Coherent anti-Stokes Raman spectroscopy measurement system and method based on dual optical frequency comb

Abstract

The present application discloses a coherent anti-Stokes Raman spectroscopy measurement system and method based on a dual optical frequency comb. The present application adjusts the optical frequency comb repetition frequency parameter of a first pulse emission module or a second pulse emission module so that the optical frequency comb repetition frequency difference between the first pulse emission module and the second pulse emission module does not exceed the repetition frequency difference threshold value, and enhances the signal-to-noise ratio of spectral acquisition by selecting a suitable dual optical frequency comb repetition frequency parameter range. Then, when a non-resonant four-wave mixing background of a certain intensity is detected by a photoelectric detection element, a signal acquisition trigger instruction is sent to a spectral acquisition module, so that after receiving the signal acquisition trigger instruction, the spectral acquisition module waits for a preset waiting time and waits for the four-wave mixing background light signal to weaken before acquiring the spectral signal of the pulsed laser, thereby solving the technical problem that the existing coherent anti-Stokes Raman spectroscopy measurement causes spectral data acquisition and measurement difficulties due to non-resonant four-wave mixing interference.

Description

Technical Field

[0001] The present application relates to the field of optical technology, and in particular to a coherent anti-Stokes Raman spectroscopy measurement system and method based on a dual optical frequency comb. Background Art

[0002] Raman scattering spectroscopy is widely used in chemical analysis, chemical substance detection, biomedical imaging and other fields. Coherent Raman scattering is a technology that uses ultrafast laser pulse technology to improve the signal-to-noise ratio of Raman spectroscopy. Coherent anti-Stokes Raman scattering is a nonlinear optical process based on Raman scattering of laser pulse four-wave mixing. It requires three beams of light to work together to produce coherent Raman signals. These three beams are called pump light, Stokes light, and probe light. Ultrafast pulsed light is generally used to produce coherent anti-Stokes Raman scattering. Because the intensity of the pulsed light is high, the nonlinearity is stronger, and the coherent Raman scattering signal generated is also stronger. Since pulsed lasers are used, it is necessary to ensure that the pulsed lasers coincide in time to produce coherent Raman scattering. However, for coherent anti-Stokes Raman, in addition to Raman scattering, there will also be a non-resonant four-wave mixing background. This background is generated when the three beams of light coincide, and the intensity of non-resonant four-wave mixing is generally very strong, which will drown out the Raman signal light and affect the collection of coherent Raman spectra. Summary of the invention

[0003] The present application provides a coherent anti-Stokes Raman spectroscopy measurement system and method, which are used to solve the technical problem that the existing coherent anti-Stokes Raman spectroscopy measurement is difficult to collect and measure spectral data due to non-resonant four-wave mixing interference.

[0004] In order to solve the above technical problems, the first aspect of the present application provides a coherent anti-Stokes Raman spectroscopy measurement system, comprising: a dual optical frequency comb pulse light source, a beam splitter group, a convex lens group, a first photoelectric detection element, a filter, and a spectrum acquisition module;

[0005] The dual optical frequency comb pulse light source comprises: a first pulse emission module, a second pulse emission module and a frequency adjustment module, wherein the first pulse emission module and the second pulse emission module are both used to emit pulse lasers according to their respective optical frequency comb repetition frequency parameters, and the frequency adjustment module is configured to: according to a preset repetition frequency difference threshold, adjust the optical frequency comb repetition frequency parameter of the first pulse emission module or the second pulse emission module, so that the optical frequency comb repetition frequency difference between the first pulse emission module and the second pulse emission module does not exceed the repetition frequency difference threshold;

[0006] The beam splitter group is used to adjust the laser optical path output by the dual optical frequency comb pulse light source so that the two pulse lasers output by the dual optical frequency comb pulse light source intersect and are then respectively connected to the spectrum acquisition module and the first photoelectric detection element optical path;

[0007] The convex lens group and the filter are sequentially arranged on the optical path between the intersection of the pulse laser and the spectrum acquisition module, wherein the convex lens group comprises: two convex lens sheets arranged at intervals, and the space between the two convex lens sheets is used to place the sample;

[0008] The first data communication port of the first photoelectric detection element is communicatively connected to the first data communication port of the spectral acquisition module, wherein the first photoelectric detection element is configured to send a signal acquisition trigger instruction to the spectral acquisition module when the intensity of the received pulsed laser reaches a preset intensity threshold, and the spectral acquisition module is configured to acquire the spectral signal of the pulsed laser after a preset waiting time after receiving the signal acquisition trigger instruction.

[0009] Preferably, the first pulse emission module is a femtosecond pulse emission module, and the second pulse emission module is a picosecond pulse emission module.

[0010] Preferably, the waiting time is not less than 1 μs.

[0011] Preferably, the spectrum acquisition module specifically includes: a second photoelectric detection element or a spectrometer.

[0012] Preferably, when the spectrum acquisition module is a second photoelectric detection element, the filter is specifically a narrow-band filter.

[0013] The second aspect of the present application provides a control method for a coherent anti-Stokes Raman spectroscopy measurement system, which is applied to a coherent anti-Stokes Raman spectroscopy measurement system provided in the first aspect of the present application, and the control method includes:

[0014] The frequency adjustment module in the dual optical frequency comb pulse light source adjusts the optical frequency comb repetition frequency parameter of the first pulse emission module or the second pulse emission module according to a preset repetition frequency difference threshold, so that the optical frequency comb repetition frequency difference between the first pulse emission module and the second pulse emission module does not exceed the repetition frequency difference threshold;

[0015] The first pulse emission module and the second pulse emission module in the dual optical frequency comb pulse light source emit pulse lasers according to their respective optical frequency comb repetition frequency parameters;

[0016] When the intensity of the pulsed laser received by the first photoelectric detection element reaches a preset intensity threshold, the first photoelectric detection element sends a signal acquisition trigger instruction to the spectrum acquisition module;

[0017] When the spectrum acquisition module receives the signal acquisition trigger instruction, the spectrum acquisition module acquires the spectrum signal of the pulse laser after a preset waiting time.

[0018] Preferably, the first pulse emission module is a femtosecond pulse emission module, and the second pulse emission module is a picosecond pulse emission module.

[0019] Preferably, the waiting time is not less than 1 μs.

[0020] Preferably, the spectrum acquisition module specifically includes: a second photoelectric detection element or a spectrometer.

[0021] Preferably, when the spectrum acquisition module is a second photoelectric detection element, the filter is specifically a narrow-band filter.

[0022] It can be seen from the above technical solutions that the embodiments of the present application have the following advantages:

[0023] The coherent anti-Stokes Raman spectroscopy measurement system provided by the present application adjusts the optical frequency comb repetition frequency parameter of the first pulse emission module or the second pulse emission module according to a preset repetition frequency difference threshold value, so that the optical frequency comb repetition frequency difference between the first pulse emission module and the second pulse emission module does not exceed the repetition frequency difference threshold value, and enhances the signal-to-noise ratio of spectral acquisition by selecting a suitable dual optical frequency comb repetition frequency parameter range. Then, when a certain intensity of non-resonant four-wave mixing background is detected by a photoelectric detection element, a signal acquisition trigger instruction is sent to the spectral acquisition module, so that after receiving the signal acquisition trigger instruction, the spectral acquisition module waits for a preset waiting time and waits for the four-wave mixing background light signal to weaken before acquiring the spectral signal of the pulsed laser, thereby solving the technical problem that the existing coherent anti-Stokes Raman spectroscopy measurement causes difficulties in spectral data acquisition and measurement due to non-resonant four-wave mixing interference. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0025] Figure 1 A schematic structural diagram of an embodiment of a coherent anti-Stokes Raman spectroscopy measurement system provided in the present application.

[0026] Figure 2 A schematic structural diagram of another embodiment of a coherent anti-Stokes Raman spectroscopy measurement system provided in the present application.

[0027] Figure 3 A schematic flow chart of a control method for a coherent anti-Stokes Raman spectroscopy measurement system provided in the present application.

[0028] In the figure, the accompanying drawings are marked as follows:

[0029] A1, dual frequency comb pulse light source; A11, first pulse emission module; A12, second pulse emission module; A13, frequency adjustment module; A2, beam splitter; A3, photoelectric detection element; A4, spectrum acquisition module; A5, convex lens; A6, sample; A7, filter. DETAILED DESCRIPTION

[0030] The embodiments of the present application provide a coherent anti-Stokes Raman spectroscopy measurement system and method based on a dual optical frequency comb, which is used to solve the technical problem that the existing coherent anti-Stokes Raman spectroscopy measurement is difficult to collect and measure spectral data due to non-resonant four-wave mixing interference.

[0031] In order to make the purpose, features, and advantages of the invention of this application more obvious and easy to understand, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the embodiments described below are only part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0032] The explanations of some professional terms mentioned in this embodiment are as follows:

[0033] An optical frequency comb is a spectrum consisting of a series of frequency components that are evenly spaced and have a coherent and stable phase relationship.

[0034] Dual frequency comb refers to an optical technology that uses two optical frequency combs with different repetition frequencies to perform spectral measurements.

[0035] The repetition rate refers to how often the laser pulses repeat in the time domain.

[0036] Raman spectroscopy is an inelastic scattering spectrum generated by molecular vibration energy levels and can be used to identify different molecules.

[0037] Stokes light refers to the reflected light with a frequency lower than the incident light generated in Raman scattering, and the corresponding anti-Stokes light refers to the scattered light with a frequency higher than the incident light.

[0038] Coherent Raman spectroscopy refers to Raman scattering caused by the coherence of molecular vibration energy levels. It is characterized by directionality and coherence, so the signal-to-noise ratio is much higher than spontaneous Raman.

[0039] Wavenumber is a common frequency unit for Raman scattering. The wavelength of Raman scattering relative to the frequency difference of the incident light is generally described by wavenumber. The unit can also be expressed as cm-1, which is approximately equal to 30GHz.

[0040] Coherent anti-Stokes Raman scattering is a nonlinear optical process that requires three beams of light to work together to produce a coherent Raman signal. Therefore, ultrafast pulsed light is generally used to produce coherent anti-Stokes Raman scattering. Because the intensity of the pulsed light is high, the nonlinearity is stronger and the coherent Raman scattering signal generated is also stronger. Since pulsed lasers are used, it is necessary to ensure that the pulsed lasers coincide in time to produce coherent Raman scattering. For coherent anti-Stokes Raman, in addition to Raman scattering, there will also be a non-resonant four-wave mixing background. This background is generated when the three beams of light coincide. In Raman, these three beams of light are called pump light, Stokes light, and probe light. The intensity of non-resonant four-wave mixing is generally very strong and will drown out the Raman signal light. Therefore, in general, some spectral techniques, such as Fourier operation processing, are needed to weaken this non-resonant four-wave mixing background, thereby improving the signal-to-noise ratio of the Raman signal. A commonly used technique is to ensure that the pump light and the Stokes light coincide in time, but the probe light has an experimental delay of several picoseconds. This can weaken non-resonant four-wave mixing, and because the decoherence time of molecular vibrational energy levels is generally more than a picosecond, the probe light can produce coherent anti-Stokes Raman scattering through the coherence of vibrational energy levels.

[0041] See also Figure 1 and Figure 2 In a first aspect, the present application provides a coherent anti-Stokes Raman spectroscopy measurement system based on a dual optical frequency comb, comprising: a dual optical frequency comb pulse light source A1, a beam splitter group, a convex lens group, a first photoelectric detection element A3, a filter A7 and a spectrum acquisition module A4;

[0042] The dual optical frequency comb pulse light source A1 comprises: a first pulse emission module A11, a second pulse emission module A12 and a frequency adjustment module A13, wherein the first pulse emission module A11 and the second pulse emission module A12 are both used to emit pulse lasers according to their respective optical frequency comb repetition frequency parameters, and the frequency adjustment module A13 is configured to: according to a preset repetition frequency difference threshold, adjust the optical frequency comb repetition frequency parameter of the first pulse emission module A11 or the second pulse emission module A12, so that the optical frequency comb repetition frequency difference between the first pulse emission module A11 and the second pulse emission module A12 does not exceed the repetition frequency difference threshold;

[0043] A beam splitter group, comprising a plurality of beam splitters A2, used to adjust the laser optical path output by the dual-frequency comb pulse light source A1, so that the two pulse lasers output by the dual-frequency comb pulse light source A1 intersect, and then are respectively connected to the spectrum acquisition module A4 and the first photoelectric detection element A3 optical path;

[0044] The convex lens group and the filter A7 are sequentially arranged on the optical path between the intersection of the pulse laser and the spectrum acquisition module A4, wherein the convex lens group includes: two convex lens lenses A5 arranged at intervals, and the sample A6 is placed between the two convex lens lenses A5;

[0045] The first data communication port of the first photoelectric detection element A3 is communicatively connected to the first data communication port of the spectral acquisition module A4, wherein the first photoelectric detection element A3 is configured to send a signal acquisition trigger instruction to the spectral acquisition module A4 when the intensity of the received pulsed laser reaches a preset intensity threshold, and the spectral acquisition module A4 is configured to acquire the spectral signal of the pulsed laser after a preset waiting time after receiving the signal acquisition trigger instruction.

[0046] Furthermore, the first pulse emission module A11 is a femtosecond pulse emission module, and the second pulse emission module A12 is a picosecond pulse emission module.

[0047] It should be noted that the traditional scheme requires three laser beams, while this embodiment selects a simplified scheme that can use two laser pulses. The pump light and the Stokes light can be provided by a very short but sufficiently wide frequency femtosecond pulse. The femtosecond pulse needs to be wide enough in the frequency domain to cover the frequencies of the pump light and the Stokes light. For example, for the case where the Raman frequency moves at 1000 wave numbers, the pulse time width is about 10fs, and for the case where the Raman frequency moves at 3000 wave numbers, the pulse time width is 5fs. However, for the detection light, this embodiment selects picosecond pulses, because picosecond pulses are relatively narrow in frequency, which can ensure the spectral resolution of the Raman spectrum.

[0048] Furthermore, the waiting time is specifically not less than 1 μs.

[0049] Furthermore, the spectrum acquisition module A4 specifically includes: a second photoelectric detection element or a spectrometer.

[0050] Further, when the spectrum acquisition module A4 is the second photoelectric detection element, the filter A7 is specifically a narrow-band filter A7.

[0051] In this embodiment, the spectrum acquisition module A4 preferably uses a spectrometer to directly acquire the spectrum, but a photoelectric detection element, such as a photoelectric detection sensor, may also be used when acquiring the spectrum. Since the photoelectric detector itself does not have spectral resolution, when the spectrum acquisition module A4 uses a photoelectric detection element, a narrowband filter A7 is required to filter the signal light to obtain the spectrum line to be observed, thereby detecting the coherent Raman signal.

[0052] This embodiment uses a dual optical frequency comb, and sets the repetition frequency difference of the dual optical frequency combs so that the time scanning step of the dual optical frequency combs is ten femtoseconds. Taking an 80MHz optical frequency comb as an example, the repetition frequency of the other optical frequency comb is 80.00007MHz. At this time, the time scanning step between the two optical frequency combs is 10.5fs. Considering that the output light of the dual optical frequency comb is Gaussian light, if the time width of the detection light is 1ps, the spectral resolution is about 14 wavenumbers, and the waiting time is 1.25μs. If the time width of the detection light is 2ps, the spectral resolution is about 7 wavenumbers, and the waiting time is 2.5μs. If it is a 1GHz optical frequency comb, the repetition frequency of the other optical frequency comb is 1.000005GHz. In the pump optical frequency comb, the pulse width is 10fs. If the width of the detection optical frequency comb is about 2ps, the spectral resolution is about 7 wavenumbers, and the shortest waiting time is 0.4μs. Femtosecond pulses are used as excitation light to excite the coherence of Raman vibration energy levels, and detection light is used to detect the coherence of Raman vibration energy levels and generate coherent anti-Stokes Raman scattering. When the two pulses overlap in time, a non-resonant four-wave mixing background will be generated. In this embodiment, a wave splitter is placed in the optical path to separate a part of the light, and it is incident on a photodetector to generate a trigger signal for a spectrometer. When four-wave mixing is generated, the electrical signal generated on the photodetector will be strong enough, and then the incident light power is adjusted to ensure that the voltage generated by the four-wave mixing on the photodetector is around 5V. And use this signal to trigger the spectrometer. For a general spectrometer, the time interval between receiving the trigger signal and starting to record data is about 1μs, and the minimum can be 1μs. Considering the parameters of 80MHz repetition rate laser, 1ps detection light time width, and 14 wavenumbers of spectral resolution, the time for the two optical frequency combs to generate sufficiently strong four-wave mixing is about 1.25μs, so the waiting time can be set to 1.25μs. For the waiting time setting under other parameters, the time for generating four-wave mixing can also be adjusted to match the waiting time of the spectrometer. Therefore, after the preset waiting time of the spectrometer, the four-wave mixing generated will be very weak because the two pulses will not overlap in time. However, the decoherence time of the vibration energy level is relatively long, much greater than 1ps, so it will still generate sufficiently strong Raman. The decoherence time that can generate Raman signals is about 5 picoseconds. For the dual optical frequency comb with a scanning step of 10fs, the corresponding integration time of the spectrometer is 6μs, which will enhance the signal-to-noise ratio of the spectrum acquisition. If the repetition frequency difference of the dual frequency comb is further reduced, the integration time of the spectrometer will continue to increase, thereby improving the signal-to-noise ratio of the obtained signal. For a dual optical frequency comb with a repetition frequency of 80 MHz and 80.00007 MHz, the cycle time is about 15 ms, so we can set the acquisition time of the spectrometer to 10 ms. After each acquisition, we can wait for the next spectrometer acquisition trigger signal.

[0053] The above content is a detailed description of an embodiment of a coherent anti-Stokes Raman spectroscopy measurement system provided by the present application. The following is a detailed description of an embodiment of a control method for a coherent anti-Stokes Raman spectroscopy measurement system provided by the present application.

[0054] like Figure 3 As shown, the second embodiment of the present application provides a control method for a coherent anti-Stokes Raman spectroscopy measurement system based on a dual optical frequency comb, which is applied to a coherent anti-Stokes Raman spectroscopy measurement system provided in the first embodiment of the present application, and the control method includes:

[0055] S1. The frequency adjustment module in the dual optical frequency comb pulse light source adjusts the optical frequency comb repetition frequency parameter of the first pulse emission module or the second pulse emission module according to a preset repetition frequency difference threshold, so that the optical frequency comb repetition frequency difference between the first pulse emission module and the second pulse emission module does not exceed the repetition frequency difference threshold;

[0056] S2, the first pulse transmitting module and the second pulse transmitting module in the dual optical frequency comb pulse light source transmit pulse lasers according to their respective optical frequency comb repetition frequency parameters;

[0057] S3, when the intensity of the pulsed laser received by the first photoelectric detection element reaches a preset intensity threshold, the first photoelectric detection element sends a signal collection trigger instruction to the spectrum collection module;

[0058] S4. When the spectrum acquisition module receives the signal acquisition trigger instruction, the spectrum acquisition module acquires the spectrum signal of the pulse laser after a preset waiting time.

[0059] Furthermore, the first pulse emission module is a femtosecond pulse emission module, and the second pulse emission module is a picosecond pulse emission module.

[0060] Furthermore, the waiting time is specifically not less than 1 μs.

[0061] Furthermore, the spectrum acquisition module specifically includes: a second photoelectric detection element or a spectrometer.

[0062] Further, when the spectrum collection module is the second photoelectric detection element, the filter is specifically a narrow-band filter.

[0063] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0064] Unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0065] In the several embodiments provided in the present application, it should be understood that the disclosed terminals, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic, for example, the division of units is only a logical function division, and there may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or units, which can be electrical, mechanical or other forms.

[0066] The terms "first", "second", "third", "fourth", etc. (if any) in the specification of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can, for example, be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0067] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0068] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0069] As described above, the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A coherent anti-Stokes Raman spectroscopy measurement system based on dual optical frequency combs, characterized in that: include: Dual optical frequency comb pulse light source, beam splitter group, convex lens group, first photoelectric detection element, filter and spectrum acquisition module; The dual optical frequency comb pulse light source comprises: a first pulse emission module, a second pulse emission module and a frequency adjustment module, wherein the first pulse emission module and the second pulse emission module are both used to emit pulsed lasers according to their respective optical frequency comb repetition frequency parameters, and the frequency adjustment module is configured to: according to a preset repetition frequency difference threshold, adjust the optical frequency comb repetition frequency parameter of the first pulse emission module or the second pulse emission module, so that the optical frequency comb repetition frequency difference between the first pulse emission module and the second pulse emission module does not exceed the repetition frequency difference threshold, wherein the first pulse emission module is a femtosecond pulse emission module, and the second pulse emission module is a picosecond pulse emission module; The beam splitter group is used to adjust the laser optical path output by the dual optical frequency comb pulse light source so that the two pulse lasers output by the dual optical frequency comb pulse light source intersect and are then respectively connected to the spectrum acquisition module and the first photoelectric detection element optical path; The convex lens group and the filter are sequentially arranged on the optical path between the intersection of the pulse laser and the spectrum acquisition module, wherein the convex lens group comprises: two convex lens sheets arranged at intervals, and the space between the two convex lens sheets is used to place the sample; The first data communication port of the first photoelectric detection element is communicatively connected to the first data communication port of the spectral acquisition module, wherein the first photoelectric detection element is configured to send a signal acquisition trigger instruction to the spectral acquisition module when the intensity of the received pulsed laser reaches a preset intensity threshold, and the spectral acquisition module is configured to acquire the spectral signal of the pulsed laser after a preset waiting time after receiving the signal acquisition trigger instruction, wherein the waiting time is specifically not less than 1μs.

2. The coherent anti-Stokes Raman spectroscopy measurement system based on dual optical frequency comb according to claim 1, characterized in that: The spectrum acquisition module specifically includes: a second photoelectric detection element or a spectrometer.

3. The coherent anti-Stokes Raman spectroscopy measurement system based on dual optical frequency comb according to claim 2, characterized in that: When the spectrum acquisition module is a second photoelectric detection element, the filter is specifically a narrow-band filter.

4. A control method for a coherent anti-Stokes Raman spectroscopy measurement system based on a dual optical frequency comb, applied to a coherent anti-Stokes Raman spectroscopy measurement system based on a dual optical frequency comb as claimed in any one of claims 1 to 3, characterized in that: The control method comprises: The frequency adjustment module in the dual optical frequency comb pulse light source adjusts the optical frequency comb repetition frequency parameter of the first pulse emission module or the second pulse emission module according to a preset repetition frequency difference threshold, so that the optical frequency comb repetition frequency difference between the first pulse emission module and the second pulse emission module does not exceed the repetition frequency difference threshold, wherein the first pulse emission module is a femtosecond pulse emission module and the second pulse emission module is a picosecond pulse emission module; The first pulse emission module and the second pulse emission module in the dual optical frequency comb pulse light source emit pulse lasers according to their respective optical frequency comb repetition frequency parameters; When the intensity of the pulsed laser received by the first photoelectric detection element reaches a preset intensity threshold, the first photoelectric detection element sends a signal acquisition trigger instruction to the spectrum acquisition module; When the spectrum acquisition module receives the signal acquisition trigger instruction, the spectrum acquisition module acquires the spectrum signal of the pulse laser after a preset waiting time, and the waiting time is specifically not less than 1 μs.

5. The control method of the coherent anti-Stokes Raman spectroscopy measurement system based on dual optical frequency comb according to claim 4, characterized in that: The spectrum acquisition module specifically includes: a second photoelectric detection element or a spectrometer.

6. The control method of the dual optical frequency comb based coherent anti-Stokes Raman spectroscopy measurement system according to claim 5, characterized in that: When the spectrum collection module is a second photoelectric detection element, the filter is specifically a narrow-band filter.

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