WO2021068156A1 - Optical sensor, ranging system based on time of flight, and electronic apparatus - Google Patents

Optical sensor, ranging system based on time of flight, and electronic apparatus Download PDF

Info

Publication number
WO2021068156A1
WO2021068156A1 PCT/CN2019/110336 CN2019110336W WO2021068156A1 WO 2021068156 A1 WO2021068156 A1 WO 2021068156A1 CN 2019110336 W CN2019110336 W CN 2019110336W WO 2021068156 A1 WO2021068156 A1 WO 2021068156A1
Authority
WO
WIPO (PCT)
Prior art keywords
capacitor
charge output
sensing voltage
sampling
voltage
Prior art date
Application number
PCT/CN2019/110336
Other languages
French (fr)
Chinese (zh)
Inventor
杨孟达
Original Assignee
深圳市汇顶科技股份有限公司
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 深圳市汇顶科技股份有限公司 filed Critical 深圳市汇顶科技股份有限公司
Priority to CN201980004445.8A priority Critical patent/CN111108411B/en
Priority to PCT/CN2019/110336 priority patent/WO2021068156A1/en
Publication of WO2021068156A1 publication Critical patent/WO2021068156A1/en

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
    • 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
    • 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
    • G01S17/88—Lidar systems specially adapted for specific applications
    • G01S17/89—Lidar systems specially adapted for specific applications for mapping or imaging
    • 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
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N23/00—Cameras or camera modules comprising electronic image sensors; Control thereof
    • H04N23/70—Circuitry for compensating brightness variation in the scene
    • H04N23/73—Circuitry for compensating brightness variation in the scene by influencing the exposure time

Definitions

  • This application relates to a light sensor, and in particular to a light sensor that can perform the next exposure operation while reading out, and its related time-of-flight-based ranging system and electronic device.
  • One of the objectives of the present application is to disclose a light sensor and its related time-of-flight-based ranging system and electronic device to solve the above-mentioned problems.
  • An embodiment of the present application discloses a light sensor for sensing a reflection signal generated by a light pulse signal sent by a light pulse generating unit being reflected by a target.
  • the light sensor includes: a pixel array including a plurality of pixels , Each pixel of the plurality of pixels includes: a photodiode, which is used to sense the reflected signal to generate a charge during an exposure operation; and a charge output circuit, which is used to selectively couple according to the first charge output signal Connected to the photodiode to generate a first sensing voltage; a second charge output circuit for selectively coupling to the photodiode according to a second charge output signal to generate a second sensing voltage, wherein The second charge output signal and the first charge output signal have different phases; and the sampling circuit includes: a first capacitor, the first end of the first capacitor is coupled to the first charge output circuit and the In the second charge output circuit, the second terminal of the first capacitor is coupled to the first voltage; the sampling switch is selectively turned on according to the
  • Another embodiment of the present application discloses a time-of-flight-based ranging system, including the optical sensor and the optical pulse generating unit.
  • Another embodiment of the present application discloses an electronic device including the optical sensor.
  • Another embodiment of the present application discloses an electronic device, including the aforementioned time-of-flight-based ranging system.
  • the optical sensor and the related time-of-flight-based ranging system and electronic device of the present application can perform the next exposure operation while reading out, so the frame rate can be increased to solve the above-mentioned problems.
  • Fig. 1 is a schematic functional block diagram of an embodiment of the time-of-flight-based ranging system of the present application.
  • FIG. 2 is a schematic diagram of an embodiment of one of the pixels in the pixel array.
  • FIG. 3 is a flowchart of an embodiment of the operation of the pixels of the photosensor of the application.
  • FIG. 4 is a schematic diagram of an embodiment of an electronic device of this application.
  • optical sensor and its related time-of-flight-based distance measurement system and electronic device disclosed in the present application can use a sampling circuit to perform readout operation while simultaneously performing the next exposure operation.
  • a further description is as follows.
  • Fig. 1 is a schematic functional block diagram of an embodiment of the time-of-flight-based ranging system of the present application.
  • the distance measurement system 100 based on time-of-flight can be used to detect the distance between the target 101 and the distance measurement system 100. It should be noted that the distance between the target 101 and the distance measurement system 100 should be less than or equal to that of the distance measurement system 100. Maximum measuring distance.
  • the distance measuring system 100 may be a three-dimensional imaging system, which may use a time-of-flight method to measure the distance of surrounding objects, thereby obtaining depth of field and three-dimensional image information.
  • the ranging system 100 may be implemented as an optical ranging system based on time of flight.
  • the distance measuring system 100 may include (but is not limited to) a light pulse generating unit 102 and a light sensor 103.
  • the light pulse generating unit 102 may be implemented by a light emitting unit to generate the light pulse signal EL.
  • the light pulse signal EL may include a plurality of light pulses.
  • the light pulse generating unit 102 may be (but not limited to) a laser diode (LD), a light emitting diode (LED), or other light emitting units that can generate light pulses.
  • the light pulse signal EL generated by the light pulse generating unit 102 may include light pulses of different phases. In this embodiment, the light pulse signal EL generated by the light pulse generating unit 102 sequentially includes N light pulses having the first phase.
  • the light pulse, N light pulses with the second phase, N light pulses with the third phase, and N light pulses with the fourth phase are repeatedly circulated, where N is an integer greater than 0.
  • the first phase is 0 degrees
  • the second phase is 90 degrees
  • the second phase is 180 degrees
  • the third phase is 270 degrees.
  • the optical sensor 103 is used to sample the reflected signal RL generated by the reflected light pulse signal EL of the target 101 to detect the distance between the ranging system 100 (or the time-of-flight optical sensor 130) and the target 101. Specifically, the optical sensor 103 performs exposure operation, sampling operation, and reading operation for every N light pulse signals EL having the first phase, the second phase, the third phase, and the fourth phase. The details of the operation will be explained as follows.
  • the light sensor 103 includes (but is not limited to) a pixel array 104 and a reading circuit 105.
  • the pixel array 104 includes a plurality of pixels (not shown in FIG. 1), and the reading circuit 105 is coupled to the pixel array 104.
  • the reading circuit 105 may include an amplifier 106, an analog-to-digital converter 108, and an arithmetic circuit 110.
  • FIG. 2 is a schematic diagram of an embodiment of one of the pixels located in the i-th row in the pixel array 104. As shown in FIG. 2, the photodiode PD of the pixel 204 is used to sense the reflected signal RL to generate electric charges during the exposure operation.
  • the first charge output circuit 2041 of the pixel 204 is used to control the switch MT1 according to the first charge output signal TX1 to selectively couple the first charge output circuit 2041 to the photodiode PD.
  • TX1 controls the switch
  • MT1 When MT1 is turned on, the charge of the photodiode PD flows into the floating diffusion region FDN1 of the first charge output circuit 2041, and is driven by the source follower transistor MF1 to generate the first sensing voltage at the source output SFO1 of the source follower transistor MF1 .
  • the switch MT1 is coupled between the gate of the source follower transistor MF1 and the photodiode PD.
  • the first charge output circuit 2041 further includes a reset transistor MR1 and a selection transistor MS1.
  • the source of the reset transistor MR1 is coupled to the gate of the source follower transistor MF1.
  • the reset transistor MR1 is selectively reset according to the reset signal R1.
  • the floating diffusion FDN1 and the source output SFO1 of the first charge output circuit 2041 are used to reset the first sensing voltage.
  • the drains of the reset transistor MR1 and the source follower transistor MF1 are both coupled to the second voltage V2,
  • the drain of the selection transistor MS1 is coupled to the drain of the source follower transistor MF1, the drain of the selection transistor MS1 is coupled to the sampling circuit 2043, and the selection transistor MS1 selectively outputs the source SFO1 according to the first selection control signal FD1 , That is, the first sensing voltage is transmitted to the sampling circuit 2043.
  • the second charge output circuit 2042 of the pixel 204 is used to control the switch MT2 according to the second charge output signal TX2 to selectively couple the second charge output circuit 2042 to the photodiode PD.
  • TX2 controls the switch
  • the charge of the photodiode PD flows into the floating diffusion area FDN2 of the second charge output circuit 2042, and is driven by the source follower transistor MF2 to generate the second sensing voltage at the source output SFO2 of the source follower transistor MF2 .
  • the switch MT2 is coupled between the gate of the source follower transistor MF2 and the photodiode PD.
  • the second charge output circuit 2042 further includes a reset transistor MR2 and a selection transistor MS2.
  • the source of the reset transistor MR2 is coupled to the gate of the source follower transistor MF2.
  • the reset transistor MR2 is selectively reset according to the reset signal R2.
  • the floating diffusion FDN2 and the source output SFO2 of the second charge output circuit 2042 are used to reset the second sensing voltage.
  • the drains of the reset transistor MR2 and the source follower transistor MF2 are both coupled to the second voltage V2.
  • the drain of the selection transistor MS2 is coupled to the drain of the source follower transistor MF2, the drain of the selection transistor MS2 is coupled to the sampling circuit 2043, and the selection transistor MS2 selectively outputs the source SFO1 according to the second selection control signal FD2 , That is, the second sensing voltage is transmitted to the sampling circuit 2043.
  • the second charge output signal TX2 and the first charge output signal TX1 are turned on at different times.
  • the second charge output signal TX2 and the first charge output signal TX1 have different phases, such as the second charge output signal TX2 and The phase difference of the first charge output signal TX1 is 180 degrees.
  • the pixel 204 may further include a first reset transistor MP, but the application is not limited to this.
  • the first reset transistor MP is coupled between the photodiode PD and the second voltage V2.
  • the transistor MP is used to selectively reset the photodiode PD according to the reset signal TXB, so as to reduce the chance of accumulating the charges generated by the non-reflective signal RL.
  • the sampling circuit 2043 of the pixel 204 includes a bias transistor MV, a first capacitor C1, a second capacitor C2, a sampling switch MH, a source follower transistor MF, and a row selection transistor MS.
  • the sampling circuit 2043 is used to store the first sensing voltage and the second sensing voltage in the second capacitor C2 and the first capacitor C1 during the sampling operation.
  • the drain of the bias transistor MV is coupled to the source of the selection transistor MS1 and the source of the selection transistor MS2, and the first end of the first capacitor C1.
  • the source of the bias transistor MV is coupled to the first voltage V1, and the bias transistor MV is selectively turned on according to the bias signal VB to provide current to the sampling circuit 2043.
  • the second terminal of the first capacitor C1 is coupled to the first voltage and the source of the sampling switch MH, the drain of the sampling switch MH is coupled to the first terminal of the second capacitor C2, and the second terminal of the second capacitor C2 is coupled To the first voltage V1.
  • the sampling switch MH is selectively turned on according to the sampling control signal SH, so that the first terminal of the second capacitor C2 is selectively coupled to one of the drains of the selection transistor MS1 or the selection transistor MS2.
  • the sampling circuit 2043 further includes a source follower transistor MF and a row selection transistor MS.
  • the gate of the source follower transistor MF is coupled to the first terminal of the second capacitor C2, and the drain of the source follower transistor MF is coupled to the second voltage V2.
  • the drain of the source follower transistor MF is coupled to the drain of the row selection transistor MS, and the row selection transistor MS is selectively turned on according to the row selection signal S.
  • the transistors are all N-type transistors, and the second voltage V2 is greater than the first voltage V1. That is, in the embodiment of FIG. 2, all the transistors in the pixel 204 have the same polarity.
  • the transistors in the pixel 204 can also be P-type transistors, and the magnitude relationship between the first voltage V1 and the second voltage V2 can be adjusted accordingly.
  • the transistors in the pixel 204 may have both N-type transistors and P-type transistors.
  • FIG. 3 is a flowchart of an embodiment of the operation of the pixel 204 of the light sensor 103 of the present application.
  • the reset signal R1 and the reset signal R2 cause the source of the first charge output circuit 2041 to output SFO1 (that is, the first sensing voltage) and the second The source output SFO2 (ie, the second sensing voltage) of the charge output circuit 2042 is reset.
  • the light pulse signal EL of the light pulse generating unit 110 will include N Light pulses, and the first charge output signal TX1 and the second charge output signal TX2 respectively correspond to each of the N light pulses to turn on the switch MT1 and the switch MT2, so as to cause the reflected signal RL to the photodiode PD
  • the charge is introduced into the first charge output circuit 2041 and the second charge output circuit 2042, and accumulated into the first sensing voltage and the second sensing voltage, that is, N light pulses will correspond to N first The charge output signal TX1 and N second charge output signals TX1.
  • the switch MT2 is connected to the switch MT1 to be turned on, and the switch MT1 and the switch MT2 will not be turned on at the same time, or the switch MT1 and the switch MT2 are turned on The time is staggered.
  • the reset signal TXB resets the photodiode PD when the first charge output signal TX1 and the second charge output signal TX2 turn on the switch MT1 and the switch MT2 to reduce the accumulation of the non-reflected signal RL. The chance of charge.
  • the bias signal VB in the sampling circuit 2043 turns off the bias transistor MV, and the sampling circuit 2043 does not perform sampling. Then, in the sampling operation, the bias signal VB will turn on the bias transistor MV, and the first selection control signal FD1 will turn on the selection transistor MS1, and the sampling control signal SH_i (SH_i represents the sampling control signal SH of the i-th row).
  • the bias signal VB will first make the bias transistor MV non-conducting, and then the row selection signal S will turn on the row selection transistor MS, and the second capacitor C2 is read from the second capacitor C2.
  • a sensed voltage is sent to the reading circuit 105.
  • the sampling control signal SH_i will be turned on. Since the first selection control signal FD1 and the second selection control signal FD2 do not turn on the selection transistor MS1 and the selection transistor MS2, the voltages of the first capacitor C1 and the second capacitor C2 will be different from each other. The balance is reached to the average value of the first sensing voltage and the second sensing voltage, and is read to the reading circuit 105.
  • FIG. 3 shows the sampling control of the i+1th line.
  • the signal SH_i+1 and the sampling control signal SH_i+2 of the i+2th row are only exemplary representations, so the sampling control signals of the remaining rows are not shown in FIG. 3 one by one.
  • each column of pixels shares a reading circuit 105, the operation of controlling the output of the first capacitor C1 and the second capacitor C2 by the sampling control signal of each row cannot be performed at the same time, that is, the sampling control signal SH_i of the i-th row and the first capacitor C2
  • the sampling control signal SH_i+1 of row i+1, the sampling control signal SH_i+2 of row i+2, and the sampling control signal of other rows should be staggered, and the sampling control signal of each row makes the sampling switch MH finish conducting time
  • the point and the time point at which the sampling control signal of the next row makes the sampling switch MH start to be turned on must be at least sufficiently long for the first sensing voltage to be output.
  • the sampling circuit 2043 temporarily stores the first sensing voltage and the second sensing voltage, so the readout operation will not be affected by the next exposure operation, so the readout operation It can be performed simultaneously with the next exposure operation, in other words, the exposure operation can also be performed simultaneously with the previous readout operation. Compared with the operation of the conventional light sensor, additional time for the readout operation can be saved.
  • the reading circuit 105 successively reads the first sensing voltage and the average value of the first sensing voltage and the second sensing voltage from the second capacitor C2, and then generates a read result in response to the first sensing voltage.
  • a sensed voltage and the difference between the average value of the first sensed voltage and the second sensed voltage that is, the first sensed voltage-(the first sensed voltage + the first sensed voltage) Two sensing voltage)/2, that is, (the first sensing voltage-the second sensing voltage)/2.
  • the reading circuit 105 includes an amplifier 106, an analog-to-digital converter 108, and an arithmetic unit 110.
  • the amplifier 106 can be used to enhance the readout of the first sensing voltage and the average value of the first sensing voltage and the second sensing voltage
  • the analog-to-digital converter 108 can be used to control the amplifier 106
  • the enhanced first sensing voltage and the average value of the first sensing voltage and the second sensing voltage perform analog-to-digital conversion
  • the arithmetic unit 110 is used to perform analog-to-digital conversion on the enhanced analog-to-digital conversion
  • the first sensing voltage and the average value of the first sensing voltage and the second sensing voltage are subjected to analog-to-digital conversion for difference calculation.
  • FIG. 4 is a schematic diagram of an embodiment of an electronic device of this application.
  • the electronic device 400 is used for ranging, and the electronic device 400 includes a time-of-flight based ranging system 100, in some embodiments.
  • the electronic device 400 may be any electronic device such as a smart phone, a personal digital assistant, a handheld computer system, or a tablet computer.

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)
  • Multimedia (AREA)
  • Signal Processing (AREA)
  • Transforming Light Signals Into Electric Signals (AREA)

Abstract

An optical sensor, a ranging system (100) based on time of flight, and an electronic apparatus (400). The sensor is used for sensing a reflection signal (RL) produced by a target object (101) reflecting an optical pulse signal (EL) sent by an optical pulse producing unit (102), the sensor comprising a pixel array (104) comprising a plurality of pixels, each pixel (204) amongst the plurality of pixels comprising: a photodiode (PD), a first charge output circuit (2041), a second charge output circuit (2042), and a sampling circuit (2043), and the sampling circuit (2043) comprising: a first capacitor (C1), a sampling switch (MH), and a second capacitor (C2).

Description

光传感器、基于飞行时间的测距***和电子装置Light sensor, time-of-flight-based ranging system and electronic device 技术领域Technical field
本申请涉及光传感器，尤其涉及一种能够在读出操作的同时进行下一次的曝光操作的光传感器，及其相关的基于飞行时间的测距***和电子装置。This application relates to a light sensor, and in particular to a light sensor that can perform the next exposure operation while reading out, and its related time-of-flight-based ranging system and electronic device.
背景技术Background technique
基于飞行时间(time of flight，TOF)的距离测量技术中，由于光传感器的像素内部没有储存元件，导致每次曝光操作都需要等待前一次的读出操作结束后才能进行，使得帧率无法提升。因此，需要一种创新的光传感器设计来解决此问题。In the distance measurement technology based on time of flight (TOF), because there are no storage elements inside the pixels of the light sensor, each exposure operation needs to wait for the previous readout operation to be completed, so that the frame rate cannot be increased. . Therefore, an innovative light sensor design is needed to solve this problem.
发明内容Summary of the invention
本申请的目的之一在于公开一种光传感器及其相关的基于飞行时间的测距***和电子装置，来解决上述问题。One of the objectives of the present application is to disclose a light sensor and its related time-of-flight-based ranging system and electronic device to solve the above-mentioned problems.
本申请的一实施例公开了一种光传感器，用以感测光脉冲产生单元所发送的光脉冲信号被目标物反射所产生的反射信号，所述光传感器包括：像素阵列，包括多个像素，所述多个像素中的每一像素包括：光电二极管，用来在曝光操作时，传感所述反射信号以产生电荷；一电荷输出电路，用以根据第一电荷输出信号选择性地耦接于所述光电二极管，以产生第一感测电压；第二电荷输出电路，用以根据第二电荷输出信号选择性地耦接于所述光电二极管，以产生第二感测电压，其中所述第二电荷输出信号和所述第一电荷输出信号具有不同的相位；以及采样电路，包括：第一电容，所述第一 电容的第一端耦接于所述第一电荷输出电路和所述第二电荷输出电路，所述第一电容的第二端耦接于第一电压；采样开关，依据采样控制信号选择性地导通；以及第二电容，所述第二电容的第一端通过所述采样开关选择性地耦接于所述第一电荷输出电路、所述第二电荷输出电路和所述第一电容的所述第一端，所述第二电容的第二端耦接于所述第一电压。An embodiment of the present application discloses a light sensor for sensing a reflection signal generated by a light pulse signal sent by a light pulse generating unit being reflected by a target. The light sensor includes: a pixel array including a plurality of pixels , Each pixel of the plurality of pixels includes: a photodiode, which is used to sense the reflected signal to generate a charge during an exposure operation; and a charge output circuit, which is used to selectively couple according to the first charge output signal Connected to the photodiode to generate a first sensing voltage; a second charge output circuit for selectively coupling to the photodiode according to a second charge output signal to generate a second sensing voltage, wherein The second charge output signal and the first charge output signal have different phases; and the sampling circuit includes: a first capacitor, the first end of the first capacitor is coupled to the first charge output circuit and the In the second charge output circuit, the second terminal of the first capacitor is coupled to the first voltage; the sampling switch is selectively turned on according to the sampling control signal; and the second capacitor, the first terminal of the second capacitor The sampling switch is selectively coupled to the first charge output circuit, the second charge output circuit, and the first end of the first capacitor, and the second end of the second capacitor is coupled to In the first voltage.
本申请的另一实施例公开了一种基于飞行时间的测距***，包括所述的光传感器以及所述光脉冲产生单元。Another embodiment of the present application discloses a time-of-flight-based ranging system, including the optical sensor and the optical pulse generating unit.
本申请的另一实施例公开了一种电子装置，包括所述的光传感器。Another embodiment of the present application discloses an electronic device including the optical sensor.
本申请的另一实施例公开了一种电子装置，包括所述的基于飞行时间的测距***。Another embodiment of the present application discloses an electronic device, including the aforementioned time-of-flight-based ranging system.
本申请的光传感器及其相关的基于飞行时间的测距***和电子装置能够在读出操作的同时进行下一次的曝光操作，因此能提升帧率以解决上述问题。The optical sensor and the related time-of-flight-based ranging system and electronic device of the present application can perform the next exposure operation while reading out, so the frame rate can be increased to solve the above-mentioned problems.
附图说明Description of the drawings
图1是本申请的基于飞行时间的测距***的实施例的功能方框示意图。Fig. 1 is a schematic functional block diagram of an embodiment of the time-of-flight-based ranging system of the present application.
图2为像素阵列中的其中一像素的实施例的示意图。FIG. 2 is a schematic diagram of an embodiment of one of the pixels in the pixel array.
图3为本申请的光传感器的像素的操作实施例的流程图。FIG. 3 is a flowchart of an embodiment of the operation of the pixels of the photosensor of the application.
图4为本申请电子装置的实施例的示意图。FIG. 4 is a schematic diagram of an embodiment of an electronic device of this application.
具体实施方式Detailed ways
在说明书及之前的权利要求书当中使用了某些词汇来指称特定的组件。本领域的技术人员应可理解，制造商可能会用不同的名词 来称呼同样的组件。本说明书及之前的权利要求书并不以名称的差异来作为区分组件的方式，而是以组件在功能上的差异来作为区分的基准。在通篇说明书及之前的权利要求书当中所提及的“包括”为一开放式的用语，故应解释成“包括但不限定于”。此外，“耦接”一词在此包括任何直接和间接的电连接手段。因此，若文中描述一第一装置耦接于一第二装置，则代表所述第一装置可直接电连接于所述第二装置，或通过其它装置或连接手段间接地电连接到所述第二装置。Certain words are used in the specification and the preceding claims to refer to specific components. Those skilled in the art should understand that manufacturers may use different terms to refer to the same components. This specification and the previous claims do not use differences in names as a way to distinguish components, but use differences in functions of components as a basis for distinction. The "including" mentioned in the entire specification and the preceding claims is an open term, so it should be interpreted as "including but not limited to". In addition, the term "coupled" herein includes any direct and indirect electrical connection means. Therefore, if it is described in the text that a first device is coupled to a second device, it means that the first device can be directly electrically connected to the second device, or indirectly electrically connected to the second device through other devices or connection means. Two devices.
本申请所公开的光传感器及其相关的基于飞行时间的测距***和电子装置，能够通过采样电路来使进行读出操作时，同时进行下一次的曝光操作，进一步的说明如下。The optical sensor and its related time-of-flight-based distance measurement system and electronic device disclosed in the present application can use a sampling circuit to perform readout operation while simultaneously performing the next exposure operation. A further description is as follows.
图1是本申请的基于飞行时间的测距***的实施例的功能方框示意图。基于飞行时间的测距***100可用于探测目标物101与测距***100之间的距离，需注意的是，目标物101与测距***100之间的距离应小于或等于测距***100的最大测量距离。举例来说(但本申请不限于此)，测距***100可以是三维成像***，其可采用时间飞行法来测量周遭目标物的距离，从而获得景深和三维图像信息。在此实施例中，测距***100可实施为基于飞行时间的光学测距***。Fig. 1 is a schematic functional block diagram of an embodiment of the time-of-flight-based ranging system of the present application. The distance measurement system 100 based on time-of-flight can be used to detect the distance between the target 101 and the distance measurement system 100. It should be noted that the distance between the target 101 and the distance measurement system 100 should be less than or equal to that of the distance measurement system 100. Maximum measuring distance. For example (but the application is not limited to this), the distance measuring system 100 may be a three-dimensional imaging system, which may use a time-of-flight method to measure the distance of surrounding objects, thereby obtaining depth of field and three-dimensional image information. In this embodiment, the ranging system 100 may be implemented as an optical ranging system based on time of flight.
测距***100可包括(但不限于)光脉冲产生单元102和光传感器103。光脉冲产生单元102可由发光单元来实施，以产生光脉冲信号EL。光脉冲信号EL可包括多个光脉冲。光脉冲产生单元102可以是(但不限于)激光二极管(laser diode，LD)、发光二极管(light emitting diode，LED)或其他可以产生光光脉冲的发光单元。具体来说，光脉冲产生单元102产生的光脉冲信号EL可包括不同相位的光脉冲，在本实施例中，光脉冲产生单元102产生的光脉冲信号EL依序包括N个具有第一相位的光脉冲、N个具有第二相位的光脉冲、N个具有第三相位的光脉冲以及N个具有第四相位的光脉冲，并重复地循环，其中N为大于0的整数。在一个实施例中，第一相 位为0度、第二相位为90度、第二相位为180度、第三相位为270度。The distance measuring system 100 may include (but is not limited to) a light pulse generating unit 102 and a light sensor 103. The light pulse generating unit 102 may be implemented by a light emitting unit to generate the light pulse signal EL. The light pulse signal EL may include a plurality of light pulses. The light pulse generating unit 102 may be (but not limited to) a laser diode (LD), a light emitting diode (LED), or other light emitting units that can generate light pulses. Specifically, the light pulse signal EL generated by the light pulse generating unit 102 may include light pulses of different phases. In this embodiment, the light pulse signal EL generated by the light pulse generating unit 102 sequentially includes N light pulses having the first phase. The light pulse, N light pulses with the second phase, N light pulses with the third phase, and N light pulses with the fourth phase are repeatedly circulated, where N is an integer greater than 0. In one embodiment, the first phase is 0 degrees, the second phase is 90 degrees, the second phase is 180 degrees, and the third phase is 270 degrees.
光传感器103用以对目标物101反射光脉冲信号EL所产生的反射信号RL进行采样，以侦测测距***100(或飞行时间光传感器130)与目标物101之间的距离。具体来说，光传感器103会针对每N个具有所述第一相位、所述第二相位、所述第三相位和所述第四相位的光脉冲信号EL均进行曝光操作、采样操作与读出操作，其细节将说明如下。The optical sensor 103 is used to sample the reflected signal RL generated by the reflected light pulse signal EL of the target 101 to detect the distance between the ranging system 100 (or the time-of-flight optical sensor 130) and the target 101. Specifically, the optical sensor 103 performs exposure operation, sampling operation, and reading operation for every N light pulse signals EL having the first phase, the second phase, the third phase, and the fourth phase. The details of the operation will be explained as follows.
光传感器103包括(但不限于)像素阵列104和读取电路105。像素阵列104包括多个像素(未绘示于图1)，读取电路105耦接至像素阵列104，在本实施例中，读取电路105可以包括放大器106、模数转换器108和运算电路110。图2为像素阵列104中位于第i行的其中一像素的实施例的示意图。如图2所示，像素204的光电二极管PD用来在所述曝光操作时，传感反射信号RL以产生电荷。The light sensor 103 includes (but is not limited to) a pixel array 104 and a reading circuit 105. The pixel array 104 includes a plurality of pixels (not shown in FIG. 1), and the reading circuit 105 is coupled to the pixel array 104. In this embodiment, the reading circuit 105 may include an amplifier 106, an analog-to-digital converter 108, and an arithmetic circuit 110. FIG. 2 is a schematic diagram of an embodiment of one of the pixels located in the i-th row in the pixel array 104. As shown in FIG. 2, the photodiode PD of the pixel 204 is used to sense the reflected signal RL to generate electric charges during the exposure operation.
像素204的第一电荷输出电路2041用以根据第一电荷输出信号TX1来控制开关MT1，以选择性地使第一电荷输出电路2041耦接于光电二极管PD，当第一电荷输出信号TX1控制开关MT1导通时，光电二极管PD的电荷会流入第一电荷输出电路2041的浮置扩散区FDN1，并通过源跟随晶体管MF1的驱动以在源跟随晶体管MF1的源极输出SFO1产生第一感测电压。开关MT1耦接于源跟随晶体管MF1的栅极和光电二极管PD之间。第一电荷输出电路2041另包括重置晶体管MR1和选择晶体管MS1，重置晶体管MR1的源极耦接至源跟随晶体管MF1的栅极，重置晶体管MR1依据重置信号R1来选择性地重置第一电荷输出电路2041的浮置扩散区FDN1和源极输出SFO1，以重置所述第一感测电压，重置晶体管MR1和源跟随晶体管MF1的漏极均耦接至第二电压V2，选择晶体管MS1的漏极耦接至源跟随晶体管MF1的漏极，选择晶体管MS1的漏极则耦接至采样电路2043，选择晶体管MS1依据第一选择控制信号FD1来选择性地将源极输出SFO1，即所述第一感测电压，传送至采样电 路2043。The first charge output circuit 2041 of the pixel 204 is used to control the switch MT1 according to the first charge output signal TX1 to selectively couple the first charge output circuit 2041 to the photodiode PD. When the first charge output signal TX1 controls the switch When MT1 is turned on, the charge of the photodiode PD flows into the floating diffusion region FDN1 of the first charge output circuit 2041, and is driven by the source follower transistor MF1 to generate the first sensing voltage at the source output SFO1 of the source follower transistor MF1 . The switch MT1 is coupled between the gate of the source follower transistor MF1 and the photodiode PD. The first charge output circuit 2041 further includes a reset transistor MR1 and a selection transistor MS1. The source of the reset transistor MR1 is coupled to the gate of the source follower transistor MF1. The reset transistor MR1 is selectively reset according to the reset signal R1. The floating diffusion FDN1 and the source output SFO1 of the first charge output circuit 2041 are used to reset the first sensing voltage. The drains of the reset transistor MR1 and the source follower transistor MF1 are both coupled to the second voltage V2, The drain of the selection transistor MS1 is coupled to the drain of the source follower transistor MF1, the drain of the selection transistor MS1 is coupled to the sampling circuit 2043, and the selection transistor MS1 selectively outputs the source SFO1 according to the first selection control signal FD1 , That is, the first sensing voltage is transmitted to the sampling circuit 2043.
像素204的第二电荷输出电路2042用以根据第二电荷输出信号TX2来控制开关MT2，以选择性地使第二电荷输出电路2042耦接于光电二极管PD，当第二电荷输出信号TX2控制开关MT2导通时，光电二极管PD的电荷会流入第二电荷输出电路2042的浮置扩散区FDN2，并通过源跟随晶体管MF2的驱动以在源跟随晶体管MF2的源极输出SFO2产生第二感测电压。开关MT2耦接于源跟随晶体管MF2的栅极和光电二极管PD之间。第二电荷输出电路2042另包括重置晶体管MR2和选择晶体管MS2，重置晶体管MR2的源极耦接至源跟随晶体管MF2的栅极，重置晶体管MR2依据重置信号R2来选择性地重置第二电荷输出电路2042的浮置扩散区FDN2和源极输出SFO2，以重置所述第二感测电压，重置晶体管MR2和源跟随晶体管MF2的漏极均耦接至第二电压V2。选择晶体管MS2的漏极耦接至源跟随晶体管MF2的漏极，选择晶体管MS2的漏极则耦接至采样电路2043，选择晶体管MS2依据第二选择控制信号FD2来选择性地将源极输出SFO1，即所述第二感测电压，传送至采样电路2043。The second charge output circuit 2042 of the pixel 204 is used to control the switch MT2 according to the second charge output signal TX2 to selectively couple the second charge output circuit 2042 to the photodiode PD. When the second charge output signal TX2 controls the switch When MT2 is turned on, the charge of the photodiode PD flows into the floating diffusion area FDN2 of the second charge output circuit 2042, and is driven by the source follower transistor MF2 to generate the second sensing voltage at the source output SFO2 of the source follower transistor MF2 . The switch MT2 is coupled between the gate of the source follower transistor MF2 and the photodiode PD. The second charge output circuit 2042 further includes a reset transistor MR2 and a selection transistor MS2. The source of the reset transistor MR2 is coupled to the gate of the source follower transistor MF2. The reset transistor MR2 is selectively reset according to the reset signal R2. The floating diffusion FDN2 and the source output SFO2 of the second charge output circuit 2042 are used to reset the second sensing voltage. The drains of the reset transistor MR2 and the source follower transistor MF2 are both coupled to the second voltage V2. The drain of the selection transistor MS2 is coupled to the drain of the source follower transistor MF2, the drain of the selection transistor MS2 is coupled to the sampling circuit 2043, and the selection transistor MS2 selectively outputs the source SFO1 according to the second selection control signal FD2 , That is, the second sensing voltage is transmitted to the sampling circuit 2043.
其中第二电荷输出信号TX2和第一电荷输出信号TX1在不同时间导通，举例来说，第二电荷输出信号TX2和第一电荷输出信号TX1具有不同的相位，例如第二电荷输出信号TX2和第一电荷输出信号TX1的相位差为180度。The second charge output signal TX2 and the first charge output signal TX1 are turned on at different times. For example, the second charge output signal TX2 and the first charge output signal TX1 have different phases, such as the second charge output signal TX2 and The phase difference of the first charge output signal TX1 is 180 degrees.
在本实施例中，像素204可另包括第一重置晶体管MP，但本申请不以此限，第一重置晶体管MP耦接于光电二极管PD和第二电压V2之间，第一重置晶体管MP用来依据重置信号TXB选择性地重置光电二极管PD，以降低累积到非反射信号RL所产生的电荷的机会。In this embodiment, the pixel 204 may further include a first reset transistor MP, but the application is not limited to this. The first reset transistor MP is coupled between the photodiode PD and the second voltage V2. The transistor MP is used to selectively reset the photodiode PD according to the reset signal TXB, so as to reduce the chance of accumulating the charges generated by the non-reflective signal RL.
像素204的采样电路2043包括偏置晶体管MV、第一电容C1、第二电容C2、采样开关MH、源跟随晶体管MF、行选择晶体管MS。采样电路2043用来在采样操作时，储存所述第一感测电压和所述第 二感测电压于第二电容C2和第一电容C1。偏置晶体管MV的漏极耦接至选择晶体管MS1的源极和选择晶体管MS2的源极以及第一电容C1的第一端。偏置晶体管MV的源极耦接至第一电压V1，偏置晶体管MV并依据偏置信号VB来选择性地导通以提供电流给采样电路2043。第一电容C1的第二端耦接至第一电压和采样开关MH的源极，采样开关MH的漏极耦接至第二电容C2的第一端，第二电容C2的第二端耦接至第一电压V1。采样开关MH依据采样控制信号SH来选择性地导通，使第二电容C2的第一端选择性地耦接至选择晶体管MS1或选择晶体管MS2的漏极的其中之一。The sampling circuit 2043 of the pixel 204 includes a bias transistor MV, a first capacitor C1, a second capacitor C2, a sampling switch MH, a source follower transistor MF, and a row selection transistor MS. The sampling circuit 2043 is used to store the first sensing voltage and the second sensing voltage in the second capacitor C2 and the first capacitor C1 during the sampling operation. The drain of the bias transistor MV is coupled to the source of the selection transistor MS1 and the source of the selection transistor MS2, and the first end of the first capacitor C1. The source of the bias transistor MV is coupled to the first voltage V1, and the bias transistor MV is selectively turned on according to the bias signal VB to provide current to the sampling circuit 2043. The second terminal of the first capacitor C1 is coupled to the first voltage and the source of the sampling switch MH, the drain of the sampling switch MH is coupled to the first terminal of the second capacitor C2, and the second terminal of the second capacitor C2 is coupled To the first voltage V1. The sampling switch MH is selectively turned on according to the sampling control signal SH, so that the first terminal of the second capacitor C2 is selectively coupled to one of the drains of the selection transistor MS1 or the selection transistor MS2.
采样电路2043另包括源跟随晶体管MF和行选择晶体管MS，源跟随晶体管MF的栅极耦接至第二电容C2的所述第一端，源跟随晶体管MF的漏极耦接至第二电压V2，源跟随晶体管MF的漏极耦接至行选择晶体管MS的漏极，行选择晶体管MS依据行选择信号S来选择性地导通。The sampling circuit 2043 further includes a source follower transistor MF and a row selection transistor MS. The gate of the source follower transistor MF is coupled to the first terminal of the second capacitor C2, and the drain of the source follower transistor MF is coupled to the second voltage V2. , The drain of the source follower transistor MF is coupled to the drain of the row selection transistor MS, and the row selection transistor MS is selectively turned on according to the row selection signal S.
在本实施例中，晶体管皆为N型晶体管，且第二电压V2大于第一电压V1，也就是说，图2的实施例中，像素204中的所有晶体管的极性均相同。但本申请不以此限，在某些实施例中，像素204中的晶体管亦可以均为P型晶体管，且第一电压V1和第二电压V2的大小关系可作对应的调整。在某些实施例中，像素204中的晶体管可以同时具有N型晶体管和P型晶体管。In this embodiment, the transistors are all N-type transistors, and the second voltage V2 is greater than the first voltage V1. That is, in the embodiment of FIG. 2, all the transistors in the pixel 204 have the same polarity. However, the present application is not limited thereto. In some embodiments, the transistors in the pixel 204 can also be P-type transistors, and the magnitude relationship between the first voltage V1 and the second voltage V2 can be adjusted accordingly. In some embodiments, the transistors in the pixel 204 may have both N-type transistors and P-type transistors.
图3为本申请的光传感器103的像素204的操作实施例的流程图。如图3所示，在所述曝光操作一开始时，重置信号R1和重置信号R2会使第一电荷输出电路2041的源极输出SFO1(即所述第一感测电压)和第二电荷输出电路2042的源极输出SFO2(即所述第二感测电压)被重置，接著，在此次剩余的所述曝光操作中，光脉冲产生单元110的光脉冲信号EL会包括N个光脉冲，且第一电荷输出信号TX1和第二电荷输出信号TX2分别对应所述N个光脉冲中的每个光脉冲来导通开关MT1和开关MT2，以将反射信号RL对光电二极管PD造成的电荷导入第一电荷输出电路2041和第二电 荷输出电路2042，并累积成所述第一感测电压和所述第二感测电压，也就是说，N个光脉冲会对应N个第一电荷输出信号TX1和N个第二电荷输出信号TX1。在本实施例中，对应所述N个光脉冲中的每个光脉冲，开关MT2接续开关MT1导通，且开关MT1和开关MT2不会同时导通，或者说开关MT1和开关MT2的导通时间是错开的。FIG. 3 is a flowchart of an embodiment of the operation of the pixel 204 of the light sensor 103 of the present application. As shown in FIG. 3, at the beginning of the exposure operation, the reset signal R1 and the reset signal R2 cause the source of the first charge output circuit 2041 to output SFO1 (that is, the first sensing voltage) and the second The source output SFO2 (ie, the second sensing voltage) of the charge output circuit 2042 is reset. Then, in the remaining exposure operation, the light pulse signal EL of the light pulse generating unit 110 will include N Light pulses, and the first charge output signal TX1 and the second charge output signal TX2 respectively correspond to each of the N light pulses to turn on the switch MT1 and the switch MT2, so as to cause the reflected signal RL to the photodiode PD The charge is introduced into the first charge output circuit 2041 and the second charge output circuit 2042, and accumulated into the first sensing voltage and the second sensing voltage, that is, N light pulses will correspond to N first The charge output signal TX1 and N second charge output signals TX1. In this embodiment, corresponding to each of the N light pulses, the switch MT2 is connected to the switch MT1 to be turned on, and the switch MT1 and the switch MT2 will not be turned on at the same time, or the switch MT1 and the switch MT2 are turned on The time is staggered.
重置信号TXB则会在第一电荷输出信号TX1和第二电荷输出信号TX2使开关MT1和开关MT2导通以外的时间，对光电二极管PD进行重置，以降低累积到非反射信号RL所产生的电荷的机会。在曝光操作期间，采样电路2043中偏置信号VB使得偏置晶体管MV截止，采样电路2043不进行采样。接著，在所述采样操作中，偏置信号VB会导通偏置晶体管MV，且第一选择控制信号FD1会导通选择晶体管MS1，采样控制信号SH_i(SH_i表示第i行的采样控制信号SH)会导通采样开关MH，这样一来，所述第一感测电压便可输出至第一电容C1和第二电容C2，使第一电容C1和第二电容C2均具有所述第一感测电压。接著，第二选择控制信号FD2会导通选择晶体管MS2，采样控制信号SH_i不导通采样开关MH，这样一来，所述第二感测电压便可输出至第一电容C1而不输出至第二电容C2，而仅使第一电容C1具有所述第二感测电压，第二电容C2则保持所述第一感测电压。The reset signal TXB resets the photodiode PD when the first charge output signal TX1 and the second charge output signal TX2 turn on the switch MT1 and the switch MT2 to reduce the accumulation of the non-reflected signal RL. The chance of charge. During the exposure operation, the bias signal VB in the sampling circuit 2043 turns off the bias transistor MV, and the sampling circuit 2043 does not perform sampling. Then, in the sampling operation, the bias signal VB will turn on the bias transistor MV, and the first selection control signal FD1 will turn on the selection transistor MS1, and the sampling control signal SH_i (SH_i represents the sampling control signal SH of the i-th row). ) Will turn on the sampling switch MH, so that the first sensing voltage can be output to the first capacitor C1 and the second capacitor C2, so that both the first capacitor C1 and the second capacitor C2 have the first sense Measure the voltage. Then, the second selection control signal FD2 turns on the selection transistor MS2, and the sampling control signal SH_i does not turn on the sampling switch MH. In this way, the second sensing voltage can be output to the first capacitor C1 but not to the first capacitor C1. Two capacitors C2, so that only the first capacitor C1 has the second sensing voltage, and the second capacitor C2 maintains the first sensing voltage.
接著在所述读出操作时，偏置信号VB会先使偏置晶体管MV不导通，接著，行选择信号S会使行选择晶体管MS导通，并从第二电容C2读出所述第一感测电压至读取电路105。接著采样控制信号SH_i会导通，由于第一选择控制信号FD1和第二选择控制信号FD2并没有使选择晶体管MS1和选择晶体管MS2导通，因此第一电容C1和第二电容C2的电压会彼此达到平衡至所述第一感测电压和所述第二感测电压的平均值，并且被读出至读取电路105。Next, during the read operation, the bias signal VB will first make the bias transistor MV non-conducting, and then the row selection signal S will turn on the row selection transistor MS, and the second capacitor C2 is read from the second capacitor C2. A sensed voltage is sent to the reading circuit 105. Then the sampling control signal SH_i will be turned on. Since the first selection control signal FD1 and the second selection control signal FD2 do not turn on the selection transistor MS1 and the selection transistor MS2, the voltages of the first capacitor C1 and the second capacitor C2 will be different from each other. The balance is reached to the average value of the first sensing voltage and the second sensing voltage, and is read to the reading circuit 105.
在此实施例中，在所述读出操作的过程会一行一行的把像素阵列104的每一行像素的感测结果都读出，因此，图3中绘示了第i+1 行的采样控制信号SH_i+1和第i+2行的采样控制信号SH_i+2，在此仅为示例性表示，故其馀行的采样控制信号并没有一一绘示于图3。由于每一列像素共用一个读取电路105，故每一行的采样控制信号控制第一电容C1和第二电容C2的输出的操作不可同时进行，也就是说，第i行的采样控制信号SH_i、第i+1行的采样控制信号SH_i+1、第i+2行的采样控制信号SH_i+2和其他行的采样控制信号要错开，且每一行的采样控制信号使采样开关MH结束导通的时间点和下一行采样控制信号使采样开关MH开始导通的时间点至少要间隔足够长的时间让所述第一感测电压输出。In this embodiment, in the process of the readout operation, the sensing results of each row of pixels of the pixel array 104 are read out line by line. Therefore, FIG. 3 shows the sampling control of the i+1th line. The signal SH_i+1 and the sampling control signal SH_i+2 of the i+2th row are only exemplary representations, so the sampling control signals of the remaining rows are not shown in FIG. 3 one by one. Since each column of pixels shares a reading circuit 105, the operation of controlling the output of the first capacitor C1 and the second capacitor C2 by the sampling control signal of each row cannot be performed at the same time, that is, the sampling control signal SH_i of the i-th row and the first capacitor C2 The sampling control signal SH_i+1 of row i+1, the sampling control signal SH_i+2 of row i+2, and the sampling control signal of other rows should be staggered, and the sampling control signal of each row makes the sampling switch MH finish conducting time The point and the time point at which the sampling control signal of the next row makes the sampling switch MH start to be turned on must be at least sufficiently long for the first sensing voltage to be output.
由第3图可知，由于有采样电路2043暂存所述第一感测电压和所述第二感测电压，所述读出操作不会受到下一个曝光操作的影响，因此所述读出操作可以和所述下一个曝光操作同时进行，换句话说，所述曝光操作亦可和上一读出操作同时进行。和习知的光传感器的的操作相比，可节省额外的读出操作的时间。It can be seen from FIG. 3 that, because the sampling circuit 2043 temporarily stores the first sensing voltage and the second sensing voltage, the readout operation will not be affected by the next exposure operation, so the readout operation It can be performed simultaneously with the next exposure operation, in other words, the exposure operation can also be performed simultaneously with the previous readout operation. Compared with the operation of the conventional light sensor, additional time for the readout operation can be saved.
读取电路105从第二电容C2先后读出所述第一感测电压以及所述第一感测电压和所述第二感测电压的平均值后，会产生读取结果以响应所述第一感测电压以及所述第一感测电压和所述第二感测电压的平均值之间的差值，即所述第一感测电压-(所述第一感测电压+所述第二感测电压)/2，即(所述第一感测电压-所述第二感测电压)/2。关于读取电路105的实施方式请参考图1，读取电路105包括放大器106、模数转换器108和运算单元110。在此实施例中，放大器106可用来增强先后读出所述第一感测电压以及所述第一感测电压和所述第二感测电压的平均值，模数转换器108用来对放大器106增强后的所述第一感测电压以及所述第一感测电压和所述第二感测电压的平均值进行模数转换，运算单元110则用来对经过模数转换后的增强后的所述第一感测电压以及所述第一感测电压和所述第二感测电压的平均值进行模数转换进行差值运算。The reading circuit 105 successively reads the first sensing voltage and the average value of the first sensing voltage and the second sensing voltage from the second capacitor C2, and then generates a read result in response to the first sensing voltage. A sensed voltage and the difference between the average value of the first sensed voltage and the second sensed voltage, that is, the first sensed voltage-(the first sensed voltage + the first sensed voltage) Two sensing voltage)/2, that is, (the first sensing voltage-the second sensing voltage)/2. Please refer to FIG. 1 for the implementation of the reading circuit 105. The reading circuit 105 includes an amplifier 106, an analog-to-digital converter 108, and an arithmetic unit 110. In this embodiment, the amplifier 106 can be used to enhance the readout of the first sensing voltage and the average value of the first sensing voltage and the second sensing voltage, and the analog-to-digital converter 108 can be used to control the amplifier 106 The enhanced first sensing voltage and the average value of the first sensing voltage and the second sensing voltage perform analog-to-digital conversion, and the arithmetic unit 110 is used to perform analog-to-digital conversion on the enhanced analog-to-digital conversion The first sensing voltage and the average value of the first sensing voltage and the second sensing voltage are subjected to analog-to-digital conversion for difference calculation.
图4为本申请电子装置的实施例的示意图。电子装置400用以进行测距，电子装置400包括基于飞行时间的测距***100，在某 些实施例中。其中，电子装置400可为例如智能型手机、个人数字助理、手持式计算机***或平板计算机等任何电子装置。FIG. 4 is a schematic diagram of an embodiment of an electronic device of this application. The electronic device 400 is used for ranging, and the electronic device 400 includes a time-of-flight based ranging system 100, in some embodiments. The electronic device 400 may be any electronic device such as a smart phone, a personal digital assistant, a handheld computer system, or a tablet computer.
以上所述仅为本发明的优选实施例而已，并不用于限制本发明，对于本领域的技术人员来说，本发明可以有各种更改和变化。凡在本发明的精神和原则之内，所作的任何修改、等同替换、改进等，均应包括在本发明的保护范围之内。The above descriptions are only preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims (16)

  1. 一种光传感器，用以感测光脉冲产生单元所发送的光脉冲信号被目标物反射所产生的反射信号，其特征在于，所述光传感器包括：A light sensor for sensing a reflected signal generated by a light pulse signal sent by a light pulse generating unit being reflected by a target, characterized in that the light sensor includes:
    像素阵列，包括多个像素，所述多个像素中的每一像素包括：The pixel array includes a plurality of pixels, and each pixel of the plurality of pixels includes:
    光电二极管，用于在曝光操作时，传感所述反射信号以产生电荷；A photodiode for sensing the reflected signal to generate electric charge during exposure operation;
    第一电荷输出电路，用以根据第一电荷输出信号选择性地耦接于所述光电二极管，以产生第一感测电压；A first charge output circuit for selectively coupling to the photodiode according to a first charge output signal to generate a first sensing voltage;
    第二电荷输出电路，用以根据第二电荷输出信号选择性地耦接于所述光电二极管，以产生第二感测电压，其中所述第二电荷输出信号和所述第一电荷输出信号具有不同的相位；以及A second charge output circuit for selectively coupling to the photodiode according to a second charge output signal to generate a second sensing voltage, wherein the second charge output signal and the first charge output signal have Different phases; and
    采样电路，包括：Sampling circuit, including:
    第一电容，所述第一电容的第一端耦接于所述第一电荷输出电路和所述第二电荷输出电路，所述第一电容的第二端耦接于第一电压；A first capacitor, a first end of the first capacitor is coupled to the first charge output circuit and the second charge output circuit, and a second end of the first capacitor is coupled to a first voltage;
    采样开关，依据采样控制信号选择性地导通；以及The sampling switch is selectively turned on according to the sampling control signal; and
    第二电容，所述第二电容的第一端通过所述采样开关选择性地耦接于所述第一电荷输出电路、所述第二电荷输出电路和所述第一电容的所述第一端，所述第二电容的第二端耦接于所述第一电压。A second capacitor, the first terminal of the second capacitor is selectively coupled to the first charge output circuit, the second charge output circuit, and the first capacitor of the first capacitor through the sampling switch. The second terminal of the second capacitor is coupled to the first voltage.
  2. 如权利要求1所述的光传感器，其特征在于，在采样操作时，所述第二电容的电压为所述第一感测电压，所述第一电容的电压为所述第二感测电压。The photosensor according to claim 1, wherein during the sampling operation, the voltage of the second capacitor is the first sensing voltage, and the voltage of the first capacitor is the second sensing voltage .
  3. 如权利要求2所述的光传感器，其特征在于，所述第一电荷输出电路和所述第二电荷输出电路各包括选择晶体管，所述第一电荷输出电路的所述选择晶体管依据第一选择控制信号来选择性 地将所述第一感测电压耦接至所述采样电路；所述第二电荷输出电路的所述选择晶体管依据第二选择控制信号来选择性地将所述第二感测电压耦接至所述采样电路。The photosensor of claim 2, wherein the first charge output circuit and the second charge output circuit each comprise a selection transistor, and the selection transistor of the first charge output circuit is based on the first selection Control signal to selectively couple the first sensing voltage to the sampling circuit; the selection transistor of the second charge output circuit to selectively couple the second sensing voltage according to a second selection control signal The measured voltage is coupled to the sampling circuit.
  4. 如权利要求3所述的光传感器，其特征在于，在所述采样操作时，所述第一电荷输出电路的所述选择晶体管导通，所述第二电荷输出电路的所述选择晶体管不导通，且所述采样开关导通，使所述第一电容和所述第二电容均具有所述第一感测电压。The photosensor of claim 3, wherein, during the sampling operation, the selection transistor of the first charge output circuit is turned on, and the selection transistor of the second charge output circuit is not turned on. And the sampling switch is turned on, so that both the first capacitor and the second capacitor have the first sensing voltage.
  5. 如权利要求4所述的光传感器，其特征在于，在所述采样操作时，当所述第一电容和所述第二电容均具有所述第一感测电压时，所述第一电荷输出电路的所述选择晶体管不导通，所述第二电荷输出电路的所述选择晶体管导通，且所述采样开关不导通，使所述第一电容具有所述第二感测电压。The photosensor of claim 4, wherein, in the sampling operation, when the first capacitor and the second capacitor both have the first sensing voltage, the first charge output The selection transistor of the circuit is not turned on, the selection transistor of the second charge output circuit is turned on, and the sampling switch is not turned on, so that the first capacitor has the second sensing voltage.
  6. 如权利要求5所述的光传感器，其特征在于，所述采样电路另包括行选择晶体管，用于在读出操作时输出所述第一感测电压。8. The photosensor of claim 5, wherein the sampling circuit further comprises a row selection transistor for outputting the first sensing voltage during a readout operation.
  7. 如权利要求6所述的光传感器，其特征在于，在所述读出操作时，当所述第一电容和所述第二电容分别具有所述第二感测电压和所述第一感测电压时，所述采样开关导通，使所述第一电容和所述第二电容均具有所述第一感测电压和所述第二感测电压的平均值。The photosensor of claim 6, wherein in the readout operation, when the first capacitor and the second capacitor have the second sensing voltage and the first sensing voltage, respectively When the voltage is applied, the sampling switch is turned on, so that both the first capacitor and the second capacitor have an average value of the first sensing voltage and the second sensing voltage.
  8. 如权利要求7所述的光传感器，其特征在于，所述采样电路的所述行选择晶体管另用于在所述读出操作时输出所述第一感测电压和所述第二感测电压的平均值。The photosensor of claim 7, wherein the row selection transistor of the sampling circuit is further used to output the first sensing voltage and the second sensing voltage during the readout operation average value.
  9. 如权利要求8所述的光传感器，其特征在于，其中所述第一电荷输出电路和所述第二电荷输出电路分别另包括：8. The photosensor of claim 8, wherein the first charge output circuit and the second charge output circuit respectively further comprise:
    开关，用于依据所述第一电荷输出信号选择性地导通；以及A switch for selectively turning on according to the first charge output signal; and
    源跟随晶体管，其栅极通过所述开关选择性地耦接至所述光电二极管，所述源跟随晶体管的源/漏极通过所述选择晶体管选择性地耦接至所述采样电路。A source follower transistor whose gate is selectively coupled to the photodiode through the switch, and a source/drain of the source follower transistor is selectively coupled to the sampling circuit through the selection transistor.
  10. 如权利要求1所述的光传感器，其特征在于，所述多个像素中的每一像素另包括第一重置晶体管，耦接于所述光电二极管和第二电压之间，用于选择性地重置所述光电二极管。The photosensor of claim 1, wherein each pixel of the plurality of pixels further comprises a first reset transistor, coupled between the photodiode and a second voltage, for selective To reset the photodiode.
  11. 如权利要求9所述的光传感器，其特征在于，所述采样电路另包括：9. The light sensor according to claim 9, wherein the sampling circuit further comprises:
    源跟随晶体管，其栅极耦接至所述第二电容的所述第一端。The source follower transistor has its gate coupled to the first end of the second capacitor.
  12. 如权利要求2所述的光传感器，其特征在于，所述光传感器另包括：3. The light sensor according to claim 2, wherein the light sensor further comprises:
    读取电路，耦接至所述像素阵列，用于在所述读出操作时产生读取结果以响应所述第一感测电压以及所述第一感测电压和所述第二感测电压的平均值之间的差值。A reading circuit, coupled to the pixel array, for generating a reading result in response to the first sensing voltage and the first sensing voltage and the second sensing voltage during the readout operation The difference between the average values.
  13. 如权利要求1所述的光传感器，其特征在于，所述第一电荷输出信号和所述第二电荷输出信号的相位差是180度。8. The photosensor of claim 1, wherein the phase difference between the first charge output signal and the second charge output signal is 180 degrees.
  14. 一种基于飞行时间的测距***，其特征在于，包括：A distance measurement system based on flight time, which is characterized in that it includes:
    如权利要求1-13中任一项所述的光传感器；以及The light sensor according to any one of claims 1-13; and
    所述光脉冲产生单元。The light pulse generating unit.
  15. 一种电子装置，其特征在于，所述电子装置包括：An electronic device, characterized in that the electronic device comprises:
    如权利要求1-13中任一项所述的光传感器。The light sensor according to any one of claims 1-13.
  16. 一种电子装置，其特征在于，所述电子装置包括：An electronic device, characterized in that the electronic device comprises:
    如权利要求14所述的基于飞行时间的测距***。The distance measurement system based on time of flight according to claim 14.
PCT/CN2019/110336 2019-10-10 2019-10-10 Optical sensor, ranging system based on time of flight, and electronic apparatus WO2021068156A1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
CN201980004445.8A CN111108411B (en) 2019-10-10 2019-10-10 Optical sensor, time-of-flight-based ranging system and electronic device
PCT/CN2019/110336 WO2021068156A1 (en) 2019-10-10 2019-10-10 Optical sensor, ranging system based on time of flight, and electronic apparatus

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/CN2019/110336 WO2021068156A1 (en) 2019-10-10 2019-10-10 Optical sensor, ranging system based on time of flight, and electronic apparatus

Publications (1)

Publication Number Publication Date
WO2021068156A1 true WO2021068156A1 (en) 2021-04-15

Family

ID=70427392

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2019/110336 WO2021068156A1 (en) 2019-10-10 2019-10-10 Optical sensor, ranging system based on time of flight, and electronic apparatus

Country Status (2)

Country Link
CN (1) CN111108411B (en)
WO (1) WO2021068156A1 (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3955025A4 (en) * 2020-06-08 2022-04-13 Shenzhen Goodix Technology Co., Ltd. Time-of-flight-based ranging method and related ranging system
CN111427052B (en) * 2020-06-09 2020-11-27 深圳市汇顶科技股份有限公司 Ranging method based on flight time and related ranging system

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005127835A (en) * 2003-10-23 2005-05-19 Olympus Corp Photodetection system and distance measuring device using it
CN202261578U (en) * 2011-09-23 2012-05-30 东南大学 Active passive imaging reading circuit of avalanche photo diode (APD) array
CN107247269A (en) * 2017-06-11 2017-10-13 西安飞芯电子科技有限公司 For the detection device of acquisition process laser signal, pixel cell and array
CN108064446A (en) * 2017-10-20 2018-05-22 深圳市汇顶科技股份有限公司 Simulate reading circuit and image sensing module
CN208028993U (en) * 2018-01-31 2018-10-30 深圳市光微科技有限公司 Pixel unit, image sensor chip and imaging system
CN110168398A (en) * 2018-07-18 2019-08-23 深圳市汇顶科技股份有限公司 Range-measurement system and bearing calibration when flying

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
IL212289A (en) * 2011-04-13 2016-08-31 Semi-Conductor Devices - An Elbit Systems - Rafael Partnership Detector pixel signal readout circuit and an imaging method thereof
US8686367B2 (en) * 2012-03-01 2014-04-01 Omnivision Technologies, Inc. Circuit configuration and method for time of flight sensor
US9523765B2 (en) * 2014-07-14 2016-12-20 Omnivision Technologies, Inc. Pixel-level oversampling for a time of flight 3D image sensor with dual range measurements
US10291895B2 (en) * 2016-10-25 2019-05-14 Omnivision Technologies, Inc. Time of flight photosensor
US10663565B2 (en) * 2017-09-19 2020-05-26 Rockwell Automation Technologies, Inc. Pulsed-based time of flight methods and system
CN108282626B (en) * 2018-03-01 2021-04-23 思特威(上海)电子科技股份有限公司 TOF image sensor pixel structure and TOF imaging system

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005127835A (en) * 2003-10-23 2005-05-19 Olympus Corp Photodetection system and distance measuring device using it
CN202261578U (en) * 2011-09-23 2012-05-30 东南大学 Active passive imaging reading circuit of avalanche photo diode (APD) array
CN107247269A (en) * 2017-06-11 2017-10-13 西安飞芯电子科技有限公司 For the detection device of acquisition process laser signal, pixel cell and array
CN108064446A (en) * 2017-10-20 2018-05-22 深圳市汇顶科技股份有限公司 Simulate reading circuit and image sensing module
CN208028993U (en) * 2018-01-31 2018-10-30 深圳市光微科技有限公司 Pixel unit, image sensor chip and imaging system
CN110168398A (en) * 2018-07-18 2019-08-23 深圳市汇顶科技股份有限公司 Range-measurement system and bearing calibration when flying

Also Published As

Publication number Publication date
CN111108411A (en) 2020-05-05
CN111108411B (en) 2021-06-08

Similar Documents

Publication Publication Date Title
JP7374242B2 (en) Dynamic vision sensor architecture
CN100515050C (en) Solid-state image pickup device, method of driving same and imaging apparatus
US5479208A (en) Image sensors and driving method thereof
US20150156433A1 (en) Semiconductor device, physical information acquiring apparatus, and signal reading-out method
JP2020505855A (en) Imaging array with extended dynamic range
US8520106B2 (en) Solid-state imaging device with improved dynamic range
US9549138B2 (en) Imaging device, imaging system, and driving method of imaging device using comparator in analog-to-digital converter
JP5685927B2 (en) Infrared detection circuit, sensor device and electronic equipment
KR20040011836A (en) Analog to didital converter for cmos image device
US20160037095A1 (en) Active pixel sensor device and operating method of the same
WO2021068156A1 (en) Optical sensor, ranging system based on time of flight, and electronic apparatus
JP2011174919A (en) Detection circuit for thermal sensor, thermal sensor device, and electronic device
US11233967B2 (en) AD conversion circuit, imaging device, and endoscope system
CN102487436A (en) Sensing pixel array and sensing apparatus
JP2011174918A (en) Detection device, sensor device, and electronic apparatus
US8432471B2 (en) CMOS image sensor and image signal detecting method
EP2773099B1 (en) Image pickup apparatus, driving method for image pickup apparatus, image pickup system, and driving method for image pickup system
KR20210055821A (en) Sensor operating based on measuring range of depth and sensing system including the same
TW201304534A (en) Semiconductor device and method for driving the same
CN212031730U (en) Optical sensor, time-of-flight-based ranging system and electronic device
JP7048448B2 (en) Solid-state image sensor
CN111757025B (en) Electronic device
JP2013069201A (en) Optical sensor, driving method thereof, vein sensor and fingerprint sensor
US10187598B2 (en) Circuit for reading-out voltage variation of floating diffusion area, method thereof and CMOS image sensor using the same
KR20190106516A (en) Single-slope comparator with high-resolution and low-noise, and cmos image sensor thereof

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: 19948683

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: 19948683

Country of ref document: EP

Kind code of ref document: A1