Lidar systems and methods

Abstract

System (100; 200; 400; 500; 1000; 1200; 1400) for detecting light and measuring distance (LIDAR), wherein the system comprises the following: a light source (101; 101a-b) configured to produce a beam that is tunable over a range of frequencies; an optical beam steering device (102; 1700; 1725; 1750; 1775) positioned to receive at least one section of the beam and configured to sweep the beam over a range of angles in a field of view (FOV) (190), each discrete frequency of the beam corresponding to a different angle in the FOV (190); a detector (103; 103a-b) positioned to receive sections of the beam reflected by an object (191a-c; 622a, 622b) within the FOV (190) and configured to generate an interference signal (1501) based on the received sections of the beam; and a processor (181) that is communicatively coupled to the detector (103; 103ab), wherein the processor (181) is configured to: to cause the light source (101; 101a-b) to tune the beam from a first frequency to a second frequency; and to calculate an area of ​​an object (191a-c; 622a, 622b) corresponding to either the first frequency or the second frequency within the FOV (190), wherein the processor (181) for calculating the distance of the object (191a-c; 622a, 622b) is configured to segment the interference signal (1501) using a window function (1502), wherein the window function (1502) corresponds to a specific segment of the FOV (190).

Description

TECHNICAL AREA

[0001] The present application generally relates to the field of detection and, in particular, detection arrangements for the detection of light and for distance measurement (LIDAR). BACKGROUND

[0002] LiDAR systems use light to detect the distance between a light source and a target. A beam (e.g., a laser) is directed at the target. LiDAR systems typically identify the time it takes for the light to reach the target, be deflected by the target, and return to a detector. Based on this time and the speed of light, the distance to the target is determined. Target detection and the determination of target positions in three-dimensional space must be performed reliably, continuously, and in a timely manner for a machine (i.e., an autonomous vehicle) to operate safely.

[0003] US 2019 / 0317199A1 discloses a lidar detection system comprising a light source that is controlled to project a collimated beam at various wavelengths. An interferometer receives the collimated beam and projects an object beam corresponding to the collimated beam onto a diffraction grating. The object beam is diffracted at different angles at the grating, depending on the wavelength of the collimated beam, thereby generating a two-dimensional scan along a first axis. The object beam is additionally controlled along a second axis perpendicular to the first axis. This allows the lidar detection system to generate a horizontal and vertical scan (e.g., a three-dimensional scan) of the environment.

[0004] US 2018 / 0113200A1 describes a LiDAR system with a processor configured to control at least one light source so that the light intensity can vary over a scan of a field of view using light from the at least one light source, and to control at least one light deflector to deflect light from the at least one light source. Furthermore, the processor is configured to obtain an identification of at least one distinguishable area of ​​interest within the field of view and to increase the light allocation to the at least one distinguishable area of ​​interest compared to other areas, such that after an initial scan cycle, the light intensity in at least one subsequent second scan cycle at locations associated with the at least one distinguishable area of ​​interest is higher than the light intensity in the first scan cycle at locations associated with the at least one distinguishable area of ​​interest.

[0005] US 2020 / 0371239A1 discloses a lidar system that scans a beam in a complete 360° field of view without moving parts. The system comprises a transmitter subsystem with a tunable laser beam source, a laser beam-responding SPPR (Specific Photon Reflector), and a conical mirror that receives the output beam and directs it into the desired field of view. The system also includes a receiver subsystem that responds to a reflected beam from an object. The object receives the output beam emitted by the mirror, and the receiver subsystem comprises a plurality of detector modules, each containing a receiving detector, arranged such that at least one detector module receives the reflected beam from every direction.The system also includes a signal processor subsystem that tunes the frequency of the laser beam generated by the laser source to change the angular orientation of the output beam and to scan the output beam in the 360° field of view.

[0006] US 2007 / 0171367A1 describes the acquisition of positional information with respect to a face, and specifically an eyeball within a face, using a detection and distance measurement system, such as a radio detection and ranging (“RADAR”) system or a light detection and ranging (“LIDAR”) system. The positional information may include the location of the eyeball, translational motion information with respect to the eyeball (e.g., displacement, velocity, acceleration, jerk, etc.), and rotational motion information with respect to the eyeball (e.g., angle of rotation, rotational velocity, rotational acceleration, etc.) during the rotation of the eyeball within its orbit.

[0007] US 2008 / 0063028A1 discloses a wireless communication method that includes selecting a photonic signal to generate a carrier frequency for wireless communication. In an exemplary case, the selected photonic signal may have sidebands with a frequency difference corresponding to a carrier frequency within one of several predetermined carrier frequency bands. In some embodiments, each of the predetermined carrier frequency bands may exhibit a local minimum with respect to signal attenuation over a wireless communication signal path. For example, the selection of the photonic signal may be based on predetermined selection criteria, such as error information and / or signal path conditions (e.g., atmospheric humidity, noise level, signal strength). Devices for carrying out such methods may include a wireless communication system with a transmitter and / or receiver.

[0008] US 2003 / 0080899A1 relates to a phased-array antenna in which a gain-modulated, multimode Fabry-Perot laser diode (FP-LD) is used in combination with highly dispersive fiber. The invention relates in particular to techniques that enable a compact and cost-effective system implementation of an optically controlled phased-array antenna. Furthermore, it allows for a continuous time delay for each antenna element in the array in order to selectively generate phase differences. SUMMARY

[0009] The present technology provides systems and methods for LIDAR that are capable of detecting, tracking, and determining the speed of an object within a field of view (FOV).

[0010] The invention relates to systems and methods for detecting light and measuring distance (LIDAR) according to the independent claims. Advantageous embodiments are disclosed in the dependent claims.

[0011] The preceding summary is for illustrative purposes only and is not intended to be limiting in any way. In addition to the illustrative aspects and features described above, further aspects and features will become clear through reference to the following drawings and the detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The foregoing and other features of the present disclosure will become more apparent from the following description and the attached claims in conjunction with the attached drawings. Since these drawings only show some implementations in accordance with the disclosure and are therefore not to be considered as limiting the scope of the disclosure, the disclosure is described with additional specificity and detail using the attached drawings. Fig. Figure 1 shows a block diagram of a LIDAR system in accordance with an illustrative embodiment. Fig. Figure 2 represents a first example of a LIDAR system in accordance with an illustrative embodiment. Fig. Figures 3a-3b represent examples of detection scans of a LIDAR system in accordance with an illustrative embodiment. Fig. Figure 4 presents a second example of a LIDAR system in accordance with an illustrative embodiment. Fig. Figure 5 represents a third example of a LIDAR system in accordance with an illustrative embodiment. Fig. 6a and Fig. 6b presents further examples of detection scans of a LIDAR system in accordance with an illustrative embodiment. Fig. Figure 7 shows a diagram of a signal profile of a light source in accordance with an illustrative embodiment. Fig. 8a and Fig. Figure 8b presents examples of variable density scans of a LIDAR system in accordance with an illustrative embodiment. Fig. 9a and Fig. Figure 9b presents examples of two-dimensional scans of the external environment in accordance with an illustrative embodiment. Fig. Figure 10 presents an example of a LIDAR system that has a 1xN divider in accordance with an illustrative embodiment. Fig. Figures 11a-11c provide examples of different detection scans that use a LIDAR system in accordance with one embodiment. Fig. Figure 12 presents a second example of a LIDAR that has a 1xN divider in accordance with an illustrative embodiment. Fig. Figure 13 presents an example of a detection scan using the LIDAR system. Fig. 12 in accordance with an illustrative embodiment. Fig. Figure 14a presents an example of rescanning using a reference interferometer in accordance with an illustrative embodiment. Fig. Figure 14b presents an example of segmentation of an interference signal collected by the detector using the reference signal from the reference interferometer in accordance with an illustrative embodiment. Fig. Figure 15 presents an example of signal segmentation using window functions in accordance with an illustrative embodiment. Fig. Figure 16 presents an example of generating LIDAR data from FFT data in accordance with an illustrative embodiment. Fig. 17a-e provide examples of LIDAR scanning using a beam scanner in accordance with an illustrative embodiment. Fig. Figures 18a-b show examples of the LiDAR scans using the beam guidance devices of the Fig. 17a-e in accordance with an illustrative embodiment. Fig. Figure 19 presents examples of LIDAR scanning using a micro-electromechanical (MEMS) scanner in accordance with an illustrative embodiment. Fig. Figure 20 presents an example of zero-padding to increase the number of FFT bins in accordance with an illustrative embodiment. DETAILED DESCRIPTION

[0013] The following detailed description refers to the accompanying drawings, which form a part thereof. In the drawings, similar symbols typically denote similar components unless the context specifies otherwise. The implementations illustrated in the detailed description, the drawings, and the claims are not to be understood as limiting. Other implementations may be used and other modifications made without departing from the spirit or scope of the subject matter presented here. It is understood that the aspects of the present revelation, as generally described herein and illustrated in the figures, may be arranged, substituted, combined, and designed in a multitude of different configurations, all of which are expressly considered and are part of this revelation.

[0014] This document describes systems and methods for lidar detection. As further explained below, a lidar detection system is disclosed herein, which includes a light source that is controlled to project a beam (e.g., an infrared beam, a beam, a collimated beam, etc.) with different wavelengths. The beam is directed onto a wavelength-dispersive element. The beam is projected by one or more wavelength-dispersive elements at an angle corresponding to the wavelength of the beam. As a result of changing the wavelength of the beam, the lidar detection system generates a scan along a first axis (e.g., a two-dimensional scan) of a field of view (FOV) of the external environment.A beam steering device can be used to allow the LiDAR detection system to create multiple vertical scans along a horizontal axis (or vice versa) to generate a three-dimensional scan of the LiDAR detection system's field of view (FOV). In some embodiments, the three-dimensional FOV scan is achieved using only static elements (e.g., the first and second wavelength-dispersive elements are both static). Various arrangements and techniques described herein allow for the measurement, segmentation, and near-real-time computation of a three-dimensional space around the LiDAR system, enabling the further development of the electronics. This allows the LiDAR system to be used in applications requiring precise object tracking (e.g., an autonomous vehicle).

[0015] Referring to Fig. Figure 1 shows a block diagram of a LiDAR detection system 100. The LiDAR detection system 100 includes a light source 101, an optical beam guide 102, and a detector 103. The LiDAR detection system 100 projects one or more beams generated by the light source 101 into the external environment within a field of view (FOV) 190 to detect, determine the distance to, and / or track one or more objects 191a-c (e.g., targets) within the FOV 190. In some embodiments, the LiDAR detection system 100 also includes a control circuit 180, which comprises a processor and memory, and which is coupled to the light source 101, the optical beam guide 102, and / or the detector 103. The memory may contain computer-readable instructions which, when executed by the processor, cause the operations of the LIDAR detection system 100 described herein.

[0016] The light source 101 is configured to emit or project a beam toward the optical beam-guiding device 102. In some embodiments, the beam (e.g., a laser beam) has a selectable, discrete frequency. Additionally, the light source 101 is configured to tune a wavelength λ (e.g., and thus the frequency) of the beam. That is, in some embodiments, the light source 101 can be a tunable laser in which the wavelength λ of the laser is tuned or selected. The light source 101 can be configured to set the wavelength λ of the beam within a specific range. In some examples, the range of wavelengths λ can be between 1.25 µm and 1.35 µm. The light source 101 can be swept over the range of wavelengths λ, as explained in more detail below.In some embodiments, the light source 101 can be continuously swept across the range of wavelengths from a first wavelength (and thus a first frequency) to a last wavelength (and thus a last frequency). The light source 101 can be continuously swept from the first wavelength to the last wavelength in a linear or nonlinear pattern. In some embodiments, the light source 101 can include one or more tunable lasers cascaded together so that the light source 101 has a wider range of wavelengths λ.

[0017] The optical beam-guiding device 102 is arranged to receive the beam (e.g., at least a segment of the beam) from the light source 101 and to project the beam into the external environment within the entire field of view (FOV) 190, directing reflected segments of the beam (e.g., from targets 191a-c) back to a detector 103. That is, the light source 101 is arranged to project components of a beam onto the optical beam-guiding device 102. The optical beam-guiding device 102 receives the beam and directs segments of the beam into the FOV 190. The segments of the beam are reflected by the objects 191a-c within the FOV 190, and at least one segment of the reflected beam is received again by the optical beam-guiding device 102. The optical beam steering device 102 receives the section of the reflected beam and directs the section of the reflected beam onto the detector 103.The detector 103 receives the segments of the reflected rays and generates an electrical signal that is characteristic of the received segments of the reflected light and thus of the object. The electrical signal can be transmitted to a processor of the control circuit 180, which can process the electrical signal (e.g., an object signal) to determine the distance and / or velocity of the objects 191a-c in the field of view 190.

[0018] In some embodiments, the optical beam-guiding device 102 can include one or more wavelength-dispersive elements configured to project the beam at an angle based on the beam's frequency. For example, in some embodiments, the field of view (FOV) 190 can be defined along a first angle θ by the extrema of the frequencies of the beam projected by the light source 101. In this way, in some embodiments, the optical beam-guiding device 102 can be configured to disperse a light beam along the first angle θ of the FOV 190 based on the properties (e.g., wavelengths) of the light beams.

[0019] In some embodiments, the optical beam-guiding device 102 can employ various techniques or devices to scan along a second angle φ of the external environment, as described in more detail below. The extrema of the second angle φ can define the FOV 190 along the second angle, thereby creating a three-dimensional FOV 190. In this way, in some embodiments, the optical beam-guiding device 102 can be configured to disperse a light beam along the first and second angles to scan the external environment.

[0020] The detector 103 is configured and positioned within the system to receive portions of the light reflected by objects within the field of view (FOV) 190. In some embodiments, the detector 103 is positioned to receive both the portions of the light reflected by the objects within the FOV 190 and a portion of the beam (e.g., the reference beam) to generate an interference signal. In some embodiments, the detector 103 may be communicatively coupled to the control circuit 180 (e.g., the processor). In some embodiments, the detector 103 includes an infrared sensor, a camera, an infrared camera, or another light-detection device capable of detecting the frequency of the received light. The detector 103 is positioned such that the light received at the optical beam-guiding device 102 (e.g., the light reflected by objects 191a-c) can be directed onto the detector 103.For example, in some embodiments, the LIDAR system 100 can include various optical elements such as half-mirrors, reciprocal mirrors, semi-mirrored mirrors, or other optical elements configured to direct light from the light source 101 toward the optical beam guider 102 and light from the optical beam guider 102 toward the detector 103. The detector 103 is configured to generate an object signal indicating the sections of the beam that are detected by the detector 109. In some embodiments, the object signal is in the form of an electrical signal and is transmitted to the computing system 112 for processing.

[0021] The control circuit 180 includes a processor 181 and a memory 182. The processor 181 can include any component or group of components configured to execute, implement, and / or perform any of the processes or functions described herein, or any form of instructions to execute or cause such processes to be executed. In one or more arrangements, the processor 181 can be a main processor of the LIDAR detection system 100. Examples of suitable processors include microprocessors, microcontrollers, DSP processors, and other circuits capable of executing software.Other examples of suitable processors include, but are not limited to, a central processing unit (CPU), an array processor, a vector processor, a digital signal processor (DSP), a field-programmable gate array (FPGA), a programmable logic array (PLA), an application-specific integrated circuit (ASIC), programmable logic circuits, and a controller. Processor 181 can include at least one hardware circuit (e.g., an integrated circuit) configured to execute instructions contained in the program code. In arrangements containing multiple processors, these processors can operate independently, or one or more processors can operate in combination.

[0022] The memory 182 can be structured to store one or more types of data. The memory 182 can include volatile and / or non-volatile memory. Examples of suitable memory 182 include RAM (Random Access Memory), Flash Memory, ROM (Read Only Memory), PROM (Programmable Read-Only Memory), EPROM (Erasable Programmable Read-Only Memory), EEPROM (Electrically Erasable Programmable Read-Only Memory), registers, magnetic disks, optical disks, hard disks, or any other suitable storage medium or combination thereof. In some embodiments, the memory 182 includes a non-transient, computer-readable storage medium that is communicatively coupled to the processor 181.The computer-readable storage medium may contain encoded or otherwise stored instructions which, when executed by the processor, cause the processor to perform one of the operations, steps, or procedures described herein. Memory 182 may be a component of the processor 181, or memory 182 may be operationally connected to the processor 181 for use by it. In some arrangements, memory 182 may be located at a remote location and be accessible to the processor 181, for example, by means of a suitable communication device.

[0023] The processor 181 is communicatively coupled to the light source 101 and can be configured to read and execute instructions from a light source controller stored or programmed in memory 182. The light source controller can consist of or include computer-readable instructions to control one or more aspects of the light source 101. The light source controller can be stored in memory 182, as shown. In other implementations, the light source controller 182 can be stored decentrally and be accessible to various components of the lidar detection system 100. The processor 181 can control the light source 101 in accordance with the instructions of the light source controller 118.

[0024] The light source control can include instructions for generating a pattern for the beam projected by the light source 101. For example, in some implementations, the beam from the light source 101 can be projected in a pattern that has a frequency (e.g., pulsed, sawtooth, etc.). The light source control can include instructions to generate, for example, a sawtooth signal that corresponds to the frequency pattern of the beam projected by the light source 101. In some embodiments, the light source control 118 can include instructions that cause the light source 101 to generate a beam that sweeps from a first frequency at a first time to a second frequency over an upward ramp time interval and from the second frequency back to the first frequency over a downward ramp time interval.In some embodiments, the light source control can include instructions that cause the light source to generate one or more frames. In some embodiments, the multiple frames are periodic and have a specific time interval between each frame. As explained further below, the frequency pattern of a frame can be used to determine the distance and / or speed of an object.

[0025] In some embodiments, one or more components of the LIDAR system 100 can be omitted. In some embodiments, various other components of the LIDAR system 100 can be included. It is to be understood that Fig. 1 is an example of an implementation of a LIDAR system 100 and that it is not intended to be restrictive.

[0026] For example, in some embodiments, the LIDAR system 100 can include an interferometer. The interferometer can consist of, or include, components arranged to receive the beam from the light source 101 and split the beam into one or more partial beams. For example, the interferometer can split the beam into an object beam and a reference beam. The object beam can be projected toward the wavelength-dispersive element 104, and the reference beam can be projected toward a reference mirror. The interferometer can generate an interference pattern based on the difference between the light reflected from the surfaces of the objects 191a-c in the external environment and the light reflected from the reference mirror. The LIDAR detection system 100 (e.g., the processor 181) can determine a distance to the objects based on the interference pattern (e.g., the interference signal).

[0027] Now, referring to Fig. Figure 2 shows an example of a LIDAR system 200. When discussing Fig. 2 is applied to various components of for demonstration purposes. Fig. 1. Referenced. In Fig. Figure 2 of the LIDAR system 200 includes multiple light sources 101a-b and multiple detectors 103a-b. In this example, each light source 101a-b has a corresponding detector 103a-b. In this arrangement, an array of N light sources 101a-b can be used to scan the external environment along the second angle.

[0028] The light sources 101a-b can include tunable lasers configured to project a beam across a variety of frequencies, for example, from a first frequency to a last frequency. Each of the light sources 101a-b is arranged to project a specific beam toward a wavelength-dispersive element 220. The respective beams strike the wavelength-dispersive element at different locations, allowing them to be projected into the external environment along the second angle. As described above, the wavelength-dispersive element 220 projects the respective beams into the external environment along the first angle, depending on the beam frequency. In some embodiments, each of the light sources 101a-b can have different bandwidths (e.g., frequency ranges).The different or controlled bandwidths of the individual light sources 101a-b allow different areas of angles along the first angle to be scanned at different angles along the second angle, allowing the field of view to take on 190 different shapes.

[0029] In Fig. In the second part of the document, each of the light sources 101a-b is paired with a corresponding detector 103a-b, which is arranged to receive segments of a corresponding beam from the external environment. This advantageously allows each of the paired light sources 101a-b and the respective detectors 103a-b to perform a scan of the external environment simultaneously. In this way, an entire three-dimensional scan of the FOV 190 can be performed simultaneously or nearly simultaneously, thereby reducing the time required by the LIDAR system 200 to generate a three-dimensional scan of the external environment.

[0030] In one embodiment, a first of the light sources 101a projects a first beam toward a first optical element 211. The first beam is further projected onto a second optical element 212, which aligns the first beam with a first section of a third optical element 213. The third optical element 213 then directs (e.g., by refraction or reflection) the first beam onto a first section of the wavelength-dispersive element 220. The first beam is dispersed into the external environment according to the beam's frequency, and the light reflected by objects in the external environment is reflected back to the first optical element 211 along the same path by which the first beam left the LIDAR system 200. The reflected beam is then directed to a fourth optical element 214 and to a first detector 214. Similarly, a second light source 101b (e.g.,The Nth light source directs a second beam to a fifth optical element 215 and to a sixth optical element 216, which directs the second beam onto a second section of the third optical element 213. The third optical element 213 then directs (e.g., by refraction or reflection) the first beam onto a second section of the wavelength-dispersive element 220, which disperses the second beam into the external environment. Sections of the second beam can be reflected by objects in the external environment and directed back to a second detector 103b (e.g., the Nth detector) via a seventh optical element 217. In other embodiments, other arrangements or optical elements can be used for paired scanning. In some embodiments, the LIDAR system 200 can include two, three, four, five, or a number N of light sources 101a-b paired with corresponding detectors.In this example, the paired light sources 101a-b with the corresponding detectors 103a-b enable the coaxial detection of objects within the FOV 190. In alternative embodiments, a separate detector array can be used to receive the reflected beams for off-axis detection. For example, an off-axis detector or a detector array can be positioned or arranged to receive the reflected beams directly or via optical elements such as lenses, mirrors, etc.

[0031] Now, referring to the Fig. Figures 3a-b show examples of detection scans from the LIDAR System 200. Fig. Figure 3a represents a signal diagram 300 for a first beam of the LIDAR system 200. Fig. Figure 3b represents a multi-beam scan 350 of the LIDAR system 200. The signal diagram 300 includes a y-axis representing the bandwidth or frequency range Δf. mirepresents, for example, a set frequency f. oi the first light source 101a is offset, and an x-axis representing the time for the tuning period t mi For example, the first light source 101a is represented by a sweep of frequencies. The signal diagram 300 includes a reference signal 301, which indicates the sweep of frequencies, for example by the first light source 101a, a first reflected signal 302, which indicates a first object A0, and a second reflected signal 303, which indicates a second object A1. The control circuit 180 can calculate the position of the first and second objects relative to the LIDAR system 200 based on a beat frequency of the first and second signals, respectively.

[0032] Now, referring to Fig. 3b The multi-beam scan 350 includes a y-axis representing the light sources 101a-b and an x-axis representing the first angle θ. For example, the multi-beam scan 350 is a representation of the FOV 190, where the y-axis of the FOV 190 is based on the light source arrangement of the LIDAR system 200 and the x-axis is based on the frequency of the beam. For example, the LIDAR system 200 can perform a first scan of the entire FOV 190 at a first time. The first scan can indicate to the control circuit 180 that an object is located near (e.g., within a predefined area) the LIDAR system 200. Accordingly, the control circuit 180 can determine whether the object should be closely monitored or segmented for further analysis. In this case, the control circuit 180 determines which light sources 101a-b should be activated (e.g., painted) for the segmentation of the object.In subsequent cycles, the control circuit 180 can, for example, select a specific light source from among the multiple light sources 101a-b starting from a set frequency f. oi over a range of frequencies Δf specific to the object mi Swipe to scan within the area of ​​the detected object. For example, it could be in Fig. 3b. If the detected object is a car within a predefined area, the control circuit 180 can determine that a fifth and sixth light source should be swept at the set frequency across a calculated range of frequencies to monitor, segment, and / or dissect the detected car at different positions along the y-axis. Furthermore, the control circuit 180 can perform sweeping or scanning across the maximum range of frequencies using other light sources (e.g., the first light source 101a) to search for other objects that might appear within the field of view (FOV) 190. In this way, the control circuit 180 can dynamically and effectively increase the speed of the external environment scan, thereby enhancing the efficiency of the LiDAR system 200.

[0033] Now, referring to Fig. Figure 4 shows another example of a LIDAR 400 system. For illustrative purposes, when discussing Fig. 4 on different components of Fig. 1. Referenced. The LIDAR system 400 includes several (e.g., an N quantity) wavelength-dispersive elements 420a-b with an optical element 421 configured to project a beam from the light source 101a onto the wavelength-dispersive elements 420a-b. The several wavelength-dispersive elements 420a-b are positioned such that different segments of the beam are dispersed along the second angle φ of the external environment. The different frequency or tuning of the beam allows scans along the first angle θ of the external environment. In this arrangement, an entire scan of the FOV 190 can be achieved by a single frequency scan or sweep from the light source 101.

[0034] Now, referring to Fig. Figure 5 shows another example of a LIDAR system 500. The LIDAR system 500 includes a wavelength-dispersive element 520 with several optical elements 522a-b (e.g., mirrors) and a second optical element 521 (e.g., a lens). The several optical elements 522a-b are positioned to direct respective segments of a beam from the light source 101 through the second optical element 521 and onto the respective segments of the wavelength-dispersive element 520. The arrangement and structure of the several optical elements 522a-b (e.g., mirrors) and the second optical element 521 (e.g., the lens) allow different segments of the beam to be projected onto the respective segments of the wavelength-dispersive element 520 and thereby dispersed along the second angle φ of the external environment. The different frequency or tuning of the beam allows scans along the first angle θ of the external environment.In this arrangement, an entire scan of the FOV 190 can be achieved by a single frequency scan or by sweeping from the light source 101.

[0035] Now, referring to the Fig. 4 and Fig. 5. The LIDAR systems 400 and 500 include an array of detectors 103a-103b. In some embodiments, the number of detectors in the array can be the same as the number of wavelength-dispersive elements 420a-b or the multiple optical elements 522a-b (e.g., mirrors). In one example, the light source 101 projects a beam toward a first element 490. The beam can pass through the first element 490 and be directed toward a second element 491 (e.g., a collimated lens). From the second element 491, the beam is directed either onto the multiple wavelength-dispersive elements 420a-b, as in Fig. 4 shown, or on the wavelength-dispersive element 520, as in Fig. Figure 5 shows the beam and projects it into the external environment. Sections of the beam are reflected by objects in the field of view (FOV) 190 back towards the first element 490, which directs (e.g., reflects or refracts) the beam sections towards a respective detector 103a-b. In some embodiments, the respective beam sections are directed by the first element 490 towards the respective optical element 403a-b, which then directs the beam sections towards the respective detector 103a-b.

[0036] Now, referring to the Fig. 6a and Fig. Figure 6b shows an example of a detection scan. Fig. Figure 6a represents a two-dimensional scan 600 using frequency tuning. Fig. Figure 6b represents a corresponding signal diagram 650 of the two-dimensional scan. The two-dimensional scan 600 includes a wavelength-dispersive element 620 that disperses a beam 690 into an external environment at an angle dependent on the beam's frequency. In this example, the external environment includes a first object 622a and a second object 622b. The first object is located at a first distance R0 from the wavelength-dispersive element 620, and the second object is located at a second distance R1 from the wavelength-dispersive element 620. During a two-dimensional scan, the beam 690 is directed towards the first object 622a over a first range of frequencies and towards the second object 622b over a second range of frequencies.

[0037] The signal diagram 650 includes a first signal 651, which represents a frequency of the beam relative to time (e.g., the frequency sweep of the beam). The signal diagram 650 also includes a second signal 652, which represents a detected portion of the beam reflected back from the first object 622a to a detector when the first distance R0 is less than a maximum distance R MAX is, and a third signal 653, representing a detected section of the beam reflected back to the detector from the second object 622b. Also included is a fourth signal 654, representing a detected section of the beam reflected back to a detector from the first object 622a when the first distance R0 is greater than the maximum distance R. MAX The maximum distance can be calculated by multiplying the speed of light by a time period t. d be divided by two.

[0038] In one embodiment, the control circuit 180 can use a low-pass or a band-pass filter to limit the detection range R. det to limit the frequency so that the beat frequency of an object is simple at each increment and can be counted by a frequency counter. In this way, a beat frequency higher than a maximum beat frequency is filtered out, thereby improving the accuracy of object detection for objects that are less than the maximum distance away using the frequency counter. In some embodiments, the cutoff frequency of the filter can be determined based on the time interval t. d Specific segmentation of the FOV can be dynamically set.

[0039] In one embodiment, the control circuit 180 can perform an FFT analysis with an analog-to-digital converter (ADC) to detect or identify objects at positions greater than the maximum distance R. MAX As shown above, light emanating from an object at a distance greater than the maximum distance R can MAXThe reflected light is detected by a detector of the system via the same optical path, including the wavelength-dispersive element 620. However, due to multiple light signals in a segment or period (e.g., the third and fourth signals 653 and 654), the light is not correctly detected by a frequency counter. In one embodiment, however, the control circuit 180 can utilize an ADC circuit to detect multiple reflected object signals in a segment or period and calculate the positions of all objects with respect to the reflected object signals. For example, multiple peaks in the FFT signals can be detected, and the corresponding distances for each peak can be identified based on the peak positions in the FFT.

[0040] Referring to Fig. Figure 7 shows a signal diagram 700 of a light source 101. In some embodiments, the light source 101 can include multiple tunable lasers cascaded together. In some embodiments, each of the multiple tunable lasers can have different sweep rates and / or bandwidths. The beams of the individual tunable lasers can be coupled into a single path to function as the light source 101. For example, the signal diagram 700 shows a first beam 701 from a first tunable laser L1, a second beam 702 from a second tunable laser L2, and a third beam 703 from a third tunable laser L3. In some embodiments, each tunable laser can cover the frequency sweep range over different segments M1. For example, the first beam 701 covers a first segment A1, the second beam 702 covers a second segment A2, and the third beam 703 covers three segments A1 and A2. 3-5Furthermore, any tunable laser L i different tuning ranges Δλ Li and corresponding time periods t Liwith varying sweep rates. In some embodiments, the entire sweep can be performed continuously or discretely using multiple tunable lasers. In some embodiments, there may be a gap between adjacent segments (e.g., A1 and A2) or an overlap between adjacent segments. The use of multiple tunable lasers ensures that a scan can be achieved across the maximum possible frequencies and thus the respective extremes of the angles in the external environment. Furthermore, the different sweep rates, bandwidths, and overlaps of the tunable lasers allow the LIDAR system to recognize specific patterns in the external environment, which can be selected based on the specific registration of the LIDAR system. This can improve object detection or resolution in important areas (e.g., areas of interest) of the FOV, as described in the following. Fig. 8a and Fig. 8b described.

[0041] Fig. 8a and Fig. Figure 8b provides an example of variable density scanning. Fig. Figure 8a shows an example of a two-dimensional scan 800 of the external environment. Fig. Figure 8b presents an example of a frequency sweep 850 of the light source for the two-dimensional scan. A first time interval t1 of the scan corresponds to a first segment A1 of the external environment, a second time interval t2 of the scan corresponds to a second segment A2 of the external environment, and a third time interval t3 corresponds to a third segment A3 of the external environment. In one embodiment, each segment A i the same time period t i and the same frequency bandwidth Δλ i exhibit. In some embodiments, the depth or length resolution can be determined by the bandwidth Δλ. i The resolution is proportional to λ. 2 / Δλ ior the wavelength divided by the frequency bandwidth of the respective tunable laser. For example, each time period t i on a segment A i be variable, so that every scan angle range Δθ i It can be variable. Accordingly, the density or resolution of the scan can be controlled by the control circuit 180.

[0042] Fig. 9a and Fig. Section 9b presents examples of three-dimensional scans of the external environment. As in relation to the Fig. 8a and Fig. As explained in section 8b, the scans of the external environment can be segmented. Accordingly, the control circuit 180 can increase the density of the segments around a region of interest (ROI). The segmentation and / or the ROI can be determined after an initial sweep or scan 900 of the FOV at constant density. In some embodiments, the segmentation and / or the ROI can be determined based on information from other sensors such as cameras or radar sensors. In some embodiments, the ROI or segmentation can be based on the detection of an object within a predefined area. After determining the ROI, the LiDAR system can determine a specific segmentation and perform further sweeps with the determined segmentation 950.In some embodiments, the LiDAR system can dynamically adjust the segmentation with each swipe or scan, based on a predefined set of rules that define what or where the ROI lies based on the sensor data. That is, in some embodiments, the segmentation can be varied with each frame (e.g., when scanning the FOV). In some embodiments, a different segmentation can be applied to the same frame (e.g., data from a single scan) if the frame is analyzed multiple times.

[0043] Fig. Figure 10 represents an example of a LIDAR system 1000 comprising a 1xN splitter 1010. The LIDAR system 1000 includes a light source 101 arranged to project a beam into the input of the 1xN splitter 1010. In one embodiment, the beam is directed onto a first optical element 1001, a second optical element 1002, a third optical element 1003, and into the input of the 1xN splitter 1010. In some embodiments, the 1xN splitter is coupled to and controlled by the control circuit 180. For example, the control circuit 180 can determine which of the N outputs an input beam is directed to. The beam is directed from one of the N outputs and directed by a fourth optical element 1021 onto a wavelength-dispersive element 1020, which disperses the beam into the external environment.In this arrangement, the N number of outputs each direct light onto a corresponding section of the wavelength-dispersive element 1020 at a corresponding angle of incidence, allowing the LIDAR system 1000 to perform scans at the second angle φ. Reflected sections of the beam 1090 can be directed back to the second optical element 1002 and then to a fifth optical element 1005. The fifth optical element 1005 can direct the reflected sections of the beam onto a sixth optical element 1006, which is configured to combine the reflected section of the beam 1090 with a reference section of the beam 1091 and direct the combined beams onto the detector 103.

[0044] In some embodiments, each path from the input to the respective N outputs of the 1xN splitter 1010 can have a different optical delay. Accordingly, the beam from the light source 101 can be projected onto the 1xN splitter and output at each of the N outputs via a scan or sweep. Each signal for each beam emitted from the respective N outputs can be distinguished by a single detector 103 due to the respective optical delays. The 1xN splitter is structured such that each path from the input to the respective N outputs includes an optical delay (e.g., spacing) that differs from the other paths (e.g., and is sufficiently large relative to the frequency scan time). In some embodiments, the optical frequency of the beam from the light source 101 can be scanned at once across the entire scan range along the first angle θ.Alternatively or additionally, the optical frequency of the beam can be sampled in segments to obtain the signals from all N beams in the respective segments. In this example, the tuning range can be the same for each segment width, but the offset optical frequency for each segment is different to steer the beam along the first axis to generate a scan across the entire scan area.

[0045] Referring to the Fig. Figures 11a-11c show examples of different detection scans. Fig. Figure 11a shows an example of a signal diagram 1100 of the LIDAR system 1000, which is continuously scanned along the first angle θ over the entire scan area. Fig. Figures 11b-11c represent an example of the beam being scanned along the first angle θ in each segment. In some embodiments, the tuning range or frequency change can be the same for each segment. For example, in the Fig. 11b-11c the offset frequency is set at each segment based on the segment to be measured, and a scan is performed over a subset of frequencies to measure each segment along the first angle θ.

[0046] Generally referring to Fig. Figure 11a includes the signal diagram 1100, which shows a representation of a first ray (e.g., ray 1) corresponding to the first path of the N paths of the 1xN divider 1010, a second ray (e.g., ray 2) corresponding to the second path of the N paths of the 1xN divider 1010, and an N-ray (ray N) corresponding to the last of the N paths. In this example, the ray from light source 101 was continuously swept across the entire range of frequencies, from the first to the last extreme value. As can be seen, the optical delay 2L allows i The function / c of ​​each ray allows processor 181 to determine which beat signals correspond to each ray and enables the processor to calculate the position of objects within the FOV. Processor 181 can then calculate, for each segment and each ray, the distances or ranges of targets corresponding to the beat signals or reflected signals by applying the equations R1, R2, R Nused.

[0047] Generally referring to Fig. Figure 11b includes a first signal diagram 1150, representing a first ray (e.g., ray 1) corresponding to the first path of the N paths of the 1xN divider 1010 during the first segment A0, a second ray (e.g., ray 2) corresponding to the second path of the N paths of the 1xN divider 1010 during the first segment A0, and an N-ray (ray N) corresponding to the last of the N paths during the first segment A0. In this example, the ray from the light source 101 was continuously swept from an offset frequency corresponding to the beginning of the first segment to a final frequency corresponding to the last frequency of the first segment. As can be seen, the optical delay 2L allows i / c of ​​each beam to determine for processor 181 which beat signals correspond to each beam, and allows the processor to calculate the position of objects within the FOV. In particular, when the delays L i are smaller than the delay of the adjacent path and 2 * (L i+1 - L i ) divided by the speed of light is greater than the time t d For segment sweeping, each beam can be emitted at a different time without overlap, ensuring that there are no overlapping object or beat signals. Processor 181 can then calculate the distances or range of a target for each segment and each beam using equations R1, R2, R N calculate.

[0048] Generally referring to Fig. Figure 11c shows a second signal diagram 1175, a signal of a first beam (e.g., beam 1) over several different segments A0, A1, A M , while the processor scans 181 segments one by one. The duration t k for each segment A i is equal to or longer than the frequency scan time for all beams N. That is, t k > 2 * ((L N - L1) / c) + t d Furthermore, the i-th frequency scan begins for segment A. i at a frequency of f si =f s0 + i * Δf d. In this way, the beam can be directed continuously without gaps over the first angle θ of the outer environment.

[0049] Referring to Fig. Figure 12 shows an example of a LIDAR system 1200 that includes a 1xN beam splitter 1210. The LIDAR system 1200 can be similar to the LIDAR system 1000. However, the LIDAR system 1200 includes several wavelength-dispersive elements 1251a-d, each of which is positioned to receive an output beam from a corresponding output of the 1xN beam splitter. In this way, the LIDAR system 1200 can be steered along the first angle θ of the external environment by wavelength tuning of the beam and along the second angle φ of the external environment by controlling the phase of the light reaching the respective wavelength-dispersive element 1251a-d (e.g., an optical phase array). This means that each path of the 1xN divider can include or act as a phase shifter, such as those used for optical phase arrays.The distance or separation of the objects at each beam emission angle can be calculated during wavelength tuning to generate a three-dimensional image of the FOV.

[0050] In a first example 1281, the optical phase array (OPA) is steered along the slow axis. In this example, wavelength tuning is performed over predefined M segments for N times to achieve two-dimensional beam steering. The beam is steered by the OPA along the slow axis at N discrete points, using N wavelength-dispersive elements 1251a-d.

[0051] In a second example 1282, the OPA is steered along the fast axis. That is, in various embodiments, a two-dimensional scan of the environment (e.g., FOV) can be achieved by multiple beam samples along the fast axis during a single beam scan along the slow axis. In the first example 1281, the second angle φ corresponds to the slow axis. In the second example 1282, the second angle corresponds to the fast axis. In this example 1282, the beam is steered during each segment A. i The beam is deflected at N discrete points by OPA along the second angle φ, and the beam is also deflected along the first angle θ depending on the wavelength. In this example, the two-dimensional beam deflection can be performed during a single beam tuning operation.

[0052] Referring to Fig. Figure 13 shows an example of a detection scan 1200 using the LIDAR system 1200. In this example, the beam is directed along both the first angle θ and the second angle φ using wavelength tuning. The phase difference between the beams at adjacent wavelength-dispersive elements 1251a-d can be determined by the optical path delay. The phase of each path for the respective 1xN splitter paths is given by Equation 1: Ψ=ΔL*2πn(λ) / λ In equation (1), λ is the beam wavelength and n is the refractive index of the respective wavelength-dispersive element 1251a-d. Since the wavelength is tuned by the light source 101, the beam is deflected along both the first angle θ and the second angle φ. During wavelength tuning, the distance to the objects can be calculated for each beam emission angle. As can be seen in the example of detection scan 1200, when the beam wavelength is tuned in segment A0, the beam is continuously deflected along the second angle φ. The distance can be calculated for each beam deflection angle. During this beam control, the beam is also deflected along the first angle θ. In this way, the field of view (FOV) can be scanned using a single wavelength tuning.

[0053] Referring to Fig. Figure 14a shows an example of rescanning using a reference interferometer. In one embodiment, a LIDAR system 1400 can include a reference interferometer 1401 positioned such that a portion of the beam from the light source 101 is received by the reference interferometer. In some embodiments, the portion of the beam from the light source 101 is directed towards the reference interferometer 1401 via a beam splitter 1401. In some embodiments, the reference interferometer 1401 can be a Mach-Zehnder interferometer. The reference interferometer 1401 can be used to generate a beat signal 1451 corresponding to a reference signal 1471 of the beam over a sweep of the light source. The reference interferometer can be used to identify the segments in the external environment even when the frequency sweep (e.g.,(Scanning or tuning) is not linear, or if the time interval is not identical for each segment. The reference interferometer signals (e.g., the beat signal 1451) can be used to compensate for the nonlinearity of the signals collected by detector 103 and / or the signals from light source 101.

[0054] For example, the reference signal 1471 may be intentionally or unintentionally nonlinear due to limitations of the light source 101. The nonlinearity of the reference signal 1471 can distort the time the beam is directed over certain sections of the FOV (e.g., segments A0, A1, or A2). As a result, calculations of object signal positions and object signal amplitudes may also be distorted. To enable the LIDAR system 1400 (e.g., the control circuit 180) to correct these distortions while calculating the distance and velocity of one or more objects in the FOV, the beat signal 1451 can be used as a reference. For example, the beat signal 1451 can indicate the time the object beam sweeps over each section (e.g., A0, A1, and A2) of the FOV.In some embodiments, the beat signal 1451 can indicate the time and angular position of the object beam by creating a cosine curve where each cycle of the cosine corresponds to a segment of the FOV. Thus, the beat signal 1451 of the reference interferometer 1401 can be used to identify the segments onto which the beam 1471 is projected or swept over specific sections of the FOV, even if there is nonlinearity in the reference signal. Furthermore, the beat signal 1451 can also be used to identify the time at which the up-ramp and down-ramp regions of a frame occur, even if they are not identical. In other words, the beat signal 1451 can be used by the processor 182 to compensate for the nonlinearity of the frequency sweep and to ensure that accurate positions, distances, and velocities are measured for each object in the FOV.In some embodiments, the LIDAR system 1400 can calculate and compensate for the non-linearity of the reference signal 1471 by detecting the reference signal 1451 (e.g. via the interferometer) and recording the times when the reference beam 1471 is at certain frequencies, and cross-referencing the received object signals based on the recording.

[0055] Referring to Fig. Figure 14b shows an example of the segmentation 1450 of an interference signal 1480, which was collected by the detector 103 using the reference signal 1481 from the reference interferometer 1401. The interference signal 1480 can be rescaled to the frequency domain with constant frequency intervals using the corresponding reference signal 1481 to generate a newly sampled interference signal 1483. Each segment, such as the segment signal 1484, of the newly sampled interference signal 1483 can be parsed from the newly sampled interference signal 1483. In some embodiments, the distance of the objects in each individual segment is calculated or determined by using a frequency counter. In some embodiments, the distance of the objects in each respective segment is determined based on a generated FFT signal 1485 of the segment.It is understood that the re-sampling of the interference signal 1480 can be performed either before, in the middle or after the segmentation of the interference signal 1480.

[0056] Referring to Fig. Figure 15 shows an example of signal segmentation 1500 using window functions. That is, the segmentation of an interference signal 1501 can be performed using window functions. For example, a window function 1502 can be defined for a specific segment and used by the control circuit 180. The window function 1501 for the specific segment of the external environment is convolved with the interference signal 1501 to generate a windowed interference signal 1503. In some embodiments, the windowed interference signal 1503 can then be used to generate an FFT for calculating the distance to objects corresponding to the specific segment. In some embodiments, the window function 1502 can include a Gaussian window, a Hann window, and / or a rectangular window.In various embodiments, the window functions 1502 for adjacent segments can be overlapped or have a gap, depending on whether the control circuit 180 has determined the specific segments as ROI.

[0057] Referring to Fig. Figure 16 presents an example of generating LIDAR data 1600 from FFT data. For example, after segmenting the interference signal (such as interference signal 1501), an FFT 1601 of the segmented interference signal can be generated by the control circuit 180. The control circuit 180 can then detect or determine peaks within the FFT 1601 (e.g., one or more FFTs corresponding to each segment) and generate a density representation 1603 (e.g., a two-dimensional peak representation). Thus, the control circuit 180 is able to generate a density representation for the FOV by using the FFT signals obtained from the interference signals detected or collected during the FOV scan. In some embodiments, the peak in the FFT signal 1601 is determined via a maximum signal detection algorithm, a theoretical fit, such as... B. a Gaussian fit, and / or other estimation algorithms detected.

[0058] Referring to Fig. Figures 17a-e show examples of LIDAR scanning using a beam scanner. Fig. Figure 17a represents an optical beam-guiding device 1700, which includes a beam scanner 1701 and a wavelength-dispersive element 1702. For example, an incident beam is directed onto the wavelength-dispersive element 1702 and towards a reflecting beam scanner 1701. The beam scanner 1701 is rotatable about an axis (e.g., connected to an actuator) and is able to deflect the beam by an angle (e.g., the first angle θ or the second angle φ) into the external environment. Beam tuning allows the beam to be deflected by a second angle into the external environment. In some embodiments, the beam scanner 1701 is a mirror, a polygon, or another shape with a reflective coating.

[0059] Fig. Figure 17b represents an optical beam-guiding device 1725 that includes a wavelength-dispersive element 1726 mounted on a beam scanner 1727. An incident beam is directed onto the wavelength-dispersive element 1726 mounted on the beam scanner 1727. The beam scanner 1727 can be rotatable about an axis (e.g., connected to an actuator) and is capable of directing the beam by an angle (e.g., the first angle θ or the second angle φ) into the external environment. Beam tuning allows the beam to be directed by a second angle into the external environment. In some embodiments, the beam scanner 1727 is a mirror, a polygon, or another shape with a coating that allows the arrangement of gratings on it.

[0060] Fig. Figure 17c shows an optical beam-guiding device 1750, which includes a wavelength-dispersive element 1751 mounted on a transmissive beam scanner 1752. An incident beam is directed into the beam scanner 1752, which directs the incident beam from one side through a wavelength-dispersive element 1751 located on its side. The beam scanner 1752 can be rotatable about an axis (e.g., connected to an actuator) and is capable of directing the beam by an angle (e.g., the first angle θ or the second angle φ) into the external environment. Beam tuning allows the beam to be directed by a second angle into the external environment. In some embodiments, the beam scanner 1752 is a polygon or another shape. In some embodiments, the beam scanner 1752 is made of glass, fibers or a polymer that allows the beam to pass through.

[0061] Fig. 17d represents an optical beam steering device 1775 which includes a wavelength-dispersive element 1776 arranged in a transmissive beam scanner 1777. Fig. Figure 17e shows a top view of an optical beam steering device 1780, such as the optical beam steering device 1775. Fig. Figure 17d shows an incident beam being directed into the beam scanner 1777 towards the wavelength-dispersive element 1776, which is arranged on the inside. The beam scanner 1777 can be rotatable about an axis (e.g., connected to an actuator) and is capable of deflecting the beam by an angle (e.g., the first angle θ or the second angle φ) into the external environment. Beam tuning allows the beam to be deflected by a second angle into the external environment. Furthermore, the external shape of the beam scanner 1777 can also serve as an optical element that deflects the beam into the external environment at a larger or smaller angle. In some embodiments, the beam scanner 1777 consists of glass, fibers, or a polymer that transmits the beam. In some embodiments, the beam scanner 1777 is a polygon, circle, square or some other shape.

[0062] Referring to Fig. 18a-b are examples of LIDAR scanning using the beam guidance devices of the Fig. 17a-e. However, it should be understood that the ones in the Fig. The examples shown in 18a-b do not refer to the devices of Fig. are limited to 17a-e. For example, the Fig. 18a-b are used to explain the two configurations in which wavelength tuning is assigned to the slow axis and the fast axis, respectively, in two-dimensional beam control. Fig. Figure 18a shows an example of a LIDAR scan 1800 along the fast axis. Fig. Figure 18b presents an example of a LiDAR scan at 1850 along the slow axis. Now, referring to Fig. 18a, when the wavelength tuning beam is assigned to the fast axis, the wavelength tuning (e.g., full scan from the first to the last frequency) is repeated N times with N additional beam scans (e.g., B1-BN).

[0063] Referring to Fig. 18b, when the wavelength tuning beam steering is assigned to the slow axis, the beam is steered N times with additional beam steering during each wavelength tuning. If the frame rate is set to a fixed value, the tuning period for the slow axis scan is 1 greater than the fixed value, but the tuning period for the fast axis scan is 1 divided by the fixed value divided by N. Thus, the maximum detection range for the slow axis scan is N times longer than the maximum detection range for the fast axis scan for the same frame rate.

[0064] Referring to Fig. Figure 19 shows examples of LiDAR scanning from 1950 using a microelectromechanical (MEMS) scanner. Fig. Figure 19 includes an optical beam-guiding device 1900 comprising a microelectromechanical (MEMS) mirror 1951 together with a wavelength-dispersive element 1952. If beam guidance is achieved by wavelength tuning for the slow axis of a two-dimensional beam guidance system, and a beam scanner such as a polygon scanner, as described above, is used for the fast axis, the beam will be guided in the same direction on each scan (e.g., from left to right in the figure). If a different type of beam scanner, such as the MEMS mirror 1951, is used, the beam can be scanned in a rasterized pattern. That is, the beam can be scanned from left to right on a first scan 1952 and from right to left on a second (e.g., subsequent) scan 1953, and so on. Accordingly, the order of the segments in each section of the interference signal 1901 also changes during the process and / or the creation of the density diagrams.

[0065] Referring to Fig. Figure 20 illustrates zero-padding 2000 for increasing the number of FFT bins. The total number of FFT bins and the size of each FFT bin are determined by sampling the data points used for FFT analysis. In this example, a zero signal is added to the original beat signal to increase the total number of sampled data points. As a result, the total number of FFT bins can be increased, and the size of each individual FFT bin can be decreased. This allows for increased distance resolution of the FFT signals. In some embodiments, the zero signal can be added before or after (or before and after) the original beat signal. In some embodiments, zero-padding can be performed before or after re-sampling, as described above. In some embodiments, the total number of added zero signals can be varied for the different segments.

[0066] The preceding description of illustrative embodiments has been presented for illustrative and descriptive purposes. It is not intended to be exhaustive or limiting with respect to the exact disclosed embodiment, and modifications and variations are possible in light of the above teachings or may be derived from the practice of the disclosed embodiments.

[0067] While certain embodiments have been illustrated and described, changes and modifications should be able to be made in accordance with common technical knowledge without deviating from the technology in its broader aspects as defined in the following claims.

[0068] The embodiments described herein for illustrative purposes can be suitably implemented in the absence of one or more elements, limitations, or restrictions not specifically disclosed herein. For example, the terms "comprehensive," "including," "containing," etc., are to be understood broadly and without limitation. Furthermore, the terms and expressions used herein have been employed as descriptive terms and not as limitations, and it is not intended that the use of such terms and expressions excludes equivalents of the features or sections thereof shown and described, but it is acknowledged that various modifications within the scope of the claimed technology are possible.Furthermore, the phrase "essentially consisting of" is to be understood as including the specifically named elements and those additional elements that do not substantially affect the fundamental and novel properties of the claimed technology. The phrase "consisting of" excludes all unnamed elements.

[0069] The present disclosure is not to be limited with respect to the embodiments described in this application. Many modifications and variations can be made without departing from its spirit and scope, as is obvious to the person skilled in the art. Functionally equivalent methods and compositions within the scope of the disclosure, in addition to those listed herein, will be apparent to the person skilled in the art from the preceding descriptions.

[0070] Such modifications and variations are said to fall within the scope of the appended claims. The present disclosure is limited only by the conditions of the appended claims, together with the full scope of the equivalents to which those claims refer. It is to be understood that this disclosure is not limited to specific processes, reagents, compositions, or biological systems, which may, of course, vary.

[0071] It is also understood that the terminology used herein serves only to describe certain embodiments and is not to be understood as limiting. The person skilled in the art also understands that "based on" is to be understood as "at least based on" unless expressly stated otherwise.

[0072] As a person skilled in the art understands, all the areas disclosed herein, for all purposes, particularly with regard to providing a written description, also include all possible sub-areas and combinations thereof. Each area listed can easily be recognized as sufficiently descriptive and allows the same area to be subdivided into at least equal halves, thirds, quarters, fifths, tenths, etc. As a non-limiting example, each area described herein can readily be subdivided into a lower third, a middle third, and an upper third, etc. As will be clear to a person skilled in the art, all expressions such as "up to," "at least," "greater than," "less than," and the like include the numbers mentioned and refer to areas that can subsequently be subdivided into sub-areas as described above. Finally, as a person skilled in the art understands, an area includes every single element.

[0073] All publications, patent applications, granted patents and other documents referenced in this description are included herein by reference, provided that each individual publication, patent application, granted patent or other document has been expressly and individually indicated as being fully included by reference.

[0074] Definitions contained in texts incorporated by reference are excluded to the extent that they contradict the definitions in this disclosure.

[0075] Further embodiments are set out in the following claims.

Claims

[1] System (100; 200; 400; 500; 1000; 1200; 1400) for detecting light and measuring distance (LIDAR), the system comprising: a light source (101; 101a-b) configured to produce a beam that is tunable over a range of frequencies; an optical beam steering device (102; 1700; 1725; 1750; 1775) positioned to receive at least one section of the beam and configured to sweep the beam over a range of angles in a field of view (FOV) (190), each discrete frequency of the beam corresponding to a different angle in the FOV (190); a detector (103; 103a-b) positioned to receive sections of the beam reflected by an object (191a-c; 622a, 622b) within the FOV (190) and configured to generate an interference signal (1501) based on the received sections of the beam; and a processor (181) that is communicatively coupled to the detector (103; 103ab), wherein the processor (181) is configured to: to cause the light source (101; 101a-b) to tune the beam from a first frequency to a second frequency; and to calculate an area of ​​an object (191a-c; 622a, 622b) corresponding to either the first frequency or the second frequency within the FOV (190), wherein the processor (181) for calculating the distance of the object (191a-c; 622a, 622b) is configured to segment the interference signal (1501) using a window function (1502), wherein the window function (1502) corresponds to a specific segment of the FOV (190). [2] System (100; 200; 400; 500; 1000; 1200; 1400) according to claim 1, further comprising an N number of light sources (101a-b) each configured to generate a beam and an N number of detectors (103a-b) each configured to receive portions of the respective beams and generate respective interference signals (1501), wherein the optical beam guiding device (102; 1700; 1725; 1750; 1775) comprises a first optical element (211; 1001) and a wavelength-dispersive element (104; 220; 520; 620; 1020). [3] System (100; 200; 400; 500; 1000; 1200; 1400) according to claim 1, wherein the processor (181) is further configured to: to determine a region of interest (ROI) within the FOV (190) based on the object (191a-c; 622a, 622b); and to cause the light source (101; 101a-b) to sweep from a third frequency to a fourth frequency, where the third frequency and the fourth frequency correspond to the ROI. [4] System (100; 200; 400; 500; 1000; 1200; 1400) according to claim 1, further comprising an N number of detectors (103a-b) each configured to receive sections of the beam and generate corresponding interference signals (1501), wherein the optical beam guiding device (102; 1700; 1725; 1750; 1775) comprises a first optical element (490) and an N number of wavelength-dispersive elements (420a-b). [5] System (100; 200; 400; 500; 1000; 1200; 1400) according to claim 1, further comprising an N number of detectors (103a-b) each configured to receive sections of the beam and generate corresponding interference signals (1501), wherein the optical beam guiding device (102; 1700; 1725; 1750; 1775) comprises a first optical element (1001), a wavelength-dispersive element (1020) and an N number of mirrors. [6] System (100; 200; 400; 500; 1000; 1200; 1400) according to claim 1, further comprising: an interferometer (1401); and a beam dividing device positioned between the light source (101; 101a-b) and the optical beam guiding device (102; 1700; 1725; 1750; 1775), wherein the beam dividing device is configured to receive the beam generated by the light source (101; 101a-b) and to divide the beam into an object beam directed towards the optical beam guiding device (102; 1700; 1725; 1750; 1775) and a reference beam (1471) directed towards the interferometer (1401); wherein the interferometer (1401) is configured to detect frequencies of the reference beam (1471). [7] System (100; 200; 400; 500; 1000; 1200; 1400) according to claim 1, wherein, in order to calculate the distance of the object (191a-c; 622a, 622b), the processor (181) is configured to: to filter the interference signal with a low-pass filter (LPF), wherein the LPF has a cutoff frequency based on a maximum beat frequency corresponding to a maximum distance; and to determine the distance using a frequency counter or a fast Fourier transform (FFT) of the filtered interference signal. [8] System (100; 200; 400; 500; 1000; 1200; 1400) according to claim 1, wherein the light source (101; 101a-b) comprises a cascade of several tunable lasers, each of the tunable lasers comprising a different sweep rate and bandwidth. [9] System (100; 200; 400; 500; 1000; 1200; 1400) according to claim 1, wherein the optical beam steering device comprises a 1xN splitter and a wavelength dispersive element, and wherein each path of the 1xN splitter comprises a different time delay. [10] System (100; 200; 400; 500; 1000; 1200; 1400) according to claim 1, wherein the optical beam steering device (102; 1700; 1725; 1750; 1775) comprises a 1xN splitter (1210) and an N number of wavelength-dispersive elements (1251a-d), wherein each of the N number of wavelength-dispersive elements (1251a-d) corresponds to an output of the 1xN splitter (1210), and wherein each path of the 1xN splitter (1210) comprises a different optical phase delay. [11] System (100; 200; 400; 500; 1000; 1200; 1400), comprising: a light source (101; 101a-b) configured to produce a beam that is tunable over a range of frequencies; an optical beam steering device (102; 1700; 1725; 1750; 1775) positioned to receive at least one section of the beam and configured to sweep the beam over a range of angles in a field of view (FOV) (190), each discrete frequency of the beam corresponding to a different angle in the FOV (190); a detector (103; 103a-b) positioned to receive sections of the beam reflected by an object (191a-c; 622a, 622b) within the FOV (190) and configured to generate an interference signal (1501) based on the received sections of the beam; and a processor (181) that is communicatively coupled to the detector (103; 103ab), wherein the processor (181) is configured to: to cause the beam to sweep from a first frequency at a first time to a second frequency over a period of time; and based on the interference signal (1501) to calculate a distance of an object (191a-c; 622a, 622b) in the FOV (190), wherein the processor (181) for calculating the distance of the object (191a-c; 622a, 622b) is configured to segment the interference signal (1501) using a window function (1502), wherein the window function (1502) corresponds to a specific segment of the FOV (190). [12] System (100; 200; 400; 1400) according to claim 11, wherein the processor (181) is further configured to generate a two-dimensional peak representation of the FOV (190) based on the interference signal (1501). [13] System (100; 200; 400; 500; 1000; 1200; 1400) according to claim 12, wherein to generate the two-dimensional tip representation the processor (181) is configured to: to segment the interference signal (1501) into several segments, each of which corresponds to a section of the FOV (190); to generate a fast Fourier transform (FFT) for each of the multiple segments; and to detect a peak for each FFT. [14] System (100; 200; 400; 500; 1000; 1200; 1400) according to claim 11, wherein the optical beam guidance device (102; 1700; 1725; 1750; 1775) comprises a beam scanner (1701; 1727; 1752; 1777) and a wavelength dispersive element (1702; 1726; 1751; 1776) and wherein the beam scanner (1701; 1727; 1752; 1777) is rotatable via an actuator. [15] System (100; 200; 400; 500; 1000; 1200; 1400) according to claim 14, wherein the beam scanner (1701; 1727; 1752; 1777) is transparent and the wavelength-dispersive element (1702; 1726; 1751; 1776) is arranged inside the beam scanner (1701; 1727; 1752; 1777). [16] Method for detecting an object (191a-c; 622a, 622b) within a field of view (FOV) (190) of a detection system (100; 200; 400; 500; 1000; 1200; 1400), the method comprising: Control, via a processor (181), a light source (101; 101a-b), to project a beam which is swept from a first frequency to a last frequency, starting from a first time point over a first time interval; Directing the beam into a FOV (190) at angles dependent on the frequency; Generating an interference signal (1501) based on received sections of the beam from an object (191a-c; 622a, 622b) in the FOV (190); and Determine, via the processor (190), a position of the object (191a-c; 622a, 622b) relative to the detection system (100; 200; 400; 500; 1000; 1200; 1400), wherein the determination of the position of the object (191a-c; 622a, 622b) includes segmenting the interference signal (1501) using a window function (1502), wherein the window function (1502) corresponds to a specific segment of the FOV (190). [17] Method according to claim 16, wherein controlling the light source (101; 101a-b) comprises: Control, via the processor (181), an N number of light sources (101a-b) to project respective beams from the first frequency to the last frequency; and Generating, via an N number of detectors (103a-b), respective interference signals (1501) based on respective received sections of the beams from objects (191a-c; 622a, 622b) within the FOV (190). [18] Method according to claim 16, further comprising: Determine, via the processor (181), a region of interest (ROI) in the FOV (190); and Controlling the light source (101; 101a-b) to project a beam from a third frequency to a fourth frequency over a second time period, where the third frequency and the fourth frequency correspond to the ROI. [19] Method according to claim 17, wherein directing the beam into the FOV (190) comprises: Reception of the beam by a variety of wavelength-dispersive elements (104; 220; 420a-b; 520; 620; 1020; 1251a-d; 1702; 1726; 1751; 1776); and Directing the beam from each of the plurality of wavelength-dispersive elements across the FOV (190), wherein the FOV (190) is two-dimensional.

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