A detection system based on dToF and light source adjustment method thereof

Abstract

The present application relates to the field of optical detection technology, and in particular to a detection system based on dToF and a light source adjustment method thereof, the light source adjustment method comprising: controlling a working light source in a transmitter to emit a spot light beam toward a target object according to a first light intensity; synchronously activating a working pixel in a collector to receive at least a portion of the spot light beam reflected back by the target object and generate detection parameters of a photon detection event, wherein the photon detection event is an event in which the working pixel outputs a photon detection signal in response to the incidence of a photon; and adjusting the first light intensity of the working light source according to the detection parameters, wherein the detection parameters include: the grayscale value of the working pixel, the maximum value or average value of the corresponding values of each time interval in the histogram. The embodiment of the present application can adjust the luminous intensity of the transmitting end to match different distances, reflectivities, interference environments, etc., and can save storage resources of the histogram of the receiving end.

Description

Technical Field

[0001] The present application relates to the field of optical detection technology, and in particular to a detection system based on direct time of flight (dToF) and a light source adjustment method thereof. Background Art

[0002] Time of Flight (ToF) technology is a two-way ranging technique that uses the time it takes for a light signal to travel back and forth between a transmitter and a collector to measure the distance to a target. Currently, detection systems based on ToF technology are widely used in consumer electronics, unmanned vehicles, augmented reality (AR), and virtual reality (VR).

[0003] ToF technology can be divided into dToF technology and indirect time-of-flight (iToF) technology. dToF technology measures the flight time of photons in a light beam from emission to reception based on time-correlated single photon counting (TCSPC) technology; iToF technology measures the phase delay of the reflected light beam relative to the emitted light beam, and then calculates the flight time based on the phase delay. dToF technology has the advantages of high signal-to-noise ratio, good sensitivity, and high accuracy, and has received increasing attention.

[0004] When using a detection system based on dToF technology, the light source at the transmitting end usually emits a beam of light with a fixed luminous intensity. This makes it difficult for the detection system to match and obtain better measurement accuracy when the detection environment changes. This shortcoming is particularly evident in different detection environments, such as different target distances, different reflectivities, and different ambient light intensities.

[0005] The disclosure of the above background technology content is only used to assist in understanding the concept and technical solution of this application. It does not necessarily belong to the prior art of this application. In the absence of clear evidence that the above content has been disclosed before the filing date of this application, the above background technology should not be used to evaluate the novelty and creativity of this application. Summary of the Invention

[0006] The purpose of the embodiments of the present application is to provide a dToF-based detection system and a light source adjustment method thereof, aiming to solve one or more technical problems in related technologies.

[0007] To achieve the above-mentioned purpose, in the first aspect, an embodiment of the present application provides a light source adjustment method for a dToF-based detection system, comprising: controlling the working light source in the transmitter to emit a spot light beam toward the target object according to a first light intensity; synchronously activating the working pixels in the collector to receive at least part of the spot light beam reflected back by the target object and generate detection parameters of a photon detection event, wherein the photon detection event is an event in which the working pixel outputs a photon detection signal in response to the incidence of a photon; and adjusting the first light intensity of the working light source according to the detection parameters.

[0008] In some embodiments, the detection parameters include: the grayscale value of the working pixel, and the maximum value or average value of the values corresponding to each time interval in the histogram.

[0009] In some embodiments, the grayscale value of the working pixel is a statistical number of the photon detection event.

[0010] In some embodiments, adjusting the first light intensity of the working light source according to the detection parameters includes: determining a driving current change value of the working light source according to the detection parameters, determining a current driving current according to an initial driving current value and the driving current change value, and controlling the working light source to turn on according to the current driving current, wherein the initial driving current value is the driving current corresponding to the first light intensity.

[0011] In some embodiments, determining the driving current change value of the working light source according to the detection parameter includes: according to the formula ΔI=a(C tg -C n )+b calculates the driving current change value ΔI, where a and b are coefficients, C tg is the target photon number, C n is the detection parameter.

[0012] In some embodiments, the current driving current is determined according to the driving current initial value and the driving current change value, including: according to formula I n =I base +ΔI calculates the current driving current I n , where I base is the initial value of the driving current, and ΔI is the change value of the driving current.

[0013] In the second aspect, an embodiment of the present application provides a dToF-based detection system, comprising: an emitter, a collector, and a control and processing circuit, wherein the emitter is configured to turn on a working light source to emit a spot light beam toward a target object at a first light intensity; the collector is configured to activate a working pixel to receive at least a portion of the spot light beam reflected back by the target object and generate detection parameters of a photon detection event, wherein the photon detection event is an event in which the working pixel outputs a photon detection signal in response to the incidence of a photon; the control and processing circuit is configured to adjust the first light intensity of the working light source according to the detection parameters; wherein the detection parameters include: the grayscale value of the working pixel, the maximum value or average value of the corresponding values of each time interval in the histogram.

[0014] In some embodiments, the collector includes a pixel array consisting of multiple pixels and a readout circuit array consisting of multiple readout circuits. The pixels are connected to the readout circuits in a one-to-one correspondence. The event in which the working pixels output a photon detection signal in response to the incidence of photons is a photon detection event, and the readout circuit is used to generate detection parameters for the photon detection event.

[0015] In some embodiments, the readout circuit includes a counting circuit for counting a statistical number of the photon detection events of the working pixel; and the control and processing circuit is configured to use the statistical number as a detection parameter.

[0016] In some embodiments, the readout circuit includes a TDC circuit and a histogram circuit, the TDC circuit is used to generate a time signal based on the photon detection signal output by the working pixel, and the histogram circuit is used to generate a histogram based on the time signal; the control and processing circuit is configured to use the maximum value of the value corresponding to each time interval in the histogram as the detection parameter, or, is configured to calculate the average value of the value corresponding to each time interval in the histogram as the detection parameter.

[0017] In some embodiments, the control and processing circuit determines the driving current change value of the working light source based on the detection parameters, determines the current driving current based on the driving current initial value and the driving current change value, controls the working light source to turn on according to the current driving current, and the driving current initial value is the driving current corresponding to the first light intensity.

[0018] In a third aspect, an embodiment of the present application provides an electronic device, comprising the dToF-based detection system described in any embodiment of the second aspect, wherein the transmitter and collector of the dToF-based detection system are arranged on the same side of the electronic device body.

[0019] The beneficial effects of the embodiments of the present application are that, when detecting a target object, the luminous intensity of the light source is adjusted according to the detection parameters of the photon detection event, thereby achieving dynamic adjustment of the light source. This allows determining the optimal luminous intensity at the emission end of the detection system, while simultaneously receiving the optimal number of photons at the collection end, thereby achieving precise detection, adapting to different detection environments, and conserving histogram storage resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments or descriptions of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0021] Figure 1 A schematic structural diagram of a dToF-based detection system provided in one embodiment of the present application.

[0022] Figure 2 A schematic diagram of the structure of a collector provided in one embodiment of the present application.

[0023] Figure 3 A schematic diagram of the implementation flow of a light source adjustment method for a dToF-based detection system provided in one embodiment of the present application.

[0024] Figure 4 A schematic diagram of a histogram provided in one embodiment of the present application.

[0025] Figure 5 A schematic structural diagram of an electronic device provided in one embodiment of the present application. DETAILED DESCRIPTION

[0026] In order to make the technical problems, technical solutions and beneficial effects to be solved by this application more clearly understood, this application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0027] References to "one embodiment" or "some embodiments" in this specification mean that one or more embodiments of the present application include a particular feature, structure, or characteristic described in conjunction with that embodiment. Thus, phrases such as "in one embodiment," "in some embodiments," "in other embodiments," and "in yet other embodiments" appearing in various places in this specification do not necessarily refer to the same embodiment, but rather mean "one or more but not all embodiments," unless otherwise specifically emphasized. The terms "including," "comprising," "having," and variations thereof all mean "including but not limited to," unless otherwise specifically emphasized.

[0028] It should be noted that when an element is referred to as being "connected" to another element, it may be directly connected to the other element or indirectly connected to the other element. In addition, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0029] In order to illustrate the technical solution described in this application, specific embodiments are provided below.

[0030] See also Figure 1 , an embodiment of the present application provides a detection system 10 based on dToF. The detection system 10 based on dToF includes a transmitter 11, a collector 12, and a control and processing circuit 13. Among them, the transmitter 11 is used to transmit a transmission light beam 30 to the target area 20, and the transmission light beam 30 is emitted into the space of the target area 20 to illuminate the target object in the space. At least part of the light beam 30 is reflected by the target object to form a reflected light beam 40, and at least part of the reflected light beam 40 is received by the collector 12. The collector 12 receives the reflected light beam 40 and generates detection information; the control and processing circuit 13 is connected to the transmitter 11 and the collector 12 respectively, and synchronizes the trigger signals of the transmitter 11 and the collector 12. The control and processing circuit 13 can obtain the detection information fed back by the collector 12 and perform subsequent processing and control according to the detection information.

[0031] In some embodiments, the emitter 11 includes a light source 111, an emitting optical element 112, and a driver 113, etc. The light source 111 can be a light-emitting diode (LED), a laser diode (LD), an edge emitting laser (EEL), a vertical cavity surface emitting laser (VCSEL), etc., or it can be 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 light beam emitted by the light source 111 can be visible light, infrared light, ultraviolet light, etc.

[0032] The emission optical element 112 receives the emission light beam 30 emitted from the light source 111, shapes it, and projects it onto the target area 20. The emission optical element 112 receives the pulsed light beam from the light source 111 and optically modulates the pulsed light beam, such as by diffraction, refraction, or reflection, and then emits the modulated light beam, such as a focused light beam, a flood light beam, or a structured light beam, toward the target area 20. The emission optical element 112 can be a combination of one or more of a lens, a liquid crystal element, a diffractive optical element, a microlens array, a metasurface optical element, a mask, a reflector, a MEMS galvanometer, and the like.

[0033] In one embodiment, the light source 111 is driven by the driver 113 and controlled by the control and processing circuit 13 to emit a pulse light beam at a certain frequency (or pulse period) and a certain light intensity. The pulse light beam passes through the emitting optical element 112 and is projected onto the target object to form an illumination spot. The frequency can be set according to the measurement distance; the light intensity can be adjusted according to the detection signal.

[0034] In some embodiments, the collector 12 includes a pixel array 121, a filtering unit 122, a receiving optical element 123, and a readout circuit array ( Figure 1 The receiving optical element 123, the filtering unit 122, and the pixel array 121 are sequentially arranged along the propagation path of the optical signal.

[0035] The receiving optical element 123 is used to receive at least a portion of the reflected light beam 40 reflected by the target and direct at least a portion of the reflected light beam 40 to the pixel array 121 to image the target onto the pixel array 121. The filtering unit 122 is used to filter out background light or stray light. For example, it can be a bandpass filter. The pixel array 121 is composed of a plurality of pixels. The pixel array 121 is configured to activate (i.e., actuate) at least a portion of the pixels, i.e., working pixels, under the control of the control and processing circuit 13 to collect at least a portion of the reflected light beam 40 reflected by the target. A working pixel generates a photon detection signal in response to the incidence of a photon, which is referred to as a photon detection event. The readout circuit array is composed of a plurality of readout circuits. The readout circuits are used to receive the photon detection signal of each working pixel and process it to generate a histogram. On the other hand, the readout circuits are used to count the number of photon detection signals output by each working pixel, i.e., to count the number of photon detection events. In one embodiment, the number of photon detection events occurring in any working pixel is the grayscale value of the working pixel. In one embodiment, the pixel array 121 is a SPAD array composed of multiple single-photon avalanche photodiodes (SPADs). Optionally, the SPAD array is an addressable matrix. Generally, the control and processing circuit 13 can interact with the logic components of the SPAD array to select one or more pixels that need to be actuated at any given time, i.e., working pixels. The pixel array 121 is configured to actuate the working pixels under the control of the control and processing circuit 13 for receiving the reflected light beam 40.

[0036] It should be noted that theoretical calculations can be performed in advance based on multiple parameters of the detection system to predict the imaging position of each light source on the pixel array. This allows the working pixel corresponding to the one or more light sources (i.e., working light sources) to be determined. In other words, the working pixel is the predicted imaging position in the pixel array of the spot light beam emitted by the working light source and reflected by the target object.

[0037] Pixel array 121 is connected to a readout circuit array. Specifically, each pixel in pixel array 121 is connected to a corresponding readout circuit. The readout circuit receives and accumulates photon detection signals from the corresponding connected pixel to generate a histogram for the pixel; at the same time, the readout circuit counts the number of photon detection signals from the corresponding connected pixel. In some embodiments, the readout circuit includes one or more devices such as a signal amplifier, a time-to-digital converter (TDC), an analog-to-digital converter (ADC), and a counter.

[0038] In one embodiment, the readout circuit includes a counting circuit, a TDC circuit, and a histogram circuit, such as Figure 2As shown, each pixel in the pixel array is connected to a corresponding counting circuit and a time-determining circuit. The pixel receives photons from a pulsed light signal reflected by a target object and generates corresponding photon detection signals. The counting circuit receives and counts these photon detection signals, i.e., the statistical count. The TDC circuit receives and calculates the time difference of the photon detection signals and can also convert the time difference into a time code. The histogram circuit accumulates the time difference or time code output by the TDC circuit to generate a histogram. The readout circuit can be electrically connected to the control and processing circuit. In some embodiments, the control and processing circuit can receive the histogram, obtain the maximum or average value of the photon counts within each time interval (bin) in the histogram, and adjust the light intensity of the light source based on the maximum or average value. In some embodiments, the control and processing circuit can also receive the statistical count and adjust the light intensity of the light source based on the statistical count. In some embodiments, the control and processing circuit can also receive the histogram, determine the flight time between the emission and reception of the photons based on the histogram, and then calculate the distance information of the target object based on the flight time value.

[0039] Furthermore, in some embodiments, the control and processing circuit can control the working light sources in the light source array to emit spot light beams according to the adjusted light intensity; synchronously control the working pixels corresponding to the working light sources in the pixel array to turn on and receive at least part of the spot light beams reflected by the target object to output photon detection signals.

[0040] The control and processing circuit 13 synchronizes the trigger signals of the emitter 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 activated (i.e., actuated) and / or deactivated (i.e., turned off). Various detection information generated by the readout circuit can be fed back to the control and processing circuit 13 for subsequent use. In one embodiment, the working pixel responds to a single incident photon and outputs a photon detection signal, that is, a photon detection event occurs. The readout circuit receives multiple photon detection signals from the working pixels and processes them to generate a histogram; alternatively, the readout circuit receives multiple photon detection signals from the working pixels and counts their number. The control and processing circuit 13 receives the histogram and adjusts the luminous intensity of the light source according to the maximum value or average value of the corresponding values of each time bin in the histogram; alternatively, the control and processing circuit 13 receives the number of photon detection events and adjusts the luminous intensity of the light source according to the number.

[0041] It is understandable that the control and processing circuit 13 can be an independent dedicated circuit, such as a dedicated system on chip (SOC), an off-the-shelf field-programmable gate array (FPGA) chip, an application-specific integrated circuit (ASIC) chip, etc., and can also include a general-purpose processing circuit.

[0042] In some embodiments, the dToF-based detection system 10 further includes a memory. The memory can be used to store a pulse encoding program, which is used to control the excitation timing, emission frequency, light intensity, and driving circuit of the light beam emitted by the light source 111. The memory can be used to store time difference values, time bins, time codes, histograms, time-of-flight values, the number of photon detection signals, and distance information.

[0043] In some embodiments, the dToF-based detection system 10 may also include devices such as color cameras, infrared cameras, IMUs, etc. The combination of these devices can achieve richer functions, such as 3D texture modeling, infrared face recognition, SLAM and other functions.

[0044] The embodiment of the present application also provides a light source adjustment method for a dToF-based detection system. The light source adjustment method for a dToF-based detection system can be applied to the dToF-based detection system of the aforementioned embodiment. In some embodiments, the light source adjustment method for a dToF-based detection system can be executed by a control and processing circuit for a dToF-based detection system. In some embodiments, the light source adjustment method for a dToF-based detection system can be executed by an electronic device. It should be noted that the light source adjustment method for a dToF-based detection system in the embodiment of the light source adjustment method for a dToF-based detection system that is not described in detail can be found in the foregoing, and will not be repeated here.

[0045] like Figure 3 As shown, an embodiment of the present application provides a light source adjustment method for a dToF-based detection system, which may include the following steps S31 to S33.

[0046] S31 , controlling a working light source in a transmitter to emit a spot light beam toward a target object according to a first light intensity.

[0047] In one embodiment, the emitter includes a light source array composed of a plurality of light sources. The working light sources emit a spot light beam of a first light intensity toward the target object under the control of the control and processing circuit and driven by the driver.

[0048] S32, synchronously activating working pixels in a collector to receive at least a portion of the spot light beam reflected back by the target object and generating detection parameters of a photon detection event.

[0049] The detection parameters are information related to the photon detection event, and are used to characterize the received light intensity. The detection parameters include: the grayscale value of the working pixel, and the maximum value or average value of the corresponding values of each time interval in the histogram.

[0050] The collector includes a pixel array composed of multiple pixels and a readout circuit array composed of multiple readout circuits. The working pixels output photon detection signals in response to the incidence of photons in the spot light beam reflected by the target object. The readout circuit is used to count the number of photon detection signals output by the working pixels. The readout circuit can also be used to generate a histogram based on the photon detection signals.

[0051] In some embodiments, the readout circuit includes a counting circuit, each pixel is connected to a counting circuit, and the counting circuit is used to count the number of photon detection signals output by the corresponding pixel. The control and processing circuit receives the number of photon detection signals.

[0052] In some embodiments, the readout circuit further includes a TDC circuit and a histogram circuit, wherein the TDC circuit is configured to generate a time signal according to the photon detection signal, and the histogram circuit is configured to generate a histogram according to the time signal. The control and processing circuit receives the histogram.

[0053] Specifically, a single photon incident on a pixel will cause an avalanche (or exposure), and the pixel will output an avalanche signal to the TDC circuit. The TDC circuit then detects the time signal from the photon being emitted from the emitter to the time the avalanche is caused. This time signal is used to find the corresponding time bin in the histogram circuit, so that the corresponding value of the time bin is increased by 1, that is, the photon count value within the time bin is increased by 1. After multiple detections, the time bins are statistically analyzed by histogram to restore the waveform of the entire pulse signal, thereby achieving accurate time-of-flight detection. Finally, the distance information of the target object can be calculated based on the time-of-flight. For example, assuming that the pulse period of the pulse signal emitted by the light source is T, the histogram circuit is configured to include multiple time bins, and the sum of the multiple time bins (recorded as the measurement time range of the histogram circuit) is equal to the pulse period T. Then the number of time bins m = T / Δt, where Δt is the size of the time bin. Figure 4 An example of a histogram is given schematically.

[0054] S33: Adjust the first light intensity of the working light source according to the detection parameter.

[0055] The first light intensity of the working light source is adjusted according to the detection parameters to reach the target intensity, so that the working pixels in the collector receive the target number of photons C. tgIt should be noted that the target photon number C tg You can use an empirical value, and this application does not limit this.

[0056] In some embodiments, step S33 specifically includes: determining a driving current change value of the working light source based on the detection parameter, determining a current driving current based on the initial driving current value and the driving current change value, and controlling the working light source to turn on according to the current driving current. The initial driving current value is the driving current corresponding to the first light intensity.

[0057] In one embodiment, the detection parameter is a statistical number of photon detection events. That is, the detection parameter C n =Total number of photon detection events, ie, the cumulative sum of all photon exposure times. In this embodiment, the first light intensity of the working light source is adjusted according to the statistical number of photon detection events.

[0058] As an implementation method, according to the formula ΔI1=a1(C tg -C n1 )+b1 calculates the driving current change value ΔI1, where a1 and b1 are coefficients, C tg is the target photon number, C n1 is the statistical number of photon detection events. According to formula I n1 =I base +ΔI1 calculates the current driving current I n1 , where I base is the initial value of the driving current.

[0059] In one embodiment, the detection parameter is the maximum value of the values corresponding to each time bin in the histogram. In this embodiment, the control and processing circuit receives the histogram from the readout circuit, determines the maximum value of the values corresponding to each time bin in the histogram, and adjusts the first light intensity of the working light source based on the maximum value.

[0060] As an implementation method, according to the formula ΔI2=a2(C tg -C n2 )+b2 calculates the driving current change value ΔI2, where a2 and b2 are coefficients, C tg is the target photon number, C n2 is the maximum value of each time bin in the histogram. Then according to formula I n2 =I base +ΔI2 calculates the current driving current I n2 , where I base is the initial value of the driving current.

[0061] In one embodiment, the detection parameter is an average value of the values corresponding to each time bin in the histogram. In this embodiment, the control and processing circuit receives the histogram from the readout circuit, calculates the average value of the values corresponding to each time bin in the histogram, and adjusts the first light intensity of the working light source based on the average value.

[0062] As an implementation method, according to the formula ΔI3=a3(C tg -C n3 )+b3 calculates the driving current change value ΔI3, where a3 and b3 are coefficients, C tg is the target photon number, C n3 is the average value of the corresponding value of each time bin in the histogram. Then according to formula I n3 =I base +ΔI3 calculates the current driving current I n3 , where I base is the initial value of the driving current.

[0063] It should be noted that, in the three different implementations, a1, a2, and a3 may take different values, and b1, b2, and b3 may take different values.

[0064] In the embodiment of the present application, the luminous intensity of the light source can be adjusted according to the detection parameters of the photon detection event during the detection process of the target object, thereby realizing dynamic adjustment of the light source. During detection, the optimal luminous intensity at the emission end of the detection system can be determined, and the optimal number of photons can be received at the collection end, thereby completing accurate detection. It can match different detection environments, avoid the loss of accuracy caused by changes in the detection environment, and avoid the waste of histogram storage resources caused by consuming more histogram storage resources to match different detection environments, thereby saving histogram storage resources.

[0065] Optionally, in some embodiments, based on step S33, the process further includes: controlling the working light sources in the light source array to emit a detection beam toward the target at an adjusted light intensity; synchronously controlling the working pixels in the pixel array to turn on and receive at least a portion of the detection beam reflected by the target to generate a photon detection signal; obtaining a histogram generated by the readout circuit array based on the photon detection signals output by the working pixels, calculating the flight time from the emission to the reception of the detection beam based on the histogram, and calculating the distance information of the target based on the flight time. This process is performed after the detection system adjusts the light intensity of the light source and then uses the adjusted detection system to perform target detection.

[0066] Specifically, in these embodiments, the readout circuit is further configured to generate a histogram based on the photon detection signals output by the working pixels.

[0067] An embodiment of the present application also provides an electronic device. Figure 5As shown, the electronic device includes: a processor 1000, a memory 1001, and a computer program 1002 stored in the memory 1001 and executable on the processor 1000, such as a light source adjustment program for a dToF-based detection system. When the processor 1000 executes the computer program 1002, the steps of the light source adjustment method for a dToF-based detection system in any of the above embodiments are implemented, such as Figure 3 Steps S31 to S33 are shown.

[0068] Exemplarily, the computer program 1002 may be divided into one or more modules / units, which are stored in the memory 1001 and executed by the processor 1000 to complete the present application. The one or more modules / units may be a series of computer program instruction segments capable of performing specific functions, and the instruction segments are used to describe the execution process of the computer program 1002 in the electronic device.

[0069] Those skilled in the art will understand that Figure 5 These are merely examples of electronic devices and do not constitute limitations on the electronic device. The electronic device may include more or fewer components than shown in the figure, or a combination of certain components, or different components. For example, the electronic device may also include input and output devices, network access devices, buses, etc.

[0070] The processor 1000 may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), ASICs, FPGAs, or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. A general-purpose processor may be a microprocessor or any conventional processor.

[0071] The memory 1001 may be an internal storage unit of an electronic device, such as a hard disk or memory of the electronic device. The memory 1001 may also be an external storage device of the electronic device, such as a plug-in hard disk, a smart memory card (Smart Media Card, SMC), a secure digital (Secure Digital, SD) card, a flash card (FlashCard), etc. equipped on the electronic device. Furthermore, the memory 1001 may also include both an internal storage unit of the electronic device and an external storage device. The memory 1001 is used to store the computer program and other programs and data required by the electronic device. The memory 1001 may also be used to temporarily store data that has been output or is to be output.

[0072] An embodiment of the present application further provides an electronic device, which includes the dToF-based detection system of any of the aforementioned embodiments, wherein the transmitter and collector of the detection system are disposed on the same side of the electronic device body.

[0073] As a non-limiting example, the electronic device may be a lidar or the like.

[0074] An embodiment of the present application provides a computer-readable storage medium storing a computer program. When the computer program is executed by a processor, the steps in each of the above-mentioned light source adjustment method embodiments of the dToF-based detection system can be implemented.

[0075] An embodiment of the present application provides a computer program product. When the computer program product is run on an electronic device, the electronic device can implement the steps in the above-mentioned embodiments of the light source adjustment method for the dToF-based detection system.

[0076] In the above embodiments, the description of each embodiment has its own focus. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant description of other embodiments.

[0077] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0078] In the embodiments provided in this application, it should be understood that the disclosed devices / electronic devices and methods can be implemented in other ways. For example, the device / electronic device embodiments described above are merely schematic. For example, the division of modules or units is merely a logical function division. In actual implementation, there may be other division methods, such as 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 mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0079] Units described as separate components may or may not be physically separate, and components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0080] In addition, the functional units in the various embodiments of the present application may be integrated into a single processing unit, or each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0081] If 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, the present application implements all or part of the processes in the above-mentioned embodiment method, and can also be completed by a computer program to instruct the relevant hardware. The computer program can be stored in a computer-readable storage medium. When the computer program is executed by the processor, it can implement the steps of each of the above-mentioned method embodiments. Among them, the computer program includes computer program code, which can be in source code form, object code form, executable file or some intermediate form. Computer-readable media 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, electric carrier signal, telecommunication signal and software distribution medium. It should be noted that the content contained in the computer-readable medium can be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, computer-readable media do not include electric carrier signals and telecommunication signals.

[0082] The above are only preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A light source adjustment method for a dToF-based detection system, characterized in that: include: Controlling a working light source in the transmitter to emit a spot light beam toward the target object at a first light intensity; Synchronously activating working pixels in a collector to receive at least a portion of the spot light beam reflected by the target object and generate detection parameters of a photon detection event, wherein the photon detection event is an event in which the working pixel outputs a photon detection signal in response to incident photons; Adaptively adjusting the first light intensity of the working light source according to the detection parameter so that the first light intensity reaches a target intensity, thereby causing the working pixel in the collector to receive a target number of photons; comprising: determining a driving current change value of the working light source according to the detection parameter, determining a current driving current according to an initial driving current value and the driving current change value, and controlling the working light source to turn on according to the current driving current, wherein the initial driving current value is the driving current corresponding to the first light intensity; Wherein, determining the driving current change value of the working light source according to the detection parameter includes: According to the formula Calculate the driving current change value , where a and b are coefficients, is the target photon number, The detection parameter is used to characterize the received light intensity, including: the grayscale value of the working pixel, and the maximum value or average value of the corresponding values of each time interval in the histogram.

2. The light source adjustment method according to claim 1, wherein: The grayscale value of the working pixel is the statistical number of the photon detection event.

3. The light source adjustment method according to claim 1, wherein: Determining the current driving current according to the initial driving current value and the driving current change value includes: According to the formula Calculate the current driving current ,in, is the initial value of the driving current, is the driving current change value.

4. A dToF-based detection system, characterized in that: include: Transmitter, collector, and control and processing circuits, The emitter is configured to turn on the working light source and emit a spot light beam toward the target object at a first light intensity; The collector is configured to activate working pixels to receive at least a portion of the spot light beam reflected by the target object and generate detection parameters of a photon detection event, wherein the photon detection event is an event in which the working pixel outputs a photon detection signal in response to the incidence of a photon; The control and processing circuit is configured to adjust the first light intensity of the working light source according to the detection parameter so that the first light intensity reaches a target intensity, thereby causing the working pixel in the collector to receive a target number of photons; including: determining a driving current change value of the working light source according to the detection parameter, determining a current driving current according to an initial driving current value and the driving current change value, and controlling the working light source to turn on according to the current driving current, wherein the initial driving current value is the driving current corresponding to the first light intensity; Wherein, determining the driving current change value of the working light source according to the detection parameter includes: According to the formula Calculate the driving current change value , where a and b are coefficients, is the target photon number, The detection parameter is used to characterize the received light intensity, including: the grayscale value of the working pixel, and the maximum value or average value of the corresponding values of each time interval in the histogram.

5. The dToF-based detection system according to claim 4, wherein: The collector includes a pixel array composed of multiple pixels and a readout circuit array composed of multiple readout circuits. The pixels are connected to the readout circuits in a one-to-one correspondence. The event in which the working pixels output a photon detection signal in response to the incidence of photons is a photon detection event. The readout circuit is used to generate detection parameters for the photon detection event.

6. The dToF-based detection system according to claim 5, wherein: The readout circuit includes a counting circuit, which is used to count the statistical number of the photon detection events of the working pixel; the control and processing circuit is configured to use the statistical number as a detection parameter.

7. The dToF-based detection system according to claim 5, wherein: The readout circuit includes a TDC circuit and a histogram circuit, wherein the TDC circuit is used to generate a time signal based on the photon detection signal output by the working pixel, and the histogram circuit is used to generate a histogram based on the time signal; the control and processing circuit is configured to use the maximum value of the values corresponding to each time interval in the histogram as the detection parameter, or to calculate the average value of the values corresponding to each time interval in the histogram as the detection parameter.

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