LiDAR equipment and methods for operating LiDAR equipment

Abstract

A LiDAR (Light Detection and Ranging) device is provided, comprising: a light emitter including a plurality of light sources, each of the plurality of light sources being configured to emit light toward an object; a light receiver including a plurality of light detection elements, each of the plurality of light detection elements being configured to detect reflected light reflected from an object illuminated by light emitted by the plurality of light sources, and the light receiver being configured to eliminate crosstalk from second detection information output by at least one of the plurality of light detection elements based on first detection information output by any one of the plurality of light detection elements; and a processor configured to obtain information about the object based on the second detection information with crosstalk eliminated.

Description

[0001] Cross-references to related applications

[0002] This application claims priority to Korean Patent Application No. 10-2020-0002144, filed on January 7, 2020, with the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0003] The exemplary embodiments disclosed herein relate to LiDAR devices and methods of operation thereof. Background Technology

[0004] Light detection and ranging (LiDAR) systems are used in a variety of fields, such as aerospace, geology, 3D mapping, automotive, robotics, and drones.

[0005] LiDAR devices use the time-of-flight (ToF) of light as their basic operating principle. For example, a LiDAR device can emit light towards an object, receive the light through a sensor, and use high-speed circuitry to measure the ToF. Furthermore, a LiDAR device can use the ToF to calculate the distance to the object and generate a depth image of the object by using the distance calculated for each location on the object.

[0006] Furthermore, to achieve high image resolution within a given frame time, LiDAR devices can include multiple light sources and multiple photodetectors for receiving light emitted from these sources. However, in this case, errors in Time-of-Flight (ToF) calculations may occur when one photodetector receives light emitted from two sources.

[0007] Therefore, a technique is needed to distinguish the received signal from the detection information output by the photodetector and to eliminate crosstalk. Summary of the Invention

[0008] One or more example embodiments provide a LiDAR device and a method of operating thereof capable of eliminating crosstalk.

[0009] Additional aspects will be set forth in part in the following description, and will become clear in part from the description, or may be learned by practicing the embodiments presented in this disclosure.

[0010] According to one aspect of an example embodiment, a light detection and ranging (LiDAR) device is provided, comprising: a light emitter including a plurality of light sources, each of the plurality of light sources being configured to emit light toward an object; a light receiver including a plurality of light detection elements, each of the plurality of light detection elements being configured to detect reflected light reflected from the object illuminated by the light emitted by the plurality of light sources, and the light receiver being configured to eliminate crosstalk from second detection information output by at least one of the plurality of light detection elements based on first detection information output by any one of the plurality of light detection elements; and a processor configured to obtain information about the object based on the second detection information with crosstalk eliminated.

[0011] The light receiver may include: a first light detection element configured to receive, via a first path, first reflected light reflected from the object illuminated by a first light emitted by a first light source among the plurality of light sources, and output first detection information corresponding to the first reflected light; and a second light detection element configured to receive, via a second path, second reflected light reflected from the object illuminated by a second light emitted by a second light source among the plurality of light sources, the second light source being different from the first light source, wherein the crosstalk is generated based on the second light detection element also receiving the first reflected light via a third path different from the first path, and wherein, based on the generated crosstalk, the second light detection element outputs second detection information corresponding to the first reflected light and the second reflected light.

[0012] The optical receiver may further include: a first detection signal converter configured to convert the first detection information output by the first optical detection element into a first pulse signal; and a second detection signal converter configured to convert the second detection information output by the second optical detection element into a second pulse signal.

[0013] The optical receiver may be configured to determine the earlier of a first reception time point of the first reflected light detected by the first optical detection element and a second reception time point of the first reflected light detected by the second optical detection element as the crosstalk cancellation start time point, and the optical receiver may further include a crosstalk cancellation element configured to cancel pulses located within a predetermined masking pulse width starting from the cancellation start time point from the pulses included in the second pulse signal.

[0014] The predetermined masking pulse width can be set to be greater than the pulse width of the first reflected light.

[0015] The light emitter may further include a beam steering element configured to adjust the emission direction of light emitted by each of the plurality of light sources to scan the object.

[0016] The beam steering element can be configured to control the emission direction of light emitted by each of the plurality of light sources by mechanical rotation.

[0017] The optical receiver may include a plurality of counters configured to count the time of flight of light detected by each of the plurality of optical detection elements.

[0018] The processor can also be configured to: obtain the distance to the object based on the time of flight of the light detected by each of the plurality of photodetectors, and analyze the position and shape of the object.

[0019] According to another aspect of an example embodiment, a method for operating a light detection and ranging (LiDAR) device is provided, the method comprising: emitting light from a plurality of light sources toward an object; detecting reflected light reflected from the object illuminated by the light emitted from the plurality of light sources by a plurality of light detection elements; eliminating crosstalk from second detection information output by at least one of the plurality of light detection elements based on first detection information output by any one of the plurality of light detection elements; and obtaining information about the object based on the second detection information with crosstalk eliminated.

[0020] The detection of reflected light may include: receiving, via a first optical detection element, first reflected light reflected from the object illuminated by a first light emitted from a first light source among the plurality of light sources through a first path, and outputting first detection information corresponding to the first reflected light by the first optical detection element; and receiving, via a second optical detection element, second reflected light reflected from the object illuminated by a second light emitted from a second light source among the plurality of light sources through a second path, the second light source being different from the first light source, wherein the crosstalk may be generated based on the second optical detection element also receiving the first reflected light via a third path different from the first path, and wherein the method may further include: based on the generation of the crosstalk, outputting second detection information corresponding to the first reflected light and the second reflected light by the second optical detection element.

[0021] The detection of reflected light may further include: converting the first detection information output by the first optical detection element into a first pulse signal; and converting the second detection information output by the second optical detection element into a second pulse signal.

[0022] The crosstalk elimination may include: determining the earlier of a first reception time point of the first reflected light detected by the first optical detection element and a second reception time point of the first reflected light detected by the second optical detection element as the crosstalk elimination start time point; and eliminating pulses located within a predetermined masking pulse width starting from the elimination start time point from the pulses included in the second pulse signal.

[0023] The predetermined masking pulse width can be set to be greater than the pulse width of the first reflected light and the pulse width of the second reflected light, respectively.

[0024] The information obtained may include counting the flight time of light detected by each of the plurality of photodetectors.

[0025] The information obtained may further include: obtaining the distance to the object based on the time of flight, and analyzing the position and shape of the object.

[0026] The method may further include: adjusting the emission direction of light generated by each of the plurality of light sources to scan the object.

[0027] The emission direction of light emitted by the multiple light sources can be adjusted based on mechanical rotation.

[0028] According to another aspect of an example embodiment, a light detection and ranging (LiDAR) device is provided, comprising: a light emitting device including a first light source configured to emit a first light toward an object and a second light source configured to emit a second light toward the object; a light receiving device including: a first light detection element configured to detect first reflected light reflected from the object illuminated by the first light via a first path and output first detection information corresponding to the first reflected light; a second light detection element configured to detect at least a second reflected light reflected from the object illuminated by the second light via a second path and output second detection information corresponding to the at least second reflected light; a first detection signal converter configured to convert the first detection information output by the first light detection element into a first pulse signal; and a second detection signal converter configured to convert the second detection information output by the second light detection element into a second pulse signal; and a processor configured to obtain information about the object based on the second detection information with crosstalk eliminated, wherein the crosstalk is generated based on the second light detection element also receiving the first reflected light reflected from the object illuminated by the first light via a third path different from the first path.

[0029] The optical receiver can be configured to determine the earlier of a first reception time point of the first reflected light detected by the first optical detection element and a second reception time point of the first reflected light detected by the second optical detection element as the crosstalk cancellation start time point, and wherein the optical receiver may further include a crosstalk cancellation element configured to cancel pulses located within a predetermined masking pulse width starting from the cancellation start time point from the pulses included in the second pulse signal. Attached Figure Description

[0030] The above and / or other aspects, features, and advantages of particular exemplary embodiments will become clearer from the following description taken in conjunction with the accompanying drawings, in which:

[0031] Figure 1 This illustrates the configuration of a LiDAR device according to an example embodiment;

[0032] Figure 2 An exemplary arrangement and operation of the light emitter and light receiver of a LiDAR device according to an example embodiment are shown;

[0033] Figure 3A and Figure 3B An example of a beam steering element and point scanning principle set in a LiDAR device according to an exemplary embodiment is shown;

[0034] Figure 4 An exemplary configuration of the processor included in a LiDAR device according to an example embodiment is shown;

[0035] Figure 5 Showing through Figure 4 An example of a processor dividing a target region;

[0036] Figure 6 An exemplary circuit configuration of a light receiver included in a LiDAR device according to an example embodiment is shown;

[0037] Figure 7A and Figure 7B This shows the detection information output by the optical receiver when no crosstalk occurs;

[0038] Figure 8A and Figure 8B This shows the detection information output by the optical receiver when crosstalk occurs;

[0039] Figure 9 An internal block diagram of a light receiver included in a LiDAR device according to an example embodiment is shown;

[0040] Figure 10A and Figure 10B Showing the use Figure 9A method for identifying and eliminating crosstalk between the first and second detection information;

[0041] Figure 11 An example is shown in the case of crosstalk;

[0042] Figure 12 An example is shown in the case of eliminating crosstalk by masking pulses;

[0043] Figure 13 This is a flowchart illustrating a method of operating a LiDAR device according to an example embodiment;

[0044] Figure 14 This is a flowchart illustrating a method for detecting reflected light using multiple photodetectors;

[0045] Figure 15 This is a flowchart illustrating a method for identifying crosstalk in detection information output by multiple optical detection elements; and

[0046] Figure 16 This is a flowchart illustrating a method for eliminating crosstalk in detection information output by multiple optical detection elements. Detailed Implementation

[0047] Reference will now be made in detail to the exemplary embodiments shown in the accompanying drawings, wherein similar reference numerals denote similar elements throughout the drawings. In this respect, the exemplary embodiments may take different forms and should not be construed as limited to the description set forth herein.

[0048] Therefore, exemplary embodiments are described below only with reference to these accompanying drawings to illustrate these aspects. As used herein, the term "and / or" includes any item in the relevant list and all combinations of one or more items. When a statement such as "at least one" follows a list of elements, it modifies the entire list of elements without modifying any individual element of the list. For example, the statement "at least one of a, b, and c" should be understood to include only a, only b, only c, both a and b, both a and c, both b and c, or all of a, b, and c.

[0049] The phrases “in some exemplary embodiments” or “in exemplary embodiments” that appear in various places in the specification do not necessarily all refer to the same exemplary embodiment.

[0050] Some example embodiments can be represented by functional block configurations and various processing steps. Some or all of these functional blocks can be implemented in various numbers of hardware and / or software configurations to perform a particular function. For example, a functional block according to an example embodiment can be implemented by one or more microprocessors or by a circuit configuration for a given function. Furthermore, for example, a functional block according to an example embodiment can be implemented by various programming languages ​​or scripting languages. The functional block can be implemented as an algorithm that executes on one or more processors. In addition, this disclosure can employ related techniques for electronic configuration, signal processing, and / or data processing. Terms such as “mechanism,” “element,” “device,” and “configuration” can be used broadly and are not limited to mechanical and physical configurations.

[0051] Furthermore, the connecting lines or connecting components shown in the accompanying drawings are merely examples of functional and / or physical or circuit connections. In actual devices, connections between components can be represented by various functional, physical, or circuit connections that can be replaced or added.

[0052] Figure 1 This is a block diagram illustrating the configuration of a LiDAR device according to an example embodiment.

[0053] Reference Figure 1 The LiDAR device 1000 may include: a light emitter 100 that emits and scans light onto an object OBJ; a light receiver (light receiving device) 200 that detects light reflected from the object OBJ illuminated by light emitted from the light emitter (light receiving device) 100; and a processor 300 that controls the light receiver 200. It will be apparent to those skilled in the art that, in addition to... Figure 1 In addition to the components shown, the LiDAR device 1000 may also include other common components.

[0054] The light emitter 100 may include: a light source assembly 110, which includes multiple light sources (light source 1, light source 2, ..., light source N); and a beam steering element 180.

[0055] In an example embodiment, the arrangement and driving of the light source assembly 110 and the beam steering element 180 can be defined such that light from each of the plurality of light sources scans the object OBJ at a different emission angle through the beam steering element 180. In another example embodiment, the arrangement and driving of the light source assembly 110 and the beam steering element 180 can be defined such that light from each of the plurality of light sources scans the object OBJ at the same emission angle through the beam steering element 180.

[0056] The light source assembly 110 can emit light for analyzing the position and shape of the object OBJ. The light source assembly 110 generates and emits light with a predetermined wavelength, and emits light in a band suitable for analyzing the position and shape of the object OBJ, such as infrared light. Using infrared light prevents it from mixing with natural light in the visible light region, including sunlight. However, embodiments are not limited to the infrared band, and the light source assembly 110 can emit light in various bands.

[0057] The light source assembly 110 may include light sources such as laser diodes (LDs), edge-emitting lasers, vertical-cavity surface-emitting lasers (VCSELs), distributed feedback lasers, light-emitting diodes (LEDs), and superluminescent diodes (SLDs). The light source assembly 110 can generate and emit light in multiple different wavelength bands. The light source assembly 110 can generate and emit pulsed or continuous light.

[0058] The light source of the light source assembly 110 can emit light toward the object OBJ under the control of the processor 300. For example, the processor 300 can set the emission direction or emission angle of the light from each light source and control the light source assembly 110 so that the multiple light sources emit light according to the set emission angle or direction.

[0059] The beam steering element 180 directs the light emitted from the light source assembly 110 toward the object OBJ, and sequentially adjusts the steering direction so that the point light emitted from the light source assembly 110 scans the entire object OBJ. A scanning mirror or an optical phased array can be used as the beam steering element 180.

[0060] The light receiver 200 classifies the reflected light from the object OBJ according to the position of the reflected light, such that the light receiver 200 may include multiple pixelated regions capable of detecting light.

[0061] like Figure 1 As shown, the light receiver 200 may include a detector array 220 divided into a plurality of pixels PX1, PX2, ..., PXm. A light detection element 222 may be disposed in each of the plurality of pixels PX1, PX2, ..., PXm. For example, the light detection element 222 forms pixels PX1, PX2, ..., PXm classified according to their position in the detector array 220, and each of the pixels PX1, PX2, ..., PXm can detect reflected light from the object OBJ separately from the light emitted from the light source assembly 110.

[0062] The light receiver 200 may include a circuit unit 240 that can measure the ToF of each light detected at each of the plurality of light detection elements 222, and the light receiver 200 may also include optical elements for collecting light from the object OBJ into a predetermined pixel.

[0063] The plurality of light-detecting elements 222 may be sensors capable of sensing light, and may be light-receiving elements that generate electrical signals based, for example, on the energy of the sensed light. There are no specific limitations on the type of light-receiving elements.

[0064] The LiDAR device 1000 according to the example embodiment uses the point scanning method described above; therefore, the intensity of the light received by the light detection element 222 can be lower than in other schemes, such as flash schemes. Therefore, the light detection element 222 can be an avalanche photodiode (APD) or a single-photon avalanche diode (SPAD) with high sensing sensitivity. The specific circuit configuration of the analog front-end (AFE), time-to-digital converter (TDC), etc., can vary depending on which light detection element 222 of the light receiver 200 includes an APD or a SPAD.

[0065] The processor 300 can use the light detected by the light receiver 200 to perform signal processing to obtain information about the object OBJ. For example, the processor 300 can determine the distance to each location of the object OBJ based on the Time-of-Flight (ToF) of the light reflected from the object OBJ, and perform data processing to analyze the position and shape of the object OBJ.

[0066] The information analyzed by processor 300, namely, information about the shape and position of object OBJ, can be sent to another component or device and used. For example, such information can be sent to the controller of an autonomous driving device, such as an unmanned vehicle or drone, that incorporates LiDAR device 1000. Additionally, such information can be used in smartphones, mobile phones, personal digital assistants, laptops, personal computers (PCs), various wearable devices, and other mobile or non-mobile computing devices.

[0067] The processor 300 can also control the overall operation of the LiDAR device 1000, including the control of the light emitter 100 and the light receiver 200. The processor 300 can divide the area of ​​the object OBJ by taking into account the number of light sources included in the light source assembly 110, generate control signals for the beam steering element 180 to scan all the divided areas, and apply the control signals to the beam steering element 180.

[0068] Furthermore, the processor 300 can control the operation of the light source assembly 110 and the light receiver 200. For example, the processor 300 can perform power control, on / off control, and pulsed wave (PW) or continuous wave (CW) generation control on the light source assembly 110. Additionally, the processor 300 can apply control signals to each of the photodetector elements 222 in the light receiver 200.

[0069] In an example embodiment, the processor 300 can group the light detection elements 222 into multiple groups, and the light receiver 200 can classify and detect the light emitted from the light source assembly 110 for each group.

[0070] The processor 300 can set the number of light detection elements 222 included in each group based on the surrounding environment. For example, when the ambient illuminance of the light receiver 200 is a first illuminance, the processor 300 can group each group to include a first number of light detection elements 222, and when the ambient illuminance of the light receiver 200 is a second illuminance less than the first illuminance, the processor 300 can group each group to include a second number of light detection elements 222, wherein the second number is greater than the first number. The light detection elements 222 can be overlapped and output a detection signal for each group, and the processor 300 can classify and detect the light emitted from the light source assembly 110 for each group.

[0071] The LiDAR device 1000 may also include a memory in which programs and other data for operations performed by the processor 300 are stored.

[0072] The memory is hardware that stores various types of data processed by the LiDAR device 1000. For example, the memory can store data already processed by the LiDAR device 1000 and data to be processed. In addition, the memory can store applications, drivers, etc., that will be driven by the LiDAR device 1000.

[0073] The memory includes random access memory (RAM) such as dynamic random access memory (DRAM), static random access memory (SRAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), CD-ROM, Blu-ray disc or other optical disc storage, hard disk drive (HDD), solid-state drive (SSD) or flash memory, and in addition, the memory may include other external storage devices that can be accessed by the LiDAR device 1000.

[0074] Figure 2 An exemplary arrangement and operation of the light emitter and light receiver of a LiDAR device according to an example embodiment are shown.

[0075] Reference Figure 2According to the example embodiment, the LiDAR device 1000 employs a light emitter 100 that uses a point scanning method to scan point light onto an object OBJ, enabling the LiDAR device 1000 to scan the entire area of ​​the object OBJ using multiple light sources.

[0076] For example, such as Figure 2 As shown, the first light source 110a and the second light source 110b emit light toward the beam steering element 180 at different angles, and have an angle θ between the two radiation lines L1 and L2 directed by the beam steering element 180. Angle θ is sufficient to be an angle of light detectable by distinguishing reflected light from the object OBJ among the different pixels included in the detector array 220. This angle can be determined based on the resolution of the detector array 220 constituting the light receiver 200 and the performance of the additional optical elements included in the light receiver 200. For example, the angle θ can be approximately 1° or greater.

[0077] The time T1 for light radiated from the first light source 110a and the time T2 for light radiated from the second light source 110b can be the same; however, the embodiments are not limited to this, and T1 and T2 can be different. The time difference between T1 and T2 can be, for example, within 1 μs.

[0078] Each of the radiation lines L1 and L2 is oriented according to the drive of the beam steering element 180 and scans the entire field of view (FOV) including the object. Light from the object can be directed to different pixels of the detector array 220, and as shown, a lens 280 can also be configured to focus the light onto the pixels of the detector array 220.

[0079] Each pixel of the detector array 220 is connected to a circuit element for ToF calculation, and the values ​​of the first ToF "ToF#1" and the second ToF "ToF#2" can be obtained through predetermined calculations.

[0080] The LiDAR device 1000 according to the example embodiment uses a point scanning method for scanning point light onto an object OBJ via a light emitter 100, and has a resolution limitation due to the speed of light. For example, within a given frame time, i.e., within a given reference time for forming a frame image of the object OBJ, the amount of information (e.g., point cloud) that can be obtained for the object OBJ is limited. This limits the image resolution. Therefore, in order to increase the FOV while maintaining spatial resolution, the frame time is increased, and this performance degradation increases with increasing distance from the object OBJ.

[0081] The LiDAR device 1000 according to the example embodiment can use multiple light sources to improve the resolution limitation. Furthermore, in the example embodiment, the multiple light sources can maintain different emission angles. Therefore, the image resolution can be increased proportionally to the number of light sources included in the LiDAR device 1000.

[0082] Figure 3A and Figure 3B An example of a beam steering element and point scanning principle is shown in a LiDAR device according to an example embodiment.

[0083] Reference Figure 3A The scanning mirror SM is mechanically rotated and the orientation of the reflective surface is adjusted to adjust the incident light L. i The direction of rotation. Based on the rotation angle, the incident light L... i The direction of the turn is sequentially adjusted to L. S1 L S2 and L S3 The rotation of the scanning mirror SM is shown as a single-axis rotation, but is not limited to this. For example, the rotation of the scanning mirror SM can be a dual-axis rotation, wherein the scanning mirror SM is driven to rotate relative to two rotation axes.

[0084] The scanning mirror SM is also shown to have a reflective surface, but the embodiment is not limited to this. For example, multiple reflective mirror elements can be arranged and their respective orientations can be adjusted to allow the incident light L to... i Turn in the direction of object OBJ.

[0085] Reference Figure 3B An optical phased array (OPA) can include multiple channels CH1, CH2, ... A phase transition value can be set to change the phase of the incident light in each of the multiple channels CH1, CH2, ... and therefore, the phase of the incident light L can be adjusted. i The direction in which it is turned and launched.

[0086] Each of the multiple channels CH1, CH2, ... of an optical phased array (OPA) may include a meta-element with a subwavelength shape and size, whose phase transition value relative to the incident light can be electrically adjusted.

[0087] Optical phased arrays (OPAs) can be based on silicon photonics optical waveguides, which can conduct incident light L... i The optical waveguide is divided into multiple paths, and these multiple paths are directed to various output terminals (e.g., multiple channels). Such an optical waveguide may include a phase retarder disposed in each of the multiple branch paths, and the length of each path and / or the degree of phase delay in the phase retarder of each path can be adjusted to adjust the incident light L. i The direction in which it is turned and launched.

[0088] Optical phased array (OPA) redirects light to the direction of incidence L in each channel. i The direction is determined by the combination of phase transitions that occur. Based on the combination of phase transition values, the incident light L... i The direction of turning and launching is sequentially adjusted to L. S1 L S2 and L S3 .

[0089] Figure 4 A block diagram illustrating an exemplary configuration of the processor included in a LiDAR device according to an example embodiment is shown, and Figure 5 Showing through Figure 4 An example of how a processor divides a target region.

[0090] Reference Figure 4 and Figure 5 The processor 300 may include a target region divider 330 and an analyzer 350. The code for executing the target region divider 330 and the analyzer 350 may be stored in a memory provided in the LiDAR device 1000, and the code may be executed by the processor 300.

[0091] The target area divider 330 can divide a predetermined FOV range including the object OBJ into the same number of light sources included in the LiDAR device 1000. Figure 5 This example illustrates dividing the FOV range into six segments when the number of light sources is six. However, this is merely an example, and the number or form of division is not limited to this.

[0092] The target region divider 330 can generate a scanning control signal that causes the divided region to be scanned by the light emitter 100, and apply the scanning control signal to the light emitter 100. For example, when the beam steering element 180 is as follows: Figure 3A When the scanning mirror SM is shown, the scanning control signal can be a rotation drive control signal used to control the rotation direction and rotation angle of the scanning mirror SM.

[0093] When the beam steering element 180 is as follows Figure 3B When performing an optical phased array (OPA) as shown, the scan control signal can be a phase control signal to be applied to each channel. The phase control signal can be an electrical signal to be applied to the super-element constituting each channel, or it can be a phase delay signal used to set a phase delay unit in each channel.

[0094] The analyzer 350 can analyze the position and shape of the object OBJ by taking into account the emission angle of the light emitted onto the object OBJ and the ToF value calculated based on the emission angle.

[0095] Figure 6 An exemplary circuit configuration of a light receiver included in a LiDAR device according to an example embodiment is shown.

[0096] Reference Figure 6 The optical receiver 200 may include a plurality of optical detection elements 222, a crosstalk cancellation element 247 for eliminating crosstalk from the light detected by each of the plurality of optical detection elements 222, and a plurality of time counters 249 for measuring the ToF of the crosstalk-free light.

[0097] The optical receiver 200 may include: a plurality of current-to-voltage conversion circuits 241 for converting the current output from each of the plurality of optical detection elements 222 into a voltage; a plurality of amplifiers 243 for amplifying the voltage converted by each of the plurality of current-to-voltage conversion circuits 241; and a plurality of peak detectors 245 for detecting peak values ​​in the signal amplified by the plurality of amplifiers 243.

[0098] Multiple optical detection elements 222 can detect light L1, light L2, and light L3 received from the object OBJ and output detection information. The detection information output by the multiple optical detection elements 222 can be sent to the processor 300 through multiple channels ch1, ch2, and ch3.

[0099] Specifically, multiple optical detection elements 222 can detect light L1, light L2 and light L3 from the object OBJ respectively, and output current signals.

[0100] Multiple current-to-voltage conversion circuits 241 can convert the current signal output from each of the multiple photodetectors 222 into a voltage signal.

[0101] Multiple amplifiers 243 can amplify the voltage signal output by each of the multiple current-to-voltage conversion circuits 241.

[0102] Multiple peak detectors 245 can detect peak values ​​in a voltage signal amplified by each of the multiple amplifiers 243. For example, the multiple peak detectors 245 can detect peak values ​​by detecting the rising and falling edges of the electrical signal. Alternatively, the multiple peak detectors 245 can use a constant ratio discriminator (CFD) method to detect peak values. The multiple peak detectors 245 may also include a comparator and can convert the detected peak values ​​into pulse signals and output the pulse signals.

[0103] Furthermore, since the detection information output by the photodetector 222 represents information related to the light received by the photodetector 222, the detection information described below can represent at least one of the current signal output by the photodetector 222, the voltage signal converted by the current-to-voltage conversion circuit 241, the voltage signal amplified by the amplifier 243, and the pulse signal output by the comparator.

[0104] Multiple crosstalk cancellation elements 247 can eliminate crosstalk from the individual detection information output by multiple optical detection elements 222. (Refer to the following...) Figure 9 The crosstalk cancellation method of the crosstalk cancellation element 247 is described in more detail.

[0105] Multiple time counters 249 can use crosstalk-eliminated detection information to measure the Time-of-Flight (ToF) of light. When a pulse signal output from each of the multiple peak detectors 245 is input to each of the multiple time counters 249, each of the multiple time counters 249 can count the number of cycles of the clock signal generated by the light source from the point of light radiation, and measure the ToF of the light. Additionally, each of the multiple time counters 249 can store information about each ToF of the measured light in a register. Each of the multiple time counters 249 may include a Time-Diverter Control (TDC).

[0106] Measurement results measured by multiple time counters 249 are sent to processor 300, and processor 300 can use the measurement results to perform data processing to analyze information about the object, such as the object's position and shape.

[0107] Figure 7A and Figure 7B This shows the detection information output by the optical receiver when no crosstalk occurs.

[0108] Reference Figure 7A and Figure 7B The first light source 110a and the second light source 110b can generate a first light L1 and a second light L2, respectively. The first light source 110a and the second light source 110b can emit the first light L1 and the second light L2 toward the object OBJ to analyze the position and shape of the object OBJ.

[0109] In an example embodiment, the LiDAR device 1000 may further include a beam steering element 180 for adjusting the aiming direction of the first light source 110a and the second light source 110b, and the beam steering element 180 may allow the point light output from the first light source 110a and the point light output from the second light source 110b to scan the entire object OBJ.

[0110] The first light L1 generated by the first light source 110a and emitted toward the object OBJ can be sent to the first light detection element 222a through the first path "path 1". The second light L2 generated by the second light source 110b and emitted toward the object OBJ can be sent to the second light detection element 222b through the second path "path 2".

[0111] 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 can be combined with... Figure 7B The detection information is the same.

[0112] The optical receiver 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. Additionally, the optical receiver 200 can calculate the Time-of-Flight (ToF#2) of the second light 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#2) of the second light L2.

[0113] like Figure 7A and Figure 7B As shown, when there is no crosstalk between the optical detection elements, since each optical detection element receives only one beam of light, the LiDAR device 1000 can analyze the position and shape of the object OBJ even if the Time-of-Flight (ToF) of the light is calculated based on the detection information output by each optical detection element. However, if crosstalk occurs between the optical detection elements, significant errors will occur in the position and shape analysis of the object OBJ when the Time-of-Flight of the light is calculated based on the detection information output by each optical detection element.

[0114] Figure 8A and Figure 8B It is a diagram used to describe the detection information output by the optical receiver when crosstalk occurs.

[0115] Reference Figure 8A and Figure 8B ,like Figure 7A and Figure 7B As shown, the first light detection element 222a can receive the first light L1 emitted from the first light source 110a toward the object OBJ through the first path "path 1", and the second light detection element 222b can receive the second light L2 emitted from the second light source 110b toward the object OBJ through the second path "path 2".

[0116] Furthermore, depending on the shape of the object OBJ, the second optical detection element 222b may receive the first light L1 emitted from the first light source 110a toward the object OBJ via a third path "path 3" different from the first path "path 1". Because the second optical detection element 222b receives the first light L1 in addition to receiving the desired second light L2, the first light L1 can correspond to the crosstalk in the detection information output by the second optical detection element 222b.

[0117] Figure 8B This is a diagram showing the detection information 810 detected by the first optical detection element 222a and the detection information 820 detected by the second optical detection element 222b.

[0118] exist Figure 8B As can be seen, the detection information 820 detected by the second optical detection element 222b includes pulse signals similar to the pulse signals detected by the first optical detection element 222a. The pulse signals in the detection information 820 detected by the second optical detection element 222b that are similar to the pulse signals detected by the first optical detection element 222a may be crosstalk.

[0119] Because the crosstalk detected by the second photodetector 222b is generated by the first light L1 produced by the first light source 110a, the processor 300 may be unable to accurately analyze the position and shape of the object OBJ when the second photodetector 222b misidentifies the first light L1 as the second light L2 and outputs detection information. A method for eliminating crosstalk from the detection information output by the photodetectors 222a and 222b will be described below.

[0120] In addition, Figure 8A and Figure 8B The example only shows crosstalk between the first light detection element 222a and the second light detection element 222b generated by the first light source 110a and the second light source 110b, but the embodiment is not limited to this. According to the example embodiment, the number of light sources can be increased, and the number of light detection elements that cause crosstalk can be increased.

[0121] Figure 9 An internal block diagram of a light receiver included in a LiDAR device according to an example embodiment is shown.

[0122] Reference Figure 9 The optical receiver 200 may include a detector array 220 in which a plurality of optical detection elements 222 are disposed, a signal converter 260 for converting the light detected by the plurality of optical detection elements 222 into a detection signal for ToF calculation, and a crosstalk cancellation element 280 for eliminating crosstalk from the detection signal output from the signal converter 260.

[0123] Multiple light detection elements 222 can be arranged in the detector array 220 to receive reflected light emitted by the light emitter 100 toward the object OBJ.

[0124] In an example embodiment, the plurality of light detection elements 222 may be a first light detection element 222a and a second light detection element 222b.

[0125] The first light detection element 222a can receive the first light L1 emitted from the first light source 110a toward the object OBJ via a first path "path 1", and the second light detection element 222b can receive the second light L2 emitted from the second light source 110b (different from the first light source 110a) toward the object OBJ via a second path "path 2". Furthermore, if the second light detection element 222b also receives the first light L1 emitted from the first light source 110a toward the object OBJ via a third path "path 3" (different from the first path "path 1"), crosstalk may occur.

[0126] The first optical detection element 222a can output first detection information about the first light L1. Additionally, the second optical detection element 222b can output second detection information about the first light L1 and the second light L2.

[0127] The first detection information output by the first optical detection element 222a and the second detection information output by the second optical detection element 222b can be sent to the processor 300 through the first channel "Channel A" and the second channel "Channel B" respectively.

[0128] Specifically, when the first light L1 is received, the first photodetector 222a can output a first current signal 910 corresponding to the first light L1. When the first light L1 and the second light L2 are received, the second photodetector 222b can output a second current signal 920 corresponding to the first light L1 and the second light L2. The second current signal 920 output by the second photodetector 222b may include crosstalk caused by the first light L1.

[0129] The first current signal 910 can be input to the signal converter 260 as first detection information. Additionally, the second current signal 920 can be input to the signal converter 260 as second detection information.

[0130] Signal converter 260 can convert the current signal output by multiple photodetectors 222 into a pulse signal for ToF calculation. Signal converter 260 can be configured to include... Figure 6 The entirety of the current-to-voltage conversion circuit 241, amplifier 243, peak detector 245, and comparator.

[0131] Signal converter 260 may include multiple detection signal converters respectively connected to multiple photodetector elements 222 to convert current signals into pulse signals. In an example embodiment, signal converter 260 may include a first detection signal converter 261 connected to a first photodetector element 222a and a second detection signal converter 262 connected to a second photodetector element 222b.

[0132] The first detection signal converter 261 converts the first current signal 910 output from the first photodetector 222a into a first voltage signal and amplifies the first voltage signal. Additionally, the first detection signal converter 261 detects peak values ​​in the amplified first voltage signal, converts the detected peak values ​​into a first pulse signal 930, and outputs the first pulse signal 930. Similarly, the second detection signal converter 262 converts the second current signal 920 output from the second photodetector 222b into a second voltage signal and amplifies the second voltage signal. It then detects peak values ​​in the amplified second voltage signal, converts the peak values ​​into a second pulse signal 940, and outputs the second pulse signal 940. The second pulse signal 940 output by the second detection signal converter 262 may still include crosstalk caused by the first light L1.

[0133] The first pulse signal 930 can be input to the crosstalk cancellation element 280 as first detection information. The second pulse signal 940 can be input to the crosstalk cancellation element 280 as second detection information.

[0134] In addition, the signal converter 260 can allow detection information to be shared between multiple channels.

[0135] For example, any one of multiple detection signal converters can provide detection information to channels other than its own.

[0136] In an example embodiment, the first detection signal converter 261 can send a first pulse signal 930 to the second masking unit 282 disposed in the second channel "Channel B". Additionally, the second detection signal converter 262 can send a second pulse signal 940 to the first masking unit 281 disposed in the first channel "Channel A". The shared pulse signal can be used to identify and eliminate crosstalk.

[0137] The crosstalk cancellation element 280 may include a plurality of masking units that identify crosstalk in the pulse signal output by the signal converter 260 and mask the identified crosstalk.

[0138] In an example embodiment, the crosstalk cancellation element 280 may include a first masking unit 281 connected to the first detection signal converter 261 and a second masking unit 282 connected to the second detection signal converter 262.

[0139] Crosstalk cancellation element 280 can calculate whether crosstalk is included in the pulse signal output from signal converter 260. In an example embodiment, crosstalk cancellation element 280 can 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 timing of the received pulses.

[0140] Determining whether crosstalk is included in the detection information can be performed in each masking unit included in the crosstalk cancellation element 280.

[0141] When the crosstalk cancellation element 280 calculates that crosstalk is included in the detection information, it can identify the crosstalk in the pulse signal provided by the signal converter 260.

[0142] exist Figure 9 In this process, the second masking unit 282 can also receive the second pulse signal 940 from the second detection signal converter 262. The second masking unit 282 can determine that the pulses included in the second pulse signal 940 that correspond to the pulses included in the first pulse signal 930 are crosstalk. The second masking unit 282 can identify the crosstalk in the second pulse signal 940 based on the pulses included in the first pulse signal 930. The second masking unit 282 can identify the crosstalk in the second pulse signal 940 based on at least one of the reception time point, pulse width, and pulse size of the pulses included in the first pulse signal 930. Because the pulses included in the first pulse signal 930 are generated when the first optical detection element 222a receives the first light L1, the reception time point of the pulses included in the first pulse signal 930 can have the same meaning as the first reception time point when the first optical detection element 222a receives the first light L1. Similarly, since the pulse included in the second pulse signal 940 is generated when the second optical detection element 222b receives the first light L1, the receiving time point of the pulse included in the second pulse signal 940 can have the same meaning as the second receiving time point when the second optical detection element 222b receives the first light L1.

[0143] In an example embodiment, the second masking unit 282 can determine, based on the first reception time point of the first light L1 included in the first pulse signal 930, that the pulses received between a time point earlier than the first reception time point and a time point later than the first reception time point are crosstalk caused by the first light L1.

[0144] The crosstalk cancellation element 280 can identify crosstalk in the detection information and then cancel the identified crosstalk.

[0145] exist Figure 9In this process, the second masking unit 282 can determine the start time point for crosstalk cancellation. The second masking unit 282 can compare the first reception time point of the first light L1 detected by the first optical detection element with the second reception time point of the first light L1 detected by the second optical detection element. The second masking unit 282 can determine the earlier of the first and second reception time points as the start time point for crosstalk cancellation.

[0146] The second masking unit 282 can eliminate pulses within a predetermined masking pulse width starting from the elimination start time point from the pulses included in the second pulse signal 940. In this case, the masking pulse width can be set to be greater than the pulse width of the light emitted by the light emitter 100. (Refer to...) Figure 10A and Figure 10B The methods for crosstalk identification and elimination are described in more detail.

[0147] When the detected information includes crosstalk, the crosstalk cancellation element 280 can eliminate the crosstalk and output the detected information. The information output by the crosstalk cancellation element 280 can be output information.

[0148] Furthermore, multiple time counters 249 can use the output information to measure the Time-of-Flight (ToF) of light. Additionally, the processor 300 can obtain information about the object OBJ based on the ToF of light calculated by the time counters 249. Because the processor 300 uses detection information with crosstalk eliminated to obtain information about the object OBJ, the LiDAR device 1000 according to the example embodiment can more accurately measure the position, shape, etc., of the object OBJ.

[0149] In addition, Figure 9 This description only addresses crosstalk occurring between the first optical detection element 222a and the second optical detection element 222b, but the embodiments are not limited thereto. Depending on the shape of the object OBJ, the number of optical detection elements experiencing crosstalk can be increased. In this case, the second detection information may refer to detection information including crosstalk, and the first detection information may refer to detection information used to eliminate crosstalk from the second detection information.

[0150] Figure 10A and Figure 10B It is used to describe the use Figure 9 The diagram shows the crosstalk identification and elimination methods for the first and second detection information.

[0151] Reference Figure 10A and Figure 10B The second masking unit 282 can identify the crosstalk included in the second detection information 1020 based on the first reception time point T1 of the first light L1 included in the first detection information 1010.

[0152] In addition, such as Figure 8A and Figure 8B Similarly, the first light L1 generated by the first light source 110a and emitted toward the object OBJ can be sent to the first light detection element 222a via the first path "path 1", and can be sent to the second light detection element 222b via the third path "path 3". In this case, depending on the shape of the object OBJ, the distance of the first path "path 1" can be greater than or less than the distance of the third path "path 3". Therefore, the first reception time T1 of the first light L1 detected by the first light detection element 222a can be greater than or less than the second reception time T2 of the first light L1 detected by the second light detection element 222b.

[0153] Figure 10A This illustrates the case where the first reception time point T1 is earlier than the second reception time point T2, and... Figure 10B This illustrates the case where the first reception time point T1 is later than the second reception time point T2.

[0154] The second masking unit 282 can determine the pulses 1030 received between a time point T1-Tp that is a predetermined time Tp earlier than the first reception time point T1 and a time point T1+Tp that is a predetermined time Tp later than the first reception time point T1 as crosstalk, based on the first reception time point T1.

[0155] After identifying crosstalk, the second masking unit 282 can determine the crosstalk cancellation start time point Ts. The second masking unit 282 can compare the first reception time point T1 of the first light L1 detected by the first optical detection element 222a with the second reception time point T2 of the first light L1 detected by the second optical detection element. The second masking unit 282 can determine the earlier of the first reception time point T1 and the second reception time point T2 as the crosstalk cancellation start time point Ts.

[0156] like Figure 10A As shown, when the first reception time point T1 is earlier than the second reception time point T2, the second masking unit 282 can determine the first reception time point T1 as the elimination start time point Ts. On the other hand, as... Figure 10B As shown, when the first receiving time point T1 is later than the second receiving time point T2, the second masking unit 282 can determine the second receiving time point T2 as the elimination start time point Ts.

[0157] The second masking unit 282 can eliminate pulses located within a predetermined masking pulse width pw starting from the elimination start time point Ts from the pulses included in the second detection information 1020.

[0158] like Figure 10AAs shown, considering the difference td between the first receiving time point T1 and the second receiving time point T2 of the path of the first light L1, the masking pulse width pw can be set to be greater than the pulse width of the first light L1 emitted by the first light source 110a.

[0159] Figure 11 An example of crosstalk occurring is shown.

[0160] Reference Figure 11 An example is shown of a first current signal 1110 output by a first photodetector 222a and a second current signal 1120 output by a second photodetector 222b.

[0161] The first point 1110a is the point where the first photodetector 222a receives the first light L1, and the first photodetector 222a outputs a current higher than the threshold level at the first point 1110a.

[0162] The second point 1120a is the point where the second photodetector 222b receives the first light L1, and the current signal output from the second photodetector 222b at the second point 1120a corresponds to crosstalk. The current signal output by the second photodetector 222b at the second point 1120a is less than the current signal output by the first photodetector 222a at the first point 1110a, but has a current level higher than the threshold level, and is therefore converted into a pulse signal.

[0163] The third point 1120b is the point where the second optical detection element 222b receives the second light L2, and the current signal output by the second optical detection element 222b at the third point 1120b needs to be changed into a pulse signal for the ToF calculation of the second light L2.

[0164] The second current signal 1120 output by the second photodetector 222b is converted into a pulse signal and used for the Time-of-Flight (ToF) calculation of the second light L2, but as Figure 11 As shown, crosstalk is included in the second current signal 1120, which may prevent the LiDAR device 1000 from accurately calculating the Time-of-Flight (ToF) of the second light L2. Therefore, errors occur in the information about the object OBJ analyzed by the LiDAR device 1000.

[0165] In order to analyze information about object OBJ more accurately, the LiDAR device 1000 according to the example embodiment eliminates crosstalk from the second detection information output by the second optical detection element 222b based on the first detection information output by the first optical detection element 222a.

[0166] Figure 12 An example of eliminating crosstalk by masking pulses is shown.

[0167] Reference Figure 12 The LiDAR device 1000 can convert the first current signal 1110 output by the first photodetector 222a and the second current signal 1120 output by the second photodetector 222b into a first pulse signal and a second pulse signal 1210, respectively.

[0168] The second masking unit 282 identifies crosstalk in the second pulse signal 1210 based on at least one of the pulse reception time, pulse width, and pulse size included in the first pulse signal.

[0169] The second masking unit 282 calculates the elimination start time point Ts for eliminating crosstalk, and eliminates pulses located within a predetermined masking pulse width pw starting from the elimination start time point Ts.

[0170] The second masking unit 282 outputs a masking pulse 1230 having a predetermined masking pulse width pw starting from the elimination start time point Ts, and uses the masking pulse 1230 to eliminate pulses corresponding to crosstalk from the second pulse signal 1210. For this purpose, the second masking unit 282 may include gate circuits.

[0171] The second masking unit 282 outputs a crosstalk-free pulse 1220, and the processor 300 uses the crosstalk-free pulse 1220 to obtain information about the object OBJ. Therefore, the LiDAR device 1000 according to the example embodiment can obtain more accurate information about the object OBJ.

[0172] Figure 13 This is a flowchart illustrating a method for operating a LiDAR device according to an example embodiment.

[0173] Reference Figure 13 The light emitter 100 may include multiple light sources and emits light generated from the multiple light sources toward the object (S1310).

[0174] The light emitter 100 uses a point scanning method to scan point light on the object OBJ, and scans the entire area of ​​the object OBJ using multiple light sources. To this end, the light emitter 100 may include a beam steering element 180 that changes the aiming direction of the multiple light sources, such that the light generated by the multiple light sources is aimed at the object OBJ at different emission angles or at the same emission angle.

[0175] The light receiver 200 can detect the reflected light emitted toward the object OBJ through multiple light detection elements 222 (S1320).

[0176] To improve the ability to receive reflected light, the light detection element 222 may include an avalanche photodiode (APD) or a single-photon avalanche diode (DAD), but the embodiments are not limited thereto.

[0177] Furthermore, depending on the shape of the object OBJ, any one of the multiple photodetectors 222 may receive multiple reflected beams. One of these reflected beams may correspond to crosstalk, thereby causing errors in the position and shape analysis of the object OBJ.

[0178] According to an example embodiment, the LiDAR device 1000 can convert detection information output by a plurality of photodetectors 222 into pulse wave signals to eliminate crosstalk.

[0179] Reference Figure 14 This describes a method for receiving reflected light and converting detection information into a pulse signal when crosstalk occurs.

[0180] The optical receiver 200 can eliminate crosstalk from the second detection information output by at least one of the remaining optical detection elements based on the first detection information output by any one of the multiple optical detection elements (S1330).

[0181] In this case, the second detection information may refer to the detection information output by the photodetector 222 that receives multiple reflected light. Additionally, the first detection information is used to eliminate crosstalk included in the second detection information, and may be different from the second detection information.

[0182] In an example embodiment, the optical receiver 200 can determine whether 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 pulse reception time. Furthermore, when the optical receiver 200 calculates that crosstalk is included in the second detection information, the optical receiver 200 can identify the crosstalk in the second detection information. Additionally, the optical receiver 200 can eliminate the identified crosstalk.

[0183] Reference Figure 15 Describe the methods for calculating whether crosstalk is included and the methods for identifying crosstalk, and refer to... Figure 16 Describe methods for eliminating crosstalk.

[0184] The processor 300 can use the detection information with crosstalk eliminated to obtain information about the object OBJ (S1340).

[0185] The processor 300 can use the first detection information and the second detection information after crosstalk has been eliminated to obtain information about the object OBJ.

[0186] The processor 300 can calculate the distance to the object OBJ based on the ToF of the light detected by the light receiver 200, and perform data processing for analyzing the position and shape of the object OBJ.

[0187] Figure 14 This is a flowchart illustrating a method for detecting reflected light using multiple photodetector elements.

[0188] Reference Figure 14 The light receiver 200 uses the first light detection element 222a to receive the first light L1 emitted from the first light source 110a, which is one of a plurality of light sources, toward the object OBJ via the first path "path 1" to output the first detection information (S1410).

[0189] Additionally, the light receiver 200 can use the second light detection element 222b to receive the second light L2 emitted toward the object OBJ from the second light source 110b, which is different from the first light source 110a, via the second path "path 2" (S1420).

[0190] In this case, the first optical detection element 222a and the second optical detection element 222b are used only to distinguish the optical detection elements receiving light, and they may not be adjacent optical detection elements.

[0191] Furthermore, if crosstalk occurs, the optical receiver 200 uses the second optical detection element 222b to receive the first light L1 emitted from the first light source 110a toward the object OBJ via a third path "path 3" that is different from the first path "path 1", in order to output the second detection information (S1430).

[0192] In the second detection information output by the second optical detection element 222b, the information about the first light L1 can correspond to crosstalk.

[0193] The optical receiver 200 can convert the first detection information output by the first optical detection element 222a into a first pulse signal in the form of a pulse wave to eliminate crosstalk included in the second detection information (S1440).

[0194] In addition, the optical receiver 200 can convert the second detection information output by the second optical detection element 222b into a second pulse signal in the form of a pulse wave (S1450).

[0195] The first pulse signal can be sent to the crosstalk cancellation element 280 through the first channel "Channel A". The second pulse signal can be sent to the crosstalk cancellation element 280 through the second channel "Channel B".

[0196] The optical receiver 200 allows for the sharing of detection information among multiple channels. Therefore, a first pulse signal can be provided to the second channel "Channel B," and a second pulse signal can be provided to the first channel "Channel A." The shared pulse signals can be used to identify and eliminate crosstalk.

[0197] The optical receiver 200 can identify crosstalk in the second pulse signal based on the first pulse signal and eliminate crosstalk from the second pulse signal.

[0198] Figure 15 This is a flowchart illustrating a method for identifying crosstalk in detection information output by multiple optical detection elements, according to an example embodiment.

[0199] In an example embodiment, operations S1510 to S1520 may be performed before the detection information is converted into a pulse signal. In another embodiment, operations S1510 to S1520 may be performed after the detection information is converted into a pulse signal.

[0200] Reference Figure 15 The optical receiver 200 can determine whether crosstalk is included in the second detection information (S1510). In an example embodiment, the optical receiver 200 can determine whether 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 pulse reception time.

[0201] For example, when the number of pulses included in the second detection information is two or more, the optical receiver 200 can determine that the second detection information includes crosstalk, but the embodiments are not limited thereto.

[0202] When the optical receiver 200 calculates that crosstalk is included in the second detection information, the optical receiver 200 can identify the crosstalk in the second detection information. In order to identify the crosstalk in the second detection information, the optical receiver 200 can use the first detection information.

[0203] The optical receiver 200 can identify crosstalk in the second detection information based on the pulses included in the first detection information. The optical receiver 200 can identify crosstalk in the second detection information based on at least one of the reception time point, pulse width, and pulse size of the pulses included in the first detection information.

[0204] In an example embodiment, the optical receiver 200 can calculate pulses with a pulse width greater than a predetermined pulse width among the pulses included in the first detection information as pulses caused by the first light L1. Alternatively, the optical receiver 200 can calculate pulses with a pulse width greater than a predetermined pulse width among the pulses included in the first detection information as pulses caused by the first light L1. In this case, the predetermined pulse width and pulse size can be set based on the output of the optical transmitter 100.

[0205] In another example embodiment, the optical receiver 200 may calculate the pulse with the largest pulse width among the pulses included in the first detection information as the pulse caused by the first light L1. According to another example embodiment, the optical receiver 200 may calculate the pulse with the largest pulse size among the pulses included in the first detection information as the pulse caused by the first light L1.

[0206] The optical receiver 200 can identify crosstalk included in the second detection information based on the pulse information of the first light L1 included in the first detection information.

[0207] The optical receiver 200 can identify crosstalk included in the second detection information based on the first reception time point of the first light L1 included in the first detection information.

[0208] Depending on the shape of the object OBJ, the first receiving time point of the first light L1 detected by the first light detection element 222a may be earlier or later than the second receiving time point of the first light L1 detected by the second light detection element 222b.

[0209] Therefore, the optical receiver 200 can determine the pulses received between a time point that is a predetermined time earlier than the first reception time point and a time point that is a predetermined time later than the first reception time point as crosstalk, based on the first reception time point.

[0210] The optical receiver 200 can eliminate crosstalk identified in the second detection information (S1520).

[0211] Figure 16 This is a flowchart illustrating a method for eliminating crosstalk in detection information output by multiple optical detection elements.

[0212] Reference Figure 16 The optical receiver 200 can calculate the earlier of the first reception time point of the first light L1 detected by the first optical detection element and the second reception time point of the first light L1 detected by the second optical detection element as the crosstalk cancellation start time point (S1610).

[0213] The optical receiver 200 can compare the first reception time point of the first light L1 detected by the first optical detection element 222a with the second reception time point of the first light L1 detected by the second optical detection element 222b.

[0214] Depending on the shape of the object OBJ, the first reception time point of the first light L1 detected by the first photodetector 222a may be earlier or later than the second reception time point of the first light L1 detected by the second photodetector 222b. Therefore, in order to completely eliminate crosstalk, the earlier of the first and second reception time points needs to be set as the crosstalk elimination start time point. For example, when the first reception time point is earlier than the second reception time point, the optical receiver 200 can determine the first reception time point as the elimination start time point. On the other hand, when the first reception time point is later than the second reception time point, the optical receiver 200 can determine the second reception time point as the elimination start time point.

[0215] The optical receiver 200 can eliminate pulses located within a predetermined masking pulse width starting from the elimination start time point from the pulses included in the second pulse signal (S1620).

[0216] The optical receiver 200 can output a masking pulse with a predetermined masking pulse width at the cancellation start time point, and use the masking pulse to eliminate pulses corresponding to crosstalk from the second pulse signal. For this purpose, the optical receiver 200 may include gate circuits.

[0217] Furthermore, the optical receiver 200 can output a second pulse signal with crosstalk eliminated, and the processor 300 can use the crosstalk-eliminated second pulse to obtain information about the object OBJ.

[0218] As described above, even when the LiDAR device 1000 according to the example embodiment includes multiple light sources and multiple light detection elements that receive light emitted from the multiple light sources to achieve high image resolution within a given frame time, the LiDAR device 1000 can more accurately analyze the position and shape of the object OBJ by eliminating crosstalk between the multiple light detection elements.

[0219] Furthermore, the above-described example embodiments can be written as programs executable on a computer and implemented in a general-purpose digital computer for operating the program using a computer-readable recording medium. Additionally, the structure of the data used in the above example embodiments can be recorded on a computer-readable recording medium in various ways. Computer-readable recording media can include storage media such as magnetic storage media (e.g., ROM, floppy disk, hard disk, etc.) and optical reading media (e.g., CD-ROM, DVD, etc.).

[0220] It should be understood that the exemplary embodiments described herein should be considered only in a descriptive sense and not for limiting purposes. The description of features or aspects in each exemplary embodiment should typically be regarded as other similar features or aspects that can be used in other embodiments.

[0221] Although exemplary embodiments have been described with reference to the accompanying drawings, those skilled in the art will understand that various changes in form and detail may be made without departing from the spirit and scope defined by the claims.

Claims

1. A light detection and ranging LiDAR device, comprising: A light emitter includes multiple light sources, including a first light source and a second light source, wherein the second light source is different from the first light source, and each of the multiple light sources is configured to emit light toward an object; A light receiver includes a plurality of light detection elements, the plurality of light detection elements including a first light detection element and a second light detection element, each of the plurality of light detection elements being configured to detect reflected light reflected from the object illuminated by light emitted by the plurality of light sources; as well as The processor is configured to obtain information about the object. The first photodetector is configured to receive first reflected light reflected from the object illuminated by first light emitted by the first light source among the plurality of light sources, and to output first detection information corresponding to the first reflected light. The second photodetector is configured to receive second reflected light reflected from the object illuminated by a second light emitted by the second light source among the plurality of light sources, and to output second detection information based on the second reflected light and generated crosstalk, the crosstalk being generated based on the first reflected light received by the second photodetector. The optical receiver further includes: A first detection signal converter is configured to convert the first detection information output by the first optical detection element into a first pulse signal; The second detection signal converter is configured to convert the second detection information output by the second photodetector into a second pulse signal; and A crosstalk cancellation element is configured to receive the first detection information and the second detection information, identify crosstalk in the second detection information based on the first detection information, and eliminate the identified crosstalk from the second detection information. The crosstalk cancellation element is configured to determine the earlier of the first reception time point of the first reflected light detected by the first optical detection element and the second reception time point of the first reflected light detected by the second optical detection element as the crosstalk cancellation start time point. Eliminate pulses located within a predetermined masking pulse width starting from the elimination start time point from the pulses included in the second pulse signal, and The processor obtains information about the object based at least on second detection information that has eliminated crosstalk.

2. The LiDAR device according to claim 1, wherein, The predetermined masking pulse width is set to be greater than the pulse width of the first reflected light.

3. The LiDAR device according to claim 1, wherein, The light emitter further includes a beam steering element configured to adjust the emission direction of light emitted by each of the plurality of light sources to scan the object.

4. The LiDAR device according to claim 3, wherein, The beam steering element is configured to control the emission direction of light emitted by each of the plurality of light sources by mechanical rotation.

5. The LiDAR device according to claim 1, wherein, The optical receiver further includes a plurality of counters configured to count the time of flight of light detected by each of the plurality of optical detection elements.

6. The LiDAR device according to claim 1, wherein, The processor is also configured to: obtain the distance to the object based on the time of flight of the light detected by each of the plurality of photodetectors, and analyze the position and shape of the object.

7. A method for operating a light-detecting and ranging LiDAR device, the method comprising: Light is emitted toward an object from multiple light sources, including a first light source and a second light source, wherein the second light source is different from the first light source; The reflected light reflected from the object illuminated by light emitted by the plurality of light sources is detected by a plurality of light detection elements, the plurality of light detection elements including a first light detection element and a second light detection element; The first light detection element receives first reflected light reflected from the object illuminated by first light emitted by the first light source among the plurality of light sources, and outputs first detection information corresponding to the first reflected light; The second optical detection element receives second reflected light reflected from the object illuminated by second light emitted by the second light source among the plurality of light sources, and outputs second detection information based on the second reflected light and generated crosstalk, the crosstalk being generated based on the first reflected light received by the second optical detection element; The crosstalk cancellation element receives the first detection information and the second detection information, identifies crosstalk in the second detection information based on the first detection information, and eliminates the identified crosstalk from the second detection information. as well as Information about the object is obtained at least based on second detection information that has eliminated crosstalk. The detection of the reflected light includes: The first detection information output by the first optical detection element is converted into a first pulse signal; and The second detection information output by the second photodetector is converted into a second pulse signal. Eliminating the crosstalk includes: The earlier of the first reception time point of the first reflected light detected by the first optical detection element and the second reception time point of the first reflected light detected by the second optical detection element is determined as the crosstalk cancellation start time point; and Eliminate pulses located within a predetermined masking pulse width starting from the elimination start time point from the pulses included in the second pulse signal.

8. The method according to claim 7, wherein, The predetermined masking pulse width is set to be greater than the pulse width of the first reflected light and the pulse width of the second reflected light, respectively.

9. The method according to claim 7, further comprising: The flight time of light detected by each of the plurality of optical detection elements is counted.

10. The method according to claim 9, wherein, Obtaining information about the object includes: determining the distance to the object based on the time of flight, and analyzing the object's position and shape.

Images