Measurement method and system for multi-laser cooperative detection of nanobubbles

Abstract

The invention discloses a measurement method and system for multi-laser cooperative detection of nanobubbles, and belongs to the technical field of nanobubble measurement and detection. Through the excitation-detection double-laser system, key data such as the size, the service life and the formation threshold value of the nanobubbles are obtained in real time, the limitation of the traditional optical microscopic imaging resolution ratio is broken through, and the measurement precision is improved. Time-resolved imaging and thermal lens measurement are combined to realize omnibearing bubble monitoring. A time-resolved imaging technology is adopted to obtain information such as nucleation and collapse change of the nanobubbles. And in combination with thermal lens effect measurement, multi-angle measurement is realized. The generation of nano bubbles is accurately regulated and controlled, and laser processing and biological application are optimized. By adjusting parameters, controllable generation of nano bubbles is optimized, and the method is suitable for laser micromachining, microfluidic control, biomarking and other applications. In addition, the method is non-contact optical measurement, electrode or other external intervention is not needed, and the applicability is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of nano - bubble measurement and detection, and particularly to a measurement method and system for co - detecting nano - bubbles with multiple lasers. Background Art

[0002] Nano - bubbles have important applications in fields such as microfluidics, biomedicine, optical sensing, and material processing, and show unique advantages especially in photothermal therapy, micro - scale mass transfer, and surface micro - machining. Gold nanoparticles are widely used in the process of laser - induced bubble generation due to their excellent photothermal conversion ability and plasmon resonance characteristics. However, the formation and growth of nano - bubbles are affected by multiple factors, including laser energy density, physical properties of the liquid (such as viscosity, surface tension), and the size and distribution of nanoparticles. Therefore, accurately measuring the growth threshold and size of nano - bubbles is crucial for understanding bubble dynamics, optimizing laser parameters, and improving the controllability of nano - bubble - related applications.

[0003] Currently, common nano - bubble measurement methods include high - speed optical microscopy, light - scattering analysis, and ultrasonic detection, etc. Among them, high - speed optical imaging technology can be used to observe the nucleation and growth process of bubbles in real time, but it is limited by resolution and imaging frame rate and is difficult to accurately characterize the evolution of nano - scale bubbles. Ultrasonic measurement is suitable for the detection of larger bubbles, but has low detection sensitivity for nano - scale bubbles. Optical interference technology can be used to measure nano - scale bubbles, but it requires a high - precision coherent light source and interferometer system, and the experimental complexity is high. In addition, the formation threshold of laser - induced bubbles is a key parameter affecting their applications. For example, in laser precision machining, the generation of nano - bubbles affects the material removal efficiency and surface quality; in biomedical applications, the size of nano - bubbles determines their role in drug delivery and photothermal therapy. However, traditional measurement methods are usually limited to single measurement means, lack real - time monitoring and precise control of the nano - bubble formation process, and are difficult to achieve a comprehensive analysis of the nano - bubble growth process. Therefore, achieving high - precision, real - time measurement of the generation threshold and size of nano - bubbles, and combining laser parameter optimization to improve the controllability of bubbles, is an important challenge faced by current research.

[0004] For example, a Chinese invention patent with the publication number CN114654116A discloses a nano-hole fixed-point processing device and method for optical drive nanoparticles. The device includes a laser, a three-dimensional displacement control console, and a Raman signal detector; a substrate sample attached with gold nanoparticles is placed on the three-dimensional displacement control console. The laser emits laser light that sequentially passes through a short-wave cut-off filter and an objective lens to irradiate the gold nanoparticles. By adjusting the energy density of the laser and the incident angle of the focused laser, the size and movement direction of the nano-bubbles generated by precisely controlling the gold nanoparticles as the gasification core are controlled. The Raman signal detector is arranged directly above the processed sample to analyze the Raman spectrum for characterizing the local processing temperature and structural characteristics of the sample substrate. The power and wavelength parameters of the laser and the size of the gold nanoparticles are adjusted in real time to achieve the thermal processing of nanostructures with different sizes. This invention realizes the precise control processing of gold-nanoparticle-assisted picosecond laser beyond the diffraction limit, as well as real-time sample temperature detection and control and in-situ structure detection. However, this solution mainly focuses on gold-nanoparticle-assisted laser nano-processing. By adjusting the laser energy density and incident angle, the control of the bubble size and movement direction is achieved, and the Raman detection is used to feedback the processing temperature. Its core application is structure processing and characterization, lacking a real-time measurement mechanism during the generation process of individual nano-bubbles, especially unable to achieve dynamic precise monitoring in terms of the optical detection path and multi-laser collaborative measurement.

[0005] A Chinese invention patent with the publication number CN118706814A provides a device and method for optical drive droplet manipulation based on pump-probe. The device includes a three-dimensional displacement control console, a substrate, a laser driving mechanism, and a pump-probe mechanism. The laser driving mechanism includes a picosecond laser source, and the pump-probe mechanism includes a Raman laser source, a synchronous signal controller, a Raman signal detector, and an imaging system. The picosecond laser is used to drive the droplets of the gold nanoparticle solution to move directionally. At the same time, the picosecond laser acts as a pump light to excite the gold nanoparticles to the excited state. The Raman laser acts as a probe light and lags behind the picosecond laser. The Raman signal detector is used to detect the Raman scattering signal to obtain the temperature information of the gold nanoparticles. The imaging system is used to obtain the movement information of the droplets of the gold nanoparticle solution. This application combines droplet optical drive with pump-probe technology to detect the temperature and movement of the gold nanoparticles in the droplet while realizing droplet driving, and can adjust the movement of the droplet in a timely manner. However, it focuses on the movement and temperature evolution of gold nanoparticles in the droplet scale system. Its measurement object is the overall droplet, and the detection laser and the excitation laser are in a macroscopic delay mode in time control, unable to capture the rapid phase change process at the nano-bubble level and not having the ability to accurately extract single-bubble parameters (such as threshold, size, lifetime) with high spatio-temporal resolution.

[0006] In addition, the Chinese invention patent with the publication number CN119375108A discloses a method for detecting the concentration and particle size of nano-bubble water based on light scattering. An experiment for preparing nano-bubble water on the ground is carried out to measure the gas consumption, water consumption and the amount of generated nano-bubble water used for preparing nano-bubble water. By sequentially irradiating the prepared nano-bubble water with lasers of different angles and different wavelengths, and using a light intensity detector to capture the images and photon numbers of the optical paths generated in the nano-bubble water respectively, the photon numbers are converted into values of readable scattered light intensity. By assuming the diameter of nano-bubbles in the nano-bubble water and adjusting the nano-bubble diameter through the least squares algorithm until the theoretical scattered light intensity conforms to the set error with the obtained scattered light intensity. Using the adjusted nano-bubble diameter, the dimensionless size parameter is calculated, and a relational expression for detecting the scattered light intensity, nano-bubble water concentration and nano-bubble radius is constructed based on Mie scattering and Rayleigh scattering. However, when constructing a relationship model between the bubble radius and concentration in nano-bubble water based on Mie scattering, although it can be used to estimate the bubble size, its research object is the overall nano-bubble water system, and the large-volume scattering measurement method is adopted, which cannot focus on the behavior of a single bubble, does not involve the bubble generation process or detection path design under laser control, and is difficult to meet the time-sequence tracking and energy threshold determination of the dynamic evolution of nano-bubbles.

[0007] In summary, although the prior art has made certain explorations in aspects such as laser-controlled bubble generation, optical measurement and nanoparticle manipulation, there are still limitations. The prior art cannot achieve real-time, sensitive and all-optical measurement of key parameters such as the nucleation threshold, size change and lifetime evolution of a single nano-bubble under laser excitation in terms of measurement dimension, research object and system configuration. Therefore, it is of great significance to the research of nano-bubbles to propose a measurement method and system for multi-laser collaborative detection of nano-bubbles to achieve the above purposes. Summary of the Invention

[0008] In view of the above-mentioned defects of the prior art, in the first aspect of the present invention, there is provided a measurement method for multi-laser collaborative detection of nano-bubbles that can obtain key data in real time, has high measurement accuracy, realizes multi-angle measurement and wide applicability, including the following steps: (1) Prepare a suspension of gold nanoparticles; (2) Multi-laser collaborative detection: Using a pulsed laser as the excitation laser, focusing it into the suspension of gold nanoparticles, enabling the gold nanoparticles to locally absorb the laser energy and induce bubble generation, and controlling the nucleation threshold and growth behavior of the bubbles; Adopting an ultrashort pulsed detection laser (the first detection laser) with a wavelength different from that of the excitation laser, irradiating the bubble formation region in a lateral side illumination manner, and capturing the transient morphology of the bubbles at different time delays through time-resolved imaging to complete high-resolution imaging; Use a third continuous-wave laser with a different wavelength as the detection laser (the second detection laser) to monitor the local refractive index change during the bubble formation process based on the thermal lens effect; (3) Perform data collection and analysis.

[0009] Preferably, in the step (1), add gold nanoparticles to the dispersion medium to form a gold nanoparticle suspension; the particle size of the gold nanoparticles is 50 - 300 nm; the mass concentration of the gold nanoparticles is 1 - 100 μg / mL.

[0010] More preferably, the dispersion medium includes at least one of water and ethanol.

[0011] Mixing gold nanoparticles with a dispersion medium having good stability and dispersibility, such as water, ethanol, or their mixed solution, etc., can form a uniformly dispersed suspension. Controlling the gold nanoparticles within the preferred particle size range helps to ensure good photothermal conversion efficiency and bubble generation response characteristics. For the mass concentration of gold nanoparticles, too low a concentration may not effectively induce bubble generation, while too high a concentration may lead to particle aggregation, affecting bubble stability and measurement accuracy.

[0012] Preferably, in the step (2), a nanosecond (ns) or picosecond (ps) pulsed laser with a wavelength of 532 nm is used as the excitation laser; the pulse width of the nanosecond pulsed laser is 5 - 20 ns, and the pulse width of the picosecond pulsed laser is 10 - 100 ps; the power density of the pulsed laser is 400 - 1000 kW / cm 2 .

[0013] Preferably, in the step (2), the diameter of the bubbles is controlled within 10 - 500 nm, and the lifetime of the bubbles remains in the nanosecond to microsecond level.

[0014] The preferred pulsed laser can generate a plasmonic effect with the selected particles, and through lens focusing into the gold nanoparticle suspension, the nanoparticles locally absorb the laser energy and induce bubble generation. Adjusting the laser power density and pulse width can effectively control the nucleation threshold of the bubbles (i.e., the minimum laser energy required for the first detectable bubbles to appear) and the growth behavior of the bubbles (including the maximum size, lifetime, and extinction rate). To ensure measurement accuracy, the diameter of the nanobubbles is controlled within the preferred range by controlling the laser parameters, and the bubble lifetime remains in the nanosecond to microsecond level to ensure effective collection by the detection laser. The laser parameter setting needs to be carried out under the condition of avoiding a large amount of liquid vaporization or laser breakdown, ensuring that the formed bubbles are single, stable, and repeatable nucleated thermally induced bubbles, facilitating subsequent optical detection and size quantitative analysis.

[0015] Preferably, in the step (2), the wavelength of the ultrashort pulse probe laser is 600-800 nm; the ultrashort pulse probe laser is a femtosecond (fs) or picosecond (ps) ultrashort pulse light source. The pulse width of the femtosecond ultrashort pulse light source is 100-500 fs, and the pulse width of the picosecond ultrashort pulse light source is 1-10 ps; the repetition frequency of the ultrashort pulse probe laser is 1 kHz-10 MHz; the single pulse energy density of the ultrashort pulse probe laser is 0.1-0.5 J / cm 2 .

[0016] The selected wavelength of the ultrashort pulse probe laser is separated from the excitation laser so as to separate signals through the filter system. The femtosecond or picosecond ultrashort pulse light source is designed to improve the time resolution; the repetition frequency is controlled to synchronize imaging with the high-speed camera. The single pulse energy density is much lower than that of the excitation laser, aiming to ensure that no additional bubbles or perturbations are induced. Thus, through time-resolved imaging, using the ultrashort pulse probe light, the transient morphology (nucleation and collapse) of the bubbles is captured at different time delays, realizing high-resolution imaging.

[0017] Preferably, in the step (2), the wavelength of the continuous wave laser is 750-850 nm; the power of the continuous wave laser is 1-50 mW.

[0018] Preferably, in the step (2), the transmission irradiation mode is adopted to continuously monitor the change of the light intensity of the continuous wave laser in the medium around the bubble; combined with a high-sensitivity photodetector to record the weak fluctuation of the detected light intensity over time, and quantitatively analyze the existence time and dynamic behavior of the bubble.

[0019] In this step, a third continuous light source with a different wavelength is used as the probe laser to monitor the local refractive index change during the bubble formation process based on the thermal lens effect. This laser beam is dedicated to capturing the evolution of the liquid refractive index field caused by temperature changes, thereby reflecting the growth life and dynamic behavior of the nanobubbles. Within the preferred wavelength range, there is an obvious wavelength difference from the excitation laser and the pulsed probe laser, which is convenient for signal filtering and separation. And the power is controlled to avoid causing excitation or bubble perturbation. Using the transmission irradiation (transmission type or lateral passing through the sample) mode, continuously monitor the change of the light intensity of the laser in the medium around the bubble; combined with a high-sensitivity photodetector (such as PD, APD, etc.) to record the weak fluctuation of the detected light intensity over time, and then quantitatively analyze the existence time and dynamic behavior of the bubble. Different from another pulsed probe laser, this continuous probe light is used for integral signal monitoring to realize the optical response recording of the refractive index change during the whole process of the bubble existence, which is suitable for supplementing the process that is difficult to capture for a long time by time-resolved imaging means, and further improving the resolution ability of the system for the bubble life and microscale dynamic changes.

[0020] Preferably, in step (3), in combination with the acquisition device, the growth process, size change and kinetic characteristics of the bubbles are recorded in real time; by adjusting the parameter variables, the formation mechanism of the nanobubbles and their stability in different environments are analyzed.

[0021] In actual operation, in combination with a high-speed CCD camera, a photodetector and a high-speed data acquisition device, the growth process, size change and kinetic characteristics of the bubbles can be recorded in real time. By adjusting variables such as laser parameters and particle concentration, the formation mechanism of the nanobubbles and their stability in different environments are analyzed.

[0022] In a second aspect of the present invention, there is provided a system for the measurement method of multi-laser cooperative detection of nanobubbles according to the first aspect of the present invention, including: A single-pulse excitation laser, the excitation laser emitted by which is focused into the gold nanoparticle suspension via a first reflector and a beam expander, so that the gold nanoparticles locally absorb the laser energy and induce the generation of bubbles; A pulsed detection laser for emitting an ultrashort pulsed detection laser to laterally illuminate the bubble formation region; A continuous detection laser for emitting a continuous wave laser; The detection information is transmitted by a lens to a CCD camera via a second reflector for time-resolved imaging; and is transmitted to a high-speed photodetector via a third reflector for measuring the thermal lens effect.

[0023] Based on the above technical solutions, the design concept and principle of the present invention are as follows: In the present invention, through a three-laser cooperative system, one laser is used to excite gold nanoparticles to induce bubble formation, and the other two lasers are used to detect the bubble size and kinetic characteristics. Combining time-resolved imaging and the thermal lens effect to complete high-precision measurement, the organic integration of bubble generation control and high-resolution detection is realized for the first time.

[0024] The real-time measurement of the three-laser system breaks through the limitations of a single measurement method: one laser is used to precisely control the generation of nanobubbles, and at the same time, two detection lasers are used to measure by time-resolved imaging and the thermal lens effect respectively. The size, kinetic evolution and formation threshold of the bubbles can be obtained simultaneously, realizing synchronous measurement with high time resolution and spatial resolution. Compared with a single-laser or dual-laser system, the present invention provides more complete bubble kinetic information, ensuring measurement accuracy and data reliability.

[0025] High-sensitivity detection at the nanoscale: Combining Mie scattering or optical interference technology can effectively enhance the signal of nanobubbles and improve the detection sensitivity. Traditional optical microscopes are limited by the diffraction limit, while this system can accurately measure the size change of nanoscale bubbles through coherent light detection and scattering signal analysis, achieving higher precision than optical imaging.

[0026] Measurement of adjustable bubble generation threshold: By precisely controlling the energy density and pulse width of the excitation laser, the nucleation threshold of bubbles induced by gold nanoparticles can be measured, providing optimized parameters for applications such as laser processing, biomedicine, and micro- and nano-scale fluid control. Combining the detection beam feedback enables real-time adjustment of laser parameters, improving the controllability of bubble generation and further expanding its applications in fields such as photothermal therapy and micro- and nano-fabrication.

[0027] Compared with the prior art, the present invention has the following advantages and beneficial effects: The present invention provides a measurement method for multi-laser collaborative detection of nano-bubbles. Through an excitation-detection dual-laser system, key data such as the size, lifetime, and formation threshold of nano-bubbles can be obtained in real time, breaking through the limitation of the resolution of traditional optical microscopy imaging and improving the measurement accuracy. This method combines time-resolved imaging and thermal lens measurement to achieve comprehensive bubble monitoring. By using time-resolved imaging technology, information such as the nucleation and collapse changes of nano-bubbles can be obtained. Combining with thermal lens effect measurement, the maximum diameter, lifetime of bubbles, and their response to environmental changes are analyzed to achieve multi-angle measurement. Precise control of nano-bubble generation optimizes laser processing and biological applications. By adjusting parameters such as laser pulse energy, spot size, and particle concentration, the controllable generation of nano-bubbles is optimized, which is applicable to applications such as laser micromachining, microfluidic manipulation, and biological labeling. And this method is a non-contact optical measurement, without electrodes or other external interventions, applicable to various scenarios such as liquid phase environment, biological tissue, and micro- and nano-scale material surfaces, improving the applicability.

[0028] The present invention provides a system for a measurement method of multi-laser collaborative detection of nano-bubbles. Through the innovative design of the laser system, high-precision time-resolved measurement and thermal lens detection technology are realized, providing technical support for the research on micro- and nano-scale phase change dynamics and its application expansion. Description of the Drawings

[0029] Figure 1 It is a schematic diagram of the structure and optical path of a system for a measurement method of multi-laser collaborative detection of nano-bubbles; In the figure, 1: single-pulse excitation laser; 2: pulsed detection laser; 3: CCD camera; 4: high-speed photodetector; 5: first mirror; 6: magnifying lens; 7: gold nanoparticle suspension; 8: continuous detection laser; 9: lens; 10: second mirror; 11: third mirror; Figure 2 It is a process flow chart of a measurement method for multi-laser collaborative detection of nano-bubbles; Figure 3 It is a schematic diagram of the principle of detecting nano-bubbles by time-resolved imaging of the detection laser and thermal lens effect measurement. Detailed Embodiments

[0030] The present invention will be further described below by way of examples, but the present invention is not limited to the scope of the described examples. For the experimental methods without specific conditions indicated in the following examples, conventional methods and conditions are followed, or selected according to the product specifications.

[0031] Example 1 This example provides a system for the measurement method of multi-laser collaborative detection of nanobubbles, Figure 1 showing its mechanism and optical path layout. When in use, three lasers work together. The excitation laser is used to irradiate gold nanoparticles, causing its local temperature to rise rapidly, inducing the nucleation and growth of nanobubbles. The first detection laser uses time-resolved imaging technology to obtain the nucleation and collapse processes of nanobubbles. The second detection laser is used for thermo-lens effect measurement to characterize the lifetime and size changes of nanobubbles. In the experimental setup, the excitation laser is focused by a lens onto the gold nanoparticle suspension in the liquid phase, locally generating a surface plasmon resonance effect, triggering the formation of nanobubbles. The generation of bubbles causes changes in the optical properties of the medium. At this time, the two detection lasers are incident transversely respectively to achieve dynamic measurement of the nanobubble size.

[0032] Example 2 The measurement method of multi-laser collaborative detection of nanobubbles, the process flow is as Figure 2 shown, and the steps are as follows: (1) Prepare the gold nanoparticle suspension: Select a dispersion medium with good stability and dispersibility (water, ethanol or their mixed solution is acceptable), and add gold nanoparticles into it to prepare a uniformly dispersed gold nanoparticle suspension; the particle size of the gold nanoparticles is controlled within 50 - 300 nm to ensure good photothermal conversion efficiency and bubble generation response characteristics; the mass concentration of the gold nanoparticle solution is controlled at 1 - 100 μg / mL to prevent agglomeration while effectively inducing bubble generation, ensuring bubble stability and measurement accuracy; (2) Multi-laser collaborative detection: Use a pulsed laser (532 nm) to irradiate the gold nanoparticles, which is focused by a lens into the gold nanoparticle suspension to trigger bubble nucleation, and control parameters such as laser power and pulse width to achieve controllable generation of nanobubbles; Simultaneously detect the nanobubble size and kinetic evolution. The first detection laser (690 nm) is used for time-resolved imaging to capture the formation and disappearance processes of bubbles, and record the images with a high-speed camera; the second detection laser (808 nm) is based on thermo-lens effect measurement. When bubbles are formed, the local refractive index changes, and the transmission characteristics of the detection beam are modulated. Use a photodetector to record the change of the transmitted light signal to measure the lifetime and kinetic characteristics of the bubbles; (3) Data analysis and feedback: By performing real-time analysis on the detection signals, the size, lifespan, and kinetic parameters of the nanobubbles are extracted, providing data support for optimizing laser processing, biomedical applications, etc.

[0033] Those skilled in the art can make adjustments within the preferred parameters of the present invention to complete the above measurements according to actual test requirements.

[0034] Figure 3 The principle of measuring nanobubbles by time-resolved imaging of the detection laser and the thermal lens effect is shown.

[0035] Time-resolved imaging technique: This method utilizes the linkage between the detection beam and a high-speed camera. Through time-resolved optical scattering imaging, it realizes the precise capture of the nucleation and collapse processes of nanobubbles. The high-speed camera can record the changes in the light scattering signal with extremely high time resolution, thereby reconstructing the dynamic behavior of the nanobubbles.

[0036] Measurement of the thermal lens effect: When a nanobubble is formed, the local temperature change induces a spatial gradient distribution of the refractive index of the liquid, causing a change in the transmittance or deflection of the detection beam during propagation, forming the thermal lens effect. This change directly affects the light intensity distribution and phase characteristics of the detection light. By continuously irradiating the sample with a laser and precisely measuring the time evolution of the detection light intensity using a photodetector (such as a photodiode or a CCD sensor), the integral optical scattering signal of the bubble can be obtained. Combining with the signal attenuation characteristics, the size, lifespan, and their interaction with the environment of the nanobubbles can be quantitatively analyzed.

[0037] In summary, the present invention provides an efficient and controllable method for measuring nanobubbles, providing important technical support for research and applications in fields such as micro-nano manufacturing, thermal management, and biomedicine. Compared with single-laser and dual-laser systems, the triple-laser system of the present invention has significant advantages in terms of measurement accuracy, anti-interference ability, and applicable range. The single-laser system is prone to interference and has limited measurement parameters because the excitation and detection share the same light source. Although the dual-laser system can partially reduce interference and measure the bubble size and kinetic characteristics, it is still difficult to comprehensively characterize the thermal effect and refractive index change of the bubbles. The triple-laser system precisely excites the bubbles with one laser beam and uses two detection laser beams to perform time-resolved imaging and thermal lens effect measurement respectively, realizing synchronous monitoring of multiple parameters such as bubble size, lifespan, and refractive index change, improving the measurement stability and sensitivity, being suitable for the research of smaller-sized nanobubbles and high-precision detection requirements, and providing stronger technical support for fields such as micro-nano manufacturing, thermal management, and biomedicine.

[0038] The preferred specific embodiments of the present invention have been described in detail above. It should be understood that those of ordinary skill in the art can make many modifications and variations based on the concept of the present invention without creative efforts. Therefore, all technical solutions that can be obtained by those skilled in the art in this technical field based on the concept of the present invention through logical analysis, reasoning, or limited experiments on the basis of the prior art should fall within the protection scope determined by the claims.

Claims

1. A measurement method for co-detecting nanobubbles by multiple lasers, characterized in that, It includes the following steps: (1) Prepare a suspension of gold nanoparticles; (2) Multi-laser collaborative detection: Use pulsed laser as the excitation laser, focus it into the suspension of gold nanoparticles, so that the gold nanoparticles locally absorb the laser energy and induce the generation of bubbles, and control the nucleation threshold and growth behavior of the bubbles; Use an ultrashort pulsed probe laser with a wavelength different from that of the excitation laser, irradiate the bubble formation region in a lateral side illumination manner, and capture the transient morphology of the bubbles at different time delays through time-resolved imaging to complete high-resolution imaging; Use a third continuous wave laser with a different wavelength as the probe laser to monitor the local refractive index change during the bubble formation process based on the thermal lens effect; (3) Perform data acquisition and analysis.

2. The measurement method for co-detecting nanobubbles with multiple lasers according to claim 1, characterized in that: In the step (1), add gold nanoparticles to the dispersion medium to form a suspension of gold nanoparticles; the particle size of the gold nanoparticles is 50 - 300 nm; the mass concentration of the gold nanoparticles is 1 - 100 μg / mL.

3. The measurement method for detecting nano-bubbles by multi-laser collaboration according to claim 2, wherein: The dispersion medium includes at least one of water and ethanol.

4. The measurement method for co-detecting nanobubbles by multiple lasers according to claim 1, wherein: In the step (2), a nanosecond or picosecond pulsed laser with a wavelength of 532 nm is used as the excitation laser; the pulse width of the nanosecond pulsed laser is 5 - 20 ns, and the pulse width of the picosecond pulsed laser is 10 - 100 ps; the power density of the pulsed laser is 400 - 1000 kW / cm 2 .

5. The measurement method for detecting nano-bubbles by multi-laser cooperation according to claim 1, characterized in that: In the step (2), the diameter of the bubbles is controlled to be 10 - 500 nm, and the lifetime of the bubbles is maintained at the nanosecond to microsecond level.

6. The measurement method for co-detecting nano-bubbles by multiple lasers according to claim 1, wherein: In the step (2), the wavelength of the ultrashort pulsed probe laser is 600 - 800 nm; the ultrashort pulsed probe laser is a femtosecond or picosecond ultrashort pulsed light source, the pulse width of the femtosecond ultrashort pulsed light source is 100 - 500 fs, and the pulse width of the picosecond ultrashort pulsed light source is 1 - 10 ps; The repetition frequency of the ultrashort pulse probing laser is 1 kHz to 10 MHz; the single-pulse energy density of the ultrashort pulse probing laser is 0.1 to 0.5 J / cm 2 .

7. The measurement method for detecting nanobubbles through multi-laser collaboration according to claim 1, wherein: In the step (2), the wavelength of the continuous wave laser is 750 - 850 nm; the power of the continuous wave laser is 1 - 50 mW.

8. The measurement method for co-detecting nanobubbles with multiple lasers according to claim 1, wherein: In the step (2), adopt a penetration irradiation method to continuously monitor the light intensity change of the continuous wave laser in the medium around the bubbles; combine a high-sensitivity photodetector to record the weak fluctuation of the detected light intensity over time, and quantitatively analyze the existence time and dynamic behavior of the bubbles.

9. The measurement method for detecting nanobubbles by multi-laser cooperation according to claim 1, wherein: In the step (3), combine the acquisition device to record the growth process, size change and dynamic characteristics of the bubbles in real time; by adjusting the parameter variables, analyze the formation mechanism of the nanobubbles and their stability in different environments.

10. A system for a measurement method of multi-laser collaborative detection of nano-bubbles as described in any one of claims 1 to 9, characterized in that, It includes: A single-pulse excitation laser (1), the excitation laser emitted by which is focused into the suspension of gold nanoparticles (7) via a first reflector (5) and a beam expander (6), so that the gold nanoparticles locally absorb the laser energy and induce the generation of bubbles; A pulsed probe laser (2) for emitting an ultrashort pulsed probe laser to laterally illuminate the bubble formation region; A continuous probe laser (8) for emitting a continuous wave laser; The detection information is transmitted by a lens (9) to a CCD camera (3) via a second reflector (10) for time-resolved imaging; and is transmitted to a high-speed photodetector (4) via a third reflector (11) for thermal lens effect measurement.

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