A DToF-based measurement system and method

Abstract

This application relates to the field of optical detection technologies, and particularly to a measurement system and method based on DToF. The measurement system includes: a transmitter, a collector, and a control and processing circuit. The transmitter is configured to emit an optical signal towards a target object; the collector is configured to actuate pixels under the control of the control and processing circuit to receive at least part of the optical signal reflected by the target object and generate measurement data; the control and processing circuit is configured to determine the number of pixels that cause a response in a given time period for the actuated pixels, and use the number as the confidence level of the measurement data. Embodiments of this application can improve the accuracy of the measurement system.

Description

Technical Field

[0001] This application relates to the field of optical detection technology, and in particular, to a measurement system and method based on Direct Time of Flight (DToF). Background Art

[0002] The Time of Flight (ToF) technology can be used to measure the distance to a target to obtain a depth image containing the depth value of the target. Optical measurement systems based on ToF technology have been widely used in fields such as consumer electronics, unmanned driving, AR / VR, etc.

[0003] An optical measurement system based on ToF technology generally includes a transmitter and a collector. The transmitter is used to emit a light beam to irradiate the target field of view, and the collector is used to collect the reflected light beam. The distance of the object is calculated by calculating the flight time of the light beam from emission to reflection and reception. The ToF technology is divided into Direct Time of Flight (DToF) technology and Indirect Time of Flight (IToF) technology. Among them, the DToF technology measures the flight time of photons in the light beam from emission to reception based on Time-Correlated Single Photon Counting (TCSPC) technology; the IToF technology measures the phase delay of the reflected light beam relative to the emitted light beam, and then calculates the flight time from the phase delay. The DToF technology has the advantages of high signal-to-noise ratio, good sensitivity, high accuracy, etc., and has received more and more extensive attention.

[0004] However, in actual applications, the collector inevitably receives ambient light signals and the like when receiving optical signals, which in turn leads to a decrease in measurement accuracy.

[0005] The disclosure of the above background art content is only used to assist in understanding the concept and technical solution of this application, and it does not necessarily belong to the prior art of this application. Without clear evidence indicating that the above content was publicly available before the filing date of this application, the above background art should not be used to evaluate the novelty and inventiveness of this application. Summary of the Invention

[0006] The purpose of the embodiments of this application is to provide a measurement system and method based on dToF, aiming to solve one or more technical problems in the related art.

[0007] To achieve the above object, in a first aspect, an embodiment of the present application provides a DToF-based measurement system, including: a transmitter, a collector, and a control and processing circuit. The transmitter is configured to emit an optical signal towards a target object; the collector is configured to actuate pixels under the control of the control and processing circuit to receive at least part of the optical signal reflected back by the target object and generate measurement data; the control and processing circuit is configured to determine the number of pixels that cause a response in a given time period by the actuated pixels, and use the number as the confidence level of the measurement data.

[0008] As an implementation manner of the first aspect, the given time period is a first preset duration time period starting from the time point when the first pixel responds, or the given time period is a second preset duration time period starting from the time when the optical signal is emitted.

[0009] As an implementation manner of the first aspect, the measurement data includes histogram data; the actuated pixels output photon signals to a readout circuit in response to the incidence of photons, and the readout circuit is configured to generate the histogram data according to the photon signals.

[0010] As an implementation manner of the first aspect, the control and processing circuit calculates the distance information of the target object only based on the histogram data whose confidence level is greater than or equal to a preset threshold.

[0011] As an implementation manner of the first aspect, the measurement data includes the distance information of the target object; the control and processing circuit is configured to calculate the distance information of the target object according to the histogram data corresponding to the first pixel that causes a response among the actuated pixels.

[0012] As an implementation manner of the first aspect, the control and processing circuit is further configured to use the distance information whose confidence level is greater than or equal to a preset threshold as the effective distance information.

[0013] As an implementation manner of the first aspect, the transmitter further includes a driver connected to the light source, and the light source emits an optical signal towards the target object under the drive of the driver and under the control of the control and processing circuit.

[0014] As an implementation manner of the first aspect, the transmitter further includes a transmitting optical component, and the transmitting optical component is configured to project the optical signal onto the target object and form an illumination spot on the target object with the optical signal.

[0015] As an implementation manner of the first aspect, the collector further includes a receiving optical component, and the receiving optical component is configured to receive at least part of the optical signal reflected back by the target object and guide the at least part of the optical signal onto the pixels.

[0016] In a second aspect, an embodiment of the present application provides a measurement method, including: controlling a transmitter to emit an optical signal towards a target; synchronously actuating pixels of a collector to receive at least part of the optical signal reflected by the target and generate measurement data; determining the number of pixels that cause responses within a given time period by the actuated pixels, and using the number as the confidence level of the measurement data.

[0017] As an implementation of the second aspect, the given time period is a first preset duration period starting from the time point when the first pixel causes a response, or the given time period is a second preset duration period starting from the time when the optical signal is emitted.

[0018] As an implementation of the second aspect, the measurement data includes histogram data; the actuated pixels output photon signals to a readout circuit in response to the incidence of photons, and the readout circuit is configured to generate the histogram data according to the photon signals; the generating of the measurement data includes: calculating distance information of the target only according to the histogram data with a confidence level greater than or equal to a preset threshold.

[0019] As an implementation of the second aspect, the measurement data includes distance information of the target; the generating of the measurement data includes: calculating distance information of the target according to histogram data corresponding to the first pixel that causes a response among the actuated pixels; the measurement method further includes: using the distance information with a confidence level greater than or equal to a preset threshold as valid distance information.

[0020] In a third aspect, an embodiment of the present application provides an electronic device, including the measurement system described in the first aspect or any implementation of the first aspect; the transmitter and the collector of the measurement system are arranged on the same side of the electronic device body.

[0021] The beneficial effects of the embodiments of the present application are as follows: by determining the number of pixels that cause responses within a given time period by the actuated pixels and using the number as the confidence level of the measurement data, on the one hand, the given time period is used as the effective time period for pixel responses, and pixel responses in other time periods are considered noise, which has a good anti-interference effect in calculating the confidence level; on the other hand, the confidence levels of each measurement data can be obtained simultaneously, which can avoid the influence of invalid measurement information on the final measurement result, thereby improving the accuracy of the measurement system. Description of the Drawings

[0022] To more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0023] Figure 1 It is a schematic structural diagram of a measurement system based on DToF provided by an embodiment of the present application.

[0024] Figure 2 It is a schematic structural diagram of a pixel array provided by an embodiment of the present application.

[0025] Figure 3 It is a schematic connection diagram of a collector and a control and processing circuit provided by an embodiment of the present application.

[0026] Figure 4 It is a schematic implementation flowchart of a measurement method provided by an embodiment of the present application.

[0027] Figure 5 It is a schematic structural diagram of an electronic device provided by an embodiment of the present application. Detailed implementation manners

[0028] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clear and understandable, the following further details the present application in conjunction with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0029] It should be noted that when a component is referred to as "fixed to" or "disposed on" another component, it can be directly on the other component or indirectly on the other component. When a component is referred to as "connected to" another component, it can be directly connected to the other component or indirectly connected to the other component.

[0030] It should be understood that the orientation or positional relationship indicated by the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or component referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present application.

[0031] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of this application, "a plurality of" means two or more, unless otherwise specifically defined.

[0032] Please refer to Figure 1 , an embodiment of this application provides an optical measurement system 10. The optical measurement system 10 includes a transmitter 11, a collector 12, and a control and processing circuit 13.

[0033] In some embodiments, the transmitter 11 is configured to emit an emission beam 30 towards a target area 20. The emission beam 30 is emitted into the space of the target area 20 to illuminate the target object in the space. At least a part of the emission beam 30 is reflected by the target area 20 to form a reflected beam 40, and at least a part of the reflected beam 40 is received by the collector 12; the control and processing circuit 13 is respectively connected to the transmitter 11 and the collector 12, synchronizes the trigger signals of the transmitter 11 and the collector 12 to calculate the time required for the beam to be emitted, reflected, and then received or collected, that is, the flight time t between the emission beam 30 and the reflected beam 40. Further, the distance D of the corresponding point on the target object can be calculated by the following formula:

[0034] D = c·t / 2

[0035] where c is the speed of light.

[0036] In some embodiments, the transmitter 11 includes a light source 111, an emission optical component 112, a driver 113, etc. Among them, the light source 111 can be a single light source such as a light-emitting diode (LED), a laser diode (LD), an edge-emitting laser (EEL), a vertical-cavity surface-emitting laser (VCSEL), or a one-dimensional or two-dimensional light source array composed of multiple light sources. Preferably, the light source array is a VCSEL array light source chip formed by generating multiple VCSEL light sources on a single semiconductor substrate, and the arrangement of the light sources in the light source array can be regular or irregular. The beam emitted by the light source 111 can be visible light, infrared light, ultraviolet light, etc. The light source 111 emits a beam outward under the control of the driver 113.

[0037] In some embodiments, the light source 111 is configured as an array of light sources composed of multiple light sources. The light source array includes multiple groups of light sources. Each time a group of light sources is turned on to emit a speckle beam towards the target area until the last group of light sources is turned on, scanning of the target area is achieved. Herein, a group of light sources can be a single light source; alternatively, a group of light sources can also be multiple light sources arranged as a linear light source, and the linear light source is formed by sequentially arranging multiple light sources; or, a group of light sources can further be multiple light sources arranged in other shapes such as a rectangle or an L shape, etc., and the present application does not limit this. It should be noted that, more generally, the emitter is configured to activate a group of light sources to emit optical signals at a time, and a group of light sources is the light source for a given area during each scan of the target object, and the working light source can be one or more light sources.

[0038] In one embodiment, the light source 111 emits pulsed light beams outward at a certain frequency (or pulse period) under the control of the driver 113 for DTOF measurement, and the frequency is set according to the measured distance. It can be understood that a part of the control and processing circuit 13 or a sub-circuit independent of the control and processing circuit 13 can also be used to control the light source 111 to emit light beams.

[0039] The emission optical component 112 receives the light beams emitted from the light source 111, shapes them, and projects them onto the target area. In one embodiment, the emission optical component 112 receives the pulsed light beams from the light source 111, and optically modulates the pulsed light beams, such as modulation by diffraction, refraction, reflection, etc., and then emits the modulated light beams into space, such as focused light beams, floodlight beams, structured light beams, etc. The emission optical component 112 can be one or a combination of forms such as a lens, a liquid crystal component, a diffractive optical component, a microlens array, a metasurface optical component, a mask plate, a mirror, a MEMS galvanometer, etc.

[0040] In some embodiments, the collector 12 includes a pixel array 121, a filtering unit 122, and a readout circuit array ( Figure 1(not shown in the figure). Among them, the filtering unit 122 is used to filter out background light or stray light. The pixel array 121 is composed of multiple pixels. The pixel array 121 is configured to actuate all or part of the pixels under the control of the control and processing circuit 13 to collect at least part of the optical signal reflected by the target object and generate corresponding photon signals. The readout circuit array is composed of multiple readout circuits, and the readout circuits are used to receive photon signals for processing to generate histograms. In one embodiment, the pixel array 121 is a SPAD array composed of Single Photon Avalanche Diodes (SPADs). SPADs are also known as Geiger Mode Avalanche PhotoDiodes (GM-APDs), and are detectors capable of capturing individual photons with a time-of-arrival resolution on the order of dozens of picoseconds. They can be fabricated in dedicated semiconductor processes or in standard Complementary Metal Oxide Semiconductor (CMOS) technologies. The pixel array 121 is connected to the readout circuit array. In one embodiment, each pixel in the pixel array 121 is correspondingly connected to a readout circuit. The pixel outputs a photon signal to the readout circuit in response to the incidence of photons, and the readout circuit receives and accumulates the photon signals from the correspondingly connected pixels to generate a histogram of the pixel. In some embodiments, the readout circuit includes one or more of devices such as signal amplifiers, Time-to-Digital Converters (TDCs), and Analog-to-Digital Converters (ADCs).

[0041] In an optical measurement system based on DToF technology, there is a one-to-one correspondence between the emission field of view of the emitter 11 and the acquisition field of view of the collector 12. After the emitter 11 emits each spot beam into the target field of view, it will be reflected and imaged onto the corresponding pixel. In addition, in order to receive as much optical signal of the reflected light spot as possible, it is usually necessary to combine multiple pixels together to form a pixel group to jointly collect the optical signal in a reflected light spot. At this time, each time a spot beam is emitted, the corresponding pixel group will be activated simultaneously to collect the reflected light spot. As Figure 2 shown, since the size of the reflected light spot is larger than the size of a single pixel, it is usually set that the spot beam projected by a light source can be imaged onto a pixel group 21 of the pixel array. Each pixel group 21 includes multiple pixels. Considering the displacement caused by system errors or parallax, it is usually also set that a pixel group with a number of pixels larger than the size of the reflected light spot is used to collect the reflected light spot. The reflected light spot is imaged at any position of the pixel group. For example, each pixel group includes 4 pixels 22, or each pixel group includes 36 pixels, etc.

[0042] The inventors of the present application have found that in some cases, some pixels are exposed not by effective light sources, but by environmental light noise exposure or dark count exposure of the device, etc., resulting in pixel responses. Therefore, in some embodiments of the present application, a process of determining the confidence of measurement data such as histograms or correlation results (such as distance information) is added. Specifically, the number of pixels that cause responses in a given time period in the actuated pixel group is determined, and this number is used as the confidence of the measurement data. This confidence can be used as a reference quantity for subsequent judgment of the influence of this histogram or its correlation results and other measurement data on the results. For example, according to the confidence, algorithms such as point cloud computing can be assisted to improve accuracy. For example, when calculating point clouds using distance information, the influence of less reliable distance information on the results can be avoided. In addition, in practical applications, due to the limitations of the device itself or photoelectric conversion, there are differences in the time points at which different pixels in the same pixel group cause responses. In some embodiments of the present application, the distance information of the target object is calculated according to the histogram of the first pixel that causes a response in the actuated pixels, or the distance information of the target object is calculated according to the histogram of the first pixel that causes a response in each actuated pixel group, or the distance information of the target object is calculated according to the histogram with a confidence greater than or equal to a preset threshold.

[0043] The control and processing circuit 13 synchronizes the trigger signals of the transmitter 11 and the collector 12. Optionally, the control and processing circuit 13 can control the light sources that need to be turned on and / or off at each given time, as well as the pixels that need to be actuated (or started) and / or deactivated. The histograms generated by the histogram circuit, other characteristics of the pixels (such as photon arrival time, etc.) can be output to the control and processing circuit 13 for its subsequent use. In some embodiments, the control and processing circuit 13 determines the number of pixels that cause responses in the actuated pixels in a given time period as the confidence of the measurement data. By setting the confidence, it can be determined whether the pixel response is caused by the light source emitting a light signal, environmental light noise, or the dark count of the device. In some other embodiments, the control and processing circuit 13 determines the first pixel that causes a response in the actuated pixels, and calculates the flight time of the light beam from emission to collection according to the histogram output by the readout circuit corresponding to this pixel. Further, the distance information of the target object to be measured can be calculated based on the flight time. Further, the control and processing circuit 13 can also use the distance information with a confidence greater than or equal to a preset threshold as the effective distance information. In some other embodiments, the control and processing circuit 13 can also calculate the distance information of the target object according to the histogram data with a confidence greater than or equal to a preset threshold.

[0044] In one embodiment, a pixel responds to an incident single photon and outputs a photon signal. The readout circuit receives the photon signals from the correspondingly connected pixels and processes them to generate a histogram. The control and processing circuit 13 obtains the flight time of the light beam based on the histogram. Further, the distance information of the target object can be calculated based on the flight time. Specifically, the readout circuit calculates the number of photons collected by the correspondingly connected pixels to form consecutive time bins, and these time bins are connected together to form a statistical histogram for reproducing the time sequence of the reflected light pulse; the control and processing circuit 13 uses peak matching and filtering detection to identify the flight time of the light beam from emission to reception. It can be understood that the control and processing circuit 13 can be an independent dedicated circuit, such as a dedicated SOC chip, FPGA chip, ASIC chip, etc., or can include a general-purpose processing circuit.

[0045] In some embodiments, the measurement system 10 further includes a memory. The memory can be used to store pulse coding programs, the excitation time, emission frequency, etc. of the light beam emitted by the coded program-controlled light source 111. The memory can be used to store information such as time information, histogram, flight time, distance information, confidence level, etc.

[0046] In one embodiment, the control and processing circuit 13 is configured to store the flight time, distance information, and confidence level in the memory after calculating the flight time, distance information, and confidence level.

[0047] In one embodiment, the control and processing circuit 13 is configured to store only the distance information and its confidence level with a confidence level greater than or equal to a preset threshold after calculating the distance information and the confidence level.

[0048] In one embodiment, the control and processing circuit 13 is configured to delete measurement data such as histograms or distance information with a confidence level less than or equal to a preset threshold.

[0049] In one embodiment, the preset threshold can be set to any value greater than half of the number of pixels occupied by the pixel group. The present application does not specifically limit the preset threshold.

[0050] In some embodiments, the measurement system 10 may further include devices such as a color camera, an infrared camera, an IMU, etc. The combination with these devices can achieve more diverse functions, such as 3D texture modeling, infrared face recognition, SLAM, etc.

[0051] In one embodiment, the control and processing circuit 13 determines the number of pixels that cause a response among a plurality of actuated pixels within a given time period, where the given time period is a first preset duration period starting from the time point when the first pixel responds, or a second preset duration period starting from the time point when the light source emits an optical signal. It should be noted that the durations of the first preset duration period and the second preset duration period may be the same. As a non-limiting example, for instance, the emission light pulse width is that short. The confidence calculated by this method can be more accurate, reducing the interference of ambient light and dark counts, and selecting a time period before and after the effective optical pixel avalanche as the effective time period for calculating the confidence.

[0052] It should be noted that in some practical applications, without knowing the target information, it is usually impossible to predict the effective light exposure time. Therefore, the first avalanche can be considered effective, and then only a short time period (i.e., the first preset duration period) after this avalanche is selected as the effective time period, and the avalanches in other time periods are considered noise, which has a certain anti-interference effect in calculating the confidence. In some other practical applications, the approximate distance of the target is known, so the time of the effective optical pixel avalanche can be roughly estimated, and a narrow time period (i.e., the second preset duration period) including this time is set as the effective time period, and the avalanches in other time periods are considered noise, which has a certain anti-interference effect in calculating the confidence.

[0053] In one embodiment, the readout circuit includes a TDC circuit and a histogram circuit. As Figure 3 shown, each pixel in the collector is correspondingly connected to a TDC circuit and a histogram circuit. The pixel receives the pulsed optical signal reflected by the target and generates a photon signal. The TDC circuit receives and calculates the time interval of these photon signals and converts the time interval into a time code. The histogram circuit accumulatively counts the time codes output by the TDC circuit to draw a histogram. Continuing to refer to Figure 3 shown, the histogram circuit is electrically connected to the control and processing circuit, and the control and processing circuit can calculate the flight time of photons from emission to reception based on the histogram, and can further calculate the distance information of the target.

[0054] In some embodiments, continuing to refer to Figure 1 shown, the collector 12 further includes a receiving optical component 123. The receiving optical component 123, the filtering unit 122, and the pixel unit 121 are sequentially arranged along the propagation path of the optical signal. The receiving optical component 123 is configured to receive at least part of the light beam reflected by the target and guide the at least part of the light beam onto the pixel array 121 to image the target onto the pixel array.

[0055] In some embodiments, continuing to refer to Figure 1As shown, the transmitter 11 includes a light source 111 and a driver 113 for driving the light source 111. The light source 111 emits an optical signal in a given area (i.e., the aforementioned set of light sources, or working light sources) under the drive of the driver 113 and under the control of the control and processing circuit 13.

[0056] Further, in some embodiments, with continued reference to Figure 1 As shown, the transmitter 11 further includes a transmitting optical component 112. The transmitting optical component 112 is used to project the optical signal onto the target 20 and form an illumination spot on the target 20. Optionally, the transmitting optical component 112 includes, but is not limited to, one or a combination of a collimating mirror, a diffractive optical component, etc.

[0057] In some implementation manners, the light source 111 is a VCSEL array light source chip formed by generating multiple (Vertical Cavity Surface Emitting Laser, VCSEL) light sources on a single semiconductor substrate. Among them, the light source 111 can emit a pulsed light beam 30 to the target at a certain frequency (or pulse period) under the control of the control and processing circuit 13, and the pulsed light beam 30 is projected onto the target through the transmitting optical component 112 to form an illumination spot.

[0058] Figure 4 Shown is a measurement method provided by an embodiment of the present application. The measurement method can be applied to the dToF-based measurement system in any of the foregoing embodiments. In some embodiments, the measurement method can be executed by the control and processing circuit of the measurement system. In some embodiments, the measurement method can be executed by an electronic device.

[0059] As Figure 4 shown, the measurement method may include the following steps S41 to S43.

[0060] S41, control the transmitter to emit an optical signal towards the target.

[0061] In one embodiment, control the light source in the transmitter to emit an optical signal towards the target. The transmitter can be configured to include one light source or a light source array including multiple light sources.

[0062] In one embodiment, control a set of light sources in the transmitter to emit an optical signal at one time. A set of light sources can include one or more light sources.

[0063] S42, synchronously actuating the pixels in the collector to receive at least part of the optical signal reflected back by the target and generating measurement data.

[0064] In one embodiment, the measurement data includes histogram data. The actuated pixels output photon signals to the readout circuit in response to the incidence of photons, and the readout circuit is configured to generate histogram data based on the photon signals.

[0065] In one embodiment, the measurement data includes the distance information of the target. The control and processing circuit is configured to calculate the distance information of the target based on the histogram data corresponding to the first pixel that causes a response among the actuated pixels. By calculating the distance information of the target according to the histogram corresponding to the first pixel that causes a response among the actuated pixels, the amount of calculation is reduced, and computing power can be saved.

[0066] In one embodiment, several pixel groups of the synchronous actuation collector are actuated to receive at least part of the optical signal reflected back by the target. Each pixel group includes multiple pixels, and the pixel groups correspond to the light sources one by one.

[0067] S43. Determine the number of pixels among the actuated pixels that cause a response within a given time period, and use this number as the confidence level of the measurement data.

[0068] Wherein, the given time period is the first preset duration time period starting from the time point when the first pixel responds, or the second preset duration time period starting from the time when the optical signal is emitted.

[0069] In one embodiment, the measurement method may further include: using the distance information with a confidence level greater than or equal to a preset threshold as valid distance information.

[0070] In one embodiment, the measurement method may further include: deleting the distance information with a confidence level less than or equal to the preset threshold, or only storing the distance information with a confidence level greater than or equal to the preset threshold and its confidence level.

[0071] It should be noted that the measurement method in this embodiment uses the measurement system in any of the foregoing embodiments for distance measurement. The similarities between its technical solutions and the foregoing measurement system are not described herein again.

[0072] An embodiment of the present application further provides an electronic device. Refer to Figure 5 As shown, the electronic device 500 includes: a processor 50, a memory 51, and a computer program 52 stored in the memory 51 and executable on the processor 50, such as a program for optical detection. When the processor 50 executes the computer program 52, it implements the steps in the measurement method embodiment of any of the foregoing embodiments, such as Figure 3 the steps S31 to S33 shown.

[0073] Exemplarily, the computer program 52 can be divided into one or more modules / units, which are stored in the memory 51 and executed by the processor 50 to complete the present application. The one or more modules / units can be a series of computer program instruction segments capable of performing specific functions, and these instruction segments are used to describe the execution process of the computer program 52 in the electronic device 500.

[0074] Those skilled in the art can understand that Figure 5 merely being examples of the electronic device 500, they do not constitute a limitation on the electronic device 500. The electronic device 500 may include more or fewer components than those shown in the figure, or combine certain components, or have different components. For example, the electronic device 500 may further include input / output devices, network access devices, buses, etc.

[0075] The so-called processor 50 may be a central processing unit (CPU), or may also be other general-purpose processors, digital signal processors (DSPs), application specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0076] The memory 51 may be an internal storage unit of the electronic device 500, such as the hard disk or memory of the electronic device 500. The memory 51 may also be an external storage device of the electronic device 500, such as a plug-in hard disk equipped on the electronic device 500, a smart media card (SMC), a secure digital (SD) card, a flash card, etc. Further, the memory 51 may also include both the internal storage unit and the external storage device of the electronic device 500. The memory 51 is used to store the computer program and other programs and data required by the electronic device. The memory 51 may also be used to temporarily store data that has been output or is to be output.

[0077] An embodiment of the present application further provides an electronic device. The electronic device includes the measurement system of any one of the foregoing embodiments, wherein the transmitter and the collector of the measurement system are arranged on the same side of the electronic device body.

[0078] As a non-limiting example, the electronic device can be a lidar or the like.

[0079] An embodiment of the present application provides a computer-readable storage medium storing a computer program, and when the computer program is executed by a processor, the steps in the above-mentioned various measurement method embodiments can be implemented.

[0080] An embodiment of the present application provides a computer program product, and when the computer program product runs on an electronic device, the electronic device can implement the steps in the above-mentioned various measurement method embodiments.

[0081] In the above embodiments, the descriptions of the various embodiments have their own emphases. For the parts not detailed or recorded in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0082] Those of ordinary skill in the art can realize that the units and algorithm steps of the examples described in combination with the embodiments disclosed herein can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are executed in a hardware or software manner depends on the specific application and design constraints of the technical solution. Professional technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of this application.

[0083] In the embodiments provided by the present application, it should be understood that the disclosed device / electronic device and method can be implemented in other ways. For example, the device / electronic device embodiments described above are merely illustrative. For example, the division of modules or units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed couplings or direct couplings or communication connections to each other can be through some interfaces, and the indirect couplings or communication connections of the devices or units can be in an electrical, mechanical or other forms.

[0084] The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they can be located in one place, or distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0085] In addition, the functional units in the various embodiments of the present application can be integrated into one processing unit, or each unit can exist physically alone, or two or more units can be integrated into one unit. The above-mentioned integrated units can be implemented in the form of hardware or in the form of software functional units.

[0086] When the integrated module / unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, to implement all or part of the processes in the above-described embodiment methods of this application, it can also be completed by instructing relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium. When the computer program is executed by a processor, the steps of the above various method embodiments can be implemented. Among them, the computer program includes computer program code, and the computer program code can be in the form of source code, object code, executable file, or some intermediate form, etc. The computer-readable medium can include: any entity or device capable of carrying computer program code, recording medium, USB flash drive, mobile hard disk, magnetic disk, optical disk, computer memory, ROM, RAM, electrical carrier signal, telecommunication signal, and software distribution medium, etc. It should be noted that the content included in the computer-readable medium can be appropriately increased or decreased according to the requirements of legislation and patent practice within the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, the computer-readable medium does not include electrical carrier signals and telecommunication signals.

[0087] The above are only the preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent replacements, and improvements made within the spirit and principle of this application shall be included within the protection scope of this application.

Claims

1. A DToF-based measurement system, characterized in that, it includes: a transmitter, a collector, and a control and processing circuit, the transmitter is configured to emit an optical signal towards the target; the collector is configured to actuate pixels under the control of the control and processing circuit to receive at least part of the optical signal reflected back by the target and generate measurement data; the control and processing circuit is configured to determine the number of pixels that cause a response in the actuated pixels within a given time period, use the number as the confidence level of the measurement data, and use the confidence level as a reference quantity for subsequent judgment of the influence of the measurement data on the result, so as to avoid the influence of invalid measurement information on the final measurement result; wherein, the given time period is a first preset duration time period starting from the time point when the first pixel responds, or the given time period is a second preset duration time period starting from the time when the optical signal is emitted.

2. The DToF-based measurement system according to claim 1, characterized in that, the measurement data includes histogram data; the actuated pixels output photon signals to a readout circuit in response to the incidence of photons, and the readout circuit is configured to generate the histogram data according to the photon signals.

3. The DToF-based measurement system according to claim 2, characterized in that, the control and processing circuit calculates the distance information of the target only according to the histogram data with the confidence level greater than or equal to a preset threshold.

4. The DToF-based measurement system according to claim 1, characterized in that, the measurement data includes the distance information of the target; the control and processing circuit is configured to calculate the distance information of the target according to the histogram data corresponding to the first pixel that causes a response among the actuated pixels.

5. The DToF-based measurement system according to claim 4, characterized in that, the control and processing circuit is further configured to use the distance information with the confidence level greater than or equal to a preset threshold as valid distance information.

6. A DToF-based measurement method, characterized in that, it includes: controlling a transmitter to emit an optical signal towards a target; synchronously actuating the pixels of a collector to receive at least part of the optical signal reflected back by the target and generate measurement data; determining the number of pixels that cause a response in the actuated pixels within a given time period, using the number as the confidence level of the measurement data, and using the confidence level as a reference quantity for subsequent judgment of the influence of the measurement data on the result, so as to avoid the influence of invalid measurement information on the final measurement result; wherein, the given time period is a first preset duration time period starting from the time point when the first pixel responds, or the given time period is a second preset duration time period starting from the time when the optical signal is emitted.

7. The DToF-based measurement method according to claim 6, characterized in that, the measurement data includes histogram data; the actuated pixels output photon signals to a readout circuit in response to the incidence of photons, and the readout circuit is configured to generate the histogram data according to the photon signals; The generated measurement data includes: calculating the distance information of the target object only based on the histogram data with a confidence level greater than or equal to a preset threshold.

8. The DToF-based measurement method according to claim 7, wherein, the measurement data includes the distance information of the target object; the generation of the measurement data includes: calculating the distance information of the target object according to the histogram data corresponding to the first pixel that causes a response among the actuated pixels; the measurement method further includes: using the distance information with a confidence level greater than or equal to a preset threshold as valid distance information.

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