Rider speed measurement

Abstract

This invention provides a system and method for detecting the velocity of an object using a lidar. [Solution] Separate irradiation lines generated by first and second lasers, angularly separated by a selectable angle of 1 to 15 degrees, are swept across the entire field of view using a scanning mirror, thereby sequentially illuminating objects with a known time delay determined by the angular separation and the movement of the mirror. Reflections from the objects are detected by corresponding detectors, and data from these events are processed to generate positional information for each irradiation. By analyzing the change in object position between acquired data and taking into account a controlled time delay, a velocity measurement of the object is calculated.

Description

Technical Field

[0001]

[0001] Cross - Reference to Related Applications This application claims the benefit of U.S. Provisional Patent Application No. 63 / 739,911, filed on December 30, 2024, which is hereby incorporated by reference in its entirety for all purposes.

Background Art

[0002]

[0002] 3D sensors are components in a variety of rapidly growing fields, including autonomous vehicles, drones, robots, and security applications. A lidar system, in particular, can generate a detailed 3D map of an environment or a part thereof by projecting a light beam and detecting the light reflected from an object. Time - of - flight (ToF) calculations based on the time difference between the emission of the light beam and the detection of its reflection enable the system to determine the distances to various points on the object, thereby creating a "point cloud" representing the 3D environment.

[0003]

[0003] Scanning lidar systems can achieve high angular resolution at a relatively affordable price, making them suitable for high - volume market applications. Examples of scanning lidar systems are described in U.S. Patent No. 10,690,754, issued on June 23, 2020, and U.S. Patent Application No. 18 / 531,507, filed on December 6, 2023, which are hereby incorporated by reference in their entirety for all purposes. However, improved scanning systems, devices, and / or methods are desired.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

[0005]

[0004] In a particular configuration, a system for detecting the velocity of an object using a lidar includes: a first laser configured to generate a first illumination line in a field of view; a second laser configured to generate a second illumination line in a field of view, the second illumination line being angularly separated from the first illumination line by a known angle, the known angle being between 1 and 15 degrees; a scanning mirror configured to sweep the first and second illumination lines across the entire field of view, wherein an object in the field of view is illuminated by the first illumination line and then by the second illumination line with a known time delay, the known time delay being a function of the known angle and the angular velocity of the scanning mirror; and a first detector configured to detect a first reflection of the first laser from the object. The system comprises an output device, a second detector configured to detect a second reflection from an object by a second laser, and / or a processing unit configured to generate a first sub-image of an object based on data detected from the reflection by the first laser, including detecting the first reflection, the first sub-image being a first point cloud; generate a second sub-image of an object based on data detected from the reflection by the second laser, including detecting the second reflection, the second sub-image being a second point cloud; and / or calculate a three-dimensional velocity vector of an object by analyzing the change in the object's position and a known time delay between the first sub-image and the second sub-image. In some cases, the first laser is part of a first laser array, the second laser is part of a second laser array, the first and second laser arrays share a focusing lens, the first laser array, the second laser array, the first detector, the second detector, and the processing unit are on the same chip, and / or the scanning mirror is a vibrating mirror or a rotating polyhedron mirror.

[0006]

[0005] In a particular configuration, a system for detecting the velocity of an object using a lidar includes a first laser configured to generate a first illumination line in a field of view, a second laser configured to generate a second illumination line in a field of view, the second illumination line being angularly separated from the first illumination line by a known angle, and a scanning mirror configured to sweep the first and second illumination lines across the entire field of view, wherein an object in the field of view is illuminated by the first illumination line, then by the second illumination line with a known time delay, and for a known time The delay comprises a scanning mirror based on a known angle, a first detector configured to detect a first reflection of a first laser from an object, a second detector configured to detect a second reflection of a second laser from an object, and / or a processing unit configured to calculate a first position of the object based on the detection of the first reflection, a second position of the object based on the detection of the second reflection, and / or calculate the velocity of the object based on the difference between the first position, the second position and a known time delay. In some configurations, the known angle is between 1 and 15 degrees, the known time delay is a function of the known angle and the angular velocity of the scanning mirror, the processing unit is further configured to calculate the three-dimensional velocity vector of the object by analyzing the change in the object's position between a first sub-image generated from the data of the first reflection and a second sub-image generated from the data of the second reflection, the first laser is part of a first laser array, the second laser is part of a second laser array, the first and second laser arrays share a focusing lens, the first laser array, the second laser array, the first detector, the second detector, and the processing unit are on the same chip, and the scanning mirror is a vibrating mirror or a rotating polyhedron mirror.

[0007]

[0006] In a particular embodiment, a method for detecting the velocity of an object using a lidar includes: emitting light from a first laser configured to generate a first illumination line; emitting light from a second laser configured to generate a second illumination line, the second illumination line being angularly separated from the first illumination line by a known angle; sweeping the first and second illumination lines across a field of view using a scanning mirror, such that an object in the field of view is illuminated by the first illumination line and then by the second illumination line with a known time delay; detecting reflections of the first and second illumination lines from an object using at least one detector array; calculating a first position of the object based on the reflection of the first illumination line; calculating a second position of the object based on the reflection of the second illumination line; and / or calculating the velocity of the object based on the difference between the first position, the second position, and the known time delay. In some configurations, the known angle is between 1 and 15 degrees, the known time delay is a function of the known angle and the angular velocity of the scanning mirror, the method further comprises calculating the three-dimensional velocity vector of an object by analyzing the change in the object's position between a first sub-image generated from data of a first reflection and a second sub-image generated from data of a second reflection, the first laser is part of a first laser array, the second laser is part of a second laser array, the first and second laser arrays share a focusing lens, the first laser array, the second laser array, the first detector, the second detector, and the processing unit are on the same chip, and / or the scanning mirror is a vibrating mirror or a rotating polyhedron mirror.

[0008]

[0007] In some configurations, the system for the LiDAR includes a first laser source configured to emit light of a first wavelength, a second laser source configured to emit light of a second wavelength different from the first wavelength, a scanning mirror configured to scan light from the first laser source over an entire first field of view, scan light from the second laser source over an entire second field of view, and receive reflected light from the first and second fields of view, a beam splitter positioned to receive reflected light from the scanning mirror and configured to separate the reflected light into a first optical path corresponding to a first wavelength and a second optical path corresponding to a second wavelength, a first detector positioned in the first optical path for detecting reflected light of the first wavelength, and / or a second detector positioned in the second optical path for detecting reflected light of the second wavelength. In some configurations, the system further comprises a first lens having a first focal length in a first optical path and / or a second lens having a second focal length in a second optical path, wherein the second focal length is longer than the first focal length. In certain configurations, the first optical path is optimized for a first detection range and a first field of view, the second optical path is optimized for a second detection range and a second field of view, wherein the second detection range is longer than the first detection range, the second field of view is narrower than the first field of view, the first and second wavelengths are 850 nm to 960 nm, the first wavelength is 905 nm plus or minus 10 nm, the second wavelength is 940 nm plus or minus 10 nm, and / or the system further comprises a processing unit configured to generate a three-dimensional point cloud by combining data from at least a first detector and a second detector.

[0009]

[0008] In a particular configuration, the method for the LiDAR to detect near and far objects is to emit a first laser pulse in a first field of view, the first laser pulse characterized by a first wavelength; to emit a second laser pulse in a second field of view, the second laser pulse characterized by a second wavelength; to receive reflected light from the first and second fields of view; and to route the reflected light through a first optical path corresponding to the first wavelength and a second optical path corresponding to the second wavelength. The method includes separating the light into a second optical path, detecting reflected light of a first wavelength using a first detector located in the first optical path, detecting reflected light of a second wavelength using a second detector located in the second optical path, calculating a first distance to a first object in the first field of view based on the first detector detecting reflected light corresponding to the first wavelength, and / or calculating a second distance to a second object in the second field of view based on the second detector detecting reflected light corresponding to the second wavelength. In a particular configuration, the method further includes passing light of a first wavelength through a first lens having a first focal length, the first lens being located in the first optical path, and passing light of a second wavelength through a second lens having a second focal length, the second lens being located in the second optical path.

[0010]

[0009] In certain configurations, a method for measuring distance using a LiDAR system includes: emitting a first laser pulse toward a first field of view; emitting a second laser pulse toward a second field of view; initiating a first time-of-flight measurement to calculate a first distance to a first object in the first field of view in response to detecting a reflection of the laser pulse from a first detector; waiting for a predetermined time delay after emitting the second laser pulse but before detecting a reflection of the second laser pulse; initiating a second time-of-flight measurement based on the reflection of the second laser pulse; and / or calculating a second distance to a second object in the second field of view based on the second time-of-flight measurement, wherein the second range is further from the LiDAR system than the first range. In some configurations, the predetermined time delay corresponds to the round-trip propagation time of light to a minimum distance in the second field of view, the minimum distance in the second range is 250 meters or more, and / or the first and second fields of view overlap at least partially.

[0011]

[0010] Further areas of applicability of this disclosure will become apparent from the detailed description provided below. The detailed description and specific examples illustrate various embodiments, but should be understood to be for illustrative purposes only and not intended to limit the scope of this disclosure.

[0012]

[0011] This disclosure will be explained in conjunction with the attached drawings. [Brief explanation of the drawing]

[0013] [Figure 1] This document shows one embodiment of a LiDAR sensor for 3D imaging. [Figure 2] This describes one embodiment of a lidar system that uses two different wavelengths to simultaneously measure shorter and longer distances. [Figure 3] Figure 2 is an illustrative schematic representation of the two fields of view of the dual-wavelength lidar system. [Figure 4]This is a schematic diagram of one embodiment of a lidar system configured for high-speed velocity measurement, utilizing two angle-separated laser arrays. [Figure 5] Figure 4 is a graph showing the relationship between the angular separation, distance measurement accuracy, and minimum resolution of the laser array in an exemplary LiDAR system. [Figure 6] A flowchart illustrating one embodiment of the process by which a lidar detects nearby and distant objects is shown. [Figure 7] A flowchart illustrating one embodiment of the process of measuring long distances using a LiDAR system is shown. [Figure 8] A flowchart of one embodiment of the process of detecting the velocity of an object using a lidar is shown. [Modes for carrying out the invention]

[0014]

[0020] In the accompanying drawings, similar components and / or features may have the same reference label. Furthermore, various components of the same type may be distinguished by following the reference label with a dash and a second label that distinguishes the similar components. Where only the first reference label is used herein, the description is applicable to any similar component having the same first reference label, regardless of the second reference label.

[0015]

[0021] The following description provides exemplary embodiments and is not intended to limit the scope, applicability, or configuration of the Disclosure. Rather, the following description of preferred exemplary embodiments provides a possible description for carrying out the preferred exemplary embodiments to those skilled in the art. It will be understood that various modifications may be made to the function and arrangement of the elements without departing from the spirit and scope set forth in the appended claims.

[0016]

[0022] Additional examples of lidar systems are described in U.S. Patent Application No. 18 / 787,427, filed July 29, 2024, and U.S. Patent Application No. 19 / 027,522, filed January 17, 2025, both of which are incorporated by reference for all purposes.

[0017]

[0023] This disclosure generally relates to scanning lidar systems. By way of example, some embodiments relate to using two different wavelengths for short-range sensing and long-range sensing, using time delays to measure longer distances, and / or using two lasers separated by a number of degrees to extract velocity measurements.

[0018]

[0024] FIG. 1 shows one embodiment of a lidar sensor 100 for three-dimensional imaging. The lidar sensor 100 includes a light-emitting lens 130 and a light-receiving lens 140. The lidar sensor 100 includes a light source 110-a disposed substantially at the rear focal plane of the light-emitting lens 130. The light source 110-a is operable to emit light pulses 120 from respective light-emitting positions within the rear focal plane of the light-emitting lens 130. The light-emitting lens 130 is configured to collimate the light pulses 120 and direct them toward an object 150 located in front of the lidar sensor 100. For a given light-emitting position of the light source 110-a, the collimated light pulse 120’ is directed at a corresponding angle toward the object 150.

[0019]

[0025] A portion 122 of the collimated light pulse 120’ is reflected from the object 150 toward the light-receiving lens 140. The light-receiving lens 140 is configured to focus a portion 122’ of the light pulse reflected from the object 150 to a corresponding detection position within the focal plane of the light-receiving lens 140. The lidar sensor 100 further includes a detector 160-a disposed substantially at the focal plane of the light-receiving lens 140. The detector 160-a is configured to receive and detect a portion 122’ of the light pulse 120 reflected from the object at the corresponding detection position. The corresponding detection position of the detector 160-a is optically conjugate with each light-emitting position of the light source 110-a.

[0020]

[0026] The light pulse 120 may have a short duration and may have a pulse width of, for example, 10 ns. The lidar sensor 100 further includes a processor 190 coupled to the light source 110-a and the detector 160-a. The processor 190 is configured to determine the time of flight (TOF) of the light pulse 120 from emission to detection. Since the light pulse 120 propagates at the speed of light, the distance between the lidar sensor 100 and the object 150 may be determined based on the determined time of flight.

[0021]

[0027] One method for scanning a laser beam (e.g., light pulse 120') across the entire FOV is to move the light source 110-a laterally relative to the light source 130 within the back focal plane of the light source 130. For example, the light source 110-a may be raster scanned for multiple emission positions in the back focal plane of the light source 130, as shown in Figure 1. The light source 110-a may emit multiple light pulses at multiple emission positions. Each light pulse emitted at each emission position is collimated by the light source 130 and guided toward the object 150 at a respective angle, colliding with a corresponding point on the surface of the object 150. Thus, when the light source 110-a is raster scanned within a specific region within the back focal plane of the light source 130, the corresponding region on the object 150 is scanned. As shown in Figure 1, the detector 160-a may be raster scanned to be positioned at multiple corresponding detection positions within the focal plane of the light receiving lens 140. The scanning of detector 160-a is typically performed in synchronization with the scanning of light source 110-a, and as a result, detector 160-a and light source 110-a are always optically conjugate to each other at a given time.

[0022]

[0028] The distance from the lidar sensor 100 to each corresponding point on the surface of object 150 may be determined by determining the time of flight of each light pulse emitted at each emission position. In some embodiments, the processor 190 is coupled with a position encoder that detects the position of the light source 110-a at each emission position. Based on the emission position, the angle of the collimated light pulse 120' may be determined. The XY coordinates of the corresponding points on the surface of object 150 may be determined based on the angle and distance to the lidar sensor 100. Thus, a three-dimensional image of object 150 may be constructed based on the measured distances from the lidar sensor 100 to various points on the surface of object 150. In some embodiments, the three-dimensional image may be represented as a point cloud, i.e., as a set of X, Y, and Z coordinates of points on the surface of object 150.

[0023]

[0029] In some embodiments, the intensity of the return light pulse 122' is measured and used to adjust the output of subsequent light pulses from the same light source in order to prevent detector saturation, improve eye safety, or reduce overall power consumption. The output of the light pulse may be varied by changing the duration of the light pulse, the voltage or current applied to the laser, or the charge stored in a capacitor used to power the laser. In the latter case, the charge stored in the capacitor may be varied by changing the charging time, charging voltage, or charging current to the capacitor. In some embodiments, another dimension may be added to the image using reflectance determined by the intensity of the detected pulse. For example, the image may include X, Y, and Z coordinates, as well as reflectance (or luminance).

[0024]

[0030] The angular field of view (AFOV) of the lidar sensor 100 may be estimated as follows, based on the scanning range of the light source 110-a and the focal length of the light-emitting lens 130.

number

[0025]

[0031] The light source 110-a may be configured to emit light pulses in the near-infrared wavelength range. The energy of each light pulse may be on the order of microjoules, which can be considered safe for the eye at repetition rates in the kHz range. For light sources operating at wavelengths above approximately 1500 nm (near-infrared wavelength range), the energy levels may be higher because the eye does not focus on those wavelengths. The detector 160-a may comprise a silicon avalanche photodiode, a photomultiplier tube, a PIN diode, or other semiconductor sensor.

[0026]

[0032] Additional rida sensors are available for the owner of the following patent applications: U.S. Patent Application No. 15 / 267,558 filed on September 15, 2016; U.S. Patent Application No. 15 / 971,548 filed on May 4, 2018; U.S. Patent Application No. 16 / 504,989 filed on July 8, 2019; U.S. Patent Application No. 16 / 775,166 filed on January 28, 2020; and U.S. Patent Application No. 16 / 775,166 filed on September 25, 2020. The disclosures are described in U.S. Patent Application No. 17 / 032,526, filed December 23, 2020, U.S. Patent Application No. 17 / 133,355, filed March 18, 2021, and U.S. Patent Application No. 17 / 205,792, filed July 20, 2021, and these disclosures are incorporated by reference for any purpose.

[0027]

[0033] In some LiDAR systems, light from a laser array is scanned horizontally across the entire field of view (FOV) by a vibrating mirror. In some configurations, light is projected from the laser array by a light-transmitting lens system (e.g., comprising one or more lenses). Light reflected from objects in the FOV is received by the vibrating mirror and imaged onto a detector array. In some configurations, a light-receiving lens system (e.g., comprising one or more lenses) is used to image the light from the vibrating mirror onto the detector array. The laser array may be a single laser with a VCSEL array or a non-cylindrical optical system for forming a line image. The detector array may be a single monolithic array of silicon single-photon detectors (SPADs) and / or other types of photodetectors such as avalanche photodetectors (APDs). The laser array and detector array are positioned to cover the vertical FOV, thereby allowing the entire FOV to be covered by scanning the array horizontally. In some implementations, a rotating polyhedron mirror may be used instead of a vibrating mirror.

[0028]

[0034] Signals from detectors within the detector array are analyzed by a processing unit, and the time-of-flight (ToF) difference between the laser pulse and the received light is used to determine (e.g., calculate) the distance to an object within the field of view (FOV). Multiple signals from the detectors are used to construct a 3D image of the FOV (e.g., generate a 3D point cloud).

[0029]

[0035] In some situations, it can be difficult to cover both nearby and distant objects with adequate spatial and temporal (e.g., distance) resolution. Furthermore, some ToF designs do not provide instantaneous (or near-instantaneous) information about the velocity of objects.

[0030]

[0036] A. Dual-wavelength architecture for multi-range sensing

[0031]

[0037] Figure 2 shows one embodiment of a lidar system 200 that uses two different wavelengths to simultaneously measure shorter distances in a wider field of view and longer distances in a narrower field of view.

[0032]

[0038] Designing a single optical system that simultaneously provides adequate spatial and distance resolution for both near and far objects can be challenging. Optical configurations optimized for long-range detection may have a narrow field of view (FOV) and insufficient resolution at near range, while wide-FOV systems for near-range sensing may lack the power and resolution to effectively detect distant objects. Figure 2 illustrates an embodiment that overcomes one or more of these challenges. Two sets of lasers with different wavelengths are used, the first set optimized for near range and / or a wide FOV, and the second set optimized for long range and / or a narrower FOV. For example, the second set of lasers may have higher power or be focused into a finer line. For clarity, the lasers and / or transmitting optics are not shown in Figure 2. In the detection path, a beam splitter is used to direct the first wavelength to one set of detectors and the second wavelength to a second set of detectors. The imaging lenses for the second set of detectors may have a longer focal length to improve resolution and / or light collection from longer distances, at which point the field of view (FOV) may be reduced.

[0033]

[0039] In the illustrated example, the LiDAR system 200 uses a first laser 204. The first laser 204 operates at a first wavelength (e.g., peak wavelength 905 nm, ±5 nm). In some configurations, the first laser 204 is part of a first laser array (e.g., the laser array extends in and / or out of the plane of the paper and / or has additional columns). Each laser in the first laser array is configured to operate at a first wavelength. The first laser 204 (and the first laser array, if used) is optimized for short-range detection with a wide field of view (FOV).

[0034]

[0040] The LiDAR system 200 includes a second laser 208. The second laser 208 operates at a second wavelength (e.g., 940 nm, ±5 nanometers). In some configurations, the second laser 208 is part of a second laser array (e.g., the laser array extends in and / or out of the plane of the paper and / or has additional columns). Each laser on the second laser array is configured to operate at the second wavelength. The second laser 208 (and the second laser array, if used) is optimized for long-range detection with a narrow field of view.

[0035]

[0041] Light from the first laser 204 and light from the second laser 208 are sent to the scanning mirror 212, which passes through the IR window 216 and into one or more fields of view of the environment. The scanning mirror 212 can be configured to vibrate back and forth (e.g., around a pivot 218), or it can rotate in a circle (e.g., as part of a polyhedron). An example shown in Figure 2 illustrates a vibrating scanning mirror.

[0036]

[0042] Light from the first laser 204 passes through the beam splitter 220 before it enters the scanning mirror 212. The second laser 208 is reflected by the beam splitter 220 before it enters the scanning mirror 212. The beam splitter 220 can be a "hot" mirror or a "cold" mirror. A hot mirror reflects light with wavelengths longer than the cutoff wavelength, and a cold mirror reflects light with wavelengths shorter than the cutoff wavelength. In the example shown in Figure 2, the beam splitter 220 is a hot mirror that reflects longer wavelengths and transmits shorter wavelengths. For example, a hot mirror acting as a beam splitter 220 has a cutoff wavelength of approximately 920 nanometers, so that wavelengths higher than 920 nanometers are reflected and wavelengths shorter than 920 nanometers are transmitted.

[0037]

[0043] Reflected light from the environment is collected by the scanning mirror 212 and directed toward the beam splitter 220. The beam splitter 220 is configured to transmit light of a first wavelength (e.g., 905 nm) and reflect light of a second wavelength (e.g., 940 nm), or vice versa.

[0038]

[0044] Light of a first wavelength is guided along a first optical path. A first lens 224 is positioned on the first optical path. The first optical path extends from a beam splitter 220 to a first detector 228. Light that has passed through the first lens 224 is imaged onto the first detector 228. The first detector 228 can be part of a first detector array. For example, the first detector array comprises one or more detector rows extending in and / or out of the plane of the paper.

[0039]

[0045] Light of a second wavelength is guided along a second optical path. A second lens 230 is positioned along the second optical path. The second optical path extends from the beam splitter 220 to a second detector 232. Light that has passed through the second lens 230 is imaged onto the second detector 232. The second detector 232 can be part of a second detector array. For example, the second detector array comprises one or more detector rows extending in and / or out of the plane of the paper.

[0040]

[0046] The first optical path is optimized for short-range sensing and provides a wide field of view. The second optical path is optimized for long-range sensing and provides a narrower field of view than the first optical path. The first lens 224 has a shorter focal length than the second lens 230. A longer focal length for the second lens 230 results in higher magnification, improving angular resolution and light collection efficiency for distant objects.

[0041]

[0047] The first lens 224 and the second lens 230 can be simple lenses or optical arrays (for example, optical assemblies having an arrangement of one or more lenses, mirrors, prisms, aperture diaphragms, and other optical components).

[0042]

[0048] The first lens 224 (and by analogy, the second lens) can be used to focus light onto a single detector, onto a single row of the first detector array, or onto multiple rows of the first detector array. In some configurations, light from the first laser 204 also passes through the first lens 224, while in other configurations, light from the first laser 204 passes through a different lens than the first lens 224. In some configurations, light from the second laser 208 also passes through the second lens 230, while in other configurations, light from the second laser 208 passes through a different lens than the second lens 230.

[0043]

[0049] While wavelengths of 905 nm and 940 nm are provided as examples, other wavelengths (e.g., those that can be optically separated) can also be used. For example, light in the range of 850 nm to 960 nm is used. Light with a wavelength of 850 nm is on the boundary between visible and non-visible. The first and second wavelengths of light are characterized by their respective peak wavelengths (for example, the peak wavelength of the first light is 905 nm and the peak wavelength of the second light is 940 nm). In some configurations, the first wavelength is at least 10 nm, 20 nm, or 30 nm away from the second wavelength, and no more than 30 nm, 50 nm, or 60 nm away.

[0044]

[0050] The processing unit 240 is configured to calculate the time of flight from when light is emitted from the laser, reflected by objects in the field of view, and returns to the detector. In some configurations, the detector (and array), the laser (and array), and / or the processing unit are integrated on a single chip. In some configurations, each detector array has its own processing unit.

[0045]

[0051] Figure 3 is an illustrative schematic representation of two fields of view of the LiDAR system 200 shown in Figure 2. Figure 3 shows a first field of view (FOV) 304 and a second FOV 308. The first FOV 304 (e.g., using 905 nm light) is for broader, shorter-distance sensing, while the second FOV 308 (e.g., using 940 nm light) is for narrower, longer-distance sensing.

[0046]

[0052] As shown in Figure 3, this architecture results in two distinct but complementary sensing regions. For example, the first FOV 304 has a horizontal FOV H-1 = 120 degrees, a vertical FOV (in-plane and out-of-plane) of 25°, and an effective range R-1 of 0.1 meters to 300 meters. The second FOV 308 has a narrower horizontal FOV H-2 = 60°, a vertical FOV of 12°, and an effective range R-2 of 200 meters to 500 meters. The system can be designed to have an overlapping region 312 (e.g., 200m to 300m) in which both subsystems can detect objects, enabling sensor fusion and robust performance.

[0047]

[0053] B. Time-delay distance measurement to improve long-range accuracy

[0048]

[0054] Time-delayed ranging can be used to improve the accuracy of long-distance measurements. In ToF systems, complex and / or high-frequency counters are often used to measure long distances with high accuracy. To simplify this, time delays can be used in the measurement process of long-range detectors. The measurement counter is started only after a delay equivalent to the propagation time of light up to the minimum desired range (e.g., a range equal to (or greater than) 200, 225, 250, 255, 260, 270, or 300 meters). This allows the system to use high-resolution counters over a specific, limited long-distance window (e.g., 250m to 500m), improving accuracy without using overly complex designs.

[0049]

[0055] In some configurations, the measurement process for long-range FOV (e.g., the second FOV 308 in Figure 3) is enhanced. For example, in the second detector 232 (and second detector array) in Figure 2, the ToF counter is not started immediately after the laser pulse is emitted from the second laser 208. Instead, the processing unit introduces a fixed time delay before starting the count to detect light at the second detector 232. This delay corresponds to the round-trip time of light up to a minimum threshold distance, e.g., 200 meters or 250 meters. By starting the measurement only after this delay, the system can effectively ignore reflections from objects closer than 200 meters or 250 meters on this channel, allowing the entire dynamic range of the counter to be dedicated to the desired long-range window (e.g., 250m to 500m). This enables higher temporal resolution and, consequently, more accurate distance measurements within that specific range without using overly complex or expensive high-speed counters.

[0050]

[0056] C. Dual-array architecture for speed measurement

[0051]

[0057] Conventional LiDAR systems do not directly measure the velocity of an object. Velocity can be inferred by comparing the object's position across multiple consecutive data frames. Often, one frame represents a single rotation, vibration, or raster scan of a scanning mirror. The time delay between frames can be critical in time-sensitive situations, such as collision avoidance in autonomous vehicles, where near-instantaneous velocity information is highly desirable. Other techniques, such as Frequency Modulated Continuous Wave (FMCW) LiDAR, can directly measure velocity via the Doppler effect, but they often come with their own set of complexities and costs.

[0052]

[0058] Figure 4 is a schematic diagram of one embodiment of a LiDAR system 400 configured for high-speed velocity measurement, utilizing two angularly separated laser arrays. A probe laser is positioned at an angle of several degrees from the main laser for single-frame velocity detection.

[0053]

[0059] The Lider system 400 comprises a first laser 404-1 and a second laser 404-2. The first laser 404-1 may be part of a first laser array (e.g., a laser array extending in and out of the plane of the paper). The second laser 404-2 may be part of a second laser array (e.g., a laser array extending in and out of the plane of the paper). In some configurations, the first laser 404-1 in Figure 4 is the same laser as the first laser 204 in Figure 2, and the second laser 404-2 in Figure 4 is part of the first laser array described in Figure 2, but in a different array from the first laser 204 (e.g., a laser above or below laser 204, and / or one or more laser arrays above or below laser 204). A similar configuration can be used for the second laser 208 in Figure 2 (e.g., a second laser to the left or right of laser 208, or having multiple laser arrays to the left or right of laser 208). The first laser 404-1 is located at a distance d from the second laser 404-2. The first detector 408-1 and the second detector 408-2 are used to detect reflected light from objects in the field of view. Detector 408 can be part of a one-dimensional or two-dimensional detector array. Detector 408 can calculate the distance from the LiDAR system 400 to one or more objects in the field of view. By knowing the orientation and distance information, the LiDAR system 400 can calculate the position of objects in the environment (e.g., relative to the LiDAR system 400).

[0054]

[0060] The Lida System 400 uses two lasers (or two perpendicular lines of illumination) that are physically separated by a distance d, corresponding to small angular separations θ within the FOV (e.g., 1 to 15 degrees, 1 to 10 degrees, or 2 to 6 degrees, i.e., plus or minus 4 degrees, 2 degrees, or 3 degrees).

[0055]

[0061] As the scanning mirror 212 sweeps the laser beam across the entire scene, it effectively acquires two images of the same object separated by a very short, known time interval. The processing unit can then calculate the velocity of the object in one or multiple dimensions by analyzing the change in distance and / or position of the object between these two close measurements. This "in-frame" velocity calculation is significantly faster than conventional "inter-frame" methods and provides time-sensitive data for real-time applications. Two sub-images can be calculated, but the sub-images do not need to be two-dimensional (they may be three-dimensional images / point clouds with distance information using ToF information). In some configurations, a one-dimensional image (meaning scanning in one dimension) is used. In some configurations, only two points are used. For example, the first point from the reflection of the first laser is of an object located 80 meters directly in front of the LiDAR system 400, and the reflection of the second laser is of an object located 60 meters directly in front of the LiDAR system 400. Two points can be used to detect the velocity (of objects and / or the LiDAR system 400) of the LiDAR system 400 in the direction directly in front of it (for example, of a vehicle, for collision avoidance). Depending on the situation, one-dimensional and / or two-dimensional sub-images can provide additional information about the movement of objects. For example, an object moving parallel, perpendicular, or diagonally (not just in front) to the LiDAR system 400 can be tracked and its position and velocity calculated.

[0056]

[0062] The first lens 412-1 is used to shape the beams from the first laser 404-1, the second laser 404-2, or both (in some embodiments, the second laser 404-2 has its own lens). Laser 404 may be part of two vertical laser arrays, or it may be two separate lasers whose beams are shaped into vertical lines by a non-cylindrical optical system. In some configurations, each laser array shares one lens. In some configurations, multiple laser arrays share a lens.

[0057]

[0063] The second lens 412-2 is used to focus reflected light from an object onto the first detector 408-1, the second detector 408-2, or both (in some embodiments, the second detector 408-2 has its own lens). The lens 412 may be a simple lens or may have an optical array. In some configurations, each detector array shares one lens. In some configurations, multiple detector arrays share one lens.

[0058]

[0064] As the scanning mirror 212 sweeps the light from laser 404 (or lines from the two laser arrays) across the entire FOV, they create two distinct data points from detector 408 (or two images if combined with data from other light sources to form a point cloud image). Due to the angular separation θ, the second laser 404-2 illuminates a given point in the scene with a time delay t from the first laser 404-1. This time delay t is a function of the angular separation θ and angular velocity ω of the scanning mirror, and is given by a function such as t = θ / (2ω), or t = θ / ω (for example, in the case of a rotating mirror).

[0059]

[0065] The processing unit analyzes the radial distance r measured for corresponding pixels in two images. The change in radial distance Δr over a known time t allows for the direct calculation of the object's radial velocity (Vr = Δr / t). By identifying the object in the point cloud using recognition software, the system can analyze the change in the object's position in three dimensions (e.g., r, θ, and φ, or x, y, and z) between the two subframe images to calculate its complete 3D velocity vector. Since time t is much shorter than the time used to acquire the two full frames, this method provides velocity information much faster than conventional ToF lidars.

[0060]

[0066] Data and / or images from detector 408 are acquired from the same sweep (e.g., vibration or rotation) of scanning mirror 212. In other words, light from both the first laser 404-1 and the second laser 404-2 is incident on the same mirror while the mirror is rotating in one direction and before the mirror changes direction. Light is detected by the first detector 408-1 and the second detector 408-2 while the mirror is rotating in the (same) one direction (e.g., from reflection, before the mirror changes direction).

[0061]

[0067] Figure 5 is a graph showing the relationship between the angular separation, distance measurement accuracy, and minimum resolvable velocity of the laser array of the exemplary LiDAR system shown in Figure 4.

[0062]

[0068] Figure 5 illustrates some design trade-offs in this system. A larger separation angle θ results in a longer time delay t, allowing for more accurate measurement of objects moving at low speeds. However, larger angles may require more complex optics and a larger scanning range to ensure that the two images perfectly overlap. The accuracy of the velocity measurement may depend on the accuracy of the underlying distance measurement.

[0063]

[0069] θ is typically set between 1 and 15 degrees, with some configurations opting for approximately 4 degrees. This is because, when an object is moving slowly, a small θ (e.g., less than 1 degree) may result in inaccurate velocity calculations. Conversely, for very fast-moving objects such as cars, a large θ may cause the object to be missed. Furthermore, a large θ can reduce the effective field of view. For example, if θ is 15 degrees and the field of view is 90 degrees, the effective field of view becomes 75 degrees. An angular separation (θ) of approximately 4 degrees can provide a balance between these conflicting factors.

[0064]

[0070] In some configurations, more than two lasers 404 (or more than two laser rows or more than two laser arrays) are used. For example, three laser arrays are used to obtain three velocity measurements. In this example, there may be a θ of 4 degrees between the lines of the first and second laser arrays, a θ of 4 degrees between the lines of the second and third laser arrays, and a θ of 8 degrees between the lines of the first and third laser arrays. Velocity measurements can be taken from the differences between the lines of the first and second laser arrays, between the lines of the second and third laser arrays, and between the lines of the first and third laser arrays (to detect slower motion). In some configurations, velocity measurements can be ignored at the periphery (for example, velocity measurements using the first laser array can be discarded in one direction, and velocity measurements using the third laser array can be discarded in the other direction). In this way, the effective field of view can still be the total FOV minus θ (for example, not the total FOV minus 2θ). This results in the discarding of slower velocity detections at the periphery of the field of view, which may be acceptable in some situations.

[0065]

[0071] Figure 4 shows a reciprocating scanning mirror, but it can be replaced with a rotating polyhedron mirror. The mirror can also scan vertically, in which case the laser array is positioned to generate a horizontal irradiation line.

[0066]

[0072] In some cases, the two laser arrays and detector systems may have symmetrical functions, so that when the reciprocating mirror reverses direction, the laser array and detector array that produce the first image produce the second image. In some cases, the two arrays may be optimized for slightly different functions. For example, the first laser and detector array may be optimized for low power, while the second laser and detector array may be optimized for high precision.

[0067]

[0073] The two laser arrays can also be used for additional functions; for example, the first laser array can be used to measure the reflectivity of an object, thereby adjusting the output of the second laser array to avoid detector saturation for bright objects such as retroreflective markers.

[0068]

[0074] Referring now to Figure 6, this is a flowchart of one embodiment of the process 600 in which the LiDAR detects near and far objects. The process 600 is initiated in step 604 by emitting a first laser pulse in a first field of view and a second laser pulse in a second field of view (as shown, for example, in Figures 2 and 3). The first laser pulse is characterized by a first wavelength, and the second laser pulse is characterized by a second wavelength. In some configurations, the emission of the second laser pulse occurs simultaneously with the emission of the first laser pulse. In some configurations, the emission of the second laser pulse occurs 0.00001 seconds, 0.001 seconds, 0.01 seconds, 0.1 seconds, or 0.25 seconds after the emission of the first laser pulse.

[0069]

[0075] In step 608, reflected light from the first and second fields of view is received (for example, by the scanning mirror in Figure 2) and separated (for example, by the beam splitter 220 in Figure 2). The received light is separated into a first optical path corresponding to the first wavelength and a second optical path corresponding to the second wavelength.

[0070]

[0076] In step 612, light of a first wavelength and light of a second wavelength are detected. A first detector (e.g., detector 228 in Figure 2) located in the first optical path detects reflected light of the first wavelength. A second detector (e.g., detector 232 in Figure 2) located in the second optical path detects reflected light of the second wavelength.

[0071]

[0077] In step 616, a first distance to a first object in the first field of view is calculated based on a first detector that detects reflected light corresponding to a first wavelength. In step 620, a second distance to a second object in the second field of view is calculated based on a second detector that detects reflected light corresponding to a second wavelength. In some configurations, the second distance is greater than 150 meters, 200 meters, 250 meters, 300 meters, 350 meters, or 400 meters greater than the first distance.

[0072]

[0078] In some configurations, the method further includes passing light of a first wavelength through a first lens having a first focal length, the first lens being in a first optical path, and / or passing light of a second wavelength through a second lens having a second focal length, the second lens being in a second optical path.

[0073]

[0079] Referring now to Figure 7, this is a flowchart of one embodiment of a process 700 for measuring distance using a LiDAR system. Process 700 begins in step 704 by emitting a first laser pulse into a first field of view and a second laser pulse into a second field of view (similar to step 604 in Figure 6, for example).

[0074]

[0080] In step 708, in response to detecting the reflection of a laser pulse from a first object in the first field of view using a first detector (e.g., detector 228 in Figure 2), a first distance to the first object in the first field of view is calculated using a first time-of-flight measurement.

[0075]

[0081] In step 712, the system waits for a predetermined time delay after the emission of the second laser pulse before detecting the reflection of the second laser pulse using a second detector (e.g., detector 232 in Figure 2). The second time-of-flight measurement is calculated based on the reflection of the second laser pulse detected by the second detector.

[0076]

[0082] In step 716, the second distance to the second object in the second field of view is calculated based on the second time-of-flight measurement. The second range is further from the LiDAR system than the first range.

[0077]

[0083] In some configurations, a predetermined time delay corresponds to the round-trip propagation time of light to the minimum distance of the second field of view, the minimum distance of the second field of view is 250 meters or more, and / or the first and second fields of view overlap at least partially.

[0078]

[0084] Referring now to Figure 8, a flowchart of one embodiment of process 800 for detecting the velocity of an object using a lidar is shown. Process 800 begins in step 804 by emitting light from a first laser and then emitting light from a second laser. Emitting light from the first laser is configured to generate a first irradiation line. Emitting light from the second laser is configured to generate a second irradiation line. The second irradiation line is angularly separated from the first irradiation line by a known angle. In some configurations, the irradiation lines are formed by the laser emitting light pulses (e.g., rapidly).

[0079]

[0085] In step 808, a scanning mirror is used to sweep the first and second illumination lines across the entire field of view. Objects in the field of view are illuminated by the first illumination line and then by the second illumination line with a known time delay.

[0080]

[0086] In step 812, reflections from objects in the field of view caused by the first and second illumination lines are detected by two or more detectors. For example, a first sub-image (e.g., a first 3D image as a first point cloud) is created by sweeping the first illumination line across the entire field of view and detecting reflections from objects, and a second sub-image (e.g., a second 3D image as a second point cloud) is created by sweeping the second illumination line across the entire field of view and detecting reflections.

[0081]

[0087] In step 816, a first distance to the object and / or the position of the object are calculated by detecting the reflection from the first illumination line, and a second distance to the object and / or the position of the object are calculated by detecting the reflection from the second illumination line.

[0082]

[0088] In step 820, the velocity of the object is calculated based on the difference between the first distance, the second distance, and the known time delay, or the difference between the first position, the second position, and the known time delay (as described, for example, in relation to Figures 4 and 5).

[0083]

[0089] In some configurations, the method further includes calculating the object's three-dimensional velocity vector by analyzing the change in the object's position between a first sub-image generated from first reflection data and a second sub-image generated from second reflection data.

[0084]

[0090] Various features described herein, such as methods, apparatus, computer-readable media, etc., can be implemented using combinations of dedicated components, programmable processors, and / or other programmable devices. Some processes described herein can be performed on the same processor or different processors. Where some components are described as being configured to perform a particular operation, such configuration can be achieved, for example, by designing electronic circuits to perform the operation, by programming programmable electronic circuits (such as microprocessors) to perform the operation, or by a combination thereof. Furthermore, while the embodiments described above may refer to specific hardware and software components, those skilled in the art will understand that different combinations of hardware and / or software components may be used, and certain operations described as being implemented in hardware may be implemented in software, and vice versa.

[0085]

[0091] The above description provides details to help understand the embodiments. However, it should be understood that embodiments may be carried out without some of the specific details. In some examples, well-known circuits, processes, algorithms, structures, and techniques are not shown in the figures.

[0086]

[0092] While the principles of this disclosure are described above in relation to specific apparatuses and methods, it should be understood that this description is provided only as an example and does not limit the scope of this disclosure. The embodiments are selected and described to illustrate the principles and practical applications, thereby enabling those skilled in the art to utilize this disclosure in various embodiments and modifications to suit their specific intended uses. It should be understood that the description is intended to encompass modifications and equivalents.

[0087]

[0093] Furthermore, it should be noted that embodiments may be described as processes shown as flowcharts, flow diagrams, data flow diagrams, structural diagrams, or block diagrams. While flowcharts may describe operation as a series of processes, many of these operations can be performed in parallel or simultaneously. Moreover, the order of operations may be rearranged. A process terminates when its operations are complete, but it may have additional steps not shown in the diagram. A process may correspond to a method, function, procedure, subroutine, subprogram, etc.

[0088]

[0094] The use of “a,” “an,” or “the” is intended to mean “one or more” unless otherwise indicated. All patents, patent applications, publications, and descriptions referenced herein are incorporated by reference in their entirety for all purposes. No prior art is recognized.

[0089]

[0095] Certain details of a particular embodiment may be combined in any suitable manner without departing from the spirit and scope of the embodiments of the present invention. However, other embodiments of the present invention may focus on specific embodiments relating to each individual aspect, or on specific combinations of these individual aspects.

[0090]

[0096] The above description of embodiments of this disclosure is presented for illustrative and explanatory purposes only. It is not intended to be exhaustive or to limit this disclosure to the exact forms described, and many modifications and variations are possible in light of the above teachings. These embodiments have been selected and described to illustrate the principles of the present invention and their practical applications, thereby enabling those skilled in the art to utilize the invention in various embodiments and modifications to suit specific intended uses. [Explanation of Symbols]

[0091] 100 Lida Sensor 110-a light source 110-b light source 120 light pulses 120' Collimated Light Pulse 122 Part of the light pulse 122' Part of the light pulse (return light pulse) 130 Illuminating Lens 140 light-receiving lens 150 Object 160-a detector 160-b Second detector 190 processors 200 Rider System 204 First Laser 208 Second laser 212 Scanning mirror 216 IR window 218 Pivot 220 Beam Splitter 224 First lens 228 First detector 230 Second lens 232 Second detector 240 processing units 304 First Field of View (FOV) 308 Second field of view (FOV) 312 Duplicate area 400 Rider System 404 Laser 404-1 First Laser 404-2 Second Laser 408 detectors 408-1 First detector 408-2 Second detector 412 Lens 412-1 First lens 412-2 Second lens

Claims

1. A system for detecting the velocity of an object using a lidar, A first laser configured to generate a first irradiation line within the field of view, A second laser configured to generate a second irradiation line within the field of view, The second irradiation line is angularly separated from the first irradiation line by a known angle. The aforementioned known angle is 1 to 15 degrees, and the second laser, A scanning mirror configured to sweep the first and second irradiation lines across the entire field of view, The object within the field of view is irradiated by the first irradiation line, and then irradiated by the second irradiation line after a known time delay. The known time delay is a function of the known angle and the angular velocity of the scanning mirror, A first detector configured to detect a first reflection of the first laser from the object, A second detector configured to detect a second reflection from the object by the second laser, A processing unit, The method involves generating a first sub-image of the object based on data detected from the reflection by the first laser, which includes detecting the first reflection, and the first sub-image being a first point cloud. The method involves generating a second sub-image of the object based on data detected from the reflection by the second laser, which includes detecting the second reflection, and the second sub-image being a second point cloud. A processing unit is configured to calculate the three-dimensional velocity vector of an object by analyzing the change in the object's position between the first sub-image and the second sub-image and the known time delay, A system that includes these features.

2. The first laser is part of the first laser array, and the second laser is part of the second laser array. The system according to claim 1, wherein the first laser array and the second laser array share a focusing lens.

3. The system according to claim 1, wherein the first laser array, the second laser array, the first detector, the second detector, and the processing unit are located on the same chip.

4. The system according to claim 1, wherein the scanning mirror is a vibrating mirror or a rotating polyhedron mirror.

5. A system for detecting the velocity of an object using a lidar, A first laser configured to generate a first irradiation line within the field of view, A second laser configured to generate a second irradiation line within the field of view, wherein the second irradiation line is angularly separated from the first irradiation line by a known angle, and the second laser A scanning mirror configured to sweep the first and second irradiation lines across the entire field of view, The object within the field of view is irradiated by the first irradiation line, and then irradiated by the second irradiation line after a known time delay. The known time delay is based on the known angle of the scanning mirror and A first detector configured to detect a first reflection of the first laser from the object, A second detector configured to detect a second reflection from the object by the second laser, A processing unit, Calculating the first position of the object based on detecting the first reflection, Calculating the second position of the object based on detecting the second reflection, A processing unit configured to calculate the velocity of the object based on the difference between the first position, the second position, and the known time delay, A system that includes these features.

6. The system according to claim 5, wherein the known angle is between 1 and 15 degrees.

7. The system according to claim 5, wherein the known time delay is a function of the known angle and the angular velocity of the scanning mirror.

8. The system according to claim 5, wherein the processing unit is further configured to calculate a three-dimensional velocity vector of the object by analyzing the change in the position of the object between a first sub-image generated from the first reflection data and a second sub-image generated from the second reflection data.

9. The system according to claim 5, wherein the first laser is part of a first laser array, and the second laser is part of a second laser array.

10. The system according to claim 9, wherein the first laser array and the second laser array share a focusing lens.

11. The system according to claim 9, wherein the first laser array, the second laser array, the first detector, the second detector, and the processing unit are located on the same chip.

12. The system according to claim 5, wherein the scanning mirror is a vibrating mirror or a rotating polyhedron mirror.

13. A method for detecting the velocity of an object using a lidar, comprising emitting light from a first laser configured to generate a first illumination line, Emitting light from a second laser configured to generate a second irradiation line, wherein the second irradiation line is angularly separated from the first irradiation line by a known angle. The sweeping method involves using a scanning mirror to sweep the first and second illumination lines across the entire field of view, wherein an object within the field of view is illuminated by the first illumination line and then by the second illumination line with a known time delay. Using at least one detector array, the reflection of the first irradiation line and the reflection of the second irradiation line from the object are detected, The first position of the object is calculated based on the reflection of the first irradiation line, The second position of the object is calculated based on the reflection of the second irradiation line, A method comprising calculating the velocity of an object based on the difference between the first position, the second position, and the known time delay.

14. The method according to claim 13, wherein the known angle is 1 to 15 degrees.

15. The method according to claim 13, wherein the known time delay is a function of the known angle and the angular velocity of the scanning mirror.

16. The method according to claim 13, further comprising calculating a three-dimensional velocity vector of the object by analyzing the change in the position of the object between a first sub-image generated from the first reflection data and a second sub-image generated from the second reflection data.

17. The method according to claim 13, wherein the first laser is part of a first laser array, and the second laser is part of a second laser array.

18. The method according to claim 17, wherein the first laser array and the second laser array share a focusing lens.

19. The method according to claim 17, wherein the first laser array, the second laser array, the first detector, the second detector, and the processing unit are located on the same chip.

20. The method according to claim 13, wherein the scanning mirror is a vibrating mirror or a rotating polyhedron mirror.

21. It is a system for riders, A first laser source configured to emit light of a first wavelength, A second laser source configured to emit light of a second wavelength different from a first wavelength, A scanning mirror, Scanning the light from the first laser source across the entire first field of view, Scanning the light from the second laser source across the entire second field of view, A scanning mirror configured to receive reflected light from the first field of view and the second field of view, A beam splitter arranged to receive the reflected light from the scanning mirror, the beam splitter configured to separate the reflected light into a first optical path corresponding to the first wavelength and a second optical path corresponding to the second wavelength, A first detector is placed in the first optical path and detects reflected light of the first wavelength, A second detector is placed in the second optical path and detects reflected light of the second wavelength, A system that includes these features.

22. A first lens having a first focal length is placed in the first optical path, The system according to claim 21, further comprising a second lens having a second focal length in the second optical path, wherein the second focal length is longer than the first focal length.

23. The first optical path is optimized for a first detection range and a first field of view. The second optical path is optimized for the second detection range and the second field of view. The second detection range is longer than the first detection range. The system according to claim 22, wherein the second field of view is narrower than the first field of view.

24. The system according to claim 21, wherein the first wavelength and the second wavelength are 850 nm to 960 nm.

25. The system according to claim 24, wherein the first wavelength is 905 nm plus or minus 10 nm, and the second wavelength is 940 nm plus or minus 10 nm.

26. The system according to claim 21, further comprising a processing unit configured to generate a three-dimensional point cloud by combining data from at least the first detector and the second detector.

27. A method for a lidar to detect nearby and distant objects, Emitting a first laser pulse within a first field of view, wherein the first laser pulse is characterized by a first wavelength. Emitting a second laser pulse within a second field of view, wherein the second laser pulse is characterized by a second wavelength. Receiving reflected light from the first field of view and the second field of view, The reflected light is separated into a first optical path corresponding to the first wavelength and a second optical path corresponding to the second wavelength. Using a first detector placed in the first optical path, the reflected light of the first wavelength is detected. The reflected light of the second wavelength is detected using a second detector placed in the second optical path, Based on the first detector which detects reflected light corresponding to the first wavelength, a first distance to the first object in the first field of view is calculated, A method comprising calculating a second distance to a second object in the second field of view based on a second detector that detects reflected light corresponding to the second wavelength.

28. The process involves passing light of the first wavelength through a first lens having a first focal length, wherein the first lens is located within the first optical path. The method according to claim 27, further comprising passing light of the second wavelength through a second lens having a second focal length, wherein the second lens is located in the second optical path.

29. A method for measuring distance using a lidar system, To emit a first laser pulse toward the first field of view, To emit a second laser pulse towards the second field of view, In response to detecting the reflection of the laser pulse from the first detector, the first time-of-flight measurement is initiated to calculate the first distance to the first object in the first field of view, After emitting the second laser pulse, and before detecting the reflection by the second laser pulse, the system waits for a predetermined time delay. A second time-of-flight measurement is initiated based on the reflection from the second laser pulse, A method comprising calculating a second distance to a second object in the second field of view based on the second time-of-flight measurement, wherein the second range is further from the LiDAR system than the first range.

30. The method according to claim 29, wherein the predetermined time delay corresponds to the round-trip propagation time of light to the minimum distance of the second field of view.

31. The method according to claim 30, wherein the minimum distance in the second range is 250 meters or more.

32. The method according to claim 29, wherein the first field of view and the second field of view overlap at least partially.

Images