of phase integral operation transform of the present invention;
Fig. 2 is the schematic illustration that measuring signal of the invention pre-processes circuit;
Fig. 3 is high-resolution phase detection group schematic illustration of the invention.
Figure label: reference signal processing circuit 1, measuring signal photoelectric conversion 2, phase discriminator 3, high-resolution phase detection
Group 4, counter 5, programmable processor 6, photoelectric conversion circuit 7, amplifying circuit 8, filter circuit 9, shaping circuit 10, exclusive or device
11, integrator A 12, integrator B 13, arithmetic unit 14, A/D converter 15.
Specific embodiment
The present invention is further elaborated in the following with reference to the drawings and specific embodiments.
As shown in Figure 1, a kind of frequency difference interference signal high-resolution subdivision system of phase integral operation transform, including reference letter
Number processing circuit 1, measuring signal processing circuit 2, phase discriminator 3, high-resolution phase detection group 4, counter 5 and programmable processing
Device 6;Reference signal processing circuit 1, measuring signal processing circuit 2 are respectively completed measuring signal and the Photoelectric Detection of reference signal turns
After changing, amplify, filtering with shaping, exports and carry out frequency multiplication after two-way square wave digital signal, to be sent into phase discriminator 3 and debate to exporting and be
With phase change plus, tally-down pulse signal, phase discriminator 3 carry out frequency multiplication debate to output with phase change plus, tally-down
Pulse signal is sent to counter 5, which is sent to programmable processor for the integer of frequency difference interference signal by bus
In 6;It is input to high-resolution phase detection group 4 again simultaneously, which carries out frequency difference interference signal high
The decimal of frequency difference interference signal, is then sent in programmable processor 6 by bus, can finally be compiled by resolution phase detection
Show that final subdivision result is exported by bus mode after 6 calculation processing integer pulse of thread processor and fraction data.
Wherein subdivision measurement accuracy calculation formula is as follows:
Wherein, n is analog-to-digital conversion digit, and the n=16 in present example, then final precision is λ/65536
(0.005nm), n are positive integer.
Phase discriminator 3 and counter 5 realize number system;Decimal number system is realized in high-resolution phase detection 4, may be programmed
Processor 6 completes integer and high resolution detection is realized in the output of progressively increasing of decimal, it can accurately high-resolution to measure heterodyne
The period of interferometer signal and phase information.
As shown in Fig. 2, measuring signal processing circuit 2 is by photoelectric conversion circuit 7, operational amplification circuit 8, filter circuit 9, whole
Shape circuit 10 forms, and the optical signal of 7 receiving instrument of photoelectric conversion circuit output simultaneously converts thereof into electric signal, operational amplification circuit
8 amplify for exporting electric signal to photoelectric conversion circuit 7, so that it is met subsequent conditioning circuit processing requirement, filter circuit 9 is used for
The high-frequency noise in signal is filtered out, shaping circuit 10 is used to for the sinusoidal signal that filter circuit exports being shaped as to be suitble to digital device
The digital pulse signal of processing.Reference signal processing circuit 1 is identical as above-mentioned working principle process not affected to be repeated.
As shown in figure 3, the high-resolution phase detection group 4 by exclusive or device 11, integrator A 12, integrator B 13,
Arithmetic unit 14, A/D converter 15 form, and the pulse signal containing phase information that exclusive or device 11 generates enters integrator B 13,
Increase therewith if increasing the voltage of output of integrator B 13 if the duty ratio of the pulse signal containing phase information, simultaneously
It is sent into arithmetic unit 14 together with the reference voltage that integrator A 12 is exported, the arithmetic unit 14 is by the voltage of the output of two integrators
Scale operation output is carried out, A/D converter is sent into and is converted, be then fed into the completion decimal of programmable processor 6 adds operation,
Then next comparison loop is remake;
When the voltage of output that the duty ratio of the pulse signal containing phase information reduces integrator B 13 just reduces therewith,
It is sent into arithmetic unit 14 together with the reference voltage that integrator A 12 is exported simultaneously, the arithmetic unit 14 is by the output of two integrators
Voltage carries out scale operation output, is sent into A/D converter and is converted, and is then fed into programmable processor 6 and completes subtracting for decimal
Then operation remakes next comparison loop, after counter 5 exports integer pulse entrance by bus in real time in this process
Continuous programmable processor 6, final programmable processor 6 export high-resolution phase detection result.
The above is present pre-ferred embodiments, for the ordinary skill in the art, according to the present invention
Introduction, in the case where not departing from the principle of the present invention and spirit, changes, modifications, replacement and change that embodiment is carried out
Type is still fallen within protection scope of the present invention.
Claims (4)
1. a kind of frequency difference interference signal high-resolution subdivision system of phase integral operation transform, which is characterized in that believe including reference
Number processing circuit, measuring signal processing circuit, phase discriminator, high-resolution phase detection group, counter and programmable processor;Ginseng
Examine signal processing circuit, measuring signal processing circuit is respectively completed measuring signal and the Photoelectric Detection of reference signal conversion, amplification,
After filtering is with shaping, exports and carry out frequency multiplication after two-way square wave digital signal, to be sent into phase discriminator all the way and debate to exporting as with phase
Variation plus, tally-down pulse signal, phase discriminator carry out frequency multiplication debate to output with phase change plus, tally-down pulse signal
It is sent to counter, which is sent to the integer of frequency difference interference signal in programmable processor by bus;It is another simultaneously
It is input to high-resolution phase detection group again all the way, which carries out high-resolution for frequency difference interference signal
Then the decimal of frequency difference interference signal is sent in programmable processor by phase-detection by bus, finally may be programmed processing
Show that final subdivision result is exported by bus mode after device calculation processing integer pulse and fraction data;
The high-resolution phase detection group is made of exclusive or device, integrator A, integrator B, arithmetic unit, A/D converter, different
Or the pulse signal containing phase information that device generates enters integrator B, if accounting for when the pulse signal containing phase information
The voltage of output of the sky than increasing integrator B just increases therewith, while being sent into operation together with the reference voltage of integrator A output
The voltage of the output of two integrators is carried out scale operation output by device, the arithmetic unit, is sent into A/D converter and is converted, so
That is sent into programmable processor completion decimal afterwards adds operation, then remakes next comparison loop;When the arteries and veins containing phase information
The voltage for the output that the duty ratio for rushing signal reduces integrator B just reduces therewith, while the reference voltage one with integrator A output
Play feeding arithmetic unit, which carries out scale operation output for the voltage of the output of two integrators, be sent into A/D converter into
Row conversion, be then fed into programmable processor completion decimal subtracts operation, next comparison loop is then remake, in this process
Middle counter exports integer pulse by bus in real time and enters subsequent programmable processor, and final programmable processor exports high score
The phase detection result of resolution.
2. the frequency difference interference signal high-resolution subdivision system of phase integral operation transform according to claim 1, feature
It is, segments measurement accuracy calculation formula:
Wherein, n is analog-to-digital conversion digit, and n=16, then final precision is λ/65536 (0.005nm), and n is positive integer.
3. the frequency difference interference signal high-resolution subdivision system of phase integral operation transform according to claim 1, feature
It is, phase discriminator and counter realize number system;Decimal number system, programmable processor are realized in high-resolution phase detection
High resolution detection is realized in the output of progressively increasing for completing integer and decimal.
4. the frequency difference interference signal high-resolution subdivision system of phase integral operation transform according to claim 1, feature
It is, measuring signal processing circuit is made of photoelectric conversion circuit, operational amplification circuit, filter circuit, shaping circuit, and photoelectricity turns
It changes the optical signal of circuit receiving instrument output and converts thereof into electric signal, operational amplification circuit is used for defeated to photoelectric conversion circuit
Electric signal amplifies out, so that it is met subsequent conditioning circuit processing requirement, filter circuit is used to filter out the high-frequency noise in signal, whole
Shape circuit is used to be shaped as the sinusoidal signal that filter circuit exports to be suitble to the digital pulse signal of digital device processing.
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CN112212783B (en) * | 2020-09-21 | 2021-11-05 | 清华大学 | Phase discrimination system and method based on dynamic response time measurement method |
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