CN114690149A

CN114690149A - Laser radar ranging device and method and laser radar

Info

Publication number: CN114690149A
Application number: CN202011602934.4A
Authority: CN
Inventors: 罗高赛; 邓永强; 王泮义
Original assignee: Beijing Wanji Technology Co Ltd
Current assignee: Wuhan Wanji Photoelectric Technology Co Ltd
Priority date: 2020-12-29
Filing date: 2020-12-29
Publication date: 2022-07-01

Abstract

The invention provides a laser radar ranging device and method and a laser radar. The device comprises: a laser emission unit and an APD receiving circuit; the APD receiving circuit includes: the receiving mirror group, the array APD unit, the amplifying circuit unit and the main control unit are connected in sequence; the laser emission unit is connected with the main control unit; the array APD unit comprises a plurality of APD pixels, and each APD pixel has a corresponding receiving field angle; the amplifying circuit unit includes a plurality of first amplifying circuit paths; the APD pixels and the first amplifying circuit paths are the same in number and are correspondingly connected; the plurality of APD pixels are adopted, so that the receiving field angle corresponding to each APD pixel is greatly reduced, and the resolution ratio of the laser radar during distance measurement is improved. The range finding accuracy of the laser radar can be improved. And the signal intensity of the amplified total superposed electric signal formed by the second amplifying circuit path is stronger, so that the ranging capability of the laser radar is improved.

Description

Laser radar ranging device and method and laser radar

Technical Field

The embodiment of the invention relates to the technical field of laser radars, in particular to a distance measuring device and method of a laser radar and the laser radar.

Background

The laser radar has the advantages of high detection precision, high resolution, long detection distance and the like, so that the laser radar has wide application in the fields of map mapping, security protection, scientific research, artificial intelligence, intelligent driving and the like. When the laser radar carries out distance detection by emitting laser and receiving laser echo, a certain included angle is formed between the laser emitted by the laser radar and a target object, and meanwhile, a laser spot which is irradiated on the target object has a divergence angle, so that when the laser is vertically irradiated on the target object, the size of the laser on the target object is the divergence size of the laser spot at the distance; when laser is obliquely incident on a target object at a beta angle, the size of the laser on the target object is formed by two parts, namely the divergence size of a laser spot at the distance and the projection size of the laser spot on the target object at the beta angle.

Therefore, when the laser is obliquely incident on the target object at an angle β, the laser forms a long and narrow projection on the target object. In the prior art, an APD receiving circuit is used to receive a laser echo signal and a corresponding amplifying circuit is used to amplify the laser echo signal, so as to measure the distance of a target object. The APD pixel of the APD unit in the array in the APD receiving circuit has a large field angle, so that the resolution ratio of the laser radar is low, the ranging accuracy of the laser radar is low, and the laser echo signal received by the APD receiving circuit is amplified by the amplifying circuit, so that the signal intensity of the laser echo signal is weak, and the ranging capability of the laser radar is reduced.

Disclosure of Invention

The embodiment of the invention provides a distance measuring device and method of a laser radar and the laser radar, and solves the problems that in the prior art, an APD receiving circuit is adopted to receive a laser echo signal, a corresponding amplifying circuit is adopted to amplify the laser echo signal, and further distance measurement of a target object is carried out. The APD pixel of the APD unit in the array in the APD receiving circuit has a large field angle, so that the resolution ratio of the laser radar is low, the ranging accuracy of the laser radar is low, and the laser echo signal received by the APD receiving circuit is amplified by the amplifying circuit, so that the signal intensity of the laser echo signal is weak, and the technical problem of ranging capability of the laser radar is solved.

In a first aspect, an embodiment of the present invention provides a distance measuring apparatus for a laser radar, including: a laser emission unit and an APD receiving circuit;

the APD receive circuit comprises: the receiving mirror group, the array APD unit, the amplifying circuit unit and the main control unit are connected in sequence; the laser emission unit is connected with the main control unit;

the array APD unit comprises a plurality of APD pixel elements, and each APD pixel element has a corresponding receiving field angle; the amplifying circuit unit comprises a plurality of first amplifying circuit paths;

the APD pixels and the first amplifying circuit paths are the same in number and are correspondingly connected;

each first amplifying circuit path is used for amplifying the corresponding electric signal to form an amplified electric signal;

and the main control unit is used for respectively calculating first distance values between the laser radar and the target object within the corresponding receiving view angle according to the first time difference corresponding to each amplified electric signal, and each first distance value is a distance value between the laser radar and the target object within the corresponding receiving view angle.

Further, in the apparatus as described above, the amplifying circuit unit further includes: a second amplifying circuit path;

each APD pixel is connected with the second amplifying circuit path; the second amplifying circuit path is used for superposing the electric signals corresponding to the APD pixels and amplifying the superposed electric signals to form amplified total superposed electric signals;

the main control unit is further used for calculating a second distance value between the laser radar and the target object in the total receiving field angle according to a second time difference corresponding to the total superposition electric signal; and the second distance value is used for outputting the second distance value as the first distance value of a certain first amplifying circuit path if the first distance value corresponding to the certain first amplifying circuit path is not output.

Further, in the apparatus as described above, the amplifying circuit unit further includes: at least one third amplification circuit path;

the at least two APD pixels are connected with corresponding third amplifying circuit paths;

each third amplifying circuit channel is used for superposing the electric signals of at least two corresponding APD pixels and amplifying the superposed electric signals to form a plurality of amplified superposed electric signals;

the main control unit is further configured to, when a first distance value corresponding to a certain first amplification circuit path is not output, obtain a target third distance value based on an APD pixel connected to the first amplification circuit path, and output the target third distance value as the first distance value of the certain first amplification circuit path; and calculating the distance value between the laser radar and the target object in the corresponding multi-receiving view angle according to a third time difference corresponding to each multi-path superposed electric signal, wherein the third distance value of the target is one of the third distance values, and when the first distance value corresponding to one first amplifying circuit path is not output and the third distance value corresponding to the third amplifying circuit path connected with the APD pixel connected with the first amplifying circuit path is not output, the second distance value is output as the first distance value of one first amplifying circuit path.

Further, in the apparatus as described above, the APD receive circuit further includes: a time discrimination unit;

the time discriminating unit includes: a first time discrimination path, a second time discrimination path and at least one third time discrimination path; the number of the first time discrimination paths is the same as the number of the first amplifying circuit paths.

Further, in the apparatus as described above, each of the first time discrimination paths is configured to discriminate an output time of the corresponding amplified electrical signal;

the second time discrimination path is used for discriminating the output time of the amplified total superimposed electrical signal;

each of the third time discrimination paths is configured to discriminate an output time of the corresponding amplified multiplexed electrical signal.

Further, in the apparatus as described above, the APD receive circuit further includes: a timing unit;

the timing unit includes: a first timing path, a second timing path and at least a third timing path; the number of the first timing paths is the same as the number of the first amplifying circuit paths.

Further, in the apparatus as described above, each of the first timing paths is configured to calculate a first time difference between an output time of the corresponding amplified electrical signal and an emission time of the laser emission signal;

the second timing access is used for calculating a second time difference between the output time of the amplified total superposed electrical signal and the emission time of the laser light-emitting signal;

each of the third timing paths is configured to calculate a third time difference between an output time of the corresponding amplified multi-channel superimposed electrical signal and an emission time of the laser emission signal.

In a second aspect, an embodiment of the present invention provides a ranging method for a laser radar, including:

the laser emission unit emits a laser light-emitting signal under the control of the main control unit;

the receiving mirror group converges the laser diffuse reflection signals reflected by the laser light-emitting signals on the target object to each APD pixel of the APD unit array;

each APD pixel in the APD unit array converts the laser diffuse reflection signal in the corresponding receiving field angle into an electric signal;

each first amplifying circuit passage in the amplifying circuit unit amplifies the corresponding electric signal to form an amplified electric signal;

the main control unit respectively calculates first distance values between the laser radar and the target object in the corresponding receiving field angle according to the first time difference corresponding to each amplified electric signal; and each first distance value is a distance value between the laser radar and the target object within a corresponding receiving view angle.

Further, as described above, in the method, after each APD pixel element in the array APD unit converts the laser diffuse reflection signal in the corresponding receiving view angle into an electrical signal, the method further includes:

a second amplifying circuit passage in the amplifying circuit unit superposes the electric signals corresponding to the APD pixels and amplifies the superposed electric signals to form amplified total superposed electric signals;

the main control unit calculates a second distance value between the laser radar and the target object in the total receiving field angle according to a second time difference corresponding to the total superposition electric signal; and the second distance value is used for outputting the second distance value as the first distance value of a certain first amplifying circuit path if the first distance value corresponding to the certain first amplifying circuit path is not output.

Further, in the method as described above, after each APD pixel element in the array APD unit converts the laser diffuse reflection signal in the corresponding receiving view angle into an electrical signal, the method further includes:

each third amplifying circuit channel in the amplifying circuit unit superposes the electric signals of at least two corresponding APD pixels and amplifies the superposed electric signals to form amplified multi-channel superposed electric signals;

when a first distance value corresponding to a certain first amplifying circuit path is not output, the main control unit acquires a target third distance value based on an APD pixel connected with the first amplifying circuit path, and outputs the target third distance value as the first distance value of the certain first amplifying circuit path; and calculating the distance value between the laser radar and the target object in the corresponding multi-receiving view angle according to a third time difference corresponding to each multi-path superposed electric signal, wherein the third distance value of the target is one of the third distance values, and when the first distance value corresponding to one first amplifying circuit path is not output and the third distance value corresponding to the third amplifying circuit path connected with the APD pixel connected with the first amplifying circuit path is not output, the second distance value is output as the first distance value of one first amplifying circuit path.

Further, the method as described above, further comprising:

each first time discrimination path discriminates the output time of the corresponding amplified electric signal;

the second time discrimination path discriminates the output time of the amplified total superimposed electrical signal;

each of the third time discrimination paths discriminates an output time of the corresponding amplified multiplexed electrical signal.

Further, the method as described above, further comprising:

each first timing path calculates a first time difference between the output time of the corresponding amplified electric signal and the emission time of the laser light-emitting signal;

the second timing path calculates a second time difference between the output time of the amplified total superimposed electrical signal and the emission time of the laser light-emitting signal;

and each third timing path calculates a third time difference between the output time of the corresponding amplified multi-channel superposed electrical signal and the emission time of the laser light-emitting signal.

In a third aspect, an embodiment of the present invention provides a lidar including: the ranging apparatus for a lidar according to any of the first aspects.

The embodiment of the invention provides a laser radar ranging device, a laser radar ranging method and a laser radar, wherein the laser radar ranging device comprises: laser emission unit and APD receiving circuit. Wherein the APD receive circuit comprises: the receiving mirror group, the array APD unit, the amplifying circuit unit and the main control unit are connected in sequence; the laser emission unit is connected with the main control unit; the array APD unit comprises a plurality of APD pixel elements, and each APD pixel element has a corresponding receiving field angle; the amplifying circuit unit comprises a plurality of first amplifying circuit paths; the APD pixels and the first amplifying circuit paths are the same in number and are correspondingly connected; each first amplifying circuit path is used for amplifying the corresponding electric signal to form an amplified electric signal; and the main control unit is used for respectively calculating first distance values between the laser radar and the target object within the corresponding receiving view angle according to the first time difference corresponding to each amplified electric signal, and each first distance value is a distance value between the laser radar and the target object within the corresponding receiving view angle. Therefore, compared with the prior art in which one APD pixel is adopted, the receiving field angle corresponding to each APD pixel is far reduced by adopting a plurality of APD pixels, each APD pixel can convert laser diffuse reflection signals in the corresponding receiving field angle into electric signals, and after the electric signals are amplified through the corresponding first amplifying circuit, the main control unit calculates the distance value between the laser radar and the target object in the corresponding receiving field angle, so that each receiving field angle can calculate the corresponding distance value, and the resolution of the laser radar during distance measurement is improved. The range finding accuracy of the laser radar can be improved.

It should be understood that what is described in the summary above is not intended to limit key or critical features of embodiments of the invention, nor is it intended to limit the scope of the invention. Other features of the present invention will become apparent from the following description.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 is an application scene diagram of a laser light emitting signal emitted by a ranging method of a laser radar according to an embodiment of the present invention;

fig. 2 is an application scene diagram of a laser radar ranging method receiving a laser diffuse reflection signal according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of a ranging apparatus of a laser radar according to an embodiment of the present invention;

fig. 4 is a schematic structural diagram of a distance measuring apparatus of a laser radar according to a second embodiment of the present invention;

fig. 5 is a flowchart of a ranging method of a laser radar according to a third embodiment of the present invention;

fig. 6 is a flowchart of a ranging method of a laser radar according to a fourth embodiment of the present invention;

fig. 7 is a flowchart of a ranging method of a laser radar according to a fifth embodiment of the present invention;

fig. 8 is a flowchart of a ranging method of a laser radar according to a sixth embodiment of the present invention;

fig. 9 is a flowchart of a ranging method of a laser radar according to a seventh embodiment of the present invention.

Reference numerals:

1-laser radar 11-laser emission unit 2-target object 21-light spot 22-projection 12-receiving mirror group 13-array APD unit 131-laser diffuse reflection signal 132-receiving visual angle 133-APD pixel 14-amplifying circuit unit 141-first amplifying circuit path 142-second amplifying circuit path 143-third amplifying circuit path 15-time discrimination unit 151-first time discrimination path 152-second time discrimination path 153-third time discrimination path 16-timing unit 161-first timing path 162-second timing path 163-third timing path 17-main control unit

Detailed Description

Embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. While certain embodiments of the present invention are shown in the drawings, it should be understood that the present invention may be embodied in various forms and should not be construed as limited to the embodiments set forth herein, but rather are provided for a more thorough and complete understanding of the present invention. It should be understood that the drawings and the embodiments of the present invention are illustrative only and are not intended to limit the scope of the present invention.

The terms "first," "second," "third," "fourth," and the like in the description and in the claims, and in the above-described drawings, if any, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used are interchangeable under appropriate circumstances such that the embodiments of the invention described herein are, for example, capable of operation in sequences other than those illustrated or otherwise described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

First, an application scenario of the ranging method of the laser radar provided by the embodiment of the present invention is described. As shown in fig. 1 and fig. 2, in an application scenario corresponding to the ranging method of the laser radar according to the embodiment of the present invention, a ranging device of the laser radar is mounted in the laser radar 1, and the laser radar may be mounted on a moving object or on a road side. The moving object may be an autonomous vehicle, an intelligent robot, or the like.

As shown in fig. 1, 2 and 3, the ranging apparatus for a lidar includes: a laser emitting unit 11 and an APD receiving circuit; the APD receiving circuit includes: the receiving mirror group 12, the array APD unit 13, the amplifying circuit unit 14 and the main control unit 17 are connected in sequence; the laser emitting unit 11 is connected with the main control unit 17; the array APD unit 13 includes a plurality of APD pixels 133, each APD pixel 133 having a corresponding receive field of view 132; the amplifying circuit unit 14 includes a plurality of first amplifying circuit paths 141; the APD pixels 133 and the first amplifying circuit paths 141 are the same in number and are sequentially connected correspondingly. The laser emitting unit 11 emits a laser light emitting signal under the control of the main control unit 17 after the laser radar turns on the ranging device of the laser radar.

For example, as shown in fig. 1, a laser emission signal of the lidar is incident obliquely at an angle β onto the target object 2, and the laser forms an elongated projection 22 on the target object 2. The size of the laser on the target object 2 is formed by two parts, namely the divergence size of the laser spot 21 at the distance and the projection 22 size of the laser spot 21 on the target object 2 at the angle beta.

As shown in fig. 2 and fig. 3, the laser spot 21 and the projection 22 are subjected to diffuse reflection to form a laser diffuse reflection signal 131, the laser diffuse reflection signal 131 is received by the receiving mirror group 12, and the receiving mirror group 12 converges the laser diffuse reflection signal 131 on each APD pixel 133 of the array APD unit 13. The APD pixels 133 may be arranged in a row at equal intervals, and for the target object 2, each APD pixel 133 has a corresponding receiving angle of view 132, and the receiving angle of view 132 corresponding to each APD pixel 133 may be θ 1 to θ N, respectively. Each APD pixel 133 in the array APD unit 13 converts the laser diffuse reflection signal 131 in the corresponding receiving field angle 132 into an electrical signal; each first amplifier circuit path 141 in the amplifier circuit unit 14 amplifies the corresponding electrical signal to form an amplified electrical signal; the main control unit 17 calculates a first distance value between the laser radar and the target object 2 within the corresponding receiving field angle 132 according to the first time difference corresponding to each amplified electrical signal. Because the array APD unit 13 includes a plurality of APD pixels 133, each APD pixel 133 can convert the laser diffuse reflection signal 131 in the corresponding receiving view angle 132 into an electrical signal, and after the electrical signal is processed by the corresponding first amplifying circuit path 141 and the main control unit 17, calculate the distance value in the corresponding receiving view angle 132. Compared with the prior art that one APD pixel 133 is adopted, the receiving field angle 132 corresponding to each APD pixel 133 is greatly reduced by adopting a plurality of APD pixels 133, each APD pixel can convert laser diffuse reflection signals in the corresponding receiving field angle into electric signals, and after the electric signals are amplified by the corresponding first amplifying circuit, the main control unit calculates the distance value between the laser radar and the target object in the corresponding receiving field angle, so that the corresponding distance value can be calculated by each receiving field angle, and the resolution of the laser radar during distance measurement is improved. The range finding accuracy of the laser radar can be improved.

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

Example one

Fig. 3 is a schematic structural diagram of a ranging apparatus of a laser radar according to an embodiment of the present invention, and as shown in fig. 3, the ranging apparatus of the laser radar according to the embodiment includes: laser emitting unit 11 and APD receiving circuit.

Wherein the APD receive circuit comprises: a receiving mirror group 12, an array APD unit 13, an amplifying circuit unit 14 and a main control unit 17 which are connected in sequence. The array APD cell 13 includes a plurality of APD picture elements 133, each APD picture element 133 having a corresponding receive field angle 132; the amplifying circuit unit 14 includes a plurality of first amplifying circuit paths 141;

the APD pixels 133 and the first amplifying circuit paths 141 are the same in number and are correspondingly connected.

In this embodiment, the laser emitting unit is connected to the main control unit. And the laser emitting unit is used for emitting laser light emitting signals under the control of the main control unit. Specifically, after the ranging device of the laser radar is started, the main control unit sends a control instruction to the laser emission unit, the laser emission unit is controlled to emit a laser light emission signal through the control instruction, and the radiation divergence angle of the laser light emission signal can be alpha. The laser emission signal may strike the target object at an angle β. If β is equal to 90 degrees, the laser emission signal is directed vertically onto the target object. The size of the laser on the target object is the divergence size of the laser spot at that distance. If the beta is not equal to 90 degrees, the laser light-emitting signal is obliquely incident to the target object. The laser forms an elongated projection on the target object. The size of the laser on the target object is formed by two parts, namely the divergence size of the laser spot at the distance and the projection size of the laser spot on the target object at the angle beta. In this embodiment, the value of the angle β at which the laser light emitting signal emitted by the laser emitting unit hits the target object is not limited.

In this embodiment, as shown in fig. 2, after the laser light emission signal hits the target object, diffuse reflection occurs. Forming a laser diffuse reflection signal. The distance measuring device of the laser radar comprises a receiving mirror group 12, wherein the receiving mirror group 12 is used for converging a laser diffuse reflection signal 131, which is reflected by a laser light emitting signal on a target object 2, to each APD pixel 133 of an array APD unit 13. Specifically, the receiving lens group 12 includes a plurality of receiving lenses, receives the laser diffuse reflection signals 131 of different areas of the target object 2, and converges the laser diffuse reflection signals 131 through the plurality of receiving lenses. In this embodiment, the number and arrangement of the receiving lenses in the receiving lens group 12 are not limited in this embodiment.

In this embodiment, as shown in fig. 3, the array APD unit 13 is an array avalanche light emitting diode unit. A plurality of APD picture elements 133 are included in the array APD cell 13, each APD picture element 133 having a corresponding receive field angle 132. Each APD pixel element 133 is configured to convert the laser diffuse reflection signal 131 within the corresponding receiving field angle 132 into an electrical signal.

As an alternative, the APD pixels 133 can be arranged in a row at equal intervals and located at the rear side of the optical path of the receiving mirror group 12. Then, after the receiving mirror group 12 converges the laser diffuse reflection signal 131, the laser diffuse reflection signal 131 correspondingly receiving the field angle 132 in the APD pixel 133 is received by the corresponding APD pixel 133. Each APD pixel 133 performs photoelectric conversion on the laser diffuse reflection signal 131 within the corresponding receiving angle of view, and outputs a corresponding electrical signal. If the number of the APD pixels 133 is N, the laser diffuse reflection signal 131 is divided into N parts, where the ith (i is greater than or equal to 1 and less than or equal to N) part of the laser diffuse reflection signal 131 is received by the ith (i is greater than or equal to 1 and less than or equal to N) APD pixel 133 with the receiving field angle 132 of θ i (i is greater than or equal to 1 and less than or equal to N), and the ith APD pixel 133 converts the laser diffuse reflection signal 131 with the receiving field angle 132 of θ i into a corresponding electrical signal and outputs the corresponding electrical signal through the corresponding output node P1 i. Wherein, the output nodes corresponding to the N APD pixels 133 are P respectively₁₁～P_1N. Wherein N is more than or equal to 2.

It can be understood that if the laser emission signal is vertically incident on the target object 2, the corresponding receiving field angles 132 of the APD pixels 133 are equal. If the laser light emitting signal is obliquely incident on the target object 2, the corresponding receiving field angles 132 of the APD pixels 133 are not equal.

In this embodiment, after the APD pixel 133 converts the laser diffuse reflection signal 131 corresponding to the receiving field angle 132 into a corresponding electrical signal, the electrical signal is very weak, so that each electrical signal needs to be amplified for accurate ranging. So that at the back end of each APD pixel element 133 it passes through output node P₁₁～_P1NThe first amplifier circuit paths 141 are connected in one-to-one correspondence. If the number of the APD pixels 133 is NThe number of first amplifier circuit paths 141 is also N. Each first amplifier circuit path 141 amplifies a corresponding electrical signal to form an amplified electrical signal. The output nodes of the first amplifying circuit path 141 may be P₂₁～P_2N. N is more than or equal to 2. The amplified electric signal is outputted from the output node of each first amplifier circuit path 141.

In this embodiment, the main control unit 17 passes through the output node P of the first amplifying circuit path 141₂₁～P_2NEach of the amplifier circuit paths 141 is connected to receive the amplified electrical signal transmitted from each of the amplifier circuit paths 141. The main control unit 17 is configured to determine a first time difference between an output time corresponding to each amplified electrical signal and an emission time of the laser emission signal, and calculate a first distance value between the laser radar and the target object 2 within the corresponding receiving view angle 132 according to each first time difference. Each first distance value is a distance value between the laser radar and the target object 2 within the corresponding reception angle of view. In particular, both the time of flight and the time of transmission of the corresponding laser signal are included in the first time difference. Therefore, the transmission time of each electrical signal can be determined first, then the difference between the first time difference and the corresponding transmission time of the electrical signal is calculated, that is, the flight time of the corresponding laser signal can be determined, and the distance value between the laser radar and the target object 2 within the corresponding receiving field angle 132 is calculated according to the flight time of the laser signal, and the distance value is the first distance value.

The transmission time of each path of electric signal can be predetermined and stored, and the main control unit 17 can directly obtain the transmission time of each path of electric signal.

In this embodiment, if the first distance values corresponding to each first amplification path are normally output, these first distance values are the distance values between the laser radar and the target object within the corresponding receiving field angle.

It should be noted that the laser radar in this embodiment may be a mechanical laser radar, and may also be another type of laser radar, which is not limited in this embodiment.

The range unit of lidar that this embodiment provided includes: a laser emission unit and an APD receiving circuit; the APD receiving circuit includes: the receiving mirror group, the array APD unit, the amplifying circuit unit and the main control unit are connected in sequence; the laser emission unit is connected with the main control unit; the array APD unit comprises a plurality of APD pixels, and each APD pixel has a corresponding receiving field angle; the amplifying circuit unit includes a plurality of first amplifying circuit paths; the APD pixels and the first amplifying circuit paths are the same in number and are correspondingly connected; each first amplifying circuit path is used for amplifying the corresponding electric signal to form an amplified electric signal; and the main control unit is used for respectively calculating first distance values between the laser radar and the target object within the corresponding receiving view angles according to the first time differences corresponding to the amplified electric signals, and each first distance value is a distance value between the laser radar and the target object within the corresponding receiving view angle. Therefore, compared with the prior art in which one APD pixel is adopted, the receiving field angle corresponding to each APD pixel is far reduced by adopting a plurality of APD pixels, each APD pixel can convert laser diffuse reflection signals in the corresponding receiving field angle into electric signals, and after the electric signals are amplified through the corresponding first amplifying circuit, the main control unit calculates the distance value between the laser radar and the target object in the corresponding receiving field angle, so that each receiving field angle can calculate the corresponding distance value, and the resolution of the laser radar during distance measurement is improved. The range finding accuracy of the laser radar can be improved.

Example two

Fig. 4 is a schematic structural diagram of a distance measuring device of a laser radar according to a second embodiment of the present invention, and as shown in fig. 4, the distance measuring device of a laser radar according to the present embodiment further refines the APD receiving circuit 13 and the amplifying circuit unit 14 on the basis of the distance measuring device of a laser radar according to the embodiment shown in fig. 3, and further includes a time discriminating unit 15 and a timing unit 16. The ranging apparatus for lidar according to this embodiment further includes the following solutions.

In this embodiment, the amplifying circuit unit 14 further comprises a second amplifying circuit path 142. Each APD pixel element 133 is in via connection with a second amplification circuit 142.

Specifically, in the present embodiment, the second amplification circuit path 142 is distinguished from the first amplification circuit path 141. There is one second amplification circuit path 142. Each APD pixel element 133 is connected to a second amplification circuit path 142.

The second amplifying circuit path 142 is configured to superimpose the electrical signals corresponding to the APD pixels 133, and amplify the superimposed electrical signals to form an amplified total superimposed electrical signal.

Specifically, if there are N APD pixels 133, each APD pixel 133 passes through the output node P₁₁～P_1NIs connected to second amplification circuit path 142. After the APD pixels 133 convert the corresponding laser diffuse reflection signals 131 into electrical signals, each electrical signal almost simultaneously reaches the corresponding second amplifying circuit path 142. The second amplifying circuit path 142 can superpose N electrical signals, and the signal strength of the superposed electrical signals is much larger than that of each electrical signal. And after the superposed electric signals are amplified, the signal intensity of the formed amplified total superposed electric signals is stronger than the signal intensities of other N amplified electric signals.

In this embodiment, the main control unit 17 is not only connected to each first amplifying circuit path 141, but also connected via an output node P_2(N+1)Is connected to second amplification circuit path 142. The main control unit 17 is further configured to calculate a second distance value between the laser radar and the target object within the total receiving field angle according to a second time difference corresponding to the total superimposed electrical signal.

In particular, both the time of flight of the corresponding laser signal and the time of transmission of the corresponding electrical signal are included in the second time difference. Therefore, the transmission time of the corresponding electric signal can be determined, then the difference value between the second time difference and the transmission time of the corresponding electric signal is calculated, that is, the flight time of the corresponding laser signal can be determined, and the distance value between the laser radar and the target object within the total receiving field angle is calculated according to the flight time of the laser signal, wherein the distance value is the second distance value.

And the second distance value is used for outputting the second distance value as the first distance value of a certain first amplifying circuit path if the first distance value corresponding to the certain first amplifying circuit path is not output.

In this embodiment, because the plurality of APD pixels are all connected to the second amplifying circuit path, the signal intensity of the amplified total superimposed electrical signal formed by the second amplifying circuit path is stronger than the signal intensity of the electrical signal amplified by each first amplifying circuit path, and the electrical signal amplified by each first amplifying circuit path is still weak, so that the distance can be effectively measured through the second amplifying circuit path and the main control unit when the distance cannot be effectively measured, thereby improving the distance measuring capability of the laser radar. And when the first distance value corresponding to a certain first amplifying circuit path is not output, the second distance value is output as the first distance value of a certain first amplifying circuit path, and when a certain first amplifying circuit path is damaged, the resolution ratio of the laser radar during distance measurement and the ranging accuracy of the laser radar are still ensured.

Optionally, in this embodiment, the amplifying circuit unit 14 further includes: at least one third amplification circuit path 143;

at least two APD picture elements 133 are connected to corresponding third amplification circuit paths 143.

Each third amplifying circuit path 143 is configured to superimpose the electrical signals of the corresponding at least two APD pixels 133, and amplify the superimposed electrical signals to form multiple amplified superimposed electrical signals.

The main control unit 17 is further configured to, when a first distance value corresponding to a certain first amplification circuit path is not output, obtain a third target distance value based on an APD pixel element connected to the first amplification circuit path, and output the third target distance value as the first distance value of the certain first amplification circuit path; and when the first distance value corresponding to a certain first amplifying circuit path is not output and the third distance value corresponding to a third amplifying circuit path connected with an APD pixel of the first amplifying circuit path is not output, outputting the second distance value as the first distance value of the certain first amplifying circuit path.

In the present embodiment, the third amplification circuit path 143 is different from the first amplification circuit path 141 and the second amplification circuit path 142.

As an optional implementation manner, in this embodiment, at least two adjacent APD image elements 133 are connected to the corresponding third amplification circuit paths 143, and at least two APD image elements 133 connected to each third amplification circuit path 143 are different. For example, the number of the third amplifier circuit paths 143 is 3. The first third amplifier circuit path is connected to the first APD pixel element and the second APD pixel element. The second third amplifying circuit path is connected with the third APD pixel element and the fourth APD pixel element. And the third amplifying circuit path is connected with the fifth APD pixel and the sixth APD pixel. Each third amplifying circuit path is used for superposing the electric signals of at least two corresponding adjacent APD pixels and amplifying the superposed electric signals to form a plurality of amplified superposed electric signals. The main control unit calculates a third distance value between the laser radar and the target object in the corresponding multi-receiving view angle according to a third time difference corresponding to each multi-path superposed electric signal,

in this alternative embodiment, the range-finding capability of the lidar may be improved, although the resolution of the lidar is reduced appropriately. There is more selectivity to the resolution of the lidar. And when a certain first amplifying circuit path is damaged, the resolution ratio of the laser radar during distance measurement and the ranging accuracy of the laser radar are still ensured.

As another optional implementation, in this embodiment, the distance measurement may be selectively performed on an important region formed by a plurality of receiving view angles according to the receiving view angle corresponding to the laser radar APD pixel 133. For example, at least two APD picture elements 133 in the middle can be connected to corresponding third amplification circuit paths 143. Each third amplifying circuit path 143 is configured to superimpose the electrical signals of the corresponding at least two APD pixels 133, and amplify the superimposed electrical signals to form multiple amplified superimposed electrical signals. And the main control unit calculates a third distance value between the laser radar and the target object in the corresponding multi-receiving view angle according to a third time difference corresponding to each multi-path superposed electric signal. In this alternative embodiment, the range measurement can be performed in a targeted manner for an area of interest that is formed by a plurality of reception angles of view.

It should be noted that in the above two alternative embodiments, the output node of each third amplifying circuit path 143 can be represented as P_2h. Wherein h is more than or equal to (N +1) and is less than or equal to M. M is the sum of the number of first amplifier circuit paths 141, second amplifier circuit paths 142, and third amplifier circuit paths 143.

Optionally, in this embodiment, the APD receiving circuit 13 further includes: a time discriminating unit 15.

The time discriminating unit 15 includes: a first time discriminating passage 151, a second time discriminating passage 152 and at least one third time discriminating passage 153; the number of first timing discrimination paths 151 is the same as the number of first amplifier circuit paths 141.

In the present embodiment, each first timing discrimination path 151 is used to discriminate the output timing of the corresponding amplified electrical signal. And a second timing discrimination path 152 for discriminating an output timing of the amplified total superimposed electric signal. Each third time discriminating path 153 discriminates the output time of the corresponding amplified multiplexed electric signal.

Specifically, in the present embodiment, the back end of each first amplification circuit path 141 passes through the output node P₂₁～P_2NThe first time discrimination paths 151 are connected in one-to-one correspondence, and each of the first time discrimination paths 151 is used to discriminate an output time of the corresponding amplified electrical signal. That is, each first timing discrimination path 151 discriminates the timing at which the corresponding amplified electric signal is output from the corresponding first amplification circuit path 141. Specifically, the time when the amplified electrical signal is output from the corresponding first amplification circuit path 141 can be identified by detecting the time when the leading edge of the amplified electrical signal comes. If the number of the first amplifying circuit paths 141 is N, the number of the first time discriminating paths 151 is N, and the output nodes of the first time discriminating paths 151 may be P₃₁～P_3N。N≥2。

Specifically, in the present embodiment, the second time discrimination path 152 is distinguished from the first time discrimination path 151. The second moment discriminates between the paths 152 as one. Second amplification circuit path 142 passes through output node P_2(N+1)Connected to the second time discrimination path 152. And a second timing discrimination path 152 for discriminating an output timing of the amplified total superimposed electric signal. That is, the second timing discrimination path 152 discriminates the timing at which the amplified total superimposed electric signal is output from the second amplification circuit path 142. Specifically, the time when the amplified total superimposed electrical signal is output from the second amplification circuit path 142 can be identified by detecting the time when the leading edge of the amplified total superimposed electrical signal comes. Wherein, the output node of the second time discriminating path 152 may be P_3(N+1)。

Specifically, in the present embodiment, the third timing discrimination path 153 is distinguished from the first timing discrimination path 151 and the second timing discrimination path 152. The third time discrimination passage 153 is at least one. Third amplification circuit path 143 passes through output node P_2hAnd is connected to the third time discrimination path 153. And a third time discriminating path 153 for discriminating the output time of the corresponding amplified multiple superimposed electrical signals. That is, the second timing discrimination path 152 discriminates the timing at which the amplified multiple superimposed electric signals are output from the third amplification circuit path 143. Specifically, the time when the amplified multi-channel superimposed electrical signal is output from the third amplification circuit path 143 can be identified by detecting the time when the leading edge of the amplified multi-channel superimposed electrical signal comes. Wherein, the output node of the third time discriminating path 153 may be P_3h。

Optionally, in this embodiment, the APD receiving circuit further includes: a timing unit 16;

the time counting unit 16 includes: a first timing path 161, a second timing path 162 and at least a third timing path 163; the number of first timing paths 161 is the same as the number of first amplifier circuit paths 141.

Each first timing path 161 is configured to calculate a first time difference between an output time of the corresponding amplified electrical signal and an emission time of the laser emission signal. And a second timing path 162 for calculating a second time difference between the output time of the amplified total superimposed electrical signal and the emission time of the laser emission signal. Each third timing path 163 is configured to calculate a third time difference between the output time of the corresponding amplified multi-channel superimposed electrical signal and the emission time of the laser emission signal.

Specifically, in the present embodiment, when the distance between the laser radar and the target object is calculated, the time of flight of the laser signal needs to be measured, so that the distance is calculated according to the time of flight of the laser signal. The back end of the discrimination path 151 passes through the output node P at each first timing₃₁～P_3NThe first timing path 161 is connected in a one-to-one correspondence. The first timing path 161 is used for calculating a first time difference between the output time of the corresponding amplified electrical signal and the emission time of the laser emission signal. The first time difference is a time difference between an output time of the corresponding amplified electrical signal and an emission time of the laser emission signal. If the number of the first timing path 151 is N, the number of the first timing path 161 is N, and the output nodes of the first timing path 161 may be P₄₁～P_4N。N≥2。

It will be appreciated that the first time difference calculated in the first timing path 161 includes both the corresponding electrical signal transmission time and the corresponding laser signal time of flight. The flight time of the laser signal is the sum of the flight time of the laser emitting signal and the flight time of the laser diffuse reflection signal 131.

In this embodiment, the main control unit 17 passes through the output node P of the first timing path 161₄₁～P_4NEach of the first timing paths 161 is connected to receive each of the first time differences transmitted by each of the first timing paths 161. And the main control unit 17 is configured to calculate first distance values between the laser radar and the target object within corresponding receiving field angles according to the first time differences. In particular, both the time of flight and the time of transmission of the corresponding laser signal are included in the first time difference. So that the transmission time of each electrical signal can be determined first, and then the first time difference and the corresponding transmission time of the electrical signal will be calculatedAnd determining the flight time of the corresponding laser signal according to the difference value, and calculating the distance value between the laser radar and the target object in the corresponding receiving view angle according to the flight time of the laser signal, wherein the distance value is a first distance value.

Specifically, in the present embodiment, the second timing path 162 is distinguished from the first timing path 161. The second timing path 162 is one. The second time discrimination path 152 passes through the output node P_3(N+1)Connected to the second timing path 162. And a second timing path 162 for calculating a second time difference between the output time of the amplified total superimposed electrical signal and the emission time of the laser emission signal. The second time difference is a time difference between an output time of the amplified total superimposed electrical signal and an emission time of the laser emission signal. The output nodes of the second timing path 162 may be P_4(N+1)。

Similarly, the second time difference calculated by the second timing path 162 includes both the electrical signal transmission time and the time of flight of the corresponding laser signal.

In this embodiment, the main control unit 17 is not only connected to each first timing path 161, but also connected to each first timing path via an output node P_4(N+1)Connected to the second timing path 162. The main control unit 17 is further configured to calculate a second distance value between the laser radar and the target object within the total receiving field angle according to the second time difference. In particular, both the time of flight of the corresponding laser signal and the time of transmission of the corresponding electrical signal are included in the second time difference. Therefore, the transmission time of the corresponding electric signal can be determined, then the difference value between the second time difference and the transmission time of the corresponding electric signal is calculated, that is, the flight time of the corresponding laser signal can be determined, and the distance value between the laser radar and the target object within the total receiving field angle is calculated according to the flight time of the laser signal, wherein the distance value is the second distance value.

In this embodiment, the third timing path 163 is different from the first timing path 161 and the second timing path 162. The third timing path 163 is at least one. The third time discriminating path 153 is connected to the corresponding third timing path 163 via the output node P3 h. Each third timing path 163 for calculating a corresponding amplified multiple pathA third time difference between the output timing of the superimposed electrical signal and the emission timing of the laser emission signal. The third time difference is the time difference between the output time of the amplified multi-channel superposed electric signals and the emission time of the laser light-emitting signals. The output nodes of the third timing path 163 may be P_4h。

In this embodiment, the main control unit 17 is not only connected to the first timing path 161 and the second timing path 162, but also connected to the output node P_4hAnd is connected to each third timing path 163. And the main control unit 17 is configured to calculate a third distance value between the laser radar and the target object within the corresponding multi-receiving view angle according to each third time difference. In particular, both the time of flight of the corresponding laser signal and the time of transmission of the corresponding electrical signal are included in the third time difference. Therefore, the transmission time of the corresponding electric signal can be determined, then the difference value between the third time difference and the transmission time of the corresponding electric signal is calculated, that is, the flight time of the corresponding laser signal can be determined, and the distance value between the laser radar and the target object in the corresponding multiple receiving view angles is calculated according to the flight time of the laser signal, wherein the distance value is the third distance value.

In the distance measuring apparatus for laser radar provided in this embodiment, the amplifying circuit unit 14 further includes at least one third amplifying circuit path 143, the time discriminating unit 15 further includes at least one third time discriminating path 153, and the timing unit 16 further includes at least one third timing path 163; at least two APD pixels 133 are connected to corresponding third amplification circuit paths 143; the third amplifying circuit paths 143, the third time discriminating path 153, and the third timing path 163 are the same in number and are connected in order. Each third amplifying circuit path 143 is configured to superimpose electrical signals of at least two corresponding APD pixels 133, and amplify the superimposed electrical signals to form amplified multiple superimposed electrical signals; each third time discrimination path 153 for discriminating an output time of the corresponding amplified multi-path superimposed electrical signal; each third timing path 163 is configured to calculate a third time difference between the output time of the corresponding amplified multi-channel superimposed electrical signal and the emission time of the laser emission signal; and the main control unit 17 is configured to calculate a third distance value between the laser radar and the target object within the corresponding multi-receiving view angle according to each third time difference. Since the third amplifying circuit path 143 can selectively superimpose and amplify a plurality of electric signals, a distance measurement can be selectively performed on a plurality of areas where the receiving angles of view are located by the third amplifying circuit path 143, the third time discriminating path 153, the third timing path 163, and the main control unit 17. The range measurement can be performed on the focal region composed of a plurality of reception field angles in a targeted manner. If at least two adjacent APD pixel elements 133 are connected to the corresponding third amplification circuit path 143, and at least two APD pixel elements 133 connected to each third amplification circuit path 143 are different. The resolution of the lidar may also be varied, with greater selectivity to the resolution of the lidar.

EXAMPLE III

Fig. 5 is a flowchart of a ranging method of a lidar according to a third embodiment of the present invention, and as shown in fig. 5, the ranging method of a lidar according to the third embodiment of the present invention may employ the ranging apparatus of a lidar according to the embodiment shown in fig. 3, and then the ranging method of a lidar according to the present embodiment includes the following steps:

step 501, the laser emission unit emits a laser light emission signal under the control of the main control unit.

Specifically, in this embodiment, after the ranging apparatus of the laser radar is started, the main control unit sends a control instruction to the laser emitting unit, and the laser emitting unit is controlled to emit a laser emitting signal through the control instruction, and the laser emitting signal can be emitted onto the target object at an angle β. In this embodiment, the value of the angle β at which the laser light emitting signal emitted by the laser emitting unit hits the target object is not limited.

Step 502, a receiving mirror group converges laser diffuse reflection signals reflected by laser light-emitting signals on a target object to each APD pixel of an APD array unit.

In this embodiment, the receiving lens group includes a plurality of receiving lenses, receives laser diffuse reflection signals of different areas of the target object, and converges the laser diffuse reflection signals through the plurality of receiving lenses. And converging the laser diffuse reflection signals to each APD pixel of the APD unit array.

Step 503, each APD pixel in the array APD unit converts the laser diffuse reflection signal in the corresponding receiving field angle into an electrical signal.

In this embodiment, if the number of the APD pixels is N, the laser diffuse reflection signal is divided into N parts, where the ith (i is not less than 1 and not more than N) part of the laser diffuse reflection signal is received by the ith (i is not less than 1 and not more than N) APD pixel receiving the field angle θ i (i is not less than 1 and not more than N), and the ith APD pixel converts the laser diffuse reflection signal receiving the field angle θ i into a corresponding electrical signal and then passes through the corresponding output node P_1iAnd (6) outputting.

In step 504, each first amplifying circuit path in the amplifying circuit unit amplifies the corresponding electrical signal to form an amplified electrical signal.

Step 505, the main control unit respectively calculates a first distance value between the laser radar and the target object within a corresponding receiving field angle according to the first time difference corresponding to each amplified electric signal; each first distance value is a distance value between the laser radar and the target object within the corresponding receiving view angle.

The APD pixels and the first amplifying circuit are the same in number and are correspondingly connected.

The ranging method of the laser radar provided in this embodiment is performed by the apparatus shown in fig. 3, and the implementation principle and the technical effect are similar, which are not described herein again.

Example four

Fig. 6 is a flowchart of a ranging method of a lidar according to a fourth embodiment of the present invention, and as shown in fig. 6, a ranging method of a lidar according to the fourth embodiment of the present invention may employ the ranging apparatus of a lidar according to the embodiment shown in fig. 4, where step 601 of the ranging method of a lidar according to the present embodiment is executed at the same time as step 504 of the ranging method of a lidar according to fig. 5, and the ranging method of a lidar according to the present embodiment further includes the following steps after step 503:

step 601, superposing the electric signals corresponding to the APD pixels by a second amplifying circuit in the amplifying circuit unit, and amplifying the superposed electric signals to form an amplified total superposed electric signal.

Step 602, the main control unit calculates a second distance value between the laser radar and the target object within the total receiving field angle according to a second time difference corresponding to the total superimposed electrical signal; the second distance value is used for outputting the second distance value as the first distance value of a certain first amplifying circuit path if the first distance value corresponding to the certain first amplifying circuit path is not output.

EXAMPLE five

Fig. 7 is a flowchart of a ranging method of a lidar according to a fifth embodiment of the present invention, and as shown in fig. 7, a ranging method of a lidar according to the fifth embodiment of the present invention may employ the ranging apparatus of a lidar according to the embodiment shown in fig. 4, where step 701 of the ranging method of a lidar according to the present embodiment is executed at the same time as step 504 of the ranging method of a lidar according to fig. 5, and the ranging method of a lidar according to the present embodiment further includes the following steps after step 503:

and 701, superposing the electric signals of the at least two corresponding APD pixels by each third amplifying circuit channel, and amplifying the superposed electric signals to form a plurality of amplified superposed electric signals.

Step 702, when a first distance value corresponding to a certain first amplification circuit path is not output, the main control unit acquires a target third distance value based on an APD pixel connected to the first amplification circuit path, and outputs the target third distance value as the first distance value of the certain first amplification circuit path; and when the first distance value corresponding to a certain first amplifying circuit path is not output and the third distance value corresponding to a third amplifying circuit path connected with an APD pixel of the first amplifying circuit path is not output, outputting the second distance value as the first distance value of the certain first amplifying circuit path.

EXAMPLE six

Fig. 8 is a flowchart of a ranging method of a lidar according to a sixth embodiment of the present invention, and as shown in fig. 8, the ranging method of the lidar according to the embodiment of the present invention may adopt the ranging apparatus of the lidar according to the embodiment of fig. 4, where the ranging method of the lidar according to the present embodiment further includes the following steps after step 504 of the ranging method of the lidar shown in fig. 5, and after step 601 of the ranging method of the lidar shown in fig. 6 or step 701 of the ranging method of the lidar shown in fig. 7:

step 801, each first time identification path identifies the output time of the corresponding amplified electric signal; the second time identification path identifies the output time of the amplified total superposed electric signal; each third time discrimination path discriminates the output time of the corresponding amplified multiplexed electrical signal.

Step 802, each first timing path calculates a first time difference between the output time of the corresponding amplified electrical signal and the emission time of the laser light-emitting signal; the second timing path calculates a second time difference between the output time of the amplified total superposed electrical signal and the emission time of the laser light-emitting signal; each third timing path calculates a third time difference between the output time of the corresponding amplified multi-channel superimposed electrical signal and the emission time of the laser light emitting signal.

Correspondingly, step 505 specifically includes: respectively calculating first distance values between the laser radar and the target object in the corresponding receiving field angles according to the first time differences calculated by the first timing paths; and calculating a second distance value between the laser radar and the target object within the total receiving field angle according to the second time difference calculated by the second timing path. And calculating a third distance value between the laser radar and the target object within the total receiving view angle according to the third time difference calculated by each third timing path.

The ranging methods of the laser radar provided in the fourth embodiment and the ranging methods provided in the fifth embodiment are executed by the apparatus shown in fig. 4, and the implementation principle and the technical effect are similar, and are not described herein again.

In order to better explain the distance measuring method of the laser radar provided by the embodiment, the distance measuring device adopting the laser radar method comprises five APD (avalanche photo diode) units in an array, wherein the APD units in the array are five APD units and comprise five APD pixel elements; the amplifying circuit unit comprises five first amplifying circuit paths, one second amplifying circuit path and one third amplifying circuit path. The time discrimination unit comprises five first time discrimination paths, a second time discrimination path and a third time discrimination path; the ranging method of the laser radar according to the sixth embodiment of the present invention is described with reference to the timing unit including five first timing paths, one second timing path, and one third timing path. As shown in fig. 9, the ranging method of the laser radar according to the seventh embodiment includes the following steps:

step 901, the laser emitting unit emits a laser light emitting signal under the control of the main control unit.

Step 902, the receiving mirror group converges the laser diffuse reflection signal reflected by the laser light-emitting signal on the target object to five APD pixels of the five array APD units.

And step 903, converting the laser diffuse reflection signals in the corresponding receiving field angle into electric signals by the five APD pixels in the five-array APD unit.

And 904, amplifying the corresponding electric signals by five first amplifying circuit paths in the amplifying circuit unit to form amplified electric signals, simultaneously superposing the electric signals corresponding to the five APD pixels by one second amplifying circuit path, amplifying the superposed electric signals to form amplified total superposed electric signals, and simultaneously superposing the electric signals of at least two corresponding APD pixels by one third amplifying circuit path and amplifying the superposed electric signals to form amplified multi-channel superposed electric signals.

In step 905, five first time discrimination paths in the time discrimination unit discriminate the output time of the corresponding amplified electrical signal, one second time discrimination path discriminates the output time of the amplified total superimposed electrical signal, and one third time discrimination path discriminates the output time of the corresponding amplified multi-channel superimposed electrical signal.

Step 906, five first timing paths in the timing unit calculate a first time difference between the output time of the corresponding amplified electrical signal and the emission time of the laser luminescent signal, one second timing path calculates a second time difference between the output time of the amplified total superimposed electrical signal and the emission time of the laser luminescent signal, and one third timing path calculates a third time difference between the output time of the corresponding amplified multi-path superimposed electrical signal and the emission time of the laser luminescent signal.

Step 907, the main control unit calculates first distance values between the laser radar and the target object within corresponding receiving field angles according to the five first time differences, and meanwhile, if the main control unit determines that the first distance value corresponding to a certain first amplifying circuit path is not output, the main control unit outputs a second distance value as the first distance value of the certain first amplifying circuit path, or when the first distance value corresponding to the certain first amplifying circuit path is not output, acquires a target third distance value based on an APD pixel connected with the first amplifying circuit path, and outputs the target third distance value as the first distance value of the certain first amplifying circuit path; and when the first distance value corresponding to a certain first amplifying circuit path is not output and the third distance value corresponding to a third amplifying circuit path connected with an APD pixel of the first amplifying circuit path is not output, outputting the second distance value as the first distance value of the certain first amplifying circuit path.

EXAMPLE seven

The seventh embodiment of the present invention provides a laser radar, where the laser radar provided in this embodiment includes the ranging device of the laser radar provided in the first embodiment or the second embodiment of the present invention.

The implementation principle and technical effect of the ranging device of the laser radar are similar to those of the ranging device of the laser radar provided in the first embodiment or the second embodiment of the present invention, and are not described in detail herein.

Optionally, the laser radar may be a mechanical laser radar, or may be another type of laser radar, which is not limited in this embodiment.

Although the subject matter has been described in language specific to structural features and/or methodological acts, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

Claims

1. A ranging apparatus for a laser radar, comprising: a laser emission unit and an APD receiving circuit;

2. The apparatus of claim 1, wherein the amplification circuit unit further comprises: a second amplifying circuit path;

3. The apparatus of claim 1, wherein the amplification circuit unit further comprises: at least one third amplification circuit path;

each third amplifying circuit channel is used for superposing the electric signals of at least two corresponding APD pixels and amplifying the superposed electric signals to form amplified multi-channel superposed electric signals;

4. The device of claim 1, wherein the laser emitting unit is configured to emit a laser light emitting signal under the control of the main control unit;

the receiving mirror group is used for converging laser diffuse reflection signals reflected by the laser light-emitting signals on a target object to each APD pixel of the APD unit array;

and each APD pixel is used for converting the laser diffuse reflection signals in the corresponding receiving field angle into electric signals.

5. The apparatus of claim 3, wherein the APD receive circuit further comprises: a time discrimination unit;

6. The apparatus of claim 5, wherein each of the first time discrimination paths is configured to discriminate an output time of the corresponding amplified electrical signal;

7. The apparatus of claim 3, wherein the APD receive circuit further comprises: a timing unit;

8. The apparatus of claim 7, wherein each of the first timing paths is configured to calculate a first time difference between an output time of the corresponding amplified electrical signal and an emission time of the laser emission signal;

9. A ranging method of a laser radar, comprising:

the receiving mirror group converges the laser diffuse reflection signal reflected by the laser luminescent signal on the target object to each APD pixel of the array APD unit;

10. The method of claim 9, wherein each APD pixel element in the array APD cell, after converting the laser diffuse reflection signal in the corresponding receiving field angle to an electrical signal, further comprises:

11. The method of claim 9, wherein each APD pixel element in the array APD cell, after converting the laser diffuse reflection signal in the corresponding receiving field angle to an electrical signal, further comprises:

12. The method of claim 11, further comprising:

each first time discrimination path discriminates the output time of the corresponding amplified electrical signal;

13. The method of claim 12, further comprising:

14. A lidar, comprising: the lidar ranging device according to any one of claims 1 to 8.