Integrated Michelson optical frequency scale and displacement measurement system based on pyramid array feedback

Abstract

The invention discloses an integrated Michelson optical frequency scale and displacement measurement system based on pyramid array feedback. The device comprises a Michelson optical frequency standard system (optical frequency standard system for short) and a Michelson displacement measurement system (displacement measurement system for short), and the optical frequency standard system and the displacement measurement system share the same reference arm. According to the invention, quantum spectral lines are used as absolute frequency reference to generate stable and accurate optical frequency standard signals, and the optical frequency standard signals are used as the reference of displacement measurement to realize organic unification of time frequency and displacement measurement; an optical frequency signal output by the optical frequency standard system has a relatively strong anti-interference capability to an external environment, and the resolution of the displacement measurement system can be improved; in order to solve the interference problem of the pitching inclination angle of a measuring arm cavity mirror in displacement measurement and tiny movement in the non-displacement measurement direction, the invention provides a reflecting mirror adopting an integrated pyramid array as a composite cavity, so that the stability and the robustness of a displacement measurement system can be improved, and the measurement range and the measurement resolution are optimized.

Description

Technical Field

[0001] This invention belongs to the field of laser technology, specifically relating to an integrated Michelson optical frequency standard and displacement measurement system with pyramidal array feedback. Background Technology

[0002] Both time and length belong to the seven fundamental physical quantities in the International System of Units (SI), and their benchmark reproduction and value transfer technologies form the cornerstone of modern industrial manufacturing, scientific research, and precision measurement. In the macroscopic spatiotemporal dimension, spatiotemporal measurement is unified: the International Committee for Weights and Measures (CIPM) has decided that the speed of light constant c (c=299,792,458 m / s) is the benchmark for spatiotemporal value conversion, enabling equivalent conversion between the length unit "meter" and the time unit "second".

[0003] However, in modern metrology, time (frequency) and length (displacement) measurement systems often operate independently based on different mechanisms. For timekeeping systems, the standard is defined as 1 second equal to... 133 The transition time between the two hyperfine levels of the Cs ground state is 9,192,631,770 times that of the Cs ground state. Based on this, current systems often utilize the transition spectral lines of atoms and molecules in the microwave or optical frequency bands. Among these, time-frequency systems in the optical frequency band, also known as optical frequency standards, theoretically achieve superior frequency stability due to their dominant frequency being 4-5 orders of magnitude higher than microwave frequency standards, making them a current research hotspot in the time-frequency field. For displacement measurement systems, these mainly include laser interferometers and X-ray crystal diffraction, which can achieve sub-nanometer and even better displacement resolution. For example, laser interferometers utilize the principle of laser interference to extract displacement information from the changes in the brightness of interference fringes, achieving displacement resolution on the order of 0.1 nm, and are widely used in lithography machine stage positioning and precision machine tool calibration. X-ray crystal diffraction, based on Bragg's law, uses the lattice constant as a natural scale to achieve displacement analysis under synchrotron radiation, and is widely used in semiconductor heterojunction interface analysis and quantum device characterization.

[0004] Achieving the organic unity of spatiotemporal systems has profound scientific significance and application value. On the one hand, with the development of high-precision manufacturing equipment such as extreme ultraviolet lithography machines and atomic force microscopes, higher demands are placed on the performance of displacement measurement systems. Currently, time (frequency) is the physical quantity with the highest measurement accuracy, and its stability and uncertainty have exceeded 10⁻¹. 9 The magnitude of displacement measurement is significant. If time-frequency signals can be used as the benchmark for displacement measurement, or if displacement measurements can be converted into time-frequency measurements, the resolution of displacement measurements could be greatly improved. On the other hand, the deep integration of spatiotemporal systems will also greatly promote the development of fields such as gravitational wave detection, relativity verification, and Earth science observation.

[0005] Patent ZL202210393703.X proposes a Michelson laser and a displacement measurement method, employing a composite resonant cavity structure with a common-gain medium, including a fixed reference arm and a movable measuring arm. The reference arm provides a frequency reference, and the cavity length of the measuring arm varies with the displacement to be measured. The system uses the relationship between laser frequency and cavity length Δν / ν=dL / L to deduce the displacement by monitoring the frequency change. However, in practice, due to mechanical vibration and environmental interference, the laser frequency within the reference arm is not stable, exhibiting frequency drift and mode hopping phenomena. Due to the lack of accurate frequency / displacement reference, it is difficult to obtain accurate displacement information solely based on the laser frequency, and it may even fail to function properly. Furthermore, the measuring arm cavity mirror described in the patent inevitably experiences pitch and tilt angles and slight movements in non-displacement measurement directions as it moves with the target under test, resulting in the following adverse effects: 1) The reflected light from the measuring arm cavity mirror cannot return to the gain medium via the original optical path, altering the light intensity distribution pattern and causing severe energy loss within the cavity. The larger the cavity length of the measuring arm, the more pronounced this adverse effect becomes, thus affecting the displacement measurement range; 2) The uneven pumping of the laser into the gain medium affects the stability of the laser wavelength, thereby impacting the displacement measurement resolution. Summary of the Invention

[0006] To address the limitations of existing Michelson lasers and displacement measurement systems, which lack an absolutely accurate reference and suffer from limited range and resolution, this invention proposes an integrated Michelson optical frequency standard and displacement measurement system with pyramidal array feedback. This system comprises two main parts: a Michelson optical frequency standard system (hereinafter referred to as the optical frequency standard system) and a Michelson displacement measurement system (hereinafter referred to as the displacement measurement system). The optical frequency standard system simultaneously shares the reference arm of the displacement measurement system. This invention utilizes quantum spectral lines as an absolute frequency reference to generate a stable and accurate optical frequency standard signal, which serves as the reference for displacement measurement, achieving an organic unity between time-frequency and displacement measurements. The optical frequency signal output by the optical frequency standard system exhibits strong anti-interference capabilities against external environmental factors, enhancing the resolution of the displacement measurement system. To address the interference issues caused by the pitch angle of the measuring arm cavity mirror and minute movements in non-displacement measurement directions during displacement measurement, this invention proposes using an integrated pyramidal array as the reflector of the composite cavity, which improves the stability and robustness of the displacement measurement system and optimizes the measurement range and resolution.

[0007] The novelty and inventiveness of the integrated Michelson optical frequency standard and displacement measurement system with pyramidal array feedback provided by this invention are reflected in the following aspects: 1. This invention achieves the organic integration of spatiotemporal systems. Within an integrated structure, by using quantum spectral lines as absolute frequency references, a stable and reliable optical frequency standard signal is first realized for use as a time-frequency reference. Simultaneously, this optical frequency standard system also provides a reference for the displacement measurement system, used to calibrate frequency changes in displacement measurements. 2. This invention uses the more stable optical frequency signal output by the optical frequency standard system, rather than the laser signal under free movement, as the frequency reference of the displacement measurement system. This can suppress the frequency drift of the reference arm caused by external environmental interference and improve the resolution of the displacement measurement system. 3. This invention uses an integrated pyramidal array as the cavity mirror of the composite cavity, which is simple in structure, easy to implement and has a long service life. The integrated design can suppress the interference caused by the pitch angle of the cavity mirror and the small movement in the non-displacement measurement direction, thereby improving the range and displacement measurement resolution of the displacement measurement system.

[0008] The technical solution provided by this invention is as follows: An integrated Michelson optical frequency standard and displacement measurement system with pyramidal array feedback includes: a Michelson optical frequency standard system (hereinafter referred to as the optical frequency standard system) and a Michelson displacement measurement system (hereinafter referred to as the displacement measurement system). The optical frequency standard system shares a reference arm with the displacement measurement system, including a laser gain medium, a first beam splitter module, a first frequency selection module, a second beam splitter module, piezoelectric ceramics, and a first pyramidal array. In addition to the reference arm, the optical frequency standard system also includes a frequency locking module, a frequency shifter, a first semi-reflective mirror, and a quantum reference and servo locking module. In addition to the reference arm, the displacement measurement system also includes a measurement arm and a detection module. The measurement arm and the reference arm share the same laser gain medium and the first beam splitter module. The measurement arm also includes a second frequency selection module, a third beam splitter module, and a second pyramidal array. The detection module includes a second semi-reflective mirror, a total reflection mirror, a beam combiner module, a detector, and a data processing module. The laser gain medium outputs a broadband fluorescence signal, providing gain for the optical frequency standard system and the displacement measurement system; The first beam splitting module includes a first half-wave plate and a first polarizing beam splitter. The first polarizing plate is used to change the polarization direction of the beam, and the first polarizing beam splitter can reflect and transmit the beam according to the polarization direction of the incident light. The two work together to split the incident light. For light incident from the direction of the laser gain medium, it is split into two beams by the first beam splitting module: reflected light and incident light. The reflected light enters the reference arm, and the transmitted light enters the measurement arm. The first frequency selection module is used to select the laser frequency within the reference arm. The first frequency selection module can use macroscopic components such as interference filters, gratings, Fabry-Polo resonators, etc., or microscopic components such as Faraday anomalous dispersion atomic filters, Focke atomic filters, etc. The second beam splitting module includes a second half-wave plate and a second polarizing beam splitter. The second polarizing plate is used to change the polarization direction of the beam, and the second polarizing beam splitter can reflect and transmit the beam according to the polarization direction of the incident light. The two work together to split the incident light; one path of transmission reaches the first pyramidal array, and one path of reflection reaches the frequency locking module. The first pyramidal array can reflect the light transmitted by the second beam-splitting module back to the laser gain medium in its original direction, realizing the oscillation of the beam between the laser gain medium and the first pyramidal array, forming a frequency of The laser; The piezoelectric ceramic is bonded to the first pyramidal array with adhesive. By changing the driving voltage of the piezoelectric ceramic, the stroke of the piezoelectric ceramic can be changed, thereby adjusting the laser frequency within the reference arm. ; The frequency locking module includes a frequency shifter, a first half-reflective lens, and a quantum reference and servo locking module. The frequency shifter can be a frequency-shiftable element such as an electro-optic modulator or an acousto-optic modulator, used to control the laser frequency. The first half-reflective lens splits the incident beam into two paths: transmitted light and reflected light. The reflected light enters the quantum reference and servo locking module, and the transmitted light enters the detection module. The quantum reference and servo locking module contains stable frequency references such as atomic and molecular spectral lines. By comparing the difference between the incident laser frequency and the frequency reference, an error signal is generated and fed back to the controller of the frequency shifter, thereby locking the laser frequency to the frequency corresponding to the reference spectral line. The second frequency selection module is used to select the laser frequency of the measuring arm. The second frequency selection module can use macroscopic components such as interference filters, gratings, Fabry-Polo resonators, etc., or microscopic components such as Faraday anomalous dispersive atom filters, etc. The third beam splitting module includes a third half-wave plate and a third polarizing beam splitter. The third polarizing plate is used to change the polarization direction of the beam, and the third polarizing beam splitter can reflect and transmit the beam according to the polarization direction of the incident light. The two work together to split the incident light; one path is transmitted to the second pyramidal array, and one path is reflected into the detection module. The second pyramidal array is fixed to the target and is used to reflect the incident beam back to the laser gain medium in its original direction, thereby achieving oscillation of the beam between the laser gain medium and the second pyramidal array, forming a laser beam. ; The detection module includes a second half-reflecting lens, a total reflection mirror, a beam combiner module, a detector, and a data processing module. The second half-reflecting lens can split the light beam transmitted from the first half-reflecting lens into two paths: a reflected path and a transmitted path. The transmitted light is the output of the optical frequency standard system and is used as a time and frequency reference. The reflected light enters the beam combiner module. The total reflection mirror can reflect the laser reflected by the third polarization beam splitter into the beam combining module; The beam combining module includes a fourth half-wave plate, a fifth half-wave plate, and a fourth polarization beam splitter. The fourth half-wave plate is used to adjust the polarization direction of the light reflected by the total reflection mirror, ensuring that it is completely transmitted through the fourth polarization beam splitter. The fifth half-wave plate is used to adjust the polarization direction of the light reflected by the second half-reflecting mirror, ensuring that it is completely reflected through the fourth polarization beam splitter, thereby combining the two laser beams. The combined laser beam then enters the detector. The detector is capable of receiving lasers output from the reference arm system. With the laser inside the measuring arm And can read the frequency difference between the two. ; The data processing module is capable of receiving and analyzing the frequency difference obtained by the detector. The change in the displacement is calculated and the displacement is extracted.

[0009] Preferably, the first pyramid array and the second pyramid array are triangular pyramids, and the pyramidal surfaces of the triangular pyramid array are composed of triangular pyramid arrays.

[0010] Preferably, the pyramidal facets of the triangular pyramidal array are composed of a regular triangular pyramid array, wherein the three lateral faces of each regular triangular pyramid are mutually perpendicular isosceles right triangles, and the base is an equilateral triangle.

[0011] Preferably, the outer surface of the pyramidal array is coated with a high-reflectivity film.

[0012] Preferably, the reflection wavelength of the coating of the pyramidal array is the same as the center wavelength of the laser output from the laser gain medium.

[0013] Compared with the prior art, the positive effects of the present invention are as follows: First, this invention achieves the organic integration of spatiotemporal systems. Using quantum spectral lines as the absolute frequency reference, a stable and reliable optical frequency standard system is constructed and directly applied to time and frequency references. Simultaneously, this optical frequency standard system also provides a high-precision reference for displacement measurement, accurately calibrating frequency changes during the displacement measurement process. Second, this invention uses the highly stable optical frequency signal output by the optical frequency standard system to replace the freely rotating laser signal as the frequency reference for displacement measurement. This invention effectively suppresses frequency drift of the reference arm caused by external environmental interference, thereby significantly improving the resolution of the displacement measurement system. Furthermore, this invention uses an integrated pyramidal array as the cavity mirror of the composite cavity. Through integrated design, it effectively suppresses interference caused by the pitch angle and minute movements of the cavity mirror in non-measurement directions, further extending the range of the displacement measurement system and improving the resolution of displacement measurements. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the integrated Michelson optical frequency standard and displacement measurement system with pyramidal array feedback proposed in this invention.

[0015] Figure 2 This is a schematic diagram of the integrated Michelson optical frequency standard and displacement measurement system with pyramidal array feedback proposed in this invention, used for displacement measurement.

[0016] Figure 3 This is a schematic diagram of the measuring arm cavity of the integrated Michelson optical frequency standard and displacement measurement system with pyramidal array feedback proposed in this invention, when the displacement in the non-measurement direction is generated.

[0017] Figure 4 This is a schematic diagram showing the change in pitch angle of the measuring arm endoscope of the integrated Michelson optical frequency standard and displacement measurement system with pyramidal array feedback proposed in this invention.

[0018] Figure 5 This is a top view of the triangular pyramid array in the embodiment.

[0019] The components are as follows: 1-Laser gain medium; 2-First beam splitter module; 201-First half-wave plate; 202-First polarization beam splitter; 3-First frequency selection module; 4-Second beam splitter module; 401-Second half-wave plate; 402-Second polarization beam splitter; 5-Piezoelectric ceramic; 6-First pyramidal array; 7-Second frequency selection module; 8-Third beam splitter module; 801-Third half-wave plate; 802-Third polarization beam splitter; 9-First pyramidal array; 10-Frequency shifter; 11-First semi-reflective lens; 12-Quantum reference and servo locking module; 13-Second semi-reflective lens; 14-Total reflection mirror; 15-Beam combining module; 1501-Fourth half-wave plate; 1502-Fifth half-wave plate; 1503-Fourth polarization beam splitter; 16-Detector; 17-Data processing module; I-Reference arm; II-Measurement arm; III-Frequency locking module; IⅤ-Detection module. Detailed Implementation

[0020] To make the objectives, contents, and advantages of the present invention clearer, the specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples.

[0021] like Figure 1As shown, the integrated Michelson optical frequency standard and displacement measurement system with pyramidal array feedback includes: a Michelson optical frequency standard system (hereinafter referred to as the optical frequency standard system) and a Michelson displacement measurement system (hereinafter referred to as the displacement measurement system). The optical frequency standard system shares a reference arm I of the displacement measurement system, including a laser gain medium 1, a first beam splitting module 2, a first frequency selection module 3, a second beam splitting module 4, a piezoelectric ceramic 5, and a first pyramidal array 6. In addition to the reference arm I, the optical frequency standard system also includes a frequency locking module III, including a frequency shifter 10, a first semi-reflective mirror 11, and a quantum reference and servo locking module 12. In addition to the reference arm I, the displacement measurement system also includes a measurement arm II and a detection module IV. The measurement arm II shares a laser gain medium 1 with the reference arm I and is separated by the first beam splitting module 2. The measurement arm II also includes a second frequency selection module 7, a third beam splitting module 8, and a second pyramidal array 9. The detection module IV includes a second semi-reflective mirror 13, a total reflection mirror 14, a beam combining module 15, a detector 16, and a data processing module 17.

[0022] The laser gain medium 1 outputs a broadband fluorescence signal, providing gain for the optical frequency standard system and the displacement measurement system.

[0023] The first beam splitting module 2 includes a first half-wave plate 201 and a first polarization beam splitter 202. The first polarization plate 201 is used to change the polarization direction of the beam, and the first polarization beam splitter 202 can reflect and transmit the beam according to the polarization direction of the incident light. The two work together to split the incident light. For the light incident from the laser gain medium 1, it is split into two beams by the first beam splitting module 2: the reflected light and the incident light. The reflected light enters the reference arm I, and the transmitted light enters the measurement arm II.

[0024] The first frequency selection module 3 is an optical frequency band filter that only allows light of a specific frequency to pass through the frequency selection module and filters out light of other frequencies, thereby enabling the selection and control of the laser frequency within the reference arm I. The first frequency selection module 3 can use macroscopic components such as interference filters, gratings, Fabry-Polo resonators, etc., or microscopic components such as Faraday anomalous dispersion atomic filters, Focke-Tropsch atomic filters, etc.

[0025] The second beam splitting module 4 includes a second half-wave plate 401 and a second polarizing beam splitter 402. The second polarizing plate 401 is used to change the polarization direction of the beam, and the second polarizing beam splitter 402 can reflect and transmit the beam according to the polarization direction of the incident light. The two work together to split the incident light; one path of transmission reaches the first pyramidal array 6, and one path of reflection reaches the frequency locking module III.

[0026] The first pyramidal array 6 is an array structure composed of multiple pyramidal structures arranged in a certain pattern. It can reflect incident light beams from any direction back to the laser gain medium 1 in their original direction, realizing the oscillation of the light beam between the laser gain medium 1 and the first pyramidal array 6, thus forming a laser beam. .

[0027] The piezoelectric ceramic 5 and the first pyramidal array 6 are bonded together with adhesive. By changing the driving voltage of the piezoelectric ceramic 5, the stroke of the piezoelectric ceramic 5 can be changed, which drives the first pyramidal array 6 to move, thereby changing the distance between the first pyramidal array 6 and the laser gain medium 1, and realizing the frequency tuning of the laser.

[0028] The frequency locking module III includes a frequency shifter 10, a first semi-reflective lens 11, and a quantum reference and servo locking module 12. The frequency shifter 10 can use frequency-shiftable elements such as electro-optic modulators and acousto-optic modulators to control the laser frequency through electro-optic modulation or acousto-optic modulation effects. The first semi-reflective lens 11 divides the incident beam into two paths: transmitted light and reflected light. The reflected light enters the quantum reference and servo locking module 12, and the transmitted light enters the detection module III.

[0029] The quantum reference and servo locking module 12 contains stable frequency references such as atomic and molecular spectral lines. By comparing the difference between the incident laser frequency and the frequency reference, it generates an error signal and feeds it back to the controller of the frequency shifter 10, thereby locking the laser frequency to the frequency corresponding to the reference spectral line. Typical quantum reference and servo locking modules 12 include saturated absorption spectrum frequency stabilization, modulation transfer spectrum frequency stabilization, and two-photon spectrum frequency stabilization.

[0030] The second frequency selection module 7 is used to select the laser frequency of the measuring arm II. Its structure is similar to that of the first frequency selection module 3. Both are filters for optical frequency bands, allowing only specific frequencies of light to pass through the frequency selection module and filtering out other frequencies of light.

[0031] The third beam splitting module 8 includes a third half-wave plate 801 and a third polarizing beam splitter 802. The third polarizing plate 801 is used to change the polarization direction of the beam, and the third polarizing beam splitter 802 can reflect and transmit the beam according to the polarization direction of the incident light. The two work together to split the incident light; one path of transmission reaches the second pyramidal array 9, and one path of reflection enters the detection module IV.

[0032] The second pyramidal array 9 has a structure similar to the first pyramidal array 6. It is fixed on the target and moves synchronously with the target. It can reflect the incident beam back to the laser gain medium 1 in the original direction, realizing the oscillation of the beam between the laser gain medium 1 and the second pyramidal array 9, thus forming a laser beam. .

[0033] The detection module IV includes a second half-reflecting lens 13, a total reflection mirror 14, a beam combiner module 15, a detector 16, and a data processing module 17. The second half-reflecting lens 13 can split the light beam transmitted from the first half-reflecting lens 11 into two paths: a reflected path and a transmitted path. The transmitted light is the output of the optical frequency standard system and is used as a time and frequency reference. The reflected light enters the beam combiner module 15.

[0034] The total reflection mirror 14 can reflect the laser reflected by the third polarization beam splitter 8 into the beam combining module 15.

[0035] The beam combining module 15 includes a fourth half-wave plate 1501, a fifth half-wave plate 1502, and a fourth polarization beam splitter 1503. The fourth half-wave plate 1501 is used to adjust the polarization direction of the light reflected by the total reflection mirror 14 so that it is completely transmitted through the fourth polarization beam splitter 1503. The fifth half-wave plate 1502 is used to adjust the polarization direction of the light reflected by the second half-reflecting lens 13 so that it is completely reflected through the fourth polarization beam splitter 1503, thereby combining the laser beams passed through the fourth half-wave plate 1501 and the fifth half-wave plate 1502. The combined laser beam enters the detector 16.

[0036] Detector 16 is capable of receiving lasers output from the reference arm system. With the laser inside the measuring arm And can read the frequency difference Δυ= between the two. - .

[0037] The data processing module 17 is connected to the detector 16 and is capable of acquiring laser data before displacement measurement. With laser Frequency difference Δυ and displacement measurement after laser With laser Frequency difference Δυ And obtain the magnitude of the displacement.

[0038] like Figure 2 As shown, when the target under test drives the second pyramidal array 9 along the laser... When moving in a direction parallel to the propagation direction, assuming the magnitude of the displacement is dl, this displacement will cause a change in the laser frequency within measuring arm II. Let the initial laser frequency within measuring arm II be... The laser frequency inside the measuring arm after displacement measurement is Because reference arm I is a highly stable optical frequency standard system, the output frequency remains constant. Therefore, the change in frequency difference obtained by detector 16 is essentially the change in laser frequency within measurement arm II. Based on the relationship between laser frequency and displacement Δν / ν=dL / L, we can derive dl=( )L / , where L is the initial cavity length of the measuring arm, which is obtained in the data processing module 17.

[0039] In the above structure, the optical frequency standard signal is transmitted and output by the second half-reflective lens 13, and the displacement measurement signal is calculated by the data processing module 17. Therefore, the present invention can simultaneously complete the measurement of time frequency and displacement in an integrated structure.

[0040] like Figure 3 As shown, when the second pyramidal array 9 moves slightly along the non-displacement measurement direction, the movement will not change the optical path of the measuring arm II because the pyramidal structures on its surface are highly similar, and therefore will not affect the laser mode within the measuring arm II.

[0041] like Figure 4 As shown, when the pitch angle of the second pyramid array 9 changes, since the pyramid array can accurately reflect the incident beam in any direction along the original direction, the change in pitch angle will not cause a change in the optical path of the measuring arm II, and therefore will not affect the laser mode in the measuring arm II.

[0042] like Figure 5 As shown, the first pyramid array 6 and the second pyramid array 9 can be selected as triangular pyramid structures. A triangular pyramid array consists of multiple triangular pyramid units located in the same plane. The regular triangular pyramid array is one type of triangular pyramid array, with three mutually perpendicular isosceles right triangles on its three sides and an equilateral triangle on its base. Regardless of the shape, all pyramid arrays have a base plane and a pyramidal surface, and their basic functions are similar.

[0043] The above description is merely a preferred embodiment of the present invention. It should be noted that other types of integrated Michelson optical frequency standard and displacement measurement systems with pyramidal array feedback should be considered within the scope of protection of the present invention. To further improve the displacement measurement resolution and accuracy of the system, technical solutions such as placing the aforementioned integrated Michelson optical frequency standard and displacement measurement system with pyramidal array feedback on a vibration isolation platform or in a vacuum environment should also be considered within the scope of protection of the present invention. For those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. An integrated Michelson optical frequency standard and displacement measurement system with pyramidal array feedback, characterized in that, The system includes an optical frequency standard system and a displacement measurement system, which share the same reference arm. The optical frequency standard system further includes a frequency locking module, a frequency shifter, a first semi-reflective lens, and a quantum reference and servo locking module. The displacement measurement system further includes a measuring arm and a detection module. The target to be measured is attached to the second pyramidal array. The measuring arm and the reference arm share the same laser gain medium and the first beam splitting module; the reference arm further includes a first frequency selection module, a second beam splitting module, piezoelectric ceramics, and a first pyramidal array; the measuring arm further includes a second frequency selection module, a third beam splitting module, and a second pyramidal array; The laser gain medium is used to output a broadband fluorescence signal to provide gain for the optical frequency standard system and the displacement measurement system. The first beam-splitting module is used to split the light output from the laser gain medium into two beams. One beam passes sequentially through the first frequency selection module, the second beam-splitting module, and the first pyramidal array of the reference arm before returning to the laser gain medium, thereby achieving oscillation of the beam between the laser gain medium and the first pyramidal array, forming a frequency of [frequency value missing]. The reference laser; another beam passes sequentially through the second frequency selection module, the third beam splitting module, and the second pyramidal array of the measuring arm before returning to the laser gain medium, realizing the oscillation of the beam between the laser gain medium and the second pyramidal array, forming a frequency of... The measuring laser; The second beam splitting module is used to split the incident light into two beams, one of which is incident on the first pyramidal array and the other is input to the frequency locking module. The third beam splitting module is used to split the incident light into two beams, one of which is incident on the second pyramidal array and the other is input to the detection module; The first frequency selection module is used to select the laser frequency within the reference arm; the second frequency selection module is used to select the laser frequency within the measurement arm. The piezoelectric ceramic is disposed on the first pyramidal array and is used to adjust the frequency of the reference laser in the reference arm; The frequency locking module includes a frequency shifter, a first semi-reflective lens, and a quantum reference and servo locking module. The frequency shifter is used to adjust the laser frequency. The first semi-reflective lens is used to split the incident beam into two paths, one of which is input to the quantum reference and servo locking module, and the other is input to the detection module. The quantum reference and servo locking module is used to generate an error signal by comparing the difference between the incident laser frequency and a set frequency reference, and feed it back to the controller of the frequency shifter to lock the laser frequency to the frequency reference. The detection module includes a second half-reflecting lens, a total reflection mirror, a beam combiner module, a detector, and a data processing module. The second half-reflecting lens is used to split the light beam sent from the first half-reflecting lens into two paths, one path serving as the output signal of the optical frequency standard system for time and frequency measurement, and the other path being input to the beam combiner module. The total reflection mirror reflects the light beam sent from the third split beam into the beam combiner module. The beam combining module includes a fourth half-wave plate, a fifth half-wave plate, and a fourth polarization beam splitter; the fourth half-wave plate is used to adjust the polarization direction of the light reflected by the total reflection mirror, and the fifth half-wave plate is used to adjust the polarization direction of the light reflected by the second half-reflection lens; the fourth polarization beam splitter combines the laser beams that have passed through the fourth half-wave plate and the fifth half-wave plate, and the combined laser beam enters the detector. The detector is used to receive the reference laser output from the reference arm and the measurement laser inside the measurement arm, and to calculate the frequency difference between the two. And input it into the data processing module; The data processing module is used to process data based on frequency differences. The displacement of the target under test is calculated from the change in the value of the change.

2. The integrated Michelson optical frequency standard and displacement measurement system according to claim 1, characterized in that, The data processing module uses the formula dl=( )L / The displacement dl of the target to be measured is calculated; where L is the initial cavity length of the measuring arm. The frequency of the laser measured inside the measuring arm is determined before the target moves. The frequency of the laser measured inside the measuring arm after the target under test moves.

3. The integrated Michelson optical frequency standard and displacement measurement system according to claim 1, characterized in that, The quantum reference and servo-locking module uses quantum spectral lines as the frequency reference.

4. The integrated Michelson optical frequency standard and displacement measurement system according to claim 1, 2, or 3, characterized in that, The first beam splitting module includes a first half-wave plate and a first polarizing beam splitter. The first polarizing plate is used to change the polarization direction of the beam, and the first polarizing beam splitter is used to reflect and transmit the beam according to the polarization direction of the incident light, wherein the reflected light enters the reference arm and the transmitted light enters the measurement arm.

5. The integrated Michelson optical frequency standard and displacement measurement system according to claim 1, 2, or 3, characterized in that, The second beam splitting module includes a second half-wave plate and a second polarizing beam splitter. The second polarizing plate is used to change the polarization direction of the beam, and the second polarizing beam splitter is used to reflect and transmit the beam according to the polarization direction of the incident light. The transmitted beam is incident on the first pyramidal array, and the reflected beam is input to the frequency-locking module.

6. The integrated Michelson optical frequency standard and displacement measurement system according to claim 1, 2, or 3, characterized in that, The third beam splitting module includes a third half-wave plate and a third polarizing beam splitter. The third polarizing plate is used to change the polarization direction of the beam, and the third polarizing beam splitter is used to reflect and transmit the beam according to the polarization direction of the incident light. The transmitted beam is incident on the second pyramidal array, and the reflected beam is input to the detection module.

7. The integrated Michelson optical frequency standard and displacement measurement system according to claim 1, 2, or 3, characterized in that, The first frequency selection module is an interference filter, a grating, a Fabry-Polo resonator, or a Faraday anomalous dispersion atomic filter or a Focke atomic filter.

8. The integrated Michelson optical frequency standard and displacement measurement system according to claim 1, 2, or 3, characterized in that, Both the first pyramid array and the second pyramid array are triangular pyramids, and the pyramidal surfaces of the triangular pyramid array are composed of triangular pyramid arrays.

9. The integrated Michelson optical frequency standard and displacement measurement system according to claim 8, characterized in that, The pyramidal facets of the triangular pyramid array are composed of a regular triangular pyramid array, with each regular triangular pyramid having three mutually perpendicular isosceles right triangles on its three sides and an equilateral triangle on its base.

10. The integrated Michelson optical frequency standard and displacement measurement system according to claim 9, characterized in that, The outer surface of the triangular pyramidal array is coated with a high-reflectivity film, and the reflection wavelength of the high-reflectivity film is the same as the center wavelength of the laser output by the laser gain medium.

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