A chopping-type ultra-high-speed high-temporal-spatial resolution sequential shadow imaging system

Abstract

The present invention discloses a chopping type ultra-high speed high temporal and spatial resolution sequential shadow imaging system, which relates to the field of ultra-high speed imaging technology, including: a coupler for sending a light beam emitted by a multi-cavity light source subsystem into an optical fiber; a collimator for converting a divergent light beam output by an optical fiber into a parallel light beam; an imaging mirror for converging the parallel light beam passing through a test area to an imaging subsystem; a data acquisition and processing subsystem for imaging images of the test area at different times, and for remotely transmitting and processing the imaged images; a timing control subsystem; and also includes: a liquid homogenization mechanism arranged on the optical fiber output path. The present invention provides a chopping type ultra-high speed high temporal and spatial resolution sequential shadow imaging system, and takes into account ultra-high speed sequential front light imaging. Through the liquid homogenization technology, the background uniformity of each image will be greatly improved, and the imaging resolution will be improved accordingly.

Description

Technical Field

[0001] The present invention relates to the technical field of ultra-high-speed imaging, and more specifically to a chopping-type ultra-high-speed high-temporal-spatial resolution sequential shadow imaging system. Background Art

[0002] With the development of my country's aerospace technology and basic disciplines, research in the fields of ultra-high-speed aerodynamics, ultra-high-speed collisions, explosions and shocks, combustion and chemical reactions has continued to deepen. In these research works, many phenomena are ultra-high-speed transient change processes that last only microseconds or even nanoseconds. A multi-sequence imaging technology is needed to clearly and continuously image and record this process in order to grasp the essence of the physical phenomenon. In the various ultra-high-speed phenomenon studies currently carried out in the laboratory, the duration in a fixed test area is usually a few microseconds to tens of microseconds. For example, if the speed of the ultra-high-speed target is 10km / s (the ultra-high-speed phenomenon is usually lower than this value at present), and the size of the test area is 100mm, then the duration of the ultra-high-speed target in the test area is 10μs. If 4-8 ultra-high-speed target images can be obtained in the test area, it is sufficient to characterize the change process of the ultra-high-speed phenomenon, that is, its frame rate is at least 400,000-800,000 frames / second. If the ultra-high-speed target speed is lower than 10km / s, the ultra-high-speed phenomenon will last longer in the test area, and more images can be obtained at the same frame rate. In order to avoid large blur caused by the movement of the target when recording the image, the exposure time of each image must be short enough. It is usually required that the motion blur of the recorded image is less than 1 / 10 of the image resolution, and the recorded image is considered to meet the clear imaging requirements.

[0003] At present, the ultra-high-speed imaging equipment with an amplitude frequency of more than 10 million frames per second using microchannel plate (MCP) technology at home and abroad has an image pixel of about 1.3 million and adopts two imaging methods. One has only one imaging channel, and its frame rate is inversely proportional to the image pixel. The frame rate is about 20,000 frames per second at full frame, and the pixel is about 20,000 when the highest frame rate is 1 million frames per second; the other adopts the framing imaging method, and 4 channels are required to shoot 4 images. The Xi'an Institute of Optics and Precision Mechanics of the Chinese Academy of Sciences and Shenzhen University can produce rotating mirror framing film cameras with more than 8 sequences and a photosensitivity imaging time of more than 200 nanoseconds. Due to the use of mechanical rotation, the photosensitivity time of each image is difficult to be less than 100ns, and as the film production volume decreases, such cameras will be rarely used. The China Aerodynamics Research and Development Center has developed an ultra-high-speed imaging device based on "multi-light source spatial separation technology". When the shortest photosensitivity time is less than 10ns, the image pixels are greater than 10 million, achieving high temporal and spatial resolution imaging, and can effectively eliminate the self-luminescence of the test area. However, the light beams at different sequence moments are not coupled and output through the same optical fiber, and the coupling effects of different optical fibers, such as beam uniformity and coupling efficiency, will be different. In addition, the optical axes entering the test area are inconsistent, which will cause the imaging angle of each image to be inconsistent with the test area. In addition, due to the different optical path structures when imaging different sequences, the background spot quality of different sequence images will also be different. Figure 1 These are shadow images of the test target obtained at different sequence moments. The interval between images is 6µs (corresponding to an amplitude frequency of 1.67 million frames per second). The pixels of each image exceed 10 million. However, the background uniformity and brightness of different images vary greatly, and the overlap of the test areas corresponding to the 8 images is less than 95%.

[0004] In summary, in order to meet the requirements of multi-sequence imaging of ultra-high-speed target change processes, a variety of ultra-high-speed imaging technologies have been developed in China. Their common characteristics are the realization of higher frame rates and shorter photosensitivity times, but it is difficult to achieve high temporal resolution (shorter photosensitivity time) and higher spatial resolution at the same time. The use of "multi-light source spatial separation technology" has achieved higher temporal and spatial resolution, but there are characteristics of inconsistent test areas and inconsistent image quality in different sequences.

[0005] For the above problems, corresponding solutions have also been proposed in the prior art, such as Figure 4-Figure 8 As shown in the patent application number: 202111626236.2, a solution is proposed in a coaxial ultra-high-speed multi-sequence laser shadow imaging device, and the principle of the solution is as follows:

[0006] like Figure 4As shown, it discloses that a light beam emitted from a multi-cavity light source subsystem 1 enters an optical fiber 3 through a coupler 2, a divergent light beam 4 passes through a collimator 5 to form a parallel light beam, the parallel light beam passes through a test area 6 and enters an imaging mirror 7, the imaging mirror 7 converges the parallel light beam and enters an imaging subsystem 8, the imaging subsystem 8 performs equal optical path separation on the light beam to form multiple light beams, the data acquisition and processing subsystem 9 images the images of the test area 6 at different times and performs remote transmission and processing of the images, the timing control subsystem 10 controls the multi-cavity light source subsystem 1 to flash at different times, and at the same time controls the data acquisition and processing subsystem 9 to turn on the camera and collect images within a certain flash time period, and this optical path realizes ultra-high-speed high-temporal-space resolution sequential shadow imaging.

[0007] Figure 5 is a schematic diagram of the multi-cavity light source subsystem. Figure 3 The first laser head 101, the second laser head 102, the third laser head 103, and the fourth laser head 104 share a control and power supply system 105. The first laser head 101 enters the coupler 2 through the beam splitter I 106 and the beam splitter II 107, the second laser head 102 enters the coupler 2 through the reflector I 108, the beam splitter I 106, and the beam splitter II 107, the third laser head 103 enters the coupler 2 through the beam splitter III 109 and the beam splitter II 107, and the fourth laser head 104 enters the coupler 2 through the reflector II 110, the beam splitter III 109, and the beam splitter II 107.

[0008] Figure 6 801 collimates the convergent light beam of the imaging mirror 7 and then converges it through the imaging lens II 802. The convergent light beam passes through the beam splitter V 807, the beam splitter IV 805 and the reflector III 803 and then enters the first short-time light-sensitive camera 804 (referred to as the first camera for short). The convergent light beam passes through the beam splitter V 807 and the beam splitter IV 805 and then enters the second short-time light-sensitive camera 806 (referred to as the second camera for short). The convergent light beam passes through the beam splitter V 807, the beam splitter VI 808 and the reflector V 811 and then enters the third short-time light-sensitive camera 810 (referred to as the third camera for short). The convergent light beam passes through the beam splitter V 807, the beam splitter VI 808 and the reflector IV 809 and then enters the fourth short-time light-sensitive camera 812 (referred to as the fourth camera for short).

[0009] Figure 7Schematic diagram of the signal of the timing controller 10, the horizontal axis is the time when the signal is provided, and the vertical axis is the TTL signal. When the first TTL signal I 905 in the S1 timing sequence is provided to the first camera 804, the camera 804 starts to sense light for about 1 μs. When the first TTL signal I 905 is provided to the first camera 804 and then provided to the first TTL signal II 901 in the S2 timing sequence of the multi-cavity optical system after a delay of 10ns-200ns, the first laser head 101 flashes; when the second TTL signal I 906 in the S1 timing sequence is provided to the second camera 806, the camera 806 starts to sense light for about 1 μs. When the second TTL signal I 906 is provided to the second camera 806 and then provided to the second TTL signal II 902 in the S2 timing sequence of the multi-cavity optical system after a delay of 10ns-200ns, the second laser head 102 flashes; when the third TTL signal 907 is provided to the third camera 810, the camera 810 starts to sense light for about 1 μs. About 1 μs, when the third TTL signal I 907 in the S1 sequence is provided to the third camera 810 and then, after a delay of 10ns-200ns, is provided to the third TTL signal II 903 in the multi-cavity optical system S2 sequence, the third laser head 103 flashes; when the fourth TTL signal 908 is provided to the fourth camera 812, the camera 812 starts to sense light about 1 μs, when the fourth TTL signal I 908 in the S1 sequence is provided to the fourth camera 812 and then, after a delay of 10ns-200ns, is provided to the fourth TTL signal II 904 in the multi-cavity optical system S2 sequence, the fourth laser head 104 flashes.

[0010] But the focus of this technology is: Figure 8 As shown, the black vertical lines in the eight different sequence images are inconsistent in width because different sequence laser beams pass through different axes of the test area. This vertical line is caused by placing a thin plate in the test area. In addition, different sequence laser beams pass through different optical elements, resulting in inconsistent background brightness in other areas outside the black particles in the image. However, in actual applications, due to the Gaussian effect of the laser beam, the cross section perpendicular to the propagation direction of the beam will be uneven. This uneven beam will cause the recorded image background to be uneven when it is expanded and irradiated to the test area, affecting the imaging resolution. In addition, the original disclosed imaging optical path cannot achieve ultra-high-speed sequence front-light imaging, which limits its application scenarios. Summary of the invention

[0011] An object of the present invention is to solve at least the above problems and / or disadvantages and to provide at least the advantages which will be described hereinafter.

[0012] In order to achieve these purposes and other advantages of the present invention, a chopping-type ultra-high-speed, high-temporal-space-resolution sequential shadow imaging system includes: a coupler that sends a light beam emitted by a multi-cavity light source subsystem into an optical fiber; a collimator that converts a divergent light beam output by the optical fiber into a parallel light beam; an imaging mirror that converges the parallel light beam passing through a test area to an imaging subsystem; a data acquisition and processing subsystem that images the test area at different times and performs remote transmission and processing of the imaged images; a timing control subsystem that controls the multi-cavity light source subsystem to flash at different times and controls the data acquisition and processing subsystem to turn on the camera and collect images within the corresponding flash time period to achieve ultra-high-speed, high-temporal-space-resolution sequential shadow imaging; and is characterized in that it also includes: a liquid homogenization mechanism arranged on the optical fiber output path.

[0013] Preferably, the liquid homogenizing mechanism is configured to include:

[0014] A hard tube provided at the output end of the optical fiber;

[0015] A liquid disposed in the rigid tube for homogenizing the light beam;

[0016] A transparent glass sheet is placed inside the hard tube and located at both ends of the liquid to seal the liquid.

[0017] Preferably, the liquid homogenizing mechanism further comprises:

[0018] A condenser is arranged at the front end of the rigid tube.

[0019] Preferably, it further comprises: a sequential front light imaging subsystem for acquiring front light information of the test target at different times.

[0020] Preferably, the sequential front light imaging subsystem splits the incoming light beam into four groups of light beams with equal optical path length through an imaging lens group and a beam splitter group, and uses cameras arranged on different optical paths to respectively record the light beams of different groups;

[0021] Among them, the shortest exposure time of each camera is 1μs, and the shortest interval time between different images when acquiring 4 shadow images is 1μs;

[0022] Corresponding imaging lenses are respectively arranged on the optical path at the rear end of the beam splitter that splits the input light beam into two.

[0023] Preferably, the method further includes applying a chopping type ultra-high speed high temporal and spatial resolution sequential shadow imaging system, wherein for laser beams of different sequences, during the ultra-high speed target change process, the imaging time segment is divided and chopped into multiple microsecond time segments, so as to perform multiple equal optical path splitting on the imaging light path of the shadow image in different time segments, and then receive the target images after different splitting through different short-sensitivity time cameras;

[0024] The actual exposure time of different camera target surfaces is set to be synchronized with the flash time of the corresponding sequence pulse laser light source.

[0025] The present invention includes at least the following beneficial effects: the present invention uses the chopping imaging technology to achieve consistency in the test area and consistency in the quality of different sequence images while meeting higher temporal and spatial resolutions, and through the liquid homogenization technology, the background uniformity of each image will be greatly improved, and the imaging resolution will be improved accordingly. Different laser light source illumination methods and imaging methods can be used to achieve ultra-high-speed, high temporal and spatial resolution sequence shadow and front light imaging, respectively.

[0026] Other advantages, objectives and features of the present invention will be embodied in part through the following description, and in part will be understood by those skilled in the art through study and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 A schematic diagram of laser beam transmission and homogenization according to the present invention;

[0028] Figure 2 It is a schematic diagram of the cooperation between the ultra-high speed high temporal and spatial resolution sequential front light imaging subsystem and its components of the present invention;

[0029] Figure 3 for Figure 2 Schematic diagram of the mid-sequence front-light imaging subsystem;

[0030] Figure 4 It is a composition principle diagram of ultra-high speed high temporal and spatial resolution sequence shadow imaging in the prior art;

[0031] Figure 5 It is a schematic diagram of the principle of a multi-cavity light source subsystem in the prior art;

[0032] Figure 6 It is a schematic diagram of the principle of a sequential shadow imaging subsystem in the prior art;

[0033] Figure 7 It is a schematic diagram of the principle of a timing controller in the prior art;

[0034] Figure 8 In the prior art, eight different sequence images are obtained by laser beams of different sequences passing through different axes of the test area;

[0035] Among them, multi-cavity light source subsystem 1, the first laser head 101, the second laser head 102, the third laser head 103, the fourth laser head 104, the power supply system 105, the beam splitter I 106, the beam splitter II 107, the reflector I 108, the beam splitter III 109, the reflector II 110, the coupler 2, the optical fiber 3, the high energy threshold optical fiber 301, the liquid 302, the condenser 303, the transparent glass sheet 311, the divergent beam 4, the collimator 5, the test area 6, the imaging mirror 7, the imaging subsystem 8, the imaging lens I 801, the imaging lens II 802, the reflector III 803, the first short-time photosensitivity camera 804, the beam splitter IV 805, the second short-time Photosensitive camera 806, beam splitter V 807, beam splitter VI 808, reflector IV 809, third short-time photosensitive camera 810, reflector V 811, fourth short-time photosensitive camera 812, imaging lens III 814, imaging lens IV 815, data acquisition and processing subsystem 9, first TTL signal II 901, second TTL signal II 902, third TTL signal II 903, fourth TTL signal II 904, first TTL signal I 905, second TTL signal I 906, third TTL signal I 907, fourth TTL signal I 908, timing control subsystem 10, sequential front-light imaging subsystem 11. DETAILED DESCRIPTION

[0036] The present invention is further described in detail below in conjunction with the accompanying drawings so that those skilled in the art can implement the invention with reference to the description.

[0037] The present invention provides a chopping-type ultra-high-speed, high-temporal-spatial resolution sequential shadow imaging system, which can achieve consistency in the optical axis and optical path structure of different sequential imaging, can image the same test area, and at the same time maintain the background quality of the imaging spot. By combining the liquid homogenization technology at the transmission end of the optical fiber to the light, the laser beam spot is relatively uniform, the image background uniformity is greatly improved, and the image resolution is further improved. By adjusting the optical path structure in the imaging system and combining a multi-cavity pulsed laser light source, ultra-high-speed sequential front light imaging is achieved.

[0038] Specifically, the present invention utilizes the prior art that multiple sequence multi-cavity pulse lasers share a set of high homogenization devices, optical fiber coupling devices collimated optical paths and imaging optical paths, synchronizes the flash time of different pulse lasers with the photosensitivity time of different cameras, and thus realizes an ultra-high-speed high-temporal-spatial resolution shadow imaging technology. Ultra-high-speed sequence front light imaging can also be realized by directly illuminating the test target through a sequence light source and combining with photosensitivity cameras at different times. Since the laser beams flashing at different times pass through the same test area in terms of geometric structure, the characteristics of consistent optical axes, consistent test area ranges and consistent imaging spot quality of different sequence imaging can be achieved. The photosensitivity time of different sequence images can be realized by changing the flash time of different sequence pulse lasers. The frame rate depends on the shortest photosensitivity time of the camera, the time resolution depends on the pulse time of each sequence laser, and the pixel of each image depends on the pixel of the photosensitive target surface of the camera. Since the laser pulse time reaches nanoseconds or even shorter, and the pixel of the camera target surface can easily exceed tens of millions, it is easy to perform high-speed time resolution and spatial resolution imaging of ultra-high-speed targets through this technology. However, due to the Gaussian effect of the laser beam, the cross section perpendicular to the propagation direction of the beam will be uneven. This uneven beam will cause the recorded image background to be uneven when it is irradiated to the test area after expansion, affecting the imaging resolution. In order to achieve a higher homogenization effect on the laser beam and to transmit the beam more flexibly, a high-energy threshold optical fiber is connected to the coupler of the laser beam at one end and to a hard tube filled with liquid at the other end. In this way, the laser beam is first homogenized by the optical fiber and then further homogenized by the liquid, ensuring that the light spot after the laser beam expansion is more uniform, and the obtained image background is also more uniform, which correspondingly improves the imaging resolution.

[0039] Specifically, the chopping-type ultra-high-speed and high-temporal-spatial resolution sequential shadow imaging system mainly includes:

[0040] The multi-cavity light source subsystem is used to form a sequence of laser beams irradiated to the test area. It consists of multiple cavities and a control system or each cavity corresponds to an independent power control system. If four images need to be obtained in one test, four cavities are required. If eight images need to be obtained in one test, eight cavities are required.

[0041] The fiber-coupled homogenization system couples, transmits and homogenizes the flash beams of the multi-cavity light source. Since the peak power of the laser flash is high, the coupler and optical fiber in the fiber-coupled homogenization system need to meet the requirements of high-energy threshold laser spot. When the shadow imaging method is used, it needs to be combined with the parallel light transmission imaging device. When the front light imaging is used, the test area is directly illuminated by the optical fiber beam expansion.

[0042] The parallel light transmission imaging device consists of a set of collimating mirrors and imaging mirrors with consistent parameters. The relative apertures of the collimating mirror and the imaging mirror are usually about 1 / 10. The starting point of the light beam emitted from the fiber coupling system is located at the focal length of the collimating mirror. The light beam forms a parallel light beam after passing through the collimating mirror. After passing through the test area, the parallel light beam enters the imaging mirror and begins to converge.

[0043] Imaging subsystem, the imaging subsystem includes a series of beam splitters, reflectors and lenses. The beam splitters and reflectors perform equal optical path splitting on the converged light beam. If four images need to be obtained in one test, four equal optical path optical paths need to be formed. If eight images need to be obtained in one test, eight equal optical path optical paths need to be formed. When selecting a certain imaging mode of shadow and front light, the position and number of lenses in the system need to be adjusted accordingly;

[0044] Data acquisition and processing subsystem: The short-time photosensitive camera in the data acquisition and processing subsystem receives the image of the test area, transmits the obtained image to the computer, and processes the image;

[0045] The control system sends out TTL signals in a certain sequence, controls the multi-cavity light source subsystem to flash sequentially in a set sequence, and controls multiple short-time light-sensitive cameras to turn on and off in a certain sequence.

[0046] like Figure 1 As shown, the laser beam is firstly flexibly transmitted and homogenized through the high-energy threshold optical fiber 301, a hard tube with liquid 302 is placed at the output end of the high-energy threshold optical fiber 301, and transparent glass sheets 311 for sealing the liquid are arranged inside the hard tube and located at both ends of the liquid. The laser beam is further homogenized by the liquid 302. In order to reduce the divergence angle of the laser beam, a condenser 303 can be placed in front of the hard tube. This scheme allows flash beams of different sequences to share one set of fiber-coupled homogenization system; at the same time, one optical fiber and one hard tube with liquid are used to realize flexible transmission of multiple sequence laser beams and high-quality homogenization, so that the background quality of the obtained images of different sequences is basically consistent.

[0047] like Figure 2As shown, in actual application, 4 sequential pulse laser beams can be emitted through the same coupler 2 and enter the same optical fiber 3, and the divergent beam 4 directly illuminates the test area 6. The reflected light of the test area 6 at different times is recorded by different cameras in the sequential front light imaging subsystem 11, so as to obtain the front light information of the test target at different times. The timing control subsystem 10 synchronously controls the flash time of the laser head in the multi-cavity light source subsystem 1 and the camera opening time in the sequential front light imaging subsystem 11. At the same time as the flash, the data acquisition and processing subsystem 9 performs front light imaging on the images of the test area 6 at different times and performs remote transmission and processing of the images, so as to realize the ultra-high-speed high-temporal-spatial resolution sequential shadow imaging control method. Figure 7 The same timing is the same. This scheme enables multiple sequence light beams to pass through the test area through the same optical path, that is, the imaging optical paths at different times can remain strictly consistent in spatial position. At the same time, the actual photosensitivity time for sequential imaging of the test area is determined by the flash time of the light beams in different sequences, and the highest frame rate is determined by the shortest photosensitivity time of the camera. Since the flash time of the laser beam is short, the camera target surface pixels can be higher, and the image has a higher uniformity background, it can meet the requirements of high-speed ultra-high-speed phenomena for multiple sequences of high-temporal and spatial resolution imaging.

[0048] like Figure 3 As shown, the sequence front light imaging subsystem is Figure 6 On the basis of, the position of imaging lens 802 is adjusted to be closer to the position of imaging lens 801, and imaging lens III 814 and imaging lens IV 815 are added at the same time to meet the front light imaging of the test target. The parameters of imaging lens III 814 and imaging lens IV 815 are exactly the same. Multiple sequences of front light imaging of the test target are realized through this optical path. This scheme realizes high-resolution shadow and front light imaging through local changes in the optical path.

[0049] When the present invention applies the chopping type ultra-high speed high time and space resolution sequence shadow imaging, the multi-cavity light source subsystem uses a series of reflectors and beam splitters to realize that the light beams emitted from different cavities output pulse laser beams at the same position and perform optical fiber and liquid homogenization. The laser beams emitted at different times enter the same optical fiber through the coupler of the same optical fiber coupling system and are coupled and output, and generate parallel light beams after passing through the parallel light transmission imaging device. The parallel light beams converge and enter the imaging subsystem after passing through the test area. The imaging subsystem performs equal optical path separation on the light beams. Different short-time photosensitivity cameras in the data acquisition and processing subsystem receive the spectral images at different positions according to a certain time sequence. When the multi-cavity light source subsystem flashes for the first time at the starting point of the first time period, the camera opens its target surface and starts to sense light at the starting point of the second sequence time period before the multi-cavity light source subsystem flashes for the second time. The camera opens its target surface and starts to sense light at the starting point of the second sequence time period. In this order, the camera opens its target surface and starts to sense light in the third, fourth and other time periods. The actual photosensitivity time of each camera is determined by the flash time of the laser light source of the corresponding sequence. The data acquisition and processing subsystem is used for the processing of the laser light source. The processing subsystem remotely transmits the image to the computer and performs post-processing of the image. The control system controls the flash time of different sequences of laser beams of the light source system and the opening and closing time of the camera. Furthermore, the present invention cuts the test target into different time periods (that is, the time process of the ultra-high-speed test target to be tested is cut into multiple time periods. If 4 images need to be obtained for the test target, it is cut into 4 identical time periods within the test target time, which are the first time period, the second time period, the third time period and the fourth time period. Similarly, if 8 images need to be obtained, it is cut into 8 identical time periods within the test target time), so that the corresponding camera is turned on before the flash of different cavity beams, and the corresponding camera is turned off after the flash is completed. The time resolution depends on the shortest photosensitivity time of the camera and the flash time of the laser light source, and the spatial resolution depends on the collimated light path, the imaging light path, the camera target surface and the pixel size. At the same time, the sequence laser light source illuminates the test target after flashing according to a given time sequence, and the corresponding camera images the test target in each illumination stage to obtain an ultra-high-speed sequence front light image.

[0050] The chopping type ultra-high speed multi-sequence laser shadow technology of the present invention adopts a multi-cavity light source to share a light path outlet and liquid homogenization technology, and laser beams of different sequences share a set of imaging light paths to enter the parallel light transmission device and the imaging spectrometer. By dividing and chopping different imaging time periods, different cameras are used for photosensitization in different time periods and synchronized with different laser flash times, to achieve multi-sequence shadow imaging of ultra-high speed phenomena, and by changing the illumination mode of the multi-cavity light source and the optical path structure of the imaging system, ultra-high speed sequence front light imaging is achieved. Because the coaxiality of the optical paths of different sequences and the same optical elements are used, the consistency of the image quality of different sequences is guaranteed, and the use of liquid homogenization technology and the like achieves a higher uniform background, further improving the imaging resolution.

[0051] The above solution is only an illustration of a preferred embodiment, but is not limited thereto. When implementing the present invention, appropriate replacement and / or modification can be performed according to user needs.

[0052] The number of devices and processing scales described here are used to simplify the description of the present invention. Applications, modifications and variations of the present invention will be obvious to those skilled in the art.

[0053] Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and the embodiments. It can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily realized. Therefore, without departing from the general concept defined by the claims and equivalent scope, the present invention is not limited to the specific details and the illustrations shown and described here.

Claims

1. A chopping type ultra-high speed high temporal and spatial resolution sequential shadow imaging system, comprising: A coupler for sending the light beam emitted by the multi-cavity light source subsystem into the optical fiber; a collimator for converting the divergent light beam output by the optical fiber into a parallel light beam; a parallel light beam passing through the test area is converged to the imaging mirror of the imaging subsystem; a data acquisition and processing subsystem for imaging the images of the test area at different times, and for remotely transmitting and processing the imaged images; a timing control subsystem for controlling the multi-cavity light source subsystem to flash at different times, and at the same time controlling the data acquisition and processing subsystem to turn on the camera and collect images within the corresponding flash time period, so as to realize ultra-high-speed high-temporal-spatial resolution sequence shadow imaging; characterized in that it also includes: a liquid homogenization mechanism arranged on the optical fiber output path; The liquid homogenizing mechanism is configured to include: A hard tube provided at the output end of the optical fiber; A liquid disposed in the rigid tube for homogenizing the light beam; Transparent glass sheets arranged in the hard tube and located at both ends of the liquid for sealing the liquid; The liquid homogenizing mechanism also includes: A condenser lens is arranged at the front end of the rigid tube; It also includes: a sequence front light imaging subsystem for acquiring front light information of a test target at different times; The sequential front light imaging subsystem splits the incoming light beam into four groups of light beams with equal optical path length through an imaging lens group and a beam splitter group, and uses cameras arranged on different optical paths to respectively record the light beams of different groups; Among them, the shortest exposure time of each camera is 1μs, and the shortest interval time between different images when acquiring 4 shadow images is 1μs; Corresponding imaging lenses are respectively arranged on the optical path at the rear end of the beam splitter that splits the input light beam into two.

2. The chopping type ultra-high speed high temporal and spatial resolution sequential shadow imaging system according to claim 1, characterized in that: The method also includes a method of applying a chopping ultra-high speed high temporal and spatial resolution sequence shadow imaging system, wherein for different sequences of laser beams, during the ultra-high speed target change process, the imaging time segment is divided and chopped into multiple microsecond time segments, so as to perform multiple equal optical path splitting on the imaging light path of the shadow image in different time segments, and then receive the target images after different splitting through different short-sensitivity time cameras; The actual exposure time of different camera target surfaces is set to be synchronized with the flash time of the corresponding sequence pulse laser light source.

Images