Fine scanning control methods and systems for field of view extension and small target recognition

Abstract

This invention discloses a fine scanning control method and system for field-of-view expansion and small target recognition, belonging to the field of laser imaging technology. The system includes an optical path unit, a gimbal, a single-photon detector, a TCSPC system, and a control unit. The optical path unit is a coaxial transceiver optical path; the gimbal is used for large field-of-view scanning; the control unit connects the telescope, galvanometer, gimbal, TCSPC system, and laser, and is used to emit control and synchronization signals. The system obtains distance by acquiring echo signals through the single-photon detector, adjusts the telescope focal length to obtain target object information by adjusting the distance, and calculates the scanning steps and step size using a fine scanning method. The control unit controls the galvanometer and high-precision two-axis gimbal to achieve two-order fine scanning of a large field of view, solving the problem of low imaging resolution for small targets at long distances. The control unit controls the galvanometer, gimbal, and TCSPC system to achieve large field-of-view, super-resolution imaging while maintaining the fine features of the target object.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of laser imaging technology, and particularly relates to a fine scanning control method and system for field of view expansion and small target identification. BACKGROUND

[0002] Laser imaging technology is the main development direction of three-dimensional imaging technology. Traditional imaging technology cannot meet the application requirements of optical identification of weak targets due to limitations of detection sensitivity, dynamic range, etc. In recent decades, the vigorous development of quantum technology has provided a new technical means for breaking through the detection limit of traditional technology. Single-photon imaging technology based on quantum technology has single-photon sensitivity and picosecond time resolution, breaking the technical shackles that traditional laser imaging systems can only increase laser power and telescope aperture to improve the detection signal intensity, signal-to-noise ratio and detection distance. Single-photon imaging technology has a single-photon level limit detection sensitivity and can realize extremely weak optical signal sensing. Its superior performance and broad application prospects have attracted widespread attention from countries around the world.

[0003] However, when the imaging distance expands to a certain extent, the imaging field of view will be limited and the small target intensity in the field of view is weak relative to the background noise, and the echo light signal is easily overwhelmed by noise. Although the field of view can be expanded by scanning, and the echo light intensity can be improved by increasing the output power of the laser, small target signals are still difficult to identify and the imaging resolution cannot be improved, so long-distance small target imaging is still a challenging technical problem and an important technology in urgent need of development. SUMMARY

[0004] In view of the deficiencies of the prior art, the application provides a fine scanning control method and system for field of view expansion and small target identification, thereby solving the problems of field of view expansion limitation and low imaging resolution for small target object identification in the field of view of the traditional single-photon imaging system caused by long-distance detection.

[0005] To solve the above problems, the application provides a fine scanning control method for field of view expansion and small target identification, comprising the following steps:

[0006] S1, a single-chip microcomputer controls a cloud platform moving surface of a light path unit to face the target object direction, the light path unit includes a telescope, a galvanometer, a hole mirror, a coupling device, a laser, and a polarization beam splitter prism; the single-chip microcomputer sends a pulse trigger signal to the laser to control the laser to emit laser, which is irradiated to the target object through a transmitting and receiving coaxial light path, the echo signal returns along the original path, is reflected by the hole mirror into the coupling device, and a single-photon detector detects the echo signal in the coupling device;

[0007] S2, the time-correlated single photon counting (TCSPC) system collects a photon counting signal, calculates the photon flight time through a processor to obtain the distance of the target object, and then sends the distance signal to a single-chip microcomputer;

[0008] S3, the single-chip microcomputer obtains the distance signal, zooms the telescope to determine the image information of the target object, calculates the scanning step number and step length of the galvanometer and the two-axis holder in a fine scanning mode, and then controls the galvanometer and the two-axis holder to realize two-stage fine scanning in a snake scanning mode.

[0009] S4, after two-stage fine scanning, the processor obtains the three-dimensional information of the target object, processes and splices the three-dimensional information of the target object by a point cloud three-dimensional reconstruction method, and realizes imaging of the target object.

[0010] Further, in step S3, the specific operation of zooming the telescope is that the single-chip microcomputer obtains the distance, controls the step motor driver, and then drives the zoom device to zoom the telescope to obtain an observation image with a resolution of the target object higher than a preset pixel threshold.

[0011] Further, in step S3, the scanning step number and step length of the galvanometer and the two-axis holder are calculated in a fine scanning mode, and the specific process is as follows:

[0012]

[0013] holder step length = θ;

[0014] wherein d is the size of a single pixel field of view, L is the distance of the target object, θ is the maximum deflection angle of the galvanometer, V represents the maximum output voltage of the DAC module, and N is the imaging pixel size. It can be seen that, with the change of the distance and the size of a single pixel, different scanning step lengths and step numbers of the MEMS galvanometer and the holder can be obtained, so that a super-resolution target object image can be obtained.

[0015] Further, in step S3, the DAC control module is used to output two-way positive and negative analog voltages to control the galvanometer movement, the DAC control module includes a chip and a reference voltage circuit, the single-chip microcomputer sends a voltage signal to the chip of the DAC control module through SPI, and then the DAC module outputs an analog voltage to the galvanometer to control its movement.

[0016] Further, in step S3, the specific operation of the single-chip microcomputer controlling the galvanometer and the holder to realize two-stage fine scanning in a snake scanning mode is as follows:

[0017] In the first stage, the single-chip microcomputer firstly controls the galvanometer to perform a snake-shaped scan according to the calculated galvanometer step length and galvanometer step number, and outputs a pixel pulse synchronization signal every time the analog voltage value is changed, and outputs a line pulse synchronization signal when a row is scanned, until a subgraph is scanned by the snake-shaped scan;

[0018] In the second stage, after the single-chip microcomputer outputs a frame pulse synchronization signal after the first stage scans a subgraph, the single-chip microcomputer controls the holder to perform a snake-shaped scan according to the calculated holder step length and holder step number, turns to the next subgraph, and repeats the operation of the first stage until all the holder steps are completed, so that a large field of view is scanned.

[0019] The present application also provides a fine scanning control system for field of view expansion and small target identification, which comprises a holder, an optical path unit, a control unit, a single-photon detector and a time-dependent single-photon counting system.

[0020] The holder is used to rotate the optical path unit, expand the imaging range, and realize large field of view scanning imaging.

[0021] The optical path unit is used to adjust the pointing direction of the pulsed laser after the laser emits pulsed laser, and then emit pulsed laser to the target imaging area, and when the pulsed laser irradiates the target object, the reflected echo optical signal is obtained. The optical path unit collects the target echo optical signal, filters out stray light and noise, and then collects and couples the filtered echo optical signal into the single-photon detector.

[0022] The single-photon detector is used to detect the target echo signal coupled to the optical fiber by the coupling device, and process the received echo signal into a photon counting signal.

[0023] The control unit is used to collect the photon counting signal, obtain the distance of the target object according to the photon counting signal, calculate the scanning step length and step number by adjusting the focal length of the telescope combined with the fine scanning mode, continue to adjust the pointing direction of the laser pulse and give each pixel point a synchronization signal until the large field of view scanning of the target object area is completed, process the scanning information of the target object to realize imaging, and display the imaging result.

[0024] The time-dependent single-photon counting system is used to receive the photon counting signal, and measure the flight time of the emitted signal photon and the returned signal photon under the action of the synchronization signal output by the control unit, so as to obtain the distance of the target object.

[0025] Further, the holder is a two-axis holder.

[0026] Further, the light path unit comprises a telescope, a galvanometer, a perforated mirror, a coupling device, a polarization beam splitter, a laser;

[0027] The telescope is used to collect echo signals reflected from a target object irradiated by a laser, and then the echo signals enter the coupling device through a transceiving coaxial light path and are guided to the single-photon detector;

[0028] The galvanometer is used to change the direction of laser emission, thereby realizing scanning of the target object;

[0029] The coupling device is used to couple the collected echo signals into the single-photon detector;

[0030] The perforated mirror is used to realize the transceiving coaxial light path and change the direction of the light path;

[0031] The polarization beam splitter is used to transmit polarized light of a laser pulse;

[0032] The laser is used to receive a laser trigger signal and emit a laser pulse.

[0033] Further, the control unit comprises a DAC control module, a galvanometer controller, a stepper motor driver, a zoom device, a processor, and a single-chip microcomputer;

[0034] The DAC control module is used to output an analog voltage to control the movement of the galvanometer;

[0035] The galvanometer controller is used to receive the analog voltage output by the DAC control module and drive the movement of the galvanometer;

[0036] The stepper motor driver is used to drive the movement of the stepper motor;

[0037] The zoom device is used to realize automatic zooming of the telescope through the movement of the stepper motor;

[0038] The processor is used to process the photon counting information collected by a time-dependent single-photon counting system, calculate the distance of the target object, and send the distance to the single-chip microcomputer; and is also used to process the target object imaging area after scanning according to a scanning logic combined with a normalization algorithm, realize imaging of the target object, and display the imaging.

[0039] The single-chip microcomputer is used for outputting a trigger signal to the laser and outputting a synchronization signal to the time-correlated single-photon counting system, and is also used for calculating the distance of the target object, zooming the telescope, determining the target object position, and calculating the scanning step number and step length of the galvanometer and the holder by combining a fine scanning mode, so that the galvanometer and the holder are controlled to realize large field of view two-stage fine scanning of the target object.

[0040] Further, the zooming device drives a gear by a stepping motor to realize zooming of the telescope.

[0041] The present application has the following advantages:

[0042] (1) The present application calculates the scanning step number and step length by distance measurement of the target object and a fine scanning mode, so that super-resolution imaging of the target object is realized.

[0043] (2) The present application uses a high-precision two-axis holder and a galvanometer as a scanning unit, and realizes large field of view three-dimensional scanning imaging of a long-distance target object by controlling the high-precision two-axis holder and the galvanometer.

[0044] (3) The present application realizes high signal-to-noise ratio imaging of a long-distance small target by adjusting the focal length of the telescope, which is beneficial to image recognition. BRIEF DESCRIPTION OF DRAWINGS

[0045] Figure 1 A working principle schematic diagram of a fine scanning control system for field of view expansion and small target recognition is provided for the embodiment of the present application.

[0046] Figure 2 An electronic control system scheme of a fine scanning control system for field of view expansion and small target recognition is provided for the embodiment of the present application.

[0047] Figure 3 A flow chart of a fine scanning control method for field of view expansion and small target recognition is provided for the embodiment of the present application.

[0048] In the figure: 1 NUC processor; 2 MCU single-chip microcomputer; 3 TCSPC system; 4 zooming device; 5 stepping motor driver; 6 galvanometer controller; 7 DAC control module; 8 single-photon detector; 9 two-axis holder; 10 polarization beam splitter prism; 11 laser; 12 hole mirror; 13 coupling device; 14 MEMS galvanometer; 15 telescope; 16 target object. DETAILED DESCRIPTION

[0049] In order to facilitate the understanding of the present application, the present application will be described in more detail below in conjunction with the accompanying drawings and specific embodiments. The preferred embodiments of the present application are shown in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described in the specification. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without making creative efforts fall within the scope of protection of the present application.

[0050] The present application designs a set of field of view expansion and small target recognition system based on fine scanning control technology, which can realize super-resolution imaging of small target objects at a long distance under good atmospheric conditions.

[0051] Figure 1 It is a working principle diagram of a field of view expansion and small target recognition system based on fine scanning control technology in an embodiment of the present application. As can be seen from the figure, the main devices include: NUC processor 1, MCU single-chip microcomputer 2, TCSPC system 3, zoom device 4, stepper motor driver 5, galvanometer controller 6, DAC control module 7, single-photon detector 8, two-axis holder 9, polarization beam splitter prism 10, laser 11, aperture mirror 12, coupling device 13, MEMS galvanometer 14, telescope 15, target object 16.

[0052] In the embodiment of the present application, the connection relationship and action of each component are as follows: the MCU single-chip microcomputer 2 outputs a trigger signal to the laser 11 to emit pulsed laser, the laser pulse passes through the polarization beam splitter prism 10 and the aperture mirror 12, the light beam is reflected by the MEMS galvanometer 14 and passes through the telescope 15 to irradiate the target object 14; the reflected echo signal returns by the original route, enters the coupling device 13 after being reflected by the aperture mirror 12, and couples the echo signal into the optical fiber to connect the single-photon detector 8. The single-photon detector 8 processes the echo signal into a photon counting signal, the TCSPC system 3 collects the photon counting signal, the NUC processor 1 obtains the distance of the target object 16 by calculating the photon flight time through the TCSPC system 3, and then transmits it to the MCU single-chip microcomputer 2. The MCU single-chip microcomputer 2 controls the stepper motor driver 5 to make the zoom device 4 zoom the telescope 15 and calculates the step length and number of the MEMS galvanometer 14 and the high-precision two-axis holder 9 in combination with the fine scanning mode. The MCU single-chip microcomputer 2 controls the MEMS galvanometer 14 and the high-precision two-axis holder to realize super-resolution large field of view scanning. The NUC processor 1 obtains the three-dimensional information of the target object 16, processes and splices the three-dimensional information of the target object by a point cloud three-dimensional reconstruction method, and realizes super-resolution and large field of view imaging of the target object.

[0053] In the embodiment of the present application, MCU single-chip microcomputer and NUC processor are used to control the system, the NUC processor is the main control, and the MCU single-chip microcomputer is auxiliary control, the system is controlled, and super-resolution imaging of small target objects in the field of view is realized.

[0054] In the embodiment of the present application, the optical path unit adopts coaxial design of receiving and transmitting, the deflection angles of receiving and transmitting can be consistent, strict synchronization in time can be ensured, the need of high-speed scanning can be met, there is no parallax problem, efficient imaging under different distances can be realized without adjusting the receiving and transmitting optical axes.

[0055] In the embodiment of the present application, a pulse laser 11 with a wavelength of 905nm is used.

[0056] In the embodiment of the present application, the wavelength detection range of the single-photon detector 8 is 400-1060nm, and the dark count is 50cps.

[0057] In the embodiment of the present application, the time resolution of the TCSPC system 3 is 16ps, and the maximum count value of the unit is 65535.

[0058] In the embodiment of the present application, the minimum rotation angle of a single dimension of the MEMS galvanometer 14 is 0.5urad, and the scanning range is 10mrad.

[0059] In the embodiment of the present application, the precision of the high-precision two-axis holder 9 is 0.01°, the horizontal rotation angle is 0-360°, and the pitch rotation angle is -90°-90°.

[0060] In the embodiment of the present application, the precision of the DAC control module output voltage is 1mv, and the analog voltage signal of ±10V can be output.

[0061] Figure 2An electronic control system scheme provided for the specific embodiment system of the present application, as shown in the figure, the electronic control system mainly consists of two parts, firstly, MCU single-chip microcomputer, the MCU single-chip microcomputer controls high-precision two-axis holder by RS485, controls the voltage signal of galvanometer controller to realize large field of view scanning of target field of view by DAC module controlled by SPI, controls stepping motor driver by PWM to make zoom device zoom the telescope, and outputs synchronous signal to laser and TCSPC system to mark the scanning process of target object, at the same time, communicates with NUC processor through USART; and the NUC processor mainly sends synchronous signal to MCU single-chip microcomputer through USART, and receives photon counting information recorded by TCSPC system through USB3.0, processes according to scanning logic combined with normalization algorithm, realizes imaging of target object and displays. Among them, the DAC control module is used to output two-way positive and negative 10V analog voltage to control the movement of the galvanometer, and the DAC control module mainly has DAC8830IDR chip and reference voltage circuit; the MCU single-chip microcomputer is connected with the DAC8830IDR chip through SPI, the single-chip microcomputer sends voltage signal to the DAC8830IDR chip through SPI, and then the DAC module outputs analog voltage to the MEMS galvanometer to make it move.

[0062] The control flow in the process of completing one scanning imaging is as follows Figure 3The single photon detector and the TCSPC system are initialized first, then the gimbal and the MEMS mirror are initialized, after the initialization is completed, the MCU single-chip microcomputer sends a pulse trigger signal to the laser, the NUC processor calculates the flight time to obtain the distance after detecting the echo signal, the zoom control of the telescope is performed according to the distance, so that the observation image of the target object with a resolution higher than a preset pixel threshold in the field of view is obtained, the preset pixel threshold in the embodiment is 8*8, the MCU single-chip microcomputer controls the gimbal to point to the target object; the MEMS mirror scanning step and the number of steps are calculated through the distance and the size of a single pixel, the imaging pixel size is input, and the gimbal scanning step and the number of steps are calculated in combination with the MEMS mirror scanning step and the number of steps; the MCU single-chip microcomputer controls the MEMS mirror to point to the first pixel point of the first subgraph, and then starts scanning, the MCU single-chip microcomputer sends the mirror X-axis control information and outputs the pixel pulse signal, whether the TCSPC system receives the line pulse signal, if the line pulse signal is not received, the previous step is continued to be executed, if the line pulse signal is received, the MCU single-chip microcomputer sends the mirror Y-axis control signal and outputs the pixel pulse signal, whether the TCSPC system receives the frame pulse signal, if the frame pulse signal is not received, the previous step is continued to be executed, if the frame pulse signal is received, the MCU single-chip microcomputer controls the gimbal to point to the direction of the next subgraph, and then judges whether it is the last subgraph, if not, the subgraph scanning is continued, if yes, the NUC processes the data according to the normalization algorithm, and splices the subgraphs into a large graph according to the scanning order, so that the target object imaging is realized and display is performed, and the scanning imaging is ended.

[0063] The MEMS mirror in the embodiment is controlled by the MCU single-chip microcomputer to perform fine scanning on the target object sub-field of view in a snake-shaped scanning mode, so that the fine field of view is scanned, the high-precision two-axis gimbal is controlled by the MCU single-chip microcomputer to perform coarse scanning on the target object large field of view in a snake-shaped scanning mode, so that the scanning field of view is expanded, and the MCU single-chip microcomputer controls the two to realize the large field of view scanning while maintaining the fine features of the target object.

[0064] The application aims to solve the problems of the traditional single photon imaging system, such as the field of view expansion limitation caused by long-distance detection and the low imaging resolution when a small target object is identified in the field of view. The application adjusts the focal length of the telescope according to the distance to obtain the information of the small target object, calculates the scanning step and the number of steps in combination with the fine scanning mode, adopts two-stage fine field of view scanning to improve the resolution of the system, and realizes the super-resolution imaging of the small target object at a long distance, which has important significance for emergency rescue, investigation and early warning fields.

[0065] It should be noted that the various steps / components described in the present application can be split into more steps / components or two or more steps / components or parts of the operation of steps / components can be combined into new steps / components, as required by implementation, to achieve the objectives of the present application.

[0066] Those skilled in the art will easily understand that the above description is only the preferred embodiment of the present application and is not intended to limit the present application, and any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A fine scanning control method for field of view extension and small target identification, characterized in that, The method comprises the following steps: S1, a single-chip microcomputer controls a gimbal moving towards a target object direction, and a light path unit comprising a telescope, a galvanometer, a hole mirror, a coupling device, a laser, and a polarization beam splitter is mounted on the gimbal; the single-chip microcomputer sends a pulse trigger signal to the laser to control the laser to emit laser light, which is irradiated to the target object through a transmitting and receiving coaxial light path, and a return signal returns to the coupling device through the hole mirror; a single-photon detector detects the return signal in the coupling device; S2, a time-correlated single-photon counting system collects photon counting signals, calculates the photon flight time through a processor to obtain the distance of the target object, and then sends the distance signal to the single-chip microcomputer; S3, the single-chip microcomputer obtains the distance signal, zooms the telescope to determine the image information of the target object, and calculates the scanning steps and step length of the galvanometer and the gimbal in a fine scanning mode; then, the single-chip microcomputer controls the galvanometer and the gimbal to realize two-stage fine scanning in a snake scanning mode; S4, after two-stage fine scanning, the processor obtains the three-dimensional information of the target object, processes and splices the three-dimensional information of the target object by a point cloud three-dimensional reconstruction method, and realizes imaging of the target object.

2. The method for fine scanning control for field of view extension and small target identification according to claim 1, characterized in that, In step S3, the specific operation of zooming the telescope is that the single-chip microcomputer obtains the distance, controls a step motor driver, and then drives a zoom device to zoom the telescope, so as to obtain an observation image with a resolution of the target object higher than a preset pixel threshold.

3. The method for fine scanning control for field of view extension and small target identification according to claim 1, characterized in that, In step S3, the scanning steps and step length of the galvanometer and the two-axis gimbal are calculated in a fine scanning mode, and the specific process is as follows: pan tilt step = θ; Wherein, d is the size of a single-pixel field of view, L is the distance of the target object, θ is the maximum polarization angle of the galvanometer, V represents the maximum output voltage of the DAC module, and N is the size of the imaging pixel.

4. The method for fine scanning control for field of view extension and small target identification according to claim 3, characterized in that, In step S3, the DAC control module is used for outputting two-way positive and negative analog voltage to control the movement of the galvanometer; the DAC control module comprises a chip and a reference voltage circuit; the single-chip microcomputer sends a voltage signal to the chip of the DAC control module through SPI, and then the DAC module outputs analog voltage to the galvanometer to control the movement of the galvanometer.

5. The method for fine scanning control for field of view extension and small target identification according to claim 1, characterized in that, In step S3, the specific operation of the single-chip microcomputer controlling the galvanometer and the gimbal to realize two-stage fine scanning in a snake scanning mode is as follows: In the first stage, the single-chip microcomputer first controls the galvanometer to perform snake scanning according to the calculated galvanometer step length and galvanometer step number; the single-chip microcomputer outputs a pixel pulse synchronization signal every time the analog voltage value is changed, and outputs a line pulse synchronization signal when scanning a row, until a sub-image is scanned by snake scanning; In the second stage, after the single-chip microcomputer outputs a frame pulse synchronization signal after scanning a sub-image in the first stage, the single-chip microcomputer controls the gimbal to perform snake scanning according to the calculated gimbal step length and gimbal step number, and turns to the next sub-image, and the operation of the first stage is repeated until all gimbal steps are completed, to realize large field of view scanning imaging.

6. A fine scanning control system for field of view extension and small target identification, characterized by, The method comprises a gimbal, a light path unit, a control unit, a single-photon detector, and a time-correlated single-photon counting system; The gimbal is used for rotating the light path unit, expanding the imaging range, and realizing large field of view scanning imaging; The light path unit is used for adjusting the beam pointing of the pulsed laser after the laser emits the pulsed laser, and then emitting the pulsed laser to the target imaging area, and when the pulsed laser irradiates the target object, a return light signal is reflected; the light path unit collects the target return light signal, filters out stray light and noise, and then collects and couples the filtered return light signal into a single photon detector; The light path unit changes the pointing of the pulsed laser to realize point-by-point scanning of the target object; The single photon detector is used for detecting the target return signal coupled to the optical fiber by the coupling device, and processing the received return signal into a photon counting signal; The control unit is used for collecting the photon counting signal, and obtaining the distance of the target object according to the photon counting signal, calculating the scanning step and the number of steps by adjusting the focal length of the telescope combined with the fine scanning mode, and continuously adjusting the pointing of the laser pulse and outputting a synchronization signal to each pixel point until the large field of view scanning of the target object imaging area is completed, processing the scanning information of the target object to realize imaging, and displaying the imaging result; The time-correlated single photon counting system is used for receiving the photon counting signal, and measuring the flight time of the emitted signal photon and the return signal photon under the action of the synchronization signal output by the control unit, and then obtaining the distance of the target object.

7. The fine scanning control system for field of view extension and small target identification according to claim 6, characterized in that, The holder is a two-axis holder.

8. The fine scanning control system for field of view extension and small target identification according to claim 6, characterized in that, The light path unit includes a telescope, a galvanometer, a hole mirror, a coupling device, a polarization beam splitter prism, and a laser; The telescope is used for collecting the return signal reflected by the target object irradiated by the laser, and then entering the coupling device through the coaxial light path to guide into the single photon detector; The galvanometer is used for changing the direction of the laser emitted by the laser to realize scanning of the target object; The coupling device is used for coupling the collected return signal into the single photon detector; The hole mirror is used for coaxial light path and changing the direction of the light path; The polarization beam splitter prism is used for transmitting the pulsed laser polarization light; The laser is used for receiving a laser trigger signal and emitting a pulsed laser.

9. The fine scan control system for field of view extension and small target identification of claim 8, wherein, The control unit includes a DAC control module, a galvanometer controller, a stepper motor driver, a zoom device, a processor, and a single-chip microcomputer; The DAC control module is used for outputting an analog voltage to control the movement of the galvanometer; The galvanometer controller is used for receiving the analog voltage output by the DAC control module to drive the movement of the galvanometer; The stepper motor driver is used for driving the movement of the stepper motor; The zoom device realizes automatic zooming of the telescope through the movement of the stepper motor; The processor is used for processing the photon counting information collected by the time-correlated single photon counting system, calculating the distance of the target object, and sending the distance to the single-chip microcomputer; It is also used for processing according to the scanning logic combined with the normalization algorithm after completing the scanning of the target object imaging area, realizing the imaging of the target object, and displaying the imaging result; The single-chip microcomputer is used for outputting a trigger signal to the laser and a synchronization signal to the time-correlated single photon counting system. The zoom device drives the gear by the step motor movement, so as to realize zooming of the telescope.

10. The fine scanning control system for field of view extension and small target identification of claim 9, wherein, The zoom device drives the gear by the step motor movement, so as to realize zooming of the telescope.

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