CN111812661A - Distance measuring method and system - Google Patents
Distance measuring method and system Download PDFInfo
- Publication number
- CN111812661A CN111812661A CN202010577154.2A CN202010577154A CN111812661A CN 111812661 A CN111812661 A CN 111812661A CN 202010577154 A CN202010577154 A CN 202010577154A CN 111812661 A CN111812661 A CN 111812661A
- Authority
- CN
- China
- Prior art keywords
- pixel
- dynamic
- pixels
- photons
- light beam
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000000034 method Methods 0.000 title claims abstract description 40
- 230000003213 activating effect Effects 0.000 claims abstract description 18
- 230000007613 environmental effect Effects 0.000 claims abstract description 10
- 238000012545 processing Methods 0.000 claims description 23
- 230000001276 controlling effect Effects 0.000 claims description 20
- 230000001105 regulatory effect Effects 0.000 claims description 16
- 238000005259 measurement Methods 0.000 claims description 15
- 238000000691 measurement method Methods 0.000 claims description 9
- 230000002123 temporal effect Effects 0.000 claims description 6
- 230000004913 activation Effects 0.000 claims description 5
- 238000010008 shearing Methods 0.000 claims description 3
- 230000000875 corresponding effect Effects 0.000 description 20
- 230000003287 optical effect Effects 0.000 description 15
- 238000010586 diagram Methods 0.000 description 13
- 238000003384 imaging method Methods 0.000 description 10
- 230000001360 synchronised effect Effects 0.000 description 10
- 238000004590 computer program Methods 0.000 description 4
- 230000006870 function Effects 0.000 description 4
- 230000008569 process Effects 0.000 description 4
- 230000008878 coupling Effects 0.000 description 3
- 238000010168 coupling process Methods 0.000 description 3
- 238000005859 coupling reaction Methods 0.000 description 3
- 238000004891 communication Methods 0.000 description 2
- 239000002131 composite material Substances 0.000 description 2
- 230000009849 deactivation Effects 0.000 description 2
- 238000006073 displacement reaction Methods 0.000 description 2
- 230000003068 static effect Effects 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 238000001161 time-correlated single photon counting Methods 0.000 description 2
- 101000822633 Pseudomonas sp 3-succinoylsemialdehyde-pyridine dehydrogenase Proteins 0.000 description 1
- 238000003491 array Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 230000002596 correlated effect Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000005284 excitation Effects 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 239000004973 liquid crystal related substance Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000004044 response Effects 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 238000007493 shaping process Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S17/00—Systems using the reflection or reradiation of electromagnetic waves other than radio waves, e.g. lidar systems
- G01S17/02—Systems using the reflection of electromagnetic waves other than radio waves
- G01S17/06—Systems determining position data of a target
- G01S17/08—Systems determining position data of a target for measuring distance only
- G01S17/10—Systems determining position data of a target for measuring distance only using transmission of interrupted, pulse-modulated waves
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/48—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S17/00
- G01S7/483—Details of pulse systems
- G01S7/484—Transmitters
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/48—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S17/00
- G01S7/483—Details of pulse systems
- G01S7/486—Receivers
- G01S7/4865—Time delay measurement, e.g. time-of-flight measurement, time of arrival measurement or determining the exact position of a peak
Abstract
The invention provides a distance measuring method and a system, wherein the method comprises the following steps: controlling the transmitter to transmit a pulse beam to the target space; controlling a plurality of dynamic pixels in a pixel unit of a collector to collect photons in a pulse light beam reflected by a measured object and form a first photon signal; the dynamic pixels comprise a first pixel and a second pixel, each pixel is controlled independently, the first pixel is used for collecting photons of the pulse light beam reflected by the measured object, and the second pixel is used for collecting environmental photons; determining a position of a first pixel within the dynamic pixel from the first photon signal; activating the first pixel according to the position of the first pixel, and closing the second pixel; controlling the first pixel to collect the photons reflected by the measured object again and forming a second photon signal; the time of flight and/or distance of the pulsed light beam is calculated from the second photon signal. The signal quality of the pixel output is improved.
Description
Technical Field
The invention relates to the technical field of distance measurement, in particular to a distance measurement method and system.
Background
A distance measurement may be performed on a target using a Time of Flight (TOF) principle to obtain a depth image including a depth value of the target, and a distance measurement system based on the Time of Flight principle has been widely used in the fields of consumer electronics, unmanned driving, AR/VR, and the like. A distance measuring system based on the time-of-flight principle generally comprises an emitter and a collector, the field of view of a target is illuminated by a pulsed light beam emitted by the emitter and a reflected light beam is collected by the collector, and the distance to the object is calculated by calculating the time required for the light beam to be received from emission to reflection.
The current distance measuring system based on the time-of-flight principle comprises a pixel array, in particular a pixel array based on a single photon avalanche photodiode (SPAD). As described in chinese patent CN201910888927.6, in order to receive as many light signals as possible from the reflected light beam, a plurality of pixels are generally used in combination, and the corresponding pixel region is called "combined pixel". When the emitter and the collector are configured as an off-axis measurement system, under the influence of parallax, an imaging light spot formed by a reflected light beam incident on a pixel array is displaced, so that the position of a combined pixel is uncertain, and therefore, a 'super-pixel technology' is provided to solve the problem. It is therefore a problem to be solved how to avoid interference of pixels receiving ambient photons.
The above background disclosure is only for the purpose of assisting understanding of the concept and technical solution of the present invention and does not necessarily belong to the prior art of the present patent application, and should not be used for evaluating the novelty and inventive step of the present application in the case that there is no clear evidence that the above content is disclosed at the filing date of the present patent application.
Disclosure of Invention
The invention provides a distance measuring method and system for solving the existing problems.
In order to solve the above problems, the technical solution adopted by the present invention is as follows:
a distance measurement method comprising: s1: controlling the transmitter to transmit a pulse beam to the target space; s2: controlling a plurality of dynamic pixels in a pixel unit of a collector to collect photons in the pulse light beam reflected by the object to be measured and form a first photon signal; the dynamic pixels comprise a first pixel and a second pixel, and each pixel is controlled individually, the first pixel is used for collecting photons in the pulse light beam reflected by the object to be measured, and the second pixel is used for collecting environmental photons; s3: determining a location of the first pixel within the dynamic pixel from the first photon signal; s4: activating the first pixel and closing the second pixel according to the position of the first pixel; s5: controlling the first pixel to collect photons in the pulsed light beam reflected by the measured object again and form a second photon signal; s6: calculating a time of flight and/or distance of the pulsed light beam from the second photon signal.
In one embodiment of the present invention, the pixels are activated or deactivated by regulating a bias voltage applied to each of the pixels within the dynamic pixel. Activating the first pixel according to the position of the first pixel, and turning off the second pixel comprises: determining a type of each pixel in the dynamic pixels according to the position of the first pixel, wherein the type is the first pixel or the second pixel; acquiring the state stored by a storage unit connected with each pixel, wherein the state comprises activation or closing; and regulating bias voltage applied to the pixels according to the type and the state of each pixel to activate the first pixel and deactivate the second pixel. Activating the first pixel according to the position of the first pixel, and turning off the second pixel comprises: determining a type of each pixel of the dynamic pixels according to the position of the first pixel, wherein the type is the first pixel or the second pixel; the width or the height of the dynamic pixel is consistent with the diameter of a light spot formed by the pulse light beam reflected by the measured object; and controlling a column selection circuit or a row selection circuit arranged outside the dynamic pixel to activate the column or the row of the first pixel, and close the column or the row of the second pixel. And the column selection circuit or the row selection circuit regulates and controls the bias voltage applied to the dynamic pixel through a logic switch. Activating the first pixel according to the position of the first pixel, and turning off the second pixel comprises: determining a type of each pixel in the dynamic pixels according to the position of the first pixel, wherein the type is the first pixel or the second pixel; sending control signals to digital to analog converters connected to each of said dynamic pixels; and regulating the bias voltage applied to the pixel to be a voltage value corresponding to the control signal so as to activate the first pixel and close the second pixel.
In another embodiment of the present invention, determining the location of the first pixel within the dynamic pixel from the first photon signal comprises: controlling each pixel in the dynamic pixels to be in an activated state so as to collect photons in the pulsed light beam reflected back by the object to be measured and output the first photon signal; counting at a first time resolution to calculate a first flight time, and calculating the position of the first pixel by combining parallax; wherein the first temporal resolution is a low temporal resolution. Determining a location of the first pixel within the dynamic pixel from the first photon signal comprises: controlling each pixel in the dynamic pixels to be in an activated state so as to collect photons in the pulsed light beam reflected back by the object to be measured and output the first photon signal; and acquiring a corresponding gray value according to the number of photons collected by each pixel in the dynamic pixel, and setting a gray value threshold value for determining the position of the first pixel in the dynamic pixel. Determining a location of the first pixel within the dynamic pixel from the first photon signal comprises: activating each pixel in the dynamic pixels one by one to collect photons and then outputting photon signals and drawing a first histogram; after all pixels in the dynamic pixels are activated, shearing the first histogram to only reserve signal peaks in the first histogram, and calculating first flight time according to the positions of the signal peaks or calculating a gray value according to the number of photons at the signal peaks; and determining the position of the first pixel according to the first flight time or the gray value.
The invention also provides a distance measuring system based on dynamic pixels, comprising: a transmitter for transmitting a pulsed light beam to a target space; the collector is used for collecting photons in the pulsed light beam reflected by the measured object and forming photon signals; the collector comprises a plurality of dynamic pixels; the dynamic pixel collects photons in the pulse light beam reflected by the measured object and forms a first photon signal; the dynamic pixels comprise a first pixel and a second pixel, and each pixel is controlled independently, the first pixel is used for collecting photons of the pulse light beam reflected by the measured object, and the second pixel is used for collecting environmental photons; control and processing circuitry, coupled to the transmitter and the collector, for performing the method of any of the above.
The invention has the beneficial effects that: the distance measuring method and system are characterized in that each pixel state in the dynamic pixels is independently controlled by setting the dynamic pixels, photons in pulse light beams reflected by different measured objects are collected as much as possible by activating the first pixels and closing the second pixels, and interference of environmental noise on output signals is reduced, so that the signal quality output by the pixels is improved, and the distance measuring precision is improved.
Further, the present invention provides a method of turning on or off a pixel by modulating a bias voltage applied across the pixel.
Drawings
Fig. 1 is a schematic diagram of a distance measuring system according to an embodiment of the present invention.
Fig. 2 is a schematic diagram of a pixel unit according to an embodiment of the invention.
Fig. 3 is a schematic diagram of a distance measuring method according to an embodiment of the present invention.
Fig. 4 is a schematic diagram of a first method for determining a position of a first pixel within a dynamic pixel according to a first photon signal in an embodiment of the present invention.
FIG. 5 is a diagram of another pixel unit according to an embodiment of the present invention.
FIG. 6 is a diagram illustrating a second method for determining a position of a first pixel within a dynamic pixel based on a first photon signal according to an embodiment of the present invention.
FIG. 7 is a diagram illustrating a third method for determining a position of a first pixel within a dynamic pixel according to a first photon signal according to an embodiment of the present invention.
Fig. 8(a) -8 (e) are schematic structural diagrams of a pixel in an embodiment of the invention.
Fig. 9 is a schematic diagram of a first method for activating a first pixel and deactivating a second pixel according to the position of the first pixel according to the embodiment of the present invention.
Fig. 10 is a schematic diagram illustrating a second method for turning on a first pixel and turning off a second pixel according to the position of the first pixel according to the embodiment of the present invention.
Fig. 11 is a schematic diagram illustrating a third method for turning on the first pixel and turning off the second pixel according to the position of the first pixel according to the embodiment of the present invention.
Detailed Description
In order to make the technical problems, technical solutions and advantageous effects to be solved by the embodiments of the present invention more clearly apparent, the present invention is further described in detail below with reference to the accompanying drawings and the embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or be indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or be indirectly connected to the other element. In addition, the connection may be for either a fixing function or a circuit connection function.
It is to be understood that the terms "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are used in an orientation or positional relationship indicated in the drawings for convenience in describing the embodiments of the present invention and to simplify the description, and are not intended to indicate or imply that the referenced device or element must have a particular orientation, be constructed in a particular orientation, and be in any way limiting of the present invention.
Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed 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 that feature. In the description of the embodiments of the present invention, "a plurality" means two or more unless specifically limited otherwise.
Fig. 1 is a schematic diagram of a distance measuring system 10 according to an embodiment of the present invention, which includes a transmitter 11, a collector 12, and a control and processing circuit 13. Wherein, the emitter 11 is used to emit a light beam 30 to the target area 20, the light beam 30 is emitted to the target area space to illuminate the target object in the space, at least a part of the emitted light beam 30 is reflected by the target area 20 to form a reflected light beam 40, at least a part of the reflected light beam 40 is received by the collector 12, the control and processing circuit 13 is respectively connected with the emitter 11 and the collector 12, the trigger signals of the emitter 11 and the collector 12 are synchronized to calculate the time required by the light beam from emission to reception, i.e. the flight time t between the emitted light beam 30 and the reflected light beam 40, further, the distance D of the corresponding point on the target object can be calculated by the following formula:
D＝c·t/2(1)
where c is the speed of light.
The transmitter 11 includes a light source 111, a transmitting optical element 112, a driver 113, and the like. The light source 111 may be a Light Emitting Diode (LED), a Laser Diode (LD), an Edge Emitting Laser (EEL), a Vertical Cavity Surface Emitting Laser (VCSEL), or the like, or may be a one-dimensional or two-dimensional light source array composed of a plurality of light sources, preferably, the light source array is a VCSEL array light source chip formed by generating a plurality of VCSEL light sources on a single semiconductor substrate, and the arrangement of the light sources in the light source array may be regular or irregular. The light beam emitted by the light source 111 may be visible light, infrared light, ultraviolet light, or the like. The light source 111 emits a light beam outward under the control of the driver 113. In one embodiment, the light source 111 emits a pulsed light beam outward under the control of the driver 113 at a frequency (pulse period) that can be used in Direct time of flight (Direct TOF) measurements, the frequency being set according to the measurement distance. It will be appreciated that the light beam emitted by the light source 111 may also be controlled by means of a part of the control and processing circuit 13 or a sub-circuit present independently of the control and processing circuit 13.
The emission optical element 112 receives the light beam emitted from the light source 111 and projects the light beam to a target region after shaping. In one embodiment, the transmitting optical element 112 receives the pulsed light beam from the light source 111 and optically modulates, such as diffracting, refracting, reflecting, etc., the pulsed light beam, and then transmits the modulated light beam, such as a focused light beam, a flood light beam, a structured light beam, etc., into space. The emitting optical elements 112 may be in the form of one or more combinations of lenses, liquid crystal elements, diffractive optical elements, microlens arrays, Metasurface (Metasurface) optical elements, masks, mirrors, MEMS mirrors, and the like.
And the control and processing circuit 13 synchronizes the trigger signals of the emitter 11 and the collector 12, processes the photon signals of the pixel collected light beams, and calculates the distance information of the target to be measured based on the flight time of the reflected light beams. In one embodiment, the SPAD outputs a photon signal in response to an incident single photon, and the control and processing circuitry 13 receives the photon signal and performs signal processing to obtain the time of flight of the beam. In particular, the control and processing circuit 13 calculates the number of photons collected to form successive time bins, which are joined together to form a statistical histogram for reconstructing the time series of the reflected beam, and identifies the time of flight of the reflected beam from emission to reception using peak matching and filtering detection. It will be appreciated that the control and processing circuitry 13 may be separate dedicated circuitry, such as a dedicated SOC chip, FPGA chip, ASIC chip, etc., or may comprise general purpose processing circuitry.
In some embodiments, the distance measurement system 10 further includes a memory for storing a pulse code program with which to control the excitation time, emission frequency, etc. of the light beam emitted by the light source 111.
In some embodiments, the distance measurement system 10 may further include a color camera, an infrared camera, an IMU, etc., and a combination thereof may implement more rich functions, such as 3D texture modeling, infrared face recognition, SLAM, etc.
In some embodiments, emitter 11 and collector 12 may be arranged coaxially, i.e. they are implemented by an optical device with reflection and transmission functions, such as a half-mirror.
Fig. 2 is a schematic diagram of a pixel cell according to an embodiment of the invention. The pixel unit includes a pixel array 22 and a readout circuit 23, wherein the pixel array 22 includes a two-dimensional array composed of a plurality of pixels, and the readout circuit 23 includes a TDC circuit 231 and a histogram circuit 232. The pixel array 22 is configured to collect at least a part of the light beams reflected by the object and generate corresponding photon signals, and the readout circuit 23 is configured to process the photon signals to draw a histogram reflecting a pulse waveform emitted by a light source in the emitter, and further, calculate a flight time according to the histogram, and finally output the result. The readout circuit 23 may be a single TDC circuit and a histogram circuit, or may be an array readout circuit including a plurality of TDC circuits and histogram circuits.
In one embodiment, when emitter 11 emits a speckle beam to a measured object, pixel units in collector 12 direct the speckle beam to corresponding pixels, ideally, a spot of a reflected beam corresponds to a pixel, and actually, a plurality of pixels are arranged to correspond to a spot, wherein an imaging spot of a single speckle beam is configured to be incident on a "combined pixel" formed by a plurality of corresponding pixels. When the arrangement mode of emitter 11 and collector 12 is off-axis, due to the existence of parallax, it is necessary to consider that the light spot is subjected to displacement caused by different distances of the measured object, and therefore, a pixel region (super-pixel) composed of a plurality of pixels exceeding the number of combined pixels needs to be arranged for receiving the reflected spot light beam. Although the optical signals of the reflected light beam can be received as much as possible, some pixels are in an activated state and do not collect photons in the reflected light beam for receiving ambient photons, and the final output photon signals are interfered.
In the embodiment of the present invention, in order to solve the problem of interference of pixels which do not receive a light spot on an output photon signal, on and off states of each pixel need to be dynamically regulated, and these pixels are called "dynamic pixels", and each of the dynamic pixels can be independently controlled. Generally, the number of dynamic pixels is the same as the number of spot beams acquired by collector 12 in a single measurement. The on and off states of each pixel are dynamically regulated, so that the pixels for collecting photons in the reflected light beam are activated, and the pixels for collecting environmental photon signals are in the off states; the interference of environmental noise to the final output signal is reduced while receiving photons as much as possible, so that the signal quality of pixel output is improved, and the accuracy of distance measurement is improved.
In one embodiment, the pixel array includes a plurality of dynamic pixels, each dynamic pixel is used for collecting the light beam reflected back in the corresponding field of view, the dynamic pixels include pixels for collecting photons in the light beams reflected back by the object to be measured at different distances, and one dynamic pixel corresponds to one light beam. The reflected beam is imaged to one side of the dynamic pixel when the target is at minimum range (left or right depending on the relative positions of the emitter and collector) and the reflected beam is imaged to the other side of the dynamic pixel when the target is at maximum range. Dynamic pixels can be set according to the displacement condition of light spots imaged by the reflected light beams caused by different distances of the measured object. In one embodiment, the dynamic pixel may be configured to include a plurality of subpixels, and the imaging spot of the reflected beam corresponds to one subpixel.
In one embodiment, as shown in fig. 2, the pixel array 22 comprises a two-dimensional array of 12 × 12 pixels for collecting at least part of the light beams reflected back from the object under test and generating corresponding photon signals, and the dynamic pixel 221 comprises 6 × 2 pixels for receiving the spot beams reflected back from the object under test at different distances. The reflected light spot at the minimum range is imaged onto the resultant pixel 223; the reflected spot at the furthest range is imaged onto a composite pixel 222. Each pixel in the dynamic pixels shares one TDC circuit, namely the TDC circuit is connected with each pixel in the dynamic pixels, and when any one pixel in the dynamic pixels receives photons and generates a photon signal, the TDC circuit can calculate the flight time corresponding to the photon signal. In one embodiment, the dynamic pixels may also be connected to an array of TDC circuits, i.e. each pixel in the dynamic pixel is connected to one TDC circuit.
As shown in fig. 3, based on the above description, the present invention provides a distance measuring method, which includes the following steps:
s1: controlling the transmitter to transmit a pulse beam to the target space;
s2: controlling a plurality of dynamic pixels in a pixel unit of a collector to collect photons in the pulse light beam reflected by the object to be measured and form a first photon signal; the dynamic pixels comprise a first pixel and a second pixel, and each pixel is controlled individually, the first pixel is used for collecting photons in the pulse light beam reflected by the object to be measured, and the second pixel is used for collecting environmental photons;
s3: determining a location of the first pixel within the dynamic pixel from the first photon signal;
s4: activating the first pixel and closing the second pixel according to the position of the first pixel;
s5: controlling the first pixel to collect photons in the pulsed light beam reflected by the measured object again and form a second photon signal;
s6: calculating a time of flight and/or distance of the pulsed light beam from the second photon signal.
It is understood that the dynamic pixel described herein includes a plurality of pixels corresponding to the light spots of the reflected light beam, and collects as many photons in the light beam reflected by the object to be measured as far as possible by activating the first pixel while closing the second pixel, and simultaneously reduces the interference of the environmental noise on the output signal.
The first pixel and the second pixel are only used for distinguishing whether photons collected by the pixels in the dynamic pixels belong to photons in a pulse light beam reflected back by a measured object or ambient photons, and the first pixel and the second pixel cannot limit the types of the pixels.
The idea for solving the problems is as follows: firstly, the position of a first pixel in dynamic pixels of pixel units in collector 12 is determined; the bias voltage on the pixel is then controlled to activate the first pixel and deactivate the second pixel.
The invention provides three methods for determining the position of the first pixel in the dynamic pixel according to the first photon signal, thereby further determining which pixels in the dynamic pixel are the first pixel and which are the second pixel. In some embodiments, the pixel may be a composite pixel.
In a first embodiment, the TDC circuitry comprises clocking modes with different time resolutions, i.e. comprises a coarse TDC circuit and a fine TDC circuit; the histograms may be plotted based on different time accuracies in the corresponding histogram circuits. In a single frame measurement period, the TDC circuit receives photon signals from pixels in a super-pixel region connected with the TDC circuit, calculates a time interval (namely flight time) between the signals and an initial clock signal, converts the time interval into a temperature code or a binary code and stores the temperature code or the binary code in a histogram circuit, and after multiple measurements, the histogram circuit can draw a histogram reflecting a pulse waveform, and the flight time of the pulse can be accurately obtained based on the histogram. In essence, the process of coarse positioning within a large measurement range and then fine measurement based on the positioning result is performed. Specifically, all pixels in the dynamic pixels are controlled to be in an activated state to collect photons in a reflected light beam to output a first photon signal, counting is performed with a first time resolution (lower time resolution) to calculate a first flight time (rough flight time), and then the position of the first pixel is calculated by combining parallax, so that the first pixel in the dynamic pixels can be regulated and controlled to be activated according to the position of the first pixel to collect photons of a pulse light beam reflected by a measured object to form a second photon signal for calculating the flight time; while the second pixel is turned off.
As shown in fig. 4, determining the position of the first pixel within the dynamic pixel from the first photon signal comprises the steps of:
controlling each pixel in the dynamic pixels to be in an activated state so as to collect photons in the pulsed light beam reflected back by the object to be measured and output the first photon signal;
counting at a first time resolution to calculate a first flight time, and calculating the position of the first pixel by combining parallax;
wherein the first temporal resolution is a low temporal resolution.
In a second embodiment, a corresponding gray value is obtained according to the number of photons collected by each pixel in the dynamic pixel, and a gray value threshold is set for determining the position of the pixel in the dynamic pixel, where the photon of the pulse beam reflected back by the object to be measured is collected.
As shown in fig. 5, taking a dynamic pixel 321 as an example for explanation, the readout circuit is connected to the dynamic pixel 321 for processing the optical signal to determine the position of the pixel for collecting the photons of the pulse beam reflected back by the object to be measured, i.e. the position of the first pixel. The mode selection unit 322 is connected to the dynamic pixel 321, in the step of determining the pixel position, the dynamic pixel 321 outputs a first photon signal, and the mode selection unit 322 inputs the first photon signal into the counter 323 for recording the number of photons collected by each pixel in the dynamic pixel, and the photon-by-photon exposure is realized by controlling the pixels in the dynamic pixel one by one. Or in one embodiment, each of the dynamic pixels 321 is configured to be connected to a readout circuit, and the readout circuits each process the number of photons collected by each pixel, and control the globally synchronized exposure of the pixels in the dynamic pixels 321. The gray data processing unit 324 determines the gray value of each pixel according to the number of photons recorded by the counter 323, and determines the position of the first pixel as the position of the combined pixel 327 according to the gray value, wherein the number of photons is positively correlated with the light intensity. It is understood that the combined pixel 327 here is composed of a dynamic pixel that collects photons of the pulse beam reflected back from the object to be measured, and each of the pixels is controlled individually. For example, the threshold of the gray scale value is pre-stored in the gray scale data processing unit 324, and the area composed of all the pixels with the gray scale value larger than the threshold is determined as the suitable pixel 327. The control and processing circuit 13 activates all pixels at the pixel 327 and turns off other pixels according to a specific control logic, collects photons with the pixel 327 and outputs a second photon signal, at which time the mode selection unit 322 inputs the second photon signal to the TDC circuit 325 and the histogram circuit 326 for calculating the time of flight.
As shown in fig. 6, determining the location of the first pixel within the dynamic pixel from the first photon signal comprises:
controlling each pixel in the dynamic pixels to be in an activated state so as to collect photons in the pulsed light beam reflected back by the object to be measured and output the first photon signal;
and acquiring a corresponding gray value according to the number of photons collected by each pixel in the dynamic pixel, and setting a gray value threshold value for determining the position of the first pixel in the dynamic pixel.
In a third embodiment, a first histogram is plotted according to a first photon signal output by a dynamic pixel, and a signal peak in the histogram is not obvious enough due to the influence of ambient photons collected by a part of pixels in the dynamic pixel on signal photons (photons in a reflected pulse light beam) when the histogram is plotted. And activating each pixel one by one to collect photons and then outputting a photon signal and drawing a first histogram, wherein if the photons collected by the pixel are signal photons, an obvious signal peak appears in the first histogram. After all the pixels in the dynamic pixel are activated, the first histogram is clipped to only retain the signal peak in the first histogram, and a first TOF value (coarse TOF value), i.e. a first time of flight, can be calculated according to the position of the signal peak, or a gray value can be calculated according to the number of photons at the signal peak, and then the position of the first pixel can be determined according to the first TOF value or the gray value, as described in the foregoing embodiment. In one embodiment, if the readout circuit connected to the dynamic pixel includes an array of TDC circuits and an array of histogram circuits, i.e., each pixel is connected to one of the TDC circuits and the histogram circuits, the global exposure of the dynamic pixel can be performed to determine the position of the first pixel according to the first histogram corresponding to each pixel.
As shown in fig. 7, determining the location of the first pixel within the dynamic pixel from the first photon signal comprises:
activating each pixel in the dynamic pixels one by one to collect photons and then outputting photon signals and drawing a first histogram;
after all pixels in the dynamic pixels are activated, shearing the first histogram to only reserve a signal peak in the first histogram, and calculating first flight time according to the position of the signal peak or calculating a gray value according to the number of photons at the signal peak;
and determining the position of the first pixel according to the first flight time or the gray value.
Specific control logic is executed to activate a first pixel of the dynamic pixels for collecting photons in the reflected pulsed light beam, while a second pixel is turned off, depending on the position of the first pixel.
The position of the first pixel in the dynamic pixel is determined by any of the methods described above, the type of the pixel in the dynamic pixel is determined, and then the first pixel is activated and the second pixel is deactivated by adjusting the bias voltage applied to the pixel. The adjustment of each of the dynamic pixels may be specifically achieved by the following method.
In a first embodiment, the pixels in the pixel cells of collector 12 are SPADs (single photon avalanche photodiodes), as shown in fig. 8(a) and 8(b), a memory unit (memory) is provided in the pixel for storing a state for controlling activation or deactivation of each pixel, when the control and processing circuit 13 determines the position of the pixel based on the first photon signal, the imaging position of the light spot (represented by a shaded circle) incident on the dynamic pixel 41 as shown in fig. 8(a) is the resultant pixel 411, i.e., the pixel in the combined pixel 411 is the first pixel, the control and processing circuit 13 outputs a regulation logic signal for regulating the state of the memory in the memory cell according to the position of the combined pixel 411, the bias voltage applied to the pixel is regulated according to the stored state, the pixel in the combined pixel 411 is activated and the other pixel in the dynamic pixel, i.e. the second pixel, is deactivated. In one embodiment, the storage unit stores a state of "0" or "1" characterizing the pixel, and when the state is "1", V is connectedddThe switch at terminal is closed, and the bias voltage across SPAD412 is Vop-Vdd(ii) a When the state is "0", V is connectedddThe switch at terminal is off, and the bias voltage across SPAD412 is VopThe bias voltage across SPAD412 is greater than the avalanche voltage and reaches a certain value (e.g., 3.3V) which can be used to detect photons in the reflected pulsed beam.
As shown in fig. 9, activating the first pixel and deactivating the second pixel according to the position of the first pixel comprises:
determining a type of each pixel in the dynamic pixels according to the position of the first pixel, wherein the type is the first pixel or the second pixel;
acquiring the state stored by a storage unit connected with each pixel, wherein the state comprises activation or closing;
and regulating bias voltage applied to the pixels according to the type and the state of each pixel to activate the first pixel and deactivate the second pixel.
In a second embodiment, as shown in fig. 8(c) and 8(d), a memory cell is not included in a pixel, and control logic for activating or deactivating each pixel is implemented by providing a column selection circuit outside the pixel array. Continuing with the description of an example of a dynamic pixel 42, in this embodiment, it is necessary to set the diameter of the imaging spot of the spot beam to be the same as the width of the dynamic pixel 42, and specifically, the imaging spot of the near reflected beam and the imaging spot of the far reflected beam can be adjusted by the receiving optical element 123 to be the same in diameter (generally, the imaging spot of the near reflected beam is larger than the imaging spot of the far reflected beam), and the imaging spot is shifted in the horizontal direction due to the parallax. When the control and processing circuit 13 determines that the position of the first pixel is the position of the combined pixel 421 according to the first photon signal, the control signal is output to the column selection circuit 43, and the column selection circuit 43 can determine that the corresponding multiple columns of pixels are activated synchronously, for example, the corresponding second, third, and fourth columns of pixels need to be in an activated state as shown in fig. 8(c), the column selection circuit 43 executes control logic to activate the pixels in the corresponding columns, that is, the bias voltage applied to the SPAD412 is regulated and controlled by a logic switch, the bias regulation and control is similar to that shown in fig. 8(b), and details are not repeated here. It will be appreciated that in some embodiments, a row selection circuit may be further provided, where the offset of the light spot caused by the parallax is along the vertical direction, and the specific arrangement is determined according to the position relationship between the emitter and the collector.
As shown in fig. 10, activating the first pixel and deactivating the second pixel according to the position of the first pixel comprises:
determining a type of each pixel of the dynamic pixels according to the position of the first pixel, wherein the type is the first pixel or the second pixel; the width or the height of the dynamic pixel is consistent with the diameter of a light spot formed by the pulse light beam reflected by the measured object;
and controlling a column selection circuit or a row selection circuit arranged outside the dynamic pixel to activate the column or the row of the first pixel, and close the column or the row of the second pixel.
In a third embodiment, as shown in FIG. 8(e), in this embodiment, the voltage applied across the SPAD412 pixels is Vexand-VBDTwo parts, when the SPAD412 is in the active state, the bias voltage (V) on the SPAD is regulatedex+VBD) Greater than the avalanche voltage. Specifically, a digital-to-analog converter (DAC) is arranged to be connected with the SPAD, and the voltage V applied to the SPAD is regulated and controlled through the DAC44exTo regulate the activation and deactivation of SPAD pixels. When the control and processing circuit 13 determines that the position of the pixel needs to activate the corresponding pixel according to the first photon signal, a control signal is sent to the DAC44, the DAC44 converts the signal quantity into a voltage value and outputs the voltage value to the SPAD, so as to regulate the bias voltage on the SPAD to be Vex+VBDUsually set VexWhen the voltage is 3.3V, the SAPD pixel can be activated; when the pixel needs to be turned off, the DAC44 regulates and controls the output voltage value Vex0, when the voltage applied across the SPAD is VBDThe avalanche phenomenon cannot be caused. A power amplifier 45 may be further provided for amplifying and boosting the output voltage signal of the DAC 44.
As shown in fig. 11, activating the first pixel and deactivating the second pixel according to the position of the first pixel comprises:
determining a type of each pixel in the dynamic pixels according to the position of the first pixel, wherein the type is the first pixel or the second pixel;
sending control signals to digital-to-analog converters connected to each of said dynamic pixels; and regulating the bias voltage applied to the pixel to be a voltage value corresponding to the control signal so as to activate the first pixel and close the second pixel.
The above method is merely exemplary, and other methods of regulating the magnitude of the bias voltage applied to the pixel in the prior art may be applied to the present invention.
An embodiment of the present application further provides a control apparatus, including a processor and a storage medium for storing a computer program; wherein a processor is adapted to perform at least the method as described above when executing the computer program.
Embodiments of the present application also provide a storage medium for storing a computer program, which when executed performs at least the method described above.
Embodiments of the present application further provide a processor, where the processor executes a computer program to perform at least the method described above.
The storage medium may be implemented by any type of volatile or non-volatile storage device, or combination thereof. Among them, the nonvolatile Memory may be a Read Only Memory (ROM), a Programmable Read Only Memory (PROM), an erasable Programmable Read-Only Memory (EPROM), an electrically erasable Programmable Read-Only Memory (EEPROM), a magnetic random Access Memory (FRAM), a Flash Memory (Flash Memory), a magnetic surface Memory, an optical Disc, or a Compact Disc Read-Only Memory (CD-ROM); the magnetic surface storage may be disk storage or tape storage. Volatile Memory can be Random Access Memory (RAM), which acts as external cache Memory. By way of illustration and not limitation, many forms of RAM are available, such as Static Random Access Memory (SRAM), Synchronous Static Random Access Memory (SSRAM), Dynamic Random Access Memory (DRAM), Synchronous Dynamic Random Access Memory (SDRAM), Double data rate Synchronous Dynamic Random Access Memory (DDRSDRAM, Double DataRateSync Synchronous Random Access Memory), Enhanced Synchronous Dynamic Random Access Memory (ESDRAM, Enhanced Synchronous Dynamic Random Access Memory), Synchronous link Dynamic Random Access Memory (SLDRAM, Synchronous Dynamic Random Access Memory (SLDRAM), Direct Memory (DRMBER, Random Access Memory). The storage media described in connection with the embodiments of the invention are intended to comprise, without being limited to, these and any other suitable types of memory.
In the several embodiments provided in the present application, it should be understood that the disclosed system and method may be implemented in other ways. The above-described device embodiments are merely illustrative, for example, the division of the unit is only a logical functional division, and there may be other division ways in actual implementation, 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 addition, the coupling, direct coupling or communication connection between the components shown or discussed may be through some interfaces, and the indirect coupling or communication connection between the devices or units may be electrical, mechanical or other forms.
The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, that is, may be located in one place, or may be distributed on a plurality of network units; some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.
In addition, all the functional units in the embodiments of the present invention may be integrated into one processing unit, or each unit may be separately regarded as one unit, or two or more units may be integrated into one unit; the integrated unit can be realized in a form of hardware, or in a form of hardware plus a software functional unit.
Those of ordinary skill in the art will understand that: all or part of the steps for implementing the method embodiments may be implemented by hardware related to program instructions, and the program may be stored in a computer readable storage medium, and when executed, the program performs the steps including the method embodiments; and the aforementioned storage medium includes: a mobile storage device, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk, and other various media capable of storing program codes.
Alternatively, the integrated unit of the present invention may be stored in a computer-readable storage medium if it is implemented in the form of a software functional module and sold or used as a separate product. Based on such understanding, the technical solutions of the embodiments of the present invention may be essentially implemented or a part contributing to the prior art may be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the methods described in the embodiments of the present invention. And the aforementioned storage medium includes: a removable storage device, a ROM, a RAM, a magnetic or optical disk, or various other media that can store program code.
The methods disclosed in the several method embodiments provided in the present application may be combined arbitrarily without conflict to obtain new method embodiments.
Features disclosed in several of the product embodiments provided in the present application may be combined in any combination to yield new product embodiments without conflict.
The features disclosed in the several method or apparatus embodiments provided in the present application may be combined arbitrarily, without conflict, to arrive at new method embodiments or apparatus embodiments.
The foregoing is a more detailed description of the invention in connection with specific preferred embodiments and it is not intended that the invention be limited to these specific details. For those skilled in the art to which the invention pertains, several equivalent substitutions or obvious modifications can be made without departing from the spirit of the invention, and all the properties or uses are considered to be within the scope of the invention.
Claims (10)
1. A distance measuring method, characterized by comprising:
s1: controlling the transmitter to transmit a pulse beam to the target space;
s2: controlling a plurality of dynamic pixels in a pixel unit of a collector to collect photons in the pulse light beam reflected by the object to be measured and form a first photon signal; the dynamic pixels comprise a first pixel and a second pixel, and each pixel is controlled individually, the first pixel is used for collecting photons in the pulse light beam reflected by the object to be measured, and the second pixel is used for collecting environmental photons;
s3: determining a location of the first pixel within the dynamic pixel from the first photon signal;
s4: activating the first pixel and closing the second pixel according to the position of the first pixel;
s5: controlling the first pixel to collect photons in the pulsed light beam reflected by the measured object again and form a second photon signal;
s6: calculating a time of flight and/or distance of the pulsed light beam from the second photon signal.
2. The distance measuring method of claim 1 wherein said pixels are activated or deactivated by regulating a bias voltage applied across each of said pixels within said dynamic pixels.
3. The distance measurement method according to claim 2, wherein the first pixel is activated according to a position of the first pixel, and the turning off of the second pixel comprises:
determining a type of each pixel in the dynamic pixels according to the position of the first pixel, wherein the type is the first pixel or the second pixel;
acquiring the state stored by a storage unit connected with each pixel, wherein the state comprises activation or closing;
and regulating bias voltage applied to the pixels according to the type and the state of each pixel to activate the first pixel and deactivate the second pixel.
4. The distance measurement method according to claim 2, wherein the first pixel is activated according to a position of the first pixel, and the turning off of the second pixel comprises:
determining a type of each pixel of the dynamic pixels according to the position of the first pixel, wherein the type is the first pixel or the second pixel; the width or the height of the dynamic pixel is consistent with the diameter of a light spot formed by the pulse light beam reflected by the measured object;
and controlling a column selection circuit or a row selection circuit arranged outside the dynamic pixel to activate the column or the row of the first pixel, and close the column or the row of the second pixel.
5. The distance measurement method of claim 4 wherein said column select circuit or row select circuit regulates the bias voltage applied across said dynamic pixels through a logic switch.
6. The distance measurement method according to claim 2, wherein the first pixel is activated according to a position of the first pixel, and the turning off of the second pixel comprises:
determining a type of each pixel in the dynamic pixels according to the position of the first pixel, wherein the type is the first pixel or the second pixel;
sending control signals to digital to analog converters connected to each of said dynamic pixels; and regulating the bias voltage applied to the pixel to be a voltage value corresponding to the control signal so as to activate the first pixel and close the second pixel.
7. The distance measurement method of any of claims 1-6 wherein determining the location of the first pixel within the dynamic pixel from the first photon signal comprises:
controlling each pixel in the dynamic pixels to be in an activated state so as to collect photons in the pulsed light beam reflected back by the object to be measured and output the first photon signal;
counting at a first time resolution to calculate a first flight time, and calculating the position of the first pixel by combining parallax;
wherein the first temporal resolution is a low temporal resolution.
8. The distance measurement method of any of claims 1-6 wherein determining the location of the first pixel within the dynamic pixel from the first photon signal comprises:
controlling each pixel in the dynamic pixels to be in an activated state so as to collect photons in the pulsed light beam reflected back by the object to be measured and output the first photon signal;
and acquiring a corresponding gray value according to the number of photons collected by each pixel in the dynamic pixel, and setting a gray value threshold value for determining the position of the first pixel in the dynamic pixel.
9. The distance measurement method of any of claims 1-6 wherein determining the location of the first pixel within the dynamic pixel from the first photon signal comprises:
activating each pixel in the dynamic pixels one by one to collect photons and then outputting photon signals and drawing a first histogram;
after all pixels in the dynamic pixels are activated, shearing the first histogram to only reserve signal peaks in the first histogram, and calculating first flight time according to the positions of the signal peaks or calculating a gray value according to the number of photons at the signal peaks;
and determining the position of the first pixel according to the first flight time or the gray value.
10. A dynamic pixel based distance measurement system, comprising:
a transmitter for transmitting a pulsed light beam to a target space;
the collector is used for collecting photons in the pulsed light beam reflected by the measured object and forming photon signals; the collector comprises a plurality of dynamic pixels; the dynamic pixel collects photons in the pulse light beam reflected by the measured object and forms a first photon signal; the dynamic pixels comprise a first pixel and a second pixel, and each pixel is controlled independently, the first pixel is used for collecting photons of the pulse light beam reflected by the measured object, and the second pixel is used for collecting environmental photons;
control and processing circuitry, connected to the transmitter and the collector, for performing the method of any of claims 1-9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010577154.2A CN111812661A (en) | 2020-06-22 | 2020-06-22 | Distance measuring method and system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010577154.2A CN111812661A (en) | 2020-06-22 | 2020-06-22 | Distance measuring method and system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111812661A true CN111812661A (en) | 2020-10-23 |
Family
ID=72845482
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010577154.2A Pending CN111812661A (en) | 2020-06-22 | 2020-06-22 | Distance measuring method and system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111812661A (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112799097A (en) * | 2021-04-14 | 2021-05-14 | 深圳阜时科技有限公司 | Method for acquiring depth map and gray scale map, depth camera and electronic equipment |
| CN113075674A (en) * | 2021-03-23 | 2021-07-06 | 深圳市灵明光子科技有限公司 | Ranging method and ranging system based on flight time |
| CN113504542A (en) * | 2021-07-07 | 2021-10-15 | 奥比中光科技集团股份有限公司 | Distance measuring system and method, device and equipment for calculating reflectivity of measured object |
| CN114494407A (en) * | 2022-04-14 | 2022-05-13 | 宜科(天津)电子有限公司 | Image processing method for distance measurement |
| WO2022110947A1 (en) * | 2020-11-25 | 2022-06-02 | Oppo广东移动通信有限公司 | Control method for electronic device, electronic device, and computer-readable storage medium |
| WO2023284317A1 (en) * | 2021-07-16 | 2023-01-19 | 上海禾赛科技有限公司 | Data processing method for laser radar, and laser radar |
| WO2023284319A1 (en) * | 2021-07-16 | 2023-01-19 | 上海禾赛科技有限公司 | Lidar ranging method, lidar and computer-readable storage medium |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20180059224A1 (en) * | 2016-08-26 | 2018-03-01 | Samsung Electronics Co., Ltd. | Time-of-flight (tof) image sensor using amplitude modulation for range measurement |
| CN110221274A (en) * | 2019-05-09 | 2019-09-10 | 深圳奥比中光科技有限公司 | Time flight depth camera and the distance measurement method of multifrequency modulation /demodulation |
| CN110596721A (en) * | 2019-09-19 | 2019-12-20 | 深圳奥锐达科技有限公司 | Flight time distance measuring system and method of double-shared TDC circuit |
| CN110596724A (en) * | 2019-09-19 | 2019-12-20 | 深圳奥锐达科技有限公司 | Method and system for measuring flight time distance during dynamic histogram drawing |
| CN110888140A (en) * | 2018-08-21 | 2020-03-17 | 欧姆龙株式会社 | Distance measuring device and distance measuring method |
-
2020
- 2020-06-22 CN CN202010577154.2A patent/CN111812661A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20180059224A1 (en) * | 2016-08-26 | 2018-03-01 | Samsung Electronics Co., Ltd. | Time-of-flight (tof) image sensor using amplitude modulation for range measurement |
| CN110888140A (en) * | 2018-08-21 | 2020-03-17 | 欧姆龙株式会社 | Distance measuring device and distance measuring method |
| CN110221274A (en) * | 2019-05-09 | 2019-09-10 | 深圳奥比中光科技有限公司 | Time flight depth camera and the distance measurement method of multifrequency modulation /demodulation |
| CN110596721A (en) * | 2019-09-19 | 2019-12-20 | 深圳奥锐达科技有限公司 | Flight time distance measuring system and method of double-shared TDC circuit |
| CN110596724A (en) * | 2019-09-19 | 2019-12-20 | 深圳奥锐达科技有限公司 | Method and system for measuring flight time distance during dynamic histogram drawing |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2022110947A1 (en) * | 2020-11-25 | 2022-06-02 | Oppo广东移动通信有限公司 | Control method for electronic device, electronic device, and computer-readable storage medium |
| CN113075674A (en) * | 2021-03-23 | 2021-07-06 | 深圳市灵明光子科技有限公司 | Ranging method and ranging system based on flight time |
| CN112799097A (en) * | 2021-04-14 | 2021-05-14 | 深圳阜时科技有限公司 | Method for acquiring depth map and gray scale map, depth camera and electronic equipment |
| CN112799097B (en) * | 2021-04-14 | 2023-11-28 | 深圳阜时科技有限公司 | Depth map and gray map acquisition method, depth camera and electronic device |
| CN113504542A (en) * | 2021-07-07 | 2021-10-15 | 奥比中光科技集团股份有限公司 | Distance measuring system and method, device and equipment for calculating reflectivity of measured object |
| CN113504542B (en) * | 2021-07-07 | 2022-10-25 | 奥比中光科技集团股份有限公司 | Distance measuring system and method, device and equipment for calculating reflectivity of measured object |
| WO2023284317A1 (en) * | 2021-07-16 | 2023-01-19 | 上海禾赛科技有限公司 | Data processing method for laser radar, and laser radar |
| WO2023284319A1 (en) * | 2021-07-16 | 2023-01-19 | 上海禾赛科技有限公司 | Lidar ranging method, lidar and computer-readable storage medium |
| CN114494407A (en) * | 2022-04-14 | 2022-05-13 | 宜科(天津)电子有限公司 | Image processing method for distance measurement |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111812661A (en) | Distance measuring method and system | |
| CN110596722B (en) | System and method for measuring flight time distance with adjustable histogram | |
| CN111830530B (en) | Distance measuring method, system and computer readable storage medium | |
| CN110596721B (en) | Flight time distance measuring system and method of double-shared TDC circuit | |
| CN110596725B (en) | Time-of-flight measurement method and system based on interpolation | |
| US11686826B2 (en) | Measuring time-of-flight using a plurality of detector subsystems and histogram storage | |
| CN110596724B (en) | Method and system for measuring flight time distance during dynamic histogram drawing | |
| CN111722241B (en) | Multi-line scanning distance measuring system, method and electronic equipment | |
| CN111487637B (en) | Distance measurement system and method based on time delay | |
| CN111856433B (en) | Distance measuring system and measuring method | |
| CN110596723B (en) | Dynamic histogram drawing flight time distance measuring method and measuring system | |
| CN111856485B (en) | Distance measuring system and measuring method | |
| WO2021244011A1 (en) | Distance measurement method and system, and computer readable storage medium | |
| CN111487638B (en) | Distance measurement system and method based on time delay | |
| CN108139483A (en) | For determining the system and method for the distance of object | |
| CN111796295B (en) | Collector, manufacturing method of collector and distance measuring system | |
| CN111965658B (en) | Distance measurement system, method and computer readable storage medium | |
| CN110780312B (en) | Adjustable distance measuring system and method | |
| CN112346075A (en) | Collector and light spot position tracking method | |
| CN213091889U (en) | Distance measuring system | |
| CN212341461U (en) | Distance measuring system based on time delay | |
| CN111796296A (en) | Distance measuring method, system and computer readable storage medium | |
| CN111965659B (en) | Distance measurement system, method and computer readable storage medium | |
| CN114236504A (en) | dToF-based detection system and light source adjusting method thereof | |
| CN213903798U (en) | Distance measuring system with dual light-emitting modes |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |