Laser receiving device and laser radar

Abstract

The invention discloses a laser receiving device and a laser radar, the laser receiving device comprises an optical receiver, a power supply control circuit and a conditioning amplification circuit, the optical receiver is used for receiving an echo signal and outputting a receiving electric signal, the power supply control circuit is connected with the optical receiver, and the conditioning amplification circuit is connected with the optical receiver. The power supply control circuit is used for controlling bias voltage of the optical receiver to be increased to a saturation bias value from an initial bias value at a preset change rate and controlling the bias voltage to be smaller than a breakdown voltage value before a first preset moment, the initial bias value is smaller than the breakdown voltage value, and the saturation bias value is larger than the breakdown voltage value; and the conditioning amplification circuit is connected with the optical receiver and is used for adjusting the pulse width of the received electric signal output by the optical receiver. According to the design, short-distance detection of the laser radar can be realized.

Description

Technical Field

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

[0002] LiDAR is increasingly being used in application scenarios such as unmanned driving. LiDAR includes a light transmitting module and a light receiving module. The light transmitting module is used to emit outgoing laser, and the light receiving module is used to receive echo laser.

[0003] A portion of the outgoing laser emitted by the optical transmitting module does not reach the target object to form a detection echo laser, but is directly reflected back by the window of the laser radar to form a stray echo laser. The stray echo laser will excite the optical receiver of the optical receiving module. Since the optical receiver of the optical receiving module needs a certain recovery time after receiving the stray echo laser, and the optical receiving module cannot detect the close-range detection echo laser within the recovery time, the laser radar has a certain range of detection blind spots, which makes the laser radar unable to detect close-range target objects. Summary of the invention

[0004] The embodiments of the present application provide a laser receiving device and a laser radar, which can solve the problem in the related art that the optical receiving module cannot detect the close-range detection echo laser within the recovery time, resulting in a certain range of detection blind spots in the laser radar, making it impossible for the laser radar to detect close-range target objects.

[0005] In the first aspect, an embodiment of the present application provides a laser receiving device; the laser receiving device includes an optical receiver, a power control circuit and a conditioning amplifier circuit; the optical receiver is used to receive an echo signal and output a received electrical signal; the power control circuit is connected to the optical receiver, and the power control circuit is used to control the bias voltage of the optical receiver to increase from a starting bias value to a saturation bias value at a preset change rate, and is less than a breakdown voltage value before a first preset moment, the starting bias value is less than the breakdown voltage value, and the saturation bias value is greater than the breakdown voltage value; the conditioning amplifier circuit is connected to the optical receiver, and is used to amplify and adjust the pulse width of the received electrical signal output by the optical receiver.

[0006] Based on the laser receiving device of the embodiment of the present application, the bias voltage of the optical receiver is controlled by designing a power control circuit to increase to a saturation bias value at a preset rate of change, and at the same time, it is less than the breakdown voltage value before the first preset moment; before the first preset moment, the optical receiver is not in a working state and will not be excited by the received optical pre-echo; after the first preset moment, the bias voltage of the optical receiver is greater than the breakdown voltage value and increases rapidly at a preset rate of change, the optical receiver quickly recovers the working state, quickly responds to the echo light signal at a close distance and outputs the received electrical signal. Since during the rapid increase of the bias voltage of the optical receiver, the output received electrical signal also contains a strong pre-electromotive signal, the pre-electromotive signal is too strong and overlaps with the detection electrical signal, making it difficult to accurately sample the detection electrical signal and output the detection result; by designing a conditioning amplifier circuit to perform pulse width shaping processing on the received electrical signal, the pre-electromotive signal and the detection electrical signal are separated from each other, so that the detection electrical signal can be sampled and measured to output accurate detection results, so as to ensure the detection stability and accuracy of the laser radar.

[0007] In a second aspect, an embodiment of the present application provides a laser radar, which includes a laser emitting device and the above-mentioned laser receiving device, and the laser emitting device is used to emit a transmission signal.

[0008] Based on the laser radar in the embodiment of the present application, with the above-mentioned laser receiving device, close-range detection of the laser radar can be achieved, and the detection stability and accuracy of the laser radar can be ensured. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] In order to more clearly illustrate the embodiments of the present application 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 application. For those skilled in the art, other drawings can be obtained based on these drawings without paying any creative work.

[0010] Figure 1 This is a schematic diagram of the structural framework of a laser receiving device in one embodiment of the present application;

[0011] Figure 2 A schematic diagram of a waveform of a bias voltage of an optical receiver in an embodiment of the present application;

[0012] Figure 3 A waveform diagram of a received electrical signal output by a conditioning and amplifying circuit in one embodiment of the present application;

[0013] Figure 4 This is a schematic diagram of the circuit structure of a power control circuit in one embodiment of the present application;

[0014] Figure 5A schematic diagram of the circuit structure of a power control circuit in another embodiment of the present application;

[0015] Figure 6 A schematic diagram of the circuit structure of a power control circuit in another embodiment of the present application;

[0016] Figure 7 A schematic diagram of the circuit structure of a power control circuit in another embodiment of the present application;

[0017] Figure 8 This is a circuit structure diagram of a light source control circuit in another embodiment of the present application;

[0018] Fig. 9 A schematic diagram of the circuit structure of a conditioning amplifier circuit in an embodiment of the present application;

[0019] Fig.10 A schematic diagram of the structural framework of a laser receiving device in another embodiment of the present application;

[0020] Fig.11 This is a schematic diagram of the circuit structure of a temperature drift compensation circuit in one embodiment of the present application;

[0021] Fig.12 Schematic diagram of the circuit structure of a temperature drift compensation circuit in another embodiment of the present application;

[0022] Fig.13 This is a schematic diagram of a circuit structure in which a filter circuit and a temperature drift compensation circuit are connected in series in one embodiment of the present application;

[0023] Fig.14 This is a schematic diagram of the circuit structure of a laser receiving device in one embodiment of the present application;

[0024] Fig.15 This is a schematic diagram of a circuit structure in which a filter circuit and a temperature drift compensation circuit are connected in parallel in one embodiment of the present application;

[0025] Fig.16 This is a schematic diagram of the circuit structure of a laser receiving device in another embodiment of the present application;

[0026] Fig.17 This is a schematic diagram of the framework structure of a laser radar in one embodiment of the present application.

[0027] 1. Laser receiving device; 10. Optical receiver; 20. Power supply control circuit; K1. First switch switching unit; K2. Second switch switching unit; PHV. First voltage source; NHV. Second voltage source; R1. First resistor; C1. First capacitor; R2. Second resistor; C2. Second capacitor; 30. Conditioning amplifier circuit; TIA. Amplifier; C4. Coupling capacitor; R6. Sixth resistor; R7. Seventh resistor; R8. Eighth resistor; R9. Ninth resistor; VDD. DC voltage source; 40. Temperature drift compensation circuit; R3. Third resistor; 41. First compensation resistor; R4. Fourth resistor; NTC1. First thermistor; 42. Second compensation resistor; R5. Fifth resistor; NTC2. Second thermistor; 50. Filter circuit; C3. Filter capacitor; 2. Laser radar; 21. Laser emitting device. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0029] Laser radar is increasingly being used in application scenarios such as unmanned driving. Laser radar includes a light emitting device and a light receiving device, wherein the light emitting device is used to emit an outgoing laser and the light receiving device is used to receive an echo laser.

[0030] Part of the outgoing laser emitted by the optical transmitting device is reflected or scattered by the optical components, structural components, etc. in the laser radar and then directly returns to the optical receiving device. This part of the returned stray light is the optical precursor echo. The optical precursor echo is received by the optical receiver of the optical receiving device and then outputs the optical precursor conductive signal. Since the optical receiver of the optical receiving device receives and responds to the optical precursor echo and then outputs the optical precursor conductive signal, the optical precursor conductive signal has a long tailing area, and the detection electrical signal output by the optical receiving device during the time period of the tailing area will overlap with the optical precursor conductive signal, and it is impossible to distinguish and detect the detection electrical signal, and further, it is impossible to obtain the reception time of the detection echo returned by the target object at a close distance after reflecting the outgoing laser, resulting in a detection blind area within a certain distance range for the laser radar, which makes it impossible for the laser radar to detect close-range target objects, resulting in a near-field blind area.

[0031] The near-field blind zone range of the laser radar depends on the recovery time of the optical receiver of the optical receiving device. The "recovery time" is the time required for the optical receiver to recover to the initial working state after being excited by the optical precursor echo. The recovery time is related to the device characteristics of the optical receiver.

[0032] On the other hand, the near-field blind area of ​​the laser radar depends on the intensity of the optical precursor echo. The greater the intensity of the optical precursor echo, the greater the current of the optical precursor electric signal output by the optical receiver and the longer the tailing area, which has a greater impact on the close-range detection electric signal. Among them, the intensity of the optical precursor echo is related to the internal optical path and structural design of the laser radar; for example, if there are many optical elements set on the internal optical path of the laser radar, the angle of the window is improper, and there are many reflections or scatterings of the structural parts arranged along the optical path, the intensity of the optical precursor echo will increase. The intensity of the optical precursor echo is also related to the application scenario of the laser radar; for example, the laser radar is set in the cabin, and the laser radar's outgoing laser passes through the window piece and then needs to pass through the light-transmitting window of the cockpit. The outgoing laser is reflected or scattered on the light-transmitting window again, and then returns to enter the interior of the laser radar; at this time, compared to the scenario where the laser radar is set outside the cabin and the laser radar's outgoing laser passes through the window piece for direct detection, this scenario where the laser radar is installed in the cabin will obviously receive more optical precursor echoes, and the corresponding optical precursor electrical signal output by the optical receiver has a higher amplitude and a longer tailing area, which makes the optical precursor electrical signal block the detection electrical signal for a longer area, resulting in a larger near-field blind area for the laser radar.

[0033] To solve the above technical problems, please refer to Figure 1-Figure 3 As shown, the first aspect of the present application proposes a laser receiving device 1, which can realize a laser radar 2 (such as Fig.17 Close range detection of the

[0034] The laser receiving device 1 includes an optical receiver 10, a power control circuit 20 and a conditioning amplifier circuit 30. The optical receiver 10 is used to receive an echo optical signal and output a received electrical signal. The power control circuit 20 is connected to the optical receiver 10, and is used to control the bias voltage Vbias of the optical receiver 10 to increase from the initial bias value V0 to the saturation bias value V2 at a preset change rate. The power control circuit 20 also controls the bias voltage Vbias to be less than the breakdown voltage value Vbr before the first preset time T1, wherein the initial bias value V0 is less than the breakdown voltage value Vbr, and the saturation bias value V2 is greater than the breakdown voltage value Vbr. The conditioning amplifier circuit 30 is connected to the optical receiver 10, and is used to amplify and adjust the pulse width of the received electrical signal output by the optical receiver 10.

[0035] The following combination Figure 1-Figure 16 The specific structure of the laser receiving device 1 is introduced in detail.

[0036] like Figure 1-Figure 3 As shown, an embodiment of the present application provides a laser receiving device 1 , which includes an optical receiver 10 , a power control circuit 20 and a conditioning amplifier circuit 30 .

[0037] The optical receiver 10 is a device in the laser receiving device 1 that can convert an optical signal into an electrical signal.

[0038] The optical receiver 10 is used to receive the echo optical signal, and convert the received echo optical signal into an electrical output induction signal, and the output induction signal is the received electrical signal. Among them, the echo optical signal may include a detection echo and an optical precursor echo. The detection echo is an optical signal that the outgoing laser of the laser radar 2 is reflected by the target object and returns to the optical receiver 10, and the optical precursor echo is an optical signal that the outgoing laser of the laser radar 2 is reflected or scattered internally and returns to the optical receiver 10. After receiving the echo optical signal, the optical receiver 10 outputs a received electrical signal, and the received electrical signal may include a detection electrical signal and an optical precursor electrical signal. The detection electrical signal is an electrical signal output after the detection echo is received by the optical receiver 10, and the optical precursor electrical signal is an electrical signal output after the optical precursor echo is received by the optical receiver 10.

[0039] It should be noted that the optical receiver 10 is a photoelectric sensor, and the photoelectric sensor can be a current output type photoelectric sensor or a voltage output type photoelectric sensor. If the photoelectric sensor is a current output type photoelectric sensor, the above-mentioned received electrical signal is a current signal; if the photoelectric sensor is a voltage output type photoelectric sensor, the above-mentioned received electrical signal is a voltage signal. Specifically, the photoelectric sensor can be a highly sensitive detector, such as one or more combinations of APD (avalanche diode), SPAD (single photo avalanche diode), and SiPM (silicon photomultiplier). For example, taking the optical receiver 10 as a silicon photomultiplier tube as an exemplary illustration, the silicon photomultiplier tube includes a plurality of micro units connected in parallel, and each micro unit includes an avalanche diode and a quenching resistor. When a bias voltage (generally a reverse bias voltage of tens of volts) is applied to both ends of the silicon photomultiplier tube, the depletion layer of the avalanche diode in each micro unit has a very strong electric field. At this time, if the echo light signal hits the avalanche diode, the photons in the echo light signal will undergo Compton scattering with the electron-hole pairs in the semiconductor, knocking out electrons or holes. The high-energy electrons and holes are then accelerated in the electric field to knock out a large number of secondary electrons and holes, i.e., an avalanche effect occurs. At this time, the output current of each micro unit suddenly increases to output the received electrical signal.

[0040] like Figure 1-Figure 3 As shown, the power control circuit 20 is a circuit structure used in the laser receiving device 1 to control the bias voltage Vbias at both ends of the optical receiver 10. The specific circuit structure of the power control circuit 20 will be described in detail below.

[0041] The power control circuit 20 is connected to the optical receiver 10 , and is used to control the bias voltage Vbias of the optical receiver 10 to increase from an initial bias value V0 to a saturation bias value V2 at a preset change rate.

[0042] It should be noted that the "bias voltage Vbias" is understood as the working voltage applied to the optical receiver 10. Taking the optical receiver 10 composed of SiPM as an example, since the optical receiver 10 works in Geiger mode, the voltage across the optical receiver 10 is reversed in the working state, so it is called the bias voltage Vbias. The bias voltage Vbias is the voltage difference between the anode and the cathode of the optical receiver 10. The moment when the corresponding optical transmitter of the optical receiver 10 emits the outgoing laser is the starting moment of the optical receiver 10, and the bias voltage Vbias at this time is the starting bias value V0. The bias voltage Vbias of the optical receiver 10 starts from the starting bias value V0 and rises rapidly to the saturation bias value V2 at a preset change rate. The saturation bias value V2 is a preset value, which is the bias voltage of the optical receiver 10 to maintain the working state during the detection process. The selection of the saturation bias value V2 is related to the gain of the received electrical signal output after the echo light signal is converted by the optical receiver 10; the larger the bias voltage Vbias, the greater the gain of the received electrical signal. The bias voltage Vbias may be increased from the initial bias value V0 to the saturation bias value V2 at a single preset change rate. The bias voltage Vbias may also be increased from the initial bias value V0 to the saturation bias value V2 at different preset change rates.

[0043] The power control circuit 20 controls the bias voltage Vbias to be less than the breakdown voltage value Vbr before the first preset moment T1, that is, the optical receiver 10 is not in the working state, and even if the optical receiver 10 receives the echo light signal, it cannot be stimulated to output the received electrical signal. The power control circuit 20 controls the bias voltage Vbias to be greater than the breakdown voltage value Vbr after the first preset moment T1, that is, the optical receiver 10 resumes the working state, and the optical receiver 10 outputs the received electrical signal after receiving the echo signal. In this way, the optical precursor echo can be effectively suppressed from stimulating the optical receiver 10 to generate the optical precursor electrical signal. At the same time, at the moment after the first preset moment T1, the real detection echo can also be effectively detected, avoiding the influence of the optical precursor echo on the near-field detection. Among them, the starting bias value V0<breakdown voltage value Vbr<saturation bias value V2. The first preset moment T1 is the receiving moment of the optical precursor echo. As can be seen from the above, the optical precursor echo is the outgoing laser reflected or scattered inside the laser radar 2 and then returned to the optical receiver 10, so the flight distance of the optical precursor echo is the optical path length inside the laser radar 2, so a certain reception time of the optical precursor echo can be obtained, that is, the first preset time T1, and the echo light signal received before the first preset time T1 is the optical precursor echo. The first preset time T1 can be obtained by actual measurement, calibration or simulation.

[0044] The bias voltage Vbias of the optical receiver 10 increases rapidly at a preset rate of change, and can quickly restore the bias voltage Vbias to the saturation bias value V2 after the first preset time T1. As can be seen from the foregoing, the higher the value of the bias voltage Vbias, the greater the gain of the optical receiver 10. The rapid recovery of the bias voltage Vbias of the optical receiver 10 can quickly restore the detection capability of the laser radar 2 for weak-intensity detection echoes, such as the detection capability of the laser radar 2 for low-reflectivity objects.

[0045] like Figure 1-Figure 3 As shown, the conditioning amplifier circuit 30 is a circuit structure in the laser receiving device 1 for amplifying and pulse width shaping the received electrical signal output by the optical receiver 10. When the power control circuit 20 controls the bias voltage Vbias to increase from the initial bias value V0 to the saturation bias value V2, due to the rapid charging and discharging of the internal capacitor of the optical receiver 10, the optical receiver 10 will still output an electrical pre-conductivity signal even if no photon is received. The received electrical signal may include one or more of the detection electrical signal, the optical pre-conductivity signal and the electrical pre-conductivity signal. The amplitude of the electrical pre-conductivity signal changes with the rising speed of the bias voltage Vbias applied by the power control circuit 20 to both ends of the optical receiver 10. The greater the preset change rate of the bias voltage Vbias, the greater the amplitude of the electrical pre-conductivity signal. As mentioned above, the bias voltage Vbias of the optical receiver 10 recovers quickly, the preset change rate is large, and the amplitude of the electrical pre-conductivity signal is also correspondingly large. It can be understood that the detection electrical signal converted by the optical receiver 10 from the received detection echo is weaker than the electrical precursor signal, and there is even a difference in magnitude. The waveform of the electrical precursor signal obscures the waveform of the detection electrical signal, resulting in the inability to accurately identify the detection electrical signal and sample it, thereby resulting in poor detection performance of the laser radar 2.

[0046] In order to eliminate the problem that the bias voltage Vbias at both ends of the optical receiver 10 is quickly increased by the power control circuit 20, resulting in an excessively large electrical preamble signal output by the optical receiver 10, which affects the detection performance of the laser radar 2. The conditioning amplifier circuit 30 is connected to the optical receiver 10, and the conditioning amplifier circuit 30 is used to amplify the received electrical signal output by the optical receiver 10 and adjust the pulse width. It should be noted that, if Figure 3 As shown, before the conditioning amplifier circuit 30 amplifies and performs pulse width shaping on the received electrical signal, the electrical pre-conducting signal is as follows: Figure 3 As shown in A, the received electrical signal is Figure 3 As shown in C in the figure, at this time, the pre-conducting signal and the received signal overlap for the most part, and the detection signal in the received signal cannot be distinguished, resulting in an inability to obtain accurate ranging results after the back-end sampling step. After the conditioning amplifier circuit 30 amplifies and shapes the pulse width of the received signal, it compresses the pulse width of the bias signal, and the received signal is as shown in FIG. Figure 3 As shown in B, at this time, the pre-electrical conductive signal and the received electrical signal are separated from each other, so that the detection electrical signal in the received electrical signal can be distinguished, and an accurate ranging result can be obtained after the back-end sampling step.

[0047] Based on the laser receiving device 1 of the embodiment of the present application, the power supply control circuit 20 is designed to control the bias voltage Vbias of the optical receiver 10 to increase from the initial bias value V0 to the saturation bias value V2 at a preset change rate, and at the same time control the bias voltage Vbias to be less than the breakdown voltage value Vbr before the first preset moment T1; before the first preset moment T1, the optical receiver 10 is not in a working state and will not be excited by the received optical precursor echo; after the first preset moment T1, the bias voltage Vbias of the optical receiver 10 is greater than the breakdown voltage value Vbr and increases rapidly at a preset change rate, the optical receiver 10 quickly resumes the working state, quickly responds to the echo light signal at a close distance and outputs the received electrical signal. Since the bias voltage Vbias of the optical receiver 10 increases rapidly, the output received electrical signal also contains a very strong electrical preamble signal. The electrical preamble signal is too strong and overlaps with the detection electrical signal, making it difficult to accurately sample the detection electrical signal and output the detection result. By designing a conditioning amplifier circuit 30 to amplify and shape the pulse width of the electrical preamble signal, the electrical preamble signal and the detection electrical signal are separated from each other, so that the detection electrical signal can be sampled and measured to output accurate detection results, thereby ensuring the detection stability and accuracy of the laser radar 2.

[0048] like Figure 4-Figure 8 As shown, an embodiment of the present application provides a laser receiving device 1, and a power control circuit 20 of the laser receiving device 1 includes a power module and a control module. The power module is connected to the anode of the optical receiver 10 through the switch switching module, and / or, the power module is connected to the cathode of the optical receiver 10 through the switch switching module. The control module is connected to the switch switching module, and the control module is used to control the switch switching module to be in a first switching state before the second preset time T2, and the control module is also used to control the switch switching module to be in a second switching state after the second preset time T2; the second preset time T2 is between the start time T0 and the first preset time T1.

[0049] The control module controls the switch switching module to be in a first switching state before the second preset time T2, and the power module is not connected to the anode and / or cathode of the optical receiver 10. At this time, the bias voltage Vbias of the optical receiver 10 maintains the initial bias value V0; the control module controls the switch switching module to be in a second switching state after the second preset time T2, and the power module is connected to the anode and / or cathode of the optical receiver 10. At this time, the bias voltage Vbias of the optical receiver 10 starts to increase until it reaches the saturation bias value V2.

[0050] The bias voltage Vbias of the optical receiver 10 is less than the breakdown voltage value Vbr before the first preset time T1, and is greater than the breakdown voltage value Vbr after the first preset time T1, and the breakdown voltage value Vbr is greater than the starting bias value V0. The bias voltage Vbias of the optical receiver 10 cannot change instantaneously and needs to be gradually increased; therefore, the switching state of the switch switching module is changed at the second preset time T2, and the bias voltage Vbias of the optical receiver 10 is controlled to start increasing. In the time period from the second preset time T2 to the first preset time T1, although the bias voltage Vbias starts to increase from the starting bias value V0, it always remains less than the breakdown voltage value Vbr in this time period; in the time period after the first preset time T1, the bias voltage Vbias continues to increase until it reaches the saturation bias value V2, and can always remain greater than the breakdown voltage value Vbr in this time period.

[0051] The specific implementation methods of adjusting the bias voltage Vbias at both ends of the optical receiver 10 through the switch module, the power module and the control module may be but are not limited to the following implementation methods.

[0052] like Figure 4 As shown, in one embodiment, the power module includes a first voltage source PHV; the switch switching module includes a first switch switching unit K1; the first voltage source PHV is connected to the cathode of the optical receiver 10 through the first switch switching unit K1. Specifically, the first connection end of the first switch switching unit K1 is connected to the cathode of the optical receiver 10, the second connection end of the first switch switching unit K1 is connected to the first voltage source PHV, and the controlled end of the first switch switching unit K1 is connected to the control module. The anode of the optical receiver 10 is grounded to keep the anode of the optical receiver 10 at a constant voltage. Of course, as Figure 5 As shown, the power supply module further includes a second voltage source NHV, and the anode of the optical receiver 10 can also be connected to the second voltage source NHV, and the second voltage source NHV can provide a constant negative high voltage.

[0053] When the first connection end of the first switch switching unit K1 is not connected to the second connection end of the first switch switching unit K1, the switch switching module is in the first switching state. When the first connection end of the first switch switching unit K1 is connected to the second connection end of the first switch switching unit K1, the switch switching module is in the second switching state.

[0054] It should be noted that the first voltage source PHV is a high voltage positive power supply. The first switch switching unit K1 includes at least one switch tube, which can be but is not limited to a triode, a field effect tube or a MOS driver. Before the second preset time T2, the first switch switching unit K1 maintains the first switching state, the first connection end of the first switch switching unit K1 and the second connection end of the first switch switching unit K1 are not conducting, the cathode voltage of the optical receiver 10 is the initial cathode voltage V0n, and the anode voltage of the optical receiver 10 is fixed to Vp. At this time, the bias voltage Vbias of the optical receiver 10 is (Vp-V0n). At the second preset time T2, the control module sends a switch control signal to the first switch switching unit K1, so that the switch switching module switches from the first switching state to the second switching state, and at this time, the first connection end of the first switch switching unit K1 and the second connection end of the first switch switching unit K1 are conducting. After being turned on and after the second preset time T2, the cathode voltage of the optical receiver 10 begins to increase, the anode voltage is still Vp, the voltage difference between the two poles of the optical receiver 10 also increases, and the bias voltage Vbias increases rapidly; until the cathode voltage of the optical receiver 10 increases to the positive high voltage of the first voltage source PHV and remains stable, at which time the bias voltage Vbias of the optical receiver 10 also reaches the saturation bias value V2. The control module controls the state of the first switch switching unit K1 at the second preset time T2 to control the bias voltage Vbias of the optical receiver 10.

[0055] The power control circuit 20 also includes a first resistor R1 and a first capacitor C1. The first end of the first resistor R1 is connected to the cathode of the optical receiver 10, and the second end of the first resistor R1 is connected to the first connection end of the first switch switching unit K1. The first plate of the first capacitor C1 is connected to the first end of the first resistor R1, and the second plate of the first capacitor C1 is grounded. When the first connection end and the second connection end of the first switch switching unit K1 are connected, the first resistor R1 and the first capacitor C1 form an RC filter circuit, which can shape and smooth the rising edge of the voltage signal output by the first voltage source PHV.

[0056] It should be noted that, in the link connected to the cathode of the optical receiver 10, the parameters of the first voltage source PHV and the first switch switching unit K1 determine the rising speed of the cathode voltage of the optical receiver 10, and the parameters of the first resistor R1 and the first capacitor C1 further affect the rising edge of the cathode voltage of the optical receiver 10. By setting the parameters of the first resistor R1 and the first capacitor C1, the edge rise time of the voltage signal output from the first voltage source PHV to the cathode of the optical receiver 10 can be adjusted to a few nanoseconds, and its steep rising edge can be used to suppress the ultra-strong optical precursor electric signal generated by the optical precursor echo, while ensuring that the receiving capacity of the optical receiver 10 can be quickly restored, thereby minimizing the blind area range of the detection blind area of ​​the laser radar 2.

[0057] The power control circuit 20 also includes a second resistor R2 and a second capacitor C2. The first end of the second resistor R2 is connected to the anode of the optical receiver 10, and the second end of the second resistor R2 is connected to the second voltage source NHV; the first plate of the second capacitor C2 is connected to the second end of the second resistor R2, and the second plate of the second capacitor C2 is grounded. The second capacitor C2 is a filter capacitor at the load end of the second voltage source NHV, and filters the voltage signal output by the second voltage source NHV to ensure that the voltage signal transmitted to the anode of the optical receiver 10 is low noise. The second resistor R2 is a readout resistor of the optical receiver 10, and converts the current signal output by the optical receiver 10 after photoelectric conversion into a voltage signal.

[0058] like Figure 6 As shown, in one embodiment, the power supply module includes a second voltage source NHV; the switch switching module includes a second switch switching unit K2; the second voltage source NHV is connected to the anode of the optical receiver 10 through the second switch switching unit K2. Specifically, the first connection end of the second switch switching unit K2 is connected to the anode of the optical receiver 10, the second connection end of the second switch switching unit K2 is connected to the second voltage source NHV, and the controlled end of the second switch switching unit K2 is connected to the control module. The cathode of the optical receiver 10 is grounded to keep the cathode of the optical receiver 10 at a constant voltage. Of course, as Figure 7 As shown, the power supply module further includes a first voltage source PHV, and the cathode of the optical receiver 10 can also be connected to the first voltage source PHV, and the first voltage source PHV can provide a constant positive high voltage.

[0059] When the first connection end of the second switch switching unit K2 is not connected to the second connection end of the second switch switching unit K2, the switch switching module is in the above-mentioned first switching state. When the first connection end of the second switch switching unit K2 is connected to the second connection end of the second switch switching unit K2, the switch switching module is in the above-mentioned second switching state.

[0060] It should be noted that the second voltage source NHV is a high voltage negative power supply. The second switch switching unit K2 includes at least one switch tube, which can be but is not limited to a triode, a field effect tube or a MOS driver. Before the second preset time T2, the second switch switching unit K2 maintains the first switching state, the first connection end of the second switch switching unit K2 and the second connection end of the second switch switching unit K2 are not conducting, the anode voltage of the optical receiver 10 is the initial anode voltage V0p, and the cathode voltage of the optical receiver 10 is fixed to Vn, and the bias voltage Vbias of the optical receiver 10 is (V0p-Vn). At the second preset time T2, the control module sends a switch control signal to the second switch switching unit K2, so that the switch switching module switches from the first switching state to the second switching state, and at this time, the first connection end of the second switch switching unit K2 and the second connection end of the second switch switching unit K2 are conducting. After being turned on and after the second preset time T2, the anode voltage of the optical receiver 10 begins to increase, the cathode voltage is still Vn, the voltage difference between the two poles of the optical receiver 10 also increases, and the bias voltage Vbias increases rapidly; until the anode voltage of the optical receiver 10 increases to the negative high voltage of the second voltage source NHV and remains stable, at which time the bias voltage Vbias of the optical receiver 10 also reaches the saturation bias value V2. The control module controls the state of the second switch switching unit K2 at the second preset time T2 to control the bias voltage Vbias of the optical receiver 10.

[0061] The power control circuit 20 also includes a second resistor R2 and a second capacitor C2. The first end of the second resistor R2 is connected to the anode of the optical receiver 10, and the second end of the second resistor R2 is connected to the first connection end of the second switch switching unit K2. The first plate of the second capacitor C2 is connected to the second end of the second resistor R2, and the second plate of the second capacitor C2 is grounded. When the first connection section and the second connection section of the second switch switching unit K2 are connected, the second resistor R2 and the second capacitor C2 form an RC filter circuit, which can shape and smooth the falling edge of the voltage signal output by the second voltage source NHV.

[0062] As mentioned above, in the link connected to the anode of the optical receiver 10, in addition to the parameters of the second voltage source NHV and the second switch switching unit K2 determining the falling speed of the anode voltage of the optical receiver 10, the parameters of the second resistor R2 and the second capacitor C2 also further affect the falling edge of the anode voltage of the optical receiver 10. By setting the parameters of the second resistor R2 and the second capacitor C2, the edge falling time of the voltage signal output from the second voltage source NHV to the anode of the optical receiver 10 can be adjusted to a few nanoseconds, and its steep falling edge can be used to suppress the ultra-strong photoprecursor electric signal generated by the photoprecursor echo, while ensuring that the receiving ability of the optical receiver 10 can be quickly restored, thereby shortening the blind area range of the detection blind area of ​​the laser radar 2 to the greatest extent. In addition, the second resistor R2 is the readout resistor of the optical receiver 10, which converts the current signal output by the optical receiver 10 after photoelectric conversion into a voltage signal.

[0063] The power control circuit 20 also includes a first capacitor C1. The first plate of the first capacitor C1 is connected to the cathode of the optical receiver 10, and the second plate of the first capacitor C1 is grounded. The first capacitor C1 is a filter capacitor at the load end of the first voltage source PHV, and filters the voltage signal output by the first voltage source PHV to ensure that the voltage signal transmitted to the cathode of the optical receiver 10 is low noise.

[0064] like Figure 8 As shown, in one embodiment, the power supply module includes a first voltage source PHV and a second voltage source NHV; and the switch switching module includes a first switch switching unit K1 and a second switch switching unit K2; the first voltage source PHV is connected to the cathode of the optical receiver 10 through the first switch switching unit K1, and the second voltage source NHV is connected to the anode of the optical receiver 10 through the second switch switching unit K2. Specifically, the first connection end of the first switch switching unit K1 is connected to the cathode of the optical receiver 10, the second connection end of the first switch switching unit K1 is connected to the first voltage source PHV, and the controlled end of the first switch switching unit K1 is connected to the control module; the first connection end of the second switch switching unit K2 is connected to the anode of the optical receiver 10, the second connection end of the second switch switching unit K2 is connected to the second voltage source NHV, and the controlled end of the second switch switching unit K2 is connected to the control module. Among them, the first voltage source PHV is a high-voltage positive power supply, and the second voltage source NHV is a high-voltage negative power supply. The switching states of the first switch switching unit K1 and the second switch switching unit K2 are the same as those in the above examples, and will not be repeated here.

[0065] At the second preset time T2, the control module sends a switch control signal to the first switch switching unit K1 and / or the second switch switching unit K2 to control the on / off state of the first switch switching unit K1 and / or the second switch switching unit K2, so as to achieve the adjustment of at least one of the anode voltage of the optical receiver 10 and the cathode voltage of the optical receiver 10, thereby adjusting the bias voltage Vbias at both ends of the optical receiver 10. When any one of the breakdown voltage value Vbr and the saturation bias value V2 of the optical receiver 10 is high, the wide voltage output range of the commonly used switch switching unit is at most 30V, and the cathode of the optical receiver 10 is connected to a high-voltage positive power supply and the anode is connected to a high-voltage negative power supply to obtain the bias voltage Vbias of the optical receiver 10 that meets the working requirements.

[0066] The power control circuit 20 also includes a first resistor R1, a first capacitor C1, a second resistor R2, and a second capacitor C2. The first end of the first resistor R1 is connected to the cathode of the optical receiver 10, and the second end of the first resistor R1 is connected to the first connection end of the first switch switching unit K1. The first plate of the first capacitor C1 is connected to the first end of the first resistor R1, and the second plate of the first capacitor C1 is grounded. By setting the parameters of the first resistor R1 and the first capacitor C1, the edge rise time of the voltage signal output by the first voltage source PHV to the cathode of the optical receiver 10 can be adjusted to a few nanoseconds. The first end of the second resistor R2 is connected to the anode of the optical receiver 10, and the second end of the second resistor R2 is connected to the first end of the second switch switching unit K2. The first plate of the second capacitor C2 is connected to the second end of the second resistor R2, and the second plate of the second capacitor C2 is grounded. By setting the parameters of the second resistor R2 and the second capacitor C2, the edge fall time of the voltage signal output by the second voltage source NHV to the anode of the optical receiver 10 can be adjusted to a few nanoseconds.

[0067] like Fig. 9 As shown, the embodiment of the present application provides a laser receiving device 1, and the conditioning amplifier circuit 30 of the laser receiving device 1 includes a coupling capacitor C4 and an amplifier TIA; the first plate of the coupling capacitor C4 is connected to the optical receiver 10 for inputting the received electrical signal; the positive end of the amplifier TIA is connected to the DC voltage source VDD, the negative end of the amplifier TIA is grounded, and the in-phase input end of the amplifier TIA is connected to the second plate of the coupling capacitor C4. By reducing the capacity of the coupling capacitor C4 (generally tens of pF), the bandwidth of the receiving link can be increased, the falling edge time of the electrical front conductive signal can be reduced, and the purpose of compressing the pulse width can be achieved (such as Figure 3 A in the Figure 3 The effect of B in FIG. 1 is achieved), thereby enhancing the close-range ranging capability of the laser radar 2.

[0068] The conditioning amplifier circuit 30 further includes a sixth resistor R6, a seventh resistor R7, an eighth resistor R8 and a ninth resistor R9. A first end of the sixth resistor R6 is connected to a DC voltage source V DD The first end of the eighth resistor R8 is connected to the inverting input terminal of the amplifier TIA, and the second end of the eighth resistor R8 is grounded; the first end of the ninth resistor R9 is connected to the inverting input terminal of the amplifier TIA, and the second end of the ninth resistor R9 is connected to the output terminal of the amplifier TIA.

[0069] The resistance values ​​of the eighth resistor R8 and the ninth resistor R9 determine the gain of the amplifier TIA. For the power control circuit in which the cathode of the optical receiver 10 is connected to the first voltage source PHV through the first switch switching unit K1, and the anode of the optical receiver 10 is directly connected to the second voltage source NHV, the second end of the sixth resistor R6, the first end of the seventh resistor R7, and the non-inverting input end of the amplifier TIA are all connected to the anode of the optical receiver 10, and the resistance values ​​of the sixth resistor R6 and the seventh resistor R7 determine the potential of the anode of the optical receiver 10.

[0070] The amplitude of the pre-conducting signal changes with the rising speed of the bias voltage Vbias. The greater the preset change rate of the bias voltage Vbias, the greater the amplitude of the pre-conducting signal. The power control circuit 20 controls the bias voltage Vbias of the optical receiver 10 to rise rapidly from the second preset time T2, suppresses the ultra-strong photo-preconducting signal generated by the photo-precursor echo before the first preset time T1, and quickly restores the receiving ability of the optical receiver after the first preset time T1. This control method of the bias voltage Vbias can effectively suppress the generation of the photoelectric conductive signal, but the optical receiver 10 will output a very strong pre-conducting signal, which will also block the detection electrical signal and affect the recognition and detection of the detection electrical signal. The conditioning amplifier circuit 30 can be used to amplify the received electrical signal, and can also perform pulse width shaping processing on the received electrical signal, compress the pulse width of the bias electrical signal, separate the pre-conducting signal and the detection electrical signal from each other, and then distinguish the detection electrical signal in the received electrical signal, and obtain accurate ranging results after sampling.

[0071] like Fig.10 As shown, an embodiment of the present application provides a laser receiving device 1, which also includes a temperature drift compensation circuit 40, which is connected between the optical receiver 10 and the conditioning amplifier circuit 30, and is used to make the change trend of the equivalent resistance of the conditioning amplifier circuit 30 and the temperature drift compensation circuit 40 consistent with the change trend of the resistance of the optical receiver 10.

[0072] The τ value inside the optical receiver 10 has a temperature drift characteristic. Even if the optical receiver 10 receives the same echo light signal, the pulse width of the output received electrical signal will fluctuate with the temperature change. The conditioning amplifier circuit 30 amplifies and pulse-width-shapes the received electrical signal and then outputs it to the back-end sampling module, which will result in different results for the same echo light signal sampling, resulting in poor consistency of the detection results of the laser radar 2, thereby affecting the detection performance of the laser radar 2.

[0073] The internal resistance of the optical receiver 10 decreases with the increase of temperature, and the τ value gradually decreases, and the pulse width of the received electrical signal output by the optical receiver 10 also decreases accordingly. This is an inherent property of the optical receiver 10, which is generally related to its process parameters. A temperature drift compensation circuit 40 is provided between the optical receiver 10 and the conditioning amplifier circuit 30, so that the temperature drift compensation circuit 40 can compensate for the fluctuation of the internal resistance of the optical receiver 10 with the temperature change, thereby ensuring the consistency of the received electrical signal output by the optical receiver 10, so as to improve the detection performance of the laser radar 2.

[0074] like Fig.11 As shown, specifically, the temperature drift compensation circuit 40 includes a third resistor R3 and a first compensation resistor 41; the resistance of the third resistor R3 does not change with temperature; the resistance of the first compensation resistor 41 decreases with the increase of temperature, and the first compensation resistor 41 is connected in parallel with the third resistor R3. Among them, the third resistor R3 adopts a high-precision low-temperature drift resistor, and the resistance of the third resistor R3 hardly changes with temperature fluctuations. The first compensation resistor 41 can be a first thermistor NTC1, which is connected in parallel with the third resistor R3, and the resistance of the first thermistor NTC1 decreases with the increase of temperature. When the operating temperature increases, the internal resistance of the optical receiver 10 decreases with the increase of temperature; at this time, the resistance of the first thermistor NTC1 decreases, the overall resistance of the temperature drift compensation circuit 40 also decreases, and the equivalent total resistance of the temperature drift compensation circuit 40 and the conditioning amplifier circuit 30 also decreases with the increase of temperature, which is consistent with the change trend of the internal resistance of the optical receiver 10, thereby solving the problem of receiving electrical signals fluctuating with temperature. Of course, the first compensation resistor 41 may also be a first thermistor NTC1 and a fourth resistor R4 connected in series, the series branch is connected in parallel with the third resistor R3, the resistance of the first thermistor NTC1 decreases with increasing temperature, and the resistance of the fourth resistor R4 does not change with temperature. The fourth resistor R4 is used to adjust the trend of the total resistance of the first thermistor NTC1 and the fourth resistor R4 connected in series (i.e., the resistance of the first compensation resistor 41) changing with temperature, so that it can be consistent with the change of the internal resistance of the optical receiver 10, and the fourth resistor R4 can be a single resistor or composed of multiple resistors.

[0075] Furthermore, if Fig.12As shown, the temperature drift compensation circuit 40 also includes a second compensation resistor 42, which is also connected in parallel with the third resistor R3, and the resistance of the second compensation resistor 42 decreases as the temperature increases. Among them, the second compensation resistor 42 can be a second thermistor NTC2, which is connected in parallel with the third resistor R3, and the resistance of the second thermistor NTC2 decreases as the temperature increases. When the operating temperature increases, the internal resistance of the optical receiver 10 decreases as the temperature increases; at this time, the resistance of the first thermistor NTC1 and the second thermistor NTC2 both decreases, the overall resistance of the temperature drift compensation circuit 40 also decreases, and the equivalent total resistance of the temperature drift compensation circuit 40 and the conditioning amplifier circuit 30 also decreases as the temperature increases, which is consistent with the change trend of the internal resistance of the optical receiver 10. Compared with only setting the first compensation resistor 41, setting the first compensation resistor 41 and the second compensation resistor 42 at the same time can make the change characteristics of the equivalent total resistance of the temperature drift compensation circuit 40 and the conditioning amplifier circuit 30 with the temperature change more matched with the change characteristics of the internal resistance of the optical receiver 10 with the temperature change, so that the consistency of the received electrical signal output after the echo light signal passes through the optical receiver 10, the temperature drift compensation circuit 40, and the conditioning amplifier circuit 30 is better, and the detection result output by the laser radar 2 is more accurate. Of course, the second compensation resistor 42 can also be a second thermistor NTC2 and a fifth resistor R5 connected in series, and the series branch is connected in parallel with the third resistor R3. The resistance of the second thermistor NTC2 decreases with the increase of temperature, and the resistance of the fifth resistor R5 does not change with temperature. By setting the resistance of the fourth resistor R4 and the fifth resistor R5, when the temperature changes, the change curve of the equivalent total resistance of the temperature drift compensation circuit 40 and the conditioning amplifier circuit 30 can be consistent with the change curve of the internal resistance of the optical receiver 10, thereby ensuring the consistency of the processing of the echo light signal by the laser receiving device 1. It is worth mentioning that the fifth resistor R5 also serves as a compensation resistor, which can adjust and compensate for the signal overshoot after the pulse width of the pre-electrical conductive signal is compressed, so that the pre-electrical conductive signal after the pulse width compression is smoother.

[0076] like Figure 13-Figure 16 As shown, an embodiment of the present application provides a laser receiving device 1, which also includes a filter circuit 50 connected between the optical receiver 10 and the conditioning amplifier circuit 30, and is used to filter out the DC high voltage in the received electrical signal from the optical receiver 10.

[0077] like Fig.13As shown, in one embodiment, the filter circuit 50 includes a filter capacitor C3, which is connected in series with the temperature drift compensation circuit 40 and is arranged between the optical receiver 10 and the conditioning amplifier circuit 30. Specifically, the first plate of the filter capacitor C3 is connected to the optical receiver 10, the second plate of the filter capacitor C3 is connected to the first end of the temperature drift compensation circuit 40, and the second end of the temperature drift compensation circuit 40 is connected to the conditioning amplifier circuit 30. The capacity of the filter capacitor C3 is generally large (such as but not limited to 100nF or 1uF, etc.), so the filter capacitor C3 can filter out the DC high voltage in the received electrical signal from the optical receiver 10 to avoid the DC high voltage from interfering with and affecting the signal, the back-end conditioning amplifier circuit, and even the detection sampling circuit at the back end.

[0078] like Fig.14 As shown, Fig.14 This is a schematic diagram of a specific circuit structure of a laser receiving device in an embodiment of the present application. Fig.14 The connection relationship in the connection will not be described in detail here.

[0079] like Fig.15 As shown, in one embodiment, the filter circuit 50 includes a filter capacitor C3, which is connected in parallel with the temperature drift compensation circuit 40 and is arranged between the optical receiver 10 and the conditioning amplifier circuit 30. Specifically, the first plate of the filter capacitor C3 and the first end of the temperature drift compensation circuit 40 are both connected to the optical receiver 10, and the second plate of the filter capacitor C3 and the second end of the temperature drift compensation circuit 40 are both connected to the conditioning amplifier circuit 30. The filter capacitor C3 can filter out the DC high voltage in the received electrical signal from the optical receiver 10 to prevent the DC high voltage from interfering with and affecting the signal, the back-end conditioning amplifier circuit, and even the detection sampling circuit at the back end.

[0080] like Fig.16 As shown, Fig.16 This is a schematic diagram of a specific circuit structure of a laser receiving device in another embodiment of the present application. Fig.16 The connection relationship in the connection will not be described in detail here.

[0081] Please refer to Fig.17 As shown, the second aspect of the present application proposes a laser radar 2, which includes a laser emitting device 21 and the above-mentioned laser receiving device 1, and the laser emitting device 21 is used to emit a transmission signal. In this design, the laser radar 2 with the above-mentioned laser receiving device 1 can realize close-range detection of the laser radar 2 and can ensure the detection stability and accuracy of the laser radar 2.

[0082] The same or similar numbers in the drawings of this embodiment correspond to the same or similar parts; in the description of this application, it should be understood that if the terms "upper", "lower", "left", "right", etc. indicate an orientation or position relationship based on the orientation or position relationship shown in the drawings, it is only for the convenience of describing this application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, the terms describing the position relationship in the drawings are only used for illustrative purposes and cannot be understood as a limitation on this patent. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0083] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A laser receiving device, characterized in that: include: An optical receiver, used for receiving an echo optical signal and outputting a received electrical signal; a power control circuit connected to the optical receiver, used to control the bias voltage of the optical receiver to increase from a starting bias value to a saturation bias value at a preset change rate, and to control the bias voltage to be less than a breakdown voltage value before a first preset time; wherein the starting bias value is less than the breakdown voltage value, and the saturation bias value is greater than the breakdown voltage value; The conditioning and amplifying circuit is connected to the optical receiver and is used to amplify the received electrical signal output by the optical receiver and adjust the pulse width.

2. The laser receiving device according to claim 1, characterized in that: The power control circuit comprises: a power module connected to the anode of the optical receiver via a switch switching module, and / or connected to the cathode of the optical receiver via the switch switching module; A control module is connected to the switch switching module and is used to control the switch switching module to be in a first switching state before a second preset moment and to be in a second switching state after the second preset moment; wherein the second preset moment is between the start moment and the first preset moment.

3. The laser receiving device according to claim 2, characterized in that: The power supply module includes a first voltage source, the switch switching module includes a first switch switching unit, and the first voltage source is connected to the cathode of the optical receiver through the first switch switching unit; The first connection end of the first switch switching unit is connected to the cathode of the optical receiver, the second connection end of the first switch switching unit is connected to the first voltage source, and the controlled end of the first switch switching unit is connected to the control module; When the first switch switching unit is in the first switching state, the first connection end of the first switch switching unit and the second connection end of the first switch switching unit are not connected; When the first switch switching unit is in the second switching state, the first connection end of the first switch switching unit is connected to the second connection end of the first switch switching unit.

4. The laser receiving device according to claim 3, characterized in that: The power control circuit also includes: a first resistor, wherein a first end of the first resistor is connected to a cathode of the optical receiver, and a second end of the first resistor is connected to a first connection end of the first switch unit; A first capacitor, wherein a first electrode plate of the first capacitor is connected to a first end of the first resistor, and a second electrode plate of the first capacitor is grounded.

5. The laser receiving device according to claim 3, characterized in that: The power control circuit also includes: a second voltage source connected to an anode of the optical receiver; a second resistor, wherein a first end of the second resistor is connected to the anode of the optical receiver, and a second end of the second resistor is connected to the second voltage source; A second capacitor, wherein a first electrode plate of the second capacitor is connected to the second end of the second resistor, and a second electrode plate of the second capacitor is grounded.

6. The laser receiving device according to claim 1, characterized in that: The laser receiving device also includes: The temperature drift compensation circuit is connected between the optical receiver and the conditioning amplifier circuit, and is used to make the variation trend of the equivalent resistance of the conditioning amplifier circuit and the temperature drift compensation circuit consistent with the variation trend of the resistance of the optical receiver.

7. The laser receiving device according to claim 6, characterized in that: The temperature drift compensation circuit comprises a third resistor and a first compensation resistor connected in parallel, the resistance of the third resistor does not change with temperature, and the resistance of the first compensation resistor decreases with increasing temperature.

8. The laser receiving device according to claim 7, characterized in that: The temperature drift compensation circuit further includes a second compensation resistor connected in parallel with the third resistor and the first compensation resistor, and the resistance value of the second compensation resistor decreases as the temperature increases.

9. The laser receiving device according to claim 6, characterized in that: The laser receiving device also includes: The filter circuit is connected between the optical receiver and the conditioning and amplifying circuit, and is used to filter out the DC high voltage in the received electrical signal from the optical receiver.

10. The laser receiving device according to claim 9, characterized in that: The filter circuit includes a filter capacitor, and the filter capacitor is connected in series with the temperature drift compensation circuit, or the filter capacitor is connected in parallel with the temperature drift compensation circuit.

11. The laser receiving device according to claim 1, characterized in that: The conditioning amplifier circuit includes a coupling capacitor and an amplifier, wherein the first plate of the coupling capacitor is connected to the optical receiver for inputting the received electrical signal, the positive end of the amplifier is connected to a DC voltage source, the negative end of the amplifier is grounded, and the in-phase input end of the amplifier is connected to the second plate of the coupling capacitor.

12. The laser receiving device according to claim 11, characterized in that: The conditioning amplifier circuit also includes: a sixth resistor, wherein a first end of the sixth resistor is connected to the DC voltage source, and a second end of the sixth resistor is connected to the non-inverting input end of the amplifier; a seventh resistor, wherein a first end of the seventh resistor is connected to the non-inverting input end of the amplifier, and a second end of the seventh resistor is grounded; an eighth resistor, a first end of the eighth resistor being connected to the inverting input end of the amplifier, and a second end of the eighth resistor being grounded; and A ninth resistor, wherein a first end of the ninth resistor is connected to the inverting input end of the amplifier, and a second end of the ninth resistor is connected to the output end of the amplifier.

13. A laser radar, characterized in that: include: A laser emitting device, used for emitting an emission signal; and A laser receiving device as claimed in any one of claims 1 to 12.

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