Photoacoustic spectrum detection method and system with laser wavelength deviation detection function

Abstract

The invention relates to a photoacoustic spectrum detection method and system with a laser wavelength deviation detection function. The method comprises the following steps: calibrating a Fabry-Perot etalon; controlling the cavity temperature of the calibrated Fabry-Perot etalon through a double-loop temperature control and PID (Proportion Integration Differentiation) control algorithm until the cavity temperature change reaches a threshold value within a preset time; the Fabry-Perot etalon subjected to temperature control is coupled with a photoacoustic signal source; detecting and collecting a photoacoustic signal through a photoelectric detector, and denoising the photoacoustic signal through a second harmonic wavelength modulation method; and reconstructing the denoised photoacoustic signal based on compressed sensing and a two-step iterative shrinkage method. Through the combination of temperature control, wavelength tuning and compressed sensing methods, the noise of the photoacoustic signal is reduced, and the accuracy and sensitivity of photoacoustic signal detection are improved.

Description

Technical Field

[0001] The invention belongs to the technical field of spectrum detection, and in particular relates to a detection method and system of photoacoustic spectrum with laser wavelength deviation detection. Background Art

[0002] In photoacoustic spectroscopy, accurate detection of laser wavelength and high-sensitivity detection of photoacoustic signals are the key to achieving high-precision measurement. However, when faced with laser wavelength deviation and ambient temperature changes, traditional photoacoustic spectroscopy detection technology often suffers from measurement errors and signal noise, which affects the accuracy and stability of detection. Summary of the invention

[0003] In order to improve the accuracy and stability of photoacoustic spectroscopy detection, a first aspect of the present invention provides a photoacoustic spectroscopy detection method with laser wavelength deviation detection, comprising: calibrating a Fabry-Perot etalon based on a standard light source with multiple wavelengths of a target laser; controlling the cavity temperature of the calibrated Fabry-Perot etalon through a dual-loop temperature control and PID control algorithm until the cavity temperature change reaches a threshold within a preset time; coupling the temperature-controlled Fabry-Perot etalon with a wavelength-tunable laser source, and then irradiating a photoacoustic cell with the laser source; detecting and collecting photoacoustic signals through a photodetector, and denoising the photoacoustic signals through a second harmonic wavelength modulation method; and reconstructing the denoised photoacoustic signals based on compressed sensing and a two-step iterative shrinkage method.

[0004] In some embodiments of the present invention, the cavity temperature of the calibrated Fabry-Perot etalon is controlled by dual-loop temperature control and PID control algorithm until the cavity temperature changes to a threshold value within a preset time, including: installing a thermoelectric cooler and a temperature sensor at multiple locations in the cavity of the Fabry-Perot etalon to detect the cavity temperature in real time; controlling the thermal measurement temperature of the thermoelectric cooler by an outer-loop PID controller, and controlling the cold measurement temperature of the thermoelectric cooler by an inner-loop PID controller to stabilize after the thermal measurement temperature stabilizes; setting the cavity temperature of the Fabry-Perot etalon, and controlling the cavity temperature of the calibrated Fabry-Perot etalon by the stabilized outer-loop PID controller and the inner-loop PID controller until the cavity temperature changes to a threshold value within a preset time.

[0005] Furthermore, the control method of the outer loop PID controller is expressed as: , u(t) Indicates the controller output regulation voltage; e(t) represents the temperature error,K p 、K i 、K d They represent proportional gain, integral gain and differential gain respectively.

[0006] In some embodiments of the present invention, the denoising of the photoacoustic signal by the second harmonic wavelength modulation method includes: synchronously detecting the phase difference between the photoacoustic signal and the reference signal by a phase-locked amplifier, and extracting the second harmonic component of the photoacoustic signal; calculating the intensity and distribution of the photoacoustic signal based on the amplitude and phase changes of the second harmonic component; and denoising the photoacoustic signal based on the intensity and distribution of the photoacoustic signal.

[0007] In some embodiments of the present invention, the reconstruction of the denoised photoacoustic signal based on compressed sensing and a two-step iterative shrinkage method includes: reconstructing the initial pressure distribution of the photoacoustic signal from sparse measurement data through a compressed sensing method; and updating and iterating the initial pressure distribution through a two-step iterative shrinkage method until the soft threshold difference between adjacent iterative signals is lower than a preset value.

[0008] Furthermore, the soft threshold is calculated by the following steps: , in T Represents soft threshold ,l represents the threshold parameter, x represents the photoacoustic signal, and sign(x) represents the sign function.

[0009] In a second aspect of the present invention, a detection system for photoacoustic spectroscopy with laser wavelength deviation detection is provided, comprising: a calibration module, used to calibrate a Fabry-Perot etalon based on a standard light source of multiple wavelengths of a target laser; a control module, used to control the cavity temperature of the calibrated Fabry-Perot etalon through a dual-loop temperature control and a PID control algorithm until the cavity temperature change reaches a threshold value within a preset time; a coupling module, used to couple the temperature-controlled Fabry-Perot etalon with a wavelength-tunable laser source, and then use the laser source to irradiate a photoacoustic cell; a denoising module, used to detect and collect photoacoustic signals through a photodetector, and denoise the photoacoustic signals through a second harmonic wavelength modulation method; and a reconstruction module, used to reconstruct the denoised photoacoustic signals based on compressed sensing and a two-step iterative shrinkage method.

[0010] In a third aspect of the present invention, an electronic device is provided, comprising: one or more processors; a storage device for storing one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors implement the photoacoustic spectroscopy detection method with laser wavelength deviation detection provided in the first aspect of the present invention.

[0011] According to a fourth aspect of the present invention, a computer-readable medium is provided, on which a computer program is stored, wherein when the computer program is executed by a processor, the method for detecting photoacoustic spectroscopy with laser wavelength deviation detection provided in the first aspect of the present invention is implemented.

[0012] The beneficial effects of the present invention are: The invention relates to a detection method of photoacoustic spectrum with laser wavelength deviation detection, comprising: calibrating a Fabry-Perot etalon; controlling the cavity temperature of the calibrated Fabry-Perot etalon through dual-loop temperature control and PID control algorithm until the cavity temperature change reaches a threshold value within a preset time; coupling the temperature-controlled Fabry-Perot etalon with a photoacoustic signal source; detecting and collecting photoacoustic signals through a photoelectric detector, and denoising the photoacoustic signals through a second harmonic wavelength modulation method; and reconstructing the denoised photoacoustic signals based on compressed sensing and a two-step iterative shrinkage method.

[0013] It can be seen that the present invention has the following beneficial effects: 1. The dual-loop temperature control system and multi-layer thermal insulation structure are used to achieve high thermal stability of the Fabry-Perot interferometer. The temperature is adjusted in real time through the PID control algorithm to ensure the stability of the interferometer under different environmental conditions.

[0014] 2. Combined with silicon cantilever sensors, the second harmonic wavelength modulation technology (2f-WMS) is used to significantly improve the sensitivity and signal-to-noise ratio of photoacoustic signals. The precision and accuracy of detection are further improved through compressed sensing reconstruction methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 A schematic diagram of the basic flow of a photoacoustic spectroscopy detection method with laser wavelength deviation detection in some embodiments of the present invention; Figure 2 A schematic diagram of a specific process of a photoacoustic spectroscopy detection method with laser wavelength deviation detection in some embodiments of the present invention; Figure 3 It is a schematic diagram of the structure of a photoacoustic spectroscopy detection system with laser wavelength deviation detection in some embodiments of the present invention; Figure 4 It is a schematic diagram of the structure of an electronic device in some embodiments of the present invention. DETAILED DESCRIPTION

[0016] The principles and features of the present invention are described below in conjunction with the accompanying drawings. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0017] refer to Figure 1 and Figure 2 In a first aspect of the present invention, a detection method of photoacoustic spectroscopy with laser wavelength deviation detection is provided, comprising: S100. Calibrate a Fabry-Perot etalon based on a standard light source of multiple wavelengths of a target laser; S200. Control the cavity temperature of the calibrated Fabry-Perot etalon through a dual-loop temperature control and PID control algorithm until the cavity temperature change reaches a threshold within a preset time; S300. Couple the temperature-controlled Fabry-Perot etalon with a wavelength-tunable laser source, and then use the laser source to irradiate a photoacoustic cell; S400. Detect and collect photoacoustic signals through a photodetector, and denoise the photoacoustic signals through a second harmonic wavelength modulation method; S500. Reconstruct the denoised photoacoustic signals based on compressed sensing and a two-step iterative shrinkage method.

[0018] In step S100 of some embodiments of the present invention, the Fabry-Perot etalon is calibrated based on a standard light source of multiple wavelengths of the target laser. Specifically, a standard light source of known wavelength is used for calibration to ensure the accuracy of the system measurement; and the repeatability and stability of the system are verified by measuring lasers of different wavelengths multiple times.

[0019] It is understandable that the cavity temperature of the Fabry-Perot etalon has an important influence on its measurement accuracy. Temperature changes will cause changes in the cavity length, thus affecting the accuracy of wavelength measurement. In order to ensure the stability of the Fabry-Perot etalon under different environmental conditions, a dual-loop temperature control system and PID control algorithm are required to achieve precise control of the cavity temperature.

[0020] Therefore, in step S200 of some embodiments of the present invention, controlling the cavity temperature of the calibrated Fabry-Perot etalon by dual-loop temperature control and PID control algorithm until the cavity temperature changes to reach a threshold within a preset time includes: S201. The thermoelectric cooler and the temperature sensor are installed at multiple locations in the Fabry-Perot standard cavity to detect the cavity temperature in real time; Specifically, the dual-loop temperature control system includes two independent control loops: an inner loop and an outer loop. The inner loop controls the cold-side temperature of the thermoelectric cooler (TEC), and the outer loop controls the hot-side temperature of the TEC. Select a suitable TEC to ensure that it has sufficient cooling and heating capabilities to meet the temperature regulation requirements of the Fabry-Perot etalon cavity. Install high-precision temperature sensors (such as PT100 or NTC thermistors) at key locations of the Fabry-Perot etalon cavity to monitor the cavity temperature in real time. Select suitable PID controllers and TEC drivers to ensure that they are compatible and work efficiently with the temperature sensors and TEC.

[0021] S202. The thermal measurement temperature of the thermoelectric cooler is controlled by the outer loop PID controller, and after the thermal measurement temperature is stabilized, the cold measurement temperature of the thermoelectric cooler is controlled by the inner loop PID controller to be stable; S203. Set the cavity temperature of the Fabry-Perot etalon, and control the cavity temperature of the calibrated Fabry-Perot etalon through the stabilized outer loop PID controller and the inner loop PID controller until the cavity temperature changes to reach a threshold within a preset time.

[0022] Specifically, the proportional, integral and differential gain parameters of the PID controller are set by experiments or automatic tuning methods. K p 、K i 、K d , ensuring that the system responds quickly and stably.

[0023] Furthermore, the control method of the outer loop PID controller is expressed as: , u(t) Indicates the controller output regulation voltage; e(t) represents the temperature error, K p 、K i 、K d Respectively represent proportional gain, integral gain and differential gain. Similarly, the above control method can also be used to represent the control method of the inner loop PID controller, which will not be repeated here.

[0024] In step S400 of some embodiments of the present invention, denoising the photoacoustic signal by a second harmonic wavelength modulation method includes: S401. Synchronously detecting the phase difference between the photoacoustic signal and the reference signal through a lock-in amplifier, and extracting the second harmonic component of the photoacoustic signal; Specifically, a wavelength-tunable laser source is used to control the change of the laser wavelength by modulating the laser drive current. The modulation signal generation formula is: λ(t)=λ 0 +Δλsin(ωt) , in, λ(t) is the modulated laser wavelength, l 0 is the central wavelength, Dl is the modulation depth, and ω is the modulation angular frequency. The second harmonic signal is extracted by digital filtering and fast Fourier transform. A lock-in amplifier (LIA) is used to synchronously detect the phase difference between the input signal and the reference signal. The LIA can selectively amplify signals with the same frequency and phase as the reference signal to extract the second harmonic component. Configure the reference frequency and phase of the LIA to ensure that they are consistent with the laser wavelength modulation frequency. Adjust the gain and time constant of the LIA to optimize the signal detection performance.

[0025] S402. Calculate the intensity and distribution of the photoacoustic signal based on the amplitude and phase changes of the second harmonic component; S403. De-noise the photoacoustic signal based on the intensity and distribution of the photoacoustic signal. Specifically, the intensity and distribution of the photoacoustic signal are obtained, and a corresponding filter is set to de-noise the photoacoustic signal.

[0026] It can be understood that the microphone in the photoacoustic pool collects the acoustic signal and demodulates and processes the optical signal measured by the photodetector to finally obtain the photoacoustic signal.

[0027] In step S500 of some embodiments of the present invention, reconstructing the denoised photoacoustic signal based on compressed sensing and a two-step iterative shrinkage method includes: S501. Reconstructing the initial pressure distribution of the photoacoustic signal from the sparse measurement data by a compressed sensing method; Specifically, it is assumed that the photoacoustic signal has a sparse representation under a certain basis or dictionary, that is, most of the coefficients are zero or close to zero. Discrete cosine transform (DCT), wavelet transform, etc. can be used for sparse representation. Construct the measurement matrix A , which means that from the sparse signal x To measurement data y The linear transformation relationship of . That is: y=Ax+e, in e Indicates noise.

[0028] S502. The initial pressure distribution is updated and iterated by a two-step iterative shrinkage method until the soft threshold difference between adjacent iterative signals is lower than a preset value.

[0029] Specifically, the TwIST algorithm reconstructs the signal from sparse measurement data through an iterative optimization process. Initialization signal x(0) and x (1) , set the threshold parameters l , step size parameter α and β .

[0030] At each iteration, the signal is updated x Estimated value: , x (k+1) Indicates k+ Signal estimate for 1 iteration; x (k) Indicates k The signal estimate of the iteration; T λ Represents soft threshold ,l Represents the threshold parameter.

[0031] It should be noted that x Represents the input signal or data. The input signal can be a scalar, a vector or a matrix, which represents the coefficients in a certain basis. x The value of can be positive, negative, or zero. λ is a positive number that determines the degree to which the signal component is compressed. If x The absolute value of is less than l ,but x is compressed to zero, indicating that this component is considered to be noise or an unimportant signal; if x The absolute value of l ,but x Subtract l The part is retained, indicating that this component is considered to be an important signal component.

[0032] Furthermore, the soft threshold is calculated by the following steps: , in T Represents soft threshold ,l represents the threshold parameter, x represents the photoacoustic signal, and sign(x) represents the sign function. represents a compression operation. When |x|≤λ|, the output is zero, indicating that the signal component smaller than the threshold is completely suppressed. l |, the output is |x|−λ|, which means that the signal component greater than the threshold is retained, but its amplitude is reduced. l .

[0033] Furthermore, the input signal x contains noise, and the soft threshold function passes the threshold lThe signal components less than the threshold are compressed to zero, thereby removing noise. The soft threshold function retains important signal components and suppresses unimportant components through sparse representation of the signal, making the signal representation more sparse, which is helpful for signal compression and reconstruction. The soft threshold function is used for signal reconstruction in compressed sensing technology. By processing sparse signals, redundant data is reduced and the compression efficiency of the signal is improved.

[0034] Assume there is an input signal vector x =[3,1,−2,0.5,−0.1] and threshold parameters l =1, the result after applying the soft threshold function is as follows: for x =3, calculate sign(3)⋅max(3−1,0)=1⋅2=2; for x =1, calculate sign(1)⋅max(1−1,0)=1⋅0=0; for x =−2, calculate sign(−2)⋅max(2−1,0)=−1⋅1=−1; for x =0.5, calculate sign(0.5)⋅max(0.5−1,0)=1⋅0=0; for x =−0.1, calculate sign(−0.1)⋅max(0.1−1,0); Therefore, the output signal vector after applying the soft threshold function is [2,0,−1,0,0].

[0035] Finally, the reconstructed photoacoustic signal is analyzed to calculate the reconstruction accuracy and sparsity of the signal. The reconstruction effect is evaluated by comparing the reconstructed signal with the original signal.

[0036] The reconstruction accuracy is evaluated by the peak signal-to-noise ratio: ; The sparsity evaluation is expressed as: , Among them, Sparsity represents the sparsity of the signal; Represents the number of non-zero elements of the signal; N represents the total number of elements of the signal.

[0037] It can be understood that the denoised photoacoustic signal is reconstructed based on compressed sensing and two-step iterative shrinkage method. This method combines compressed sensing technology and efficient TwIST algorithm, which can reconstruct high-precision photoacoustic signals from sparse measurement data and improve the accuracy and stability of signal reconstruction.

[0038] Example 2 refer to Figure 3 In a second aspect of the present invention, a detection system 1 for photoacoustic spectroscopy with laser wavelength deviation detection is provided, comprising: a calibration module 11, used to calibrate a Fabry-Perot etalon based on a standard light source of multiple wavelengths of a target laser; a control module 12, used to control the cavity temperature of the calibrated Fabry-Perot etalon through a dual-loop temperature control and PID control algorithm until the cavity temperature change reaches a threshold value within a preset time; a coupling module 13, used to couple the temperature-controlled Fabry-Perot etalon with a wavelength-tunable laser source, and then use the laser source to irradiate a photoacoustic cell; a denoising module 14, used to detect and collect photoacoustic signals through a photodetector, and denoise the photoacoustic signals through a second harmonic wavelength modulation method; a reconstruction module 15, used to reconstruct the denoised photoacoustic signals based on compressed sensing and a two-step iterative shrinkage method.

[0039] Furthermore, the denoising module 14 includes: an extraction unit, which is used to synchronously detect the phase difference between the photoacoustic signal and the reference signal through a phase-locked amplifier, and extract the second harmonic component of the photoacoustic signal; a calculation unit, which is used to calculate the intensity and distribution of the photoacoustic signal based on the amplitude and phase changes of the second harmonic component; and a denoising unit, which is used to denoise the photoacoustic signal based on the intensity and distribution of the photoacoustic signal.

[0040] Example 3 refer to Figure 4 According to a third aspect of the present invention, an electronic device is provided, comprising: one or more processors; a storage device for storing one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors implement the photoacoustic spectroscopy detection method with laser wavelength deviation detection according to the first aspect of the present invention.

[0041] The electronic device 500 may include a processing device (e.g., a central processing unit, a graphics processing unit, etc.) 501, which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM) 502 or a program loaded from a storage device 508 into a random access memory (RAM) 503. In the RAM 503, various programs and data required for the operation of the electronic device 500 are also stored. The processing device 501, the ROM 502, and the RAM 503 are connected to each other via a bus 504. An input / output (I / O) interface 505 is also connected to the bus 504.

[0042] Typically, the following devices may be connected to the I / O interface 505: an input device 506 including, for example, a touch screen, a touch pad, a keyboard, a mouse, a camera, a microphone, an accelerometer, a gyroscope, etc.; an output device 507 including, for example, a liquid crystal display (LCD), a speaker, a vibrator, etc.; a storage device 508 including, for example, a hard disk, etc.; and a communication device 509. The communication device 509 may allow the electronic device 500 to communicate with other devices wirelessly or by wire to exchange data. Although Figure 4 The electronic device 500 is shown with various devices, but it should be understood that it is not required to implement or possess all the devices shown. More or fewer devices may be implemented or possessed instead. Figure 4 Each block shown in the figure may represent one device, or may represent multiple devices as required.

[0043] In particular, according to an embodiment of the present disclosure, the process described above with reference to the flowchart can be implemented as a computer software program. For example, an embodiment of the present disclosure includes a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program includes a program code for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from the network through a communication device 509, or installed from a storage device 508, or installed from a ROM 502. When the computer program is executed by the processing device 501, the above functions defined in the method of the embodiment of the present disclosure are executed. It should be noted that the computer-readable medium described in the embodiment of the present disclosure can be a computer-readable signal medium or a computer-readable storage medium or any combination of the above two. The computer-readable storage medium can be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or device, or any combination of the above. More specific examples of computer-readable storage media may include, but are not limited to, an electrical connection with one or more conductors, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In an embodiment of the present disclosure, a computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in combination with an instruction execution system, an apparatus, or a device. In an embodiment of the present disclosure, a computer-readable signal medium may include a data signal propagated in a baseband or as part of a carrier wave, in which a computer-readable program code is carried. Such propagated data signals may take a variety of forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. A computer-readable signal medium may also be any computer-readable medium other than a computer-readable storage medium, which may send, propagate, or transmit a program for use by or in combination with an instruction execution system, an apparatus, or a device. The program code embodied on the computer readable medium may be transmitted using any appropriate medium, including but not limited to: wires, optical cables, RF (radio frequency), etc., or any suitable combination of the foregoing.

[0044] The computer-readable medium may be included in the electronic device, or may exist independently without being installed in the electronic device. The computer-readable medium carries one or more computer programs. When the one or more programs are executed by the electronic device, the electronic device: Computer program code for performing the operations of embodiments of the present disclosure may be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages, such as Java, Smalltalk, C++, Python, and conventional procedural programming languages, such as "C" or similar programming languages. The program code may be executed entirely on a user's computer, partially on a user's computer, as a separate software package, partially on a user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving a remote computer, the remote computer may be connected to the user's computer via any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0045] The flow chart and block diagram in the accompanying drawings illustrate the possible architecture, function and operation of the system, method and computer program product according to various embodiments of the present disclosure. In this regard, each box in the flow chart or block diagram can represent a module, a program segment or a part of a code, and the module, the program segment or a part of the code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should be noted that each box in the block diagram and / or flow chart, and the combination of the boxes in the block diagram and / or flow chart can be implemented with a dedicated hardware-based system that performs a specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0046] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for detecting photoacoustic spectroscopy with laser wavelength deviation detection, characterized in that: include: Calibrate the Fabry-Perot etalon based on standard light sources with multiple wavelengths of target lasers; The cavity temperature of the calibrated Fabry-Perot etalon is controlled by dual-loop temperature control and PID control algorithm until the cavity temperature changes to a threshold value within a preset time; The temperature-controlled Fabry-Perot etalon is coupled to a wavelength-tunable laser source, and then the laser source is used to illuminate the photoacoustic cell; Detecting and collecting photoacoustic signals by means of a photodetector, and denoising the photoacoustic signals by means of a second harmonic wavelength modulation method; The denoised photoacoustic signal is reconstructed based on compressed sensing and a two-step iterative shrinkage method.

2. The photoacoustic spectroscopy detection method with laser wavelength deviation detection according to claim 1, characterized in that: The step of controlling the cavity temperature of the calibrated Fabry-Perot etalon by using the dual-loop temperature control and PID control algorithm until the cavity temperature changes to a threshold value within a preset time includes: Thermoelectric coolers and temperature sensors are installed at multiple locations in the Fabry-Perot etalon cavity to detect the cavity temperature in real time; The hot measurement temperature of the thermoelectric cooler is controlled by an outer loop PID controller, and after the hot measurement temperature is stabilized, the cold measurement temperature of the thermoelectric cooler is controlled by an inner loop PID controller to be stable; The cavity temperature of the Fabry-Perot etalon is set, and the cavity temperature of the calibrated Fabry-Perot etalon is controlled by the stabilized outer loop PID controller and the inner loop PID controller until the cavity temperature changes to reach a threshold within a preset time.

3. The photoacoustic spectroscopy detection method with laser wavelength deviation detection according to claim 2, characterized in that: The control method of the outer loop PID controller is expressed as: ， u(t) Indicates the controller output regulation voltage; e(t) represents the temperature error, K p 、K i 、K d They represent proportional gain, integral gain and differential gain respectively.

4. The photoacoustic spectroscopy detection method with laser wavelength deviation detection according to claim 1, characterized in that: The denoising of the photoacoustic signal by the second harmonic wavelength modulation method comprises: The phase difference between the photoacoustic signal and the reference signal is synchronously detected by a phase-locked amplifier, and the second harmonic component of the photoacoustic signal is extracted; Calculate the intensity and distribution of the photoacoustic signal based on the amplitude and phase changes of the second harmonic component; The photoacoustic signal is denoised based on the intensity and distribution of the photoacoustic signal.

5. The photoacoustic spectroscopy detection method with laser wavelength deviation detection according to claim 1, characterized in that: The method of reconstructing the denoised photoacoustic signal based on compressed sensing and a two-step iterative shrinkage method includes: The initial pressure distribution of the photoacoustic signal is reconstructed from the sparse measurement data by using the compressed sensing method; The initial pressure distribution is updated and iterated by a two-step iterative shrinkage method until the soft threshold difference between adjacent iterative signals is lower than a preset value.

6. The photoacoustic spectroscopy detection method with laser wavelength deviation detection according to claim 5, characterized in that: The soft threshold is calculated by the following steps: ， in T Represents soft threshold ,λ represents the threshold parameter, x represents the photoacoustic signal, and sign(x) represents the sign function.

7. A photoacoustic spectroscopy detection system with laser wavelength deviation detection, characterized in that: include: A calibration module, used to calibrate the Fabry-Perot etalon based on a standard light source with multiple wavelengths of the target laser; A control module, used to control the cavity temperature of the calibrated Fabry-Perot etalon through dual-loop temperature control and PID control algorithm until the cavity temperature changes to reach a threshold within a preset time; A coupling module, used to couple the temperature-controlled Fabry-Perot etalon with a wavelength-tunable laser source, and then use the laser source to irradiate the photoacoustic cell; A denoising module, used for detecting and collecting photoacoustic signals through a photodetector, and denoising the photoacoustic signals through a second harmonic wavelength modulation method; The reconstruction module is used to reconstruct the denoised photoacoustic signal based on compressed sensing and a two-step iterative shrinkage method.

8. The photoacoustic spectroscopy detection system with laser wavelength deviation detection according to claim 7, characterized in that: The denoising module comprises: An extraction unit, used to synchronously detect the phase difference between the photoacoustic signal and the reference signal through a phase-locked amplifier, and extract the second harmonic component of the photoacoustic signal; A calculation unit, used for calculating the intensity and distribution of the photoacoustic signal based on the amplitude and phase changes of the second harmonic component; A denoising unit is used to denoise the photoacoustic signal based on the intensity and distribution of the photoacoustic signal.

9. An electronic device, comprising: one or more processors; A storage device for storing one or more programs, which, when executed by the one or more processors, enables the one or more processors to implement the photoacoustic spectroscopy detection method with laser wavelength deviation detection as described in any one of claims 1 to 6.

10. A computer readable medium having a computer program stored thereon, wherein: When the computer program is executed by a processor, the method for detecting photoacoustic spectroscopy with laser wavelength deviation detection according to any one of claims 1 to 6 is implemented.

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