A method for measuring aerodynamic aberration based on high frame rate and high spatial resolution Hartmann

Abstract

The present invention discloses a method for measuring aerodynamic aberration based on a high-frame-rate and high-spatial-resolution Hartmann sensor. Short-exposure and high-frame-rate acquisition of aerodynamic aberration is achieved through a pulsed laser and a photodetector with a high acquisition frequency. Detection of aberration at the micron scale is realized by using a micro-lens array with high spatial resolution. The light beam emitted from the measurement light source passes through the aerodynamic flow field in the wind tunnel and then enters the wavefront sensor. After the aperture transformation and aberration transfer by the beam reduction module, the aerodynamic aberration is spatially divided by the micro-lens array to form a dot matrix with a spatial offset relative to the ideal position. The dot matrix of the micro-lens array is imaged onto the photodetector through a magnification matching system. The present invention is more conducive to realizing quantitative measurements of parameters such as the refractive index of the aerodynamic flow field medium and aerodynamic aberration, can be used to measure the gas density distribution in the wind tunnel flow field, can provide design input parameters for the aerodynamic aberration correction system of the flow field, and can also be used for detecting the distorted wavefront of the aerodynamic aberration correction system.

Description

Technical Field

[0001] The present invention belongs to the field of pneumatic aberration measurement, and particularly relates to a pneumatic aberration measurement method based on a high-frame-rate and high-spatial-resolution Hartmann, which is for measuring the pneumatic optical effect of a flow field based on a high-frame-rate and high-spatial-resolution wavefront sensor. It can be used to measure the gas density distribution in a wind tunnel flow field, provide design input parameters for a flow field pneumatic aberration correction system, and can also be used for detecting the distorted wavefront of a pneumatic aberration correction system. Background Art

[0002] When a high-speed aircraft flies in the atmosphere, a complex flow field will be formed. The refractive index of the medium in the flow field is highly non-uniform and there are high-frequency pulsations. When light waves propagate in it, phenomena such as wavefront distortion, beam jitter, and direction deflection will occur, which is called the pneumatic optical effect. This effect causes the images collected by optical instruments inside the aircraft to be distorted, blurred, and the image quality to degrade. In order to study the influence of the pneumatic optical effect on target imaging and laser transmission, it is necessary to measure the pneumatic optical aberration in a high-speed flow field at spatio-temporal resolution. On the one hand, it can be used for quantitative analysis of the density field distribution in the flow field, facilitating the optimization design of the aircraft window. On the other hand, it can provide data input for analyzing the spatio-temporal characteristics of pneumatic aberration and also provide parameter constraints for pneumatic aberration correction.

[0003] At present, the background-oriented schlieren (BOS) wavefront sensing method is mostly used to measure the pneumatic optical aberration. This method is a new experimental means for measuring the two-dimensional distribution of the optical wavefront using the background schlieren technique. However, the obtained density field is greatly affected by the integration effect in the light direction, and there are problems such as low spatio-temporal resolution, environmental sensitivity, and overall effect, making it difficult to quantitatively analyze the spatio-temporal frequency characteristics of pneumatic aberration and the local small-scale gas density changes.

[0004] The Shack-Hartmann wavefront sensor (SH-WFS) has the advantages of simple and compact structure and high light energy utilization rate, and has been successfully applied in fields such as high-precision wavefront detection and adaptive optical correction. This sensor mainly consists of a microlens array and a photoelectric sensor. When there is a wavefront distortion in the incident wavefront, the centroid position of the focused sub-spot corresponding to the microlens shifts. By measuring the shift amount of the centroid position of the focused sub-spot relative to the calibrated position, the wavefront slope corresponding to the sub-aperture can be obtained. After knowing the incident wavefront slope data, the phase distribution of the incident wavefront can be obtained through a wavefront reconstruction algorithm. Because of its compact structure and no reference beam, it also has good measurement accuracy and stability in a vibrating environment and is suitable for measuring pneumatic aberration in a high-speed flow field. However, its spatial resolution is limited by the sub-aperture segmentation density and the microlens size, and high-spatial-resolution research still needs to be carried out.

[0005] Facing the high-precision measurement requirements of aerodynamic aberration in the disturbed flow field of high-speed aircraft, in order to achieve the measurement of aerodynamic aberration with spatial scales ranging from dozens of micrometers to several millimeters and temporal pulsation frequencies ranging from hundreds of hertz to thousands of hertz in a high-speed complex flow field, it is necessary to carry out research on new wavefront detection methods. Summary of the Invention

[0006] The object of the present invention is to solve the problem that it is difficult for existing aerodynamic aberration measurement methods to quantitatively measure the spatio-temporal frequency characteristics and local large-undulation aberrations of aerodynamic aberration at high spatio-temporal resolutions. By analyzing the optical characteristics and fluid characteristics of the aerodynamic flow field, an aerodynamic aberration measurement device is constructed. A wind tunnel is used to simulate the complex flow field, and a high-frame-rate and high-spatial-resolution Shack-Hartmann wavefront sensor is constructed to achieve the measurement of aerodynamic aberration.

[0007] The technical solution adopted by the present invention is as follows: An aerodynamic aberration measurement method based on a high-frame-rate and high-spatial-resolution Hartmann includes a pulsed laser 1, a laser collimation module 2, an off-axis parabolic primary mirror 3, a focal length adjustment device 4, a collimating mirror 5, a stray light suppression module 6, an attenuation filter module 7, a microlens array 8, a magnification matching system 9, a photodetector 10, and a synchronous trigger device 11. The pulsed laser 1 and the laser collimation module 2 form a measurement light source, and the off-axis parabolic primary mirror 3, the focal length adjustment device 4, the collimating mirror 5, the stray light suppression module 6, the attenuation filter module 7, the microlens array 8, the magnification matching system 9, the photodetector 10, and the synchronous trigger device 11 form a wavefront sensor. The measurement light source and the wavefront sensor are respectively arranged on both sides of the wind tunnel measurement window. The off-axis parabolic primary mirror 3, the focal length adjustment device 4, and the collimating mirror 5 constitute an off-axis beam reduction system. The beam emitted by the measurement light source passes through the aerodynamic flow field in the wind tunnel and then enters the wavefront sensor. After the aperture transformation and aberration transfer of the beam reduction module, the aerodynamic aberration is spatially segmented by the microlens array to form a dot matrix with a spatial offset relative to the ideal position. The dot matrix of the microlens array is imaged onto the photodetector 10 through the magnification matching system. The specific implementation steps are as follows:

[0008] Step 1: Turn on the pulsed laser 1. The emitted light beam passes through the laser collimation module 2 to obtain the measurement light source emitted light beam. The measurement light source emitted light beam passes through the pneumatic flow field in the wind tunnel device and then enters the main beam reduction module of the wavefront sensor. Adjust the off-axis parabolic mirror 3 and the collimating mirror 5 so that their optical axes coincide and the distance between their vertices is less than the sum of their focal lengths. After adjustment, fix the positions of the off-axis parabolic mirror 3 and the collimating mirror 5. Then place the focal length adjustment device 4 in the optical path between the off-axis parabolic mirror 3 and the collimating mirror 5, and adjust to make the optical axis of the focal length adjustment device coincide with the optical axes of the off-axis parabolic mirror 3 and the collimating mirror 5. The emitted light beam passes through the off-axis beam reduction system to complete the reduction of the incident light beam aperture and is emitted to the stray light suppression module 6, and then passes through the attenuation filter module 7 and is emitted to the microlens array 8. The pneumatic aberration is spatially divided by the microlens array to form a dot matrix with a spatial offset relative to the ideal position. The magnification matching system 9 images the distorted wavefront sub-spot dot matrix image formed by the microlens array 8 onto the photodetector 10. The photodetector 10 is connected to the synchronous trigger device 11 at the back to achieve synchronous acquisition of the light source and the pneumatic aberration of the photodetector 10;

[0009] Step 2: Extract the sub-spot image on the photodetector 10, calculate the offset of the sub-spot relative to the calibration position through the spot positioning technology, and calculate the wavefront slope using the sub-spot offset;

[0010] Step 3: Restore the wavefront of the incident light beam through the wavefront restoration algorithm. The high-frame-rate and high-spatial-resolution Hartmann wavefront sensor uses the mode method to restore the wavefront. According to the sub-aperture segmentation layout and the set Zernike aberration mode, construct a restoration matrix for calculating the aberration mode coefficients based on the centroid offset or slope data of the spots within the sub-apertures.

[0011] Further, the measurement light source described in Step 1 is a high-repetition-rate and narrow-pulse-width laser to achieve the acquisition of pneumatic aberration under extremely short exposure.

[0012] Further, the main beam reduction module of the wavefront sensor described in Step 1 can be an off-axis beam reduction system composed of an off-axis parabolic mirror, a focal length adjustment device, and a collimating mirror, or any optical system that can achieve beam aperture transformation.

[0013] Further, the synchronous trigger device 11 described in Step 1 is connected to the light source and the photodetector 10. When measuring the pneumatic aberration, the synchronous trigger device 11 sends a synchronous trigger signal to the pulsed laser 1 and the photodetector 10 according to a preset frequency. After receiving the trigger signal, the pulsed laser 1 emits a laser pulse, and the photodetector 10 starts to collect images.

[0014] Further, the magnification matching system 9 described in Step 1 images the distorted wavefront sub-spot dot matrix image formed by the microlens array 8 onto the photodetector 10, and its magnification is a fixed imaging magnification, or it can also be an imaging magnification variable system.

[0015] Further, when the main beam shrinking module and the magnification matching system 9 described in step 1 are of variable magnification, by adjusting the magnification of the main beam shrinking module and the magnification of the magnification matching system 9, it is possible to achieve variable spatial resolution and variable sampling frequency pneumatic aberration detection without changing the structure of the measurement system.

[0016] Further, the spot positioning technique described in step 2 includes the weighted centroid method, the threshold centroid method, the matched filtering method, the registration algorithm, or any other method that can locate the spot position.

[0017] Further, the wavefront reconstruction algorithm described in step 3 includes the modal method and the zonal method, which are methods that can achieve wavefront reconstruction from the sub-aperture spot array data of the Hartmann sensor.

[0018] The principle of the present invention lies in: a method for measuring aerodynamic aberration based on a high-frame-rate and high-spatial-resolution Hartmann sensor, which mainly realizes short-exposure and high-frame-rate acquisition of aerodynamic aberration through a pulsed laser and a photodetector with a high acquisition frequency, and uses a micro-lens array with high spatial resolution to detect aberrations at the micron level. The device includes: a pulsed laser, a laser collimation module, a main beam reduction module, a stray light suppression module, an attenuation filter module, a micro-lens array, a magnification matching system, a photodetector, and a synchronous trigger device. Among them, the pulsed laser and the laser collimation module form the measurement light source, and the remaining components form the wavefront sensor. The measurement light source and the wavefront sensor are respectively arranged on both sides of the measurement window of the wind tunnel. When measuring aerodynamic aberration, the beam emitted by the measurement light source passes through the aerodynamic flow field in the wind tunnel and then enters the wavefront sensor. After the aperture transformation and aberration transfer by the beam reduction module, the aerodynamic aberration is spatially divided by the micro-lens array to form a dot matrix with a spatial offset relative to the ideal position. The dot matrix of the micro-lens array is imaged onto the photodetector through the magnification matching system. The main beam reduction module of the wavefront sensor can be an off-axis beam reduction system composed of an off-axis parabolic mirror, a focal length adjustment device, and a collimating mirror, or any optical system that can achieve beam aperture transformation. The main function of the main beam reduction module is to reduce the aperture of the incident beam and map the aerodynamic aberration carried by the incident beam onto the micro-lens array through the optical matching relationship. The beam reduction ratio of the main beam reduction module can be a fixed ratio or a variable ratio. In order to achieve acquisition under extremely short exposure of aerodynamic aberration, the laser light source is a high-repetition-rate and narrow-pulse-width laser. The light source and the photodetector use the synchronous trigger device to achieve synchronous acquisition of aerodynamic aberration. When measuring aerodynamic aberration, the synchronous trigger device sends a synchronous trigger signal to the laser light source and the photodetector according to a preset frequency. After receiving the trigger signal, the pulsed laser emits a laser pulse, and the photodetector starts to acquire images. The magnification matching system images the distorted wavefront sub-spot matrix image formed by the micro-lens array onto the photodetector, and its magnification can be a fixed imaging magnification or a variable imaging magnification system. When the main beam reduction module and the magnification matching system have variable magnifications, by adjusting the magnifications of the main beam reduction module and the magnification matching system, it is possible to achieve aerodynamic aberration detection with variable spatial resolution and variable sampling frequency without changing the structure of the measurement system. After completing the acquisition of aerodynamic aberration using the Hartmann wavefront sensor, using the distorted wavefront dot matrix data produced by the micro-lens array, the aerodynamic aberration is restored through processes such as centroid offset calculation and wavefront reconstruction. The wavefront reconstruction algorithms include the modal method, the zonal method, etc., which are methods that can achieve wavefront reconstruction from the sub-spot matrix data of the Hartmann sensor.

[0019] The present invention has the following advantages compared with the prior art:

[0020] (1) The present invention uses a high-frame-rate and high-spatial-resolution Hartmann wavefront sensor to achieve pneumatic aberration measurement. By optimizing the system structure design, high-time-resolution and high-spatial-resolution acquisition of pneumatic aberration can be realized under extremely short exposure. Compared with existing general pneumatic aberration measurement methods, it is easier to achieve quantitative measurement of the refractive index of the pneumatic flow field medium, pneumatic aberration, etc.

[0021] (2) Compared with pneumatic aberration measurement technologies such as interferometers, the structure of the present invention does not require a reference beam and has the advantage of a compact structure, making it suitable for pneumatic aberration measurement in a wind tunnel environment, especially under vibration.

[0022] (3) When the main beam reduction module and the magnification matching system of the device of the present invention have variable magnifications, by adjusting the magnifications of the main beam reduction module and the magnification matching system, pneumatic aberration detection with variable spatial resolution and variable sampling frequency can be achieved without changing the structure of the measurement system, which has the advantage of a flexible structure. Description of the Drawings

[0023] Figure 1 is an experimental device diagram of a pneumatic aberration measurement method based on a high-frame-rate and high-spatial-resolution Hartmann of the present invention. Among them, 1 is a pulsed laser, 2 is a laser collimation module, 3 is an off-axis parabolic primary mirror, 4 is a focal length adjustment device, 5 is a collimating mirror, 6 is a stray light suppression module, 7 is an attenuation filter module, 8 is a microlens array, 9 is a magnification matching system, 10 is a photodetector, and 11 is a synchronous trigger device;

[0024] Figure 2 is a synchronous trigger system for a pulsed laser and a photodetector;

[0025] Figure 3 is the synchronous working timing of a pulsed laser and a photodetector system;

[0026] Figure 4 is a schematic diagram corresponding to different sub-aperture array numbers when the main beam reduction module and the magnification matching system have variable magnifications;

[0027] Figure 5 is a diagram for extracting the position of sub-spots of a high-speed detector;

[0028] Figure 6 is a wavefront reconstruction diagram of a high-speed detector at a frame rate of 46. Detailed Embodiment

[0029] To make the working principle and implementation process of the device of the present invention clearer, the present invention is further described below in conjunction with the drawings and specific embodiments.

[0030] As Figure 1As shown in the figure, a method for measuring aerodynamic aberration based on a high frame rate and high spatial resolution Hartmann uses a measuring device. The measuring device is composed of a pulsed laser 1, a laser collimation module 2, an off-axis parabolic primary mirror 3, a focal length adjustment device 4, a collimating mirror 5, a stray light suppression module 6, an attenuation filter module 7, a microlens array 8, a magnification matching system 9, a photodetector 10, a synchronous trigger device 11, etc. The pulsed laser 1 and the laser collimation module 2 form a measuring light source, and the remaining devices form a wavefront sensor. The measuring light source and the wavefront sensor are respectively arranged on both sides of the wind tunnel measurement window. Among them, the off-axis parabolic primary mirror 3, the focal length adjustment device 4, and the collimating mirror 5 constitute an off-axis beam reduction system. It is necessary to adjust the combined focal length of the off-axis beam reduction system. First, after adjusting the optical axes of the off-axis parabolic primary mirror 3 and the collimating mirror 5 to coincide, fix their positions. Place the focal length adjustment device 4 in the optical path between the off-axis parabolic primary mirror 3 and the collimating mirror 5, and adjust the optical axis of the focal length adjustment device to coincide with the optical axes of the off-axis parabolic primary mirror 3 and the collimating mirror 5. Secondly, introduce the beam emitted by the light source into the off-axis beam reduction system through the aperture stop, and then exit from the exit pupil. Place a shear plate behind the exit pupil, and the light reflected by the shear plate is projected onto the observation surface. Finally, use the focal length adjustment device to adjust the combined focal length of the off-axis parabolic primary mirror 3 and the collimating mirror 5 so that the interference fringes presented on the observation surface are distributed in a specific form, completing the adjustment of the combined focal length. The measuring light source and the photodetector use the synchronous trigger device 11 to achieve synchronous acquisition of aerodynamic aberration, and its working system is as Figure 2 .

[0031] In the embodiment of the present invention, taking the MEMRECAM ACS-1M60 photodetector of Weice Company as an example, the laser wavelength is 532 nm, the number of microlens arrays is 128×128 (Ф20 mm), the sub-aperture size is 150 μm×150 μm, the focal length of the microlens is 9.25 mm, the number of pixels covered by the sub-aperture is 6×6, the beam reduction ratio of the main beam reduction module is ×-0.2, and the matching ratio of the magnification matching system is ×0.2. The size of the sub-aperture of the photodetector is 90 μm, the spatial resolution is 750 μm, and the sampling frequency is 50~25000 Hz.

[0032] The specific implementation steps are as follows:

[0033] Step 1: Turn on the pulsed laser 1. The light source and the photodetector use the synchronous trigger device 11 to achieve synchronous acquisition of aerodynamic aberration. The emitted beam passes through the laser collimation module to obtain the emitted beam of the measurement light source. The emitted beam of the measurement light source is incident on the off-axis beam reduction system after passing through the aerodynamic flow field in the wind tunnel device. Adjust the off-axis parabolic primary mirror 3 and the collimating mirror 5 so that their optical axes coincide and the distance between their vertices is less than the sum of their focal lengths. After adjustment, fix the positions of the off-axis parabolic primary mirror 3 and the collimating mirror 5. Then place the focal length adjustment device 4 in the optical path between the off-axis parabolic primary mirror 3 and the collimating mirror 5, and adjust to make the optical axis of the focal length adjustment device coincide with the optical axes of the off-axis parabolic primary mirror 3 and the collimating mirror 5. The emitted beam passes through the off-axis beam reduction system to complete the reduction of the incident beam aperture and is emitted to the stray light suppression module 6, and then passes through the attenuation filter module 7 and is emitted to the microlens array 8. The aerodynamic aberration is spatially divided by the microlens array 8 to form a dot matrix with a spatial offset relative to the ideal position. The magnification matching system 9 images the distorted wavefront sub-spot dot matrix image formed by the microlens array 8 onto the photodetector 10. The photodetector 10 is connected to the synchronous trigger device 11 behind it to achieve synchronous acquisition of aerodynamic aberration of the light source and the photodetector 10.

[0034] When measuring the aerodynamic aberration, the synchronous trigger device 11 sends a synchronous trigger signal to the pulsed laser 1 and the photodetector 10 at a preset frequency as Figure 3 shown. After receiving the trigger signal, the pulsed laser emits laser pulses. After the photodetector 10 recognizes the falling edge, it starts to turn on the electronic shutter pulse, and the exposure time starts. After the photodetector 10 recognizes the rising edge, it starts the charge transfer work, the exposure ends, and at the same time, it outputs an image signal to the acquisition card.

[0035] When the main beam reduction module and the magnification matching system have variable magnifications, by adjusting the magnification parameters of the main beam reduction module and the magnification matching system, the schematic diagrams corresponding to different sub-aperture array numbers can be obtained without changing the structure of the measurement system as Figure 4 shown, and aerodynamic aberration detection with variable spatial resolution and variable sampling frequency can be achieved.

[0036] Step 2: After the image acquisition is completed, extract the sub-spot image on the photodetector as Figure 5 shown, calculate the offset of the sub-spot relative to the calibrated position, and use the sub-spot offset to calculate the wavefront slope.

[0037] The complex amplitude u(x f , y f ) of the light field on the focal plane of the i-th sub-aperture is:

[0038]

[0039] Among them, \(u(x_0,y_0)\) is the complex amplitude of the incident light wave, \(\lambda\) is the laser wavelength, \(f\) is the focal length of the microlens, and the wave number \(k = 2\pi / \lambda\).

[0040] The centroid position of the focused spot in the x-direction is:

[0041]

[0042] Among them, \(x\) c is the centroid position of the focused spot in the x-direction, \(u\) * (x,y) is the conjugate of \(u(x,y)\), and Re is to take the real part of the complex number.

[0043] The centroid position of the focused spot in the y-direction is:

[0044]

[0045] Among them, \(y\) c is the centroid position of the focused spot in the y-direction, \(u\) * (x,y) is the conjugate of \(u(x,y)\), and Re is to take the real part of the complex number.

[0046] The wavefront slopes of the incident wavefront in the x and y directions:

[0047]

[0048]

[0049] Among them, is the wavefront slope of the incident wavefront in the x and y directions, represents the centroid position of the focused spot of the incident light wave of the (i,j)th sub-aperture, and represent the centroid position of the focused spot of the calibration light wave.

[0050] Step 3: Finally, restore the wavefront of the incident beam through the wavefront restoration algorithm. Select the frame rate of the photodetector as 46 as Figure 6 shown. In the embodiment, the Hartmann wavefront sensor uses the mode method to restore the wavefront. According to the sub-aperture segmentation arrangement and the set Zernike aberration mode, a restoration matrix for calculating the aberration mode coefficients can be constructed based on the centroid offset or slope data of the spots within the sub-apertures by the classical mode method. This matrix can be generated in advance as the system configuration.

[0051] As described above, it is only the specific implementation manner in the present invention, but the protection scope of the present invention is not limited thereto. Any transformation or replacement that can be understood and conceived by those familiar with the technology within the technical scope disclosed by the present invention should be covered within the scope of the present invention.

Claims

1. A method for measuring aerodynamic aberration based on a high frame rate and high spatial resolution Hartmann, characterized in that: The measuring device used in this method includes a pulsed laser (1), a laser collimation module (2), an off-axis parabolic primary mirror (3), a focal length adjustment device (4), a collimating mirror (5), a stray light suppression module (6), an attenuation filter module (7), a microlens array (8), a magnification matching system (9), a photodetector (10), and a synchronous trigger device (11). The pulsed laser (1) and the laser collimation module (2) form a measuring light source. The off-axis parabolic primary mirror (3), the focal length adjustment device (4), the collimating mirror (5), the stray light suppression module (6), the attenuation filter module (7), the microlens array (8), the magnification matching system (9), the photodetector (10), and the synchronous trigger device (11) form a wavefront sensor. The measuring light source and the wavefront sensor are respectively arranged on both sides of the wind tunnel measurement window. The off-axis parabolic primary mirror (3), the focal length adjustment device (4), and the collimating mirror (5) constitute an off-axis beam reduction system. The beam emitted by the measuring light source passes through the aerodynamic flow field in the wind tunnel and then enters the wavefront sensor. After the beam diameter transformation and aberration transfer by the beam reduction module, the aerodynamic aberration is spatially segmented by the microlens array to form a dot matrix with a spatial offset relative to the ideal position. The magnification matching system images the dot matrix of the microlens array to the photodetector (10). The specific implementation steps are as follows: Step 1: Turn on the pulsed laser (1). The emitted beam passes through the laser collimation module (2) to obtain the beam emitted by the measuring light source. The beam emitted by the measuring light source passes through the aerodynamic flow field in the wind tunnel device and then enters the main beam reduction module of the wavefront sensor. Adjust the off-axis parabolic primary mirror (3) and the collimating mirror (5) so that their optical axes coincide and the distance between their vertices is less than the sum of their focal lengths. After adjustment, fix the positions of the off-axis parabolic primary mirror (3) and the collimating mirror (5). Then place the focal length adjustment device (4) in the optical path between the off-axis parabolic primary mirror (3) and the collimating mirror (5), and adjust to make the optical axis of the focal length adjustment device coincide with the optical axes of the off-axis parabolic primary mirror (3) and the collimating mirror (5). The emitted beam passes through the off-axis beam reduction system to complete the reduction of the incident beam diameter and is emitted to the stray light suppression module (6), and then passes through the attenuation filter module (7) and is emitted to the microlens array (8). The aerodynamic aberration is spatially segmented by the microlens array (8) to form a dot matrix with a spatial offset relative to the ideal position. The magnification matching system (9) images the distorted wavefront sub-light spot dot matrix image formed by the microlens array (8) to the photodetector (10). The photodetector (10) is connected to the synchronous trigger device (11) at the back to achieve synchronous acquisition of the aerodynamic aberration of the light source and the photodetector (10); Step 2: Extract the sub-light spot image on the photodetector (10), calculate the offset of the sub-light spot relative to the calibrated position through the spot positioning technology, and calculate the wavefront slope using the offset of the sub-light spot; Step 3: Restore the wavefront of the incident light beam through a wavefront restoration algorithm. The high-frame-rate and high-spatial-resolution Hartmann wavefront sensor uses the modal method to restore the wavefront. According to the sub-aperture segmentation layout and the set Zernike aberration modes, a restoration matrix for calculating the aberration mode coefficients is constructed based on the centroid offset or slope data of the spot within the sub-aperture.

2. The pneumatic aberration measurement method based on a high frame rate and high spatial resolution Hartmann according to claim 1, wherein: The measurement light source described in Step 1 is a high-repetition-rate and narrow-pulse-width laser to achieve the acquisition under extremely short exposure of the aerodynamic aberration.

3. A method for measuring aerodynamic aberration based on a high frame rate and high spatial resolution Hartmann, as claimed in claim 1, wherein: The main beam reduction module of the wavefront sensor described in Step 1 can be an off-axis beam reduction system composed of an off-axis parabolic mirror, a focal length adjustment device, and a collimating mirror, or any optical system that can achieve beam aperture transformation.

4. A method for measuring aerodynamic aberration based on a high frame rate and high spatial resolution Hartmann, as claimed in claim 1, wherein: The synchronization trigger device (11) described in Step 1 is connected to the light source and the photodetector (10). When measuring the aerodynamic aberration, the synchronization trigger device (11) sends a synchronization trigger signal to the pulsed laser (1) and the photodetector (10) according to a preset frequency. After receiving the trigger signal, the pulsed laser (1) emits a laser pulse, and the photodetector (10) starts to acquire images.

5. A method for measuring aerodynamic aberration based on a high frame rate and high spatial resolution Hartmann, as claimed in claim 1, wherein: The magnification matching system (9) described in Step 1 images the distorted wavefront sub-spot array image formed by the microlens array (8) onto the photodetector (10), and its magnification is a fixed imaging magnification or can also be a variable imaging magnification system.

6. The pneumatic aberration measurement method based on a high frame rate and high spatial resolution Hartmann according to claim 1, wherein: When the main beam reduction module and the magnification matching system (9) described in Step 1 have variable magnifications, by adjusting the magnifications of the main beam reduction module and the magnification matching system (9), aerodynamic aberration detection with variable spatial resolution and variable sampling frequency can be achieved without changing the structure of the measurement system.

7. A method for measuring aerodynamic aberration based on a high frame rate and high spatial resolution Hartmann, as claimed in claim 1, wherein: The spot positioning techniques described in Step 2 include the weighted centroid method, the threshold centroid method, the matched filtering method, the registration algorithm, or any other method that can position the spot location.

8. A method for measuring aerodynamic aberration based on a high frame rate and high spatial resolution Hartmann, as described in claim 1, wherein: The wavefront restoration algorithms described in Step 3 include the modal method and the regional method, which are methods that can achieve wavefront restoration from the sub-spot array data of the Hartmann sensor.

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