Laser detector, detection method and laser radar

Abstract

The invention provides a laser detector, a detection method and a laser radar. The laser detector comprises a plurality of light detection units, an output switch set, a control module, at least one output channel and a received signal processing module. Each light detection unit in the plurality of light detection units is selectively connected with an output channel in the at least one output channel through an output switch in the output switch set; the control module is used for controlling the output switch to select an output channel in the at least one output channel, so that the light detection unit is connected with the selected output channel or disconnected from the at least one output channel; and the received signal processing module is used for receiving the incident light signals detected by the plurality of light detection units through the at least one output channel, processing the incident light signals and providing output signals. The application can more flexibly adapt to different application requirements.

Description

Technical Field

[0001] The present application relates to the field of laser radar, and in particular to a laser detector, a detection method and a laser radar. Background Art

[0002] Faced with the complex and ever-changing real-world vehicle driving environment, high-level autonomous driving functions have put forward higher requirements for the perception and detection capabilities of on-board LiDAR: including but not limited to longer detection distances, no blind spots in close-range detection distances, and differentiation of object reflectivity at different distances. Currently, LiDAR generally uses TOF (Time of Fight) technology. A pulsed laser is emitted in the direction of the target, and the reflected light that encounters the object will be received by the detector. By measuring the flight time of the light pulse between the radar and the target and the intensity and shape of the reflected echo, information on whether there is an object in the target direction, the distance from the object to the radar, and the reflectivity of the object's surface can be obtained.

[0003] Laser detectors are the core components of TOF solutions, which determine the detection efficiency, detection resolution and detection dynamic range of the photoelectric conversion link. Existing laser detectors still have room for improvement. Summary of the invention

[0004] The present application provides a laser detector, a detection method and a laser radar that can more flexibly adapt to different application requirements.

[0005] In a first aspect, the present application provides a laser detector, comprising a plurality of light detection units, an output switch set, a control module, at least one output channel and a received signal processing module;

[0006] Each of the plurality of light detection units is selectively connected to an output channel of the at least one output channel through an output switch in the output switch set;

[0007] The control module is used to control the output switch to select an output channel among the at least one output channel, so that the light detection unit is connected to the selected output channel or disconnected from the at least one output channel;

[0008] The received signal processing module is used to receive the incident light signals detected by the multiple light detection units through the at least one output channel, process the incident light signals and provide output signals.

[0009] Optionally, the number of the at least one output channel is at least two;

[0010] The control module is further used to control the output switch to select one of the at least two output channels for connection.

[0011] Optionally, the control module is specifically used to obtain output signal-to-noise ratios of the multiple light detection units in at least the previous detection, and disconnect the light detection unit whose output signal-to-noise ratio is lower than a first threshold from the at least one output channel in this detection.

[0012] Optionally, the control module is used to determine at least some of the light detection units located at tolerance reserved positions among the multiple light detection units, and disconnect at least some of the light detection units located at the tolerance reserved positions from the at least one output channel in this detection.

[0013] Optionally, the control module is used to obtain output signal-to-noise ratios of the multiple light detection units at a detection frequency lower than a detection frequency, and determine the light detection unit located at the tolerance reserved position according to the output signal-to-noise ratios of the multiple light detection units.

[0014] Optionally, the control module is used to acquire an imaging area of ​​the emission light spot on the multiple light detection units at a detection frequency lower than the detection frequency, and disconnect at least part of the light detection units located outside the imaging area from the at least one output channel.

[0015] Optionally, the control module is further used to determine the offset of the imaging area of ​​the emission light spot during the detection process, and adjust the connection between some of the multiple light detection units and the at least one output channel according to the offset.

[0016] Optionally, the control module is specifically used to disconnect the light detection unit that is moved out of the imaging area due to the offset from the at least one output channel, and to connect the light detection unit that is moved into the imaging area due to the offset to an output channel of the at least one output channel.

[0017] Optionally, the control module is also used to determine the light detection units corresponding to each detection channel that are affected by crosstalk from other channels exceeding a second threshold, and to disconnect at least part of the determined light detection units from the at least one output channel when detecting in the channel where they are located.

[0018] Optionally, at least two light detection units among the plurality of light detection units are connected to one of the at least two different output channels through a same output switch.

[0019] Optionally, the at least two light detection units are connected to another output channel of the at least two different output channels through different output switches respectively; or,

[0020] The at least two light detection units are selected from the at least two different output channels through the same output switch so as to be all connected to the same output channel each time.

[0021] Optionally, the at least two light detection units are a first block among the plurality of light detection units, and the first block includes light detection units located in a central area of ​​the plurality of light detection units; or,

[0022] The at least two light detection units are a second block among the plurality of light detection units, and the second block includes light detection units located in a peripheral area of ​​the plurality of light detection units.

[0023] Optionally, the laser detector further comprises an input switch set, and each of the plurality of light detection units selectively connects to one of at least two different bias voltages through an input switch in the input switch set;

[0024] The control module is further configured to control the input switch to select one of the at least two different bias voltages, so that the light detection unit is connected to the selected bias voltage.

[0025] Optionally, the at least two different bias voltages include a first bias voltage and a second bias voltage, and the second bias voltage is higher than the first bias voltage; the at least one output channel includes a first output channel and a second output channel;

[0026] For at least part of the multiple light detection units, the control module is used to control the input switch and the output switch in two adjacent detections so that at least part of them switches from connecting the first bias voltage and the first output channel to connecting the second bias voltage and the second output channel.

[0027] Optionally, the plurality of light detection units include SiPM or SPAD arrays.

[0028] Optionally, the laser detector further comprises a storage module for storing connection configuration information between the plurality of light detection units and the output switch set.

[0029] In a second aspect, the present application provides a detection method, applied to any one of the laser detectors, characterized in that it includes:

[0030] Controlling each output switch in the output switch set so that at least some of the plurality of light detection units are connected to or disconnected from an output channel in the at least one output channel;

[0031] receiving incident light signals detected by the plurality of light detection units through the at least one output channel;

[0032] The incident light signal is processed and an output signal is provided.

[0033] In a third aspect, the present application provides a laser radar, comprising:

[0034] A laser transmitter for emitting a laser beam, and any laser detector described above.

[0035] In an embodiment of the present application, an output switch set is provided in the laser detector, and each light detection unit selects to connect to at least one output channel through an output switch in the output switch set, so that the outputs of the multiple light detection units can be reconfigured, making it convenient to determine which signals in the multiple light detection units participate in the output and which signals do not participate in the output according to different scenarios and requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 is a schematic diagram of an embodiment of a laser detector in the present application;

[0037] Figure 2 is a schematic diagram of the relationship between each light detection unit, an output switch set and two output channels in one embodiment;

[0038] Figure 3 is a schematic diagram of an embodiment of a laser detector in the present application;

[0039] Figure 4 It is a schematic diagram of the structure of a SiPM;

[0040] Figure 5 It is a schematic diagram of the structure of a SPAD array;

[0041] Figure 6 It is a schematic diagram of an embodiment of the positional relationship between the emission spot imaging and the overall phase of each light detection unit in the laser radar;

[0042] Fig. 7A is a schematic diagram of an embodiment of the positional relationship between an imaging area of ​​an emission spot in a laser radar and a second tolerance area;

[0043] Figure 7B is a schematic diagram of another embodiment of the positional relationship between the imaging area of ​​the emission spot in the laser radar and the second tolerance area;

[0044] Figure 7C yes Fig. 7A A schematic diagram of the movement of the imaging area of ​​the emission spot in the laser radar shown;

[0045] Figure 8is a schematic diagram of another embodiment of a laser detector of the present application;

[0046] Fig. 9 is a schematic diagram of an embodiment of the detection method of the present application;

[0047] Fig.10 It is a schematic diagram of an embodiment of a laser radar in an embodiment of the present application. DETAILED DESCRIPTION

[0048] The embodiments of the present application will be described in more detail below with reference to the accompanying drawings. Although the embodiments of the present application are shown in the accompanying drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to make the present application more thorough and complete, and to fully convey the scope of the present application to those skilled in the art.

[0049] The terms used in this application are for the purpose of describing specific embodiments only and are not intended to limit this application. The singular forms of "a", "said" and "the" used in this application and the appended claims are also intended to include plural forms unless the context clearly indicates other meanings. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more associated listed items.

[0050] It should be understood that although the terms "first", "second", "third", etc. may be used in this application to describe various information, this information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of this application, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0051] Laser radar is a radar system that emits laser beams to detect the position, speed and other characteristic quantities of the target. One of its working principles is to emit a laser beam to the target detection area, and then calculate the time difference between the received reflected echo and the emitted laser beam, which is the flight time of the laser beam. The laser radar calculates the distance, direction and other parameters of the object reflecting the echo based on the flight time, thereby detecting the external environment. Laser radar generally includes a transceiver module and a processing module. The laser transmitter in the transceiver module converts the electrical pulse into a light pulse and emits it, and then the light pulse reflected from the target is restored to an electrical pulse signal through the laser detector, and the processing module calculates relevant information based on the electrical pulse signal. Optionally, the laser radar may also include a scanning module (such as a MEMS galvanometer, a rotating mirror, a mechanical rotating platform, etc.) to change the emission direction of the emitted laser beam to achieve scanning of the laser beam within a certain field of view. In the example where the optical paths of the echo laser and the emitted laser are coaxial, the echo laser returns along the path of the scanning module-transceiver module and is received by the laser detector in the transceiver module.

[0052] like Figure 1 As shown, Figure 1 It is a schematic diagram of an embodiment of the laser detector in the present application. The laser detector 10 includes a plurality of light detection units 11, an output switch set 12, at least one output channel 13, a received signal processing module 14 and a control module 15. Each of the plurality of light detection units 11 is selectively connected with an output channel in the at least one output channel 13 through an output switch in the output switch set 12. The control module is used to control the output switch to select an output channel in the at least one output channel, so that the light detection unit is connected to the selected output channel or disconnected from the at least one output channel. The received signal processing module 14 is used to receive the incident light signal detected by the plurality of light detection units through the at least one output channel, process the incident light signal and provide an output signal.

[0053] Optionally, the light detection unit may include a single photon avalanche diode (SPAD), a SPAD array or a silicon photomultiplier (SiPM), wherein the SiPM is a device composed of several spads. The single-point SPAD operates in Geiger mode with a large gain. Once triggered by a single photon, a large current signal is generated. Therefore, the photoelectric conversion efficiency is high, and the excitation of a single photon can be detected. It is suitable for weak light measurement, such as detecting echoes with low reflectivity at a long distance.

[0054] In some examples, the number of output channels may be only one, and an output switch is provided between each light detection unit and the output channel. For each light detection unit, the control module may determine whether the signal of the light detection unit participates in the output by connecting and disconnecting the switch between the light detection unit and the output channel. Optionally, at least two light detection units may be connected to the output channel through the same switch, so that the control module may determine whether the signals of the at least two light detection units participate in the output by only one switch.

[0055] In some examples, the number of output channels may be at least two, each light detection unit is connected to a different output channel through a different switch, and the control module connects to the output channel by turning on the switch corresponding to the selected output channel; or each light detection unit is connected to one of the at least two output channels through the same switch. Figure 2 As shown, Figure 2 Schematic diagram of the relationship between each light detection unit, an output switch set and two output channels in one embodiment. The laser detector includes a light detection unit 111, a light detection unit 112, a first output channel 131, a second output channel 132 and an output switch set, wherein the light detection unit 111 is connected to the first output channel 131 and the second output channel 132 respectively through switches 121 and 122 in the output switch set, and the light detection unit 112 is connected to the first output channel 131 and the second output channel 132 respectively through switches 123 and 124 in the output switch set. The receiving signal processing module includes a first receiving circuit 141 connected to the first output channel 131, and includes a second receiving circuit 142 connected to the second output channel.

[0056] In some examples, at least two of the plurality of light detection units are connected to one of the at least two output channels through the same input switch. In practical applications, there is a high probability that some of the plurality of light detection units need to be connected to the same output channel in various situations. Connecting these light detection units to the same output channel through only one switch can simplify the switch layout and improve the control efficiency.

[0057] Alternatively, as another optional method, this part of the detection units can also be connected to a configurable branch, and the configurable branch has switches to each detection unit and each output. By switching the output through the configurable branch, the output channels of multiple detection units can be set in batches by one switch, thereby realizing batch configuration of the outputs of multiple detection units in one switch, improving control efficiency and design flexibility.

[0058] For example, Figure 3 As shown, Figure 3It is a schematic diagram of an embodiment of the laser detector in the present application. The multiple light detection units include a first block 113, wherein the first block includes at least two light detection units. The first block 113 is connected to the first output channel through a switch 125, so that when the switch 125 is turned on, the signals of all the light detection units in the first block 113 are merged and output through the first output channel. Optionally, the first block 113 is also connected to the second output channel through a switch 126, so that when the switch 126 is turned on, the signals of all the light detection units in the first block 113 are merged and output through the second output channel. Alternatively, different light detection units in the first block 113 may be connected to the second output channel through different switches, respectively, so as to individually control whether the light detection unit is merged into the second output channel for output by individually turning on and off the switch between each light detection unit and the second output channel.

[0059] As an optional implementation, the first block 113 can be connected to the first output channel or the second output channel respectively through a single-pole double-throw switch.

[0060] In some examples, the binning can be implemented by silicon photomultiplier (SiPM) binning. Figure 4 As shown, Figure 4 This is a schematic diagram of the structure of a SiPM. SiPM 40 is composed of multiple single-point SPAD micro-units 41 connected to the first output channel through a switch under the same bias voltage V1 input, so that when the switch is turned on, the multiple single-point SPAD micro-units 41 are connected in parallel to generate an output O1 output from the first output channel, wherein switches 127 and 128 are respectively provided between the output O1 and the first output channel and the second output channel. The output O1 is a composite signal triggered by multiple SPADs, which characterizes the relationship between the number of SPADs triggered in the SiPM phase and time, so SiPM is also called MPPC (Multi-Pixel Photon Counter). The output of SiPM directly reflects the light intensity information of the detected light signal.

[0061] In some examples, the binning can be achieved by binning the outputs of an off-the-shelf SPAD array. Figure 5 As shown, Figure 5 Schematic diagram of the structure of a SPAD array. The SPAD array 50 is an array composed of single-point SPADs 51. Under the same bias voltage V2 input, each single-point SPAD has an independent output O2 and can only respond to single-photon triggering. Figure 5As shown, all outputs O2 of the SPAD array can be combined to implement SiPM, and switches 127 and 128 are provided between all combined outputs O2 and the first output channel and the second output channel, respectively. Alternatively, the output of the existing SPAD array can be divided into at least two blocks, wherein the output of each block is combined and connected to different output channels through different switches.

[0062] In an embodiment of the present application, an output switch set is provided in the laser detector, and each light detection unit selects to connect to at least one output channel through an output switch in the output switch set, so that the outputs of the multiple light detection units can be reconfigured, making it convenient to determine which signals in the multiple light detection units participate in the output and which signals do not participate in the output according to different scenarios and requirements.

[0063] In some examples, the shape, arrangement and number of each light detection unit are adapted to the optomechanical system of the laser radar to obtain all the reflected energy that can be received by the receiving aperture of the laser radar. However, in order to reduce the transmission crosstalk between different channels of the laser radar, the receiving field divergence angle of the optomechanical system is designed to be larger than the divergence angle of the emission light spot, so that the image of the emission light spot on the overall phase plane of each light detection unit is smaller than the size of the overall phase plane. Moreover, the design of the overall phase plane of each light detection unit will also leave enough margin for the tolerance between assembly and structure. Figure 6 As shown, Figure 6 1 is a schematic diagram of an embodiment of the positional relationship between the emission light spot imaging and the overall phase plane of each light detection unit in the laser radar. Each light detection unit includes a light detection unit located in the imaging area 602 of the emission light spot and a light detection unit located in the first tolerance area 601 surrounding the imaging area 602 of the emission light spot, so as to ensure that the imaging of the emission light spot can be received by the overall phase plane 600 of each light detection unit.

[0064] Most of the first tolerance area 601 cannot receive effective echo signals, but can receive noise signals and other stray signals, resulting in a very poor signal-to-noise ratio of the effective echo in the first tolerance area 601, which reduces the signal-to-noise ratio of the overall output signal of the laser detector, making the detection capability of the laser detector weaker. In the embodiment of the present application, since each optical detection unit is connected to the output channel through an output switch, the control module can improve the signal-to-noise ratio of the overall output signal of the laser detector and improve the detection capability of the laser detector by turning off at least some of the optical detection units in the first tolerance area 601.

[0065] Among them, there are multiple methods for determining the position of the light detection unit to be turned off. Optionally, the control module can obtain the output signal-to-noise ratio of the multiple light detection units in at least the previous detection, and disconnect the light detection unit whose output signal-to-noise ratio is lower than the first threshold from all output channels in this detection. Alternatively, the control module is used to determine the light detection unit located at the tolerance reserved position among the multiple light detection units, and disconnect the light detection unit located at the tolerance reserved position from all output channels in this detection. Optionally, the control module is used to obtain the output signal-to-noise ratio of the multiple light detection units at a detection frequency lower than the detection frequency, and determine the light detection unit located at the tolerance reserved position according to the output signal-to-noise ratio of the multiple light detection units. For example, the control module can periodically enter the self-test mode autonomously or enter the self-test mode in response to a trigger.

[0066] In the self-check mode, the control module can scan the output signal-to-noise ratio of each light detection unit, detect the light detection unit whose output signal-to-noise ratio is lower than the signal-to-noise ratio threshold, and disconnect the self-detected light detection unit from all output channels. For example, the correlation between the detection signal of each light detection unit and the laser emission is checked respectively, and when the correlation is lower than the coherence threshold, it is determined that the output signal-to-noise ratio of the light detection unit is lower than the signal-to-noise ratio threshold. Alternatively, in the self-check mode, the control module can scan the signal intensity of each light detection unit, detect the light detection unit whose intensity is lower than the intensity threshold, and disconnect the self-detected light detection unit from all output channels. Alternatively, the control module can connect the output of each light detection unit row by row or one by one to an output channel, determine the distribution position of the effective light detection unit by determining the maximum output amplitude position, and then disconnect the remaining light detection units other than the effective light detection unit from all output channels. Alternatively, in the self-check mode, the control module determines the distribution position of the effective light detection unit by judging the imaging area of ​​the emission spot of the laser radar on the overall phase plane of each light detection unit through the optical imaging area, and then disconnects at least part of the light detection units other than the effective light detection unit from all output channels.

[0067] As an optional implementation, the control module may include a detection circuit, wherein the detection circuit includes an ADC or a TDC, and the detection circuit realizes a self-checking function by cooperating with a SiPM or a SPAD array to synthesize a signal.

[0068] It is understood that the SiPM or SPAD array synthesized signal may include one or more channels. It is understood that at least one output signal of the SiPM or SPAD array synthesized signal is output to a built-in detection circuit ADC or TDC.

[0069] It can be understood that the control module in the present application may also include a flexible configuration mode. For example, the control module can implement partition configuration through switch switching actions, and the present application does not impose any restrictions on this.

[0070] In existing laser detectors, once the SiPM phase plane design and the optomechanical system adaptation design are determined, subsequent iterative design changes require re-customization of the SiPM when the size or shape of the SiPM phase plane is adjusted. This will increase the iterative development cost of LIDAR products and extend the iterative development cycle. In this application, each light detection unit selects to connect at least one output channel through the output switch concentrated in the output switch, and can freely configure the size and shape of the phase plane of the SiPM effective output to adapt to different SiPM phase plane design requirements, avoid re-customization of the SiPM during iterative design, improve the flexibility and compatibility of the design, reduce the iterative development cost, and shorten the iterative development cycle.

[0071] In some examples, in a laser radar with a moving scanning component, the optical machine (including the moving scanning component) may creep during long-term use, that is, during long-term operation, the imaging area of ​​the emission light spot will gradually deviate from the original position. This may be due to the different flight times of reflected echoes at different distances, which causes the imaging area 602 of the emission light spot to shift under the action of the scanning motion. Therefore, optionally, the laser detector in this example also introduces an additional walk-off tolerance in the design of the overall phase plane 600 of each light detection unit to form a second tolerance area 603. The shape and position of the second tolerance area 603 are related to the movement mode of the moving scanning component and the shape of the imaging area of ​​the emission light spot. In some examples, such as Fig. 7A As shown, Fig. 7A FIG. 6 is a schematic diagram of an embodiment of the positional relationship between the imaging area of ​​the emission light spot and the second tolerance area in the laser radar. The imaging area 602 of the emission light spot is rectangular, and the second tolerance area 603 is strip-shaped and is located on one side adjacent to the imaging area 602 of the emission light spot. Figure 7B As shown, Figure 7B 602 is a schematic diagram of another embodiment of the positional relationship between the imaging area of ​​the emission light spot and the second tolerance area in the laser radar. The imaging area 602 of the emission light spot is circular, and the second tolerance area 603 is crescent-shaped and is located on one side adjacent to the imaging area 602 of the emission light spot.

[0072] like Figure 7C As shown, Figure 7C yes Fig. 7ASchematic diagram of the movement of the imaging area of ​​the emission spot in the laser radar shown. During the displacement process of the imaging area 602 of the emission spot, the imaging area 602 of the emission spot gradually moves toward the second tolerance area 603, so that at least part of the light detection units originally located in the second tolerance area 603 become located in the imaging area 602, and the light detection units moved out of the imaging area 602 become located in the second tolerance area 603.

[0073] Optionally, each light detection unit located in the second tolerance area 603 is connected to the same output channel through different switches. The control module is also used to control the disconnection and connection between each light detection unit in the second tolerance area 603 and the output channel as the imaging area of ​​the emission light spot moves. For example, since the second tolerance area 603 does not receive a valid signal, resulting in a low signal-to-noise ratio, the control module controls the light detection signal in the second tolerance area 603 to be disconnected from all output channels; as the imaging area of ​​the emission light spot moves, the control module is used to turn on the switch between the light detection unit moved from the second tolerance area 603 into the imaging area of ​​the emission light spot and one of the output channels, and disconnect the switch between the light detection unit moved from the imaging area of ​​the emission light spot into the second tolerance area 603 and all output channels.

[0074] Compared with traditional laser detectors, in which the SiPM detection capability is reduced due to the deviation of the imaging area of ​​the emission light spot, and the imaging area may even be offset outside the SiPM phase plane, each light detection unit in the present application selects to connect to at least one output channel through the output switch concentrated in the output switch, and controls the connection and disconnection of each light detection unit with the output channel by coordinating the movement of the imaging area, which can change the effective output area and perform compensation, thereby further improving the signal-to-noise ratio of the received signal.

[0075] Among them, the position of the second tolerance area 603 can be preset before leaving the factory, or, after leaving the factory, the laser detector can determine the current imaging area of ​​the emission light spot by scanning the distribution of the light detection unit that detects effective reception, and compare it with the initial imaging area of ​​the emission light spot to determine the offset position of the imaging area of ​​the emission light spot.

[0076] In some examples, in a laser radar with multi-channel detection, crosstalk may occur between channels. The control module can also identify the light detection unit in each channel that is subject to greater crosstalk from other channels, and disconnect the light detection unit with greater crosstalk from all output channels when detecting in that channel to shut down the output of these light detection units, thereby reducing the intensity of crosstalk between channels and comprehensively improving the receiving detection performance of the laser detector.

[0077] In the above examples, each light detection unit selectively connects at least one output channel through an output switch in the output switch set. Optionally, the laser detector further includes an input switch set, and each light detection unit selectively connects one of at least two different bias voltages through an input switch in the input switch set. For example, Figure 8 As shown, Figure 8 is a schematic diagram of another embodiment of the laser detector of the present application. Figure 1 The laser detector shown is different in that the laser detector further includes an input switch set 16, and each of the plurality of light detection units 11 selectively connects to an output channel in at least one output channel through an output switch in the output switch set 16. The control module 15 is used to control the input switch to select one of the at least two different bias voltages, so that the light detection unit is connected to the selected bias voltage.

[0078] Specifically, at least one switch is provided between each light detection unit and each of the at least two different bias voltages. In some examples, each light detection unit is connected to the first bias voltage through different switches. In some examples, at least two of the multiple light detection units are connected to one of the at least two different bias voltages through the same input switch. In practical applications, there is a high probability that some of the multiple light detection units need to be connected to the same bias voltage in various situations. Connecting these light detection units to the same bias voltage through only one switch can simplify the switch layout and improve the control efficiency.

[0079] In this example, by providing an input switch set in the laser detector, each light detection unit selects and connects one of the bias voltages of at least two different bias voltages through the input switch in the input switch set, and different light detection units in the multiple light detection units can be conveniently set to have different input bias voltages, wherein the light detection unit providing a higher bias voltage has a higher photoelectric conversion efficiency and a larger gain, which is suitable for weaker light measurement, such as echoes at a longer distance or echoes with a lower reflectivity; the light detection unit providing a lower bias voltage has a lower photoelectric conversion efficiency and a smaller gain, which is suitable for strong light measurement, such as echoes at a closer distance or echoes with a higher reflectivity. In this way, by setting different light detection units with different bias voltages, different detection efficiencies can be taken into account and a higher detection dynamic range can be achieved; it also means that under the same laser emission power, the laser detector in this application can achieve a longer detection distance at night and a direct detection capability that is closer to the optical signal-to-noise ratio during the day. In addition, the intensity of strong light can be better identified and distinguished, thereby better realizing the distinction of reflectivity, especially the distinction of reflectivity at close range. There is no need to introduce the low-energy emission in the traditional short-range ranging solution, which can save the energy consumption of single-point ranging, simplify the transmission and reception timing design, and simplify the laser emission circuit design.

[0080] Moreover, each light detection unit can selectively connect one of at least two different bias voltages through the input switch concentrated in the input switch, so the bias voltage of each light detection unit can be flexibly set. Compared with the solution in which light detection units in different partitions are fixedly connected to different bias voltages, it can avoid the light detection units in high bias partitions from being saturated under strong signals reflected at close range (including leading signals during high-power transmission in coaxial systems), thereby causing loss of detection capability and generating additional power consumption. It can also avoid the problem of more light detection units in low bias partitions affecting the ability to detect weak signals at long distances, and avoid the problem of limited dynamic range due to fewer light detection units in low bias partitions.

[0081] Optionally, the control module can control all the light detection units connected to the same bias voltage to select the same output channel for output. Optionally, the control module can control some of the light detection units connected to the same bias voltage to select the first output channel for output and some of the light detection units to select the second output channel for output. Optionally, the control module can control some or all of the light detection units connected to the first bias voltage and some or all of the light detection units connected to the second bias voltage to select the same output channel for output.

[0082] Optionally, the laser detector in the present application further includes a storage module for storing connection configuration information between the plurality of light detection units and the input switch set. Specifically, the storage module may include a non-volatile storage medium and a digital communication configuration interface to configure and store output control configuration information of each light detection unit or each block.

[0083] The present application also provides a detection method, which is applied to any of the above-mentioned laser detectors. Fig. 9 As shown, Fig. 9 900 is a schematic diagram of an embodiment of a detection method of the present application. The method 900 includes:

[0084] Step S901, controlling each output switch in the output switch set so that at least part of the plurality of light detection units are connected to or disconnected from an output channel in the at least one output channel respectively;

[0085] Step S902, receiving incident light signals detected by the plurality of light detection units through the at least one output channel;

[0086] Step S903: Process the incident light signal and provide an output signal.

[0087] The present application also provides a laser radar, such as Fig.10 As shown, Fig.10 is a schematic diagram of an embodiment of a laser radar in an embodiment of the present application. The laser radar 1 includes a laser emitter 2 for emitting a laser beam, and the laser detector 10 described above. It can be understood that, as an optional embodiment, the laser radar may also include a scanning component, wherein the scanning component may be, for example, a galvanometer, a rotating mirror, a mechanical rotating platform, etc. The present application does not limit whether the laser radar includes a scanning component.

[0088] The embodiments of the present application have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The selection of terms used herein is intended to best explain the principles of the embodiments, practical applications, or improvements to the technology in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. A laser detector, characterized in that: It includes a plurality of light detection units, an output switch set, a control module, at least one output channel and a receiving signal processing module; Each of the plurality of light detection units is selectively connected to an output channel of the at least one output channel through an output switch in the output switch set; The control module is used to control the output switch to select an output channel among the at least one output channel, so that the light detection unit is connected to the selected output channel or disconnected from the at least one output channel; The received signal processing module is used to receive the incident light signals detected by the multiple light detection units through the at least one output channel, process the incident light signals and provide output signals.

2. The laser detector according to claim 1, characterized in that: The number of the at least one output channel is at least two; The control module is further used to control the output switch to select one of the at least two output channels for connection.

3. The laser detector according to claim 1, characterized in that: The control module is specifically used to obtain the output signal-to-noise ratio of the multiple light detection units in at least the previous detection, and disconnect the light detection unit whose output signal-to-noise ratio is lower than the first threshold from the at least one output channel in this detection.

4. The laser detector according to claim 1, characterized in that: The control module is used to determine at least some of the light detection units located at tolerance reserved positions among the multiple light detection units, and disconnect at least some of the light detection units located at the tolerance reserved positions from the at least one output channel in this detection.

5. The laser detector according to claim 4, characterized in that: The control module is used to obtain the output signal-to-noise ratio of the multiple light detection units at a detection frequency lower than the detection frequency, and determine the light detection unit located at the tolerance reserved position according to the output signal-to-noise ratio of the multiple light detection units.

6. The laser detector according to claim 4, characterized in that: The control module is used to acquire an imaging area of ​​the emission light spot on the plurality of light detection units at a detection frequency lower than a detection frequency, and disconnect at least part of the light detection units located outside the imaging area from the at least one output channel.

7. The laser detector according to claim 1, characterized in that: The control module is further used to determine the offset of the imaging area of ​​the emission light spot during the detection process, and to adjust the connection between some of the plurality of light detection units and the at least one output channel according to the offset.

8. The laser detector according to claim 7, characterized in that: The control module is specifically used to disconnect the light detection unit that is moved out of the imaging area due to the offset from the at least one output channel, and to connect the light detection unit that is moved into the imaging area due to the offset to an output channel of the at least one output channel.

9. The laser detector according to claim 1, characterized in that: The control module is also used to determine the light detection units corresponding to each detection channel that are affected by crosstalk from other channels exceeding a second threshold, and to disconnect at least part of the determined light detection units from the at least one output channel when detecting in the channel where they are located.

10. The laser detector according to any one of claims 1 to 9, characterized in that: At least two of the plurality of light detection units are connected to one of the at least two different output channels through a same output switch.

11. The laser detector according to claim 10, characterized in that: The at least two light detection units are respectively connected to another output channel of the at least two different output channels through different output switches; or, The at least two light detection units are selected from the at least two different output channels through the same output switch so as to be all connected to the same output channel each time.

12. The laser detector according to claim 10, characterized in that: The at least two light detection units are a first block among the plurality of light detection units, and the first block includes light detection units located in a central area of ​​the plurality of light detection units; or, The at least two light detection units are a second block among the plurality of light detection units, and the second block includes light detection units located in a peripheral area of ​​the plurality of light detection units.

13. A detection method, applied to the laser detector according to any one of claims 1 to 12, characterized in that: include: Controlling each output switch in the output switch set so that at least some of the plurality of light detection units are connected to or disconnected from an output channel in the at least one output channel; receiving incident light signals detected by the plurality of light detection units through the at least one output channel; The incident light signal is processed and an output signal is provided.

14. A laser radar, characterized in that: include: A laser transmitter for emitting a laser beam, and a laser detector as claimed in any one of claims 1 to 12.

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