Structure and implementation method of discontinuous exposure image sensor pixel circuit

Abstract

The invention discloses a structure and an implementation method of a discontinuous exposure image sensor pixel circuit. The image sensor pixel circuit comprises a photosensitive module, a transmission module, a storage module, a reset module, a reset storage module, a lossless recharge module and an output module, the image sensor pixel circuit supports pulse light emitted by an external pulse light source to serve as an exposure light source, and sensitizes, stores and accumulates a discontinuous exposure gap exposure environment. The lossless recharging module is used for recharging the light sensing level signal stored after last gap exposure to the light sensing module without loss before new gap exposure, so that the light sensing module starts the accumulation of the current pulse exposure on the basis of the exposure result of the last pulse signal; the image sensor pixel circuit supports a gap exposure environment of dozens of times to tens of thousands of times per frame, enhances the acquisition capability of environment images at different distances, adapts to various weather conditions, and improves the perceptual performance of the images.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor image sensing technology, image sensor chips and image sensors, and in particular to a structure and implementation method of a non-continuous exposure image sensor pixel circuit. Background Art

[0002] The imaging capability of a camera is mainly determined by the perception capability of its image sensor. The image sensor receives external light and converts the optical signal into an electrical signal to obtain an image. At night, the perception capability of the image sensor is greatly reduced due to the dimming of the light. In severe weather conditions such as rain, fog, and snow, the light reflected by objects and the environment is blocked by rain, fog, and snow, which greatly reduces the perception performance of existing image sensors.

[0003] In the prior art, image sensors generally use two exposure methods, namely rolling exposure or global exposure, to collect image signals. In addition, during the photosensitivity time of each frame, each pixel of the image uses a continuous exposure method to collect image signals, and after exposure, the image is output in a rolling or full frame format. As described in the invention patent application No. 201810172280.2, "HDR Image Sensor Pixel Structure and Imaging System Supporting Multiple Exposure Modes", whether it is rolling exposure or global exposure, the exposure time within a frame is continuous exposure, and after exposure, the image is output in a rolling or full frame format;

[0004] As described in the invention patent application No. 201410635661.1, "10T global shutter pixel unit and its signal acquisition method and manufacturing method", the patent uses 10 MOS switch tubes for signal reading circuit, signal holding circuit and signal output circuit respectively; as described in the invention patent application No. 201210045638.8, "A pixel structure and its multiple exposure method", the patent controls the discharge degree of photogenerated charge in the photodiode through gate voltage, realizes the intra-pixel superposition method of multiple exposure signals, and eliminates the digital circuit part of multiple readouts and re-fusion; these two patents are not for cooperating with the exposure of external light sources, so their pixel structures, implementation methods, purposes and functions are different from this patent.

[0005] In order to improve the image signal of the image sensor at night and in low light conditions, one technology is to enhance the ambient light through a continuous infrared fill light module. This method can only see the close environment clearly. Another technology is to increase the exposure time as much as possible, and increase the light flux through more cumulative exposure than the existing technology. This technical solution has a low image frame rate and it is difficult to balance the brightness of objects at both near and far distances. It is also not suitable for application scenarios such as autonomous driving of cars that have strict requirements on the delay of image acquisition. Summary of the invention

[0006] The purpose of the present invention is to adjust the pixel circuit structure of the photosensitive pixel unit of the image sensor chip so that it can realize a high-frequency discontinuous intermittent exposure function within the photosensitivity time of one frame, so as to cooperate with a short-time high-power pulse light source. While taking into account the tolerance of the human eye, it is possible to improve the image perception performance at night and in severe weather conditions, thereby realizing a camera with all-weather imaging capabilities.

[0007] To achieve the above-mentioned purpose, the structure and implementation method of the non-continuous exposure image sensor pixel circuit are characterized by:

[0008] The pixel circuit used by each photosensitive pixel unit of the image sensor chip ( Figure 1 The structure of 100) is divided into the following according to the functions: photosensitive module ( Figure 1 1) Transmission module ( Figure 1 2), storage module ( Figure 1 3) Reset module ( Figure 1 4) Reset the storage module ( Figure 1 5) Lossless recharging module ( Figure 1 6), and output modules ( Figure 1 7); the photosensitive pixel unit supports the pulse light emitted by the external pulse light source as the exposure light source; the exposure performed by the photosensitive pixel unit corresponding to each pulse light source is an intermittent exposure;

[0009] The photosensitive module ( Figure 1 1) for sensing external light and pulse reflected light emitted by an external pulse light source and then reflected from an object and reaching the image sensor chip; the reset module ( Figure 1 The reset level of 4) can be directly input to the photosensitive module ( Figure 1 1) to reset; or through the storage module ( Figure 1 3), the transmission module ( Figure 1 2) input to the photosensitive module ( Figure 1 1) to reset; or through the lossless recharging module ( Figure 1 6), the storage module ( Figure 1 3), the transmission module ( Figure 1 2) input to the photosensitive module ( Figure 1 1) is reset, at which time the lossless recharging module ( Figure 1 6) is in a reset state; the lossless recharging module ( Figure 1 6) and the photosensitive module ( Figure 1 1) is connected, when necessary, the lossless recharging module ( Figure 1 6) The storage module ( Figure 13) The final accumulated light sensitivity level signal after the last intermittent exposure stored is input to the light sensing module ( Figure 1 1), at this time, the lossless recharging module ( Figure 1 6) is in a lossless driving state; the photosensitive module ( Figure 1 1) and the transmission module ( Figure 1 2) is connected, when necessary, the photosensitive module ( Figure 1 1) outputting the accumulated sensitivity level signal after each intermittent exposure or the final accumulated sensitivity level signal to the transmission module ( Figure 1 2);

[0010] The transmission module ( Figure 1 2) is used for a gap exposure or a frame exposure after the photosensitive module ( Figure 1 1) The final accumulated photosensitivity level signal saved is transmitted to the storage module ( Figure 1 3); transmission control signal ( Figure 1 10) and the transmission module ( Figure 1 2) is connected to control the transmission module ( Figure 1 2) is turned on and off; when necessary, the transmission module ( Figure 1 2) outputting the light-sensitivity level signal to the storage module ( Figure 1 3);

[0011] The storage module ( Figure 1 3) is used to store the final accumulated photosensitivity level signal after each intermittent exposure or after one frame exposure, and the storage medium is a capacitor; the storage module ( Figure 1 The storage capacitor for storing the photosensitive level signal in 3) may be more than one, which are respectively used for storing the photosensitive level signals of the intermittent exposure at different times, and different capacitors have independent electronic switches; when the photosensitive level signal is received from the photosensitive module ( Figure 1 1) is transmitted to the storage module ( Figure 1 3) in the process, as described in the storage module ( Figure 1 3) The storage capacitor in the photosensitive module ( Figure 1 When the light-sensing level signal in 1) has little influence, the transmission module ( Figure 1 2) directly with the storage module ( Figure 1 3) and can directly transmit the light-sensing level signal to the storage module ( Figure 1 3) for storage; when the light-sensing level signal needs to be received from the light-sensing module ( Figure 1 1) is transmitted to the storage module ( Figure 1 3), when the storage module ( Figure 1 3) The storage capacitor in the photosensitive module ( Figure 1 When the light-sensing level signal in 1) has a greater impact, the transmission module ( Figure 1 2) directly with the lossless recharging module ( Figure 1 6) is connected, the storage module ( Figure 1 3) are respectively connected to the lossless recharging module ( Figure 1 6) and the transmission module ( Figure 1 2) is connected, the transmission module ( Figure 1 2) first transmit the light-sensing level signal to the lossless recharging module ( Figure 1 6), and then the lossless recharging module ( Figure 1 6) losslessly driving the light-sensing level signal and then storing it in the storage module ( Figure 1 3) for storage, at which time the lossless recharging module ( Figure 1 6) is in a lossless drive state; when necessary, the storage module ( Figure 1 3) through the lossless recharging module ( Figure 1 6) feeding the light-sensing level signal back to the light-sensing module ( Figure 1 1); when necessary, the storage module ( Figure 1 3) through the lossless recharging module ( Figure 1 6) outputting the light-sensitivity level signal to the output module ( Figure 1 7), at this time, the lossless recharging module ( Figure 1 6) in a lossy drive state or a lossless drive state as required;

[0012] The reset module ( Figure 1 4) is used to initialize the photosensitive module ( Figure 1 1), the storage module ( Figure 1 3), the reset storage module ( Figure 1 5) and the lossless recharging module ( Figure 1 6) to reset; reset control signal ( Figure 1 20) and the reset module ( Figure 1 4) is connected to control the reset module ( Figure 1 4) opening and closing; the reset module ( Figure 1 4) and the photosensitive module ( Figure 1 There are two ways to connect the reset module ( Figure 1 4) directly with the photosensitive module ( Figure 1 1) is connected through an electronic switch, and the reset level is determined by the reset module ( Figure 1 4) is directly transmitted to the photosensitive module ( Figure 1 1); secondly, the reset module ( Figure 14) and the lossless recharging module ( Figure 1 6), the storage module ( Figure 1 3), the transmission module ( Figure 1 2) is connected through an electronic switch, and the reset level is reset through the lossless recharging module ( Figure 1 6), the storage module ( Figure 1 3), the transmission module ( Figure 1 2) and then transmitted to the photosensitive module ( Figure 1 1); the reset module ( Figure 1 4) and the storage module ( Figure 1 3), the reset storage module ( Figure 1 5) and the lossless recharging module ( Figure 1 6) are connected via an electronic switch; when a reset is required, the reset module ( Figure 1 4) outputting the reset level to the photosensitive module ( Figure 1 1), the storage module ( Figure 1 3), the reset storage module ( Figure 1 5) and the lossless recharging module ( Figure 1 6) and reset;

[0013] The reset storage module ( Figure 1 5) is used to initialize the photosensitive module ( Figure 1 1) reset level signal for storage; reset storage control signal ( Figure 1 30) and the reset storage module ( Figure 1 5) is connected to control the reset storage module ( Figure 1 5) opening and closing; when necessary, the reset storage module ( Figure 1 5) reads the reset level signal and stores it; when necessary, the reset storage module ( Figure 1 5) the stored reset level signal is sent through the lossless recharging module ( Figure 1 6) and the output module ( Figure 1 7) output to the column output bus ( Figure 1 8);

[0014] The lossless recharging module ( Figure 1 6) is used to store the data stored in the storage module ( Figure 1 The photosensitive level signal saved after the last intermittent exposure in 3) is fed back to the photosensitive module without loss ( Figure 1 1), so that the photosensitive module ( Figure 11) Returning to the light-sensing level signal saved after the last intermittent exposure, the accumulation of this new intermittent exposure is started, and the light-sensing module ( Figure 1 1) The unnecessary sensitivity level signal collected between two exposure intervals is thus cleared; lossless control signal ( Figure 1 50) and the lossless recharging module ( Figure 1 6) is connected, the lossless recharging module ( Figure 1 6) According to different functional requirements, open the lossless recharging module ( Figure 1 6) different switch tubes in order to achieve different functions, the lossless control signal ( Figure 1 50) is composed of a group of control signals of different switch tubes realizing different functions; the lossless recharging module ( Figure 1 6) includes a reset state, a disconnect state, a lossy drive state, and a lossless drive state; the reset state is used to reset a frame of exposure in the initial stage, or to charge the compensation capacitor required for lossless drive; in the disconnect state, the lossless recharge module ( Figure 1 6) The connection switches with other modules are all in the disconnected state, which is used for not needing the lossless recharging module ( Figure 1 6) generates a driving signal; in the lossy driving state, the lossless recharge module ( Figure 1 6) is in a lossy current enhancement driving state, and can be used for output driving after a frame of exposure when necessary; in the lossless driving state, the lossless recharge module ( Figure 1 6) includes a current enhancement driving circuit and a compensation circuit for compensating for the level loss caused by the current enhancement driving circuit, and the level loss stored in the storage module ( Figure 1 The photosensitive level signal saved after the last intermittent exposure in 3) is fed back to the photosensitive module without loss ( Figure 1 1), or output drive for the end of one frame exposure; the lossless recharging module ( Figure 1 6) Whether to use the lossy driving state or the lossless driving state at the end of a frame depends on whether the final accumulated light sensitivity level signal after a frame of exposure can be correctly obtained in the back-end image processing, and the deviation is minimal;

[0015] The output module ( Figure 1 7) is used to take out the reset level signal and the light-sensitive level signal; the row selection control signal ( Figure 1 40) and the output module ( Figure 1 7) is connected to control the output module ( Figure 1 7) opening and closing; when necessary, through the output module ( Figure 1 7) respectively outputs the reset level signal and the light-sensitive level signal to the column output bus ( Figure 1 8);

[0016] The intermittent exposure means that when the pulse reflected light of an object within a set distance interval reaches the image sensor chip, the photosensitive module ( Figure 1 1) Turn on the light-sensing module. After the pulse reflected light passes through, the light-sensing module ( Figure 1 1) Ending this exposure and transmitting the light sensitivity level signal saved after this exposure to the transmission module ( Figure 1 2) output to the storage module ( Figure 1 3); the length of the gap exposure repetition period is equal to the length of the pulse light emission repetition period, and each gap exposure time interval is shorter than the gap exposure repetition period;

[0017] The method for accumulating the intermittent exposure signal is as follows: when the first arriving pulse reflection light echo signal within the set distance interval to be received next reaches the photosensitive module ( Figure 1 1), the lossless recharging module ( Figure 1 6) First, the storage module ( Figure 1 The previous exposure result stored in 3) is returned to the photosensitive module without loss ( Figure 1 1), then the photosensitive module ( Figure 1 1) based on the result of the last pulse reflected light exposure, the accumulation of the current pulse reflected light exposure is started; when the last pulse reflected light echo signal of the set distance range to be received is transmitted, the photosensitive module ( Figure 1 The perception result of 1) is transmitted through the transmission module ( Figure 1 2) transferred to the storage module ( Figure 1 3), and then the transmission module ( Figure 1 2) turn off the transmission; before the first gap exposure of a frame, the photosensitive module ( Figure 1 1) is reset, or the lossless recharging module ( Figure 1 6) returning the reset level to the photosensitive module without loss ( Figure 1 1).

[0018] Furthermore, the structure and implementation method of the non-continuous exposure image sensor pixel circuit are characterized by:

[0019] After a frame of exposure begins, the image sensor pixel circuit ( Figure 1 The exposure operation of 100) is based on the external mode control signal ( Figure 2 60) to select the conventional exposure mode or the intermittent exposure mode; when the image sensor pixel circuit ( Figure 1When the interval exposure mode is selected, the interval exposure timing generation circuit inside the image sensor chip outputs control signals to each functional module of each pixel in a certain timing to realize interval exposure; stage 1 ( Figure 2 1) and 2) Figure 2 2), stage 3( Figure 2 3) and 4 ( Figure 2 4) and 5 ( Figure 2 5) and 6 ( Figure 2 6), stage 7( Figure 2 7), stage 8( Figure 2 8) respectively represent the image sensor pixel circuit ( Figure 1 The eight working stages of 100) are:

[0020] Phase 1 Figure 2 1) is to reset and store the reset level signal: that is, the reset module ( Figure 1 4) After receiving the reset control signal, the reset module ( Figure 1 The reset tube in 4) is turned on, and the reset level is sent to the photosensitive module ( Figure 1 1), the storage module ( Figure 1 3), the lossless recharging module ( Figure 1 6) and the reset storage module ( Figure 1 5), used for the photosensitive module ( Figure 1 1) the photosensitive diode, the storage module ( Figure 1 3) The storage capacitor and the reset storage module ( Figure 1 5) in the storage capacitor is reset; at the same time, the photosensitive module ( Figure 1 1) and stores the level signal in the reset storage module ( Figure 1 The storage capacitor in 5) lasts for the set time corresponding to this stage;

[0021] Phase 2 Figure 2 2) is to sample the gate-source difference level and store it: that is, through the reset module ( Figure 1 4) and the lossless recharging module ( Figure 1 The voltage difference between the gate G and the source S of the source follower in 6) is collected and stored in the lossless recharge module ( Figure 1 6) Internal compensation capacitor;

[0022] Phase 3 Figure 2 3) before a new pulse of reflected light is about to arrive, the charge backflow operation is started and lasts for the set time corresponding to this stage: that is, through the lossless backflow module ( Figure 1 6) The storage module ( Figure 1 The photosensitive level signal in 3) is superimposed on the stored gate-source difference level (VGS), and then output to the photosensitive module ( Figure 1 1), realizing the lossless backflow of the last photosensitive level signal to the photosensitive module ( Figure 1 1) and stop after the set time of this stage;

[0023] Phase 4 Figure 2 4) is intermittent exposure and lasts for the set time corresponding to this stage: that is, the photosensitive module ( Figure 1 1) Based on the last photosensitivity level signal, the system enters the intermittent exposure period, accumulates and receives new pulse reflected light echo signals, and stops after the set time corresponding to this stage;

[0024] Phase 5 Figure 2 5) is for transmitting and storing the light-sensitivity level signal: that is, the transmission module ( Figure 1 2) Receive the transmission control signal ( Figure 1 10), through the transmission module ( Figure 1 2), and when necessary, through the lossless recharging module ( Figure 1 6) The photosensitive module ( Figure 1 1) The received light-sensing level signal is transferred to the storage module ( Figure 1 3) is stored;

[0025] Phase 6 Figure 2 6) is to turn off the switches of all modules: that is, the switches of all modules are in the off state, then the photosensitive module ( Figure 1 In 1), the light-sensitivity level signal received during the time of turning off the switches of all modules is not collected, stored, or accumulated; during this period, the interval exposure timing generation circuit in the image sensor chip determines whether the interval exposure in one frame is completed? If it is completed, enter stage 7 ( Figure 2 7); if it is not finished, return to stage 2 ( Figure 2 2);

[0026] Stage 7 Figure 2 7) is the waiting column output bus ( Figure 1 8) Read reset level signal: When needed, the output module ( Figure 1 The row select tube of 7) receives the row selection control signal ( Figure 1 After 40), the row selection tube is turned on, and the column output bus ( Figure 1 8) by resetting the storage module ( Figure 1 5), the lossless recharging module ( Figure 16) and the output module ( Figure 1 7) reading the reset level signal;

[0027] Stage 8 Figure 2 8) is the waiting column output bus ( Figure 1 8) Read the light-sensing level signal: When necessary, the output module ( Figure 1 The row select tube in 7) receives the row selection control signal ( Figure 1 After 40), the row selection tube is turned on, and the column output bus ( Figure 1 8) through the storage module ( Figure 1 3), the lossless recharging module ( Figure 1 6) and the output module ( Figure 1 7) read the storage module ( Figure 1 3) is a photosensitivity level signal; the difference between the photosensitivity level signal and the reset level signal is the image data signal of the image sensor pixel circuit.

[0028] Furthermore, the structure and implementation method of the non-continuous exposure image sensor pixel circuit are characterized by:

[0029] When the image sensor pixel circuit ( Figure 1 External mode control signal (100) Figure 1 When the intermittent exposure mode is not selected in step 60, the conventional exposure mode is entered, then step 11 ( Figure 2 11) and 12 ( Figure 2 12) and 13 ( Figure 2 13) and 14 ( Figure 2 14) and 15 ( Figure 2 15) respectively represent the image sensor pixel circuit ( Figure 1 The five working stages of 100) are:

[0030] Phase 11( Figure 2 11) is a reset and storage reset level signal: that is, the reset module ( Figure 1 4) Receive the reset control signal ( Figure 1 20), the reset module ( Figure 1 The reset tube in 4) is turned on, and the reset level is sent to the photosensitive module ( Figure 1 1), the storage module ( Figure 1 3), the lossless recharging module ( Figure 1 6) and the reset storage module ( Figure 1 5), used for the photosensitive module ( Figure 1 1) the photosensitive diode, the storage module ( Figure 13) The storage capacitor and the reset storage module ( Figure 1 5) in the storage capacitor is reset; at the same time, the photosensitive module ( Figure 1 1) and stores the reset level signal in the reset storage module ( Figure 1 5) of the storage capacitor; the reset time is set by the system;

[0031] Phase 12( Figure 2 12) is continuous exposure for the set time: that is, the photosensitive module ( Figure 1 1) Continuously receive and accumulate external light signals, and stop after the time set in this stage;

[0032] Phase 13( Figure 2 13) is used to transmit and store the light-sensitivity level signal: that is, the transmission module ( Figure 1 2) Receive the transmission control signal ( Figure 1 10), through the transmission module ( Figure 1 2), and when necessary, through the lossless recharging module ( Figure 1 6) The photosensitive module ( Figure 1 1) The received light-sensitivity level signal is transmitted to the storage module ( Figure 1 3) is stored;

[0033] Stage 14 Figure 2 14) is the waiting column output bus ( Figure 1 8) Read reset level signal: When needed, the output module ( Figure 1 The row select tube in 7) receives the row selection control signal ( Figure 1 After 40), the row selection tube is turned on, and the column output bus ( Figure 1 8) by resetting the storage module ( Figure 1 5), the lossless recharging module ( Figure 1 6), and the output module ( Figure 1 7) reads the reset level signal, at which time the lossless recharging module ( Figure 1 6) It can work in lossless drive state or lossy drive state as needed;

[0034] Stage 15( Figure 2 15) is the waiting column output bus ( Figure 1 8) Read the light-sensing level signal: When necessary, the output module ( Figure 1 The row select tube in 7) receives the row selection control signal ( Figure 1 After 40), the row selection tube is turned on, and the column output bus ( Figure 1 8) through the storage module ( Figure 1 3), the lossless recharging module ( Figure 1 6) and the output module ( Figure 1 7) read the storage module ( Figure 1 3) of the light-sensing level signal, at this time, the lossless recharging module ( Figure 1 6) It can work in a lossless driving state or a lossy driving state as needed; the difference between the photosensitivity level signal and the reset level signal is the image data signal of the image sensor pixel circuit.

[0035] Furthermore, the structure and implementation method of the non-continuous exposure image sensor pixel circuit are characterized by:

[0036] An image sensor pixel circuit supporting discontinuous exposure of a pulse light source is adopted ( Figure 1 The pulse light sources supported by the image sensor chip of 100 include laser, infrared light, visible light, and light of various wavelength bands.

[0037] Furthermore, the structure and implementation method of the non-continuous exposure image sensor pixel circuit are characterized by:

[0038] The image sensor pixel circuit supporting discontinuous exposure of a pulse light source ( Figure 1 The non-continuous exposure signal supported by 100) is a series of exposure pulse signals whose pulse width and period can be changed as needed.

[0039] Furthermore, the structure and implementation method of the non-continuous exposure image sensor pixel circuit are characterized by:

[0040] The image sensor pixel circuit supporting discontinuous exposure of a pulse light source ( Figure 1 100) supports global shutter image sensors and rolling shutter image sensors.

[0041] Furthermore, the structure and implementation method of the non-continuous exposure image sensor pixel circuit are characterized by:

[0042] Each pixel circuit of the image sensor ( Figure 1 The lossless recharging module (100) Figure 1 6) The error generated by each lossless recharge can be detected by a special calibration frame, in which the stage 1 ( Figure 2 1) reset cycle, and then repeat the stage 2 ( Figure 2 2), then execute the storage module ( Figure 1 The light-sensitive level signal stored in 3) is fed back through the lossless recharging circuit module ( Figure 16) to the photosensitive module ( Figure 1 1), then execute the stage 5 ( Figure 2 5), perform the three actions for a set number of repetitions, and finally go through the stage 7 ( Figure 2 7) and the stage 8 ( Figure 2 8), it can be obtained that after the set number of repetitions, the lossless recharge module ( Figure 1 6) produces an error; when the storage module ( Figure 1 3) includes a plurality of capacitors, and two of the capacitors can be used by the lossless recharging module ( Figure 1 6) when driven, the action in the calibration frame becomes: first execute the stage 1 ( Figure 2 1) reset cycle, and then repeat the stage 2 ( Figure 2 2), by the storage module ( Figure 1 The first capacitor of 3) is used as a signal source through the lossless recharge module ( Figure 1 6) for the storage module ( Figure 1 The second capacitor in 3) is losslessly recharged, and the recharged capacitor and the storage module ( Figure 1 The capacitor used as the signal source in step 3) is exchanged with the electronic switch, and the three actions are repeated for a set number of times, and finally the stage 7 ( Figure 2 7) and the stage 8 ( Figure 2 8), it can be obtained that after the set number of repetitions, the lossless recharge module ( Figure 1 6) A more accurate value of the error produced. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 A functional module diagram of the structure and implementation method of a non-continuous exposure image sensor pixel circuit of the present invention

[0044] Figure 2 The structure and implementation method of the non-continuous exposure image sensor pixel circuit of the present invention are flow charts of the working stages in two modes.

[0045] Figure 3 A schematic diagram of a non-continuous exposure image sensor pixel circuit provided in Embodiment 1 of the present invention

[0046] Figure 4 A flowchart of the working stages of a method for implementing a non-continuous exposure image sensor pixel circuit in two modes provided in Embodiment 1 of the present invention

[0047] Figure 5A schematic diagram of a timing control waveform of a non-continuous exposure image sensor pixel circuit in an intermittent exposure mode provided in the first embodiment of the present invention

[0048] Figure 6 A schematic diagram of a timing control waveform of a non-continuous exposure image sensor pixel circuit in a conventional exposure mode provided in Embodiment 1 of the present invention

[0049] Figure 7 A schematic diagram of a non-continuous exposure image sensor pixel circuit provided in the second embodiment of the present invention

[0050] Figure 8 A flowchart of the working stages of a method for implementing a non-continuous exposure image sensor pixel circuit in two modes provided in the second embodiment of the present invention

[0051] Fig. 9 A schematic diagram of a timing control waveform of a non-continuous exposure image sensor pixel circuit in an intermittent exposure mode provided in the second embodiment of the present invention

[0052] Fig.10 A schematic diagram of a timing control waveform of a non-continuous exposure image sensor pixel circuit in a normal mode provided in the second embodiment of the present invention DETAILED DESCRIPTION

[0053] The following embodiments of the technical solution of the present invention are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and are therefore only examples, and cannot be used to limit the protection scope of the present invention. Various modifications or applications made according to the embodiments are within the protection scope of this technical solution.

[0054] like Figure 3 , Figure 4 , Figure 5 , Figure 6 The figure shows the structure and implementation method of a non-continuous exposure image sensor pixel circuit provided by the first embodiment of the present invention:

[0055] like Figure 3 As shown, the pixel circuit components used in each photosensitive pixel unit of the image sensor chip include: a photosensitive diode, ten switching transistors, three storage capacitors and a current limiting resistor or a constant current source circuit; wherein the ten switching transistors are all NMOS tubes (or PMOS tubes), the three storage capacitors are all ordinary capacitors, and the current limiting resistor is an ordinary resistor; that is: the photosensitive diode ( Figure 3 D1), transmission tube ( Figure 3 Ttx), reset tube ( Figure 3 Trst), source follower ( Figure 3 Tsf), row gate tube ( Figure 3 Tsel), the first switch tube ( Figure 3 Tsw1), the second switch tube ( Figure 3 Tsw2), the third switch tube ( Figure 3 Tsw3), the fourth switch tube ( Figure 3 Tsw4), the fifth switch tube ( Figure 3 Tsw5), the sixth switch tube ( Figure 3 Tsw6), the first capacitor ( Figure 3 The second capacitor is the compensation capacitor ( Figure 3 C2), the third capacitor ( Figure 3 C3), the first resistor ( Figure 3 R1); and the drain D ( Figure 3 D), source S( Figure 3 S), gate G( Figure 3 G); Circuit connection points include: Node J1 ( Figure 3 Node J1), node J2 ( Figure 3 Node J2), node J3 ( Figure 3 Node J3), node J4 ( Figure 3 Node J4), node J5 ( Figure 3 J5); Output bus includes: Column output bus ( Figure 3 ColOutput); control signals include: TX ( Figure 3 10)-transmission control signal, RST ( Figure 3 20)-Reset control signal, SW5( Figure 3 30)-reset storage control signal, that is, the fifth switch signal, SEL ( Figure 3 40)-row selection control signal, lossless control signal ( Figure 3 50) includes SW1-first switch signal ( Figure 3 SW1), SW2- second switch signal ( Figure 3 SW2), SW3- the third switch signal ( Figure 3 SW3), SW4- the fourth switch signal ( Figure 3 SW4) and SW6-sixth switch signal ( Figure 3 SW6), and external mode control signal ( Figure 3 of 60);

[0056] The pixel circuit of the photosensitive pixel unit ( Figure 3 The structure of 100) is divided into the following according to the functions: photosensitive module ( Figure 3 1) Transmission module ( Figure 3 2), storage module ( Figure 3 3) Reset module ( Figure 34) Reset the storage module ( Figure 3 5) Lossless recharging module ( Figure 3 6), and output modules ( Figure 3 7);

[0057] The photosensitive module ( Figure 3 1), comprising the photodiode ( Figure 3 D1); the photodiode ( Figure 3 The negative terminal of D1 is connected to node J4 ( Figure 3 J4), its positive terminal is connected to the ground level;

[0058] The transmission module ( Figure 3 2), comprising the transmission tube ( Figure 3 Ttx); the transmission tube ( Figure 3 The drain D (or source S) of Ttx is connected to the node J4 ( Figure 3 J4), whose source S (or drain D) is connected to node J1 ( Figure 3 J1), by connecting its gate to the transmission control signal ( Figure 3 TX, 10) to control its conduction and cutoff;

[0059] The storage module ( Figure 3 3), including the first capacitor ( Figure 3 C1); the first capacitor ( Figure 3 One end of C1 is connected to the node J1 ( Figure 3 J1), the other end of which is connected to the ground level; when the storage module ( Figure 3 3) in the storage capacitor ( Figure 3 C1) to the photosensitive module ( Figure 3 When the light-sensing level signal in D1) is acceptable, the transmission module ( Figure 3 2) The light-sensitivity level signal can be directly transmitted to the storage module ( Figure 3 3) Storage capacitor first capacitor ( Figure 3 C1) for storage;

[0060] The reset module ( Figure 3 4), including the reset tube ( Figure 3 Trst); the reset tube ( Figure 3 The drain D (or source S) of Trst is connected to the power supply voltage 1 ( Figure 3 Vdd1), its source S (or drain D) is connected to node J2 ( Figure 3 J2), by connecting the reset control signal ( Figure 3 RST, 20) to control its conduction and cutoff;

[0061] The reset storage module ( Figure 3 5), including the fifth switch tube ( Figure 3 Tsw5), the third capacitor ( Figure 3 C3); the fifth switch tube ( Figure 3 The drain D (or source S) of Tsw5 is connected to the node J2 ( Figure 3 J2), whose source S (or drain D) is connected to the third capacitor ( Figure 3 C3) by connecting its gate to the reset storage control signal ( Figure 3 SW5, 30) to control its conduction and cutoff; the third capacitor ( Figure 3 One end of C3 is connected to the fifth switch tube ( Figure 3 The source S (or drain D) of Tsw5) is connected to the ground level;

[0062] The lossless recharging circuit module ( Figure 3 6), including the source follower ( Figure 3 Tsf), the first switch tube ( Figure 3 Tsw1), the second switch tube ( Figure 3 Tsw2), the third switch tube ( Figure 3 Tsw3), the fourth switch tube ( Figure 3 Tsw4), the sixth switch tube ( Figure 3 Tsw6), the second capacitor ( Figure 3 C2), the first resistor ( Figure 3 R1) or constant current source circuit; the source follower ( Figure 3 The drain D of Tsf is connected to the power supply voltage ( Figure 3 Vdd), its gate G is connected to the node J2 ( Figure 3 J2), whose source S is connected to node J3 ( Figure 3 J3); the first switch tube ( Figure 3 The drain D (or source S) of Tsw1 is connected to the node J1 ( Figure 3 J1), whose source S (or drain D) is connected to the node J2 ( Figure 3 J2), by connecting the first switching signal ( Figure 3 SW1) to control its conduction and cutoff; the second switch tube ( Figure 3 The drain D (or source S) of Tsw2 is connected to the node J5 ( Figure 3 J5), whose source S (or drain D) is connected to the node J3 ( Figure 3 J3), by connecting the second switch signal ( Figure 3SW2) to control its conduction and cutoff; the third switch tube ( Figure 3 The source S (or drain D) of Tsw3 is connected to the node J1 ( Figure 3 J1), whose drain D (or source S) is connected to the node J5 ( Figure 3 J5), by connecting its gate to the third switch signal ( Figure 3 SW3) to control its conduction and cutoff; the fourth switch tube ( Figure 3 The source S (or drain D) of Tsw4 is connected to the node J4 ( Figure 3 J4), whose drain D (or source S) is connected to the node J3 ( Figure 3 J3), by connecting its gate to the fourth switch signal ( Figure 3 SW4) to control its conduction and cutoff; the sixth switch tube ( Figure 3 The drain D (or source S) of Tsw6 is connected to the first resistor ( Figure 3 One end of R1, its source S (or drain D) is connected to the ground level, and the sixth switch signal ( Figure 3 SW6) to control its conduction and cutoff; the second capacitor ( Figure 3 One end of C2 is connected to the node J2 ( Figure 3 The other end is connected to the node J5 ( Figure 3 J5); the first resistor ( Figure 3 One end of R1 is connected to the node J3 ( Figure 3 J3), the other end of which is connected to the sixth switch tube ( Figure 3 The drain D (or source S) of TsW6); the lossless recharging module ( Figure 3 6) control signal ( Figure 3 50) by SW1( Figure 3 SW1), SW2( Figure 3 SW2), SW3( Figure 3 SW3), SW4( Figure 3 SW4) and SW6( Figure 3 SW6) to control the opening and closing of each switch tube as needed;

[0063] The output module ( Figure 3 7), including the row gate tube ( Figure 3 The row gate tube ( Figure 3 The drain D (or source S) of Tsel is connected to the node J3 ( Figure 3 J3), whose source S (or drain D) is connected to the column output bus ( Figure 3ColOutput, 8), by connecting its gate to the row selection control signal ( Figure 3 SEL, 40) to control its conduction and cutoff.

[0064] like Figure 4 As shown, it is a flowchart of the working stages of the implementation method of the image sensor pixel circuit in two modes in Example 1. After a frame of exposure begins, the exposure work of the image sensor pixel circuit is based on the external mode control signal ( Figure 3 and Figure 4 60) to select the conventional exposure mode or the intermittent exposure mode; when the intermittent exposure mode is selected, first go through stage A1 ( Figure 4 A1) is the third capacitor for reset and storage ( Figure 3 C3), then through stage A2 ( Figure 4 A2) is the second capacitor ( Figure 3 C2) samples VGS, and then waits until the pulse reflected light echo signal to be received arrives, first passing through stage A3 ( Figure 4 A3) is the reverse charge and lasts for the set time corresponding to this stage, and then passes through stage A4 ( Figure 4 A4) is intermittent exposure and lasts for the time set for this stage, and then passes through stage A5 ( Figure 4 A5) is the first transmission and storage capacitor ( Figure 3 C1), then through stage A6 ( Figure 4 A6) is to turn off all switch tubes, and then determine whether the intermittent exposure in one frame is over? If it is over, enter stage A7 ( Figure 4 A7) is the waiting column output bus ( Figure 3 ColOutput) reads the third capacitor ( Figure 3 C3), and then enters stage A8 ( Figure 4 A8) is the waiting column output bus ( Figure 3 ColOutput) reads the first capacitance ( Figure 3 If not finished, return to stage A2 ( Figure 4 A2); when the conventional exposure mode is selected, first enter stage A11 ( Figure 4 A11) is the third capacitor for reset and storage ( Figure 3 C3), and then enters stage A12 ( Figure 4 A12) is continuous exposure and lasts for the set time corresponding to this stage, and then enters stage A13 ( Figure 4 A13) is the first transmission and storage capacitor ( Figure 3 C1), and then enters stage A14 ( Figure 4 A14) is the waiting column output bus ( Figure 3ColOutput) reads the third capacitor ( Figure 3 C3), and then enters stage A15 ( Figure 4 A15) is the waiting column output bus ( Figure 3 ColOutput) reads the first capacitance ( Figure 3 C1); Figure 4 The specific work sequence of each stage is shown in Figure 5 and Figure 6 The timing diagram of the corresponding stages is shown. The time required to be set in each stage is automatically output to the required module by the image processing circuit according to the detection of the brightness and distance of the image under the setting of the software. The image processing circuit can be included in the image sensor chip or independent of the image sensor chip. The image processing circuit can be divided into multiple modules as needed and placed in the image sensor chip or independent of the image sensor chip.

[0065] like Figure 5 As shown, when the image sensor pixel circuit selects the intermittent exposure mode, the interval exposure timing generation circuit inside the image sensor chip outputs control signals to each pixel in a certain timing to realize intermittent exposure; the working timing of each pixel circuit of the image sensor includes nine Figure 3 Corresponding control signal: reset control signal ( Figure 3 and Figure 5 RST), transmission control signal ( Figure 3 and Figure 5 TX), the first switch signal ( Figure 3 and Figure 5 SW1), the second switch signal ( Figure 3 and Figure 5 SW2), the third switch signal ( Figure 3 and Figure 5 SW3), the fourth switch signal ( Figure 3 and Figure 5 SW4), reset storage control signal ( Figure 3 and Figure 5 SW5), the sixth switch signal ( Figure 3 and Figure 5 SW6), row selection control signal ( Figure 3 and Figure 5 SEL);

[0066] Phase A1 Figure 4 and Figure 5 A1): the reset tube ( Figure 3 Trst), the transmission tube ( Figure 3 Ttx), the first switch tube ( Figure 3 Tsw1) and the fifth switch tube ( Figure 3 Tsw5) is turned on, while the other tubes are turned off, the photosensitive diode ( Figure 3 D1), the first capacitor ( Figure 3 C1) and the third capacitor ( Figure 3 C3) is reset, and the reset level is stored in the third capacitor ( Figure 3 C3) storage;

[0067] Phase A2 Figure 4 and Figure 5 A2): the reset tube ( Figure 3 Trst), the second switch tube ( Figure 3 Tsw2) and the sixth switch tube ( Figure 3 Tsw6) is turned on, while the other tubes are turned off, the source follower ( Figure 3 The voltage difference (VGS) between the gate G and the source S of Tsf) is stored in the second capacitor ( Figure 3 C2);

[0068] Stage A3 Figure 4 and Figure 5 A3): Wait until the pulse reflected light echo signal to be received reaches the image sensor, start the charge backflow work and continue for the set time corresponding to this stage: the third switch tube ( Figure 3 Tsw3), the fourth switch tube ( Figure 3 Tsw4) and the sixth switch tube ( Figure 3 Tsw6) is turned on and lasts for the set time corresponding to this stage, while the other tubes are turned off, and the first capacitor ( Figure 3 The second capacitor (C1) is connected in series Figure 3 After C2) the voltage is sent to the source follower ( Figure 3 Tsf) of the gate G, through the source follower ( Figure 3 The source S of Tsf) is backflowed to the photosensitive diode ( Figure 3 D1), since the second capacitor ( Figure 3 C2) level with the source follower ( Figure 3 The voltage difference (VGS) between the gate G and the source S of Tsf) is the same, so the voltage stored in the first capacitor ( Figure 3 The charge of C1) is then sent back to the photodiode ( Figure 3 D1);

[0069] Stage A4 Figure 4 and Figure 5 A4): All tubes are disconnected and last for the set time corresponding to this stage. The photosensitive diode ( Figure 3 The charge of D1) has been set to the first capacitor ( Figure 3 The charge of C1) is accumulated, and the A4 stage starts to receive external exposure light during the gap exposure period on this basis;

[0070] Stage A5 Figure 4 and Figure 5 A5): the transmission tube ( Figure 3 Tsf) is turned on, while the other tubes are turned off, the photosensitive diode ( Figure 3 The accumulated light-sensing level signal of D1 is transferred to the first capacitor ( Figure 3 C1) storage;

[0071] Stage A6 Figure 4 and Figure 5 A6): That is, all tubes are disconnected. At this stage, the photosensitive diode ( Figure 3 The exposure signal received by D1) is not adopted and is not stored in the first capacitor ( Figure 3 During this period, the gap exposure timing generation circuit in the image sensor chip determines whether the gap exposure in one frame is completed. If it is completed, it enters stage A7 ( Figure 4 and Figure 5 A7); if not finished, return to stage A2 ( Figure 4 and Figure 5 A2);

[0072] Stage A7 Figure 4 and Figure 5 A7): Waiting for the fifth switch tube ( Figure 3 Tsw5) and the row gate tube ( Figure 3 Tsel) is turned on, the sixth switch tube ( Figure 3 Tsw6) is turned on or off as needed, while other tubes are turned off, the column output bus ( Figure 3 ColOutput) reads the third capacitor ( Figure 3 C3) reset level signal;

[0073] Stage A8 Figure 4 and Figure 5 A8): When needed, the first switch tube ( Figure 3 Tsw1) and the row gate tube ( Figure 3 Tse1) is turned on, the sixth switch tube ( Figure 3 Tsw6) is turned on or off as needed, while other tubes are turned off, the column output bus ( Figure 3 ColOutput) reads the first capacitance ( Figure 3The light-sensing level signal of C1) is the first capacitor ( Figure 3 C1) and the third capacitor ( Figure 3 The charge difference of C3), that is, the difference between the light-sensitive level signal and the reset level signal, is the image data signal of the image sensor pixel circuit;

[0074] In Example 1 of the present invention, taking the cycle time of one frame as 33.3 ms as an example, when working in the intermittent exposure mode, since each intermittent exposure repetition cycle consists of the stage A2 ( Figure 5 A2), the stage A3 ( Figure 5 A3), said stage A4 ( Figure 5 A4), said stage A5 ( Figure 5 A5) and the stage A6 ( Figure 5 A6) of the composition, when a gap exposure repetition cycle is set to 1us, if the stage A2 ( Figure 5 A2), the stage A3 ( Figure 5 A3), said stage A4 ( Figure 5 A4) and the stage A5 ( Figure 5 The interval time of stage A5) is 10ns, then the stage A6 ( Figure 5 The maximum interval time of A6) is 1us-10ns*4=960ns; usually the phase A2 ( Figure 5 A2) and A3 ( Figure 5 There is a time interval between A3), not close together, so the interval of A6 is less than 960ns; at the same time, the phase A1 ( Figure 5 A1), said stage A7 ( Figure 5 A7) and the stage A8 ( Figure 5 The interval time of A8) can also be set to 10ns; when the total exposure time in one frame is about 10ms, 10ms / 1us=10000 interval exposure cycles are allowed in the exposure time of one frame, that is, the number of interval exposures allowed is up to 10000 times.

[0075] In this embodiment 1, the lossless recharging circuit module ( Figure 3 The calibration process of the re-injection error of 6) is as follows: Assume a special calibration frame, the first step is to execute the stage A1 ( Figure 4 and Figure 5 A1), the second step is to execute the stage A2 ( Figure 4 and Figure 5 A2), the third step is to perform the first capacitor ( Figure 3 The light-sensitive level signal stored in C1) is fed back through the lossless recharging circuit module ( Figure 3 6) to the photosensitive module ( Figure 3 1), the fourth step is to perform the stage A5 ( Figure 4 and Figure 5 A5), the photosensitive module ( Figure 3 1) sends the light-sensitivity level signal to the storage module ( Figure 3 3) in which the first capacitor ( Figure 3 The fifth step is to repeat the third and fourth steps according to the set number of times, and the sixth step is to execute the stage A7 ( Figure 4 and Figure 5 A7), the seventh step executes the stage A8 ( Figure 4 and Figure 5 A8), it can be obtained that after the set number of repetitions, the lossless recharge module ( Figure 1 6) The error caused by

[0076] like Figure 6 As shown, when the image sensor pixel circuit selects the conventional exposure mode, the first capacitor ( Figure 3 C1) is used to store the light sensitivity level signal obtained by exposure, and the third capacitor ( Figure 3 C3) is used to store the reset level; when used as a rolling image sensor, the first capacitor ( Figure 3 C1) can be used to store the light sensitivity level signal obtained by long-term exposure, and the third capacitor ( Figure 3 C3) is used not only to store the reset level, but also to store the photosensitive level signal obtained by short-time exposure, so as to collect the photosensitive level signals corresponding to two different exposure times within one continuous exposure time, thereby improving the high dynamic range of the image sensor chip;

[0077] When the image sensor pixel circuit selects the conventional exposure mode, the working timing of each pixel circuit of the image sensor includes six control signals: a reset control signal ( Figure 6 RST), transmission control signal ( Figure 6 TX), the first switch signal ( Figure 6 SW1), reset storage control signal ( Figure 6 SW5), the sixth switch signal ( Figure 6 SW6), row selection control signal ( Figure 6 SEL);

[0078] Stage A11( Figure 4 and Figure 6 A11): the reset tube ( Figure 3 Trst), the transmission tube ( Figure 3 Ttx), the first switch tube ( Figure 3Tsw1) and the fifth switch tube ( Figure 3 Tsw5) is turned on, while the other tubes are turned off, the photosensitive diode ( Figure 3 D1), the first capacitor ( Figure 3 C1) and the third capacitor ( Figure 3 C3) is reset, and the reset level is stored in the third capacitor ( Figure 3 C3) storage;

[0079] Stage A12 ( Figure 4 and Figure 6 A12): All tubes are disconnected, and the photosensitive diode ( Figure 3 D1) receives external exposure light and accumulates photogenerated charges for a set time period in this stage;

[0080] Stage A13 ( Figure 4 and Figure 6 A13): the transmission tube ( Figure 3 Tsel) is turned on, while the other tubes are turned off, the photosensitive diode ( Figure 3 The light-sensitivity level signal obtained after exposure of D1) is sent to the first capacitor ( Figure 3 C1) storage;

[0081] Stage A14 ( Figure 4 and Figure 6 A14): Waiting for the fifth switch tube ( Figure 3 Tsw5) and the row gate tube ( Figure 3 Tsel) is turned on, the sixth switch tube ( Figure 3 Tsw6) is turned on as needed, while other tubes are turned off, the column output bus ( Figure 3 ColOutput) reads the third capacitor ( Figure 3 C3) reset level signal;

[0082] Stage A15( Figure 4 and Figure 6 A15): Waiting for the first switch tube when needed ( Figure 3 Tsw1) and the row gate tube ( Figure 3 The Tsel of the column is turned on, the sixth switch tube is optional, and the other tubes are disconnected, and the column output bus ( Figure 3 ColOutput) reads the first capacitance ( Figure 3 The light-sensing level signal of C1) is the first capacitor ( Figure 3 C1) and the third capacitor ( Figure 3 The charge difference of C3), that is, the difference between the photosensitive level signal and the reset level signal, is the image data signal of the photosensitive pixel unit;

[0083] In Example 1 of the present invention, taking the cycle time of one frame as 33.3 ms as an example, when working in the conventional exposure mode, the exposure time in one frame consists of one conventional exposure cycle. If the stage A11 ( Figure 6 A11), the stage A13 ( Figure 6 A13), the stage A14 ( Figure 6 A14) and the stage A15 ( Figure 6 The interval time of A15) is set to 10ns, then the phase A12 ( Figure 6 The interval time of A12) is the time after deducting 40ns from the exposure time in one frame, and the exposure time in one frame is approximately between 0.1ms and 30ms depending on the influence of ambient light.

[0084] like Figure 7 , Figure 8 , Fig. 9 , Fig.10 The figure shows a pixel circuit structure and implementation method of a non-continuous exposure image sensor provided by Example 2 of the present invention:

[0085] like Figure 7 As shown, when the storage module ( Figure 7 3) in which the first capacitor is connected to the photosensitive module ( Figure 7 When the light-sensing level signal in D1) has a greater impact, the original first capacitor is removed and the storage capacitor is the fourth capacitor ( Figure 7 C4); In Example 2, the components of the image sensor pixel circuit include: a photosensitive diode, twelve switch transistors, three storage capacitors and a current limiting resistor or a constant current source circuit, that is: the photosensitive diode ( Figure 7 D1), transmission tube ( Figure 7 Ttx), reset tube ( Figure 7 Trst), source follower ( Figure 7 Tsf), row gate tube ( Figure 7 Tsel), the first switch tube ( Figure 7 Tsw1), the second switch tube ( Figure 7 Tsw2), the third switch tube ( Figure 7 Tsw3), the fourth switch tube ( Figure 7 Tsw4), the fifth switch tube ( Figure 7 Tsw5), the sixth switch tube ( Figure 7 Tsw6), the seventh switch tube ( Figure 7 Tsw7), the eighth switch tube ( Figure 7 Tsw8), the second capacitor is the compensation capacitor ( Figure 7 C2), the third capacitor ( Figure 7 C3), the fourth capacitor ( Figure 7 C4), the first resistor ( Figure 7 R1); and the drain D ( Figure 7 D), source S( Figure 7 S), gate G( Figure 7 G); Circuit connection points include: Node J1 ( Figure 7 Node J1), node J2 ( Figure 7 Node J2), node J3 ( Figure 7 Node J3), node J4 ( Figure 7 Node J4), node J5 ( Figure 7 Node J5), node J6 ( Figure 7 J6); Output bus includes: Column output bus ( Figure 7 ColOutput); control signals include: TX ( Figure 7 10)-transmission control signal, RST ( Figure 7 20)-Reset control signal, SW5( Figure 7 30)-Reset storage control signal, SEL ( Figure 7 40)-row selection control signal, lossless control signal ( Figure 7 50) includes SW1-first switch signal ( Figure 7 SW1), SW2- second switch signal ( Figure 7 SW2), SW3- the third switch signal ( Figure 7 SW3), SW4- the fourth switch signal ( Figure 7 SW4) and SW6-sixth switch signal ( Figure 7 SW6), and external mode control signal ( Figure 7 of 60);

[0086] The photosensitive module ( Figure 7 1), comprising the photodiode ( Figure 7 D1); the photodiode ( Figure 7 The negative terminal of D1 is connected to the node J4 ( Figure 7 J4), its positive terminal is connected to the ground level;

[0087] The transmission module ( Figure 7 2), comprising the transmission tube ( Figure 7 Ttx); the transmission tube ( Figure 7 The drain D (or source S) of Ttx is connected to the node J4 ( Figure 7 J4), whose source S (or drain D) is connected to the node J1 ( Figure 7 J1), by connecting its gate to the transmission control signal ( Figure 7 TX, 10) to control its conduction and cutoff;

[0088] The storage module ( Figure 7 3) includes the fourth capacitor ( Figure 7 C4), the seventh switch tube ( Figure 7 Tsw7), the eighth switch tube ( Figure 7 Tsw8); the seventh switch tube ( Figure 7 The drain D (or source S) of Tsw7 is connected to the node J6 ( Figure 7 J6), whose source S (or drain D) is connected to the node J1 ( Figure 7 J1), by connecting its gate to the seventh switch signal ( Figure 7 SW7) to control its conduction and cutoff; the eighth switch tube ( Figure 7 The drain D (or source S) of Tsw8 is connected to the node J3 ( Figure 7 J3), whose source S (or drain D) is connected to the node J6 ( Figure 7 J6), by connecting its gate to the eighth switch signal ( Figure 7 SW8) to control its conduction and cutoff; the fourth capacitor ( Figure 7 One end of C4 is connected to the node J6 ( Figure 7 The other end of J6 is connected to the ground level;

[0089] When storing the signal, the transmission module ( Figure 7 2) first transmit the light-sensing level signal to the lossless recharging module ( Figure 7 6), through the lossless recharging module ( Figure 7 6) the third switch tube ( Figure 7 Tsw3), the second capacitor ( Figure 7 C2), the source follower ( Figure 7 Tsf) and then sent out, and then through the eighth switch tube ( Figure 7 Tsw8) is sent to the fourth capacitor ( Figure 7 C4) to store the lossless recharging module ( Figure 7 6) for the storage module ( Figure 7 3) for lossless driving; and when it is necessary to read the fourth capacitor ( Figure 7 When storing data in C4), the first path is through the fourth capacitor ( Figure 7 C4), the seventh switch tube ( Figure 7 Tsw7), and then through the lossless recharging module ( Figure 7 6) the third switch tube ( Figure 7 Tsw3), the second capacitor ( Figure 7 C2), the source follower ( Figure 7Tsf) is output to the output module ( Figure 7 7), the second path is through the fourth capacitor ( Figure 7 C4), the seventh switch tube ( Figure 7 Tsw7), the first switch tube ( Figure 7 Tsw1), the source follower ( Figure 7 Tsf) is output to the output module ( Figure 7 7), regardless of the first or second path, the sixth switch tube ( Figure 7 Tsw6) is turned on or off as needed; SW7 ( Figure 7 SW7) and SW8( Figure 7 SW8) constitutes the storage module ( Figure 7 3) control signal ( Figure 7 70), to control opening and closing as needed;

[0090] The reset module ( Figure 7 4), including the reset tube ( Figure 7 Trst); the reset tube ( Figure 7 The drain D (or source S) of Trst is connected to the power supply voltage 1 ( Figure 7 Vdd1), its source S (or drain D) is connected to the node J2 ( Figure 7 J2), by connecting the reset control signal ( Figure 7 RST, 20) to control its conduction and cutoff;

[0091] The reset storage module ( Figure 7 5), including the fifth switch tube ( Figure 7 Tsw5), the third capacitor ( Figure 7 C3); the fifth switch tube ( Figure 7 The drain D (or source S) of Tsw5 is connected to the node J2 ( Figure 7 J2), whose source S (or drain D) is connected to the third capacitor ( Figure 7 One end of C3) is connected to the gate of the fifth switch signal ( Figure 7 SW5, 30) to control its conduction and cutoff; the third capacitor ( Figure 7 One end of C3 is connected to the fifth switch tube ( Figure 7 The source S (or drain D) of Tsw5) is connected to the ground level;

[0092] The lossless recharging circuit module ( Figure 7 6), including the source follower ( Figure 7 Tsf), the first switch tube ( Figure 7Tsw1), the second switch tube ( Figure 7 Tsw2), the third switch tube ( Figure 7 Tsw3), the fourth switch tube ( Figure 7 Tsw4), the sixth switch tube ( Figure 7 Tsw6), the second capacitor ( Figure 7 C2), the first resistor ( Figure 7 R1); the source follower ( Figure 7 The drain D of Tsf is connected to the power supply voltage ( Figure 7 Vdd), its gate G is connected to the node J2 ( Figure 7 J2), whose source S is connected to the node J3 ( Figure 7 J3); the first switch tube ( Figure 7 The drain D (or source S) of Tsw1 is connected to the node J1 ( Figure 7 J1), whose source S (or drain D) is connected to the node J2 ( Figure 7 J2), by connecting the first switching signal ( Figure 7 SW1) to control its conduction and cutoff; the second switch tube ( Figure 7 The drain D (or source S) of Tsw2 is connected to the node J5 ( Figure 7 J5), whose source S (or drain D) is connected to the node J3 ( Figure 7 J3), by connecting the second switch signal ( Figure 7 SW2) to control its conduction and cutoff; the third switch tube ( Figure 7 The source S (or drain D) of Tsw3 is connected to the node J1 ( Figure 7 J1), whose drain D (or source S) is connected to the node J5 ( Figure 7 J5), by connecting its gate to the third switch signal ( Figure 7 SW3) to control its conduction and cutoff; the fourth switch tube ( Figure 7 The source S (or drain D) of Tsw4 is connected to the node J4 ( Figure 7 J4), whose drain D (or source S) is connected to the node J3 ( Figure 7 J3), by connecting its gate to the fourth switch signal ( Figure 7 SW4) to control its conduction and cutoff; the sixth switch tube ( Figure 7 The drain D (or source S) of Tsw6 is connected to the first resistor ( Figure 7 One end of R1, its source S (or drain D) is connected to the ground level, and the sixth switch signal ( Figure 7 SW6) to control its conduction and cutoff; the second capacitor ( Figure 7 One end of C2 is connected to the node J2 ( Figure 7 The other end is connected to the node J5 ( Figure 7 J5); the first resistor ( Figure 7 One end of R1 is connected to the node J3 ( Figure 7 J3), the other end of which is connected to the sixth switch tube ( Figure 7 Tsw6) of the drain D (or source S); SW1 ( Figure 7 SW1), SW2( Figure 7 SW2), SW3( Figure 7 SW3), SW4( Figure 7 SW4) and SW6( Figure 7 SW6) constitutes the lossless recharging circuit ( Figure 7 6) Module control signal ( Figure 7 50), to control the opening and closing of each switch tube as needed;

[0093] The output module ( Figure 7 7), including the row gate tube ( Figure 7 The row gate tube ( Figure 7 The drain D (or source S) of Tsel is connected to the node 3 ( Figure 7 J3), whose source S (or drain D) is connected to the column output bus ( Figure 7 ColOutput, 8), by connecting its gate to the row selection signal ( Figure 7 SEL, 40) to control its conduction and cutoff.

[0094] like Figure 8 As shown, after a frame of exposure begins, the exposure operation of the image sensor pixel circuit is controlled according to an external mode control signal ( Figure 7 and Figure 8 60) to select the conventional exposure mode or the intermittent exposure mode; when the intermittent exposure mode is selected, first go through stage B1 ( Figure 8 and Fig. 9 B1) is the third capacitor for reset and storage ( Figure 7 C3), then through stage B2 ( Figure 8 and Fig. 9 B2) is the second capacitor ( Figure 7 C2) samples VGS, and then waits until the pulse reflected light echo signal to be received reaches the image sensor, first passing through stage B3 ( Figure 8 and Fig. 9 B3) is the reverse charge and lasts for the set time corresponding to this stage, and then passes through stage B4 ( Figure 8 and Fig. 9B4) is intermittent exposure and lasts for the set time corresponding to this stage, and then passes through stage B5 ( Figure 8 and Fig. 9 B5) is the fourth capacitor for transmission and storage ( Figure 7 C4), then through stage B6 ( Figure 8 and Fig. 9 B6) is to turn off all switch tubes, and then determine whether the intermittent exposure in one frame is over? If it is over, enter stage B7 ( Figure 8 and Fig. 9 B7) is the waiting column output bus ( Figure 7 Co1Output) reads the third capacitor ( Figure 7 C3), and then enters stage B8 ( Figure 8 and Fig. 9 B8) is the waiting column output bus ( Figure 7 ColOutput) reads the fourth capacitor ( Figure 7 C4); if not finished, return to stage B2 ( Figure 8 and Fig. 9 When the conventional exposure mode is selected, the first step is to enter stage B11 ( Figure 8 and Fig.10 B11) is the third capacitor for reset and storage ( Figure 7 C3), and then enters stage B12 ( Figure 8 and Fig.10 B12) is continuous exposure and lasts for the time set in this stage, and then enters stage B13 ( Figure 8 and Fig.10 B13) is the fourth capacitor for transmission and storage ( Figure 7 C4), then enters stage B14 ( Figure 8 and Fig.10 B14) is the waiting column output bus ( Figure 7 ColOutput) reads the third capacitor ( Figure 7 C3), then enters stage B15 ( Figure 8 and Fig.10 B15) is the waiting column output bus ( Figure 7 ColOutput) reads the fourth capacitor ( Figure 7 C4); Figure 8 The specific work sequence of each stage is shown in Fig. 9 and Fig.10 The corresponding stages are shown in the timing diagram.

[0095] like Fig. 9As shown in FIG. 1 , when the image sensor pixel circuit selects the intermittent exposure mode, the interval exposure timing generation circuit inside the image sensor chip outputs control signals to each pixel in a certain timing to realize intermittent exposure; the working timing of each pixel circuit of the image sensor includes eleven control signals: reset control signal ( Figure 7 and Fig. 9 RST), transmission control signal ( Figure 7 and Fig. 9 TX), the first switch signal ( Figure 7 and Fig. 9 SW1), the second switch signal ( Figure 7 and Fig. 9 SW2), the third switch signal ( Figure 7 and Fig. 9 SW3), the fourth switch signal ( Figure 7 and Fig. 9 SW4), reset storage control signal ( Figure 7 and Fig. 9 SW5), the sixth switch signal ( Figure 7 and Fig. 9 SW6), the seventh switch signal ( Figure 7 and Fig. 9 SW7), the eighth switch signal ( Figure 7 and Fig. 9 SW8), row selection control signal ( Figure 7 and Fig. 9 SEL);

[0096] Stage B1 Figure 8 and Fig. 9 B1): the reset tube ( Figure 7 Trst), the transmission tube ( Figure 7 Ttx), the first switch tube ( Figure 7 Tsw1), the fifth switch tube ( Figure 7 Tsw5) and the seventh switch tube ( Figure 7 Tsw7) is turned on, while the other tubes are turned off, the photosensitive diode ( Figure 7 D1), the first capacitor ( Figure 7 C1), the fourth capacitor ( Figure 7 C4) and the third capacitor ( Figure 7 C3) for reset;

[0097] Stage B2 Figure 8 and Fig. 9 B2): the reset tube ( Figure 7 Trst), the second switch tube ( Figure 7 Tsw2) and the sixth switch tube ( Figure 7Tsw6) is turned on, while the other tubes are turned off, the source follower ( Figure 7 The voltage difference (VGS) between the gate G and the source S of Tsf) is stored in the second capacitor ( Figure 7 C2);

[0098] Stage B3 Figure 8 and Fig. 9 B3): Wait until the pulse reflected light echo signal to be received reaches the image sensor, start the charge backflow work and continue for the set time corresponding to this stage: the third switch tube ( Figure 7 Tsw3), the fourth switch tube ( Figure 7 Tsw4), the seventh switch tube ( Figure 7 Tsw7) and the sixth switch tube ( Figure 7 Tsw6) is turned on and lasts for the set time corresponding to this stage, while other transistors are turned off, and the fourth capacitor ( Figure 7 The second capacitor (C4) is connected in series Figure 7 After C2) the voltage is sent to the source follower ( Figure 7 Tsf) of the gate G, through the source follower ( Figure 7 The source S of Tsf) is backflowed to the photosensitive diode ( Figure 7 D1), since the second capacitor ( Figure 7 C2) level with the source follower ( Figure 7 The voltage difference (VGS) between the gate G and the source S of Tsf) is the same, so the voltage stored in the fourth capacitor ( Figure 7 The charge of C4 is then sent back to the photodiode ( Figure 7 D1);

[0099] Stage B4 Figure 8 and Fig. 9 B4): All tubes are disconnected and last for the set time corresponding to this stage. The photosensitive diode ( Figure 7 The light-sensing level signal of D1 will be at the fourth capacitor ( Figure 7 Starting to accumulate and receive external exposure light during the intermittent exposure period based on the photosensitivity level signal of C4);

[0100] Stage B5 Figure 8 and Fig. 9 B5): the transmission tube ( Figure 7 The third switch tube ( Figure 7 Tsw3) is turned on, the source follower ( Figure 7 Tsf) works, the sixth switch tube ( Figure 7Tsw6) is turned on, the eighth switch tube ( Figure 7 Tsw8) is turned on, while the other tubes are turned off, the photosensitive diode ( Figure 7 The accumulated light-sensing level signal of D1) is transmitted through the lossless recharging circuit module ( Figure 7 6) is transferred to the fourth capacitor ( Figure 7 C4) storage;

[0101] Stage B6 Figure 8 and Fig. 9 B6): That is, all tubes are disconnected, then the photosensitive diode ( Figure 7 The exposure signal received by D1) is discarded and not stored in the fourth capacitor ( Figure 7 During this period, the gap exposure timing generation circuit in the image sensor chip determines whether the gap exposure in one frame is completed. If it is completed, it enters stage B7 ( Figure 8 and Fig. 9 B7); if not finished, return to stage B2 ( Figure 8 and Fig. 9 B2);

[0102] Stage B7 Figure 8 and Fig. 9 B7): When the row strobe control signal ( Figure 7 When the SEL and 40) are in the state of selecting the current row, the fifth switch tube ( Figure 7 Tsw5) is turned on, the sixth switch tube ( Figure 7 Tsw6) is turned on as needed and the row gate tube ( Figure 7 Tsel) is turned on, while the other tubes are turned off, and the column output bus ( Figure 7 ColOutput) reads the third capacitor ( Figure 7 C3) reset level signal;

[0103] Stage B8 Figure 8 and Fig. 9 B8): When the row strobe control signal ( Figure 7 When the SEL and 40) are in the state of selecting the current row, the third switch tube ( Figure 7 Tsw3) is turned on, the seventh switch tube ( Figure 7 Tsw7) is turned on, the sixth switch tube ( Figure 7 Tsw6) is turned on as needed and the row gate tube ( Figure 7 The Tse1 of the capacitor is turned on, while the other transistors are turned off. When necessary, the column output bus (ColOutput) reads the fourth capacitor ( Figure 7 The fourth capacitor ( Figure 7C4) and the third capacitor ( Figure 7 The charge difference of C3), that is, the difference between the photosensitivity level signal and the reset level signal, is the image data signal of the image sensor pixel circuit.

[0104] In Example 2 of the present invention, taking the cycle time of one frame as 33.3 ms as an example, when working in the intermittent exposure mode, since each intermittent exposure repetition cycle consists of the stage B2 ( Fig. 9 B2), the stage B3 ( Fig. 9 B3), the stage B4 ( Fig. 9 B4), the stage B5 ( Fig. 9 B5) and B6 ( Fig. 9 When a gap exposure repetition period is set to 1us, if the stage B2 ( Fig. 9 B2), the stage B3 ( Fig. 9 B3), the stage B4 ( Fig. 9 B4) and the stage B5 ( Fig. 9 The interval time of stage B5) is 10ns, then the stage B6 ( Fig. 9 The maximum interval time of B6) is 1us-10ns*4=960ns; usually the phase B2 ( Fig. 9 B2) and B3 ( Fig. 9 There is a time interval between B3), which is not close together, so the interval of B6 is less than 960ns; at the same time, the phase B1 ( Fig. 9 B1), B7 ( Fig. 9 B7) and the stage B8 ( Fig. 9 The interval time of B8) can also be set to 10ns; when the total exposure time in one frame is about 10ms, 10ms / 1us=10000 intermittent exposure cycles are allowed in the exposure time of one frame, that is, the number of intermittent exposures allowed is up to 10000 times.

[0105] In the second embodiment of the present invention, the lossless recharging circuit module ( Figure 7 The calibration process of the re-injection error of 6) is as follows: Assume a special calibration frame, the first step is to execute the stage B1 ( Figure 8 and Fig. 9 B1), the second step is to execute the stage B2 ( Figure 8 and Fig. 9 B2), the third step is to perform the fourth capacitor ( Figure 7 The light-sensitive level signal stored in C4) is fed back through the lossless recharging circuit module ( Figure 7 6) back to the photosensitive module ( Figure 7 1), the fourth step is to perform the stage B5 ( Figure 8 and Fig. 9 B5), the photosensitive module ( Figure 7 1) sends the light-sensitivity level signal to the storage module ( Figure 7 3) in the fourth capacitor ( Figure 7 The fifth step is to repeat the third and fourth steps according to the set number of times, and the sixth step is to execute the stage B7 ( Figure 8 and Fig. 9 The seventh step is to execute the stage B8 ( Figure 8 and Fig. 9 B8), it can be obtained that after the set number of repetitions, the lossless recharge module ( Figure 7 6) The error caused by

[0106] like Fig.10 As shown, when the image sensor pixel circuit selects the conventional exposure mode, the working timing of each pixel circuit of the image sensor includes eight control signals: a reset control signal ( Figure 7 and Fig.10 RST), transmission control signal ( Figure 7 and Fig.10 TX), the first switch signal ( Figure 7 and Fig.10 SW1), reset storage control signal ( Figure 7 and Fig.10 SW5), the sixth switch signal ( Figure 7 and Fig.10 SW6), the seventh switch signal ( Figure 7 and Fig.10 SW7), the eighth switch signal ( Figure 7 and Fig.10 SW8), row selection control signal ( Figure 7 and Fig.10 SEL);

[0107] Stage B11 Figure 8 and Fig.10 B11): the reset tube ( Figure 7 Trst), the transmission tube ( Figure 7 Ttx), the first switch tube ( Figure 7 Tsw1), and the fifth switch tube ( Figure 7 Tsw5) and the seventh switch tube ( Figure 7 Tsw7) is turned on, while the other tubes are turned off, the photosensitive diode ( Figure 7 D1), the fourth capacitor ( Figure 7 C4) and the third capacitor ( Figure 7 C3) reset;

[0108] Stage B12 Figure 8 and Fig.10 B12): All tubes are disconnected and last for the set time corresponding to this stage, and the photosensitive diode ( Figure 7 D1) receives external exposure light and accumulates photogenerated charges;

[0109] Stage B13 Figure 8 and Fig.10 B13): the transmission pipe ( Figure 7 Ttx), the third switch tube ( Figure 7 Tsw3), the sixth switch tube ( Figure 7 Tsw6), the eighth switch tube ( Figure 7 Tsw8) is turned on, while the other tubes are turned off, the photosensitive diode ( Figure 7 The light-sensitivity level signal accumulated after exposure of D1) is passed through the lossless recharge circuit module ( Figure 7 6) is sent to the fourth capacitor ( Figure 7 C4) storage;

[0110] Stage B14 Figure 8 and Fig.10 B14): When the row strobe control signal ( Figure 7 When the SEL, 40) of the present row is selected, the fifth switch tube ( Figure 7 Tsw5) is turned on, the sixth switch tube ( Figure 7 Tsw6) is turned on as needed and the row gate tube ( Figure 7 Tsel) is turned on, while the other tubes are turned off, and the column output bus ( Figure 7 ColOutput) Figure 7 8) read the third capacitor ( Figure 7 C3) reset level signal;

[0111] Stage B15 Figure 8 and Fig.10 B15): When the row strobe control signal ( Figure 7 When the SEL and 40) are in the state of selecting the current row, the third switch tube ( Figure 7 Tsw3) is turned on, the seventh switch tube ( Figure 7 Tsw7) is turned on, the row gate tube ( Figure 7 Tsel) is turned on, the sixth switch tube ( Figure 7 Tsw6) is turned on as needed, while other tubes are turned off, and the column output bus ( Figure 7 ColOutput, 8) reads the fourth capacitor ( Figure 7The fourth capacitor ( Figure 7 C4) and the third capacitor ( Figure 7 The charge difference of C3), that is, the difference between the photosensitive level signal and the reset level signal, is the image data signal of the photosensitive pixel unit;

[0112] In Example 2 of the present invention, taking the cycle time of one frame as 33.3 ms as an example, when working in the conventional exposure mode, the exposure time in one frame consists of one conventional exposure cycle. If the stage B11 ( Fig.10 B11), B13 ( Fig.10 B13), the stage B14 ( Fig.10 B14) and the stage B15 ( Fig.10 The interval time of B15) is set to 10ns, then the phase B12 ( Fig.10 The interval time of B12) is the time after 40ns is deducted from the exposure time in one frame, and the exposure time in one frame is approximately between 0.1ms and 30ms depending on the influence of ambient light.

[0113] The image sensor pixel circuit described in this patent supports the use of pulsed light emitted by an external pulsed light source as an exposure light source, and senses, stores and accumulates intermittent exposure of non-continuous exposure; the image sensor pixel circuit supports intermittent exposure of dozens to tens of thousands of times per frame, realizes the ability to capture enhanced images of environments at different distances, adapts to various weather conditions, and improves image perception performance.

[0114] The above description is only the preferred embodiment of the present invention, and the embodiment is not intended to limit the scope of patent protection of the present invention. Various modifications to the embodiment will be obvious to professionals in the field, and the general principles defined in this article can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown in this article, but should conform to the widest scope consistent with the principles, innovations and novel features disclosed in this article.

Claims

1. A structure of a pixel circuit of an image sensor for non-continuous exposure, characterized in that: The structure of the pixel circuit used in each photosensitive pixel unit of the image sensor chip includes, according to the functions, a photosensitive module, a transmission module, a storage module, a reset module, a reset storage module, a lossless recharging module, and an output module; the photosensitive pixel unit supports the pulse light emitted by an external pulse light source as an exposure light source; the exposure performed by the photosensitive pixel unit corresponding to each pulse light source is an intermittent exposure; The photosensitive module is used for sensing external light and pulse reflected light emitted by an external pulse light source and then reflected from an object to reach the image sensor chip; the reset level of the reset module can be directly input into the photosensitive module for resetting; or input into the photosensitive module through the storage module and the transmission module for resetting; or input into the photosensitive module through the lossless recharge module, the storage module and the transmission module for resetting, at which time the lossless recharge module is in a reset state; the lossless recharge module is connected to the photosensitive module, and when necessary, the lossless recharge module inputs the final accumulated photosensitivity level signal after the last intermittent exposure stored in the storage module into the photosensitive module, at which time the lossless recharge module is in a lossless driving state; the photosensitive module is connected to the transmission module, and when necessary, the photosensitive module outputs the accumulated photosensitivity level signal after each intermittent exposure or the final accumulated photosensitivity level signal to the transmission module; The transmission module is used to transmit the final accumulated light sensitivity level signal stored by the light sensing module to the storage module after an interval exposure or a frame exposure is completed; a transmission control signal is connected to the transmission module to control the opening and closing of the transmission module; when necessary, the transmission module outputs the light sensitivity level signal to the storage module; The storage module is used to store the final accumulated photosensitivity level signal after each intermittent exposure or after one frame of exposure, and the storage medium is a capacitor; There may be more than one storage capacitor for storing the photosensitive level signal in the storage module, which are respectively used for storing the photosensitive level signals of intermittent exposure at different times, and different capacitors have independent electronic switches; when the photosensitive level signal is transmitted from the photosensitive module to the storage module, if the storage capacitor in the storage module has little effect on the photosensitive level signal in the photosensitive module, the transmission module is directly connected to the storage module and can transmit the photosensitive level signal directly to the storage module for storage; when the photosensitive level signal needs to be transmitted from the photosensitive module to the storage module, if the storage capacitor in the storage module has a greater effect on the photosensitive level signal in the photosensitive module, the The transmission module is directly connected to the lossless recharge module, and the storage module is respectively connected to the lossless recharge module and the transmission module via an electronic switch. The transmission module first transmits the photosensitive level signal to the lossless recharge module, and then the lossless recharge module performs lossless driving on the photosensitive level signal and then stores it in the storage module for storage. At this time, the lossless recharge module is in a lossless driving state; when necessary, the storage module recharges the photosensitive level signal to the photosensitive module through the lossless recharge module; when necessary, the storage module outputs the photosensitive level signal to the output module through the lossless recharge module, and at this time, the lossless recharge module is in a lossy driving state or a lossless driving state as required; The reset module is used to reset the photosensitive module, the storage module, the reset storage module and the lossless recharge module during initialization; the reset control signal is connected to the reset module to control the opening and closing of the reset module; there are two ways to connect the reset module to the photosensitive module, one is that the reset module is directly connected to the photosensitive module through an electronic switch, and the reset level is directly transmitted to the photosensitive module by the reset module; second, the reset module is connected to the lossless recharge module, the storage module, and the transmission module through an electronic switch, and the reset level is transmitted to the photosensitive module through the lossless recharge module, the storage module, and the transmission module; the reset module is connected to the storage module, the reset storage module and the lossless recharge module through an electronic switch; when resetting is required, the reset module outputs the reset level to the photosensitive module, the storage module, the reset storage module and the lossless recharge module and performs a reset; The reset storage module is used to store the reset level signal of the photosensitive module during initialization; the reset storage control signal is connected to the reset storage module to control the opening and closing of the reset storage module; when necessary, the reset storage module reads and stores the reset level signal; when necessary, the reset storage module outputs the stored reset level signal to the column output bus through the lossless recharging module and the output module; The lossless recharge module is used to recharge the photosensitive level signal stored in the storage module after the last gap exposure to the photosensitive module without loss before a new gap exposure corresponding to the arrival of a new pulse reflection light, so that the photosensitive module returns to the photosensitive level signal saved after the last gap exposure and starts the accumulation of this new gap exposure. The unnecessary photosensitive level signal collected by the photosensitive module between two gap exposures is cleared; the lossless control signal is connected to the lossless recharge module, and the lossless recharge module opens different switch tubes in the lossless recharge module according to different functional requirements to achieve different functions. The lossless control signal is composed of a group of control signals of different switch tubes that realize different functions; the lossless recharge module includes a reset state, a disconnected state, a lossy drive state, and a lossless drive state; the reset state is used for resetting the initial stage of a frame exposure, or charging the compensation capacitor required for lossless drive; In the disconnected state, the connection switches between the lossless recharge module and other modules are in the disconnected state, which is used for the period when the lossless recharge module does not need to generate a driving signal; in the lossy driving state, the lossless recharge module is in a lossy current enhancement driving state, which can be used for output driving at the end of a frame of exposure when necessary; in the lossless driving state, the lossless recharge module includes a current enhancement driving circuit and a compensation circuit for compensating for the level loss caused by the current enhancement driving circuit, and can restore the photosensitive level signal stored in the storage module after the last intermittent exposure to the photosensitive module without loss, or be used for output driving at the end of a frame of exposure; whether the lossless recharge module adopts the lossy driving state or the lossless driving state at the end of a frame depends on whether the last accumulated photosensitive level signal after a frame of exposure can be correctly obtained in the back-end image processing, and the deviation is minimal; The output module is used to take out the reset level signal and the photosensitive level signal; the row selection control signal is connected to the output module to control the opening and closing of the output module; when necessary, the reset level signal and the photosensitive level signal are output to the column output bus respectively through the output module; The intermittent exposure means that when the pulse reflected light of an object within a set distance interval reaches the image sensor chip, the photosensitive module starts to sense light, and after the pulse reflected light passes, the photosensitive module ends this exposure and outputs the photosensitive level signal saved after this exposure to the storage module through the transmission module; the length of the intermittent exposure repetition cycle is equal to the length of the pulse light emission repetition cycle, and each intermittent exposure time interval is shorter than the intermittent exposure repetition cycle; the method for accumulating the intermittent exposure signal is: before the first pulse reflected light echo signal to be received within the set distance interval reaches the photosensitive module, the lossless recharge module first recharges the previous exposure result stored in the storage module to the photosensitive module without loss, and then the photosensitive module starts the accumulation of this pulse reflected light exposure based on the result of the previous pulse reflected light exposure; When the last pulse reflected light echo signal of the set distance range to be received is transmitted, the perception result of the photosensitive module is transferred to the storage module via the transmission module, and then the transmission module turns off the transmission; before the first gap exposure of a frame, the photosensitive module is reset, or the reset level is losslessly fed back to the photosensitive module by the reset lossless feedback module.

2. The structure of the pixel circuit of the image sensor for non-continuous exposure as claimed in claim 1, characterized in that: After a frame of exposure begins, the exposure work of the image sensor pixel circuit selects a conventional exposure mode or an intermittent exposure mode according to an external mode control signal; when the image sensor pixel circuit selects the intermittent exposure mode, the interval exposure timing generation circuit inside the image sensor chip outputs control signals to each functional module of each pixel in a certain timing to realize intermittent exposure; Stage 1, Stage 2, Stage 3, Stage 4, Stage 5, Stage 6, Stage 7, Stage 8 respectively represent eight working stages of the image sensor pixel circuit: Stage 1 is reset and storage of reset level signal: that is, after the reset module receives the reset control signal, the reset tube in the reset module is turned on, and the reset level is sent to the photosensitive module, the storage module, the lossless recharging module and the reset storage module, which are used to reset the photosensitive diode in the photosensitive module, the storage capacitor in the storage module and the storage capacitor in the reset storage module; at the same time, the level signal in the photosensitive module is collected and stored in the storage capacitor in the reset storage module, and it lasts for the set time corresponding to this stage; Stage 2 is to sample and store the gate-source difference level: that is, the voltage difference between the gate and source of the source follower in the reset module and the lossless recharge module, that is, the gate-source difference level, is collected and stored in the compensation capacitor inside the lossless recharge module; Stage 3 is to start the backflow charge work before the arrival of a set new pulse reflection light and continue for the set time corresponding to this stage: that is, the photosensitive level signal in the storage module is superimposed on the stored gate-source difference level through the lossless recharge module, and then output to the photosensitive module through the source follower, so as to realize the lossless backflow of the last photosensitive level signal to the photosensitive module and stop after the time set in this stage; Stage 4 is intermittent exposure and continues for the set time corresponding to this stage: that is, the photosensitive The module enters the gap exposure period based on the last photosensitive level signal, and accumulates and receives new pulse reflection light echo signals, and stops after continuing for the set time corresponding to this stage; Stage 5 is to transmit and store the photosensitive level signal: that is, after the transmission module receives the transmission control signal, the photosensitive level signal received by the photosensitive module is transferred to the storage module for storage through the transmission module and the lossless recharge module when necessary; Stage 6 is to turn off the switches of all modules: that is, when the switches of all modules are in the off state, the photosensitive level signals received in the photosensitive module during the time of turning off the switches of all modules are not collected, stored, or accumulated; During this period, the interval exposure timing generation circuit in the image sensor chip determines whether the gap exposure in a frame is over? If it is over, enter stage 7; if it is not over, return to stage 2; Stage 7 is to wait for the column output bus to read the reset level signal: when necessary, after the row selection tube of the output module receives the row selection control signal, the row selection tube is turned on, and the column output bus reads the reset level signal through the reset storage module, the lossless recharge module and the output module; Stage 8 is waiting for the column output bus to read the photosensitive level signal: when necessary, after the row selection tube in the output module receives the row selection control signal, the row selection tube is turned on, and the column output bus reads the photosensitive level signal of the storage module through the storage module, the lossless recharge module and the output module; the difference between the photosensitive level signal and the reset level signal is the image data signal of the image sensor pixel circuit.

3. The structure of the pixel circuit of the image sensor for non-continuous exposure as claimed in claim 1, characterized in that: When the external mode control signal of the image sensor pixel circuit does not select the intermittent exposure mode, the conventional exposure mode is entered, and stage 11, stage 12, stage 13, stage 14, and stage 15 respectively represent the five working stages of the image sensor pixel circuit: stage 11 is resetting and storing the reset level signal: that is, after the reset module receives the reset control signal, the reset tube in the reset module is turned on, and the reset level is sent to the photosensitive module, the storage module, the lossless recharging module and the reset storage module, which are used to reset the photosensitive diode in the photosensitive module, the storage capacitor in the storage module and the storage capacitor in the reset storage module; at the same time, the reset level signal in the photosensitive module is collected and stored in the storage capacitor in the reset storage module; the reset time is set by the system; stage 12 is continuous exposure for the set time: that is, the photosensitive module continuously receives and accumulates external light signals, and stops after the set time of this stage; stage 13 is transmission and storage of photosensitive level signals: that is, the transmission module receives the transmission control signal After that, the light-sensing level signal received by the light-sensing module is transmitted to the storage module for storage through the transmission module and, when necessary, through the lossless recharge module; stage 14 is waiting for the column output bus to read the reset level signal: when necessary, after the row selection control signal is received by the row selection tube in the output module, the row selection tube is turned on, and the column output bus reads the reset level signal through the reset storage module, the lossless recharge module, and the output module, at which time the lossless recharge module can work in a lossless driving state or a lossy driving state as needed; stage 15 is waiting for the column output bus to read the light-sensing level signal: when necessary, after the row selection control signal is received by the row selection tube in the output module, the row selection tube is turned on, and the column output bus reads the light-sensing level signal of the storage module through the storage module, the lossless recharge module, and the output module, at which time the lossless recharge module can work in a lossless driving state or a lossy driving state as needed; the difference between the light-sensing level signal and the reset level signal is the image data signal of the pixel circuit of the image sensor.

4. The structure of the pixel circuit of the image sensor for non-continuous exposure according to claim 1, characterized in that: The pulse light sources supported by the image sensor chip using the non-continuous exposure image sensor pixel circuit include laser, infrared light, visible light, and light of various wavelength bands.

5. The structure of the pixel circuit of the image sensor for non-continuous exposure as claimed in claim 1, characterized in that: The non-continuous exposure signal supported by the non-continuous exposure image sensor pixel circuit is a series of exposure pulse signals whose pulse width and period can be changed as required.

6. The structure of the pixel circuit of the image sensor for non-continuous exposure as claimed in claim 1, characterized in that: The non-continuous exposure image sensor pixel circuit supports global shutter image sensors and rolling shutter image sensors.

7. The structure of the pixel circuit of the image sensor for non-continuous exposure as claimed in claim 1, characterized in that: The error generated by each lossless recharge of the lossless recharge module of each pixel circuit of the image sensor can be detected by a special calibration frame. In the calibration frame, the reset cycle of the stage 1 is first executed, and then the stage 2, the stage 3, and the stage 5 are repeatedly executed for a set number of times. After the set number of repetitions of these three actions are executed, the error generated by the lossless recharge module after the set number of repetitions can be obtained through the stage 7 and the stage 8. When the storage module includes multiple capacitors, and one of the capacitors can be driven by the lossless recharge module, the action in the calibration frame becomes: first execute the reset cycle of the stage 1, and then repeat the stage 2 for a set number of times, the lossless recharge module performs lossless recharge on a capacitor in the storage module, the recharged capacitor is connected in parallel with the capacitor in the storage module that has not been recharged, and the set number of repetitions of these three actions are executed. Finally, through the stage 7 and the stage 8, a more accurate value of the error generated by the lossless recharge module after the set number of repetitions can be obtained.

8. A method for implementing a non-continuous exposure image sensor pixel circuit, using the structure as described in any one or more combinations of claims 1 to 7 to complete the perception imaging of the image sensor under the illumination of a non-continuous light source or an external ambient light source.

Images