WO2019041257A1 - 信号处理芯片、图像处理系统和距离测量系统 - Google Patents

信号处理芯片、图像处理系统和距离测量系统 Download PDF

Info

Publication number
WO2019041257A1
WO2019041257A1 PCT/CN2017/099998 CN2017099998W WO2019041257A1 WO 2019041257 A1 WO2019041257 A1 WO 2019041257A1 CN 2017099998 W CN2017099998 W CN 2017099998W WO 2019041257 A1 WO2019041257 A1 WO 2019041257A1
Authority
WO
WIPO (PCT)
Prior art keywords
processing chip
signal processing
signal
photo
photosensor
Prior art date
Application number
PCT/CN2017/099998
Other languages
English (en)
French (fr)
Inventor
郑国光
洪小平
王铭钰
Original Assignee
深圳市大疆创新科技有限公司
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by 深圳市大疆创新科技有限公司 filed Critical 深圳市大疆创新科技有限公司
Priority to CN201780004561.0A priority Critical patent/CN108513619A/zh
Priority to PCT/CN2017/099998 priority patent/WO2019041257A1/zh
Publication of WO2019041257A1 publication Critical patent/WO2019041257A1/zh

Links

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
    • 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
    • G01S7/491—Details of non-pulse systems
    • G01S7/4912—Receivers
    • 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

Definitions

  • the present application relates to the field of distance detection, and more particularly to a signal processing chip, an image processing system, and a distance measuring system.
  • Distance detection technology is widely used in various fields, such as the field of automatic driving, map mapping, and the field of drones.
  • conventional distance measuring systems In order to be able to detect objects within a certain range, conventional distance measuring systems generally include a scanning mechanism and a rotating mechanism.
  • the rotating mechanism can drive the scanning mechanism to rotate at a fixed frequency (such as 20 Hz).
  • the scanning mechanism is provided with a transmitter and a receiver. During the rotation of the scanning mechanism, the transmitter continuously emits an optical signal (such as a laser signal), and the receiver returns after the optical signal encounters an obstacle (ie, an object to be tested). The reflected signal is detected to determine the distance of the object to be measured.
  • an optical signal such as a laser signal
  • the present application provides a signal processing chip, an image processing system, and a distance measuring system, which can improve the reliability of the distance measuring system and reduce the complexity of the distance measuring system.
  • a signal processing chip comprising: a first photosensor array configured to receive an optical signal and convert the optical signal into a first electrical signal; a first CMOS readout circuit, the first A CMOS readout circuit is configured to receive the first electrical signal, and process the first electrical signal to obtain time data indicative of a time of flight (or reception time) of the optical signal;
  • the first photosensor array is a silicon based photosensor array, and the first photosensor array and the first CMOS readout circuit are integrated on the same silicon wafer.
  • a second aspect provides an image processing system, comprising: the signal processing chip according to the first aspect; a data processor configured to process data output by the signal processing chip to obtain a distance including the object to be tested Image data of the information.
  • a distance measuring system comprising: a transmitter configured to emit an optical signal covering an angle of view FOV of the distance measuring system; the image processing system of the second aspect configured to receive The partial signal reflected by the optical signal after the object to be tested is reflected.
  • the signal processing chip provided by the present application can use the photoelectric sensing array to receive a certain range of optical signals at one time, without using a complicated rotary mechanical mechanism to receive signals in the range as in the conventional distance measuring system, so that Simplify the mechanical structure of the distance measuring system and improve the reliability of the distance measuring system.
  • FIG. 1 is a schematic structural diagram of a distance measuring system according to an embodiment of the present invention.
  • FIG. 2 is a schematic diagram of an optical signal transmission process of a distance measurement system according to an embodiment of the present invention.
  • FIG. 3 is a schematic diagram of an optical signal receiving process of a distance measuring system according to an embodiment of the present invention.
  • FIG. 4 is a diagram showing an example of a planar structure of a signal processing chip according to an embodiment of the present invention.
  • FIG. 5 is a cross-sectional view of a signal processing chip according to an embodiment of the present invention.
  • FIG. 6 is a schematic structural view of an SOI wafer.
  • FIG. 7 is a cross-sectional view of an area of a signal processing chip according to an embodiment of the present invention.
  • FIG. 8 is a diagram showing an example of a circuit configuration of a first photosensor unit and its corresponding readout circuit according to an embodiment of the present invention.
  • FIG. 9 is a cross-sectional view of a signal processing chip according to another embodiment of the present invention.
  • FIG. 10 is a cross-sectional view of a signal processing chip according to still another embodiment of the present invention.
  • FIG. 11 is a diagram showing an example of a planar structure of an area in a signal processing chip according to an embodiment of the present invention.
  • FIG. 12 is a schematic structural diagram of an image processing system according to an embodiment of the present invention.
  • FIG. 13 is a schematic structural diagram of a distance measuring system according to an embodiment of the present invention.
  • the embodiments of the present invention can be applied to various distance measuring systems, such as a light detection and ranging (Lidar) system, and can also be applied to His type of optical signal distance measurement system.
  • Lidar light detection and ranging
  • the embodiment of the present invention provides a distance measurement system based on a photoelectric sensor array.
  • the system structure of the distance measurement system 10 based on the photoelectric sensor array is described below with reference to FIG. 1 .
  • the distance measuring system 10 includes a transmitter 11, an optical signal conditioning system 12, a lens 13, a photosensor array 14, and a data processor 15.
  • the emitter 11 can be used to emit an optical signal (or beam).
  • the optical signal can be used for ranging, and accordingly, the optical signal emitted by the transmitter 11 can also be referred to as a ranging signal.
  • the transmitter 11 can be packaged in a multi-die package such that it provides uniformity in providing optical signals.
  • the type of the transmitter 11 is not specifically limited in the embodiment of the present invention.
  • the emitter 11 can include one or more light emitting diodes (LEDs), laser diodes or infrared emitting diodes, and the like.
  • the transmitter 11 may include a common laser diode or a vertical cavity surface emitting laser (VCSEL).
  • the VCSEL is a surface-emitting type laser, and the wavelength temperature coefficient is small (less than or equal to 1/5 of the temperature coefficient of the ordinary laser wavelength), and is suitable for the distance measuring system 10 based on the photoelectric sensor array provided by the embodiment of the present invention.
  • the wavelength of the optical signal emitted by the transmitter 11 is not specifically limited in the embodiment of the present invention, which is related to the application of the distance measuring system 10.
  • the wavelength of the optical signal emitted by the emitter 11 can include any wavelength between 895 nm and 915 nm.
  • the wavelength of the optical signal emitted by the transmitter 11 can include 905 nm.
  • Optical signal conditioning system 12 can include a laser beam expanding system.
  • the laser beam expanding system can be used to expand the optical signal emitted by the transmitter 11 so that the optical signal can cover an area in the scene to be tested.
  • the laser beam expanding system may be, for example, a reflective beam expanding system, a transmissive beam expanding system, or a combination of the two.
  • the laser beam expanding system may be a first-stage beam expanding system or a multi-stage beam expanding system.
  • a holographic filter can be used to obtain a large angle laser beam composed of a plurality of sub-laser beams.
  • the optical signal emitted by the transmitter 11 may be reflected multiple times using a two-dimensionally adjustable micro-electro-mechanical system (MEMS) micromirror to form a beam-expanded optical signal.
  • MEMS micro-electro-mechanical system
  • the angle between the mirror and the beam can be constantly changed by driving the MEMS micromirror, so that the angle of the optical signal reflected by the MEMS micromirror is constantly changed, thereby diverging into a two-dimensional angle.
  • the beam forms the effect of beam expansion.
  • a beam expander system is provided to directly form a plurality of laser beams using an array of emitters including a plurality of emitters 11, thereby producing a beam expander-like effect.
  • the optical signal conditioning system 12 may further include a device that performs one or more of a process of collimating, homogenizing, and field-of-view (FOV) processing of the optical signal to be emitted or The system makes the outgoing light signal more divergent and more evenly distributed.
  • FOV field-of-view
  • the lens 13 can converge the optical signal reflected by the obstacle (or the object to be tested) to the light incident side of the photosensor array 14 based on the lens imaging principle.
  • the optical signals reflected in different directions may be concentrated to different positions on the light incident side of the photosensor array 14, thereby being received by the photoelectric sensing unit at the corresponding position in the photosensor array 14. Causing an electrical response of the photo-sensing unit to convert the optical signal into an electrical signal.
  • Photoelectric sensing array 14 can be coupled to a complementary metal oxide semiconductor (CMOS) readout circuit (not shown in Figures 1-3).
  • CMOS complementary metal oxide semiconductor
  • the CMOS readout circuitry can be configured to process the electrical signals output by the photosensor array 14 to obtain time data indicative of the time of flight (TOF) of the optical signals emitted by the transmitter 11.
  • TOF time of flight
  • the data processor 15 can determine the distance of the obstacle 20 based on the time of flight of the optical signal emitted by the transmitter 11, thereby obtaining a depth image of the obstacle 20 (or point cloud data with depth information).
  • the distance measuring system 10 provided by the embodiment of the present invention uses the photoelectric sensing array 14 to measure the distance of the object to be tested in the external environment to which the distance measuring system 10 faces. Due to the use of the photo-sensing array 14, the distance measuring system 10 can perform frame-by-frame scanning of the scene to be measured like a camera. Compared with the single-point measurement method of the conventional distance measuring system, the distance measuring system 10 provided by the embodiment of the present invention has a response. Fast speed and high measurement efficiency. Furthermore, the entire measurement process of the distance measuring system 10 can increase the reliability of the distance measuring system without the involvement of rotating components.
  • the main difference between the distance measuring system 10 and the conventional mechanical rotary distance measuring system is that the optical signal reflected by the object to be measured is received or detected by the photoelectric sensing array.
  • the CMOS readout circuit processes the time data for indicating the flight time of the optical signal, and after subsequent data processing, the measured time is calculated.
  • a depth image of an object or point cloud data with depth information.
  • the embodiment of the present invention proposes a scheme in which the photoelectric sensing array and its corresponding CMOS readout circuit are compatible with the same signal processing chip.
  • the signal processing chip will be described in detail below.
  • the signal processing chip described below can be applied to the distance measuring system 10 shown in FIG. 1 and can be applied to any system that needs to measure the time of flight of the optical signal, which is not limited by the embodiment of the present invention. . It will also be understood that the terms “first”, “second”, etc., used hereinafter are used to distinguish different objects, and are not intended to describe a particular order.
  • Embodiments of the present invention provide a signal processing chip, which may include a first photosensor array and a first CMOS readout circuit.
  • the first photosensor array can be configured to receive an optical signal and convert the optical signal into a first electrical signal.
  • the first CMOS readout circuit can be configured to receive the first electrical signal and process the first electrical signal to obtain time data indicative of the time of flight of the optical signal.
  • the first photosensor array is a silicon based photosensor array, and the first photosensor array is integrated with the first CMOS readout circuitry on the same silicon wafer.
  • the first CMOS readout circuit is a circuit fabricated by a silicon-based process (such as a CMOS process or a BiCMOS process).
  • a silicon-based process such as a CMOS process or a BiCMOS process.
  • a photoelectric sensing array is selected as a silicon-based photoelectric sensing array, and the first photoelectric sensing array and the first CMOS sensing circuit are integrated on the same silicon wafer through a silicon-based process (such as a CMOS process or a BiCMOS process).
  • the embodiment of the present invention uses the same silicon-based process to complete the first photo-sensing array and the first CMOS readout circuit in one time, so that the processes of the first photo-sensing array and the first CMOS readout circuit are compatible with each other. This simplifies the process and saves manufacturing costs.
  • the embodiment of the present invention does not limit the type and wavelength of the optical signal received by the first photoelectric sensing array, and may be selected according to actual needs.
  • the optical signal received by the first photosensor array is a laser signal.
  • the optical signal received by the first photosensor array is an optical signal generated by the LED.
  • the wavelength of the optical signal may include any wavelength between 895 nm and 915 nm due to the photoelectric sensing unit of the silicon substrate (or silicon wafer).
  • the peak wavelength of the sensitive wavelength (such as APD or photodiode) will typically be between 900 nm and 1000 nm or between 800 nm and 900 nm.
  • the wavelength of the optical signal can include 905 nm.
  • the embodiment of the present invention does not specifically limit the type of the first photoelectric sensing unit in the first photoelectric sensing array, and may be determined according to the type of the optical signal that the first photoelectric sensing array needs to receive. Taking the optical signal that the first photoelectric sensing array needs to receive as a laser signal, for example, in the first photoelectric sensing array
  • the first photosensor unit may include at least one of an avalanche photodiode (APD) and a silicon photomultiplier (SiPM).
  • the signal processing chip may include an M ⁇ N block region, and each of the regions may include a first photo-sensing unit in the first photo-sensing array, wherein M and N are positive integers of not less than 1, and M ⁇ N is greater than 1.
  • the signal processing chip comprises a total of 15 regions 41 (5 rows and 5 columns), and each of the regions 41 includes a first photosensor unit, thereby forming a 5 ⁇ 5 first photosensor array.
  • the first CMOS readout circuit includes a readout circuit corresponding to each first photosensor unit in the first photosensor array, that is, the first CMOS readout circuit is each first photosensor in the first photosensor array
  • the general name of the readout circuit corresponding to the unit does not specifically limit the arrangement manner of the first photoelectric sensing unit and its corresponding readout circuit, and the first photoelectric sensing unit and its corresponding readout circuit may be located in the same area of the signal processing chip. Can be located in different areas of the signal processing chip.
  • the signal processing chip may include an M x N block area.
  • the first photo-sensing array may include M ⁇ N first photo-sensing units respectively located in the M ⁇ N block region, and the first CMOS readout circuit may include one-to-one correspondence with M ⁇ N first photo-sensing units.
  • M ⁇ N readout circuits, and each of the M ⁇ N readout circuits and the corresponding first photosensor unit are located in the same block region of the M ⁇ N block region, wherein M and N are both Is a positive integer not less than 1, and M ⁇ N is greater than 1.
  • the first photosensor unit and its corresponding readout circuit are disposed in the same area of the signal processing chip, which can simplify the wiring of the chip.
  • the embodiment of the present invention does not specifically limit the arrangement manner of the first photo sensing unit and the readout circuit corresponding to the same area in the area.
  • the first photo sensing unit and the readout circuit corresponding to the same area may be arranged side by side.
  • 5 is a cross-sectional view of the signal processing chip shown in FIG. 4.
  • each of the regions 41 includes a first photo-sensing unit 411 and a readout circuit 412 corresponding to the first photo-sensing unit 411.
  • the first photo sensing unit 411 and the readout circuit 412 are arranged side by side.
  • the first photo sensing unit and the readout circuit corresponding to the same area may be stacked, and the first photo sensing unit and the readout circuit corresponding to the same area may be located at different layers of the signal processing chip.
  • an insulating layer may be disposed between the first photo sensing unit and the readout circuit corresponding to the same region.
  • the insulating layer can be, for example, an oxide layer.
  • the insulating layer can serve as an insulator. Avoid leakage of silicon material and reduce the parasitic capacitance of the chip.
  • the signal processing chip can be designed using an SOI (silicon on insulator) structure.
  • 6 shows the basic structure of an SOI wafer.
  • the SOI wafer may include an upper layer 61, an oxide layer 62, and a bulk handle wafer. 63.
  • the first photo sensing unit 411 can be disposed in the body supporting wafer 63, and the readout circuit 412 corresponding to the first photo sensing unit 411 is disposed in the upper layer 61, thereby making the first photoelectric
  • the sensing unit 411 and its corresponding readout circuit 412 are separated by an insulating layer 62.
  • a transparent spin-on glass may be disposed above the first photo-sensing unit 411 (light incident side), and the SOG is used as a planarization material to enable the first A photoelectric sensing unit 411 is substantially flush with the upper layer 61 above.
  • the embodiment of the present invention does not specifically limit the CMOS readout circuit corresponding to each first photoelectric sensing unit in the first photoelectric sensing array, as long as the CMOS output circuit can output the electricity of the first photoelectric sensing unit.
  • the signal is converted into time data (which can be used to indicate the time of flight of the optical signal received by the first photosensor unit).
  • the readout circuit 412 corresponding to the first photo sensor unit 411 may include a trans-impedance amplifier (TIA) and a time-to-digital converter (TDC).
  • TIA trans-impedance amplifier
  • TDC time-to-digital converter
  • the TDC may sample the reception time of the optical signal received by the first photo sensing unit 411 based on the voltage signal to obtain digitized time data.
  • the TDC can also be replaced with other devices or circuits that enable similar time measurement functions, such as analog to digital converter (ADC) or digital signal processing (DSP).
  • ADC analog to digital converter
  • DSP digital signal processing
  • the above correspondence between the first photo sensing unit and the CMOS readout circuit is a logical or functional division.
  • the readout circuits corresponding to different first photosensor units may be independent of each other, or some devices may be shared.
  • each first photo-sensing unit in the first photo-sensing array may correspond to one TDC, or a plurality of first photo-sensing units in the first photo-sensing array may share one TDC.
  • the first photo-sensing array may include N columns of first photo-sensing units
  • the first CMOS readout circuit may include N TDCs corresponding to the N-column first photo-sensing units.
  • the N TDCs are configured to process the optical signals received by the N-column first photo-sensing unit, respectively, where N is a positive integer not less than one.
  • N is a positive integer not less than one.
  • each column of the first photo-sensing unit shares a TDC, which simplifies the chip structure. Save on the manufacturing cost of the chip.
  • each of the regions 41 in FIG. 4 may be referred to as one pixel, and all of the regions 41 form a pixel array.
  • a row selection circuit 42 and a column selection circuit 43 may be included in the signal processing chip.
  • a row in the pixel array can be selected by the row selection circuit 42, and a column in the pixel array can be selected by the column selection circuit 43.
  • the row selection circuit 42 and the column selection circuit 43 operate simultaneously, and a pixel in the pixel array can be gated for data output.
  • the signal processing chip may further include an optical filter.
  • the optical filter can be, for example, a filter.
  • An optical filter may be disposed on a light incident side of the first photosensor array, and the optical filter may be configured to filter an optical signal incident to the first photosensor array to obtain an optical signal of a target wavelength.
  • the optical filter can select the incident light to filter out the light of the incident light that does not meet the required wavelength before the incident light reaches the first photoelectric sensing array, and obtain the optical signal of the target wavelength. Assuming that the target wavelength of the first sensing unit in the first photosensor array is around 905 nm, the parameters of the optical filter can be adjusted so that the wavelength of the optical filter is allowed to pass around 905 nm (the error range can be +/). -10 nm), thereby reducing the interference of other light rays on the first photosensor array.
  • the signal processing chip may further comprise an anti-reflection film.
  • the antireflection film may be disposed on the light incident side of the optical filter.
  • the embodiment of the present invention provides an antireflection film on the light incident side of the optical filter.
  • the anti-reflection film arrangement can increase the transmittance of the optical signal, thereby improving the signal detection performance of the first photo-sensing array.
  • the thickness of the anti-reflection film is related to the type of the optical signal to be received, which is not specifically limited in the embodiment of the present invention. Taking the optical signal to be received as a laser signal as an example, the thickness of the antireflection film may be 1/4 of the wavelength of the laser signal, and the error range may be selected as +/- 10%.
  • a sheet layer 901 may be added on the light incident side of the first photosensor array, and the sheet layer 901 may include an antireflection film and/or an optical filter.
  • the signal processing chip may further include a lens, and the lens may be disposed on a light incident side of the L first photo sensing units in the first photosensor array, and the lens may be used to inject into the L The light rays of the optical signals of the first photoelectric sensing units are concentrated, wherein L is a positive integer not less than one.
  • each of the first photoelectric sensing units in the first photoelectric sensing array may be provided with a lens, or may be a part of the first photoelectricity in the first photoelectric sensing array.
  • the sensing unit is provided with a lens.
  • the incident light rays of the L first photosensor units can be concentrated, thereby improving the detection sensitivity of the L first photosensor units. Further, due to the presence of the lens, the incident light rays reaching the L first photo sensing units are concentrated to the light incident side of the L first photo sensing units, and are not refracted to the adjacent first phototransmission Sensing unit, thereby reducing cross-talk between the first photo-sensing units.
  • a lens 1001 can be disposed above each layer 901 for each photosensor unit in the first photosensor array.
  • the size of the lens 1001 may be selected based on the size of the first photo sensing unit corresponding to the lens 1001.
  • lens 1001 can be sized to substantially cover a first photosensor unit beneath the lens.
  • FIG. 10 is exemplified by providing a sheet layer 901 (including an anti-reflection film and/or an optical filter) on the light incident side of the first photosensor array, and arranging the lens 1001 as an example, but the present invention is implemented.
  • the example is not limited to this.
  • the lens 1001 can be placed in the light of the first photosensor array without the sheet layer 901 being disposed.
  • the signal processing chip may further include: a second photo sensing array and a second CMOS readout circuit.
  • the second photosensor array can be configured to receive a mixed signal comprising the optical signal and the ambient light to convert the mixed signal into a second electrical signal;
  • the second CMOS readout circuit can be configured to receive the second electrical signal, to the second The electrical signal is processed to obtain colored or black-and-white pixel data.
  • the second photosensor array may comprise a plurality of second photosensor units, which may be, for example, a CMOS image sensor (CIS).
  • CIS CMOS image sensor
  • the signal processing chip provided by the embodiment of the invention comprises a first photoelectric sensing array and a second photoelectric sensing array.
  • the first photosensor array can receive an optical signal for ranging to form a depth image
  • the second photosensor array can be used to receive ambient light to form a color image.
  • two frames of images can be obtained for each signal acquisition of the environment to be tested, and one frame of image records the depth information (or distance information) of the environment to be tested.
  • the other frame image records the color (color or black and white) information of the environment to be tested.
  • the signal processing chip may include an M ⁇ N block region
  • the first photoelectric sensing array may include M ⁇ N first photoelectric sensing units respectively located in the M ⁇ N block region
  • the two photosensor arrays may include M ⁇ N second photosensor units respectively located in the M ⁇ N block region, wherein M and N are positive integers not less than 1, and M ⁇ N is greater than 1.
  • Each of the M ⁇ N block regions includes both a first photo-sensing unit and a second photo-sensing unit, and a depth image having M ⁇ N pixels can be obtained based on the first photo-sensing array, based on the second
  • the photoelectric sensing array can obtain a color image having M ⁇ N pixels, and since the first photoelectric sensing unit and the second photoelectric sensing unit are located in the same region, the pixels in the depth image and the color image have a one-to-one correspondence. That is, the corresponding pixels in the depth image and the color image respectively describe the depth information and the color information of substantially the same orientation in the environment to be tested, simplifying or even eliminating the registration process of the subsequent two frames of images.
  • the second photo sensing unit may include one or more sets of RGB pixels. Further, in each group of RGB pixels, each color may correspond to one pixel or may correspond to a plurality of pixels.
  • each set of RGB pixels may include 2 green pixels (pixels capable of strobing green light), 1 red pixel (pixel capable of strobing red light), and 1 blue pixel (pixel capable of strobing blue light).
  • the image data generated by the RGB pixels is color image data.
  • the pixels in the second photo sensing unit may also be black and white pixels. Accordingly, the generated image data may be black and white image data.
  • the positions of the first photo sensing unit and the second photo sensing unit corresponding to each of the M ⁇ N block regions in each of the regions may not overlap each other.
  • each of the block regions 41 in the M ⁇ N block region may include a first sub-region 1101 and a second sub-region 1102 that do not overlap each other.
  • the first photo-sensing unit 411 corresponding to each of the regions 41 is located in the first sub-region 1101, and the second photo-sensing unit 413 corresponding to each of the regions 41 is located in the second sub-region 1102.
  • region 41 may also include a third sub-region 1103.
  • the readout circuit 412 corresponding to the first photo sensing unit 411 in the first sub-region 1101 may be located in the third sub-region 1103.
  • the readout circuit 412 corresponding to the first photo sensing unit 411 in the first sub-region 1101 may also be located in the first sub-region 1101 and/or the second sub-region 1102, and the first The photo-sensing unit 411 and/or the second photo-sensing unit 413 are disposed at different layers.
  • the above embodiment describes the planar layout of the first photosensor unit and the second photosensor unit in the same area.
  • the first photo sensing unit and the second photo sensing unit in the same area may be located in the same layer of the signal processing chip, or may be located in different layers of the signal processing chip.
  • the first photo sensing unit and the second photo sensing unit may be isolated from each other to prevent between the first photo sensing unit and the second photo sensing unit in the same region. affect each other.
  • the APD is a high voltage device, and the APD interferes with the CIS during operation, and the interference between the two can effectively reduce the interference between the two. Improve the accuracy of the chip.
  • the first photo-sensing unit and the second photo-sensing unit in the same region are located in the same layer of the signal processing chip, and the first photo-sensing unit and the second photo-sensing unit are isolated from each other.
  • an insulating material may be added between the first photo-sensing unit and the second photo-sensing unit in the same layer.
  • first photo sensing unit and the second photo sensing unit in the same region may be located at different layers of the signal processing chip, and the first photo sensing unit and the second photo sensing unit are disposed There is insulation.
  • the second photo-sensing unit 413 may be disposed on the upper layer 61 of the SOI structure to isolate the first photo-sensing unit 411 and the second photo-sensing unit 413 from each other through the oxide layer 62.
  • the positions of the first photo sensing unit 411 and the second photo sensing unit 413 in FIG. 7 may also be interchanged, and the first photo sensing unit in the same area may also be used. The effect of being isolated from the second photo-sensing unit.
  • the light incident side of at least one of the first photosensor unit and the second photosensor unit corresponding to the same region is provided with a light transmissive insulating material.
  • the SOG 64 is disposed above the first photo-sensing unit 411.
  • the SOG 64 is a light-transmitting insulating material, which can ensure that the first photo-sensing unit 411 of the lower layer receives the incident light, and It is possible to ensure that the first photo sensing unit 411 and the second photo sensing unit 413 are isolated from each other.
  • the image processing system 1200 can include a signal processing chip 1210 and a data processor 1220.
  • the signal processing chip 1210 may be the signal processing chip described in any of the preceding embodiments.
  • Data processor 1220 can be configured to The data output from the signal processing chip 1210 is processed to obtain a depth image (or point cloud data with depth information) containing the object to be measured.
  • the data processor 1220 may acquire time data indicating the transmission time of the optical signal from the transmitting end of the optical signal, and receive a flight time for indicating the optical signal from the first CMOS readout circuit in the image processing chip 1210.
  • the data processor 1220 can generate a depth image of the object to be tested by using the TOF principle according to the time of flight of the optical signal. Further, when the signal processing chip 1210 includes the second photo sensing array and the second CMOS readout circuit, the data processor 1220 may further generate the object to be tested according to the black and white or color image data output by the second CMOS readout circuit. Black and white or color images.
  • the embodiment of the invention also provides a distance measuring system.
  • the distance measurement system 1300 can include a transmitter 1310 and an image processing system 1200 as shown in FIG.
  • Transmitter 1310 can be configured to emit an optical signal, such as an optical signal that emits an FOV that covers distance measurement system 1300.
  • Image processing system 1300 can be configured to receive a portion of the signal that is reflected back after the optical signal encounters the object to be measured.
  • the distance measurement system 1300 can be a laser detection and measurement system, or laser radar.
  • the distance measuring system is used to sense external environmental information, such as distance information of an environmental target, angle information, reflection intensity information, speed information, and the like.
  • the laser measurement system of the embodiment of the present invention is applicable to a mobile platform, and the laser measurement system can be installed on a platform body of the mobile platform.
  • a mobile platform with a laser measurement system can measure the external environment, for example, measuring the distance between the mobile platform and obstacles for obstacle avoidance, and two-dimensional or three-dimensional mapping of the external environment.
  • the mobile platform includes at least one of an unmanned aerial vehicle, a car, and a remote control car.
  • the laser measurement system is applied to an unmanned aerial vehicle
  • the platform body is the body of the unmanned aerial vehicle.
  • the platform body is the body of the car.
  • the laser measuring system is applied to a remote control car
  • the platform body is the body of the remote control car.
  • the computer program product includes one or more computer instructions.
  • the computer can be a general purpose computer, a special purpose computer, a computer network, or other programmable device.
  • the computer instructions can be stored in a computer readable storage medium or transferred from one computer readable storage medium to another computer readable storage medium, for example,
  • the computer instructions may be from a website site, computer, server or data center via a wired (eg, coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (eg, infrared, wireless, microwave, etc.) Another website site, computer, server, or data center for transmission.
  • the computer readable storage medium can be any available media that can be accessed by a computer or a data storage device such as a server, data center, or the like that includes one or more available media.
  • the usable medium may be a magnetic medium (for example, a floppy disk, a hard disk, a magnetic tape), an optical medium (such as a digital video disc (DVD)), or a semiconductor medium (such as a solid state disk (SSD)).
  • a magnetic medium for example, a floppy disk, a hard disk, a magnetic tape
  • an optical medium such as a digital video disc (DVD)
  • a semiconductor medium such as a solid state disk (SSD)
  • the disclosed systems, devices, and methods may be implemented in other manners.
  • the device embodiments described above are merely illustrative.
  • the division of the unit is only a logical function division.
  • there may be another division manner for example, multiple units or components may be combined or Can be integrated into another system, or some features can be ignored or not executed.
  • the mutual coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection through some interface, device or unit, and may be in an electrical, mechanical or other form.
  • the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, may be located in one place, or may be distributed to multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of the embodiment.
  • each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • General Physics & Mathematics (AREA)
  • Radar, Positioning & Navigation (AREA)
  • Remote Sensing (AREA)
  • Electromagnetism (AREA)
  • Solid State Image Pick-Up Elements (AREA)
  • Optical Radar Systems And Details Thereof (AREA)

Abstract

提供一种信号处理芯片、图像处理系统和距离测量系统。该信号处理芯片包括：第一光电传感阵列，被配置成接收光信号，并将光信号转换成第一电信号；第一CMOS读出电路，第一CMOS读出电路被配置成接收第一电信号，对第一电信号进行处理，以获取用于指示光信号的飞行时间的时间数据；其中第一光电传感阵列为硅基的光电传感阵列，且第一光电传感阵列与第一CMOS读出电路集成在同一硅晶圆上。采用光电传感阵列接收光信号，能够降低距离测量系统的复杂度，提高距离测量系统的可靠性。

Description

信号处理芯片、图像处理系统和距离测量系统
版权申明
本专利文件披露的内容包含受版权保护的材料。该版权为版权所有人所有。版权所有人不反对任何人复制专利与商标局的官方记录和档案中所存在的该专利文件或者该专利披露。
技术领域
本申请涉及距离探测领域，更为具体地，涉及一种信号处理芯片、图像处理系统和距离测量系统。
背景技术
距离探测技术广泛应用于各个领域，如自动驾驶领域、地图测绘领域以及无人机领域。
为了能够对一定范围内的物体进行探测，传统的距离测量系统一般包括扫描机构和旋转机构。旋转机构能够带动扫描机构以固定频率(如20Hz)旋转。扫描机构中设置有发射器和接收器，在扫描机构的旋转过程中，发射器不断发出光信号(如激光信号)，接收器对该光信号遇到障碍物(即待测物体)之后返回的反射信号进行检测，从而确定待测物体的距离。
传统距离测量系统具有复杂的机械结构，并设置有旋转机构，导致传统距离测量系统的可靠性低。
发明内容
本申请提供一种信号处理芯片、图像处理系统和距离测量系统，能够提高距离测量系统的可靠性，并降低距离测量系统的复杂度。
第一方面，提供一种信号处理芯片，包括：第一光电传感阵列，被配置成接收光信号，并将所述光信号转换成第一电信号；第一CMOS读出电路，所述第一CMOS读出电路被配置成接收所述第一电信号，对所述第一电信号进行处理，以获取用于指示所述光信号的飞行时间(或接收时间)的时间数据；其中所述第一光电传感阵列为硅基的光电传感阵列，且所述第一光电传感阵列与所述第一CMOS读出电路集成在同一硅晶圆上。
第二方面，提供一种图像处理系统，包括：如第一方面所述的信号处理芯片；数据处理器，被配置成对所述信号处理芯片输出的数据进行处理，得到包含待测物体的距离信息的图像数据。
第三方面，提供一种距离测量系统，包括：发射器，被配置成发射覆盖所述距离测量系统的视场角FOV的光信号；如第二方面所述的图像处理系统，被配置成接收所述光信号遇到所述待测物体后反射回来的部分信号。
本申请提供的信号处理芯片采用光电传感阵列可以一次性接收一定范围内的光信号，而无需像传统距离测量系统那样利用复杂的旋转式机械机构对该范围内的信号进行接收，这样不但能够简化距离测量系统的机械结构，而且可以提高距离测量系统的可靠性。
附图说明
图1是本发明实施例提供的距离测量系统的示意性结构图。
图2是本发明实施例提供的距离测量系统的光信号发射过程的示意图。
图3是本发明实施例提供的距离测量系统的光信号接收过程的示意图。
图4是本发明实施例提供的信号处理芯片的平面结构示例图。
图5是本发明一个实施例提供的信号处理芯片的剖视图。
图6是SOI晶圆的结构示意图。
图7是本发明实施例提供的信号处理芯片中的一块区域的剖视图。
图8是本发明实施例提供的第一光电传感单元及其对应的读出电路的电路结构示例图。
图9是本发明另一实施例提供的信号处理芯片的剖视图。
图10是本发明又一实施例提供的信号处理芯片的剖视图。
图11是本发明实施例提供的信号处理芯片中的一块区域的平面结构示例图。
图12是本发明实施例提供的图像处理系统的示意性结构图。
图13是本发明实施例提供的距离测量系统的示意性结构图。
具体实施方式
本发明实施例可应用于各种距离测量系统，如可应用于激光探测与测量(light detection and ranging，Lidar)系统，也可应用于基于除激光之外的其 他类型的光信号的距离测量系统。
为了简化距离测量系统的结构，提高距离测量系统的可靠性。本发明实施例提供一种基于光电传感阵列的距离测量系统，下面结合图1，对基于光电传感阵列的距离测量系统10的系统结构进行举例描述。
如图1所示，距离测量系统10包含发射器11，光信号调节系统12，透镜13，光电传感阵列14以及数据处理器15。
发射器11可用于发射光信号(或称光束)。该光信号可用于测距，相应地，发射器11发出的光信号也可称为测距信号。发射器11可以采用多晶粒(multi-die)封装，这样有利用提供光信号的均匀性。
本发明实施例对发射器11的类型不做具体限定。在一些实施例中，发射器11可以包括一个或多个发光二极管(light emitting diode，LED)，激光二极管或红外发射二极管等。以Lidar系统为例，发射器11可以包括普通的激光二极管，也可以包括垂直腔面发射激光器(vertical cavity surface emitting laser，VCSEL)。VCSEL是一种面发射型激光器，且波长温度系数小(小于或等于普通激光器波长温度系数的1/5)的特点，比较适合本发明实施例提供的基于光电传感阵列的距离测量系统10。
本发明实施例对发射器11发出的光信号的波长不做具体限定，这与距离测量系统10的应用场合有关。在一些实施例中，发射器11发出的光信号的波长可以包括895nm至915nm之间的任一波长。在一些实施例中，发射器11发出的光信号的波长可以包括905nm。
光信号调节系统12可包括激光扩束系统。激光扩束系统可用于对发射器11发出的光信号进行扩束，从而使得光信号能够覆盖待测场景中的一块区域。激光扩束系统例如可以是反射式扩束系统，也可以是透射式扩束系统，还可以是二者的组合。此外，激光扩束系统可以是一级扩束系统，也可以是多级扩束系统。作为一个示例，可以使用全息滤波器(holographic filter)得到多个子激光束组成的大角度激光束。作为另一个示例，可以利用二维角度可调的微机电系统(micro-electro-mechanical system，MEMS)微镜对发射器11发出的光信号进行多次反射，从而形成扩束后的光信号。具体地，在发射器11发出光信号之后，可以通过驱动MEMS微镜不断改变自身镜面与光束间的角度，使得MEMS微镜反射出的光信号的角度不断变化，从而发散成具有二维角度的光束，形成扩束的效果。当然，在一些实施例中，也可以不 设置扩束系统，直接利用包含多个发射器11的发射器阵列形成多束激光，从而产生类似扩束的效果。
进一步地，在一些实施例中，光信号调节系统12还可包括对待出射的光信号执行准直、匀光以及扩视场角(fieldangle，FOV)等处理中的一种或多种的器件或系统，使得出射的光信号更加发散，分布更加均匀。以图2为例，经过光信号调节系统12的处理，距离测量系统10向外发出的光信号具有较大的覆盖范围。
透镜13可基于透镜成像原理，将障碍物(或待测物体)反射回来的光信号汇聚至光电传感阵列14的光入射侧。从图3可以看出，不同方向反射回来的光信号可能会被汇聚至光电传感阵列14的光入射侧的不同位置，从而被光电传感阵列14中的处于相应位置的光电传感单元接收，引起该光电传感单元的光电响应，从而将光信号转换成电信号。
光电传感阵列14可以与互补金属氧化物半导体(complementary metal oxide semiconductor，CMOS)读出电路(图1-3中未示出)相连。CMOS读出电路可被配置成对光电传感阵列14输出的电信号进行处理，以获取用于指示发射器11发出的光信号的飞行时间(time of flight，TOF)的时间数据。
数据处理器15可根据发射器11发出的光信号的飞行时间，确定障碍物20的距离，进而得到障碍物20的深度图像(或具有深度信息的点云数据)。
从图1-3的描述可以看出，本发明实施例提供的距离测量系统10采用光电传感阵列14对该距离测量系统10所面向的外界环境中的待测物体的距离进行测量。由于光电传感阵列14的使用，距离测量系统10可以像相机一样对待测场景进行逐帧扫描，与传统距离测量系统的单点测量方式相比，本发明实施例提供的距离测量系统10具有响应速度快，测量效率高的特点。此外，距离测量系统10的整个测量过程可以无需旋转部件的参与，提高了距离测量系统的可靠性。
距离测量系统10与传统的机械旋转式的距离测量系统相比，主要的不同之处在于使用光电传感阵列对待测物体反射回的光信号进行接收或检测。光电传感阵列将接收到的光信号转换成电信号之后，经过CMOS读出电路处理，可以得到用于指示光信号的飞行时间的时间数据，再经过后续数据处理之后，即可计算出待测物体的深度图像(或具有深度信息的点云数据)。为了简化光电传感阵列及其对应的CMOS读出电路的制造过程，节约制造 成本，本发明实施例提出一种可以将光电传感阵列及其对应的CMOS读出电路兼容在同一信号处理芯片的方案。下面对该信号处理芯片进行详细描述。应理解，下文描述的信号处理芯片可应用于图1所示的距离测量系统10中，也可应用于其他需要对光信号的飞行时间进行测量的任意系统，本发明实施例对此并不限定。还应理解，下文中使用的术语“第一”、“第二”等是用于区别不同的对象，而不是用于描述特定的顺序。
本发明实施例提供一种信号处理芯片，该信号处理芯片可包含第一光电传感阵列和第一CMOS读出电路。第一光电传感阵列可被配置成接收光信号，并将光信号转换成第一电信号。第一CMOS读出电路可被配置成接收第一电信号，对第一电信号进行处理，以获取用于指示光信号的飞行时间的时间数据。第一光电传感阵列为硅基的光电传感阵列，且第一光电传感阵列与第一CMOS读出电路集成在同一硅晶圆上。
第一CMOS读出电路是通过硅基工艺(如CMOS工艺或BiCMOS工艺)制造的电路，为了将第一光电传感阵列与第一CMOS读出电路集成在同一芯片中，本发明实施例将第一光电传感阵列选取为硅基的光电传感阵列，并将第一光电传感阵列与第一CMOS读出电路均通过硅基工艺(如CMOS工艺或BiCMOS工艺)集成在同一硅晶圆上。也就是说，本发明实施例采用同一硅基工艺将第一光电传感阵列和第一CMOS读出电路一次性加工完成，使得第一光电传感阵列和第一CMOS读出电路的工艺相互兼容，从而可以简化工艺流程，节约制造成本。
本发明实施例对第一光电传感阵列接收到的光信号的类型和波长不做限定，可以根据实际需要选择。作为一个示例，第一光电传感阵列接收到的光信号为激光信号。作为另一个示例，第一光电传感阵列接收到的光信号为LED生成的光信号。以第一光电传感阵列接收到的光信号为激光信号为例，光信号的波长可以包括895nm至915nm之间的任一波长，这是由于硅基底(或硅晶圆)的光电传感单元(如APD或光电二极管)的敏感波长的峰值通常会在900nm-1000nm之间或在800nm-900nm之间。在一些实施例中，该光信号的波长可以包括905nm。
本发明实施例对第一光电传感阵列中的第一光电传感单元的类型不做具体限定，可以根据第一光电传感阵列需要接收的光信号的类型确定。以第一光电传感阵列需要接收的光信号为激光信号为例，第一光电传感阵列中的 第一光电传感单元可以包含雪崩光电二极管(avalanche Photo Diode，APD)和硅光电倍增管(Silicon photomultiplier，SiPM)中的至少一种。
本发明实施例对第一光电传感阵列的排布方式不做具体限定。作为一个示例，信号处理芯片可以包括M×N块区域，每块区域可以包含第一光电传感阵列中的一个第一光电传感单元，其中M、N均为不小于1的正整数，且M×N大于1。以图4为例，信号处理芯片共包含15块区域41(5行5列)，每块区域41包含一个第一光电传感单元，从而形成了5×5的第一光电传感阵列。
第一CMOS读出电路包含第一光电传感阵列中的各第一光电传感单元对应的读出电路，即第一CMOS读出电路为第一光电传感阵列中的各第一光电传感单元对应的读出电路的总称。本发明实施例对第一光电传感单元及其对应的读出电路的排布方式不做具体限定，第一光电传感单元与其对应的读出电路可以均位于信号处理芯片的同一区域，也可以位于信号处理芯片的不同区域。
可选地，作为一个实施例，信号处理芯片可以包含M×N块区域。第一光电传感阵列可以包含分别位于M×N块区域中的M×N个第一光电传感单元，第一CMOS读出电路可以包含与M×N个第一光电传感单元一一对应的M×N个读出电路，且M×N个读出电路中的每个读出电路与对应的第一光电传感单元位于M×N块区域的同一块区域中，其中M、N均为不小于1的正整数，且M×N大于1。本发明实施例将第一光电传感单元与其对应的读出电路设置在信号处理芯片的同一区域中，可以简化芯片的布线。
本发明实施例对同一区域对应的第一光电传感单元和读出电路在该区域中的排布方式不做具体限定。
作为一个示例，同一区域对应的第一光电传感单元和读出电路可以并列设置。图5是图4所示的信号处理芯片的截面图，在图5的示例中，每块区域41包含第一光电传感单元411以及该第一光电传感单元411对应的读出电路412，且第一光电传感单元411和读出电路412并列设置。
作为另一个示例，同一区域对应的第一光电传感单元和读出电路可以堆叠设置，如同一区域对应的第一光电传感单元和读出电路可以位于信号处理芯片的不同层。进一步地，同一区域对应的第一光电传感单元和读出电路之间可以设置绝缘层。绝缘层例如可以是氧化层。绝缘层可以起到隔离作用， 避免硅材料的漏电现象，并减少芯片的寄生电容。
例如，信号处理芯片可以采用SOI(silicon on insulator，绝缘衬底上的硅)结构设计。图6示出了SOI晶圆(wafer)的基本结构，如图6所示，SOI晶圆可以包括上层(upper layer)61、氧化层(oxide layer)62和体支撑晶圆(bulk handle wafer)63。如图7所示，可以将第一光电传感单元411设置在体支撑晶圆63中，将该第一光电传感单元411对应的读出电路412设置在上层61中，从而使得第一光电传感单元411及其对应的读出电路412通过绝缘层62相隔。进一步地，在一些实施例中，可以在第一光电传感单元411的上方(光入射侧)设置一层透明的旋涂玻璃(spin on glass，SOG)，SOG作为平坦化材料，能够使得第一光电传感单元411上方与上层61基本保持平齐。
本发明实施例对第一光电传感阵列中的每个第一光电传感单元对应的CMOS读出电路形式不做具体限定，只要该CMOS输出电路能够将该第一光电传感单元输出的电信号转换成时间数据(可用于指示该第一光电传感单元接收到的光信号的飞行时间)即可。如图8所示，该第一光电传感单元411对应的读出电路412可以包括跨阻放大器(trans-impedance amplifier，TIA)和时间数字转换器(time-to-digital converter，TDC)。TIA可用于将第一光电传感单元411输出的微弱的电流信号转换成稳定的电压信号。TDC可基于该电压信号对第一光电传感单元411接收到的光信号的接收时间进行采样，得到数字化的时间数据。在一些实施例中，TDC还可以替换为其他能够实现类似的时间测量功能的器件或电路，如模数转换器(analog to digital converter，ADC)或数字信号处理(digital signal processing，DSP)。
需要说明的是，第一光电传感单元和CMOS读出电路的上述对应关系是一种逻辑或功能上的划分。实际上，不同第一光电传感单元对应的读出电路可以相互独立，也可以共用一些器件。例如，第一光电传感阵列中的每个第一光电传感单元可对应一个TDC，或者，第一光电传感阵列中的多个第一光电传感单元可以共用一个TDC。可选地，作为一个示例，第一光电传感阵列可以包含N列第一光电传感单元，第一CMOS读出电路可以包含与N列第一光电传感单元一一对应的N个TDC，N个TDC被配置成分别处理N列第一光电传感单元接收到的光信号，其中N为不小于1的正整数。换句话说，在该示例中，每列第一光电传感单元共用一个TDC，这样可以简化芯片结构， 节约芯片的制造成本。
继续参见图4，图4中的每块区域41可以称为一个像素，所有的区域41形成像素阵列。在信号处理芯片中，除了上述第一光电传感阵列和第一CMOS读出电路之外，还可以包括行选择电路42和列选择电路43。通过行选择电路42可以选取像素阵列中的某一行，通过列选择电路43可以选取像素阵列中的某一列。行选择电路42和列选择电路43同时工作，可以选通像素阵列中的某一像素进行数据输出。
可选地，在一些实施例中，信号处理芯片还可包含光滤波器(optical filter)。光滤波器例如可以是滤光片。光滤波器可设置在第一光电传感阵列的光入射侧，光滤波器可被配置成对入射至第一光电传感阵列的光信号进行滤波，以得到目标波长的光信号。
光滤波器可以对入射光线进行选择，从而在入射光线到达第一光电传感阵列之前，滤掉入射光线中的波长不符合要求的光线，得到目标波长的光信号。假设第一光电传感阵列中的第一传感单元期望的目标波长在905nm左右，可以通过调整光滤波器的参数，使得允许通过该光滤波器的波长在905nm左右(误差范围可以是+/-10nm)，从而降低其他光线对第一光电传感阵列的干扰。
进一步地，在一些实施例中，信号处理芯片还可包含增透膜。增透膜可以设置在光滤波器的光入射侧。
入射光线经过光滤波器之后，会产生部分反射光线，为了减少反射光线，本发明实施例在光滤波器的光入射侧设置了增透膜。增透膜的设置可以增加光信号的透过率，从而提高第一光电传感阵列的信号检测性能。
增透膜的厚度与待接收的光信号的类型有关，本发明实施例对此不做具体限定。以待接收的光信号为激光信号为例，增透膜的厚度可以是激光信号波长的1/4，误差范围可以选取为+/-10％。
具体地，如图9所示，可以在第一光电传感阵列的光入射侧添加片层901，该片层901可以包含增透膜和/或光滤波器。
可选地，在一些实施例中，信号处理芯片还可包括透镜，透镜可设置在第一光电传感阵列中的L个第一光电传感单元的光入射侧，透镜可用于对入射至L个第一光电传感单元的光信号的光线进行汇聚，其中L为不小于1的正整数。
本发明实施例对L的取值不做具体限定，可以为第一光电传感阵列中的各第一光电传感单元均设置透镜，也可以为第一光电传感阵列中的部分第一光电传感单元设置透镜。
通过在L个第一光电传感单元的光入射侧设置透镜，可以对该L个第一光电传感单元的入射光线进行汇聚，从而提高该L个第一光电传感单元的检测灵敏度。进一步地，由于透镜的存在，到达该L个第一光电传感单元的入射光线均会被汇聚至该L个第一光电传感单元的光入射侧，不会折射到相邻第一光电传感单元，从而降低第一光电传感单元之间的相互干扰(cross-talk)。
以图10为例，可以在片层901的上方为第一光电传感阵列中的每个光电传感单元设置一个透镜1001。透镜1001的尺寸可以基于该透镜1001对应的第一光电传感单元的尺寸选取。例如，透镜1001的尺寸可以配置为基本覆盖该透镜下方的第一光电传感单元。
应理解，图10是以第一光电传感阵列的光入射侧既设置片层901(包含增透膜和/或光滤波器)，又设置透镜1001为例进行举例说明的，但本发明实施例不限于此。例如，在一些实施例中，可以在第一光电传感阵列的光入射设置透镜1001，而不设置片层901。
可选地，在一些实施例中，信号处理芯片还可包括：第二光电传感阵列和第二CMOS读出电路。第二光电传感阵列可被配置成接收包含光信号和环境光的混合信号，将混合信号转换成第二电信号；第二CMOS读出电路可被配置成接收第二电信号，对第二电信号进行处理，得到彩色的或黑白的像素数据。
第二光电传感阵列可以包含多个第二光电传感单元，该第二光电传感单元例如可以是CMOS图像传感器(CMOS image sensor，CIS)。
本发明实施例提供的信号处理芯片包含第一光电传感阵列和第二光电传感阵列。第一光电传感阵列可接收用于测距的光信号，从而形成深度图像，第二光电传感阵列可用于接收环境光，从而形成颜色图像。换句话说，在本发明实施例提供的信号处理芯片的基础上，对待测环境的每次信号采集可以得到两帧图像，一帧图像记录的是待测环境的深度信息(或距离信息)，另一帧图像记录的是待测环境的颜色(彩色或黑白)信息。
下面对第一光电传感阵列和第二光电传感阵列的排布方式进行详细介 绍。
可选地，在一些实施例中，信号处理芯片可以包含M×N块区域，第一光电传感阵列可以包含分别位于M×N块区域中的M×N个第一光电传感单元，第二光电传感阵列可以包含分别位于M×N块区域中的M×N个第二光电传感单元，其中M、N均为不小于1的正整数，且M×N大于1。
M×N块区域中的每块区域既包含第一光电传感单元，又包含第二光电传感单元，基于第一光电传感阵列可以得到具有M×N个像素的深度图像，基于第二光电传感阵列可以得到具有M×N个像素的颜色图像，且由于第一光电传感单元和第二光电传感单元位于同一区域，该深度图像和颜色图像中的像素天然具有一一对应性，即深度图像和颜色图像中的对应像素分别描述的是待测环境中的大致同一方位的深度信息和颜色信息，简化甚至无需后续两帧图像的配准过程。
以第二光电传感单元为CIS单元为例，第二光电传感单元可以包含一组或多组RGB像素。进一步地，在每组RGB像素中，每个颜色可以对应一个像素也可以对应多个像素。例如，每组RGB像素可以包含2个绿色像素(能够选通绿光的像素)，1个红像素(能够选通红光的像素)和1个蓝色像素(能够选通蓝光的像素)。采用RGB像素生成的图像数据为彩色图像数据，可替换地，在一些实施例中，第二光电传感单元中的像素也可以是黑白像素，相应地，生成的图像数据可以为黑白图像数据。
M×N块区域中的每块区域对应的第一光电传感单元和第二光电传感单元在该每块区域中的位置可以互不重叠。
具体地，参见图11，M×N块区域中的每块区域41可以包含互不重叠的第一子区域1101和第二子区域1102。每块区域41对应的第一光电传感单元411位于第一子区域1101中，每块区域41对应的第二光电传感单元413位于第二子区域1102中。
进一步地，在一些实施例中，区域41还可包含第三子区域1103。第一子区域1101中的第一光电传感单元411对应的读出电路412可位于该第三子区域1103中。当然，在一些实施例中，第一子区域1101中的第一光电传感单元411对应的读出电路412也可位于第一子区域1101和/或第二子区域1102中，并与第一光电传感单元411和/或第二光电传感单元413设置在不同层。
上述实施例描述的是同一区域中的第一光电传感单元和第二光电传感单元的平面布局方式。在竖直方向(芯片的不同层的堆叠方向)上，同一区域中的第一光电传感单元和第二光电传感单元可以位于信号处理芯片的同一层，也可以位于信号处理芯片的不同层。进一步地，在一些实施例中，第一光电传感单元和第二光电传感单元之间可以相互隔离，以防止同一区域中的第一光电传感单元和第二光电传感单元之间的相互影响。以第一光电传感单元为APD，第二光电传感单元为CIS为例，APD是高压器件，APD在工作时会对CIS产生干扰，通过将二者隔离可以有效降低二者之间的干扰，提高芯片的精度。
作为一个示例，同一区域中的第一光电传感单元和第二光电传感单元位于信号处理芯片的同一层，且该第一光电传感单元和该第二光电传感单元相互隔离。例如，可以在同一层中的第一光电传感单元和第二光电传感单元之间添加绝缘材料。
作为另一个示例，同一区域中的第一光电传感单元和第二光电传感单元可以位于信号处理芯片的不同层，且该第一光电传感单元和该第二光电传感单元之间设置有绝缘层。
如图7所示，可以将第二光电传感单元413设置在SOI结构的上层61，从而通过氧化层62将第一光电传感单元411和第二光电传感单元413相互隔离。当然，在一些实施例中，也可以将图7中的第一光电传感单元411和第二光电传感单元413的位置互换，同样可以起到将同一区域中的第一光电传感单元和第二光电传感单元相互隔离的效果。
进一步地，在一些实施例中，同一区域对应的第一光电传感单元和第二光电传感单元中的至少一个光电传感单元的光入射侧设置有透光的绝缘材料。
仍以图7为例，第一光电传感单元411的上方设置有SOG 64，SOG 64是一种透光的绝缘材料，既能够保证下层的第一光电传感单元411接收到入射光线，又能保证第一光电传感单元411和第二光电传感单元413之间相互隔离。
本发明实施例还提供了一种图像处理系统。如图12所示，该图像处理系统1200可包括信号处理芯片1210和数据处理器1220。信号处理芯片1210可以是前文任一实施例描述的信号处理芯片。数据处理器1220可被配置成 对信号处理芯片1210输出的数据进行处理，得到包含待测物体的深度图像(或具有深度信息的点云数据)。例如，数据处理器1220可从光信号的发射端获取用于指示该光信号的发射时间的时间数据，并从图像处理芯片1210中的第一CMOS读出电路接收用于指示光信号的飞行时间的时间数据；然后，数据处理器1220可以根据光信号的飞行时间，采用TOF原理，生成待测物体的深度图像。进一步地，当信号处理芯片1210包含第二光电传感阵列和第二CMOS读出电路时，数据处理器1220还可以根据第二CMOS读出电路输出的黑白或彩色的图像数据生成待测物体的黑白或彩色图像。
本发明实施例还提供了一种距离测量系统。如图13所示，该距离测量系统1300可包括发射器1310以及如图12所示的图像处理系统1200。发射器1310可被配置成发射光信号，如发射覆盖距离测量系统1300的FOV的光信号。图像处理系统1300可被配置成接收光信号遇到待测物体后反射回来的部分信号。可选地，在一些实施例中，距离测量系统1300可以为激光探测与测量系统，或称激光雷达。
该距离测量系统用于感测外部环境信息，例如，环境目标的距离信息、角度信息、反射强度信息、速度信息等。具体地，本发明实施方式的激光测量系统可应用于移动平台，所述激光测量系统可安装在移动平台的平台本体。具有激光测量系统的移动平台可对外部环境进行测量，例如，测量移动平台与障碍物的距离用于避障等用途，和对外部环境进行二维或三维的测绘。在某些实施方式中，移动平台包括无人飞行器、汽车和遥控车中的至少一种。当激光测量系统应用于无人飞行器时，平台本体为无人飞行器的机身。当激光测量系统应用于汽车时，平台本体为汽车的车身。当激光测量系统应用于遥控车时，平台本体为遥控车的车身。
在上述实施例中，可以全部或部分地通过软件、硬件、固件或者其他任意组合来实现。当使用软件实现时，可以全部或部分地以计算机程序产品的形式实现。所述计算机程序产品包括一个或多个计算机指令。在计算机上加载和执行所述计算机程序指令时，全部或部分地产生按照本发明实施例所述的流程或功能。所述计算机可以是通用计算机、专用计算机、计算机网络、或者其他可编程装置。所述计算机指令可以存储在计算机可读存储介质中，或者从一个计算机可读存储介质向另一个计算机可读存储介质传输，例如， 所述计算机指令可以从一个网站站点、计算机、服务器或数据中心通过有线(例如同轴电缆、光纤、数字用户线(digital subscriber line，DSL))或无线(例如红外、无线、微波等)方式向另一个网站站点、计算机、服务器或数据中心进行传输。所述计算机可读存储介质可以是计算机能够存取的任何可用介质或者是包含一个或多个可用介质集成的服务器、数据中心等数据存储设备。所述可用介质可以是磁性介质(例如，软盘、硬盘、磁带)、光介质(例如数字视频光盘(digital video disc，DVD))、或者半导体介质(例如固态硬盘(solid state disk，SSD))等。
本领域普通技术人员可以意识到，结合本文中所公开的实施例描述的各示例的单元及算法步骤，能够以电子硬件、或者计算机软件和电子硬件的结合来实现。这些功能究竟以硬件还是软件方式来执行，取决于技术方案的特定应用和设计约束条件。专业技术人员可以对每个特定的应用来使用不同方法来实现所描述的功能，但是这种实现不应认为超出本申请的范围。
在本申请所提供的几个实施例中，应该理解到，所揭露的系统、装置和方法，可以通过其它的方式实现。例如，以上所描述的装置实施例仅仅是示意性的，例如，所述单元的划分，仅仅为一种逻辑功能划分，实际实现时可以有另外的划分方式，例如多个单元或组件可以结合或者可以集成到另一个系统，或一些特征可以忽略，或不执行。另一点，所显示或讨论的相互之间的耦合或直接耦合或通信连接可以是通过一些接口，装置或单元的间接耦合或通信连接，可以是电性，机械或其它的形式。
所述作为分离部件说明的单元可以是或者也可以不是物理上分开的，作为单元显示的部件可以是或者也可以不是物理单元，即可以位于一个地方，或者也可以分布到多个网络单元上。可以根据实际的需要选择其中的部分或者全部单元来实现本实施例方案的目的。
另外，在本申请各个实施例中的各功能单元可以集成在一个处理单元中，也可以是各个单元单独物理存在，也可以两个或两个以上单元集成在一个单元中。
以上所述，仅为本申请的具体实施方式，但本申请的保护范围并不局限于此，任何熟悉本技术领域的技术人员在本申请揭露的技术范围内，可轻易想到变化或替换，都应涵盖在本申请的保护范围之内。因此，本申请的保护范围应以所述权利要求的保护范围为准。

Claims (20)

  1. 一种信号处理芯片，其特征在于，包括：
    第一光电传感阵列，被配置成接收光信号，并将所述光信号转换成第一电信号；
    第一互补金属氧化物半导体CMOS读出电路，所述第一CMOS读出电路被配置成接收所述第一电信号，对所述第一电信号进行处理，以获取用于指示所述光信号的飞行时间的时间数据；
    其中所述第一光电传感阵列为硅基的光电传感阵列，且所述第一光电传感阵列与所述第一CMOS读出电路集成在同一硅晶圆上。
  2. 如权利要求1所述的信号处理芯片，其特征在于，所述信号处理芯片还包括：
    第二光电传感阵列，所述第二光电传感阵列被配置成接收包含所述光信号和环境光的混合信号，将所述混合信号转换成第二电信号；
    第二CMOS读出电路，所述第二CMOS读出电路被配置成接收所述第二电信号，对所述第二电信号进行处理，得到彩色的或黑白的像素数据。
  3. 如权利要求2所述的信号处理芯片，其特征在于，所述信号处理芯片包含M×N块区域，所述第一光电传感阵列包含分别位于所述M×N块区域中的M×N个第一光电传感单元，所述第二光电传感阵列包含分别位于所述M×N块区域中的M×N个第二光电传感单元，其中M、N均为不小于1的正整数，且M×N大于1。
  4. 如权利要求3所述的信号处理芯片，其特征在于，所述M×N块区域中的每块区域包含互不重叠的第一子区域和第二子区域，所述每块区域对应的第一光电传感单元位于所述每块区域的第一子区域中，所述每块区域对应的第二光电传感单元位于所述每块区域的第二子区域中。
  5. 如权利要求3所述的信号处理芯片，其特征在于，所述M×N块区域中的T块区域中的每块区域对应的第一光电传感单元和第二光电传感单元相互隔离，其中T为不小于1的整数。
  6. 如权利要求5所述的信号处理芯片，其特征在于，所述T块区域中的每块区域对应的第一光电传感单元和第二光电传感分别位于所述信号处理芯片的不同层，且所述每块区域对应的第一光电传感单元和第二光电传感单元之间设置有绝缘层。
  7. 如权利要求6所述的信号处理芯片，其特征在于，所述每块区域对应的第一光电传感单元和第二光电传感单元中的至少一个光电传感单元的光入射侧设置有透光的绝缘材料。
  8. 如权利要求1-7中任一项所述的信号处理芯片，其特征在于，所述信号处理芯片还包含光滤波器，所述光滤波器设置在所述第一光电传感阵列的光入射侧，所述光滤波器被配置成对入射至所述第一光电传感阵列的光信号进行滤波，以得到目标波长的光信号。
  9. 如权利要求8所述的信号处理芯片，其特征在于，所述信号处理芯片还包含增透膜，所述增透膜设置在所述光滤波器的光入射侧。
  10. 如权利要求1-7中任一项所述的信号处理芯片，其特征在于，所述信号处理芯片还包括透镜，所述透镜设置在所述第一光电传感阵列中的L个第一光电传感单元的光入射侧，所述透镜用于对入射至所述L个第一光电传感单元的光信号的光线进行汇聚，其中L为不小于1的正整数。
  11. 如权利要求1-7中任一项所述的信号处理芯片，其特征在于，所述第一光电传感阵列与所述第一CMOS读出电路位于所述信号处理芯片的不同层中，且所述第一光电传感阵列与所述第一CMOS读出电路之间设置有绝缘层。
  12. 如权利要求1-7中任一项所述的信号处理芯片，其特征在于，所述信号处理芯片包含M×N块区域，所述第一光电传感阵列包含分别位于所述M×N块区域中的M×N个第一光电传感单元，所述第一CMOS读出电路包含与所述M×N个第一光电传感单元一一对应的M×N个读出电路，且所述M×N个读出电路中的每个读出电路与对应的第一光电传感单元位于所述M×N块区域的同一块区域中，其中M、N均为不小于1的正整数，且M×N大于1。
  13. 如权利要求12所述的信号处理芯片，其特征在于，所述M×N块区域中的每块区域对应的第一光电传感单元和读出电路在所述每块区域中并排设置或堆叠设置。
  14. 如权利要求1-7中任一项所述的信号处理芯片，其特征在于，所述第一光电传感阵列包含N列第一光电传感单元，所述第一CMOS读出电路包含与所述N列第一光电传感单元一一对应的N个时间数字转换器TDC，所述N个TDC被配置成分别处理所述N列第一光电传感单元接收到的光信 号，其中N为不小于1的正整数。
  15. 如权利要求1-7中任一项所述的信号处理芯片，其特征在于，所述第一光电传感阵列中的第一光电传感单元包括以下中的至少一种：雪崩光电二极管APD和硅光电倍增管SiPM。
  16. 如权利要求1-7中任一项所述的信号处理芯片，其特征在于，所述光信号的波长包括895nm至915nm之间的任一波长。
  17. 如权利要求1-7中任一项所述的信号处理芯片，其特征在于，所述光信号为激光信号或发光二极管LED生成的光信号。
  18. 一种图像处理系统，其特征在于，包括：
    如权利要求1-17中任一项所述的信号处理芯片；
    数据处理器，被配置成对所述信号处理芯片输出的数据进行处理，得到包含待测物体的距离信息的图像数据。
  19. 一种距离测量系统，其特征在于，包括：
    发射器，被配置成发射覆盖所述距离测量系统的视场角FOV的光信号；
    如权利要求18所述的图像处理系统，被配置成接收所述光信号遇到所述待测物体后反射回来的部分信号。
  20. 如权利要求19所述的距离测量系统，其特征在于，所述距离测量系统为激光雷达。
PCT/CN2017/099998 2017-08-31 2017-08-31 信号处理芯片、图像处理系统和距离测量系统 WO2019041257A1 (zh)

Priority Applications (2)

Application Number Priority Date Filing Date Title
CN201780004561.0A CN108513619A (zh) 2017-08-31 2017-08-31 信号处理芯片、图像处理系统和距离测量系统
PCT/CN2017/099998 WO2019041257A1 (zh) 2017-08-31 2017-08-31 信号处理芯片、图像处理系统和距离测量系统

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/CN2017/099998 WO2019041257A1 (zh) 2017-08-31 2017-08-31 信号处理芯片、图像处理系统和距离测量系统

Publications (1)

Publication Number Publication Date
WO2019041257A1 true WO2019041257A1 (zh) 2019-03-07

Family

ID=63375203

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2017/099998 WO2019041257A1 (zh) 2017-08-31 2017-08-31 信号处理芯片、图像处理系统和距离测量系统

Country Status (2)

Country Link
CN (1) CN108513619A (zh)
WO (1) WO2019041257A1 (zh)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109581399A (zh) * 2018-12-29 2019-04-05 西南技术物理研究所 一种大动态范围厘米级精度激光测距方法
CN109991582B (zh) * 2019-03-13 2023-11-03 上海交通大学 硅基混合集成激光雷达芯片系统
CN110007289B (zh) * 2019-03-21 2021-09-21 杭州蓝芯科技有限公司 一种基于飞行时间深度相机的运动伪差减小方法
CN117043947A (zh) * 2021-05-31 2023-11-10 华为技术有限公司 一种感应器芯片及终端设备

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103839951A (zh) * 2012-11-21 2014-06-04 台湾积体电路制造股份有限公司 双面照明图像传感器芯片及其形成方法
CN104505394A (zh) * 2014-12-10 2015-04-08 中国科学院半导体研究所 兼容测距的cmos图像传感器像素单元及其制作方法
CN107024696A (zh) * 2017-05-23 2017-08-08 河南华泰规划勘测设计咨询有限公司 一种激光测量系统

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102150037B (zh) * 2008-07-11 2014-06-04 康奈尔大学 集成电荷传感器的纳米流体通道及基于该纳米流体通道的方法
EP2513597B1 (en) * 2009-12-14 2020-06-24 Shilat Optronics Ltd Laser daylight designation and pointing
CN102438111A (zh) * 2011-09-20 2012-05-02 天津大学 一种基于双阵列图像传感器的三维测量芯片及系统
US8798229B2 (en) * 2011-09-30 2014-08-05 General Electric Company Detector modules and methods of manufacturing
CN104160295B (zh) * 2012-03-09 2017-09-15 株式会社半导体能源研究所 半导体装置的驱动方法

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103839951A (zh) * 2012-11-21 2014-06-04 台湾积体电路制造股份有限公司 双面照明图像传感器芯片及其形成方法
CN104505394A (zh) * 2014-12-10 2015-04-08 中国科学院半导体研究所 兼容测距的cmos图像传感器像素单元及其制作方法
CN107024696A (zh) * 2017-05-23 2017-08-08 河南华泰规划勘测设计咨询有限公司 一种激光测量系统

Also Published As

Publication number Publication date
CN108513619A (zh) 2018-09-07

Similar Documents

Publication Publication Date Title
US11598857B2 (en) Integrated lidar image-sensor devices and systems and related methods of operation
US11300665B2 (en) Rotating compact light ranging system
JP7292269B2 (ja) 拡張ダイナミックレンジを有するデジタルピクセル
JP7429274B2 (ja) 輝度を増強した光学撮像送信器
US20200191925A1 (en) Systems and methods for an apd array solid-state laser radar
US20170180698A1 (en) Depth sensor, image capture method, and image processing system using depth sensor
KR20200085909A (ko) 다중-광다이오드 픽셀 셀
KR20200024914A (ko) 전자적으로 스캔되는 방출기 어레이 및 동기화된 센서 어레이를 갖는 광 레인징 장치
WO2019041257A1 (zh) 信号处理芯片、图像处理系统和距离测量系统
WO2019113368A1 (en) Rotating compact light ranging system
EP3602110A1 (en) Time of flight sensor
US10404925B2 (en) Chip scale multispectral imaging and ranging
WO2022198386A1 (zh) 激光测距装置、激光测距方法和可移动平台
WO2023164944A1 (zh) 雪崩光电二极管阵列芯片、接收器、测距装置及可移动平台
WO2022170476A1 (zh) 激光接收电路及其控制方法、测距装置、移动平台
Hardy et al. Intra-pixel response of infrared detector arrays for JWST
WO2019041250A1 (zh) 电子器件及包括其的测距装置和电子设备
US20230408699A1 (en) Time-of-flight image sensor with quantom dot photodetectors
US20210306580A1 (en) Image sensing device

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 17923305

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 17923305

Country of ref document: EP

Kind code of ref document: A1