Displacement measurement method, system and device and readable storage medium

Abstract

The invention relates to a displacement measurement method, system and device and a readable storage medium, and the method comprises the steps: determining a plurality of phase sequences with orthogonal characteristics, and transmitting the phase sequences to a modulator, thereby enabling the modulator to carry out the phase modulation of a received reference light signal according to the phase sequences, obtaining a plurality of modulation signals, and transmitting the modulation signals to an optical splitter; receiving a plurality of interference signals sent by the optical splitter; performing coherence analysis on the plurality of interference signals to obtain a coherence measurement result; determining time delay and phase difference corresponding to the detection light signal and the echo signal according to a coherence measurement result; determining an initial displacement measurement result corresponding to the target detection object according to the time delay, and determining a displacement correction amount according to the phase difference; and performing displacement correction on the initial displacement measurement result through the displacement correction amount to obtain a target displacement measurement result. The problem that in the prior art, the displacement measurement precision and the measurement range cannot be considered at the same time is solved, and large-range and high-precision displacement measurement is achieved.

Description

Technical Field

[0001] The present application relates to the field of distance measurement technology, and in particular to a displacement measurement method, system, device, and readable storage medium. Background Art

[0002] Since its inception, laser ranging technology has played a vital role in precision manufacturing, scientific research, aerospace, and other fields. However, the rapid development of modern industry and technology has placed higher demands on ranging technology, especially in applications such as high-end equipment manufacturing, spacecraft docking, and large-scale engineering construction, which require both nanometer-level high-precision measurements and a measurement range of several kilometers. However, traditional laser interferometry ranging methods struggle to reconcile the contradiction between accuracy and range. Improving measurement accuracy is often limited by the coherence length of the laser, while expanding the measurement range leads to a decrease in accuracy.

[0003] There is currently no effective solution to the problem of difficulty in balancing displacement measurement accuracy and measurement range in related technologies. Summary of the Invention

[0004] Based on this, it is necessary to provide a displacement measurement method, system, device and readable storage medium to address the above technical problems.

[0005] In a first aspect, the present application provides a displacement measurement method, which is applied to a displacement measurement system, the system including a beam splitter, a spectrometer, a modulator, and a controller; the method comprising:

[0006] Determining a plurality of phase sequences having orthogonal characteristics, and sending the plurality of phase sequences to the modulator so that the modulator performs phase modulation processing on a received reference optical signal according to the plurality of phase sequences to obtain a plurality of modulated signals, and sending the plurality of modulated signals to an optical splitter; wherein the reference optical signal is determined after the beam splitter performs optical splitting processing on a received preset reference light source;

[0007] Receive multiple interference signals sent by the optical splitter; wherein the multiple interference signals are determined by the optical splitter using the multiple modulation signals to perform interference processing on the received echo signal and the reference light signal; the echo signal is determined by the detection light signal reflected by the target detection object to the optical splitter; the detection light signal and the reference light signal are determined by the beam splitter performing spectroscopic processing on the received target light source;

[0008] performing coherence analysis on the plurality of interference signals to obtain a coherence measurement result;

[0009] Determining the time delay and phase difference corresponding to the detection light signal and the echo signal according to the coherence measurement result;

[0010] determining an initial displacement measurement result corresponding to the target detection object according to the time delay, and determining a displacement correction amount according to the phase difference;

[0011] The initial displacement measurement result is subjected to displacement correction using the displacement correction amount to obtain a target displacement measurement result corresponding to the target detection object.

[0012] In one embodiment, the reference optical signal includes a first reference optical signal and a second reference optical signal; the phase sequence includes a first phase sequence and a second phase sequence having an orthogonal characteristic; the modulator includes a first modulator and a second modulator; and the sending of the plurality of phase sequences to the modulator so that the modulator performs phase modulation processing on the received reference optical signal according to the plurality of phase sequences to obtain a plurality of modulated signals includes:

[0013] sending the first phase sequence to the first modulator, so that the first modulator performs phase modulation processing on the received first reference optical signal according to the first phase sequence to obtain a first modulated signal;

[0014] sending the second phase sequence to the second modulator, so that the second modulator performs phase modulation processing on the received second reference optical signal according to the second phase sequence to obtain a second modulated signal;

[0015] The first modulation signal and the second modulation signal are determined as a plurality of the modulation signals.

[0016] In one embodiment, the system further includes a delay device; the modulator further includes a third modulator;

[0017] The delayer is used to delay the received first modulated signal to obtain a first delayed signal; or the delayer is used to delay the received second modulated signal to obtain a second delayed signal;

[0018] The third modulator is used to phase modulate the first delayed signal to obtain a third modulated signal; or, the third modulator is used to phase modulate the second delayed signal to obtain a fourth modulated signal; or, the third modulator is used to phase modulate the first modulated signal to obtain a fifth modulated signal; or, the third modulator is used to phase modulate the second modulated signal to obtain a sixth modulated signal.

[0019] In one embodiment, the optical splitter includes a first sub-optical splitter and a second sub-optical splitter; and receiving a plurality of interference signals sent by the optical splitter includes:

[0020] receiving a first interference signal sent by the first sub-splitter, and receiving a second interference signal sent by the second sub-splitter;

[0021] determining the first interference signal and the second interference signal as a plurality of interference signals;

[0022] The first interference signal is determined after the first sub-splitter performs interference processing on the received reference optical signal and the first modulated signal; the second interference signal is determined after the second sub-splitter performs interference processing on the received echo signal and the fourth modulated signal;

[0023] Alternatively, the first interference signal is determined after the first sub-splitter performs interference processing on the received reference optical signal and the fifth modulated signal; and the second interference signal is determined after the second sub-splitter performs interference processing on the received echo signal and the second delayed signal;

[0024] Alternatively, the first interference signal is determined after the first sub-splitter performs interference processing on the received reference optical signal and the first delayed signal; the second interference signal is determined after the second sub-splitter performs interference processing on the received echo signal and the sixth modulated signal;

[0025] Alternatively, the first interference signal is determined after the first sub-splitter performs interference processing on the received reference optical signal and the third modulated signal; the second interference signal is determined after the second sub-splitter performs interference processing on the received echo signal and the second modulated signal.

[0026] In one embodiment, the interference signal includes a first interference signal and a second interference signal; and performing coherence analysis on the plurality of interference signals to obtain a coherence measurement result includes:

[0027] performing differential processing on the first interference signal and the second interference signal respectively to obtain a first differential signal and a second differential signal;

[0028] performing a multiplication operation on the first differential signal and the second differential signal to obtain a first correlation result;

[0029] performing a periodic inner product operation on the first correlation result to obtain a second correlation result;

[0030] Perform spectrum analysis on the second correlation result to obtain corresponding amplitude measurement results and phase measurement results.

[0031] In one embodiment, the coherence measurement result includes an amplitude measurement result and a phase measurement result; and determining the time delay and phase difference corresponding to the detection light signal and the echo signal based on the coherence measurement result includes:

[0032] determining, based on the amplitude measurement result, coherence envelope functions corresponding to the detection light signal and the echo signal;

[0033] Extracting an envelope peak value of the coherence envelope function, and determining a delay corresponding to the envelope peak value as a time delay corresponding to the detection light signal and the echo signal;

[0034] Determining a phase difference function corresponding to the detection light signal and the echo signal according to the phase measurement result;

[0035] The phase difference between the detection light signal and the echo signal is determined according to the phase difference function and the delay corresponding to the envelope peak.

[0036] In one embodiment, determining the initial displacement measurement result corresponding to the target detection object according to the time delay, and determining the displacement correction amount according to the phase difference, includes:

[0037] Multiplying the time delay by the speed of light to obtain an initial displacement measurement result corresponding to the target detection object;

[0038] Get the wavelength corresponding to the target light source;

[0039] A displacement correction amount is determined according to the wavelength and the phase difference; the accuracy of the displacement correction amount is greater than the accuracy of the initial displacement measurement result.

[0040] In a second aspect, the present application further provides a displacement measurement system for implementing the displacement measurement method described in any one of the embodiments of the first aspect above; the system includes a beam splitter, an optical splitter, a modulator, and a controller; wherein the beam splitter is used to perform optical splitting processing on a received target light source and a preset reference light source to obtain a detection light signal and a reference signal corresponding to the target light source, and a reference light signal corresponding to the preset reference light source; the modulator is used to perform phase modulation processing on the reference light signal according to a plurality of the phase sequences to obtain a plurality of modulated signals, and send the plurality of the modulated signals to the optical splitter; the optical splitter is used to perform interference processing on the received echo signal and the reference light signal respectively using the plurality of the modulated signals to obtain respective corresponding interference signals; the echo signal is the detection light signal, determined by being reflected by the target detection object to the optical splitter;

[0041] The controller is also used to implement the steps of the method described in any one of the embodiments of the first aspect above.

[0042] In a third aspect, the present application further provides a displacement measuring device, comprising a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the steps of the method described in any one of the embodiments of the first aspect are implemented.

[0043] In a fourth aspect, the present application further provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the method described in any one of the embodiments of the first aspect above.

[0044] In a fifth aspect, the present application also provides a computer program product, including a computer program, which implements the steps of the method described in any one of the above embodiments when executed by a processor.

[0045] The above-mentioned displacement measurement method, system, device and readable storage medium use multiple phase sequences with orthogonal characteristics to phase modulate the reference light signal, and use multiple modulation signals to interfere with the received echo signal and the reference light signal respectively, thereby obtaining multiple interference signals; by performing coherence analysis on these interference signals, not only can the time delay and phase difference between the detection light signal and the echo signal be accurately determined, thereby obtaining the initial displacement measurement result of the target detection object, but the displacement correction amount can also be further calculated based on the phase difference to correct the initial measurement result, and ultimately achieve high-precision target displacement measurement of the target detection object; avoid the problem in traditional technology that cannot take into account the accuracy and measurement range of displacement measurement at the same time, improve the accuracy and reliability of displacement measurement, realize large-scale high-precision unified measurement, and have good environmental adaptability and engineering practicality. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the technical solutions in the embodiments of the present application or related technologies, the following briefly introduces the drawings required for use in the embodiments of the present application or related technical descriptions. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying any creative work.

[0047] Figure 1 Schematic diagram of the structure of a displacement measurement system in one embodiment;

[0048] Figure 2 1 is a flow chart of a displacement measurement method according to an embodiment;

[0049] Figure 3 FIG. 1 is a flow chart of a step of determining a coherence measurement result in one embodiment;

[0050] Figure 4 FIG. 1 is a flow chart of the step of determining time delay and phase difference in one embodiment;

[0051] Figure 5 Schematic diagram of a coherence envelope function in one embodiment;

[0052] Figure 6 Schematic diagram of a phase difference function in one embodiment;

[0053] Figure 7 A schematic diagram of the relationship between phase and delay in one embodiment;

[0054] Figure 8 is a structural schematic diagram of a displacement measurement system in a specific embodiment;

[0055] Figure 9 FIG. 4 is a diagram showing the internal structure of a displacement measuring device in one embodiment. DETAILED DESCRIPTION

[0056] In order to make the purpose, technical solutions and advantages of this application more clear, the following further describes this application in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0057] Since its inception, laser ranging technology has played a vital role in precision manufacturing, scientific research, aerospace, and other fields. The rapid development of modern industry and technology has placed increasingly stringent demands on the accuracy, range, and reliability of ranging technology. This is particularly true in areas such as high-end equipment manufacturing, spacecraft docking, and large-scale engineering construction, where both nanometer-level high-precision measurement and a multi-kilometer measurement range are required. This presents unprecedented challenges for ranging technology.

[0058] Although traditional laser interferometry ranging technology can achieve nanometer-level measurement accuracy, its measurement range is limited by the laser coherence length and has strict requirements on environmental conditions, making it difficult to be widely used in actual engineering. Although pulse time-of-flight ranging technology can achieve measurement over a larger range, its accuracy can generally only reach the millimeter level, which is difficult to meet the needs of high-precision measurement. In response to the problem in related technologies that it is difficult to balance displacement measurement accuracy and measurement range, that is, there is a problem that improving measurement accuracy often leads to a reduction in measurement range, while expanding measurement range will reduce measurement accuracy, the present application provides a displacement measurement method applied to a displacement measurement system.

[0059] In an exemplary embodiment, Figure 1 As shown, Figure 1Schematic diagram of the structure of a displacement measurement system in one embodiment; the displacement measurement system includes a beam splitter 100, a beam splitter 200, a modulator 300 and a controller 400; wherein the beam splitter 100 is used to perform a splitting process on the received target light source and the preset reference light source to obtain a detection light signal and a reference signal corresponding to the target light source, and a reference light signal corresponding to the preset reference light source; the controller 400 is used to determine a plurality of phase sequences with orthogonal characteristics and send the plurality of phase sequences to the modulator 300 (the phase sequence sending path is not shown in the figure); the modulator 400 is used to perform a phase modulation process on the reference light signal according to the plurality of phase sequences to obtain a plurality of modulated signals, and send the plurality of modulated signals to the beam splitter The optical spectrometer 200 is used to perform interference processing on the received echo signal and the reference optical signal respectively using multiple modulation signals to obtain respective corresponding interference signals; the echo signal is a detection optical signal, which is determined by being reflected by the target detection object to the optical spectrometer 200; the controller 400 is also used to perform coherence analysis on the multiple interference signals to obtain coherence measurement results; based on the coherence measurement results, the time delay and phase difference corresponding to the detection light signal and the echo signal are determined; based on the time delay, the initial displacement measurement result corresponding to the target detection object is determined, and based on the phase difference, the displacement correction amount is determined; the initial displacement measurement result is displacement corrected by the displacement correction amount to obtain the target displacement measurement result corresponding to the target detection object.

[0060] The beam splitter 100 includes a first beam splitter and a second beam splitter. The first beam splitter is configured to perform optical splitting on a received target light source to obtain a detection light signal and a reference light signal corresponding to the target light source. The detection light signal and the reference light signal are located on different optical paths. The target light source can be, but is not limited to, a pulsed laser, a fiber laser, a semiconductor laser, a frequency comb, or a supercontinuum light source, and is not specifically limited herein.

[0061] Among them, the second beam splitter is used to perform spectroscopic processing on the received preset reference light source to obtain a corresponding reference light signal, wherein the reference light signal includes a first reference light signal and a second reference light signal; wherein, the preset reference light source is an ordinary coherent light source, which can be but is not limited to a classical light field, a continuous wave, and a pulsed light field, and is not specifically limited here.

[0062] Understandably, traditional methods rely on quantum entangled light sources, making them extremely difficult to implement. This embodiment uses a conventional coherent light source as the reference light, significantly reducing the complexity. Conventional coherent light sources, such as classical light fields, are much easier to obtain than quantum entangled light sources, effectively reducing system complexity.

[0063] The modulator 300 is used to implement phase modulation processing on multiple optical field signals based on multiple phase sequences with orthogonal characteristics. The modulator 300 may include, but is not limited to, an electro-optical phase modulator, which is not specifically limited here.

[0064] It can be understood that since each phase sequence is unique and orthogonal to other phase sequences, each modulated signal carries unique information. Even if the signals interfere and overlap during transmission, they can be separated based on their unique phase sequence characteristics.

[0065] The optical splitter 200 includes a first sub-splitter and a second sub-splitter. The first and second sub-splitters can be 50 / 50 splitters, which is not specifically defined here. The first sub-splitter is used to implement interferometric mixing between the reference optical signal and the modulated signal, while the second sub-splitter is used to implement interferometric mixing between the echo signal and the modulated signal. It should be understood that the modulated signals involved in the interferometric processing by the first and second sub-splitters are different, depending on the internal structure of the modulator 300, which is not specifically defined here.

[0066] The controller 400 is provided with a DSP (Digital Signal Processor) for implementing signal analysis and processing.

[0067] The phase sequence can be, but is not limited to, a pseudo-random binary sequence or an m-sequence, which is not specifically limited here; the phase sequence includes a first phase sequence and a second phase sequence, and the first phase sequence and the second phase sequence have strict orthogonality; for example, the first phase sequence is recorded as , the second phase sequence is recorded as , the first phase sequence and the second phase sequence , the cross-correlation within the period is zero, that is: ; The first phase sequence λ(1) and the second phase sequence , the autocorrelation has an ideal pulse characteristic, namely: .

[0068] It should be noted that the multiple phase sequences may be generated by the controller 400 or may be generated by an external terminal and then transmitted to the controller 400 , which is not specifically limited here.

[0069] It should be noted that the interference measurement system or displacement measurement system in traditional technology has a phase insensitivity problem under long baseline conditions, that is, high-precision coherence measurement cannot be achieved under long baseline conditions, and thus accurate phase information cannot be provided; the displacement measurement system of this embodiment, based on multiple phase sequences with orthogonal characteristics, lays the foundation for the system to effectively separate signals in the subsequent signal processing stage, improve the signal-to-noise ratio, and achieve greater measurement contrast; based on a preset reference light source, there is no need to establish a complex quantum entanglement network, which effectively reduces the complexity of the displacement measurement system and lays the foundation for further improving the applicability of the displacement measurement system; by performing coherence analysis on multiple interference signals, corresponding coherence measurement results are obtained, which can provide an accurate and complete coherence function (including amplitude information and phase information); based on this, the system can accurately extract and distinguish light field phase information from different paths, so that high-precision light field coherence measurement can still be achieved under long baseline conditions, greatly expanding the application scope and reliability of displacement measurement, effectively avoiding the phase insensitivity problem of related technologies under long baseline conditions, and laying the foundation for achieving large-scale, high-precision displacement measurement.

[0070] The displacement measurement system in this embodiment has a compact structure, is easy to implement in engineering, is applicable to static and dynamic measurement scenarios, and the measurement process is completed automatically without manual intervention, with low maintenance costs, good system stability, and can achieve real-time measurement with fast response speed.

[0071] In one embodiment, Figure 2 As shown, Figure 2 FIG. 1 is a flow chart of a displacement measurement method in one embodiment; the displacement measurement method is applied to the displacement measurement system described in the above embodiment, and the displacement measurement method includes the following steps:

[0072] In step S201, a plurality of phase sequences with orthogonal characteristics are determined and sent to a modulator so that the modulator performs phase modulation processing on a received reference optical signal according to the plurality of phase sequences to obtain a plurality of modulated signals, which are then sent to an optical splitter.

[0073] The functions of the components in the position measurement system are the same as those described in the above embodiment and will not be described in detail here.

[0074] The phase sequence can be, but is not limited to, a pseudo-random binary sequence, an m-sequence, or a programmable sequence, and is not specifically limited here. The phase sequence includes a first phase sequence and a second phase sequence, and the first phase sequence and the second phase sequence are strictly orthogonal. It should be noted that the multiple phase sequences can be generated by the controller or generated by an external terminal and transmitted to the controller, and are not specifically limited here.

[0075] The reference light signal is determined after a beam splitter (i.e., a second beam splitter in the beam splitter) performs spectroscopic processing on a received preset reference light source. The reference light signal includes a first reference light signal and a second reference light signal. The preset reference light source is an ordinary coherent light source and can be, but is not limited to, a classical light field, a continuous wave, or a pulsed light field, and is not specifically limited thereto.

[0076] Understandably, traditional methods rely on quantum entangled light sources, making them extremely difficult to implement. This embodiment uses a conventional coherent light source as the reference light, significantly reducing the complexity. Conventional coherent light sources, such as classical light fields, are much easier to obtain than quantum entangled light sources, effectively reducing system complexity.

[0077] Step S202: receiving a plurality of interference signals sent by the optical splitter.

[0078] Among them, multiple interference signals are determined after the spectrometer uses multiple modulation signals to perform interference processing on the received echo signal and reference light signal respectively; the echo signal is determined when the detection light signal is reflected from the target detection object to the spectrometer; the detection light signal and the reference light signal are determined after the beam splitter (i.e., the first beam splitter in the beam splitter) performs spectroscopic processing on the received target light source.

[0079] It can be understood that since each phase sequence is unique and orthogonal to other sequences, each modulated signal carries unique information. Even if the signals interfere and overlap during transmission, they can be separated based on their unique phase sequence characteristics.

[0080] Step S203: performing coherence analysis on the multiple interference signals to obtain a coherence measurement result.

[0081] The coherence measurement results include amplitude measurement results and phase measurement results. The amplitude measurement results are used to characterize the intensity characteristics of the signal; the phase measurement results are used to characterize the temporal or spatial relationship between signals.

[0082] Step S204: determining the time delay and phase difference corresponding to the detection light signal and the echo signal according to the coherence measurement result.

[0083] The time delay between the detection light signal and the echo signal refers to the time interval between the detection light signal being emitted to the target detection object and the echo signal being returned, that is, the flight time.

[0084] In another exemplary embodiment, the time delay between the probe light signal and the echo signal can be determined by recording the time using a timer. Specifically, after the probe light signal is emitted from the first beam splitter and reaches the target object, it is reflected to form an echo signal, which is then received by the second sub-beam splitter. By starting a timer at the moment the probe light signal is emitted and stopping the timer at the moment the echo signal is received, the time interval between the emission and return of the probe light signal, i.e., the time delay, can be directly measured.

[0085] The phase difference refers to the phase difference between the detection light signal and the echo signal at the time delay.

[0086] It should be noted that since the displacement measurement system of the present application can provide complete coherence measurement results (including amplitude and phase) under long baseline conditions, it can accurately determine the phase difference corresponding to the detection light signal and the echo signal, laying a data foundation for realizing displacement correction.

[0087] Step S205 : determining an initial displacement measurement result corresponding to the target detection object according to the time delay, and determining a displacement correction amount according to the phase difference.

[0088] It can be understood that time delay refers to the flight time corresponding to the detection light signal. Based on this time delay, combined with the speed of light , the initial displacement measurement result corresponding to the target detection object can be calculated.

[0089] The displacement correction is used to achieve higher-precision correction based on the initial displacement measurement. It's understandable that the accuracy of the displacement correction is higher than that of the initial displacement measurement. Phase difference correction essentially leverages the interference effect of light to amplify tiny displacements into a detectable phase signal, thus surpassing the resolution limit of time-of-flight ranging.

[0090] Step S206 , performing displacement correction on the initial displacement measurement result using the displacement correction amount to obtain a target displacement measurement result corresponding to the target detection object.

[0091] It should be noted that the initial displacement measurement results, due to limitations such as pulse width, have relatively low ranging accuracy, providing only an approximate distance and failing to provide nanometer- to millimeter-level accuracy. However, this embodiment, based on the initial displacement measurement results, incorporates a displacement correction to perform a displacement correction on the initial displacement measurement results. This not only avoids the distance ambiguity associated with phase-based ranging (i.e., due to the periodic nature of the phase, it can only directly determine distance within a wavelength range, making long-distance measurement impossible), but also maintains the wide-range advantage of the pulse-based ranging method, achieving high-precision, wide-range displacement measurement.

[0092] The above-mentioned displacement measurement method uses multiple phase sequences with orthogonal characteristics to phase modulate the reference light signal, and uses multiple modulation signals to interfere with the received echo signal and the reference light signal respectively, thereby obtaining multiple interference signals; by performing coherence analysis on these interference signals, not only can the time delay and phase difference between the detection light signal and the echo signal be accurately determined, thereby obtaining the initial displacement measurement result of the target detection object, but the displacement correction amount can also be further calculated based on the phase difference to correct the initial measurement result, and finally achieve high-precision target displacement measurement of the target detection object; avoids the problem in traditional technology that cannot take into account both the accuracy and measurement range of displacement measurement at the same time, improves the accuracy and reliability of displacement measurement, realizes large-scale high-precision unified measurement, and has good environmental adaptability and engineering practicality.

[0093] In one embodiment, the modulator 300 includes a first modulator and a second modulator; sending multiple phase sequences to the modulators so that the modulators perform phase modulation processing on the received reference optical signal according to the multiple phase sequences to obtain multiple modulated signals includes the following steps:

[0094] Step 1: Send a first phase sequence to a first modulator, so that the first modulator performs phase modulation processing on a received first reference optical signal according to the first phase sequence to obtain a first modulated signal.

[0095] Step 2: Send the second phase sequence to the second modulator, so that the second modulator performs phase modulation processing on the received second reference optical signal according to the second phase sequence to obtain a second modulated signal.

[0096] Step 3: Determine the first modulation signal and the second modulation signal as a plurality of modulation signals.

[0097] Among them, the first modulator and the second modulator can be but are not limited to electro-optical modulators, which are used to perform preliminary phase modulation processing on the first reference optical signal and the second reference optical signal based on the first phase sequence and the second phase sequence with orthogonal characteristics to obtain the first modulated signal and the second modulated signal, ensure that the first modulated signal and the second modulated signal are independent of each other in the phase space, reduce interference between the signals, and improve the efficiency and accuracy of information transmission.

[0098] In this embodiment, by using a first modulator and a second modulator to perform preliminary phase modulation processing on a first reference optical signal and a second reference optical signal having orthogonal characteristics, the generated first modulated signal and the second modulated signal are ensured to be independent of each other in phase space, effectively reducing interference between the signals and improving the efficiency and accuracy of information transmission.

[0099] In one embodiment, the displacement measurement system further includes a delay device 500; the modulator 300 further includes a third modulator;

[0100] The delayer 500 is used to perform delay processing on the received first modulated signal to obtain a first delayed signal; or, the delayer 500 is used to perform delay processing on the received second modulated signal to obtain a second delayed signal.

[0101] The delay device 500 may, but is not limited to, adopt a piezoelectric ceramic telescopic mirror structure with a resolution of up to 0.1 nm, and needs to be set according to the actual needs of signal interference, which is not specifically limited here.

[0102] It can be understood that the delay device 500 is used to introduce a controllable time delay to obtain a complete and accurate coherence measurement result.

[0103] The third modulator is used to phase modulate the first delayed signal to obtain a third modulated signal; or, the third modulator is used to phase modulate the second delayed signal to obtain a fourth modulated signal; or, the third modulator is used to phase modulate the first modulated signal to obtain a fifth modulated signal; or, the third modulator is used to phase modulate the second modulated signal to obtain a sixth modulated signal.

[0104] The third modulator is an adjustable phase modulator for introducing a controllable phase change. It is understood that the third modulator can apply a precise phase offset to the first delayed signal, the second delayed signal, the first modulated signal, or the second modulated signal. The phase offset can be dynamically adjusted based on, but is not limited to, a PID control algorithm.

[0105] For example, Figure 1 Taking this as an example, the delayer 500 is used to delay the received second modulated signal to obtain a second delayed signal; the third modulator is used to phase modulate the second delayed signal to obtain a fourth modulated signal.

[0106] It is understandable that the delayer 500 and the third modulator may be configured in any of the aforementioned various implementations, and need to be configured according to actual needs, and are not specifically limited herein.

[0107] In this embodiment, the delay device 500 can introduce a controllable time delay, laying the foundation for realizing coherence measurement; the third modulator, as an adjustable phase modulator, can impose a precise phase offset on the first delayed signal, or the second delayed signal, or the first modulated signal, or the second modulated signal, laying the foundation for realizing phase measurement of the correlation function, and this phase offset can be dynamically adjusted through methods such as PID control algorithm to adapt to different application requirements; at the same time, based on the different settings of the delay device 500 and the third modulator, the flexibility and adaptability of the system are effectively improved.

[0108] In one embodiment, the optical splitter 200 includes a first sub-splitter and a second sub-splitter; receiving a plurality of interference signals sent by the optical splitter includes the following steps:

[0109] Step 1: Receive a first interference signal sent by a first sub-splitter, and receive a second interference signal sent by a second sub-splitter.

[0110] Step 2: determine the first interference signal and the second interference signal into multiple interference signals.

[0111] The first interference signal is determined by the first sub-splitter performing interference processing on the received reference optical signal and the first modulated signal; the second interference signal is determined by the second sub-splitter performing interference processing on the received echo signal and the fourth modulated signal;

[0112] Alternatively, the first interference signal is determined after the first sub-splitter performs interference processing on the received reference optical signal and the fifth modulated signal; the second interference signal is determined after the second sub-splitter performs interference processing on the received echo signal and the second delayed signal;

[0113] Alternatively, the first interference signal is determined after the first sub-splitter performs interference processing on the received reference optical signal and the first delayed signal; the second interference signal is determined after the second sub-splitter performs interference processing on the received echo signal and the sixth modulated signal;

[0114] Alternatively, the first interference signal is determined after the first sub-splitter performs interference processing on the received reference optical signal and the third modulated signal; the second interference signal is determined after the second sub-splitter performs interference processing on the received echo signal and the second modulated signal.

[0115] For example, Figure 1 For example, the first interference signal is determined by the first sub-splitter performing interference processing on the received reference optical signal and the first modulated signal; the second interference signal is determined by the second sub-splitter performing interference processing on the received echo signal and the fourth modulated signal.

[0116] In this embodiment, based on the first sub-splitter and the second sub-splitter, multiple modulation signals are implemented to perform interference mixing processing on the reference optical signal and the echo signal, respectively, laying the foundation for achieving coherence measurement and obtaining complete coherence measurement results.

[0117] In one embodiment, Figure 3 As shown, Figure 3 Schematic diagram of a flow chart of steps for determining a coherence measurement result in one embodiment; performing coherence analysis on multiple interference signals to obtain a coherence measurement result includes the following steps:

[0118] Step S301 : performing differential processing on the first interference signal and the second interference signal respectively to obtain a first differential signal and a second differential signal.

[0119] It can be understood that performing differential processing on the first interference signal and the second interference signal respectively can eliminate common mode noise and improve the signal-to-noise ratio.

[0120] Step S302 : performing a multiplication operation on the first differential signal and the second differential signal to obtain a first correlation result.

[0121] Step S303: Perform a periodic inner product operation on the first correlation result to obtain a second correlation result.

[0122] The first correlation result primarily reflects the direct cross-correlation between the two interfering signals and is the basis for understanding the interaction between the signals. The second correlation result, based on this, integrates the first correlation result to remove noise and stabilize the signal, providing high-quality data support for the final spectrum analysis and coherence measurement.

[0123] Step S304: Perform spectrum analysis on the second correlation result to obtain corresponding amplitude measurement results and phase measurement results.

[0124] The coherence measurement results include amplitude measurement results and phase measurement results. The amplitude measurement results are used to characterize the intensity characteristics of the signal, and the phase measurement results are used to characterize the temporal or spatial relationship between the signals. Exemplarily, the amplitude measurement results include an intensity correlation function.

[0125] In an exemplary embodiment, the displacement measurement system further includes a first detector and a second detector; the controller 400 includes a first subtractor, a second subtractor, a multiplier, an integrator, and a signal processor;

[0126] The first subtractor and the second subtractor are used to execute step S301; the multiplier is used to execute step S302; the integrator is used to execute step S303; and the signal processor is used to execute step S304.

[0127] The first detector and the second detector may be, but are not limited to, photoelectric detectors, configured to receive the corresponding interference signal and convert the interference signal into an electrical signal for subsequent signal processing based on the controller 400. It is understood that the first detector and the second detector are electrically connected to the controller 400.

[0128] In this embodiment, differential processing of the received interference signals effectively eliminates common-mode noise and improves the signal-to-noise ratio. The first correlation result reflects the direct cross-correlation between the two interference signals, laying the foundation for understanding the interaction between the signals. The second correlation result provides high-quality data support for the final spectrum analysis and coherence measurement, ensuring clear and reliable measurement results even in complex environments.

[0129] In one embodiment, Figure 4 As shown, Figure 4 A flow chart of the steps for determining time delay and phase difference in one embodiment; the coherence measurement results include amplitude measurement results and phase measurement results; and determining the time delay and phase difference corresponding to the detection light signal and the echo signal based on the coherence measurement results includes the following steps:

[0130] Step S401: Determine the coherence envelope function corresponding to the detection light signal and the echo signal according to the amplitude measurement result.

[0131] Among them, the coherence envelope function is used to characterize the mutual coherence between the detection light signal and the echo signal.

[0132] Step S402 : extracting the envelope peak of the coherence envelope function, and determining the delay corresponding to the envelope peak as the time delay corresponding to the detection light signal and the echo signal.

[0133] The peak value of the coherence envelope function corresponds to the time point of optimal alignment between the two signals, that is, the time delay, which is the time interval between the emission of the detection light signal and the reception of the echo signal.

[0134] Step S403: determining the phase difference function corresponding to the detection light signal and the echo signal according to the phase measurement result.

[0135] The phase difference function is used to characterize how the phase difference between the detection light signal and the echo signal changes over time.

[0136] Step S404: determining the phase difference between the detection light signal and the echo signal according to the phase difference function and the delay corresponding to the envelope peak.

[0137] Among them, the phase difference can provide higher distance resolution than simple time delay, and is used to accurately correct the initial displacement measurement result, that is, the rough distance measurement result.

[0138] In an exemplary embodiment, by dynamically adjusting the delay time of the delay device and the phase modulation θ of the third modulator, the relationship between the intensity correlation function and the phase modulation θ under different delay conditions can be obtained. Based on the relationship between the intensity correlation function and the phase modulation θ under different delay conditions, a curve of the relationship between the intensity correlation function and the phase modulation θ under each delay condition is fitted to obtain a target fitting function. Furthermore, the amplitude of each target fitting function is extracted to obtain multiple target amplitudes, and the coherence envelope function is obtained based on the multiple target amplitudes. The phase term of each target fitting function is extracted to obtain multiple target phase terms, and the phase difference function is determined based on the multiple target phase terms.

[0139] Among them, the expression of the target fitting function is: ;in, is the bias term, is the amplitude, is the phase difference, and θ is the phase of the third modulator.

[0140] Among them, the coherence envelope function reflects the mutual coherence between the detection light signal and the echo signal, which is used to indicates; when When , it means that the detection light signal and the echo signal have strong coherence under the delay T; when When it approaches 0, it means that the coherence between the detection light signal and the echo signal gradually weakens or even disappears.

[0141] In another exemplary embodiment, the phase difference function may be determined by observing the zero point position of the waveform, calculating the phase offset relative to the time T=0 μs, and obtaining the phase difference function under different delays.

[0142] For example, see Figure 5 , Figure 5 Schematic diagram of a coherence envelope function in one embodiment; Figure 5 The ordinate represents the amplitude of the intensity correlation function, and the abscissa represents the delay T; see Figure 6 , Figure 6 Schematic diagram of a phase difference function in one embodiment; Figure 6 The ordinate represents the phase, and the abscissa represents the delay T; specifically, extract Figure 5 The envelope peak value of the coherence envelope function is determined, and the delay corresponding to the envelope peak value is determined as the time delay corresponding to the detection light signal and the echo signal; and then according to Figure 6 The phase difference function in and the delay corresponding to the envelope peak can determine the phase difference between the detection light signal and the echo signal.

[0143] In an exemplary embodiment, see Figure 7 , Figure 7 shows the relationship between phase and delay, Figure 7 The ordinate represents the phase, and the abscissa represents the delay T, wherein the yellow intensity is higher than the blue intensity.

[0144] In this embodiment, a coherence envelope function is constructed based on the amplitude, and the time delay is determined by its envelope peak. Then, the phase difference function is calculated using the phase measurement results, and the phase difference is accurately located in combination with the time delay. This lays the foundation for improving ranging accuracy. Displacement measurement is achieved based on the phase difference and time delay, which not only avoids the problem of distance ambiguity but also effectively expands the measurement range.

[0145] In one embodiment, determining an initial displacement measurement result corresponding to a target detection object according to a time delay and determining a displacement correction amount according to a phase difference includes the following steps:

[0146] Step 1: Multiply the time delay by the speed of light to obtain the initial displacement measurement result corresponding to the target detection object.

[0147] The initial displacement measurement result is a rough distance measurement result.

[0148] Step 2: Obtain the wavelength corresponding to the target light source.

[0149] The wavelength of the target light source ranges from visible light to near infrared.

[0150] Step 3: Determine the displacement correction amount based on the wavelength and phase difference.

[0151] The accuracy of the displacement correction is greater than that of the initial displacement measurement result. The accuracy of the initial displacement measurement result can reach the meter to kilometer level, while the accuracy of the displacement correction can reach the nanometer to millimeter level.

[0152] For example, the time delay is recorded as τ, the initial displacement measurement result corresponding to the target detection object is recorded as D, the phase difference is recorded as θ, and the displacement correction amount is recorded as ; Delay the time Multiplying by the speed of light, we get the initial displacement measurement result corresponding to the target detection object, that is, Where c is the speed of light. Assuming the wavelength of the target light source is λ, the displacement correction amount is determined based on the wavelength λ and the phase difference θ. .

[0153] Furthermore, based on the displacement correction , perform displacement correction on the initial displacement measurement result D corresponding to the target detection object, and obtain the target displacement measurement result corresponding to the target detection object: .

[0154] In this embodiment, the initial displacement measurement result D is obtained by multiplying the time delay with the speed of light, and a high-precision displacement correction value is calculated based on the wavelength and phase difference. , and ultimately achieves accurate displacement measurement of the target detection object, avoiding the problem in traditional technology that cannot take into account both the accuracy and measurement range of displacement measurement at the same time, improving the accuracy and reliability of displacement measurement, and achieving large-scale, high-precision unified measurement, with good environmental adaptability and engineering practicality.

[0155] The above displacement measurement method has high measurement accuracy, with a coarse ranging accuracy better than 0.1mm and a fine ranging accuracy of nanometers. It also has a large measurement range and can measure distances of several kilometers. It has strong anti-interference ability, good real-time performance, and strong adaptability, and can be used in complex measurement environments. It can meet the measurement needs of multiple fields, such as precision manufacturing measurement, aerospace positioning, engineering deformation monitoring, intelligent equipment positioning, scientific experiment measurement, medical device positioning, transportation monitoring, etc.

[0156] In one embodiment, see Figure 8 The target light source is a pulsed laser, and the preset reference light source is a continuous laser; the first beam splitter is used to perform spectroscopic processing on the received pulsed laser to obtain a detection light signal and a reference light signal, and send the detection light signal to the target detection object, and send the reference light signal to the first sub-splitter; the second beam splitter is used to perform spectroscopic processing on the received continuous laser to obtain a first reference light signal and a second reference light signal, and send the first reference light signal to the first modulator, so that the first modulator uses a first phase sequence to phase-modulate the first reference light signal to obtain a first modulated signal; the second reference light signal is sent to the second modulator, so that the second modulator uses a second phase sequence orthogonal to the first phase sequence to phase-modulate the second reference light signal to obtain a second modulated signal; the delayer is used to delay the received second modulated signal to obtain a second delayed signal; the third modulator is used to phase modulate the second delayed signal to obtain a fourth modulated signal; the first sub-splitter is used to perform interference processing on the reference light signal and the first modulated signal to obtain a first interference signal; the second sub-splitter is used to perform interference processing on the echo signal and the fourth modulated signal to obtain a second interference signal.

[0157] Furthermore, a subtractor is used to perform differential processing on the first interference signal and the second interference signal, respectively, to obtain a first differential signal and a second differential signal; a multiplier is used to multiply the first differential signal and the second differential signal to obtain a first correlation result; an integrator is used to perform a periodic inner product operation on the first correlation result to obtain a second correlation result; finally, a signal processor is used to perform spectrum analysis on the second correlation result to obtain a coherence measurement result; wherein the coherence measurement result includes an amplitude measurement result and a phase measurement result. Based on the coherence measurement result, the time delay and phase difference corresponding to the detection light signal and the echo signal are determined; the initial displacement measurement result corresponding to the target detection object is determined based on the time delay, and the displacement correction amount is determined based on the phase difference; the initial displacement measurement result is displacement-corrected using the displacement correction amount to obtain a target displacement measurement result corresponding to the target detection object.

[0158] It is understandable that the interference measurement system or displacement measurement system in traditional technology has a phase insensitivity problem under long baseline conditions, that is, high-precision coherence measurement cannot be achieved under long baseline conditions, and thus accurate phase information cannot be provided; the displacement measurement system of the above embodiment, based on multiple phase sequences with orthogonal characteristics, lays the foundation for the system to effectively separate signals in the subsequent signal processing stage, improve the signal-to-noise ratio, and achieve greater measurement contrast; based on a preset reference light source, there is no need to establish a complex quantum entanglement network, which effectively reduces the complexity of the displacement measurement system and lays the foundation for further improving the applicability of the displacement measurement system; by performing coherence analysis on multiple interference signals, corresponding coherence measurement results are obtained, which can provide an accurate and complete coherence function (including amplitude information and phase information); based on this, the system can accurately extract and distinguish light field phase information from different paths, so that high-precision light field coherence measurement can still be achieved under long baseline conditions, greatly expanding the application scope and reliability of displacement measurement, effectively avoiding the phase insensitivity problem of related technologies under long baseline conditions, and laying the foundation for achieving large-scale, high-precision displacement measurement.

[0159] It should be understood that, although the various steps in the flowcharts involved in the various embodiments described above are displayed in sequence according to the instructions of the arrows, these steps are not necessarily executed in sequence in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order restriction on the execution of these steps, and these steps can be executed in other orders. Moreover, at least a portion of the steps in the flowcharts involved in the various embodiments described above can include multiple steps or multiple stages, and these steps or stages are not necessarily executed and completed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a portion of steps or stages in other steps.

[0160] In an exemplary embodiment, a displacement measuring device is provided. The displacement measuring device may be a server, and its internal structure may be as shown in FIG. Figure 9 As shown. The displacement measuring device includes a processor, a memory, an input / output interface (Input / Output, abbreviated as I / O) and a communication interface. The processor, memory and input / output interface are connected through a system bus, and the communication interface is connected to the system bus through the input / output interface. The processor of the displacement measuring device is used to provide computing and control capabilities. The memory of the displacement measuring device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operation of the operating system and computer program in the non-volatile storage medium. The database of the displacement measuring device is used to store displacement measurement related data. The input / output interface of the displacement measuring device is used to exchange information between the processor and an external device. The communication interface of the displacement measuring device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, a displacement measurement method is implemented.

[0161] Those skilled in the art will understand that Figure 9 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the displacement measuring device to which the solution of the present application is applied. The specific displacement measuring device may include more or fewer components than shown in the figure, or combine certain components, or have a different component arrangement.

[0162] In one embodiment, a displacement measuring device is further provided, including a memory and a processor. The memory stores a computer program, and the processor implements the steps in the above method embodiments when executing the computer program.

[0163] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps in the above-mentioned method embodiments are implemented.

[0164] In one embodiment, a computer program product is provided, including a computer program, which implements the steps in the above method embodiments when executed by a processor.

[0165] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of relevant data must comply with relevant regulations.

[0166] Those skilled in the art will understand that all or part of the processes in the above-mentioned embodiments can be implemented by instructing the relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. In particular, any reference to memory, database, or other media used in the embodiments provided in this application can include at least one of non-volatile memory and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The databases involved in the various embodiments provided herein may include at least one of a relational database and a non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the various embodiments provided herein may be, but are not limited to, general-purpose processors, central processing units (CPUs), graphics processing units (GPUs), digital signal processors (DSPs), programmable logic devices (PLDs), quantum computing-based data processing logic devices, artificial intelligence (AI) processors, and the like.

[0167] The technical features of the above embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this application.

[0168] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present application shall be determined by the appended claims.

Claims

1. A displacement measurement method, characterized in that: Applied to a displacement measurement system, the system includes a beam splitter, a spectrometer, a modulator, and a controller; the method includes: Determining a plurality of phase sequences having orthogonal characteristics, and sending the plurality of phase sequences to the modulator so that the modulator performs phase modulation processing on a received reference optical signal according to the plurality of phase sequences to obtain a plurality of modulated signals, and sending the plurality of modulated signals to an optical splitter; wherein the reference optical signal is determined after the beam splitter performs optical splitting processing on a received preset reference light source; Receive multiple interference signals sent by the optical splitter; wherein the multiple interference signals are determined by the optical splitter using the multiple modulation signals to perform interference processing on the received echo signal and the reference light signal; the echo signal is determined by the detection light signal reflected by the target detection object to the optical splitter; the detection light signal and the reference light signal are determined by the beam splitter performing spectroscopic processing on the received target light source; performing coherence analysis on the plurality of interference signals to obtain a coherence measurement result; Determining the time delay and phase difference corresponding to the detection light signal and the echo signal according to the coherence measurement result; determining an initial displacement measurement result corresponding to the target detection object according to the time delay, and determining a displacement correction amount according to the phase difference; The initial displacement measurement result is subjected to displacement correction using the displacement correction amount to obtain a target displacement measurement result corresponding to the target detection object.

2. The method according to claim 1, characterized in that The reference optical signal includes a first reference optical signal and a second reference optical signal; the phase sequence includes a first phase sequence and a second phase sequence having an orthogonal characteristic; the modulator includes a first modulator and a second modulator; The step of sending the plurality of phase sequences to the modulator so that the modulator performs phase modulation processing on the received reference optical signal according to the plurality of phase sequences to obtain a plurality of modulated signals includes: sending the first phase sequence to the first modulator, so that the first modulator performs phase modulation processing on the received first reference optical signal according to the first phase sequence to obtain a first modulated signal; sending the second phase sequence to the second modulator, so that the second modulator performs phase modulation processing on the received second reference optical signal according to the second phase sequence to obtain a second modulated signal; The first modulation signal and the second modulation signal are determined as a plurality of the modulation signals.

3. The method according to claim 2, characterized in that The system further includes a delay device; the modulator further includes a third modulator; The delayer is used to delay the received first modulated signal to obtain a first delayed signal; or the delayer is used to delay the received second modulated signal to obtain a second delayed signal; The third modulator is used to phase modulate the first delayed signal to obtain a third modulated signal; or, the third modulator is used to phase modulate the second delayed signal to obtain a fourth modulated signal; or, the third modulator is used to phase modulate the first modulated signal to obtain a fifth modulated signal; or, the third modulator is used to phase modulate the second modulated signal to obtain a sixth modulated signal.

4. The method according to claim 3, characterized in that The optical splitter includes a first sub-optical splitter and a second sub-optical splitter; and receiving a plurality of interference signals sent by the optical splitter includes: receiving a first interference signal sent by the first sub-splitter, and receiving a second interference signal sent by the second sub-splitter; determining the first interference signal and the second interference signal as a plurality of interference signals; The first interference signal is determined after the first sub-splitter performs interference processing on the received reference optical signal and the first modulated signal; the second interference signal is determined after the second sub-splitter performs interference processing on the received echo signal and the fourth modulated signal; Alternatively, the first interference signal is determined after the first sub-splitter performs interference processing on the received reference optical signal and the fifth modulated signal; and the second interference signal is determined after the second sub-splitter performs interference processing on the received echo signal and the second delayed signal; Alternatively, the first interference signal is determined after the first sub-splitter performs interference processing on the received reference optical signal and the first delayed signal; the second interference signal is determined after the second sub-splitter performs interference processing on the received echo signal and the sixth modulated signal; Alternatively, the first interference signal is determined after the first sub-splitter performs interference processing on the received reference optical signal and the third modulated signal; the second interference signal is determined after the second sub-splitter performs interference processing on the received echo signal and the second modulated signal.

5. The method according to any one of claims 1 to 4, characterized in that: The interference signal includes a first interference signal and a second interference signal; and performing coherence analysis on the plurality of interference signals to obtain a coherence measurement result includes: performing differential processing on the first interference signal and the second interference signal respectively to obtain a first differential signal and a second differential signal; performing a multiplication operation on the first differential signal and the second differential signal to obtain a first correlation result; performing a periodic inner product operation on the first correlation result to obtain a second correlation result; Perform spectrum analysis on the second correlation result to obtain corresponding amplitude measurement results and phase measurement results.

6. The method according to any one of claims 1 to 4, characterized in that: The coherence measurement result includes an amplitude measurement result and a phase measurement result; and determining the time delay and phase difference corresponding to the detection light signal and the echo signal based on the coherence measurement result includes: determining, based on the amplitude measurement result, coherence envelope functions corresponding to the detection light signal and the echo signal; Extracting an envelope peak value of the coherence envelope function, and determining a delay corresponding to the envelope peak value as a time delay corresponding to the detection light signal and the echo signal; Determining a phase difference function corresponding to the detection light signal and the echo signal according to the phase measurement result; The phase difference between the detection light signal and the echo signal is determined according to the phase difference function and the delay corresponding to the envelope peak.

7. The method according to any one of claims 1 to 4, characterized in that: Determining the initial displacement measurement result corresponding to the target detection object according to the time delay, and determining the displacement correction amount according to the phase difference, includes: Multiplying the time delay by the speed of light to obtain an initial displacement measurement result corresponding to the target detection object; Get the wavelength corresponding to the target light source; A displacement correction amount is determined according to the wavelength and the phase difference; the accuracy of the displacement correction amount is greater than the accuracy of the initial displacement measurement result.

8. A displacement measurement system, characterized in that: Used to implement the displacement measurement method described in any one of claims 1 to 7; the system includes a beam splitter, a spectrometer, a modulator and a controller; wherein, The beam splitter is used to perform light splitting processing on the received target light source and the preset reference light source to obtain a detection light signal and a reference signal corresponding to the target light source, and a reference light signal corresponding to the preset reference light source; The controller is configured to determine a plurality of phase sequences having an orthogonal characteristic and send the plurality of phase sequences to the modulator; The modulator is configured to perform phase modulation processing on the reference optical signal according to the multiple phase sequences to obtain multiple modulated signals, and send the multiple modulated signals to the optical splitter; The optical splitter is used to perform interference processing on the received echo signal and the reference optical signal respectively using the multiple modulation signals to obtain respective corresponding interference signals; the echo signal is the detection light signal, which is determined by being reflected by the target detection object to the optical splitter; The controller is further configured to perform coherence analysis on the plurality of interference signals to obtain a coherence measurement result; determine, based on the coherence measurement result, a time delay and a phase difference corresponding to the detection light signal and the echo signal; determine, based on the time delay, an initial displacement measurement result corresponding to the target detection object, and determine a displacement correction amount based on the phase difference; and perform displacement correction on the initial displacement measurement result using the displacement correction amount to obtain a target displacement measurement result corresponding to the target detection object.

9. A displacement measuring device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

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