WO2023279756A1

WO2023279756A1 - Distance measurement system, and method, apparatus and device for determining relative precision thereof

Info

Publication number: WO2023279756A1
Application number: PCT/CN2022/080529
Authority: WO
Inventors: 马宣; 王兆民; 武万多; 何燃; 黄源浩; 肖振中; 李威
Original assignee: 奥比中光科技集团股份有限公司
Priority date: 2021-07-07
Filing date: 2022-03-13
Publication date: 2023-01-12
Also published as: CN115657056A

Abstract

A distance measurement system, and a method, apparatus (4) and device (5) for determining the relative precision thereof. The method comprises: acquiring the number of ambient photons and the number of signal photons, wherein the number of signal photons is the number of photons of electrical signals output after a collector (12) collects optical signals reflected by an object to be measured (20) (S101); calculating relative precision according to the number of ambient photons, the number of signal photons, and a preset relative precision calculation rule (S102), wherein the preset relative precision calculation rule is obtained according to the following steps: acquiring the number of historical ambient photons, the number of historical signal photons, and acquiring relative precision of distance measurement corresponding to the number of historical ambient photons and the number of historical signal photons (S103); and constructing a fitting function according to the number of historical ambient photons, the number of historical signal photons, and the relative precision of distance measurement to obtain a preset relative precision calculation rule (S104). According to the method, the number of signal photons and the number of ambient photons are extracted in real time in a single image frame, and the relative precision is calculated in real time for a single frame, so that the performance determination and exclusion of the distance measurement result of the distance measurement system can be performed in real time, and only 3D points having less noise are retained in output depth data, thereby improving the overall 3D point cloud effect.

Description

A distance measurement system and its relative accuracy determination method, device and equipment

This application claims the priority of the Chinese patent application submitted to the China Patent Office on July 7, 2021 with the application number 202110769043.6 and the title of the invention is "a distance measurement system and its relative accuracy determination method, device, and equipment". The entire contents are incorporated by reference in this application.

technical field

The invention relates to the field of optical technology, in particular to a distance measurement system and a method, device and equipment for determining its relative accuracy.

Background technique

Relative accuracy is an important index when the distance measurement system performs distance measurement. The relative accuracy can feedback the size of the noise of the 3D surface measurement of the measured object. When the relative accuracy is relatively high, the restored 3D point cloud of the surface of the measured object is relatively smooth and the noise is small. When the relative accuracy is low, that is, the 3D points on the surface of the measured object fluctuate greatly, they should be considered as invalid points and need to be excluded.

In the existing technology, when obtaining relative accuracy, it is necessary to obtain multi-frame 3D point cloud data in advance for calculation, and it is impossible to obtain relative accuracy in real time in a single frame, and it is also impossible to judge whether certain points in a single frame image have low relative accuracy, The fluctuation value is large, and it is impossible to exclude the points with low relative accuracy and large fluctuation value in real time.

Contents of the invention

In order to overcome the problems existing in the prior art, embodiments of the present invention provide a distance measurement system and a method, device, and equipment for determining its relative accuracy.

In order to achieve the above object, the technical solution of the embodiment of the present invention is achieved in this way:

Embodiment 1 technical scheme of the present invention is:

A distance measurement system, comprising: a transmitter, a collector, and a processing circuit;

the transmitter configured to emit a signal beam;

The collector includes a pixel unit and a readout circuit, the pixel unit includes a plurality of pixels, and the pixels are used to respond to a single photon in the reflected light beam and output a photon signal; the readout circuit is used for receiving the photon signal for processing and outputting a histogram;

The processing circuit is connected with the emitter and the collector, and is used to receive the histogram to obtain the number of environmental photons and the number of signal photons, and to obtain the number of photons of the environment and the number of signal photons according to the number of photons of the environment, the number of signal photons and the preset relative The accuracy calculation rule calculates the relative accuracy; wherein, the number of signal photons is the photons in the signal beam emitted by the emitter collected by the collector;

Wherein, the preset relative accuracy calculation rule is obtained according to the following steps:

Obtain the number of historical environmental photons, the number of historical signal photons, and obtain the relative accuracy of ranging corresponding to the number of historical environmental photons and historical signal photons;

A fitting function is constructed according to the historical environment photon number, the historical signal photon number and the ranging relative accuracy to obtain a preset relative accuracy calculation rule.

Further, the processing circuit is also used to calculate the distance value of the object to be measured, and judge whether the relative accuracy of the distance value exceeds a preset relative accuracy threshold, and if it exceeds the preset relative accuracy threshold, mask the distance value.

Further, the preset relative accuracy calculation rule is a function model, and the function model is:

Among them, C _s is the number of signal photons; C _n is the number of environmental photons; a, b, c, d are all parameters; R is the relative accuracy.

Another technical solution of the embodiment of the present invention is:

A method for determining the relative accuracy of a distance measurement system, comprising:

Obtaining the number of environmental photons and the number of signal photons; wherein, the number of signal photons is an electrical signal that the collector collects the light signal reflected by the object to be measured and outputs;

calculating relative accuracy according to the number of ambient photons, the number of signal photons, and a preset relative accuracy calculation rule;

Further, it also includes:

calculating the resolution according to the number of ambient photons, the number of signal photons and a preset resolution calculation rule;

The relative accuracy of the distance measurement system is calculated from the resolution.

Further, said obtaining the relative distance measurement accuracy corresponding to the number of historical environmental photons and the number of historical signal photons includes:

Obtain target distance measurement value, target actual distance value and target distance measurement average value;

Calculate the relative distance measurement accuracy according to the target distance measurement value, the target actual distance value and the target distance measurement average value.

Another technical solution of the embodiment of the present invention is:

A device for determining the relative accuracy of a distance measurement system, comprising:

The first acquisition unit is used to acquire the number of environmental photons and the number of signal photons; wherein, the number of signal photons is an electrical signal that the collector collects the light signal reflected by the object to be measured and outputs;

A first processing unit, configured to calculate relative accuracy according to the number of ambient photons, the number of signal photons, and a preset relative accuracy calculation rule;

Further, the first processing unit is also used for:

Another technical solution of the embodiment of the present invention is:

A device for determining the relative accuracy of a distance measurement system, comprising a memory, a processor, and a computer program stored in the memory and operable on the processor, the aforementioned embodiments are realized when the processor executes the computer program The method for determining the relative accuracy of the distance measuring system described in the technical solution.

Compared with the prior art, the present invention extracts the number of signal photons and the number of environmental photons in a single frame image in real time, calculates the relative accuracy with a single frame in real time, and can perform the performance judgment and elimination of the distance measurement result of the DTOF distance measurement system in real time, Only 3D points with less noise are retained in the output depth data, thereby improving the overall 3D point cloud effect.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention.

For better understanding and implementation, the present invention will be described in detail below in conjunction with the accompanying drawings.

Description of drawings

Fig. 1 is a schematic diagram of a distance measuring system shown in an exemplary embodiment of the present invention;

Fig. 2 is a schematic flowchart of a method for determining the relative accuracy of a distance measurement system shown in an exemplary embodiment of the present invention;

Fig. 3 is a schematic flowchart of steps S103-S104 in the method for determining the relative accuracy of the distance measurement system shown in an exemplary embodiment of the present invention;

Fig. 4 is a schematic structural diagram of a device for determining the relative accuracy of a distance measurement system shown in an exemplary embodiment of the present invention;

Fig. 5 is a schematic diagram of a device for determining the relative accuracy of a distance measurement system provided by an exemplary embodiment of the present invention.

detailed description

Reference will now be made in detail to the exemplary embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, the same numerals in different drawings refer to the same or similar elements unless otherwise indicated. The implementations described in the following exemplary examples do not represent all implementations consistent with the present invention. Rather, they are merely examples of apparatuses and methods consistent with aspects of the invention as recited in the appended claims.

The terminology used in the present invention is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used herein and in the appended claims, the singular forms "a", "the", and "the" are intended to include the plural forms as well, unless the context clearly dictates otherwise. It should also be understood that the term "and/or" as used herein refers to and includes any and all possible combinations of one or more of the associated listed items.

Please refer to FIG. 1. FIG. 1 is a schematic diagram showing a distance measurement system according to an exemplary embodiment of the present invention. The distance measurement system includes: a transmitter, a collector, and a processing circuit;

a transmitter 11 configured to emit a signal beam;

The collector 12 includes a pixel unit and a readout circuit, the pixel unit includes a plurality of pixels, and the pixels are used to respond to a single photon in the light beam reflected back by the measured object and output a photon signal; the readout The output circuit is used to receive the photon signal for processing and output a histogram;

The processing circuit 13 is connected with the emitter and the collector, and is used to obtain the number of ambient photons and the number of signal photons, and calculate the relative accuracy according to the number of ambient photons, the number of signal photons and the preset relative accuracy calculation rule ; Wherein, the number of signal photons is the electrical signal that the collector collects the light signal reflected by the object to be measured and outputs;

Specifically, the transmitter 11 is used to transmit the signal beam 30 to the object to be measured 20, and the reflected light signal 40 reflected by the object to be measured is received by the collector; wherein, the transmitter 11 and the collector 12 can be arranged on the substrate, specifically can be set on the same substrate or on different substrates.

The collector 12 includes a pixel unit 121, a filter unit 123 and a receiving optical element 122; wherein the receiving optical element 122 is used to image the speckle beam reflected by the object to be measured onto the pixel unit 121; the filter unit 123 is used to suppress different Background light noise in the rest of the light source wavelength; the pixel unit 121 can be a pixel composed of a charge coupled device (CCD), a complementary metal oxide semiconductor (CMOS), an avalanche diode (AD), a single photon avalanche diode (SPAD), etc. Array, the size of the array represents the resolution of the depth camera, such as 320x240, etc. Generally, the pixel unit 121 is connected to a readout circuit composed of one or more of signal amplifiers, time-to-digital converters (TDC), digital-to-analog converters (ADC) and other devices (not shown in the figure). . These circuits can be integrated with the pixel unit 121 as part of the collector 12 or as a part of the processing circuit.

In an optional embodiment, the pixel unit 121 includes at least one pixel, which is a single photon detector, such as a SPAD, and each pixel responds to a single photon in the reflected light beam and outputs an indication of the received photon in each The photon signal corresponding to the arrival time at the SPAD, the readout circuit receives the photon signal and performs signal processing, and the number of collected photons is counted to form continuous time bins, and these time bins are connected together to form a statistical histogram, which is used to reproduce the reflection of the beam sequentially.

The processing circuit 13 receives the histogram and performs processing to calculate the time-of-flight of the signal beam from transmission to reception, for example, using peak matching and filter detection to identify the time-of-flight of the reflected beam from transmission to reception. In some embodiments, the processing circuit 13 includes a readout circuit (not shown in the figure) composed of one or more of a signal amplifier, a time-to-digital converter (TDC), a digital-to-analog converter (ADC) and other devices. These circuits can be integrated with the pixels, or can be part of the processing circuit 13 .

The processing circuit 13 may be an independent dedicated circuit, such as a dedicated SOC chip, FPGA chip, ASIC chip, etc. composed of a CPU, memory, bus, etc., or may include a general-purpose processing circuit.

In an optional embodiment, the processing circuit is also used to calculate the distance value of the object to be measured, and determine whether the relative accuracy of the distance value exceeds a preset relative accuracy threshold, and if it exceeds the preset relative accuracy threshold, block The distance value.

An embodiment of the method for determining the relative accuracy of the distance measurement system will be described in detail later, and the processing circuit calculates the relative accuracy of the distance measurement system according to the determination method.

Please refer to Fig. 2, Fig. 2 is a schematic flow chart of a method for determining the relative accuracy of the distance measurement system shown in an exemplary embodiment of the present invention, the method is executed by a device for determining the relative accuracy of the distance measurement system (hereinafter referred to as the device), including the following step:

S101: Obtain the number of ambient photons and the number of signal photons; wherein, the number of signal photons is the electrical signal that the collector collects the light signal reflected by the object under test and outputs it.

It should be noted that, in this embodiment, the distance measurement system is a DTOF distance measurement system. The collector of the DTOF ranging system includes a pixel unit and a readout circuit. The pixel unit includes a plurality of pixels; the pixel is a single photon detector, such as a SPAD, and each pixel responds to a single photon in the reflected beam and outputs a photon signal , the electric signal is a photon signal indicating the corresponding arrival time of the received photon at each SPAD, and the readout circuit includes a TDC circuit and a histogram circuit. Among them, the TDC circuit is used to receive and calculate the time interval of the photon signal, and convert the time interval into a time code; the histogram circuit counts according to the time code output by the TDC circuit to draw a histogram. The number of ambient photons and the number of signal photons are calculated according to the histogram output by the histogram circuit.

During the ranging process, when the collector is triggered to collect photons, due to the influence of the ambient light signal, there are a large number of ambient photons in the histogram, showing a uniform distribution in all time bins. Therefore, before calculating the number of signal photons, it is necessary to first determine the mean value of the number of ambient photons in the histogram, that is, the number of collected ambient photons in each time bin. Specifically, select n time intervals away from the pulse position in the histogram, calculate the average value of the photon count value in the n time intervals and record it as the average value of the ambient photon number, and n is an arbitrary integer.

According to the pulse peak position and pulse width, the pulse area is intercepted from the histogram to calculate the number of signal photons. Generally, the size of the time interval in the histogram is tens to tens of picoseconds, and the photon signal of a pulsed beam emitted by the transmitter is correspondingly distributed in multiple consecutive time intervals in the histogram, according to the pulse width of the pulsed beam And the size of the time interval in the histogram, it can be determined that the photon signal of a pulse is in a plurality of consecutive time intervals in an interval corresponding to the distribution in the histogram, and the total number of photon counts in this area is calculated minus the number of photons in this interval. The number of photons in the environment can be used to determine the number of photons in the signal. For example, the interval includes m time intervals, then the number of signal photons

C _nm is the total number of photon counts in this interval,

is the mean value of ambient photon number.

Further, the number of ambient photons is calculated according to the average value of the number of ambient photons, the number of ambient photons is the number of ambient photons collected synchronously when the collector collects the photons in the signal beam reflected by the measured object, that is, the corresponding distribution of a pulse in the histogram The number of ambient photons included in an interval, where

is the number of ambient photons.

In some other embodiments, other methods may also be used to calculate the number of ambient photons and the number of signal photons, which are not specifically limited in the present invention.

S102: Calculate relative accuracy according to the number of ambient photons, the number of signal photons, and a preset relative accuracy calculation rule.

The device calculates the relative accuracy according to the number of ambient photons, the number of signal photons and the preset relative accuracy calculation rules. Pre-stored preset relative accuracy calculation rules in the device, that is: the corresponding relationship between the number of ambient photons, the number of signal photons and the relative accuracy, calculated according to the corresponding relationship between the number of ambient photons, the number of signal photons and the relative accuracy relative accuracy.

Wherein, in this embodiment, there is no specific limitation on the preset relative accuracy calculation rule. When the preset relative accuracy calculation rule is a function model, it can be a function model in various forms. For example, the preset relative accuracy calculation rule can be The following function model:

The preset relative accuracy calculation rule can also be the following function model:

Among them, C _s is the number of signal photons; C _n is the number of environmental photons; a, b, c, d are all parameters; f is the focal length of the lens of the collector.

In an optional embodiment, the resolution can also be calculated first, and the device calculates the resolution according to the number of ambient photons, the number of signal photons and the preset resolution calculation rules. Then calculate the relative accuracy of the distance measurement system according to the resolution. Specifically, the device can calculate the relative accuracy of the distance measurement system based on the resolution and the preset law of three standard deviations. According to the law of triple standard deviation, the relationship between resolution and relative accuracy is:

R＝1/3×E _Resolution

Among them, R is the relative accuracy, and E _Resolution is the resolution.

Among them, in order to obtain accurate calculation results of relative precision, a function model with preset relative precision calculation rules can be obtained by fitting or training the sampled data. Before calculation, a fitting function can be constructed to fit a function model for relative accuracy calculation. Before step S102, steps S103-S104 can also be included, as shown in Figure 3. Steps S103-S104 are specifically as follows:

S103: Acquiring the number of historical environmental photons, the number of historical signal photons, and the relative distance measurement accuracy corresponding to the number of historical environmental photons and the number of historical signal photons.

The device obtains the number of historical environmental photons and the number of historical signal photons, and obtains the resolution corresponding to the historical number of environmental photons and the number of historical signal photons. The number of historical environmental photons, the number of historical signal photons, and the relative accuracy of ranging corresponding to the number of historical environmental photons and historical signal photons can be used as a set of calibration data, and the preset relative accuracy can be obtained by obtaining multiple sets of calibration data for fitting. Calculation Rules. It should be noted that the historical ambient photon numbers and historical signal photon numbers here are just such defined names, which represent the multi-sampled ambient photon numbers and sampled signal photon numbers, rather than past and historical meanings.

Specifically, simulation experiments can be used to obtain the number of historical environmental photons and historical signal photons, and the relative accuracy of distance measurement can be affected by changing the beam incident angle cosθ, ambient light intensity I _AL , reflectivity, distance L of the object to be measured, etc. A set of calibration data is obtained by continuous measurement of each point multiple times.

In an optional embodiment, the distance measurement relative accuracy is obtained by a pre-calibration method, and the device calculates the distance measurement relative accuracy by obtaining the target distance measurement value, the target actual distance value, and the target distance measurement average value. Specifically, it is assumed that the target point is set at a distance of L _m from the distance measurement system, (m=1, 2, 3..., M), for example, when m=1, set L ₁ =1m when m=1, When m=2, set L ₂ =1.1m, when m=3, set L ₃ =1.3m, . . . Among them, set L ₁ =1m, L ₁ is the actual distance value of the target, measure n times continuously to obtain the target distance measurement value l ₁ -ln, and obtain the environmental photon number C _nn and the signal photon number C _sn in each measurement process. Among them, calculate the standard deviation between the target distance measurement value of n times and the target actual distance value and record it as the relative distance measurement accuracy, and calculate the average value of the historical environmental photon number and historical signal photon number of _n times of measurement, and obtain the target point at L1 A set of calibration data. Among them, the process of obtaining the calculation relative accuracy after n measurements is as follows:

According to the calculation formula of the distance of the TOF distance measurement system:

Wherein, c is the speed of light, which is about 3×10 ⁸ m/s, and t _i is the time of flight of light measured for the ith time. Then calculate the target distance measurement value d _i of the i-th measurement in consecutive n measurements, and the target distance measurement average value of the n measurements

Then the resolution of the distance measurement system is:

Among them, _di represents the distance value obtained from the i-th measurement, and the number of tests ranges from 1 to n, a total of n times.

represents the average value of n measurements,

It can be expressed as:

Generally speaking, according to the law of triple standard deviation, the relationship between resolution and relative accuracy of ranging is,

R＝1/3×E _Resolution

Then, the relative accuracy of distance measurement is calculated after n times of sampling, and a set of calibration data can be obtained by calculating the average value of n times of historical environmental photon numbers and historical signal photon numbers.

In the continuous sampling process, parameters such as incident angle, ambient light intensity or reflectivity can be adjusted, and multiple sets of calibration data can be obtained by repeating the above sampling process. It is understandable that only one of the influencing parameters can be adjusted or multiple parameters can be adjusted at the same time. The size of the parameters can be adjusted randomly by using the mode of generating random numbers, or the size of the parameters can be adjusted according to certain rules, such as from small to large or The adjustment mode from large to small, the specific adjustment method is not limited in this application.

S104: Construct a fitting function according to the historical environmental photon count, the historical signal photon count, and the ranging relative accuracy to obtain a preset relative accuracy calculation rule.

The device builds a fitting function based on the number of historical environmental photons, the number of historical signal photons, and the relative accuracy of distance measurement. Commonly used fitting methods include the least squares curve fitting method, etc. In MATLAB, polyfit can also be used to fit polynomials to obtain a fitting After the function, you can get the preset relative accuracy calculation rules.

The present invention extracts the number of signal photons and the number of environmental photons in a single frame image in real time, calculates the relative accuracy with a single frame in real time, can perform the performance judgment and exclusion of the ranging result of the DTOF distance measuring system in real time, and realizes the accuracy of the output depth data. Only keep 3D points with less noise, thereby improving the overall 3D point cloud effect.

Please refer to FIG. 4 . FIG. 4 is a schematic structural diagram of an apparatus for determining the relative accuracy of a distance measurement system according to an exemplary embodiment of the present invention. The included units are used to execute the steps in the embodiments corresponding to FIG. 2 and FIG. 3 . For details, please refer to the relevant descriptions in the embodiments corresponding to FIG. 2 and FIG. 3 . For ease of description, only the parts related to this embodiment are shown. Referring to Fig. 4, the determining device 4 of the relative accuracy of the distance measurement system comprises:

The first acquisition unit 410 is configured to acquire the number of ambient photons and the number of signal photons; wherein, the number of signal photons is an electrical signal that the collector collects and outputs an optical signal reflected by the object to be measured;

The first processing unit 420 is configured to calculate relative accuracy according to the number of ambient photons, the number of signal photons, and a preset relative accuracy calculation rule;

Further, the first processing unit 420 is also configured to:

Further, the first processing unit 420 is specifically configured to:

The relative accuracy of the distance measuring system is calculated according to the stated resolution and the preset law of three standard deviations.

Further, the device for determining the relative accuracy of the distance measurement system also includes:

The second acquisition unit is used to acquire the number of historical environmental photons, the number of historical signal photons, and the relative distance measurement accuracy corresponding to the number of historical environmental photons and the number of historical signal photons;

The second processing unit is configured to construct a fitting function according to the historical environmental photon number, the historical signal photon number and the relative distance measurement accuracy to obtain a preset relative accuracy calculation rule.

The third obtaining unit is used to obtain the target distance measurement value, the target actual distance value and the target distance measurement average value;

The third acquiring unit is configured to calculate the relative distance measurement accuracy according to the target distance measurement value, the target actual distance value and the target distance measurement average value.

Please refer to FIG. 5 , which is a schematic diagram of a device for determining the relative accuracy of a distance measurement system provided by an exemplary embodiment of the present invention. As shown in Fig. 5, the determining device 5 of the relative accuracy of the distance measurement system of this embodiment includes: a processor 50, a memory 51, and a computer program 52 stored in the memory 51 and operable on the processor 50, An example is the procedure for determining the relative accuracy of distance measuring systems. When the processor 50 executes the computer program 52, it realizes the steps in the above embodiments of the method for determining the relative accuracy of each distance measurement system, such as steps S101 to S102 shown in FIG. 2 . Alternatively, when the processor 50 executes the computer program 52, it realizes the functions of the modules/units in the above-mentioned device embodiments, such as the functions of the units 410 to 420 shown in FIG. 4 .

Exemplarily, the computer program 52 can be divided into one or more modules/units, and the one or more modules/units are stored in the memory 51 and executed by the processor 50 to complete this invention. The one or more modules/units may be a series of computer program instruction segments capable of completing specific functions, and the instruction segments are used to describe the execution process of the computer program 52 in the device 5 for determining the relative accuracy of the distance measurement system . For example, the computer program 52 can be divided into a first acquisition module and a first processing module, and the functions of each module are as follows:

The first acquisition module is used to acquire the number of environmental photons and the number of signal photons; wherein, the number of signal photons is an electrical signal that the collector collects and outputs an optical signal reflected by the object to be measured;

The first processing module is configured to calculate relative accuracy according to the number of ambient photons, the number of signal photons and a preset relative accuracy calculation rule.

The device 5 for determining the relative accuracy of the distance measurement system may include, but not limited to, a processor 50 and a memory 51 . Those skilled in the art can understand that Fig. 5 is only an example of the determining device 5 for the relative accuracy of the distance measuring system, and does not constitute a limitation to the determining device 5 for the relative accuracy of the distance measuring system, and may include more or less than shown in the figure. Components, or a combination of certain components, or different components, for example, the device for determining the relative accuracy of the distance measurement system 5 may also include input and output devices, network access devices, buses, and the like.

The so-called processor 50 can be a central processing unit (Central Processing Unit, CPU), and can also be other general-purpose processors, digital signal processors (Digital Signal Processor, DSP), application specific integrated circuits (Application Specific Integrated Circuit, ASIC), Off-the-shelf programmable gate array (Field-Programmable Gate Array, FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor, or the processor may be any conventional processor, or the like.

The memory 51 may be an internal storage unit of the device 5 for determining the relative accuracy of the distance measurement system, for example, a hard disk or a memory of the device 5 for determining the relative accuracy of the distance measurement system. The memory 51 can also be an external storage device of the determining device 5 of the relative accuracy of the distance measuring system, such as a plug-in hard disk equipped on the determining device 5 of the relative accuracy of the distance measuring system, a smart memory card (Smart Media Card , SMC), Secure Digital (Secure Digital, SD) card, Flash Card (Flash Card), etc. Further, the memory 51 may also include both an internal storage unit of the device 5 for determining the relative accuracy of the distance measurement system and an external storage device. The memory 51 is used to store the computer program and other programs and data required by the device for determining the relative accuracy of the distance measuring system. The memory 51 can also be used to temporarily store data that has been output or will be output.

Those skilled in the art can clearly understand that for the convenience and brevity of description, only the division of the above-mentioned functional units and modules is used for illustration. In practical applications, the above-mentioned functions can be assigned to different functional units, Completion of modules means that the internal structure of the device is divided into different functional units or modules to complete all or part of the functions described above. Each functional unit and module in the embodiment may be integrated into one processing unit, or each unit may exist separately physically, or two or more units may be integrated into one unit, and the above-mentioned integrated units may adopt hardware It can also be implemented in the form of software functional units. In addition, the specific names of the functional units and modules are only for the convenience of distinguishing each other, and are not used to limit the protection scope of the present application. For the specific working process of the units and modules in the above system, reference may be made to the corresponding process in the foregoing method embodiments, and details will not be repeated here.

In the above-mentioned embodiments, the descriptions of each embodiment have their own emphases, and for parts that are not detailed or recorded in a certain embodiment, refer to the relevant descriptions of other embodiments.

Those skilled in the art can appreciate that the units and algorithm steps of the examples described in conjunction 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 by hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art may use different methods to implement the described functions for each specific application, but such implementation should not be regarded as exceeding the scope of the present invention.

In the embodiments provided in the present invention, it should be understood that the disclosed apparatus/terminal equipment and method may be implemented in other ways. For example, the device/terminal device embodiments described above are only illustrative. For example, the division of the modules or units is only a logical function division. In actual implementation, there may be other division methods, such as multiple units Or components may be combined or may be integrated into another system, or some features may be omitted, or not implemented. In another point, the mutual coupling or direct coupling or communication connection shown or discussed may be through some interfaces, and the indirect coupling or communication connection of devices or units may be in electrical, mechanical or other forms.

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

In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, each unit may exist separately physically, or two or more units may 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.

If the integrated module/unit is realized in the form of a software function unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the present invention realizes all or part of the processes in the methods of the above embodiments, and can also be completed by instructing related hardware through a computer program. The computer program can be stored in a computer-readable storage medium, and the computer When the program is executed by the processor, the steps in the above-mentioned various method embodiments can be realized. Wherein, the computer program includes computer program code, and the computer program code may be in the form of source code, object code, executable file or some intermediate form. The computer-readable medium may include: any entity or device capable of carrying the computer program code, a recording medium, a USB flash drive, a removable hard disk, a magnetic disk, an optical disk, a computer memory, and a read-only memory (ROM, Read-Only Memory) , Random Access Memory (RAM, Random Access Memory), electrical carrier signal, telecommunication signal and software distribution medium, etc. It should be noted that the content contained in the computer-readable medium may be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, computer-readable media Excludes electrical carrier signals and telecommunication signals. The present invention is not limited to the above-mentioned embodiments, if the various changes or deformations of the present invention do not depart from the spirit and scope of the present invention, if these changes and deformations belong to the claims of the present invention and the equivalent technical scope, then the present invention is also It is intended that such modifications and variations are included.

Claims

A distance measurement system, characterized in that it includes: a transmitter, a collector, and a processing circuit;

the transmitter configured to emit a signal beam;

The collector includes a pixel unit and a readout circuit, the pixel unit includes a plurality of pixels, and the pixels are used to respond to a single photon in the reflected light beam and output a photon signal; the readout circuit is used for receiving the photon signal for processing and outputting a histogram;

The processing circuit is connected with the emitter and the collector, and is used to receive the histogram to obtain the number of environmental photons and the number of signal photons, and to obtain the number of photons of the environment and the number of signal photons according to the number of photons of the environment, the number of signal photons and the preset relative The accuracy calculation rule calculates the relative accuracy; wherein, the number of signal photons is the photons in the signal beam emitted by the emitter collected by the collector;

Wherein, the preset relative accuracy calculation rule is obtained according to the following steps:

Obtain the number of historical environmental photons, the number of historical signal photons, and obtain the relative accuracy of ranging corresponding to the number of historical environmental photons and historical signal photons;

A fitting function is constructed according to the historical environment photon number, the historical signal photon number and the ranging relative accuracy to obtain a preset relative accuracy calculation rule.
The distance measurement system according to claim 1, wherein the processing circuit is also used to calculate the distance value of the object to be measured, and judge whether the relative accuracy of the distance value exceeds a preset relative accuracy threshold, if the relative accuracy exceeds the preset If the relative accuracy threshold is set, the distance value is masked.
The distance measurement system according to claim 1, wherein the preset relative accuracy calculation rule is a function model, and the function model is:

Among them, C s is the number of signal photons; C n is the number of environmental photons; a, b, c, d are all parameters; R is the relative accuracy.
The distance measurement system according to claim 2, wherein the preset relative accuracy calculation rule is a function model, and the function model is:

Among them, C s is the number of signal photons; C n is the number of environmental photons; a, b, c, d are all parameters; R is the relative accuracy.
A method for determining the relative accuracy of a distance measurement system, comprising:

Obtaining the number of environmental photons and the number of signal photons; wherein, the number of signal photons is an electrical signal that the collector collects the light signal reflected by the object to be measured and outputs;

calculating relative accuracy according to the number of ambient photons, the number of signal photons, and a preset relative accuracy calculation rule;

Wherein, the preset relative accuracy calculation rule is obtained according to the following steps:

Obtain the number of historical environmental photons, the number of historical signal photons, and obtain the relative accuracy of ranging corresponding to the number of historical environmental photons and historical signal photons;

A fitting function is constructed according to the historical environment photon number, the historical signal photon number and the ranging relative accuracy to obtain a preset relative accuracy calculation rule.
The method for determining the relative accuracy of a distance measurement system according to claim 5, wherein the preset relative accuracy calculation rule is a function model, and the function model is:

Among them, C s is the number of signal photons; C n is the number of environmental photons; a, b, c, d are all parameters; R is the relative accuracy.
The method for determining the relative accuracy of the distance measurement system according to claim 5, further comprising:

calculating the resolution according to the number of ambient photons, the number of signal photons and a preset resolution calculation rule;

The relative accuracy of the distance measurement system is calculated from the resolution.
The method for determining the relative accuracy of the distance measurement system according to claim 5, wherein said obtaining the relative accuracy of distance measurement corresponding to the number of historical environmental photons and the number of historical signal photons comprises:

Obtain target distance measurement value, target actual distance value and target distance measurement average value;

Calculate the relative distance measurement accuracy according to the target distance measurement value, the target actual distance value and the target distance measurement average value.
A device for determining the relative accuracy of a distance measurement system, characterized in that it includes:

The first acquisition unit is used to acquire the number of environmental photons and the number of signal photons; wherein, the number of signal photons is an electrical signal that the collector collects and outputs an optical signal reflected by the object to be measured;

A first processing unit, configured to calculate relative accuracy according to the number of ambient photons, the number of signal photons, and a preset relative accuracy calculation rule;

Wherein, the preset relative accuracy calculation rule is obtained according to the following steps:

Obtain the number of historical environmental photons, the number of historical signal photons, and obtain the relative accuracy of ranging corresponding to the number of historical environmental photons and historical signal photons;

A fitting function is constructed according to the historical environment photon number, the historical signal photon number and the ranging relative accuracy to obtain a preset relative accuracy calculation rule.
The device for determining the relative accuracy of the distance measurement system according to claim 9, wherein the first processing unit is also used for:

calculating the resolution according to the number of ambient photons, the number of signal photons and a preset resolution calculation rule;

The relative accuracy of the distance measurement system is calculated from the resolution.
A device for determining the relative accuracy of a distance measurement system, comprising a memory, a processor, and a computer program stored in the memory and operable on the processor, wherein when the processor executes the computer program A method for determining the relative accuracy of a distance measurement system is realized; the method for determining the relative accuracy of the distance measurement system includes:

Obtaining the number of environmental photons and the number of signal photons; wherein, the number of signal photons is an electrical signal that the collector collects the light signal reflected by the object to be measured and outputs;

calculating relative accuracy according to the number of ambient photons, the number of signal photons, and a preset relative accuracy calculation rule;

Wherein, the preset relative accuracy calculation rule is obtained according to the following steps:

Obtain the number of historical environmental photons, the number of historical signal photons, and obtain the relative accuracy of ranging corresponding to the number of historical environmental photons and historical signal photons;

A fitting function is constructed according to the historical environment photon number, the historical signal photon number and the ranging relative accuracy to obtain a preset relative accuracy calculation rule.
The device for determining the relative accuracy of the distance measurement system according to claim 11, wherein the preset relative accuracy calculation rule is a function model, and the function model is:

Among them, C s is the number of signal photons; C n is the number of environmental photons; a, b, c, d are all parameters; R is the relative accuracy.
The device for determining the relative accuracy of the distance measurement system according to claim 11, wherein the method for determining the relative accuracy of the distance measurement system further comprises:

calculating the resolution according to the number of ambient photons, the number of signal photons and a preset resolution calculation rule;

The relative accuracy of the distance measurement system is calculated from the resolution.
According to the device for determining the relative accuracy of the distance measurement system according to claim 11, the acquisition of the relative accuracy of distance measurement corresponding to the number of historical environmental photons and the number of historical signal photons comprises:

Obtain target distance measurement value, target actual distance value and target distance measurement average value;

Calculate the relative distance measurement accuracy according to the target distance measurement value, the target actual distance value and the target distance measurement average value.