Laser radar receiving system and laser radar

Abstract

The present invention discloses a laser radar receiving system for receiving the reflected light beam of the laser radar; comprising: a photosensitive receiving array, comprising at least one photosensitive array, each photosensitive array comprising 2n photosensitive elements, n is greater than 1, and at least two of the 2n photosensitive elements are neither in the same row nor in the same column; the area of ​​the photosensitive array is less than or equal to a preset area value, so that the reflected light spot formed when the reflected light beam of the laser radar is irradiated on the photosensitive receiving array can hit all the photosensitive elements in a photosensitive array at the same time; at least one signal processing circuit is set in a one-to-one correspondence with at least one photosensitive array, and each signal processing circuit is connected to the 2n photosensitive elements in the corresponding photosensitive array, and is used to perform multiplication operation on the signals output by the 2n photosensitive elements in the corresponding photosensitive array to obtain and output the target signal. The present invention can improve the signal-to-noise ratio of the output signal. The present invention also discloses a laser radar.

Description

Technical Field

[0001] The present invention relates to the field of laser technology, and in particular to a laser radar receiving system and a laser radar. Background Art

[0002] LiDAR is a radar system that emits laser beams to detect the position, speed and other characteristic quantities of a target. It is widely used in the field of autonomous driving. Its working principle is to emit a detection signal (laser beam) to the target, and then compare the received signal reflected from the target (target echo) with the transmitted signal. After appropriate processing, relevant information about the target can be obtained, such as target distance, direction, height, speed, attitude, and even shape parameters, so as to detect, track and identify the target.

[0003] In actual work, LiDAR is easily affected by interfering light in the environment. When the environmental noise is large, the signal may not be detected normally. Therefore, how to obtain an output signal with a high signal-to-noise ratio has always been a problem that needs to be solved in the LiDAR production process. Summary of the invention

[0004] Based on this, it is necessary to propose a laser radar receiving system and a laser radar to address the above problems.

[0005] A laser radar receiving system, the system is used to receive a reflected light beam of a laser radar; the laser radar receiving system comprises: a photosensitive receiving array, comprising at least one photosensitive array, each of the photosensitive arrays comprising 2n photosensitive elements, n is greater than 1, and at least two of the 2n photosensitive elements are neither in the same row nor in the same column; the area of ​​the photosensitive array is less than or equal to a preset area value, so that the reflected light spot formed when the reflected light beam of the laser radar is irradiated on the photosensitive receiving array can hit all the photosensitive elements in one photosensitive array at the same time; at least one signal processing circuit is arranged in a one-to-one correspondence with the at least one photosensitive array, each of the signal processing circuits is connected to the 2n photosensitive elements in the corresponding photosensitive array, and is used to perform multiplication operations on the signals output by the 2n photosensitive elements in the corresponding photosensitive array to obtain a target signal, and output the target signal.

[0006] Wherein, the 2n photosensitive elements in each photosensitive array are arranged in a matrix.

[0007] Wherein, the 2n photosensitive elements in each of the photosensitive arrays are arranged along the circumferential direction.

[0008] The shape of the photosensitive elements is fan-shaped, and the centers of the photosensitive elements in the same photosensitive array are close to each other.

[0009] Each of the photosensitive arrays includes at least four photosensitive elements with the same structure, and the arcs of the photosensitive elements are located on the same circumference.

[0010] Wherein, the photosensitive surface areas of the 2n photosensitive elements in each of the photosensitive arrays are not completely equal.

[0011] Wherein, each of the signal processing circuits includes: 2n amplifiers, which are connected to the 2n photosensitive elements in a one-to-one correspondence, and are used to amplify the signals output by the 2n photosensitive elements; and / or each of the signal processing circuits also includes: 2n low-pass filters, which are connected to the 2n photosensitive elements in a one-to-one correspondence, and are used to filter the signals output by the 2n photosensitive elements.

[0012] Wherein, the gap between two adjacent photosensitive elements in each of the photosensitive arrays is smaller than a preset gap value.

[0013] A laser radar comprises: a laser emitting module for generating a laser beam and then emitting it to a target area, wherein an object in the target area reflects the laser beam to obtain a reflected beam; and a laser radar receiving system, which adopts the laser radar receiving system as described above.

[0014] Wherein, the spot size of the laser beam reflected by the laser emitting module is adapted to the preset area.

[0015] The embodiments of the present invention have the following beneficial effects:

[0016] The area of ​​the photosensitive array on the photosensitive receiving surface is set to be less than or equal to a preset area value, so that the reflected light spot formed when the reflected light beam of the laser radar is irradiated on the photosensitive receiving array surface can hit all the photosensitive elements in the photosensitive array at the same time. The signals output by each photosensitive element correspond to the same reflected light spot and are therefore correlated. Multiplying these signals can enhance the effective signal and effectively eliminate noise, thereby improving the signal-to-noise ratio of the output signal. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] in:

[0019] Figure 1 is a schematic structural diagram of a first embodiment of a laser radar receiving system provided by the present invention;

[0020] Figure 2 Is the signal of no improvement and Figure 1 A comparison diagram of the output signals of the laser radar receiving system shown;

[0021] Figure 3 is a structural schematic diagram of a second embodiment of a laser radar receiving system provided by the present invention;

[0022] Figure 4 It is a structural schematic diagram of a first embodiment of a photosensitive array in a laser radar receiving system provided by the present invention;

[0023] Figure 5 is a schematic structural diagram of a second embodiment of a photosensitive array in a laser radar receiving system provided by the present invention;

[0024] Figure 6 is a schematic structural diagram of a third embodiment of a photosensitive array in a laser radar receiving system provided by the present invention;

[0025] Figure 7 is a schematic structural diagram of a fourth embodiment of a photosensitive array in a laser radar receiving system provided by the present invention;

[0026] Figure 8 is a schematic structural diagram of a fifth embodiment of a photosensitive array in a laser radar receiving system provided by the present invention;

[0027] Fig. 9 It is a schematic structural diagram of the first embodiment of the laser radar provided by the present invention. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] In the receiving system of the coaxial laser radar, the position of the light spot on the photosensitive receiving array is fixed and is easily affected by the interference light in the environment. When the environmental noise is large, the signal may not be detected normally. Correlation detection is a technology that uses the characteristics of signal correlation and noise randomness to remove noise detection signals through correlation operations.

[0030] In this embodiment, in order to solve the above-mentioned problem, a laser radar receiving system is provided, which can effectively improve the signal-to-noise ratio of the received signal.

[0031] See also Figure 1 , Figure 1It is a structural schematic diagram of the first embodiment of the laser radar receiving system provided by the present invention. The laser radar receiving system 10 is used to receive the reflected light spot of the laser radar. The laser radar receiving system 10 includes a photosensitive receiving array 11. The photosensitive receiving array 11 includes two photosensitive arrays 111 and 112. In other implementation scenarios, the number of photosensitive arrays 111 can be set according to user needs, such as 1, 3, 5, etc. The laser radar receiving system 10 also includes signal processing circuits 12 and 13. The signal processing circuit 12 is set corresponding to the photosensitive array 111, and the signal processing circuit 13 is set corresponding to the photosensitive array 112. When the number of photosensitive arrays included in the photosensitive receiving array 11 is more, the number of signal processing circuits will also increase accordingly to achieve the corresponding setting with the photosensitive array. In other embodiments, multiple photosensitive arrays 112 may correspond to one signal processing circuit 13, that is, one signal processing circuit 13 can be responsible for the signal processing of multiple photosensitive arrays 112.

[0032] The structures of the photosensitive arrays 111 and 112 are the same, so the photosensitive array 111 is used as an example for explanation. The photosensitive array 111 includes 2n photosensitive elements, where n is greater than 1. For example, in this implementation scenario, n=2, and the photosensitive array 111 includes 4 photosensitive elements 1111, 1112, 1113, and 1114, wherein the photosensitive elements 1111 and 1114 are neither in the same row nor in the same column. Figure 1 As shown in , four photosensitive elements 1111, 1112, 1113 and 1114 are arranged in a matrix. The area of ​​the photosensitive array 111 is smaller than the preset area value, so that the reflected light spot of the laser radar can hit all the photosensitive elements in the photosensitive array 111 (photosensitive elements 1111, 1112, 1113 and 1114) at the same time. It should be noted that hitting all the photosensitive elements mentioned in this case means that the light spot can fall on each photosensitive element, which can be that the light spot completely covers all the photosensitive elements, or that the light spot only covers part of the area of ​​the photosensitive element.

[0033] The four photosensitive elements 1111, 1112, 1113 and 1114 are connected to the signal processing circuit 12, and the signal processing circuit 12 is used to perform multiplication operations on the signals output by the four photosensitive elements 1111, 1112, 1113 and 1114. Since the light pulses received by the four photosensitive elements 1111, 1112, 1113 and 1114 correspond to the same reflected light spot, the signals output by the four photosensitive elements 1111, 1112, 1113 and 1114 are correlated. Therefore, when the four signals are multiplied, the effective signals (correlated partial signals) therein will be amplified, while the noises of different sizes (irrelevant partial signals) will be reduced or smoothed, so that the effective signals originally submerged by the noise can be retained and enhanced.

[0034] In this implementation scenario, the four signals can be multiplied in pairs and then the two products can be multiplied to obtain the target signal. In other implementation scenarios, two signals can be selected for multiplication first and then multiplied with the remaining two signals in sequence to obtain the target signal.

[0035] Please refer to Figure 2 , Figure 2 Is the signal of no improvement and Figure 1 The comparison diagram of the output signal of the laser radar receiving system is shown in Figure 2 It can be seen that its signal-to-noise ratio has been greatly improved, which is conducive to identifying effective optical signals from noise, thereby ensuring the accuracy of detection.

[0036] From the above description, it can be seen that in this embodiment, by setting the area of ​​the photosensitive array to be less than or equal to the preset area value, the reflected light spot formed when the reflected light beam of the laser radar is irradiated on the photosensitive receiving array surface can hit all the photosensitive elements in the photosensitive array at the same time. The signals output by each photosensitive element correspond to the same reflected light spot and are therefore correlated. Multiplying these signals can enhance the effective signal and effectively eliminate noise, thereby improving the signal-to-noise ratio of the output signal.

[0037] See also Figure 3 , Figure 3 2 is a schematic diagram of the structure of the second embodiment of the laser radar receiving system provided by the present invention. The laser radar receiving system 20 includes a photosensitive receiving array 21, and the photosensitive receiving array 21 includes a photosensitive array 211. The photosensitive array 211 includes four photosensitive elements 2111, 2112, 2113 and 2114. In this embodiment, the photosensitive elements 2111, 2112, 2113 and 2114 are APDs (Avalanche Photo Diodes), which are highly sensitive detectors that use the avalanche multiplication effect to multiply the photocurrent. In other embodiments, other elements with photoelectric conversion functions may be used, such as SPAD (Single Photon Avalanche Diode), silicon photomultiplier (SiPM, also partially referred to as MPPC detector (multi-pixel photon counter) or other types of photoelectric detectors known to those skilled in the art. The laser radar receiving system 20 also includes a signal processing circuit 22. The signal processing circuit 22 includes four amplifiers 2211, 2212, 2213 and 2214, four low-pass filters 2221, 2222, 2223 and 2224, and a related detection multiplier 223.

[0038] In this implementation scenario, four amplifiers 2211, 2212, 2213 and 2214 are connected to four photosensitive elements 2111, 2112, 2113 and 2114, and four low-pass filters 2221, 2222, 2223 and 2224 are connected to four photosensitive elements 2111, 2112, 2113 and 2114. Specifically, the photosensitive element 2111 is connected to the output end of the amplifier 2211, and the amplifier 2211 amplifies the signal output by the photosensitive element 2111 to obtain an amplified signal. The output end of the amplifier 2211 is connected to the input end of the low-pass filter 2221, and the low-pass filter 2221 filters the amplified signal to obtain a filtered signal. Similarly, the photosensitive element 2112 is connected to the output end of the amplifier 2212, and the output end of the amplifier 2212 is connected to the input end of the low-pass filter 2222. The photosensitive element 2113 is connected to the output end of the amplifier 2213, and the output end of the amplifier 2213 is connected to the input end of the low-pass filter 2223. The photosensitive element 2114 is connected to the output end of the amplifier 2214, and the output end of the amplifier 2214 is connected to the input end of the low-pass filter 2224. The output ends of the low-pass filters 2221, 2222, 2223 and 2224 are connected to the correlation detection multiplier 223. The correlation detection multiplier 223 performs multiplication operation on the signals output by the low-pass filters 2221, 2222, 2223 and 2224, which can enhance the effective signal and effectively eliminate the noise.

[0039] It can be seen from the above description that in this embodiment, the use of an amplifier can enhance the signal strength, thereby enhancing the effective signal, and the use of a low-pass filter can effectively remove high-frequency noise, thereby more effectively improving the signal-to-noise ratio of the target signal. In other embodiments, only a low-pass filter or an amplifier may be provided.

[0040] See also Figure 4 , Figure 4It is a structural schematic diagram of the first embodiment of the photosensitive array in the laser radar receiving system provided by the present invention. The photosensitive array 30 includes four photosensitive elements 31, 32, 33 and 34. The photosensitive elements 31, 32, 33 and 34 are arranged in a matrix, and the photosensitive surface areas of the photosensitive elements 31, 32, 33 and 34 are not completely equal. For example, the photosensitive surface areas of the photosensitive elements 31 and 33 are larger, and the photosensitive surface areas of the photosensitive elements 32 and 34 are smaller. Different photosensitive surface areas have different photosensitivity, that is, for the same reflected light spot, the signals output by the photosensitive elements 31 and 33 and the signals output by the photosensitive elements 32 and 34 have different gains. If the reflected light beam is reflected by a closer target or a target with a high reflectivity, the reflected light beam is stronger, the photosensitive surface areas of the photosensitive elements 32 and 34 are small, and the photosensitivity is weak, and the signal intensity generated by the reflected light beam will not be too high. If the reflected light beam is reflected by a distant target or an object with low reflectivity, the intensity of the reflected light beam is relatively weak, and the photosensitive surface area of ​​the photosensitive elements 31 and 33 is large, and the photosensitivity is relatively strong, so the signal intensity generated by the reflected light beam will not be too low. In another embodiment, the areas of the two diagonal photosensitive elements can be set to be the same, and the areas of the two photosensitive elements in the same row / column can be different.

[0041] In this implementation scenario, regardless of the strength of the reflected light beam, there are at least two photosensitive elements (31 and 33 or 32 and 34) whose output signal strength is moderate. In this way, when the signals output by the photosensitive elements 31, 32, 33 and 34 are output to the signal processing circuit for multiplication, it can effectively avoid the input signal strength being too high or too low, resulting in a low signal-to-noise ratio.

[0042] In this embodiment, the gap d between any two of the photosensitive elements 31, 32, 33 and 34 is less than 0.3 mm, which can effectively concentrate the energy of the reflected light spot. Furthermore, the gap d between the photosensitive elements 31, 32, 33 and 34 is less than 0.1 mm, which can further improve the signal-to-noise ratio.

[0043] From the above description, it can be seen that the photosensitive elements in the photosensitive array in this embodiment have different photosensitive surface areas and thus have different photosensitivity capabilities, so that when the laser radar receiving system where the photosensitive array is located receives reflected light beams with different intensities, there is at least one sampling signal with appropriate gain in the sampling signals generated, which can effectively avoid the input of signals with too high or too low intensity into the processing circuit for multiplication operations, thereby effectively improving the signal-to-noise ratio of the signal.

[0044] See also Figure 5 , Figure 54 is a schematic diagram of the structure of the second embodiment of the photosensitive array in the laser radar receiving system provided by the present invention. The photosensitive array 40 includes 9 photosensitive elements 41, 42, 43, 44, 45, 46, 47, 48 and 49. The 9 photosensitive elements 41, 42, 43, 44, 45, 46, 47, 48 and 49 are arranged in a matrix, and the photosensitive surface areas of the 9 photosensitive elements 41, 42, 43, 44, 45, 46, 47, 48 and 49 are not completely equal. Among them, the photosensitive surface areas of the photosensitive elements 41, 42, 43, 44, 46, 47, 48 and 49 are larger, and the photosensitive surface area of ​​the photosensitive element 45 is smaller. Photosensitive elements 41, 42, 43, 44, 46, 47, 48 and 49 are located at the periphery of the photosensitive array 40. Increasing the photosensitive surface area of ​​the photosensitive elements 41, 42, 43, 44, 46, 47, 48 and 49 can effectively improve the efficiency of the light pulses of the reflected light spots obtained therefrom.

[0045] In addition, in this embodiment, the 9 signals output by the 9 photosensitive elements 41, 42, 43, 44, 45, 46, 47, 48 and 49 are multiplied, which can effectively eliminate noise and enhance the effective signal, thereby improving the signal-to-noise ratio of the output signal.

[0046] From the above description, it can be seen that in this embodiment, the photosensitive area of ​​the photosensitive elements at the periphery of the photosensitive array is relatively large, which can effectively improve the efficiency of the light pulse of the acquired reflected light spot, thereby effectively enhancing the effective signal and improving the signal-to-noise ratio of the output signal.

[0047] See also Figure 6 , Figure 6 : is a schematic diagram of the structure of the third embodiment of the photosensitive array in the laser radar receiving system provided by the present invention. The photosensitive array 50 includes four photosensitive elements 51, 52, 53 and 54. The photosensitive elements 51, 52, 53 and 54 are arranged along the circumferential direction. In this embodiment, the photosensitive elements 51, 52, 53 and 54 arranged along the circumferential direction can be hit by the reflected light spots at the same time to generate correlated signals.

[0048] From the above description, it can be seen that in this embodiment, the photosensitive elements are arranged along the circumferential direction, which can easily be hit by the reflected light spots at the same time. The signals output by each photosensitive element correspond to the same reflected light spot and are therefore correlated, thereby effectively enhancing the effective signal and improving the signal-to-noise ratio of the output signal.

[0049] See also Figure 7 , Figure 7It is a schematic diagram of the structure of the fourth embodiment of the photosensitive array in the laser radar receiving system provided by the present invention. The photosensitive array 60 includes four photosensitive elements 61, 62, 63 and 64. The photosensitive elements 61, 62, 63 and 64 are fan-shaped and arranged circumferentially. The photosensitive array 60 formed by splicing the photosensitive elements 61, 62, 63 and 64 is circular. The centers of the photosensitive elements 61, 62, 63 and 64 are close to each other. In this implementation scenario, the photosensitive surfaces of the photosensitive elements 61, 62, 63 and 64 are fan-shaped. In other implementation scenarios, the photosensitive surfaces can also be other shapes such as triangles, squares, and diamonds.

[0050] In this embodiment, the photosensitive array 60 includes four photosensitive elements 61, 62, 63 and 64 with the same structure. In other implementation scenarios, a photosensitive array may include five, six or even more photosensitive elements with the same or similar structure, and the arcs of these photosensitive elements are located on the same circumference.

[0051] In this embodiment, the photosensitive surface is also fan-shaped, and the photosensitive surfaces of the photosensitive elements 61, 62, 63 and 64 are spliced ​​into a smaller circle, which has a lower requirement on the diameter of the reflected light spot. Even the reflected light spot with a smaller diameter can hit the photosensitive surfaces of the photosensitive elements 61, 62, 63 and 64 at the same time.

[0052] From the above description, it can be seen that in this embodiment, the photosensitive element is fan-shaped and arranged circumferentially, and the photosensitive surface of the photosensitive element is arranged away from the arc side of the fan, which can effectively increase the probability of the reflected light spot hitting the photosensitive surfaces of all photosensitive elements at the same time, reduce the requirements for the diameter of the reflected light spot, and make it less difficult to adjust the position of the reflected light spot on the photosensitive receiving array surface, which can effectively improve work efficiency and reduce work costs.

[0053] See also Figure 8 , Figure 8 It is a schematic diagram of the structure of the fifth embodiment of the photosensitive array in the laser radar receiving system provided by the present invention. The photosensitive array 70 includes 7 photosensitive elements 71, 72, 73, 74 and 75. The photosensitive elements 71, 72, 73, 74 and 75 are fan-shaped and arranged along the circumferential direction. The photosensitive array 70 formed by splicing the photosensitive elements 71, 72, 73, 74 and 75 is circular. The centers of the photosensitive elements 71, 72, 73, 74 and 75 are close to each other. Among them, the photosensitive surface area of ​​the photosensitive elements 72 and 73 is smaller than the photosensitive surface area of ​​the photosensitive elements 71, 74 and 75.

[0054] Regardless of the strength of the reflected light beam, there are at least two photosensitive elements (72 and 73 or 71, 74 and 75) whose output signals have moderate strength. Thus, when the signals output by the photosensitive elements 71, 72, 73, 74 and 75 are output to the signal processing circuit for multiplication, it can effectively avoid the input signal strength being too high or too low, resulting in a low signal-to-noise ratio.

[0055] The photosensitive surface is also fan-shaped. The photosensitive surfaces of the photosensitive elements 71, 72, 73, 74 and 75 are spliced ​​into a smaller circle, which has a lower requirement on the diameter of the reflected light spot. Even a reflected light spot with a smaller diameter can hit the photosensitive surfaces of the photosensitive elements 71, 72, 73, 74 and 75 at the same time.

[0056] From the above description, it can be seen that the photosensitive elements in this embodiment have different photosensitive surface areas and different photosensitivity capabilities, so that when the laser radar receiving system where the photosensitive array is located receives reflected light beams with different intensities, there is at least one sampling signal with appropriate gain in the sampling signals generated, which can effectively avoid the multiplication operation of the signal input processing circuit with too high or too low intensity, and effectively improve the signal-to-noise ratio of the signal. The photosensitive surface of the photosensitive element is set away from the arc side of the fan-shaped, which can effectively increase the probability of the reflected light spot hitting the photosensitive surfaces of all photosensitive elements at the same time, reduce the requirements for the diameter of the reflected light spot, and reduce the difficulty of adjusting the position of the reflected light spot on the photosensitive receiving array surface, which can effectively improve work efficiency and reduce work costs.

[0057] See also Fig. 9 , Fig. 9 FIG. 8 is a schematic diagram of the structure of the first embodiment of the laser radar provided by the present invention. The laser radar 80 provided by the present invention includes a laser emitting module 81 and a laser radar receiving system 82, wherein the laser radar receiving system 82 includes Figure 1 and Figure 3 The laser radar receiving system shown and / or having Figure 4-Figure 8 The photosensitive array shown.

[0058] like Figure 8 As shown, the laser emission module 81 is used to produce a laser beam and then emit it to the target area. The objects in the target area reflect the laser beam to obtain a reflected beam. Further, the laser radar 80 also includes a collimator 83, a perforated reflector 84, a galvanometer 85 and a receiving lens group 86. The laser emitted by the laser emission module 81 passes through the collimator 83 and becomes parallel light and is emitted. It passes through the perforated reflector 84 and is emitted to the galvanometer 85. After being reflected by the galvanometer 85, it is emitted to the target area. The objects in the target area reflect the laser beam to obtain a reflected beam. After being reflected by the galvanometer 85, the reflected beam is emitted to the reflective surface of the perforated reflector 84. The perforated reflector 84 reflects the reflected beam to the receiving lens group 86. After being focused by the receiving lens group 86, the reflected beam is emitted to the laser radar receiving system 82.

[0059] According to the above description, the laser radar receiving system 82 includes a photosensitive receiving array 821, and the photosensitive receiving array 821 includes at least one photosensitive array 8211, each photosensitive array includes 2n photosensitive elements (n is greater than 1), and at least two of the 2n photosensitive elements are neither in the same row nor in the same column; the area of ​​the photosensitive array 8211 is less than or equal to the preset area value, so that the reflected light spot formed when the reflected light beam of the laser radar 80 is irradiated on the photosensitive receiving array 821 can simultaneously hit all the photosensitive elements in a photosensitive array 8211. Furthermore, the gap between the photosensitive elements in the photosensitive array is less than the preset gap value, so that the reflected light spot formed when the reflected light beam of the laser radar 80 is irradiated on the photosensitive receiving array 821 can simultaneously hit all the photosensitive elements in a photosensitive array 8211. Specifically, when the gap between two adjacent photosensitive elements is less than 0.1 mm, the spot diameter is required to be greater than 0.1 mm; when the gap between two adjacent photosensitive elements is greater than 0.3 mm, the spot diameter is required to be greater than 0.55 mm.

[0060] The laser radar receiving system 82 also includes at least one signal processing circuit, which is arranged in a one-to-one correspondence with at least one photosensitive array 8211. Each signal processing circuit is connected to 2n photosensitive elements in the corresponding photosensitive array 8211, and is used to multiply the signals output by the 2n photosensitive elements in the corresponding photosensitive array 8211 to obtain a target signal and output the target signal.

[0061] The 2n photosensitive elements in each photosensitive array are arranged in a matrix.

[0062] The 2n photosensitive elements in each photosensitive array are arranged along the circumferential direction.

[0063] The photosensitive elements are in a fan shape, and the centers of the photosensitive elements in the same photosensitive array are close to each other.

[0064] Each photosensitive array includes at least four photosensitive elements with the same structure, and the arcs of the photosensitive elements are located on the same circumference.

[0065] The photosensitive surface areas of the 2n photosensitive elements in each photosensitive array are not completely equal.

[0066] Each signal processing circuit includes: 2n amplifiers, which are connected to the 2n photosensitive elements in a one-to-one correspondence and are used to amplify the signals output by the 2n photosensitive elements.

[0067] Each signal processing circuit further includes: 2n low-pass filters, which are connected to the 2n photosensitive elements in a one-to-one correspondence and are used to filter the signals output by the 2n photosensitive elements.

[0068] From the above description, it can be seen that the area of ​​the photosensitive array of the photosensitive receiving array surface of the laser radar receiving system of the laser radar in this embodiment is less than or equal to the preset area value, so that the reflected light spot formed when the reflected light beam of the laser radar is irradiated on the photosensitive receiving array surface can hit all the photosensitive elements in the photosensitive array at the same time. The signals output by each photosensitive element correspond to the same reflected light spot and are therefore correlated. Multiplying these signals can enhance the effective signal and effectively eliminate noise, thereby improving the signal-to-noise ratio of the output signal.

[0069] Different from the prior art, the area of ​​the photosensitive array of the photosensitive receiving array surface in the present invention is less than or equal to a preset area value, so that the reflected light spot formed when the reflected light beam of the laser radar is irradiated on the photosensitive receiving array surface can hit all the photosensitive elements in the photosensitive array at the same time. The signals output by each photosensitive element correspond to the same reflected light spot and are therefore correlated. Multiplying these signals can enhance the effective signal and effectively eliminate noise, thereby improving the signal-to-noise ratio of the output signal.

[0070] The above disclosure is only the preferred embodiment of the present invention, which certainly cannot be used to limit the scope of the present invention. Therefore, equivalent changes made according to the claims of the present invention are still within the scope of the present invention.

Claims

1. A laser radar receiving system, characterized in that: The laser radar receiving system is used to receive the reflected light beam of the laser radar; the laser radar receiving system includes: A photosensitive receiving array, comprising at least one photosensitive array, each of which comprises 2n photosensitive elements, where n is greater than 1, at least two of the 2n photosensitive elements are neither in the same row nor in the same column, and the photosensitive surface areas of the 2n photosensitive elements in each photosensitive array are not completely equal; the area of ​​the photosensitive array is less than or equal to a preset area value, so that the reflected light spot formed when the reflected light beam of the laser radar is irradiated on the photosensitive receiving array can hit all the photosensitive elements in one photosensitive array at the same time; At least one signal processing circuit is arranged in a one-to-one correspondence with the at least one photosensitive array, and each of the signal processing circuits is connected to the 2n photosensitive elements in the corresponding photosensitive array, and is used to multiply the signals output by the 2n photosensitive elements in the corresponding photosensitive array to obtain a target signal, and output the target signal. Each of the signal processing circuits includes: 2n amplifiers, connected in a one-to-one correspondence with the 2n photosensitive elements, and are used to amplify the signals output by the 2n photosensitive elements; and / or 2n low-pass filters, connected in a one-to-one correspondence with the 2n photosensitive elements, and are used to filter the signals output by the 2n photosensitive elements.

2. The laser radar receiving system according to claim 1, characterized in that: The 2n photosensitive elements in each photosensitive array are arranged in a matrix.

3. The laser radar receiving system according to claim 1, characterized in that: The 2n photosensitive elements in each photosensitive array are arranged along the circumferential direction.

4. The laser radar receiving system according to claim 3, characterized in that: The shape of the photosensitive elements is fan-shaped, and the centers of the photosensitive elements in the same photosensitive array are close to each other.

5. The laser radar receiving system according to claim 4, characterized in that: Each of the photosensitive arrays includes at least four photosensitive elements with the same structure, and the arcs of the photosensitive elements are located on the same circumference.

6. The laser radar receiving system according to claim 1, characterized in that: The gap between two adjacent photosensitive elements in each of the photosensitive arrays is smaller than a preset gap value.

7. A laser radar, characterized in that: include: A laser emission module, used for generating a laser beam and then emitting it to a target area, wherein an object in the target area reflects the laser beam to obtain a reflected beam; and The laser radar receiving system adopts the laser radar receiving system as described in any one of claims 1 to 6.

8. The laser radar according to claim 7, characterized in that: The spot size of the laser beam reflected by the laser emitting module is adapted to the preset area.

Images