Dual-receiving complementary enhanced cat eye detection system

Abstract

A dual-receiving complementary enhanced cat eye detection system comprises an echo receiving unit I, an echo receiving unit II, a synchronous control and signal processing unit and a laser lighting unit. According to the invention, by adopting the double-connection optical detection system, two synchronous laser echo images are subjected to superposition fusion and complementary enhancement, and two synchronous detection images are subjected to superposition fusion, so that laser echoes are enhanced, and random noise and noisy points are eliminated. Therefore, the detection probability of the whole system is improved and the false alarm rate is reduced. For detection in motion, due to the fact that a double-receiving optical detection system is adopted, the scanning effect caused in the motion process is eliminated, and enhanced noise and noisy points are eliminated, so that the scanning characteristic of the system in motion is greatly improved, the scanning speed of 20 degrees per second can be achieved, and rapid scanning detection is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of optical detection, and in particular to a dual-receiving complementary enhanced cat's eye detection system. Background Art

[0002] The cat's eye detection system is mainly based on the "cat's eye" effect, that is, using the reflection characteristics of optical equipment such as sights, photoelectric probes, and telescopes to detect their positions. The basic principle is that the device emits laser beams to the target area, and these laser beams are usually invisible light bands. When the laser beam illuminates the optical window of the threatening target and enters the field of view of its optical system, according to the reversibility of the optical path, the optical system will return part of the laser signal along the original optical path. The return characteristics of these laser echo signals are independent of the incident angle of the laser incident optical system. At the same time, the intensity of the echo of this type of target is 2 to 4 orders of magnitude higher than that of the diffuse reflection target, forming a reflection phenomenon similar to the cat's eye at night. This is the "cat's eye effect" phenomenon of the optical target, and this optical target is called a "cat's eye target", thereby realizing the detection of specific optical targets.

[0003] Traditional cat's eye detection equipment is configured with a laser emitting light source, a receiving optical system and an image processing device. In a scenario where the equipment is fixed, laser detection is performed on a fixed area. In order to improve the efficiency and range of detection, the laser energy is evenly dispersed at a certain beam divergence angle through the laser emitting lens. Therefore, the reflected laser echo energy is actually very weak. In order to amplify this weak energy, the signal gain of the photoelectric conversion detector is usually large, which brings a lot of random noise and noise points in the picture. On the other hand, when the detection device moves faster, the detector needs insufficient integration time for imaging, and the emitted echo signal is constantly changing, which will cause more random noise and noise points.

[0004] The above two points lead to the high false alarm rate and low detection probability of traditional cat-eye devices during rapid movement, which limits the use of the device in scenarios such as mobile platforms, where search and panoramic detection are required, and where a large area needs to be scanned quickly. Summary of the invention

[0005] The purpose of the present invention is to provide a dual-receiving complementary enhanced cat's eye detection system, comprising: an echo receiving unit I, an echo receiving unit II, a synchronous control and signal processing unit, and a laser lighting unit.

[0006] The laser lighting unit is used to output laser to illuminate the detection area.

[0007] The echo receiving unit I is used to collect background light signals to form a detection area image.

[0008] The echo receiving unit I includes a CMOS sensor I and a CMOS sensor II.

[0009] The CMOS sensor I is used to perform photoelectric conversion on the background light signal collected by the echo receiving unit I to form a background image I.

[0010] The CMOS sensor II is used to perform photoelectric conversion on the background light signal collected by the echo receiving unit I to form a background image II.

[0011] The echo receiving unit II is used to collect laser echo signals to form a laser echo picture.

[0012] The echo receiving unit II includes a CMOS sensor III and a CMOS sensor IV.

[0013] The CMOS sensor III is used to perform photoelectric conversion on the laser echo signal collected by the echo receiving unit II to form an echo image I.

[0014] The CMOS sensor IV is used to perform photoelectric conversion on the laser echo signal collected by the echo receiving unit II to form an echo image II.

[0015] The synchronous control and signal processing unit processes the background image I and the background image II to form a detection area image.

[0016] The synchronous control and signal processing unit processes the echo image I and the echo image II to form a laser echo picture.

[0017] The synchronous control and signal processing unit fuses and superimposes the imaging of the detection area and the laser echo picture to form a cat's eye detection picture, and detects and identifies the cat's eye target in the cat's eye detection picture through a detection algorithm to obtain the position of the cat's eye target.

[0018] Furthermore, the cat's eye detection system also includes an optical bench.

[0019] The optical bench is used to carry the echo receiving unit I, the echo receiving unit II, the synchronous control and signal processing unit, and the laser lighting unit.

[0020] Furthermore, the echo receiving unit II is fixed on the optical bench.

[0021] The echo receiving unit I is stacked on the echo receiving unit II.

[0022] The synchronous control and signal processing unit and the laser lighting unit are both fixedly mounted on the optical bench.

[0023] The laser illumination unit is close to the signal receiving end of the echo receiving unit II, and the synchronization control and signal processing unit is far away from the signal receiving end of the echo receiving unit II.

[0024] Furthermore, the pulse wavelength, pulse width, pulse frequency and pulse power of the laser are all adjustable.

[0025] Furthermore, the distance range of the laser echo signal collected by the echo receiving unit II is 50m to 2000m.

[0026] Furthermore, the processing performed by the synchronization control and signal processing unit on the background image I and the background image II includes superposition, fusion, noise removal, and noise removal.

[0027] Furthermore, the processing performed by the synchronization control and signal processing unit on the echo image I and the echo image II includes superposition, fusion, noise removal, and noise removal.

[0028] Furthermore, the scanning speed of the cat's eye detection system is as follows:

[0029]

[0030] Where v is the scanning speed of the cat's eye detection system. τ is the integration time. α is the detection field of view of the echo receiving unit. m is the pixel resolution. n is the maximum allowable offset.

[0031] Furthermore, the cat's eye detection system is also built into a target geometric feature filtering algorithm.

[0032] Furthermore, the cat's eye detection system is applied to scanning and detecting moving targets.

[0033] The technical effect of the present invention is unquestionable. The present invention adopts a dual receiving optical system to compare and strengthen the echo on the detector of the laser echo channel in each receiving lens, and superimpose and fuse them into a new echo picture, thereby enhancing the echo intensity, increasing the detection probability, and eliminating the influence of the echo misalignment during the movement of the detector, resulting in insufficient integration time and thus reducing the echo intensity. The detector pictures of the image detection channel in each receiving lens are superimposed and de-jittered to eliminate the screen drag.

[0034] The present invention adopts a dual-receiving optical system, and the random noise and noise points in the original echo images output by the two receiving detectors will not be consistent. After the final images are superimposed and fused, the image noise and noise points will be eliminated, thereby reducing the false alarm rate of the system.

[0035] The present invention adopts a dual-connection optical detection system to superimpose and fuse two synchronous laser echo images for complementary enhancement, and superimpose and fuse two synchronous detection images to enhance the laser echo and eliminate random noise and noise points, thereby improving the detection probability of the entire system and reducing the false alarm rate.

[0036] For detection during motion, since the present invention adopts a dual-receiving optical detection system, the scanning effect caused by the motion process is eliminated, and the enhanced noise and noise points are eliminated, thereby greatly improving the scanning characteristics of the system during motion, and can achieve a scanning speed of 20° / s, realizing rapid scanning detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 This is a diagram of the composition of the cat's eye detection system;

[0038] Figure 2 This is a schematic diagram of the overall composition of the cat's eye detection system; Figure 2 (a) is a schematic diagram of the whole machine composition I; Figure 2 (b) is a schematic diagram of the whole machine II;

[0039] Figure 3 This is the working flow chart of the cat's eye detection system;

[0040] Figure 4 This is a schematic diagram of the echo intensity caused by the scanning effect; Figure 4 (a) is a schematic diagram of the echo intensity of the echo receiving unit 1; Figure 4 (b) is a schematic diagram of the echo intensity of the echo receiving unit II; Figure 4 (c) is a schematic diagram of the echo intensity of two echo receiving units superimposed;

[0041] In the figure: echo receiving unit I1, echo receiving unit II2, synchronization control and signal processing unit 3, laser illumination unit 4, optical bench 5, CMOS sensor I6, CMOS sensor II7, CMOS sensor III8, CMOS sensor IV9. DETAILED DESCRIPTION

[0042] The present invention is further described below in conjunction with the embodiments, but it should not be understood that the above subject matter of the present invention is limited to the following embodiments. Without departing from the above technical ideas of the present invention, various substitutions and changes are made according to the common technical knowledge and customary means in the art, which should all be included in the protection scope of the present invention.

[0043] Embodiment 1:

[0044] See also Figures 1 to 4 The dual-receiving complementary enhanced cat's eye detection system includes: an echo receiving unit I1, an echo receiving unit II2, a synchronous control and signal processing unit 3, and a laser lighting unit 4.

[0045] The laser illumination unit 4 is used to output laser light to illuminate the detection area.

[0046] The echo receiving unit I1 is used to collect background light signals to form a detection area image.

[0047] The echo receiving unit I1 includes a CMOS sensor I6 and a CMOS sensor II7.

[0048] The CMOS sensor I6 is used to perform photoelectric conversion on the background light signal collected by the echo receiving unit I1 to form a background image I.

[0049] The CMOS sensor II7 is used to perform photoelectric conversion on the background light signal collected by the echo receiving unit I1 to form a background image II.

[0050] The echo receiving unit II2 is used to collect laser echo signals to form a laser echo picture.

[0051] The echo receiving unit II2 includes a CMOS sensor III8 and a CMOS sensor IV9.

[0052] The CMOS sensor III8 is used to perform photoelectric conversion on the laser echo signal collected by the echo receiving unit II2 to form an echo image I.

[0053] The CMOS sensor IV9 is used to perform photoelectric conversion on the laser echo signal collected by the echo receiving unit II2 to form an echo image II.

[0054] The synchronous control and signal processing unit 3 processes the background image I and the background image II to form a detection area image.

[0055] The synchronous control and signal processing unit 3 processes the echo image I and the echo image II to form a laser echo picture.

[0056] The synchronous control and signal processing unit 3 fuses and superimposes the imaging of the detection area and the laser echo picture to form a cat's eye detection picture, and detects and identifies the cat's eye target in the cat's eye detection picture through a detection algorithm to obtain the position of the cat's eye target.

[0057] Embodiment 2:

[0058] The dual-receiving complementary enhanced cat's eye detection system, the main technical content of which is shown in Example 1. Furthermore, the cat's eye detection system also includes an optical bench 5.

[0059] The optical bench 5 is used to carry the echo receiving unit I1 , the echo receiving unit II2 , the synchronous control and signal processing unit 3 , and the laser illumination unit 4 .

[0060] Embodiment 3:

[0061] The dual-receiving complementary enhanced cat's eye detection system, the main technical content of which is shown in any one of Embodiments 1 to 2, further, the echo receiving unit II2 is fixed on the optical bench 5.

[0062] The echo receiving unit I1 is stacked on the echo receiving unit II2.

[0063] The synchronous control and signal processing unit 3 and the laser illumination unit 4 are both fixedly mounted on the optical bench 5 .

[0064] The laser illumination unit 4 is close to the signal receiving end of the echo receiving unit II2, and the synchronization control and signal processing unit 3 is far away from the signal receiving end of the echo receiving unit II2.

[0065] Embodiment 4:

[0066] A dual-receiving complementary enhanced cat's eye detection system, the main technical content of which is shown in any one of Examples 1 to 3. Furthermore, the pulse wavelength, pulse width, pulse frequency and pulse power of the laser are all adjustable.

[0067] Embodiment 5:

[0068] The dual-receiving complementary enhanced cat's eye detection system, the main technical content of which is shown in any one of Examples 1 to 4. Furthermore, the distance range of the laser echo signal collected by the echo receiving unit II2 is 50m to 2000m.

[0069] Embodiment 6:

[0070] The dual-receiving complementary enhanced cat's eye detection system, the main technical content of which can be found in any one of embodiments 1 to 5. Furthermore, the processing performed by the synchronization control and signal processing unit 3 on the background image I and the background image II includes superposition, fusion, noise removal, and noise removal.

[0071] Embodiment 7:

[0072] The dual-receiving complementary enhanced cat's eye detection system, the main technical content of which can be found in any one of Examples 1 to 6. Furthermore, the processing performed by the synchronization control and signal processing unit 3 on the echo image I and the echo image II includes superposition, fusion, noise removal, and noise removal.

[0073] Embodiment 8:

[0074] The dual-receiving complementary enhanced cat's eye detection system, the main technical content of which is shown in any one of Embodiments 1 to 7. Further, the scanning speed of the cat's eye detection system is as follows:

[0075]

[0076] Where v is the scanning speed of the cat's eye detection system. τ is the integration time. α is the detection field of view of the echo receiving unit. m is the pixel resolution. n is the maximum allowable offset.

[0077] Embodiment 9:

[0078] The dual-receiving complementary enhanced cat's eye detection system, the main technical content of which is shown in any one of Embodiments 1 to 8. Furthermore, the cat's eye detection system is also equipped with a target geometric feature filtering algorithm.

[0079] Embodiment 10:

[0080] A dual-receiving complementary enhanced cat's eye detection system, the main technical content of which can be found in any one of Examples 1 to 9. Furthermore, the cat's eye detection system is applied to scanning and detecting moving targets.

[0081] Embodiment 11:

[0082] See also Figures 1 to 4 The dual-receiving complementary enhanced cat's eye detection system includes: an echo receiving unit I1, an echo receiving unit II2, a synchronous control and signal processing unit 3, and a laser lighting unit 4.

[0083] The laser illumination unit 4 is used to output 808nm infrared laser to illuminate the detection area and realize active illumination.

[0084] The echo receiving unit I1 is used to collect background light signals to form a detection area image.

[0085] The echo receiving unit I1 includes a CMOS sensor I6 and a CMOS sensor II7.

[0086] The CMOS sensor I6 is used to perform photoelectric conversion on the background light signal collected by the echo receiving unit I1 to form a background image I.

[0087] The CMOS sensor II7 is used to perform photoelectric conversion on the background light signal collected by the echo receiving unit I1 to form a background image II.

[0088] The echo receiving unit II2 is used to collect laser echo signals to form a laser echo picture.

[0089] The echo receiving unit II2 includes a CMOS sensor III8 and a CMOS sensor IV9.

[0090] The CMOS sensor III8 is used to perform photoelectric conversion on the laser echo signal collected by the echo receiving unit II2 to form an echo image I.

[0091] The CMOS sensor IV9 is used to perform photoelectric conversion on the laser echo signal collected by the echo receiving unit II2 to form an echo image II.

[0092] The synchronous control and signal processing unit 3 processes the background image I and the background image II to form a detection area image.

[0093] The synchronous control and signal processing unit 3 processes the echo image I and the echo image II to form a laser echo picture.

[0094] The synchronous control and signal processing unit 3 fuses and superimposes the imaging of the detection area and the laser echo picture to form a cat's eye detection picture, and detects and identifies the cat's eye target in the cat's eye detection picture through a detection algorithm to obtain the position of the cat's eye target.

[0095] The detection algorithm linearly projects the original two-dimensional image into a one-dimensional measurement vector by applying a random sampling matrix, extracts the "cat's eye" effect target information by processing the one-dimensional measurement vector, and then reconstructs an image containing only the "cat's eye" target through a restoration algorithm.

[0096] The cat's eye targets include white light optical / photoelectric equipment, white light / low light sights, telescopes, etc.

[0097] When the synchronous control and signal processing unit processes the signal from the CMOS sensor in the laser echo receiving unit, it detects a weak target signal, calculates the position of the target signal in the detector, gives the position coordinates of the center of the signal on the detector, and generates graphics and text characters at the same time; finally, the generated graphics and text characters are superimposed by color OSD and superimposed on the same position of the image generated by the imaging detector, and the position and image are output and reported.

[0098] The optical bench 5 is used to carry the echo receiving unit I1, the echo receiving unit II2, the synchronous control and signal processing unit 3, the laser illumination unit 4, the CMOS sensor I6, the CMOS sensor II7, the CMOS sensor III8, and the CMOS sensor IV9.

[0099] Working principle of the system: After the equipment is turned on under the control of the control terminal software command, first, the laser lighting unit is synchronously triggered to emit a laser with a certain pulse wavelength, pulse width, pulse frequency, and pulse power, which is shaped into a uniform lighting beam of about 8° through the built-in microlens array group. After most of the laser is shielded from stray light and transmitted through the optical window, it actively illuminates the scene and the target in the scene.

[0100] Then, a small part of the scattered laser light is received by the external sensor, generating a rising edge pulse, triggering the laser echo receiving unit I to work (collecting background light and clearly imaging the active laser search illumination area), and the second rising edge pulse triggers the laser echo receiving unit II (photoelectric imaging unit) to work;

[0101] When triggered by the first pulse, the echo receiving unit II receives the echo laser within the distance range of 50m to 2000m. The scene scattering signal collected by its CMOS sensor within the set integration time is photoelectrically converted and then sent to the synchronous control and signal processing unit for processing to generate the target. Since there are two identical CMOS sensors, two similar pictures will be formed.

[0102] The echo receiving unit I is triggered by the second pulse and then after a set delay, the signal collected within a certain integration time is converted by photoelectric conversion to generate a background light image for clear imaging. Since there are two identical CMOS sensors, two similar echo signal images will be formed.

[0103] The synchronous control and signal processing unit superimposes and fuses the two CMOS sensor images of the echo receiving unit I, removes the noise points and noise, forms the background light and clearly images the active laser search illumination area. The two CMOS sensor images of the echo receiving unit II are superimposed and fused, and the noise points and noise are removed to form the laser echo picture.

[0104] Finally, the synchronous control and signal processing unit fuses and superimposes the image of the echo receiving unit I and the image of the echo receiving unit II to form the final cat's eye detection image, and detects and identifies the cat's eye target through the detection algorithm. The workflow diagram is shown in the figure below: Figure 3 shown.

[0105] Embodiment 12:

[0106] The main technical content of the dual-receiving complementary enhanced cat's eye detection system is shown in Example 11. Furthermore, the cat's eye detection system also includes an optical bench 5.

[0107] The optical bench 5 is used to carry the echo receiving unit I1 , the echo receiving unit II2 , the synchronous control and signal processing unit 3 , and the laser illumination unit 4 .

[0108] Embodiment 13:

[0109] The dual-receiving complementary enhanced cat's eye detection system, the main technical content of which can be found in any one of Examples 11 to 12, further, the echo receiving unit II2 is fixed on the optical bench 5.

[0110] The echo receiving unit I1 is stacked on the echo receiving unit II2.

[0111] The synchronous control and signal processing unit 3 and the laser illumination unit 4 are both fixedly mounted on the optical bench 5 .

[0112] The synchronous control and signal processing unit 3 and the laser illumination unit 4 are both connected to the echo receiving unit II2.

[0113] The laser illumination unit 4 is close to the signal receiving end of the echo receiving unit II2, and the synchronization control and signal processing unit 3 is far away from the signal receiving end of the echo receiving unit II2.

[0114] The CMOS sensor I6 is installed on one side of the echo receiving unit I1 close to the synchronous control and signal processing unit 3 .

[0115] The CMOS sensor II7 is installed on the echo receiving unit I1 and is far away from the signal receiving end of the echo receiving unit I1.

[0116] The CMOS sensor III8 is installed on the echo receiving unit II2 and is far away from the signal receiving end of the echo receiving unit II2.

[0117] The CMOS sensor IV9 is installed on the echo receiving unit II2 at a side close to the synchronization control and signal processing unit 3 .

[0118] Embodiment 14:

[0119] A dual-receiving complementary enhanced cat's eye detection system, the main technical content of which is shown in any one of Examples 11 to 13. Furthermore, the pulse wavelength, pulse width, pulse frequency and pulse power of the laser are all adjustable.

[0120] Embodiment 15:

[0121] The dual-receiving complementary enhanced cat's eye detection system, the main technical content of which can be found in any one of Examples 11 to 14. Furthermore, the distance range of the laser echo signal collected by the echo receiving unit II2 is 50m to 2000m.

[0122] Embodiment 16:

[0123] The dual-receiving complementary enhanced cat's eye detection system, the main technical content of which can be found in any one of Examples 11 to 15. Furthermore, the processing performed by the synchronization control and signal processing unit 3 on the background image I and the background image II includes superposition, fusion, noise removal, and noise removal.

[0124] Embodiment 17:

[0125] The dual-receiving complementary enhanced cat's eye detection system, the main technical content of which can be found in any one of Examples 11 to 16. Furthermore, the processing performed by the synchronization control and signal processing unit 3 on the echo image I and the echo image II includes superposition, fusion, noise removal, and noise removal.

[0126] Embodiment 18:

[0127] The dual-receiving complementary enhanced cat's eye detection system, the main technical content of which is shown in any one of Examples 11 to 17. Further, under the conditions of meeting the design conditions of the farthest detection distance, detection probability and false alarm rate, the search efficiency of the cat's eye detection device is mainly related to the pulse width of the illumination light source and the integration time of the detector, the field of view angle of the echo receiving unit, and the resolution of the CMOS sensor in the scanning direction of the echo receiving unit. The scanning speed of the cat's eye detection system is as follows:

[0128]

[0129] Where v is the scanning speed of the cat's eye detection system. τ is the integration time. α is the detection field of view of the echo receiving unit. m is the pixel resolution. n is the maximum allowable offset.

[0130] Embodiment 19:

[0131] The dual-receiving complementary enhanced cat's eye detection system, the main technical content of which can be found in any one of Examples 11 to 18. Furthermore, the cat's eye detection system is also equipped with a target geometric feature filtering algorithm.

[0132] In order to increase the detection probability and reduce the false alarm rate, the cat's eye detection device usually requires the target geometric feature filtering algorithm to be inserted. Usually, the offset is required to be less than 1. Due to the scanning effect, the echo intensity diagram formed on the detector is as follows: Figure 4 shown.

[0133] Embodiment 20:

[0134] A dual-receiving complementary enhanced cat's eye detection system, the main technical content of which can be found in any one of Examples 11 to 19. Furthermore, the cat's eye detection system is applied to scanning and detecting moving targets.

[0135] Due to physical factors and manufacturing process limitations, although the same optical system and the same detection device are designed, their processing, manufacturing and assembly cannot be 100% consistent. In order to amplify weak signals, the cat's eye detection equipment controls the photoelectric conversion amplification gain of the detector to a relatively extreme level. Especially during movement, the optical signal is still changing due to insufficient integration time, which will cause more random noise and noise points.

[0136] For detection during motion, due to the use of a dual-receiving optical detection system, the scanning effect caused during motion is eliminated, and the enhanced noise and noise points are eliminated, thereby greatly improving the system's scanning characteristics during motion, achieving a scanning speed of 20° / s and realizing rapid scanning detection.

[0137] Embodiment 21:

[0138] See also Figures 1 to 4 , dual-receiving complementary enhanced cat-eye detection system, the main technical contents include:

[0139] The dual-receiving complementary enhanced cat's eye detection system is mainly composed of a laser illumination unit, a synchronous control and signal processing unit, an echo receiving unit I (including 2 CMOS sensors), an echo receiving unit II (including 2 CMOS sensors), and an optical bench. Figure 1 As shown, the appearance of the whole machine is as follows Figure 2 shown.

[0140] 1) Laser lighting unit: The device outputs 808nm infrared laser to illuminate the target area and realize active irradiation.

[0141] 2) Synchronous control and signal processing unit: When processing the signal from the CMOS sensor in the laser echo receiving unit, a weak target signal is detected, and the position of the target signal in the detector is solved and processed, and the position coordinates of the center position of the signal on the detector are given, and graphics and text characters are generated at the same time; finally, the generated graphics and text characters are superimposed by color OSD and superimposed on the same position of the image generated by the imaging detector, and the position and image are output and reported.

[0142] 3) Echo receiving units I and II: used to receive the emitted echo laser and collect background light and to clearly image the active laser search illumination area.

[0143] 4) Optical bench: Serves as the installation base for the echo receiving unit and laser illumination unit, and carries all components.

[0144] Working principle of the system: After the equipment is turned on under the control of the control terminal software command, first, the laser lighting unit is synchronously triggered to emit a laser with a certain pulse wavelength, pulse width, pulse frequency, and pulse power, which is shaped into a uniform lighting beam of about 8° through the built-in microlens array group. After most of the laser is shielded from stray light and transmitted through the optical window, it actively illuminates the scene and the target in the scene.

[0145] Then, a small part of the scattered laser light is received by the external sensor, generating a rising edge pulse, triggering the laser echo receiving unit I to work (collecting background light and clearly imaging the active laser search illumination area), and the second rising edge pulse triggers the laser echo receiving unit II (photoelectric imaging unit) to work;

[0146] When triggered by the first pulse, the echo receiving unit II receives the echo laser within the distance range of 50m to 2000m. The scene scattering signal collected by its CMOS sensor within the set integration time is photoelectrically converted and then sent to the synchronous control and signal processing unit for processing to generate the target. Since there are two identical CMOS sensors, two similar pictures will be formed.

[0147] The echo receiving unit I is triggered by the second pulse and then after a set delay, the signal collected within a certain integration time is converted by photoelectric conversion to generate a background light image for clear imaging. Since there are two identical CMOS sensors, two similar echo signal images will be formed.

[0148] The synchronous control and signal processing unit superimposes and fuses the two CMOS sensor images of the echo receiving unit I, removes the noise points and noise, forms the background light and clearly images the active laser search illumination area. The two CMOS sensor images of the echo receiving unit II are superimposed and fused, and the noise points and noise are removed to form the laser echo picture.

[0149] Finally, the synchronous control and signal processing unit fuses and superimposes the image of the echo receiving unit I and the image of the echo receiving unit II to form the final cat's eye detection image, and detects and identifies the cat's eye target through the detection algorithm. The workflow diagram is shown in the figure below: Figure 3 shown.

[0150] Under the design conditions of the longest detection distance, detection probability and false alarm rate, the search efficiency of the cat's eye detection equipment is mainly related to the pulse width of the illumination light source and the integration time of the detector, the field of view angle of the echo receiving unit, and the CMOS sensor resolution in the scanning direction of the echo receiving unit, which obeys the following formula:

[0151]

[0152] In the above formula, τ is the integration time defined in relation to the pulse width of the illumination light source and the integration time of the detector. In order to maximize the signal-to-noise ratio of the detector receiving signal, the pulse width and the integration time of the detector are generally the same; α is the staring detection field angle of the echo receiving unit; m is the pixel resolution of the echo receiving unit detector in the scanning direction; and n is the maximum allowable offset of the echo spot on the detector during the detector integration time due to the cat's eye detection device scanning and detecting targets at infinity.

[0153] In order to increase the detection probability and reduce the false alarm rate, the cat's eye detection device usually requires the target geometric feature filtering algorithm to be inserted. Usually, the offset is required to be less than 1. Due to the scanning effect, the echo intensity diagram formed on the detector is as follows: Figure 4 shown.

[0154] Due to physical factors and manufacturing process limitations, although the same optical system and the same detection device are designed, their processing, manufacturing and assembly cannot be 100% consistent. In order to amplify weak signals, the cat's eye detection equipment controls the photoelectric conversion amplification gain of the detector to a relatively extreme level. Especially during movement, the optical signal is still changing due to insufficient integration time, which will cause more random noise and noise points.

[0155] 1) A dual-receiving optical system is used to contrast and strengthen the echo on the detector of the laser echo channel in each receiving lens, and superimpose and fuse them into a new echo image, thereby enhancing the echo intensity, increasing the detection probability, and eliminating the impact of the echo misalignment during the movement of the detector, resulting in insufficient integration time and reduced echo intensity. The detector images of the image detection channel in each receiving lens are superimposed and de-jittered to eliminate the image smear.

[0156] 2) By adopting a dual-receiving optical system, the random noise and noise points in the original echo images output by the two receiving detectors will not be consistent. After the final images are superimposed and fused, the image noise and noise points will be eliminated, thereby reducing the false alarm rate of the system.

[0157] According to the design parameters of the optical system of the designed receiving module, the parameters of the selected sensor and the setting parameters of the receiving module, the field of view of the echo receiving unit staring detection is 8.4°; the pixel resolution of the echo receiving unit detector in the scanning direction is 960; the detector integration time is 200μs; in order to ensure the reliability of the design parameters and not affect the autonomous target recognition in the software algorithm, the pixel offset in the scanning direction is selected to be less than 0.5 pixels. It can be known that the theoretical calculation result of the scanning speed of the designed cat's eye detection equipment is:

[0158]

[0159] By adopting a dual-connection optical detection system, two synchronous laser echo images are superimposed and fused, and the two synchronous detection images are superimposed and fused to enhance the laser echo and eliminate random noise and noise points, thereby improving the detection probability of the entire system and reducing the false alarm rate.

[0160] For detection during motion, due to the use of a dual-receiving optical detection system, the scanning effect caused during motion is eliminated, and the enhanced noise and noise points are eliminated, thereby greatly improving the system's scanning characteristics during motion, achieving a scanning speed of 20° / s and realizing rapid scanning detection.

Claims

1. Dual-receiving complementary enhanced cat's eye detection system, characterized in that: include: An echo receiving unit I (1), an echo receiving unit II (2), a synchronization control and signal processing unit (3), and a laser illumination unit (4); The laser illumination unit (4) is used to output laser light to illuminate the detection area; The echo receiving unit I (1) is used to collect background light signals and form a detection area image; The echo receiving unit I (1) comprises a CMOS sensor I (6) and a CMOS sensor II (7); The CMOS sensor I (6) is used to perform photoelectric conversion on the background light signal collected by the echo receiving unit I (1) to form a background image I. The CMOS sensor II (7) is used to perform photoelectric conversion on the background light signal collected by the echo receiving unit I (1) to form a background image II. The echo receiving unit II (2) is used to collect laser echo signals to form a laser echo image; The echo receiving unit II (2) comprises a CMOS sensor III (8) and a CMOS sensor IV (9); The CMOS sensor III (8) is used to perform photoelectric conversion on the laser echo signal collected by the echo receiving unit II (2) to form an echo image I; The CMOS sensor IV (9) is used to perform photoelectric conversion on the laser echo signal collected by the echo receiving unit II (2) to form an echo image II; The synchronous control and signal processing unit (3) processes the background image I and the background image II to form a detection area image; The synchronous control and signal processing unit (3) processes the echo image I and the echo image II to form a laser echo picture; The synchronous control and signal processing unit (3) fuses and superimposes the imaging of the detection area and the laser echo picture to form a cat's eye detection picture, and detects and identifies the cat's eye target in the cat's eye detection picture through a detection algorithm to obtain the position of the cat's eye target.

2. The dual-receiving complementary enhanced cat's eye detection system according to claim 1, characterized in that: The cat's eye detection system also includes an optical bench (5); The optical bench (5) is used to carry an echo receiving unit I (1), an echo receiving unit II (2), a synchronous control and signal processing unit (3), and a laser lighting unit (4).

3. The dual-receiving complementary enhanced cat's eye detection system according to claim 2, characterized in that: The echo receiving unit II (2) is fixed on the optical bench (5); The echo receiving unit I (1) is stacked on the echo receiving unit II (2); The synchronous control and signal processing unit (3) and the laser illumination unit (4) are both fixedly mounted on an optical bench (5); The laser illumination unit (4) is close to the signal receiving end of the echo receiving unit II (2), and the synchronous control and signal processing unit (3) is far away from the signal receiving end of the echo receiving unit II (2).

4. The dual-receiving complementary enhanced cat's eye detection system according to claim 1, characterized in that: The pulse wavelength, pulse width, pulse frequency and pulse power of the laser are all adjustable.

5. The dual-receiving complementary enhanced cat's eye detection system according to claim 1, characterized in that: The distance range of the laser echo signal collected by the echo receiving unit II (2) is 50m to 2000m.

6. The dual-receiving complementary enhanced cat's eye detection system according to claim 1, characterized in that: The processing performed by the synchronization control and signal processing unit (3) on the background image I and the background image II includes superposition, fusion, noise point removal, and noise removal.

7. The dual-receiving complementary enhanced cat's eye detection system according to claim 1, characterized in that: The processing performed by the synchronization control and signal processing unit (3) on the echo image I and the echo image II includes superposition, fusion, noise point removal, and noise removal.

8. The dual-receiving complementary enhanced cat's eye detection system according to claim 1, characterized in that: The scanning speed of the cat's eye detection system is as follows: Where v is the scanning speed of the cat's eye detection system; τ is the integration time; α is the detection field of view of the echo receiving unit; m is the pixel resolution; and n is the maximum allowable offset.

9. The dual-receiving complementary enhanced cat's eye detection system according to claim 1, characterized in that: The cat's eye detection system also incorporates a target geometric feature filtering algorithm.

10. The dual-receiving complementary enhanced cat's eye detection system according to any one of claims 1 to 9, characterized in that: The cat's eye detection system is applied to scanning and detecting moving targets.

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