LIDAR DEVICE AND METHOD OF OPERATION THEREOF

Abstract

To provide a lidar device and its operation method in which high video resolution is realized.SOLUTION: In a lidar (LiDAR) device, a plurality of light sources and a plurality of light detection elements are included, and based on first detection information detected by a light detection element of any one of the plurality of light detection elements, crosstalk which causes an error in the ToF operation is removed from second detection information detected by at least one of the remaining light detection elements, then a distance to a target body is calculated and data processing for position and shape analysis of the target body is performed.SELECTED DRAWING: Figure 9

Description

[Technical field]

[0001] The present disclosure relates to LIDAR devices and methods of operation. [Background technology]

[0002] LiDAR (light detection and ranging) systems are used in a variety of fields, such as aerospace, geology, three-dimensional maps, automobiles, robots, and drones.

[0003] The LIDAR device uses the time of flight (ToF) method as a basic operating principle. For example, the LIDAR device can transmit light toward an object, receive it through a sensor, and measure the time of flight using a high-speed electrical circuit. The LIDAR device can also calculate the distance to the object from the time of flight, and generate a depth image of the object using the calculated distance for each position of the object.

[0004] Meanwhile, in order to realize high image resolution within a given frame time, the LIDAR device may be equipped with multiple light sources and multiple photodetection elements that receive light irradiated from the multiple light sources. In such a case, however, an error in ToF calculation may occur if any one photodetection element receives light irradiated from two light sources.

[0005] Therefore, a technique is required to distinguish the received signal from the detected information detected by the photodetector elements and to eliminate crosstalk. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] U.S. Pat. No. 10,063,849 Summary of the Invention [Problem to be solved by the invention]

[0007] The problem to be solved by the present invention is to provide a LIDAR device and an operating method thereof capable of eliminating crosstalk. The technical problem to be solved by the present invention is not limited to the above-mentioned technical problem, and other technical problems may be inferred from the following embodiments. [Means for solving the problem]

[0008] According to one aspect, a LiDAR device may include an optical transmitter including a plurality of light sources and irradiating light generated by the plurality of light sources toward an object; an optical receiver including a plurality of optical detection elements that detects reflected light of the light irradiated toward the object and removes crosstalk from second detection information detected by at least one of the remaining optical detection elements based on first detection information detected by any one of the plurality of optical detection elements; and a processor that acquires information related to the object using the detection information from which the crosstalk has been removed.

[0009] In addition, the optical receiving unit includes a first optical detection element that receives a first light irradiated toward the target from a first light source among the plurality of light sources via a first path and outputs the first detection information related to the first light, and a second optical detection element that receives a second light irradiated toward the target from a second light source different from the first light source via a second path, the crosstalk occurring when the first light irradiated toward the target from the first light source is further received by the second optical detection element via a third path different from the first path, the second optical detection element being able to output the second detection information related to the first light and the second light when the crosstalk occurs.

[0010] In addition, the optical receiving unit may further include a first detection signal conversion unit that converts the first detection information output by the first optical detection element into a first pulse signal having a pulse waveform, and a second detection signal conversion unit that converts the second detection information output by the second optical detection element into a second pulse signal having a pulse waveform.

[0011] In addition, the optical receiving unit may further include a crosstalk removal unit that determines an earlier one of a first reception time point of the first light detected by the first optical detection element and a second reception time point of the first light detected by the second optical detection element as a crosstalk removal start time point, and removes pulses included in the second pulse signal that are located between the removal start time point and a preset masking pulse width.

[0012] Moreover, the masking pulse width is set to be wider than the pulse width of the first light emitted by the optical transmitter.

[0013] Also, the optical transmitter may further include a beam steering element configured to adjust a direction of the light generated by the plurality of light sources so that the light scans the target object.

[0014] In addition, the beam steering element can adjust the aiming direction of the light by mechanical rotation.

[0015] The optical receiving section may also include a plurality of counters that count the time of flight (ToF) of light detected by each of the plurality of optical detection elements.

[0016] In addition, the processor can calculate the distance to the object based on the time of flight (ToF) of the light detected by the optical receiving unit, and perform data processing for analyzing the position and shape of the object.

[0017] According to another aspect, a method of operating a LIDAR device may include a step of irradiating light generated by a plurality of light sources toward an object; detecting reflected light of the light irradiated toward the object via a plurality of optical detection elements; removing crosstalk from second detection information detected by at least one of the remaining optical detection elements based on first detection information detected by any one of the plurality of optical detection elements; and acquiring information related to the object using the detection information from which the crosstalk has been removed.

[0018] The detecting step may further include a step of receiving, via a first path, a first light irradiated toward the target from a first light source of any one of the plurality of light sources using a first light detection element, and outputting the first detection information related to the first light, and a step of receiving, via a second path, a second light irradiated toward the target from a second light source different from the first light source using a second light detection element, wherein the crosstalk occurs when the first light irradiated toward the target from the first light source is further received by the second light detection element via a third path different from the first path, and when the crosstalk occurs, the step of outputting the second detection information related to the first light and the second light using the second light detection element.

[0019] In addition, the detecting step may further include a step of converting the first detection information output by the first optical detection element into a first pulse signal having a pulse wave shape, and a step of converting the second detection information output by the second optical detection element into a second pulse signal having a pulse wave shape.

[0020] The removing step may include determining an earlier one of a first reception time point of the first light detected by the first light detection element and a second reception time point of the first light detected by the second light detection element as a removal start time point of the crosstalk, and removing pulses included in the second pulse signal that are located between the removal start time point and a preset masking pulse width.

[0021] Moreover, the masking pulse width is set to be wider than the pulse widths of the first light and the second light.

[0022] The acquiring step may also include counting a time of flight (ToF) of light detected by each of the plurality of light detecting elements.

[0023] The acquiring step may further include calculating a distance to the object based on the time of flight (ToF) and performing data processing for analyzing a position and a shape of the object. Effect of the Invention

[0024] Even when the LIDAR device of the present invention is equipped with multiple light sources and multiple light detecting elements that receive light irradiated from the multiple light sources in order to realize high image resolution within a given frame time, it is possible to eliminate crosstalk between the multiple light detecting elements and more accurately analyze the position and shape of an object. [Brief description of the drawings]

[0025] [Figure 1] FIG. 1 is a block diagram showing a configuration of a LIDAR device according to an embodiment. [Diagram 2] 1 illustrates an exemplary arrangement and operation of an optical transmitter and receiver of a LIDAR device in accordance with one embodiment. [Figure 3A] 1 is a diagram illustrating an example of a beam steering element provided in a LIDAR device according to an embodiment, and a principle of point scanning using the beam steering element; [Figure 3B] 1 is a diagram illustrating an example of a beam steering element provided in a LIDAR device according to an embodiment, and a principle of point scanning using the beam steering element; [Figure 4] FIG. 2 is a block diagram illustrating an exemplary configuration of a processor included in a LIDAR device according to one embodiment. [Diagram 5] 5 is a diagram showing an example of a target region partitioned by the processor of FIG. 4; [Figure 6] 1 is a diagram illustrating an exemplary circuit configuration of an optical receiver provided in a LIDAR device according to an embodiment. [Figure 7A] 11 is a diagram for explaining detection information detected by an optical receiving unit when no crosstalk occurs; [Figure 7B]11 is a diagram for explaining detection information detected by an optical receiving unit when no crosstalk occurs; [Figure 8A] 11 is a diagram for explaining detection information detected by an optical receiving unit when crosstalk occurs; [Figure 8B] 11 is a diagram for explaining detection information detected by an optical receiving unit when crosstalk occurs; [Figure 9] 1 is a diagram illustrating an internal block diagram of an optical receiving unit provided in a LIDAR device according to an embodiment. [Figure 10A] 10 is a diagram for explaining a method of identifying and removing crosstalk using the first detection information and the second detection information of FIG. 9; [Figure 10B] 10 is a diagram for explaining a method of identifying and removing crosstalk using the first detection information and the second detection information of FIG. 9; [Figure 11] 13 is a diagram showing an example of an experiment in which crosstalk occurs; [Figure 12] 13 is a diagram showing an experimental example in which crosstalk is removed through a masking pulse. [Figure 13] 1 is a flowchart illustrating a method of operating a LIDAR device according to one embodiment. [Figure 14] 11 is a flowchart illustrating a method for detecting reflected light via a plurality of light detection elements. [Figure 15] 11 is a diagram for explaining a method for identifying crosstalk in detection information detected by a plurality of photodetection elements. [Figure 16] 10 is a flowchart illustrating a method for removing crosstalk from detection information detected by a plurality of light detection elements. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] The appearances of phrases such as "in some embodiments" or "in one embodiment" in various places in this specification do not necessarily refer to the same embodiment.

[0027] Some embodiments of the present disclosure are also illustrated by functional block configurations and various processing steps. Some or all of such functional blocks may be embodied by various numbers of hardware and / or software configurations performing specific functions. For example, the functional blocks of the present disclosure may be embodied by one or more microprocessors or by circuit configurations for a given function. For example, the functional blocks of the present disclosure may be embodied by various programming or scripting languages. The functional blocks may be embodied by algorithms executed by one or more processors. The present disclosure may also employ conventional techniques for electronic configuration, signal processing, and / or data processing. Terms such as "mechanism," "element," "means," and "configuration" are used generically and are not limited to mechanical and physical configurations.

[0028] In addition, the connecting lines or connecting members between components shown in the drawings are merely illustrative of functional connections and / or physical or circuit connections, and in an actual device, connections between components may be represented by various alternative or additional functional connections, physical connections, or circuit connections.

[0029] FIG. 1 is a block diagram showing a configuration of a LiDAR (light detection and ranging) device according to an embodiment.

[0030] 1, the LIDAR device 1000 may include an optical transmitter 100 that scans light onto an object OBJ, an optical receiver 200 that detects reflected light of light irradiated from the optical transmitter 100 onto the object OBJ, and a processor 300 that controls the optical transmitter 100 and the optical receiver 200. However, only components related to the present embodiment are illustrated in the LIDAR device 1000 illustrated in FIG 1. Therefore, it will be obvious to those skilled in the art that the LIDAR device 1000 may further include other general-purpose components in addition to the components illustrated in FIG 1.

[0031] The optical transmitter 100 may include a light source section 110 including a plurality of light sources (light source 1, light source 2, . . . , light source N) and a beam steering element 180.

[0032] In one embodiment, the arrangement and operation of the light source unit 110 and the beam steering element 180 are determined so that light from each of the multiple light sources passes through the beam steering element 180 and scans the object OBJ at different irradiation angles. In another embodiment, the arrangement and operation of the light source unit 110 and the beam steering element 180 are determined so that light from each of the multiple light sources passes through the beam steering element 180 and scans the object OBJ at the same irradiation angle.

[0033] The light source of the light source unit 110 may emit light used for analyzing the position and shape of the object OBJ. The light source unit 110 may generate and emit light of a predetermined wavelength, for example, light of a wavelength band suitable for analyzing the position and shape of the object OBJ, for example, light of an infrared wavelength band. If the infrared light band is used, mixing with natural light in the visible light range including sunlight may be prevented. However, the light is not necessarily limited to the infrared band, and light of various wavelength bands may be emitted.

[0034] The light source unit 110 may include a light source such as a laser diode (LD), an edge emitting laser, a vertical-cavity surface emitting laser (VCSEL), a distributed feedback laser, a light emitting diode (LED), or a super luminescent diode (SLD). The light source unit 110 may generate and irradiate light of a plurality of different wavelength bands. The light source unit 110 may generate and irradiate pulsed light or continuous light.

[0035] The light sources of the light source unit 110 can irradiate light toward the object OBJ under the control of the processor 300. For example, the processor 300 can set an irradiation direction or irradiation angle of light from each light source, and can control the light source unit 110 so that the multiple light sources irradiate light according to the respective set irradiation angles or directions.

[0036] The beam steering element 180 aims the light from the light source unit 110 toward the object OBJ, adjusts the aiming direction in time sequence, and scans the entire object OBJ with the point light emitted from the light source unit 110. The beam steering element 180 may be a scanning mirror or an optical phased array.

[0037] The light receiving unit 200 may include a plurality of pixelated regions capable of detecting reflected light from the object OBJ by dividing the reflected light into different regions according to positions.

[0038] As shown in the figure, the light receiving unit 200 may include a detector array 220 divided into a plurality of pixels PX1, PX2, ..., PXm. A light detection element may be disposed in each of the plurality of pixels PX1, PX2, ..., PXm. In other words, the light detection elements 222 form pixels PX1, PX2, ..., PXm that are divided according to their positions in the detector array 220, and each pixel PX1, PX2, ..., PXm can detect the reflected light from the object OBJ and the light irradiated from the light source unit 110 separately.

[0039] The optical receiving section 200 may include a circuit section 240 for measuring (counting) the time of flight (ToF) of the light detected by each of the multiple optical detection elements 222, and may further include optical elements for focusing light from the object OBJ at a predetermined pixel.

[0040] The light detection elements 222 are sensors capable of sensing light, and may be, for example, light receiving elements that generate an electrical signal in response to optical energy. The type of the light receiving elements is not particularly limited.

[0041] As described above, the LIDAR device 1000 according to an embodiment uses a point scanning method, and therefore the intensity of light received by the light detection element 222 is lower than other methods, for example, a flash method. Therefore, an avalanche photo diode (APD) or a single photon avalanche diode (SPAD) having high sensing sensitivity may be adopted as the light detection element 222. Depending on whether the light detection element 222 of the optical receiver 200 includes an avalanche photodiode (APD) or a single photon avalanche diode (SPAD), specific circuit configurations such as an analog front end (AFE) and a time to digital converter (TDC) may differ.

[0042] The processor 300 may perform signal processing for acquiring information related to the object OBJ using the light detected by the optical receiving unit 200. For example, the processor 300 may determine a distance to each position of the object OBJ based on the time of flight (ToF) of the light reflected from the object OBJ, and perform data processing for analyzing the position and shape of the object OBJ.

[0043] The information analyzed by the processor 300, i.e., information related to the shape and position of the object OBJ, may be transmitted to other units and utilized. For example, such information may be transmitted to a control unit of an autonomous driving device such as an unmanned automobile or drone in which the LIDAR device 1000 is employed. In addition, such information may be utilized in smartphones, mobile phones, personal digital assistants (PDAs), laptops, personal computers (PCs), various wearable devices, and other mobile or non-mobile computing devices.

[0044] The processor 300 may also control the overall operation of the LIDAR device 1000, including controlling the optical transmitting unit 100 and the optical receiving unit 200. The processor 300 may divide an area of ​​the object OBJ in consideration of the number of light sources provided in the light source unit 110, and may generate a control signal for the beam steering element 180 and apply it to the beam steering element 180 so that the entire divided area is scanned by the beam steering element 180.

[0045] The processor 300 can also control the operations of the light source unit 110 and the optical receiving unit 200. For example, the processor 300 can perform power supply control, on / off control, and generation control of a pulse wave (PW) or a continuous wave (CW) for the light source unit 110. The processor 300 can also apply control signals to each of the optical detection elements 222 of the optical receiving unit 200.

[0046] In one embodiment, the processor 300 may group the light detection elements 222 into a plurality of groups, and the light receiving unit 200 may separately detect the light irradiated from the light source unit 110 for each group.

[0047] The processor 300 may set the number of light detection elements 222 included in each group based on the surrounding environment. For example, when the ambient illumination of the light receiving unit 200 is a first illumination, the processor 300 may group the light detection elements 222 so that each group includes a first number of light detection elements 222, and when the ambient illumination of the light receiving unit 200 is a second illumination lower than the first illumination, the processor 300 may group the light detection elements 222 so that each group includes a second number of light detection elements 222 greater than the first number. The light detection elements 222 may output detection signals by superimposing them for each group, and the processor 300 may detect the light irradiated from the light source unit 110 separately for each group.

[0048] The LIDAR device 1000 may also include memory in which programs for operations performed by the processor 300 and other data are stored.

[0049] The memory is hardware that stores various data processed within the LIDAR device 1000. For example, the memory can store data that has been processed by the LIDAR device 1000 and data to be processed. The memory can also store applications, drivers, etc. that are operated by the LIDAR device 1000.

[0050] The memory may include random access memory (RAM), such as dynamic random access memory (DRAM) and static random access memory (SRAM), read only memory (ROM), electrically erasable programmable read only memory (EEPROM), compact disc read only memory (CD-ROM), Blu-ray or other optical disk storage, hard disk drive (HDD), solid static disk drive (SSD), or flash memory, and may also include other storage devices external to the lidar device 1000 that may be accessed by the lidar device 1000.

[0051] FIG. 2 illustrates an exemplary arrangement and operation of the optical transmitter and receiver of a LIDAR device according to one embodiment.

[0052] Referring to FIG. 2, a LIDAR device 1000 according to one embodiment employs an optical transmitter 100 that uses a point scanning method to scan a point light onto an object OBJ, and can scan the entire area of ​​the object OBJ through multiple light sources.

[0053] For example, as shown in Fig. 2, the first light source 110a and the second light source 110b irradiate light to the beam steering element 180 at different angles, and the two irradiation lines L1, L2 steered by the beam steering element 180 have an angle of θ between them. The angle θ is sufficient if the light can be detected by distinguishing the reflected light from the object OBJ at different pixels in the detector array 220. The angle is determined by the resolution of the detector array 220 constituting the optical receiving unit 200, as well as the performance of additional optical elements included in the optical receiving unit 200. For example, the angle θ may be about 1° or more.

[0054] The times for which the first light source 110a and the second light source 110b irradiate light may be the same, but are not limited to this, and the times T1 and T2 are also different. The time difference between T1 and T2 may be within 1 μs, for example.

[0055] Each of the illumination lines L1 and L2 is steered by actuation of the beam steering element 180 to scan a predetermined field of view (FOV) range including the object. The light from the object is directed to different pixels of the detector array 220, and as shown, a lens 230 may be further provided to focus the light on the pixels of the detector array 220.

[0056] Each pixel of the detector array 220 is connected to a circuit element for time-of-flight (ToF) calculation, and a first time-of-flight ToF #1 and a second time-of-flight ToF #2 can be derived through a predetermined calculation.

[0057] The LIDAR device 1000 according to an embodiment uses a point scanning method in which a point light is scanned onto an object OBJ by the optical transmitter 100, and has a resolution limit due to the speed of light. For example, the number of pieces of information (point cloud) that can be acquired for an object OBJ within a given frame time, i.e., a given reference time for forming one frame of an image for the object OBJ, is limited, thereby determining the resolution limit. In other words, if one tries to maintain the spatial resolution and expand the field of view (FOV), the frame time becomes longer, and such a performance degradation is more pronounced as the distance to the object OBJ becomes longer.

[0058] In order to improve upon such a resolution limit, the LIDAR device 1000 according to the present disclosure can use multiple light sources. Also, in one embodiment, the multiple light sources can be maintained at different illumination angles. As a result, the resolution can be increased in proportion to the number of multiple light sources provided in the LIDAR device 1000.

[0059] 3A and 3B are diagrams illustrating an example of a beam steering element provided in a LIDAR device according to an embodiment and the principle of point scanning using the beam steering element.

[0060] Referring to FIG. 3A, the scanning mirror is mechanically rotated to adjust the direction of the reflecting surface, and the incident light L i The steering direction of the incident light L is adjusted according to the rotation angle. i The direction in which L is steered is S1 , L S2 , L S3 The scanning mirror rotation is illustrated as being uniaxial, but is not limited thereto, and may be biaxial, i.e., may be rotated about two rotation axes.

[0061] The scanning mirror is also illustrated as having one reflective surface, but this is by way of example only, and multiple mirror elements may be arranged and their respective orientations adjusted to reflect the incoming light L. i It is also possible to steer the object OBJ in a direction toward the object OBJ.

[0062] Referring to FIG. 3B, the optical phase array OPA may include a number of channels CH1, CH2, .... In each of the channels CH1, CH2, ..., the incident light L i A phase change value is set to change the phase of the incident light L i can be steered and the direction in which the person comes to work can be adjusted.

[0063] Each of the multiple channels CH1, CH2, ... of the optical phase array OPA receives the incident light L i The phase change value for may be electrically tunable.

[0064] Or, the optical phase array OPA is a iSuch an optical waveguide may include a phase delay element provided in each of the branched paths, and the length of each path and / or the degree of phase delay in the phase delay element of each path may be adjusted to adjust the incident light L i The direction in which the light is emitted can be adjusted by steering the light.

[0065] The optical phase array (OPA) detects the incident light L i The combination of phase changes in each channel steers the light in a direction determined by the combination of phase changes that occur in each channel. i The direction in which the beam is steered is L S1 , L S2 , L S3 can be adjusted in that order.

[0066] FIG. 4 is a block diagram showing an example configuration of a processor included in a LIDAR device according to one embodiment, and FIG. 5 shows an example of a target area partitioned by the processor of FIG. 4 .

[0067] 4 and 5, the processor 300 may include an object region defining unit 330 and an analysis unit 350. Code for executing the object region defining unit 330 and the analysis unit 350 may be stored in a memory included in the LIDAR device 1000, and such code may be executed by the processor 300.

[0068] The object region partition unit 330 may divide a predetermined field of view (FOV) range including the object OBJ into the same number as the number of light sources provided in the LIDAR device 1000. Fig. 5 shows an example in which the field of view (FOV) range is divided into six when the number of light sources is six. However, this is merely an example, and the number of divisions and the divided form are not limited thereto.

[0069] The target area partition unit 330 can generate a scanning control signal and apply it to the optical transmitting unit 100 so that the divided area is scanned by the optical transmitting unit 100. The scanning control signal is also a rotation drive control signal that controls the rotation direction and rotation angle, for example, when the beam steering element 180 is a scanning mirror as illustrated in FIG.

[0070] The scanning control signal may be a phase control signal applied to each channel when the beam steering element 180 is an optical phase array OPA as illustrated in Fig. 3B, or may be an electrical signal applied to a meta-element constituting each channel, or a phase delay signal for a phase delay element provided in each channel.

[0071] The analysis unit 350 may analyze the position and shape of the object OBJ by taking into consideration the irradiation angle of the light irradiated to the object and the time of flight (ToF) value calculated in consideration of the irradiation angle.

[0072] FIG. 6 shows an exemplary circuit configuration of an optical receiver included in a LIDAR device according to one embodiment.

[0073] Referring to FIG. 6, the optical receiving unit 200 may include a plurality of optical detection elements 222, a crosstalk removal unit 247 that removes crosstalk from light detected by each of the plurality of optical detection elements 222, and a plurality of time counters 249 that measure the time of flight (ToF) of the light from which the crosstalk has been removed.

[0074] The optical receiving unit 200 may include a plurality of current-voltage conversion circuits 241 that convert the current output from each of the multiple optical detection elements 222 into a voltage, a plurality of amplifiers 243 that amplify the voltages converted by each of the multiple current-voltage conversion circuits 241, and a plurality of peak detectors 245 that detect peaks in the signals amplified by the multiple amplifiers 243.

[0075] The light detection elements 222 can detect the light beams L1, L2, and L3 received from the object OBJ and output detection information. The detection information detected by the light detection elements 222 is also transmitted to the processor 300 via the channels ch1, ch2, and ch3.

[0076] Specifically, the multiple light detection elements 222 can individually detect multiple light beams L1, L2, and L3 from the target object and output a current signal.

[0077] The plurality of current-voltage conversion circuits 241 can convert the current signals output from the respective plurality of light detection elements 222 into voltage signals.

[0078] The plurality of amplifiers 243 can amplify the voltage signals converted by the plurality of current-voltage conversion circuits 241, respectively.

[0079] The multiple peak detectors 245 can detect peaks in the voltage signals amplified by the multiple amplifiers 243, respectively. For example, the multiple peak detectors 245 can detect peaks by detecting rising edges and falling edges of the electrical signal. The multiple peak detectors 245 can also detect peaks using a constant fraction discriminator (CFD) method. The multiple peak detectors 245 may further include a comparator, and can convert the detected peaks into pulse signals and output them.

[0080] Meanwhile, the detection information detected by the optical detection element 222 means information related to the light received by the optical detection element 222, and therefore hereinafter, the detection information means at least one of the current signal output by the optical detection element 222, the voltage signal converted by the current-voltage conversion circuit 241, the voltage signal amplified by the amplifier 243, and the pulse signal converted by the comparator.

[0081] The multiple crosstalk removing sections 247 can remove crosstalk from each piece of detection information detected by the multiple light detecting elements 222. The crosstalk removing method of the crosstalk removing section 247 will be described in further detail with reference to FIG.

[0082] The plurality of time counters 249 can measure the time of flight (ToF) of light using the detection information from which crosstalk has been removed. When the pulse signals output from the plurality of peak detectors 245 are input, each of the plurality of time counters 249 can calculate how many periods of a clock signal have been generated from the time point of irradiation of light by the light source, and measure the time of flight (ToF) of light. Also, each of the plurality of time counters 249 can store information related to each measured time of flight (ToF) of light in a register. Each of the plurality of time counters 249 can be embodied by a TDC.

[0083] The measurement results measured by the multiple time counters 249 are transmitted to the processor 300, which can use them to perform data processing to analyze information related to the object, such as the position and shape of the object.

[0084] 7A and 7B are diagrams for explaining detection information detected by the optical receiving unit when no crosstalk occurs.

[0085] 7A and 7B, a first light source 110a and a second light source 110b may generate a first light L1 and a second light L2, respectively. The first light source 110a and the second light source 110b may irradiate the first light L1 and L2, respectively, toward an object OBJ in order to analyze the position and shape of the object OBJ.

[0086] In one embodiment, the LIDAR device 1000 may further include a beam steering element 180 that adjusts the aiming direction of the first light source 110a and the second light source 110b, and the beam steering element 180 can cause the point light output from the first light source 110a and the second light source 110b to scan the entire object OBJ.

[0087] The first light L1 generated by the first light source 110a and irradiated toward the object OBJ is also transmitted to the first light detection element 222a via a first path (path 1). The second light L2 generated by the second light source 110b and irradiated toward the object OBJ is also transmitted to the second light detection element 222b via a second path (path 2).

[0088] The detection information 710 detected by the first optical detection element 222a and the detection information 720 detected by the second optical detection element 222b are as shown in FIG. 7B.

[0089] The optical receiving unit 200 can calculate the time of flight ToF #1 of the first light L1 based on the detection information 710 detected by the first optical detection element 222a. Also, the optical receiving unit 200 can calculate the time of flight ToF #2 of L2 based on the detection information 720 detected by the second optical detection element 222b. The processor 300 can analyze the position and shape of the object OBJ based on the time of flight ToF #1 of the first light L1 and the time of flight ToF #1 of L2.

[0090] 7A and 7B, when no crosstalk occurs between the optical detection elements, each optical detection element receives only one light, so the LIDAR device 1000 can analyze the position and shape of the object OBJ by calculating the time of flight (ToF) of light based on the detection information detected by each optical detection element. However, when crosstalk occurs between the optical detection elements, if the time of flight (ToF) of light is calculated based on the detection information detected by each optical detection element, a significant error occurs in the analysis of the position and shape of the object OBJ.

[0091] 8A and 8B are diagrams illustrating detection information detected by an optical receiving unit when crosstalk occurs.

[0092] 8A and 8B, as in FIGS. 7A and 7B, the first optical detection element 222a receives the first light L1 irradiated from the first light source 110a toward the object OBJ via a first path (path 1), and the second optical detection element 222b receives the first light L2 irradiated from the second light source 110b toward the object OBJ via a second path (path 2).

[0093] Meanwhile, the second optical detection element 222b can receive the first light L1 irradiated from the first light source 110a toward the object OBJ via a third path (path 3) different from the first path (path 1) due to the shape of the object OBJ. Since the second optical detection element 222b further receives the first light L1 in addition to the desired light L2, the first light L1 may correspond to crosstalk in the detection information detected by the second optical detection element 222b.

[0094] FIG. 8B is a diagram illustrating detection information 810 detected by the first optical detection element 222a and detection information 820 detected by the second optical detection element 222b.

[0095] 8B, it can be seen that the detection information 820 detected by the second optical detection element 222b includes a pulse signal similar to the pulse signal detected by the first optical detection element 222a. In the detection information 820 detected by the second optical detection element 222b, the pulse signal similar to the pulse signal detected by the first optical detection element 222a is also crosstalk.

[0096] Since the crosstalk detected by the second light detection element 222b is caused by the first light L1 generated by the first light source, if the second light detection element 222b misidentifies the first light L1 as L2 and outputs detection information, the processor 300 will not be able to accurately analyze the position and shape of the object OBJ. In the following, a method for removing crosstalk from the detection information detected by the light detection elements 222a and 222b will be described.

[0097] Note that although Figures 8A and 8B only illustrate the crosstalk between the first light detection element 222a and the second light detection element 222b caused by the first light source 110a and the second light source 110b, the present disclosure is not limited thereto, and in one embodiment, the number of light sources may be increased and the number of light detection elements in which crosstalk occurs may also be increased.

[0098] FIG. 9 is a diagram illustrating an internal block diagram of an optical receiving unit provided in a LIDAR device according to an embodiment.

[0099] Referring to FIG. 9, the optical receiving unit 200 may include a detector array 220 in which a plurality of optical detection elements 222 are arranged, a signal conversion unit 260 that converts light detected by the plurality of optical detection elements 222 into a detection signal for time-of-flight (ToF) calculation, and a crosstalk elimination unit 280 that removes crosstalk from the detection signal output by the signal conversion unit 260.

[0100] A plurality of light detection elements 222 are arranged in the detector array 220 and can receive reflected light of the light emitted by the light transmitting unit 100 toward the object OBJ.

[0101] In one embodiment, the plurality of light detecting elements 222 are also first light detecting elements 222a and second light detecting elements 222b.

[0102] The first light detection element 222a receives the first light irradiated from the first light source 110a toward the object OBJ via a first path (path 1), and the second light detection element 222b receives the second light irradiated from a second light source 110b different from the first light source 110a toward the object OBJ via a second path (path 2). Meanwhile, crosstalk also occurs when the first light irradiated from the first light source 110a toward the object OBJ is further received by the second light detection element 222b via a third path (path 3) different from the first path (path 1).

[0103] The first light detection element 222a can output first detection information related to the first light, and the second light detection element 222b can output second detection information related to the first light and the second light.

[0104] The first detection information detected by the first light detection element 222a and the second detection information detected by the second light detection element 222b are also transmitted to the processor 300 via the first channel (channel A) and the second channel (channel B), respectively.

[0105] Specifically, when the first optical detection element 222a receives a first light, it can output a first current signal 910 corresponding to the first light. When the second optical detection element 222b receives the first light and the second light, it can output a second current signal 920 corresponding to the first light and the second light. The second current signal 920 output by the second optical detection element 222b also includes crosstalk due to the first light.

[0106] The first current signal 910 is also input to the signal conversion section 260 as first detection information. In addition, the second current signal 920 is also input to the signal conversion section 260 as second detection information.

[0107] The signal conversion unit 260 can convert the current signals output by the multiple light detection elements 222 into pulse signals for time-of-flight (ToF) calculation. The signal conversion unit 260 includes the current-voltage conversion circuit 241, the amplifier 243, the peak detector 245, and the comparator shown in FIG.

[0108] To convert the current signal into a pulse signal, the signal conversion unit 260 may include a plurality of detection signal conversion units respectively coupled to the plurality of light detection elements 222. In one embodiment, the signal conversion unit 260 may include a first detection signal conversion unit 261 coupled to the first light detection element 222a and a second detection signal conversion unit 262 coupled to the second light detection element 222b.

[0109] The first detection signal converter 261 may convert the first current signal 910 output by the first optical detection element 222a into a first voltage signal and amplify the first voltage signal. The first detection signal converter 261 may also detect a peak in the amplified first voltage signal, convert the detected peak into a first pulse signal 930, and output the first detection signal. Similarly, the second detection signal converter 262 may convert the second current signal 920 output by the second optical detection element 222b into a second voltage signal, amplify the second voltage signal, detect a peak in the amplified second voltage signal, convert the amplified second voltage signal into a second pulse signal 940, and output the second pulse signal 940. The second pulse signal 940 output by the second detection signal converter may still include crosstalk due to the first light.

[0110] The first pulse signal 930 is also input to the crosstalk elimination section 280 as first detection information. The second pulse signal 940 is also input to the crosstalk elimination section 280 as second detection information.

[0111] On the other hand, the signal conversion unit 260 can allow the detection information to be shared among a plurality of channels.

[0112] Specifically, any one of the plurality of detection signal converters can provide detection information to the remaining channels excluding its own channel.

[0113] In one embodiment, the first detection signal conversion unit 261 may transmit the first pulse signal 930 to the second masking unit 282 arranged in the second channel (channel B). Also, the second detection signal conversion unit 262 may transmit the second pulse signal 940 to the first masking unit 281 arranged in the first channel (channel A). The shared pulse signal is also used for identifying and removing crosstalk.

[0114] The crosstalk removal unit 280 may include a plurality of masking units that identify crosstalk in the pulse signal output by the signal conversion unit 260 and mask the identified crosstalk.

[0115] In one embodiment, the crosstalk removal unit 280 may include a first masking unit 281 connected to the first detection signal conversion unit 261 and a second masking unit 282 connected to the second detection signal conversion unit 262 .

[0116] The crosstalk elimination unit 280 may calculate whether crosstalk is included in the pulse signal output from the signal conversion unit 260. In one embodiment, the crosstalk elimination unit 280 may determine whether crosstalk is included in the detection information based on at least one of the number of pulses included in the pulse signal and the time points at which the pulses are received.

[0117] The determination as to whether the detected information contains crosstalk is also made in each masking section included in the crosstalk canceller 280 .

[0118] When the crosstalk elimination unit 280 calculates that the detection information includes crosstalk, the crosstalk elimination unit 280 can identify the crosstalk in the pulse signal. To this end, the crosstalk elimination unit 280 can use the pulse signal provided by the signal conversion unit 260.

[0119] In FIG. 9, the second masking unit 282 may further receive a second pulse signal 940 from the second detection signal conversion unit 262. The second masking unit 282 may determine a pulse corresponding to a pulse included in the first pulse signal 930 among the pulses included in the second pulse signal 940 as crosstalk. The second masking unit 282 may identify crosstalk in the second pulse signal 940 based on the pulse included in the first pulse signal 930. The second masking unit 282 may identify crosstalk in the second pulse signal 940 based on at least one of a receiving time point, a pulse width, and a pulse size of the pulse included in the first pulse signal 930. Since the pulse included in the first pulse signal 930 is generated when the first optical detection element 222a receives the first light, this also means that the receiving time point of the pulse included in the first pulse signal 930 is the same as the first receiving time point of the first light received by the first optical detection element 222a. Similarly, since the pulse included in the second pulse signal 940 occurs when the second optical detection element 222b receives the first light, this also means that the reception time of the pulse included in the second pulse signal 940 is the same as the second reception time of the first light received by the second optical detection element 222b.

[0120] In one embodiment, the second masking unit 282 may determine that a pulse received between a time point that is a predetermined time point earlier than the first reception time point of the first light included in the first pulse signal 930 and a time point that is a predetermined time point later than the first reception time point of the first light included in the first pulse signal 930 is crosstalk caused by the first light.

[0121] The crosstalk canceller 280 can identify the crosstalk in the detection information and then cancel the identified crosstalk.

[0122] 9, the second masking unit 282 may determine a crosstalk removal start time. The second masking unit 282 may compare a first reception time of the first light detected by the first light detection element with a second reception time of the first light detected by the second light detection element. The second masking unit 282 may determine the earlier of the first reception time and the second reception time as a removal start time for removing crosstalk.

[0123] The second masking unit 282 can remove pulses that are located between the removal start time and a preset masking pulse width among the pulses included in the second pulse signal 940. At this time, the masking pulse width is set to be wider than the pulse width of the light irradiated by the optical transmitting unit 100. The method of identifying and removing crosstalk will be described in further detail with reference to Figures 10A and 10B.

[0124] When the detection information includes crosstalk, the crosstalk removal unit 280 can remove the crosstalk and output the resultant information. The information output by the crosstalk removal unit 280 can be called output information.

[0125] Meanwhile, the plurality of time counters 249 may measure the time of flight (ToF) of light using the output information. Also, the processor 300 may obtain information related to the object OBJ based on the time of flight (ToF) of light calculated by the time counter 249. Since the processor 300 obtains information related to the object OBJ using the detection information from which crosstalk has been removed, the LIDAR device 1000 according to the present disclosure may more accurately measure the position, shape, etc. of the object OBJ.

[0126] 9, only the crosstalk occurring between the first optical detection element 222a and the second optical detection element 222b is described, but the present invention is not limited thereto, and the number of optical detection elements in which crosstalk occurs may be increased depending on the shape of the object OBJ. In this case, the second detection information means detection information including crosstalk, and the first detection information means detection information used to remove crosstalk from the second detection information.

[0127] 10A and 10B are diagrams for explaining a method of identifying and removing crosstalk using the first and second detection information of FIG.

[0128] 10A and 10B, the second masking unit 282 may identify the crosstalk included in the second detection information 1020 based on the first reception time point T1 of the first light included in the first detection information 1010.

[0129] Meanwhile, as shown in Figures 8A and 8B, the first light generated by the first light source 110a and irradiated toward the object OBJ is transmitted to the first light detection element 222a via a first path (path 1), and is also transmitted to the second light detection element 222b via a third path (path 3). At this time, the distance of the first path (path 1) may be longer or shorter than the distance of the third path (path 3) depending on the shape of the object OBJ. Therefore, the first reception time T1 of the first light detected by the first light detection element 222a may be longer or shorter than the second reception time T2 of the first light detected by the second light detection element 222b.

[0130] FIG. 10A illustrates an example in which the first reception time T1 precedes the second reception time T2, and FIG. 10B illustrates an example in which the first reception time T1 follows the second reception time T2.

[0131] The second masking unit 282 can determine that the pulse 1030 received between a time (T1-Tp) preceding the first receiving time T1 by a preset time Tp and a time (T1+Tp) following the preset time Tp is crosstalk.

[0132] After identifying the crosstalk, the second masking unit 282 can determine a removal start time Ts of the crosstalk. The second masking unit 282 can compare a first reception time T1 of the first light detected by the first light detection element 222a with a second reception time T2 of the first light detected by the second light detection element. The second masking unit 282 can determine the earlier of the first reception time T1 and the second reception time T2 as a removal start time Ts for removing the crosstalk.

[0133] 10A, when the first receiving time T1 precedes the second receiving time T2, the second masking unit 282 can determine the first receiving time T1 as the removal start time Ts. Conversely, when the first receiving time T1 follows the second receiving time T2, as in FIG. 10B, the second masking unit 282 can determine the second receiving time T2 as the removal start time Ts.

[0134] The second masking unit 282 can remove pulses that are included in the second detection information 1020 and are located between the removal start time point Ts and a preset masking pulse width pw.

[0135] As in FIG. 10A, taking into account the difference td between the first reception time T1 and the second reception time T2 along the path of the first light, the masking pulse width pw is set to be wider than the pulse width of the first light irradiated by the first light source 110a.

[0136] FIG. 11 is a diagram showing an experimental example in which crosstalk occurs.

[0137] Referring to FIG. 11, an example of a first current signal 1110 output by a first photodetector element 222a and a second current signal 1120 output by a second photodetector element 222b is shown.

[0138] The first point 1110a is the point where the first light detecting element 222a receives the first light, and the first light detecting element 222a outputs a current at the first point 1110a that is above a critical level.

[0139] The second point 1120a is a point where the second optical detection element 222b receives the first light, and the current signal output by the second optical detection element 222b to the second point 1120a corresponds to crosstalk. The current signal output by the second optical detection element 222b at the second point 1120a is smaller than the current signal output by the first optical detection element 222a at the first point 1110a, but has a current size equal to or greater than the critical level, and is therefore converted into a pulse signal.

[0140] The third point 1120b is the point where the second optical detection element 222b receives the second light, and the current signal output by the second optical detection element 222b to the third point 1120b must be converted into a pulse signal to calculate the time of flight (ToF) of the second light.

[0141] The second current signal 1120 output by the second optical detection element 222b is converted into a pulse signal and used to calculate the time of flight (ToF) of the second light, but as shown in Fig. 11, the second current signal 1120 contains crosstalk, and the LIDAR device 1000 cannot accurately calculate the time of flight (ToF) of the second light, causing an error in the information of the object OBJ analyzed by the LIDAR device 1000.

[0142] In order to more accurately analyze information related to the object OBJ, the LIDAR device 1000 disclosed herein removes crosstalk from the second detection information detected by the second optical detection element 222b based on the first detection information detected by the first optical detection element 222a.

[0143] FIG. 12 is a diagram showing an experimental example in which crosstalk is removed through a masking pulse.

[0144] Referring to FIG. 12, the LIDAR device 1000 converts the first current signal 1110 output by the first optical detection element 222a and the second current signal 1120 output by the second optical detection element 222b into a first pulse signal and a second pulse signal 1210, respectively.

[0145] The second masking unit 282 identifies crosstalk in the second pulse signal 1210 based on at least one of a pulse receiving time point, a pulse width, and a pulse size included in the first pulse signal.

[0146] The second masking section 282 calculates a removal start time Ts for removing crosstalk, and removes pulses located between the removal start time Ts and a preset masking pulse width pw.

[0147] The second masking unit 282 outputs a masking pulse 1230 having a preset masking pulse width pw from the removal start time Ts, and removes the pulse corresponding to the crosstalk from the second pulse signal 1210 by using the masking pulse 1230. To this end, the second masking unit 282 may include a gate circuit.

[0148] The second masking unit 282 outputs the crosstalk-free pulse 1220, and the processor 300 acquires information related to the object OBJ using the crosstalk-free pulse 1220. As a result, the LIDAR device 1000 of the present disclosure can acquire information related to the object OBJ more accurately.

[0149] FIG. 13 is a flow chart illustrating a method of operation of a LIDAR device according to one embodiment.

[0150] Referring to FIG. 13, the optical transmitter 100 may include a plurality of light sources and may irradiate light generated by the plurality of light sources toward a target object (S1310).

[0151] The optical transmitter 100 can scan the entire area of ​​the object OBJ through a plurality of light sources using a point scanning method in which point light is scanned onto the object OBJ. To this end, the optical transmitter 100 may include a beam steering element 180 that changes the aiming direction of the plurality of light sources so that the light generated by the plurality of light sources is aimed toward the object OBJ at different irradiation angles or the same irradiation angle.

[0152] The light receiving unit 200 can detect reflected light of the light irradiated toward the object OBJ via the multiple light detection elements 222 (S1320).

[0153] The light detection element 222 may include, but is not limited to, an avalanche photodiode (APD) or a single photon avalanche diode (SPAD) to increase the reception of reflected light.

[0154] Meanwhile, depending on the shape of the object OBJ, any one of the plurality of light detection elements 222 may receive a plurality of reflected lights, and any one of the plurality of reflected lights may correspond to crosstalk that causes an error in the position and shape analysis of the object OBJ.

[0155] In order to eliminate crosstalk, the LIDAR device 1000 according to the present disclosure can convert the detection information detected by the multiple optical detection elements 222 into a pulse signal with a pulse waveform.

[0156] When crosstalk occurs, a method in which the LIDAR device 1000 receives reflected light and converts the detection information into a pulse signal will be described with reference to FIG.

[0157] The optical receiving unit 200 can remove crosstalk from second detection information detected by at least one of the remaining optical detection elements based on first detection information detected by any one of the plurality of optical detection elements (S1330).

[0158] In this case, the second detection information means detection information output by the light detection element 222 that receives the plurality of reflected lights. Also, the first detection information is detection information used to remove crosstalk included in the second detection information, and is detection information different from the second detection information.

[0159] In one embodiment, the optical receiving unit 200 can determine whether the second detection information includes crosstalk based on at least one of the number of pulses included in the second detection information and the reception time points of the pulses. Furthermore, when the optical receiving unit 200 calculates that the second detection information includes crosstalk, the optical receiving unit 200 can identify the crosstalk in the second detection information. Furthermore, the optical receiving unit 200 can remove the identified crosstalk.

[0160] A method of calculating whether crosstalk is included or not and a method of identifying crosstalk will be described with reference to FIG. 15, and a method of removing crosstalk will be described with reference to FIG.

[0161] The processor 300 may obtain information related to the object OBJ using the detection information from which crosstalk has been removed (S1340).

[0162] The processor 300 may obtain information related to the object OBJ using the first detection information and the second detection information from which crosstalk has been removed.

[0163] The processor 300 can calculate the distance to the object OBJ based on the time of flight (ToF) of the light detected by the optical receiving unit 200, and perform data processing for analyzing the position and shape of the object OBJ.

[0164] FIG. 14 is a flow chart illustrating a method for detecting reflected light via a plurality of light detection elements.

[0165] Referring to FIG. 14, the optical receiving unit 200 can use the first optical detection element 222a to receive the first light irradiated from one of the plurality of light sources, the first light source 110a, toward the object OBJ via a first path (path 1) and output the first detection information (S1410).

[0166] In addition, the optical receiving unit 200 can use the second optical detection element 222b to receive a second light irradiated from a second light source 110b different from the first light source 110a toward the object OBJ via a second path (path 2) (S1420).

[0167] In this case, the first light detecting element 222a and the second light detecting element 222b are only for separating the light detecting elements that receive light, and do not mean the light detecting elements that are adjacent to each other.

[0168] On the other hand, when crosstalk occurs, the optical receiving unit 200 can use the second optical detection element 222b to receive the first light irradiated from the first light source 110a toward the object OBJ via a third path (path 3) different from the first path (path 1) and output second detection information (S1430).

[0169] In the second detection information output by the second light detection element 222b, information related to the first light may correspond to crosstalk.

[0170] The optical receiving unit 200 may convert the first detection information output by the first optical detection element 222a into a first pulse signal having a pulse waveform in order to remove crosstalk contained in the second detection information (S1440).

[0171] Furthermore, the optical receiving section 200 can convert the second detection information output by the second optical detection element 222b into a second pulse signal having a pulse waveform (S1450).

[0172] The first pulse signal is also transmitted to the crosstalk elimination unit 280 via the first channel (channel A). The second pulse signal is also transmitted to the crosstalk elimination unit 280 via the second channel (channel B).

[0173] The optical receiving unit 200 can allow the sharing of detection information between multiple channels. Thus, the first pulse signal is provided to the second channel (channel B), and the second pulse signal is also provided to the first channel (channel A). The shared pulse signal is also used for identifying and removing crosstalk.

[0174] The optical receiving section 200 can identify crosstalk in the second pulse signal based on the first pulse signal and remove the crosstalk from the second pulse signal.

[0175] FIG. 15 is a diagram for explaining a method for identifying crosstalk in detection information detected by a plurality of photodetection elements.

[0176] In one embodiment, steps S1510 to S1520 are performed before the detection information is converted into a pulse signal, and in another embodiment, steps S1510 to S1520 are performed after the detection information is converted into a pulse signal.

[0177] 15, the optical receiving unit 200 may determine whether or not crosstalk is included in the second detection information (S1510). In one embodiment, the optical receiving unit 200 may determine whether or not crosstalk is included in the second detection information based on at least one of the number of pulses included in the second detection information and the reception time points of the pulses.

[0178] For example, the optical receiving unit 200 may determine that the second detection information includes the crosstalk if the number of pulses included in the second detection information is two or more, but is not limited thereto.

[0179] When the optical receiving unit 200 calculates that the second detection information includes crosstalk, the optical receiving unit 200 can identify the crosstalk in the second detection information by using the first detection information.

[0180] The optical receiving unit 200 can identify crosstalk in the second detection information based on the pulse included in the first detection information. The optical receiving unit 200 can identify crosstalk in the second detection information based on at least one of a reception time point, a pulse width, and a pulse size of the pulse included in the first detection information.

[0181] In one embodiment, the optical receiving unit 200 may calculate a pulse having a pulse width wider than a preset pulse width among pulses included in the first detection information as a pulse due to the first light. Alternatively, the optical receiving unit 200 may calculate a pulse having a pulse size larger than a preset pulse size among pulses included in the first detection information as a pulse due to the first light. In this case, the preset pulse width and pulse size are set in consideration of the output of the optical transmitting unit 100.

[0182] In another embodiment, the optical receiving unit 200 may calculate a pulse having a maximum pulse width among the pulses included in the first detection information as a pulse due to the first light. Alternatively, the optical receiving unit 200 may calculate a pulse having a maximum pulse size among the pulses included in the first detection information as a pulse due to the first light.

[0183] The optical receiver 200 can identify the crosstalk included in the second detection information based on the pulse information by the first light included in the first detection information.

[0184] The optical receiver 200 can identify the crosstalk included in the second detection information based on the first reception time point of the first light included in the first detection information.

[0185] Depending on the shape of the object OBJ, the first reception time point of the first light detected by the first light detection element 222a may be longer or shorter than the second reception time point of the first light detected by the second light detection element 222b.

[0186] Therefore, the optical receiving unit 200 can determine that a pulse received between a time point preceding the first reception time point by a preset time point and a time point delayed by the preset time point is crosstalk.

[0187] The optical receiving unit 200 can remove the crosstalk identified in the second detection information (S1520).

[0188] FIG. 16 is a flowchart illustrating a method for removing crosstalk from detection information detected by a plurality of photodetection elements.

[0189] Referring to FIG. 16, the optical receiving unit 200 may calculate the earlier of the first reception point of the first light detected by the first optical detection element and the second reception point of the first light detected by the second optical detection element as the start point of crosstalk removal (S1610).

[0190] The optical receiving unit 200 can compare a first reception time point of the first light detected by the first optical detection element 222a with a second reception time point of the first light detected by the second optical detection element.

[0191] Depending on the shape of the object OBJ, the first reception time point of the first light detected by the first optical detection element 222a may be longer or shorter than the second reception time point of the first light detected by the second optical detection element 222b. Therefore, in order to completely remove crosstalk, the earlier of the first reception time point and the second reception time point must be set as the removal start time point of the crosstalk. For example, if the first reception time point is earlier than the second reception time point, the optical receiving unit 200 may determine the first reception time point as the removal start time point. Conversely, if the first reception time point is later than the second reception time point, the optical receiving unit 200 may determine the second reception time point as the removal start time point.

[0192] The optical receiving unit 200 can remove pulses that are located between the removal start point and the preset masking pulse width from the pulses included in the second pulse signal (S1620).

[0193] The optical receiver 200 outputs a masking pulse having a preset masking pulse width from the start of control, and can remove a pulse corresponding to crosstalk from the second pulse signal by using the masking pulse. For this purpose, the optical receiver 200 may include a gate circuit.

[0194] Meanwhile, the optical receiver 200 outputs a second pulse signal from which crosstalk has been removed, and the processor 300 can obtain information related to the object OBJ using the second pulse from which crosstalk has been removed.

[0195] As described above, even when the LIDAR device 1000 of the present disclosure includes multiple light sources and multiple light detection elements that receive light irradiated from the multiple light sources in order to realize high image resolution within a given frame time, it can eliminate crosstalk between the multiple light detection elements and more accurately analyze the position and shape of the object OBJ.

[0196] The above-described embodiments can be created into a program that can be executed by a computer, and can be realized by a general-purpose digital computer that runs the program using a computer-readable recording medium. The data structures used in the above-described embodiments can also be recorded on a computer-readable recording medium through various means. The computer-readable recording medium includes recording media such as magnetic recording media (e.g., ROM (read only memory), floppy disk, hard disk, etc.) and optically readable media (e.g., CD-ROM (compact disc read only memory), DVD (digital versatile disc), etc.).

[0197] Those skilled in the art in the art to which the present invention relates will understand that the present invention may be embodied in modified forms without departing from the essential characteristics of the present invention. Therefore, the disclosed embodiments should be considered from an explanatory perspective, not a limiting one. The scope of the invention is set forth in the claims, not in the above description, and all differences within the scope equivalent thereto should be interpreted as being included in the present invention. [Explanation of symbols]

[0198] 100 Optical transmitter 200 Optical receiver 300 processors 1000 Lidar Equipment

Claims

1. In the LIDAR device, A light transmitting unit including a plurality of light sources and configured to irradiate light generated by the plurality of light sources toward a target object; an optical receiver including a plurality of optical detection elements for detecting reflected light of light irradiated toward the target object, the optical receiver removing crosstalk from second detection information detected by at least one of the remaining optical detection elements based on first detection information detected by any one of the plurality of optical detection elements; a processor for acquiring information related to the object using the detection information from which the crosstalk has been removed; The optical receiving unit includes: a first light detection element that receives a first light irradiated from a first light source among the plurality of light sources toward the target object via a first path and outputs the first detection information related to the first light; a second light detection element that receives second light irradiated toward the target object from a second light source different from the first light source via a second path; a first detection signal converter that converts the first detection information output by the first light detection element into a first pulse signal having a pulse waveform; a second detection signal converter that converts the second detection information output by the second light detection element into a second pulse signal having a pulse waveform; a crosstalk removal unit that determines an earlier one of a first reception time point of the first light detected by the first light detection element and a second reception time point of the first light detected by the second light detection element as a removal start time point of the crosstalk, and removes pulses that are located between the removal start time point and a preset masking pulse width from among pulses included in the second pulse signal, The crosstalk may be The first light emitted from the first light source toward the target object is further received by the second light detection element via a third path different from the first path, The second light detection element is A LIDAR device that outputs the second detection information related to the first light and the second light when the crosstalk occurs.

2. The masking pulse width is The LIDAR device according to claim 1 , wherein the pulse width is set wider than the pulse width of the first light irradiated by the optical transmitter.

3. The optical transmitter unit includes: The lidar device of claim 1 or 2, further comprising a beam steering element that adjusts a direction of light generated by the multiple light sources so as to scan the target object.

4. The LIDAR device of claim 3 , wherein the beam steering element adjusts the aiming direction of the light by mechanical rotation.

5. The optical receiving unit includes: The LIDAR device according to claim 1 , further comprising a plurality of counters each counting the flight time of light detected by each of the plurality of light detection elements.

6. The processor, A LIDAR device according to any one of claims 1 to 5, which calculates a distance to the target object based on the flight time of the light detected by the optical receiving unit, and processes data for analyzing the position and shape of the target object.

7. 1. A method of operating a LIDAR device, comprising: Irradiating light generated by a plurality of light sources toward a target object; detecting reflected light of the light irradiated toward the target via a plurality of light detection elements; removing crosstalk from second detection information detected by at least one of the remaining photodetection elements based on first detection information detected by any one of the plurality of photodetection elements; and acquiring information related to the object using the detection information from which the crosstalk has been removed; The detecting step includes: receiving a first light irradiated toward the target from a first light source of the plurality of light sources via a first path using a first light detection element, and outputting the first detection information related to the first light; receiving, via a second path, a second light emitted from a second light source different from the first light source toward the object using a second light detection element; converting the first detection information output by the first light detection element into a first pulse signal having a pulse waveform; and converting the second detection information output by the second optical detection element into a second pulse signal having a pulse waveform. The removing step includes: determining an earlier one of a first reception time point of the first light detected by the first light detection element and a second reception time point of the first light detected by the second light detection element as a crosstalk removal start time point; removing pulses located between the removal start time and a preset masking pulse width from the pulses included in the second pulse signal; The crosstalk may be When crosstalk occurs because the first light irradiated from the first light source toward the target object is further received by the second light detecting element via a third path different from the first path, the method further includes a step of outputting the second detection information related to the first light and the second light using the second light detecting element.

8. The masking pulse width is The method according to claim 7 , wherein the pulse width of the first light and the pulse width of the second light are set wider than each other.

9. The obtaining step includes:

9. The method of claim 7 or 8, comprising counting the time of flight of light detected at each of the plurality of light detection elements.

10. The obtaining step includes: The method according to claim 9 , further comprising the step of calculating a distance to the object based on the flight time, and performing data processing for analyzing the position and shape of the object.

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