Device and method for improving stability of vacuum compression state light field generator

Abstract

The invention discloses a device and method for improving the stability of a vacuum compression state light field generator, and relates to the technical field of quantum optics. The cavity length of the vacuum compression state light field generator is locked in a closed loop mode through reflecting pump light; enabling the seed light and a vacuum compression state light field generator to resonate, matching the power and light spot modes of the seed light and the local light, and then performing coupling interference; adjusting the phase to constructive interference, and collecting an interference signal and a frequency spectrum thereof by using a Fourier real-time analysis oscilloscope so as to identify extra noise; and finally, noise is suppressed by combining air floating platform pressure optimization and negative feedback servo control system parameter adjustment, so that the stability of the vacuum compression state light field generator is improved. The stability of the vacuum compression state light field generator can be effectively improved, and the vacuum compression state light field generator can be widely popularized and applied to an experiment system for preparing a vacuum compression state light field.

Description

[0001] Method The present application relates to the technical field of quantum optics, and particularly to a device and method for improving the stability of a vacuum squeezed light field generator.

[0002] Background method The vacuum squeezed light field is an important non-classical light field resource, and plays a core role in the fields of quantum key distribution, gravitational wave detection, quantum precision measurement, etc. The vacuum squeezed light field generator, as a core device for preparing a squeezed light field, its working stability directly determines the key performance parameters of the output light field, such as the squeezing degree and noise level.

[0003] However, the vacuum squeezed light field generator is easily affected by external environmental disturbances, such as temperature fluctuations, mechanical vibrations, and internal device drifts, such as cavity mirror and crystal thermal deformation, and piezoelectric ceramic aging, resulting in a slight change in the cavity length of the optical resonant cavity. The instability of the cavity length will destroy the resonance condition, causing the squeezing degree of the output light field to decay, additional noise to be introduced, and other problems.

[0004] The prior art mostly adopts a single cavity length locking scheme, for example, by detecting the reflection signal of the pump light, and adjusting the cavity length by using a negative feedback servo control system. However, such a scheme has defects. The existing scheme lacks real-time monitoring and feedback of the stability of the vacuum squeezed light field generator, and it is difficult to accurately locate the root cause of the stability problem, resulting in low parameter adjustment efficiency and limited stability improvement effect in the locking process.

[0005] Therefore, the present application provides a device and method for improving the stability of a vacuum squeezed light field generator to solve the above problems. SUMMARY

[0006] The purpose of the present application is to provide a device and method for improving the stability of a vacuum squeezed light field generator, which accurately locates the stability problem through noise analysis of the interference signal, and realizes high-precision stability control of the vacuum squeezed light field generator by optimizing the parameters of the servo control system.

[0007] To achieve the above purpose, the present application provides a method for improving the stability of a vacuum squeezed light field generator, comprising the following steps: S1: obtaining an optical signal, converting the optical signal into an electrical signal, and inputting the electrical signal into a negative feedback servo control system; S2: locking the cavity length of the vacuum squeezed light field generator according to the electrical signal input in S1; S3: inputting seed light in the vacuum squeezed light field generator in step S2, the seed light power transmitted by the vacuum squeezed light field generator being the same as the local light power, and the local light and the transmitted seed light being coupled to interfere; S4: adjusting the driving voltage, controlling the relative phase between the local light and the transmitted seed light in S3, so that the local light and the transmitted seed light constructively interfere; S5: detecting the constructive interference light signal obtained in step S4, outputting a direct current signal and a corresponding real-time spectrum, analyzing the real-time spectrum, and identifying the technical noise carried therein; S6: optimizing the pressure parameters of the air floating platform and the parameters of the negative feedback servo control system to minimize the noise amplitude in the spectrum characteristics.

[0008] Preferably, in S1, the reflected pump light of the vacuum squeezed light field generator is used as an optical feedback signal, the optical feedback signal is converted into an error electric signal by a third photodetector, and the error electric signal is input into the negative feedback servo control system; The negative feedback servo control system is a Pound-Drever-Hall frequency stabilization system, which includes a high-frequency signal generator, a mixer, a low-pass filter, a low-noise power amplifier, a proportional-integral controller, and a high-voltage amplifier.

[0009] Preferably, in S2, the negative feedback servo control system performs closed-loop negative feedback control on the cavity length of the vacuum squeezed light field generator according to the error electric signal input in S1, the negative feedback servo control system precisely adjusts the cavity length by driving the piezoelectric ceramic in the vacuum squeezed light field generator, and locks the cavity length of the vacuum squeezed light field generator.

[0010] Preferably, S3 specifically includes the following steps: S31: injecting the seed light into the vacuum squeezed light field generator so that the seed light resonates with the vacuum squeezed light field generator; S32: adjusting the power of the seed light transmitted by the vacuum squeezed light field generator so that the power of the transmitted seed light is the same as that of the local light; S33: adjusting the beam parameters of the local light by the adjustable beam expander so that the spot size and mode of the transmitted seed light and the local light are matched; S34: coupling the local light and the transmitted seed light which are matched in power and mode to interfere by the fourth beam splitter.

[0011] Preferably, in S4, the driving voltage loaded on the piezoelectric ceramic of the third mirror is adjusted to accurately control the relative phase between the local light and the transmitted seed light in S3, and the relative phase difference is adjusted to an even multiple of π so that the two lights constructively interfere.

[0012] Preferably, S5 specifically includes the following steps: S51: detecting the constructive interference light signal obtained in S4 by the second photodetector, converting it into an electric signal, and then monitoring it by a Fourier real-time analysis oscilloscope; S52: Fourier real-time analysis oscilloscope synchronously collects and displays the direct current signal and the corresponding real-time spectrum output from S51; S53: analyze the real-time spectrum characteristics, and identify the additional technical noise carried in the optical signal.

[0013] Preferably, S6 specifically represents the optimization of the air floating pressure of the experimental platform, the optimization of the main parameters in the negative feedback servo control system, and the minimization of the noise amplitude in the spectrum characteristics. The main parameters include the signal gain, PI bandwidth and low frequency gain of the proportional integral controller, and the gain and bias of the high voltage amplifier.

[0014] A device for improving the stability of a vacuum squeezed light field generator is applied to a method for improving the stability of a vacuum squeezed light field generator, which comprises a solid-state laser and a frequency doubler arranged on the left and right sides of a first beam splitter, a second beam splitter arranged on the other side of the frequency doubler, a third beam splitter arranged between the second beam splitter and the vacuum squeezed light field generator, the second beam splitter and the third beam splitter being symmetrically arranged, a third photodetector arranged above the third beam splitter, a negative feedback servo control system arranged above the third photodetector and the vacuum squeezed light field generator, a fourth beam splitter arranged between the vacuum squeezed light field generator and a second photodetector, a first photodetector and a third mirror arranged on the upper and lower sides of the fourth beam splitter, and a Fourier real-time analysis oscilloscope arranged on the other side of the second photodetector. The solid-state laser, the first beam splitter, the frequency doubler, the second beam splitter, the third beam splitter, the vacuum squeezed light field generator, the fourth beam splitter and the second photodetector are arranged on the same horizontal line.

[0015] Preferably, the third mirror is provided with a second mirror, the second mirror and the first beam splitter are provided with a fifth beam splitter, the fifth beam splitter is provided with a first mirror on one side, and the first mirror and the second beam splitter are arranged on the same vertical line.

[0016] Preferably, the third mirror is provided with a piezoelectric ceramic.

[0017] Therefore, the device and method for improving the stability of the vacuum squeezed light field generator have the following beneficial effects: (1) The present application solves the problem of only locking and not monitoring by analyzing the spectrum of the laser interference signal and capturing the low-frequency cavity length jitter in the vacuum squeezed light field generator in real time, and provides accurate basis for adjusting the key parameters in the negative feedback servo control system.

[0018] (2) The light path and circuit design of the application is suitable for most vacuum squeezed light field generators, and is easy to popularize in experimental systems for preparing such vacuum squeezed light fields.

[0019] (3) The application optimizes the pressure parameters of the experimental air floating platform, and minimizes the noise amplitude in the frequency spectrum characteristics by adjusting the signal gain, PI bandwidth, low frequency gain of the proportional integral controller in the negative feedback servo control system, and the gain and bias of the high voltage amplifier, thereby improving the stability of the vacuum squeezed light field generator.

[0020] The method scheme of the application will be further described in detail below with reference to the drawings and examples. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 is a device diagram for improving the stability of the vacuum squeezed light field generator of the application; Figure 2 is a flowchart for improving the stability of the vacuum squeezed light field generator of the application; Figure 3 is a frequency spectrum curve diagram of the laser interference signal collected in the implementation of the application; Figure 4 is a frequency spectrum curve diagram collected after optimizing the key parameters in the negative feedback servo control system in the implementation example of the application. BRIEF DESCRIPTION OF DRAWINGS

[0022] 1, all-solid-state laser; 2, first beam splitter; 3, frequency doubler; 4, second beam splitter; 5, third beam splitter; 6, vacuum squeezed light field generator; 7, fourth beam splitter; 8, first photodetector; 9, second photodetector; 10, Fourier real-time analysis oscilloscope; 11, third photodetector; 12, negative feedback servo control system; 13, fifth beam splitter; 14, first mirror; 15, second mirror; 16, third mirror. DETAILED DESCRIPTION

[0023] The method scheme of the application will be further described in detail below with reference to the drawings and examples.

[0024] Unless otherwise defined, the method terms or scientific terms used in the application shall have the usual meanings understood by those skilled in the art to which the application belongs.

[0025] The "including" or "comprising" and similar words used in the present invention mean that the elements before the word encompass the elements listed after the word, and do not exclude the possibility of also encompassing other elements. The orientation or positional relationship indicated by the terms "in", "out", "upper", "lower" and the like is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present invention, and when the absolute position of the described object changes, the relative positional relationship may also change accordingly. In the present invention, unless otherwise explicitly specified and limited, the term "attached" and other terms should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal connection of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above-mentioned terms in the present invention can be understood according to the specific circumstances.

[0026] Embodiment As Figure 1 shown, an improved vacuum compressed state light field generator stability device is applied to an improved vacuum compressed state light field generator stability method: a full solid state laser 1 and a frequency doubler 3 are arranged on the left and right sides of a first beam splitter 2, the other side of the frequency doubler 3 is provided with a second beam splitter 4, a third beam splitter 5 is arranged between the second beam splitter 4 and a vacuum compressed state light field generator 6, the second beam splitter 4 and the third beam splitter 5 are symmetrically arranged, a third photodetector 11 is arranged above the third beam splitter 5, a negative feedback servo control system 12 is arranged above the vacuum compressed state light field generator 6 and the third photodetector 11, a fourth beam splitter 7 is arranged between the vacuum compressed state light field generator 6 and a second photodetector 9, a first photodetector 8 and a third mirror 16 are arranged on the upper and lower sides of the fourth beam splitter 7 respectively, and a Fourier real-time analysis oscilloscope 10 is arranged on the other side of the second photodetector 9. The full solid state laser 1, the first beam splitter 2, the frequency doubler 3, the second beam splitter 4, the third beam splitter 5, the vacuum compressed state light field generator 6, the fourth beam splitter 7 and the second photodetector 9 are arranged on the same horizontal line.

[0027] The third mirror 16 is provided with a piezoelectric ceramic, one side of the third mirror 16 is provided with a second mirror 15, a fifth beam splitter 13 is arranged between the second mirror 15 and the first beam splitter 2, a first mirror 14 is arranged on one side of the fifth beam splitter 13, and the first mirror 14 and the second beam splitter 4 are arranged on the same vertical line.

[0028] The laser output by the all-solid-state laser 1 is injected into the frequency doubler 3 after being transmitted by the first beam splitter 2, the frequency-doubled light output by the frequency doubler 3 is sequentially injected into the vacuum squeezed light field generator 6 through the second beam splitter 4 and the third beam splitter 5, and the injection light is the pump light of the vacuum squeezed light field generator 6; the reflected light of the first beam splitter 2 is injected into the vacuum squeezed light field generator 6 through the fifth beam splitter 13, the first mirror 14, the second beam splitter 4 and the third beam splitter 5, and the injection light is the seed light of the vacuum squeezed light field generator 6; the transmitted light of the fifth beam splitter 13 sequentially passes through the second mirror 15 and the third mirror 16 to reach the fourth beam splitter 7, and the light beam is the local light.

[0029] The local light and the transmitted seed light of the vacuum squeezed light field generator 6 are coupled through the fourth beam splitter 7, the reflected signal of the fourth beam splitter 7 enters the first photodetector 8, the transmitted signal of the fourth beam splitter 7 enters the second photodetector 9, and the output signal of the second photodetector 9 is connected to the Fourier real-time analysis oscilloscope 10. The reflected pump light of the vacuum squeezed light field generator 6 enters the third photodetector 11 after being reflected by the third beam splitter 5, the output signal of the third photodetector 11 enters the negative feedback servo control system 12, and the output of the negative feedback servo control system 12 is connected to the vacuum squeezed light field generator 6.

[0030] The output power of the all-solid-state laser 1 is 6W, and the central wavelength is 1064nm; the output power of the frequency doubler 3 is 1.2W, and the central wavelength is 532nm; the nonlinear crystal is LBO, and the working temperature is 149℃; the vacuum squeezed light field generator 6 is a semi-integral cavity structure, the nonlinear crystal is PPKTP, and the working temperature is 34℃; the fourth beam splitter 7 is a 50 / 50 beam splitter; the first photodetector 8 and the second photodetector 9 are a pair of balanced detectors made in the laboratory; the Fourier real-time analysis oscilloscope 10 is a Puyuan DHO4204 oscilloscope; the negative feedback servo control system 12 is a Pound-Drever-Hall frequency stabilization system, which includes a high-frequency signal generator, a mixer, a low-pass filter, a low-noise power amplifier, a proportional-integral controller and a high-voltage amplifier.

[0031] As shown in Figure 2 A method for improving the stability of a vacuum squeezed light field generator, comprising the following steps: S1: obtaining an optical signal, converting the optical signal into an electrical signal, and inputting the electrical signal into a negative feedback servo control system; in S1, the reflected pump light of the vacuum squeezed light field generator is taken as an optical feedback signal, the optical feedback signal is converted into an error electrical signal by a third photodetector, and the error electrical signal is input into the negative feedback servo control system; The negative feedback servo control system is a Pound-Drever-Hall frequency stabilization system, and comprises a high-frequency signal generator, a mixer, a low-pass filter, a low-noise power amplifier, a proportional-integral controller and a high-voltage amplifier.

[0032] S2: locking the cavity length of the vacuum squeezed light field generator according to the input electrical signal in S1; in S2, the negative feedback servo control system performs closed-loop negative feedback control on the cavity length of the vacuum squeezed light field generator according to the input error electrical signal in S1, the negative feedback servo control system precisely adjusts the cavity length by driving the piezoelectric ceramic in the vacuum squeezed light field generator, the cavity length of the vacuum squeezed light field generator is locked, and the vacuum squeezed light field generator is stably operated. In the cavity length locking process, the modulation frequency is 21 MHz, and the modulation amplitude is 5 V; the signal gain of the proportional-integral controller is 5.6 times, the PI bandwidth is 30 kHz, and the low-frequency gain is 20 dB; the bias of the high-voltage amplifier is 236 V.

[0033] S3: inputting seed light into the vacuum squeezed light field generator in step S2, the power of the transmitted seed light of the vacuum squeezed light field generator being the same as the power of the local light, and the local light being coupled with the transmitted seed light to generate interference; S3 specifically comprises the following steps: S31: injecting seed light into the vacuum squeezed light field generator so that the seed light is resonated with the vacuum squeezed light field generator; S32: adjusting the power of the transmitted seed light of the vacuum squeezed light field generator so that the power of the transmitted seed light is the same as the power of the local light, and in the experiment, the powers of the two beams of light are both 1.5 mW; S33: adjusting the beam parameters of the local light by using an adjustable beam expander so that the spot size and mode of the transmitted seed light are matched with those of the local light, and in the experiment, the mode matching efficiency is about 98.5%; S34: coupling the local light and the transmitted seed light, which have matched powers and modes, to generate interference by using a fourth beam splitter.

[0034] S4: adjusting the driving voltage to control the relative phase between the local light and the transmitted seed light in S3 so that the local light and the transmitted seed light generate constructive interference; in S4, the driving voltage loaded on the piezoelectric ceramic of the third mirror is adjusted to accurately control the relative phase between the local light and the transmitted seed light in S3, the relative phase difference is adjusted to an even multiple of π, and the two beams of light generate constructive interference.

[0035] S5: detecting the constructive interference light signal obtained in step S4 to output a direct current electrical signal and a corresponding real-time spectrum, and analyzing the real-time spectrum to identify the technical noise carried thereby; S5 specifically comprises the following steps: S51: detecting the constructive interference light signal obtained in S4 by using a second photodetector, converting the constructive interference light signal into an electrical signal, and monitoring the electrical signal by using a Fourier real-time analysis oscilloscope. S52: The Fourier real-time analysis oscilloscope synchronously acquires and displays the DC signal output from S51 and the corresponding real-time spectrum; S53: Analyze the real-time spectral characteristics to identify additional technical noise carried in the optical signal; such as Figure 3 As shown, the optical signal carries considerable additional technical noise. For example, sharp noise with amplitudes greater than 800mV is present at the analysis frequencies of 50Hz and 150Hz; noise is also present at other multiples of 50Hz; a noise cluster with an amplitude of approximately 200mV is present near the analysis frequency of 20Hz; and a noise cluster with an amplitude of approximately 150mV is present in the analysis frequency range of 120-140Hz. The sources of this noise are identified as mechanical vibration and noise introduced during the cavity locking process of the vacuum-compressed optical field generator.

[0036] S6: Optimize the air flotation platform pressure parameters and the negative feedback servo control system parameters to minimize the noise amplitude in the spectral characteristics. In S6, the air flotation pressure of the experimental platform is slightly increased from 0.7 MPa to 0.72 MPa; the main parameters in the negative feedback servo control system are optimized, including the signal gain, PI bandwidth, and low-frequency gain of the proportional-integral controller, as well as the gain and bias of the high-voltage amplifier; the signal gain of the proportional-integral controller in the negative feedback servo control system is adjusted by 4.2 times, and the low-frequency error signal gain is adjusted by 30 dB. The spectral curves acquired after parameter optimization are shown below. Figure 4 As shown, the amplitude of sharp noise at the analysis frequencies of 50Hz and 150Hz decreased from about 800mV to about 15mW; the noise clusters at the analysis frequencies of 120-140Hz were completely removed; and the noise amplitudes at other frequencies were reduced.

[0037] Therefore, the present invention employs the above-mentioned device and method for improving the stability of a vacuum compressed light field generator. By combining real-time monitoring of laser interference signals with parameter adjustment of the servo control system, the stability problem of the vacuum compressed light field generator can be accurately located, and its working stability can be significantly improved through parameter optimization.

[0038] Finally, it should be noted that the above embodiments are only used to illustrate the method of the present invention and not to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the method of the present invention, and these modifications or equivalent substitutions should not cause the modified method to deviate from the spirit and scope of the method of the present invention.

Claims

1. A method for improving the stability of a vacuum-compressed optical field generator, characterized in that: Includes the following steps: S1: Acquire optical signals, convert them into electrical signals, and input them into the negative feedback servo control system; S2: Lock the cavity length of the vacuum compressed light field generator according to the electrical signal input in S1; S3: In step S2, seed light is input into the vacuum compressed state light field generator. The power of the seed light transmitted by the vacuum compressed state light field generator is the same as the power of the local light. The local light and the transmitted seed light are coupled and interfere. S4: Adjust the driving voltage to control the relative phase between the local light and the transmitted seed light in S3, so that the local light and the transmitted seed light will undergo constructive interference. S5: Detect the constructive interference optical signal obtained in step S4, output a DC signal and the corresponding real-time spectrum, analyze the real-time spectrum, and identify the technical noise carried. S6: Optimize the pressure parameters of the air flotation platform, optimize the parameters of the negative feedback servo control system, and minimize the noise amplitude in the spectrum characteristics.

2. The method for improving the stability of a vacuum-compressed optical field generator according to claim 1, characterized in that, In S1, the reflected pump light from the vacuum compressed state light field generator is used as an optical feedback signal. The optical feedback signal is converted into an error electrical signal by the third photodetector, and the error electrical signal is input to the negative feedback servo control system. The negative feedback servo control system is a Pound-Drever-Hall frequency stabilization system, which includes a high-frequency signal generator, mixer, low-pass filter, low-noise power amplifier, proportional-integral controller and high-voltage amplifier.

3. The method for improving the stability of a vacuum-compressed optical field generator according to claim 1, characterized in that, The negative feedback servo control system in S2 performs closed-loop negative feedback control on the cavity length of the vacuum compressed light field generator based on the error electrical signal input in S1. The negative feedback servo control system achieves precise adjustment of the cavity length by driving the piezoelectric ceramic in the vacuum compressed light field generator, thereby locking the cavity length of the vacuum compressed light field generator.

4. The method for improving the stability of a vacuum-compressed optical field generator according to claim 1, characterized in that, S3 specifically includes the following steps: S31: Inject the seed light into the vacuum compressed state light field generator so that the seed light resonates with the vacuum compressed state light field generator; S32: Adjust the seed light power transmitted from the vacuum compressed light field generator so that the transmitted seed light power is the same as the local light power; S33: Adjust the beam parameters of the local light by using an adjustable beam expander to match the spot size and pattern of the transmitted seed light with that of the local light; S34: The local light and the transmitted seed light, which are matched in power and mode, are coupled together by the fourth beam splitter to cause interference.

5. The method for improving the stability of a vacuum-compressed optical field generator according to claim 1, characterized in that, In S4, the driving voltage applied to the piezoelectric ceramic of the third reflecting mirror is adjusted to precisely control the relative phase between the local light and the transmitted seed light in S3, adjusting the relative phase difference to an even multiple of π, so that the two beams of light undergo constructive interference.

6. The method for improving the stability of a vacuum-compressed optical field generator according to claim 1, characterized in that, S5 specifically includes the following steps: S51: The second photodetector is used to detect the constructive interference light signal obtained in S4. After the interference light signal is converted into an electrical signal, it is monitored by a Fourier real-time analysis oscilloscope. S52: The Fourier real-time analysis oscilloscope synchronously acquires and displays the DC signal output from S51 and the corresponding real-time spectrum; S53: Analyze the real-time spectral characteristics to identify additional technical noise carried in the optical signal.

7. The method for improving the stability of a vacuum-compressed optical field generator according to claim 1, characterized in that, Specifically, S6 means: optimizing the air flotation pressure of the experimental platform, optimizing the main parameters in the negative feedback servo control system, and minimizing the noise amplitude in the spectrum characteristics; Key parameters include the signal gain, PI bandwidth, low-frequency gain of the proportional-integral controller, and the gain and bias of the high-voltage amplifier.

8. A device for improving the stability of a vacuum compressed state light field generator is applied to a method for improving the stability of a vacuum compressed state light field generator as described in any one of claims 1-7, characterized in that: The system includes all-solid-state lasers and frequency doublers positioned on either side of a first beam splitter. A second beam splitter is positioned on the other side of the frequency doubler. A third beam splitter is positioned between the second beam splitter and a vacuum-compressed light field generator. The second and third beam splitters are symmetrically positioned. A third photodetector is positioned above the third beam splitter. A negative feedback servo control system is positioned above the third photodetector and the vacuum-compressed light field generator. A fourth beam splitter is positioned between the vacuum-compressed light field generator and the second photodetector. A first photodetector and a third reflector are positioned on the upper and lower sides of the fourth beam splitter, respectively. A Fourier real-time analysis oscilloscope is positioned on the other side of the second photodetector. The all-solid-state laser, the first beam splitter, the frequency doubler, the second beam splitter, the third beam splitter, the vacuum compressed state light field generator, the fourth beam splitter, and the second photodetector are all positioned on the same horizontal line.

9. The device for improving the stability of a vacuum compressed optical field generator according to claim 8, characterized in that, A second reflector is provided on one side of the third reflector, and a fifth beam splitter is provided between the second reflector and the first beam splitter. A first reflector is provided on one side of the fifth beam splitter, and the first reflector and the second beam splitter are arranged on the same vertical line.

10. The device for improving the stability of a vacuum compressed optical field generator according to claim 8, characterized in that, The third reflecting mirror is equipped with piezoelectric ceramics.

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