CN116095519A - Image sensors, sensor architectures, camera modules and electronics - Google Patents

Abstract

The application discloses an image sensor, sensor architecture, camera module and electronic equipment belongs to the image processing field. Comprising the following steps: the pixel array, the conversion gain selection module and the conversion gain signal buffer and driving module; the pixel array comprises N rows of pixel units and M columns of pixel units, N pixel units in the same column are connected with the conversion gain signal buffer and the driving module through first connecting wires, N pixel units in the same column are connected with the conversion gain selection module through second connecting wires, and M and N are positive integers; the conversion gain selection module is used for generating a conversion gain selection table according to pixel signals output by the pixel array, wherein the conversion gain selection table comprises conversion gain mode selection signals corresponding to each pixel unit; the conversion gain signal buffer and driving module is used for reading gain mode selection signals corresponding to each pixel unit row by row from the conversion gain selection table, and sending the gain mode selection signals to the corresponding pixel units.

Description

Image sensors, sensor architectures, camera modules and electronics

technical field

The present application belongs to the field of image processing, and specifically relates to an image sensor, a sensor structure, a camera module and electronic equipment.

Background technique

In the image sensor (Complementry Metal-Oxide Semiconductor, CMOS), the dynamic range adjustment of the image is generally realized by changing the pixel exposure time of all pixels and adjusting the overall pixel signal gain.

In related technologies, triple conversion gain high dynamic range (Triple Conversion Gain, TCG-HDR) technology, all pixels are exposed together, the output signal is amplified with different gains, and all pixel units often need to be separately high-gain After exposure in low gain mode, exposure in medium gain mode, and exposure in low gain mode, read three frames of images at a time, and then synthesize the three frames of images, and the synthesized HDR images often have color layering and signal noise due to processing defects Ratio (Signal to Noise Ratio, SNR) drop. For example, some pixels are locally overexposed or some pixels are underexposed in the output image in some scenes.

Contents of the invention

The purpose of the embodiment of the present application is to provide an image sensor, sensor architecture, camera module and electronic equipment, which can solve the problem that the conversion gain high dynamic range technology cannot perform pixel-by-pixel modulation, resulting in poor imaging effect of the output image.

In the first aspect, an embodiment of the present application provides an image sensor method, including: a pixel array, a conversion gain selection module, and a conversion gain signal buffering and driving module;

The pixel array includes N rows of pixel units and M columns of pixel units, the N pixel units in the same column are connected to the conversion gain signal buffer and drive module through the first connection line, and the N pixel units in the same column are connected to the conversion gain signal buffer and drive module. The pixel unit is connected to the conversion gain selection module through a second connection line, and both M and N are positive integers;

Wherein, the conversion gain selection module is configured to generate a conversion gain selection table according to the pixel signal output by the pixel array, and the conversion gain selection table includes a conversion gain mode selection signal corresponding to each pixel unit;

The conversion gain signal buffering and driving module is used for reading the gain mode selection signal corresponding to each pixel unit row by row from the conversion gain selection table, and sending the gain mode selection signal to the corresponding pixel unit.

In the second aspect, the embodiment of the present application provides a sensor architecture, including: a pixel layer and a circuit layer;

The pixel layer includes: a first bonding area and a pixel array, and the pixel array is communicatively connected to the first bonding area;

The circuit layer includes: a second bonding area, a conversion gain selection module, and a conversion gain signal buffering and driving module, and the second bonding area is respectively connected to the conversion gain selection module and the conversion gain signal buffering and driving module. The first bonding region is bonded to the second bonding region.

In a third aspect, an embodiment of the present application provides a camera module, including the image processor as described in the first aspect.

In a fourth aspect, an embodiment of the present application provides an electronic device, including the camera module as described in the third aspect.

In the embodiment of the present application, through the conversion gain mode selection module, the corresponding conversion gain mode selection signal can be automatically determined for each pixel unit according to the pixel signal output by each pixel unit, and further through the conversion gain signal buffer and After the drive module reads the gain mode selection signal corresponding to each pixel unit line by line from the conversion gain selection table, it transmits the gain mode selection signal to each pixel unit, and each pixel automatically converts the gain mode selection signal according to the adaptive logic within each frame time. Choose to operate in low-gain mode, medium-gain mode or high-gain mode, so as to achieve pixel-level gain adjustment, avoiding the problem of local overexposure or underexposure of some pixels caused by three exposures, and the solution of this application does not need to change the traditional The pixel structure does not change the reading and signal processing methods of the traditional image processor, and the accurate control of the gain mode selection of each pixel can be realized by using the column parallel control method.

Description of drawings

FIG. 1 is a schematic structural diagram of a pixel unit in an embodiment of the present application;

FIG. 2 is one of the structural schematic diagrams of the image sensor provided by the embodiment of the present application;

FIG. 3 is a schematic structural diagram of a conversion gain selection module provided by an embodiment of the present application;

FIG. 4 is the second structural schematic diagram of the image sensor provided by the embodiment of the present application;

FIG. 5 is a schematic structural diagram of a sensor architecture provided by an embodiment of the present application.

Detailed ways

The following will clearly describe the technical solutions in the embodiments of the present application with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, but not all of them. All other embodiments obtained by persons of ordinary skill in the art based on the embodiments in this application belong to the protection scope of this application.

The terms "first", "second" and the like in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific sequence or sequence. It should be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments of the application can be practiced in sequences other than those illustrated or described herein, and that references to "first," "second," etc. distinguish Objects are generally of one type, and the number of objects is not limited. For example, there may be one or more first objects. In addition, "and/or" in the specification and claims means at least one of the connected objects, and the character "/" generally means that the related objects are an "or" relationship.

The image sensor, sensor architecture, camera module, and electronic device provided by the embodiments of the present application will be described in detail below through specific embodiments and application scenarios with reference to the accompanying drawings.

FIG. 1 is a schematic structural diagram of a pixel unit in an embodiment of the present application. A photodiode (PD) in an optical module of the pixel unit is responsible for light sensing and photoelectric conversion within each frame time. The generated charge e- is buffered in a floating diffusion (Floating Diffusion, FD) capacitor after passing through the TX transistor switching transistor. In the Readout phase, the charge e- in the FD will be amplified by the Source Follower (SF) transistor and converted into a corresponding voltage, and then output the pixel signal PIX_OUT to the outside of the pixel after being switched by the SEL transistor. The RST transistor is responsible for resetting the FD to the voltage VDD. The realization function of the TCG function is to change the size of the FD. In the high conversion gain (High Conversion Gain, HCG) mode, the FD needs to be as small as possible. In low conversion gain (Low Conversion Gain, LCG) mode, FD needs to be as large as possible. Therefore, a middle conversion gain (Middle Conversion Gain, MCG), LCG transistor switch and capacitors C1 and C2 are added in the pixel circuit. The MCG transistor switch is responsible for the mode conversion between HCG and MCG, and the capacitor C1 is responsible for expanding the FD capacitor. The LCG transistor switch is responsible for the mode conversion of the LCG, and the capacitor C2 is responsible for further expanding the FD capacitor. When the pixel needs to be under HCG, the MCG and LCG transistor switches are turned off, and the FD is responsible for receiving the charge e- transferred from the PD. When the pixel needs to be in MCG mode, the MCG transistor is closed to expand the connection between FD and C1 (the RST transistor switch must be kept open to prevent reset). Therefore, the charge e- transferred from PD is FD+C1. When the pixel needs to be in LCG mode, the MCG and LCG transistors are closed at the same time to expand the connection between FD and C1 and C2 (the RST transistor switch must be kept open to prevent reset). Therefore, the charge e- transferred from PD is FD+C1+C2. In short, the essential way to realize the TCG function is to change the size of the FD capacitor according to the needs.

FIG. 2 is one of the schematic structural diagrams of the image sensor provided by the embodiment of the present application, as shown in FIG. 2 , including: a pixel array 11, a conversion gain selection module 12, and a conversion gain signal buffering and driving module 13;

The pixel array 11 includes N rows of pixel units 110 and M columns of pixel units 110, and the N pixel units 110 in the same column are connected to the conversion gain signal buffering and driving module 13 through a first connection line, and in the same column The N pixel units 110 are connected to the conversion gain selection module 12 through a second connection line, and both M and N are positive integers;

Wherein, the conversion gain selection module 12 is configured to generate a conversion gain selection table according to the pixel signal output by the pixel array 11, and the conversion gain selection table includes a conversion gain mode selection signal corresponding to each pixel unit;

The conversion gain signal buffering and driving module 13 is used for reading the gain mode selection signal corresponding to each pixel unit row by row from the conversion gain selection table, and sending the gain mode selection signal to the corresponding pixel unit.

Specifically, the pixel array described in the embodiment of the present application includes a plurality of pixel units, which may specifically include N pixel rows in the same row, and M pixel columns in the same column, corresponding to each pixel array. NxM pixel units.

In the embodiment of the present application, in order to further save the wiring space, the N pixel units in the same pixel column will be connected to the conversion gain signal buffer and the driving module through the same first connection line, and the N pixel units in the same pixel column will also be connected through the same first connection line. The same second connection line is connected with the conversion gain selection module.

In the embodiment of the present application, the working period of each pixel unit in each frame (Frame) is divided into three: a reset period (Reset), an exposure period (Exposure), and a readout period (Readout). The row driver of the pixel array controls the reset and read related signals of each row of pixels, and there is a certain time difference between the reset and read between rows. In this way, there is a time difference between the output of pixels in each row and the pixel signals of pixels in other rows, so that the column-parallel ADC can only process the pixel signals output by one row of pixels at a time. Each row of pixels directly enters the next frame time after the reading is completed, and there is no need to care about the status of other rows of pixels. When all the rows of pixels are read, the pixel signal corresponding to one frame is output to the conversion gain selection module.

In the embodiment of the present application, the pixel signal output by the pixel array may be a signal output by the pixel unit after reset and exposure processing in the current frame, and the output pixel signal of each pixel unit may be a different pixel signal. In the embodiment of the present application, the conversion gain selection module may determine the gain mode selection signal corresponding to each pixel unit in the next frame according to the pixel signal of the current frame.

In an optional embodiment, the conversion gain selection module is used to determine the corresponding gain mode selection signal according to the pixel signal output by each pixel unit, and then generate the conversion gain according to the gain mode selection signal corresponding to each pixel unit Select table.

The gain mode selection signal corresponding to each pixel unit is recorded in the conversion gain selection table in the embodiment of the present application. Optionally, the gain mode selection signals in the conversion gain selection table may be sorted according to the arrangement of the pixel array.

In an optional embodiment, the conversion gain selection module may include a row buffer submodule and a row driver submodule, and the row buffer submodule in the conversion gain selection module may read each pixel row by row according to the pixel row arrangement of the pixel array For the gain mode selection signal corresponding to the unit, the row buffer sub-module of the conversion gain signal buffer and drive module can only buffer the gain mode selection signal of one row of pixel units at a time.

In the process of rolling shutter exposure, when the pixel unit of a certain row in the pixel array enters the readout period (Readout Period) and needs to provide a gain mode selection signal for reading mode selection, the row driving submodule drives the row buffer submodule The module sends the buffered gain mode selection signal to the pixel units of the corresponding row.

More specifically, the gain mode selection signal corresponding to each pixel unit can be a digital signal or an analog signal, and the gain mode selection signal will control the pixel unit to follow the gain mode indicated by the gain mode selection signal within the time of the next image frame. Pixel signal output is performed.

In the embodiment of the present application, through the conversion gain mode selection module, the corresponding conversion gain mode selection signal can be automatically determined for each pixel unit according to the pixel signal output by each pixel unit, and further through the conversion gain signal buffer and After the drive module reads the gain mode selection signal corresponding to each pixel unit line by line from the conversion gain selection table, it transmits the gain mode selection signal to each pixel unit, and each pixel automatically converts the gain mode selection signal according to the adaptive logic within each frame time. Choose to operate in low-gain mode, medium-gain mode or high-gain mode, so as to achieve pixel-level gain adjustment, avoiding the problem of local overexposure or underexposure of some pixels caused by three exposures, and the solution of this application does not need to change the traditional The pixel structure does not change the reading and signal processing methods of the traditional image processor, and the accurate control of the gain mode selection of each pixel can be realized by using the column parallel control method.

Optionally, the conversion gain selection module includes: a first comparator, a second comparator, and a conversion gain indicator, and the conversion gain indicator is respectively connected in communication with the first comparator and the second comparator;

The first comparator is used to compare the pixel signal corresponding to each pixel unit with a first preset threshold signal to obtain a first comparator output signal corresponding to each pixel unit;

The second comparator is used to compare the pixel signal corresponding to each pixel unit with a second preset threshold signal to obtain a second comparator output signal corresponding to each pixel unit;

The conversion gain indicator is used to buffer the first comparator output signal and the second comparator output signal, and generate the conversion gain according to the first comparator output signal and the second comparator output signal Select table.

FIG. 3 is a schematic structural diagram of the conversion gain selection module provided by the embodiment of the present application. As shown in FIG. The first comparator 21 and the second comparator 22 are connected in communication.

In an optional embodiment, the first comparator and the second comparator may be digital comparators, and the sum of the first preset threshold signal may be a threshold preset by the user, which may specifically be a fixed preset threshold signal. Optionally, when comparing pixel signals of different pixel units, different first preset threshold signals and second preset threshold signals may also be set.

In an optional embodiment, the first preset threshold signal and the second preset threshold signal may be the same threshold signal or different threshold signals.

In an optional embodiment, the first preset threshold signal may be used to determine whether the MCG mode is selected or not, and the second preset threshold signal may be used to determine whether the LCG mode is selected or not. In the pixel signal In the case of binary digital signals, the first preset threshold signal and the second preset threshold signal may also be binary 10-bit binary numbers.

In an optional embodiment, after the image data output for each pixel unit is converted into a data signal, it can be compared with the first preset threshold signal preset by the user and entered into the first comparator (COMP), For the signal output by each pixel, a comparison result can be obtained, and then the corresponding first comparator output signal of each pixel unit can be obtained.

Correspondingly, it can also enter the second comparator for comparison with the second preset threshold signal preset by the user. For the signal output by each pixel, a comparison result can be obtained, and then the corresponding first threshold value of each pixel unit can be obtained. Two comparator output signals.

In an optional embodiment, since there may be a certain time difference between the output of the comparison result of the first comparator and the second comparator, a conversion gain indicator is required to buffer the output signal of the first comparator and the output signal of the second comparator. The second comparator outputs a signal.

After the two comparison results of each pixel are completed, the comparison result will be transferred to the conversion gain selection table for storage, and after the comparison of all pixel units is completed, the conversion gain selection table will be obtained.

In the embodiment of the present application, the pixel signals output by different pixel units can be effectively analyzed through the first comparator and the second comparator, so as to effectively obtain a gain mode suitable for each pixel unit, and effectively ensure that the final generated picture quality, and effectively buffer the first comparator output signal and the second comparator output signal through the conversion gain indicator, and generate a conversion gain selection table.

Optionally, the first comparator is specifically used for:

When the pixel signal is greater than the first preset threshold signal, the first output signal of the comparator corresponding to the pixel unit is a first high-level output signal;

When the pixel signal is less than or equal to the first preset threshold signal, the first output signal of the comparator corresponding to the pixel unit is a first low-level output signal;

The second comparator is specifically used for:

When the pixel signal is greater than the second preset threshold signal, the output signal of the second comparator corresponding to the pixel unit is a second high-level output signal;

When the pixel signal is less than or equal to the second preset threshold signal, the output signal of the second comparator corresponding to the pixel unit is a second low-level output signal.

Specifically, in this embodiment of the application, the high-level output signal can be recorded as "1" in the conversion gain selection table, and the low-level output signal can be recorded as "0" in the conversion gain selection table. For each pixel output A comparison result can be obtained for each signal, and it is cached in the conversion gain selection table according to the position of the pixel unit in the pixel array. It is agreed that the binary digital signal "1" means that the pixel enters the high-gain mode for reading, and the binary digital signal "0 " stands for putting the pixel into low gain mode for reading. It can also be agreed to be used in reverse during specific implementation, but a 1-bit binary signal must be used.

In an optional embodiment, if the user does not need the TCG-HDR function, the conversion gain signal buffering and driving module can be forcibly shielded, and its operation can be stopped.

The conversion gain indicator is specifically used for:

When the first comparator output signal is a first high-level output signal, and the second comparator output signal is a second high-level output signal, the gain mode selection signal of the pixel unit is obtained as Low gain mode selection signal;

When the first comparator output signal is a first low-level output signal, and the second comparator output signal is a second high-level output signal, the gain mode selection signal of the pixel unit is obtained as Medium gain mode selection signal;

In the case that the first comparator output signal is a first high-level output signal, and the second comparator output signal is a second low-level output signal, the gain mode selection signal of the pixel unit is obtained as Low gain mode selection signal;

In the case where the first comparator output signal is a first low-level output signal, and the second comparator output signal is a second low-level output signal, the gain mode selection signal of the pixel unit is obtained as High gain mode selection signal.

In an optional embodiment, when the output signal of the first comparator is the first high-level output signal, it means that the low-gain mode is selected for the first comparison, and the output signal of the second comparator is the second high-level output signal. In the case of a flat output signal, it means that the middle gain mode is selected for the second comparison, and at this time, the gain mode selection signal of the final pixel unit is a low gain mode selection signal.

In an optional embodiment, the output signal of the first comparator is the first low-level output signal, which means that the low-gain mode is not selected for the first comparison, and the output signal of the second comparator is the second high-level output signal In the case of , it means that the middle gain mode is selected for the second comparison, and finally the gain mode selection signal of the pixel unit is obtained as the middle gain mode selection signal.

In an optional embodiment, the output signal of the first comparator is the first high-level output signal, which means that the low-gain mode is selected for the first comparison, and the output signal of the second comparator is the second low-level output signal. In the case of a flat output signal, it means that the middle gain mode is not selected for the second comparison, and the gain mode selection signal of the pixel unit is obtained as a low gain mode selection signal;

In an optional embodiment, the output signal of the first comparator is the first level output signal, which means that the low gain mode is not selected for the first comparison, and the output signal of the second comparator is the second low level output signal. In the case of a flat output signal, it means that the middle gain mode is not selected for the second comparison, and the gain mode selection signal of the pixel unit is obtained as a high gain mode selection signal;

In an optional embodiment, when the pixel array of any column of the pixel array is in the read period and needs to determine the HCG or MCG or LCG read mode selection, the conversion gain signal buffer and drive module will push the buffered 2-bit conversion gain The selection signal is used as an LCG signal and an MCG signal, and after being driven by a corresponding column driver, it is transmitted to the pixel array and provided to the pixels of this column for reading in LCG, MCG or HCG mode. Here, it is agreed that the digital signals "LCG=1 and MCG=1" represent that the pixel enters the LCG mode for reading, and the digital signal "LCG=0 and MCG=1" represents that the pixel enters the MCG mode for reading, and the digital signal "LCG=0 and MCG=0" means to let the pixel enter HCG mode reading. If the user does not need the adaptive TCG-HDR function, force the column-parallel TCG mode signal buffer and the column buffer in the driver module to store/cache the binary digital signal "0" or "1"

In the embodiment of the present application, the comparator can effectively perform targeted analysis on the pixel signals output by different pixel units, thereby effectively obtaining a gain mode suitable for each pixel unit, and effectively ensuring the quality of the final generated picture.

Optionally, the conversion gain selection module includes: an independent image signal processor;

The independent image signal processor is used to analyze the pixel signal output by the pixel array pixel by pixel according to the stored program algorithm, and obtain the gain mode selection signal corresponding to each pixel unit;

The conversion gain selection table is generated according to the gain mode selection signal corresponding to each pixel unit.

Specifically, in the embodiment of the present application, the program algorithm can specifically analyze the image data of each pixel unit and determine the algorithm of each pixel gain mode, and the algorithm can specifically input the pixel of each pixel unit After the signal, the algorithm that can output the corresponding gain mode selection signal.

In an optional embodiment, the comparator may be simulated by a program algorithm, and then the pixel signal output by the pixel array is analyzed pixel by pixel to obtain the gain mode selection signal corresponding to each pixel unit. The algorithm is also It may be other algorithms that can realize corresponding functions.

In an optional embodiment, after obtaining the gain mode selection signal corresponding to each of the pixel units, the gain mode selection signal may be further stored in a corresponding position according to the arrangement of the pixel array and according to the row and column distribution of the pixel unit, Get the final conversion gain selection table.

In an optional embodiment, the stored program algorithm may be stored inside the image sensor, or integrated outside the image sensor.

And when the program algorithm is integrated outside the image sensor, it may be stored in an independent image signal processor outside the image sensor.

In the embodiment of the present application, through the program algorithm integrated by the software program module, the pixel unit can be analyzed one by one by software, and the number of transistors of the image sensor can be effectively reduced and the cost can be saved under the premise of effectively ensuring the image quality.

Optionally, the sensor further includes: an interface module, the interface module is respectively connected in communication with the conversion gain signal buffering and driving module and the pixel array;

The interface module is used to transmit the pixel signal output by the pixel array to the independent image signal processor, and receive the gain mode selection signal corresponding to each pixel unit transmitted by the independent image signal processor.

In an optional embodiment, the interface module may specifically be an interface for data transmission with an independent image signal processor.

FIG. 4 is the second structural diagram of the image sensor provided by the embodiment of the present application. As shown in FIG. 4 , it includes: a pixel array 11 , an independent image signal processor 31 , a conversion gain signal buffering and driving module 13 and an interface module 32 .

In the embodiment of the present application, the interface module is respectively connected to the conversion gain signal buffer and drive module and the pixel array, and the interface module can transmit the pixel signal of each pixel unit in the pixel array to an independent image signal processor, so that the independent The image signal processor can analyze the gain mode corresponding to each pixel unit according to the pixel signal to obtain a conversion gain selection table.

Then the interface module can also receive the gain mode selection signal of each column of pixel units sent by the independent image signal processor.

In the embodiment of the present application, the interface module can effectively send the image data to the independent image signal processor for gain mode analysis, and accept the gain mode selection signal corresponding to each pixel unit sent back by the independent image signal processor, which can effectively reduce the The number of transistors effectively guarantees the image quality.

Optionally, the pixel array further includes: a signal reading module, the N pixel units in the same column are connected to the signal reading module through the second connection line;

The signal reading module is used to convert the pixel signal output by each pixel unit to the conversion gain selection module after analog-to-digital conversion.

In an optional embodiment, in each frame time, after each pixel unit is reset and exposed, it will enter a reading phase, and the signal reading module will read the image data generated by each pixel unit at this time.

After the signal reading module reads the image data, the image data at this time is often an analog signal, which is not convenient for subsequent direct processing. Therefore, it can be processed by analog-to-digital conversion. After converting it into a digital signal, the It is passed to the high dynamic range logic block.

In an optional embodiment, the signal reading module may include an analog-to-digital conversion module and an image signal processor, the analog-to-digital conversion module is connected to the image signal processor, and the N pixel units in the same column are connected through the second The line is connected to the conversion gain selection module via the signal reading module.

In the embodiment of the present application, by performing analog-to-digital conversion on the pixel signals output by each of the pixel units, it can effectively ensure that the pixel signals can be effectively analyzed subsequently.

FIG. 5 is a schematic structural diagram of the sensor architecture provided by the embodiment of the present application, as shown in FIG. 5 , including: a pixel layer 51 and a circuit layer 52;

The pixel layer 51 includes: a first bonding area 510 and a pixel array 11, and the pixel array 11 is communicatively connected to the first bonding area 510;

The circuit layer 52 includes: a second bonding area 520, a conversion gain selection module 12 and a conversion gain signal buffering and driving module 13, and the second bonding area 520 is connected to the conversion gain selection module 12 and the conversion gain signal buffering and driving module 13 respectively. The driving module 13 is connected in communication, and the first bonding area 510 is bonded to the second bonding area 520 .

Specifically, in the embodiment of the present application, the pixel layer and the circuit layer may be specifically composed of a silicon wafer layer, the pixel layer is specifically a pixel silicon wafer layer, and all pixel units are arranged on the pixel layer, and the pixel layer may specifically use a front-lit Type (Front-Side Illumination, FSI), can also be used to back-illuminated (Back-Side Illumination, BSI) process.

In the embodiment of the present application, an effective pixel array is arranged on the pixel layer, and a first bonding area may be provided around the pixel array for signal wiring, so as to realize the connection between the pixel layer and the circuit layer.

The pixel layer silicon chip only places the pixel array (Pixel Array), and all the input and output signals of the pixel are provided by the underlying circuit layer silicon chip. The signal connection between the two layers adopts TSV (Trans-Silicon Via, through-silicon via) or Cu-Cu Hybrid Bonding (copper-copper hybrid bonding).

The conversion gain selection module, the conversion gain signal buffer and drive module, and the interface module can all be arranged in the circuit layer.

In an optional embodiment, when the conversion gain selection module is integrated in the software of the pixel sensor, no high dynamic range logic module is provided in the corresponding circuit layer.

The external HDR logic software can be signal-connected with the column-parallel TCG mode signal buffer and drive module through the I/O pins of the image sensor under the coordination of the port module.

In the embodiment of the present application, through the conversion gain mode selection module, the corresponding conversion gain mode selection signal can be automatically determined for each pixel unit according to the pixel signal output by each pixel unit, and further through the conversion gain signal buffer and After the drive module reads the gain mode selection signal corresponding to each pixel unit line by line from the conversion gain selection table, it transmits the gain mode selection signal to each pixel unit, and each pixel automatically converts the gain mode selection signal according to the adaptive logic within each frame time. Choose to operate in low-gain mode, medium-gain mode or high-gain mode, so as to achieve pixel-level gain adjustment, avoiding the problem of local overexposure or underexposure of some pixels caused by three exposures, and the solution of this application does not need to change the traditional The pixel structure does not change the reading and signal processing methods of the traditional image processor, and the accurate control of the gain mode selection of each pixel can be realized by using the column parallel control method.

Optionally, the embodiment of the present application also provides a camera module including the above-mentioned image sensor, through which the camera module can perform pixel-by-pixel modulation during the process of realizing the TCG-HDR function, effectively ensuring the imaging effect of the output image .

Optionally, an embodiment of the present application further provides an electronic device, the electronic device includes the camera module in the foregoing embodiments, and the electronic device may be a terminal or other devices except the terminal. Exemplarily, the electronic device may be a mobile phone, a tablet computer, a notebook computer, a handheld computer, a vehicle electronic device, a mobile Internet device (MobileInternet Device, MID), an augmented reality (augmented reality, AR)/virtual reality (virtual reality, VR) device, robot, wearable device, ultra-mobile personal computer (ultra-mobile personal computer, UMPC), netbook or personal digital assistant (personal digital assistant, PDA), etc., can also serve as server, network attached storage (Network Attached Storage, NAS ), a personal computer (personal computer, PC), a television (television, TV), a teller machine or a self-service machine, etc., are not specifically limited in this embodiment of the present application.

The electronic device in this embodiment of the present application may be a device with an operating system. The operating system may be an Android operating system, an iOS operating system, or other possible operating systems, which are not specifically limited in this embodiment of the present application.

It should be noted that, in this document, the term "comprising", "comprising" or any other variation thereof is intended to cover a non-exclusive inclusion such that a process, method, article or apparatus comprising a set of elements includes not only those elements, It also includes other elements not expressly listed, or elements inherent in the process, method, article, or device. Without further limitations, an element defined by the phrase "comprising a ..." does not preclude the presence of additional identical elements in the process, method, article, or apparatus comprising that element. In addition, it should be pointed out that the scope of the methods and devices in the embodiments of the present application is not limited to performing functions in the order shown or discussed, and may also include performing functions in a substantially simultaneous manner or in reverse order according to the functions involved. Functions are performed, for example, the described methods may be performed in an order different from that described, and various steps may also be added, omitted, or combined. Additionally, features described with reference to certain examples may be combined in other examples.

Through the description of the above embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus a necessary general-purpose hardware platform, and of course also by hardware, but in many cases the former is better implementation. Based on such an understanding, the technical solution of the present application can be embodied in the form of computer software products, which are stored in a storage medium (such as ROM/RAM, disk, etc.) , optical disc), including several instructions to enable a terminal (which may be a mobile phone, computer, server, or network device, etc.) to execute the methods described in the various embodiments of the present application.

The embodiments of the present application have been described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementations. The above-mentioned specific implementations are only illustrative and not restrictive. Those of ordinary skill in the art will Under the inspiration of this application, without departing from the purpose of this application and the scope of protection of the claims, many forms can also be made, all of which belong to the protection of this application.

Claims (10)

1. An image sensor, comprising: a pixel array, a conversion gain selection module and a conversion gain signal buffer and a drive module; The pixel array includes N rows of pixel units and M columns of pixel units, and the N 5 pixel units in the same column are connected to the conversion gain signal buffer and the driving module through the first connection line, and the N 5 pixel units in the same column are connected to the drive module through the first connection line. The pixel unit is connected to the conversion gain selection module through a second connection line, and both M and N are positive integers; Wherein, the conversion gain selection module is configured to generate a conversion gain selection table according to the pixel signal output by the pixel array, and the conversion gain selection table includes a conversion gain mode selection signal corresponding to each pixel unit; The conversion gain signal buffering and driving module is used for reading the gain mode selection signal corresponding to each pixel unit row by row from the conversion gain selection table, and sending the gain mode selection signal to the corresponding pixel unit. 2. The image sensor according to claim 1, wherein the conversion gain selection module 5 includes: a first comparator, a second comparator and a conversion gain indicator, and the conversion gain indicator is respectively connected to The first comparator and the second comparator are connected in communication; The first comparator is used to compare the pixel signal corresponding to each pixel unit with a first preset threshold signal to obtain a first comparator output signal corresponding to each pixel unit; The second comparator is used to compare the pixel signal corresponding to each pixel unit with the second preset threshold signal 0 to obtain a second comparator output signal corresponding to each pixel unit; The conversion gain indicator is used to buffer the first comparator output signal and the second comparator output signal, and generate the conversion gain according to the first comparator output signal and the second comparator output signal Select table. 3. The image sensor according to claim 2, wherein the first comparator is specifically used for: When the pixel signal is greater than the first preset threshold signal, the first output signal of the comparator corresponding to the pixel unit is a first high-level output signal; When the pixel signal is less than or equal to the first preset threshold signal, the first output signal of the comparator corresponding to the pixel unit is a first low-level output signal; The second comparator is specifically used for: When the pixel signal is greater than the second preset threshold signal, the output signal of the second comparator corresponding to the pixel unit is a second high-level output signal; When the pixel signal is less than or equal to the second preset threshold signal, the output signal of the second comparator corresponding to the pixel unit is a second low-level output signal. 4. The image sensor according to claim 3, wherein the conversion gain indicator is specifically used for: When the first comparator output signal is a first high-level output signal, and the second comparator output signal is a second high-level output signal, the gain mode selection signal of the pixel unit is obtained as Low gain mode selection signal; When the first comparator output signal is a first low-level output signal, and the second comparator output signal is a second high-level output signal, the gain mode selection signal of the pixel unit is obtained as Medium gain mode selection signal; In the case that the first comparator output signal is a first high-level output signal, and the second comparator output signal is a second low-level output signal, the gain mode selection signal of the pixel unit is obtained as Low gain mode selection signal; In the case where the first comparator output signal is a first low-level output signal, and the second comparator output signal is a second low-level output signal, the gain mode selection signal of the pixel unit is obtained as High gain mode selection signal. 5. The image sensor according to claim 1, wherein the conversion gain selection module comprises: an independent image signal processor; The independent image signal processor is used to analyze the pixel signal output by the pixel array pixel by pixel according to the stored program algorithm, and obtain the gain mode selection signal corresponding to each pixel unit; The conversion gain selection table is generated according to the gain mode selection signal corresponding to each pixel unit. 6. The image sensor according to claim 5, characterized in that, the sensor further comprises: an interface module, the interface module is respectively connected to the conversion gain signal buffering and driving module and the pixel array in communication; The interface module is used to transmit the pixel signal output by the pixel array to the independent image signal processor, and receive the gain mode selection signal corresponding to each pixel unit transmitted by the independent image signal processor. 7. The image sensor according to claim 1, wherein the pixel array further comprises: a signal reading module, and the N pixel units in the same column are connected to the signal reading module through the second connection line. Take the module connection; The signal reading module is used to convert the pixel signal output by each pixel unit to the conversion gain selection module after analog-to-digital conversion. 8. A sensor architecture based on the image sensor according to any one of claims 1-7, comprising: a pixel layer and a circuit layer; The pixel layer includes: a first bonding area and a pixel array, and the pixel array is communicatively connected to the first bonding area; The circuit layer includes: a second bonding area, a conversion gain selection module, and a conversion gain signal buffering and driving module, and the second bonding area is respectively connected to the conversion gain selection module and the conversion gain signal buffering and driving module. The first bonding region is bonded to the second bonding region. 9. A camera module, comprising the image sensor according to any one of claims 1-7. 10. An electronic device, comprising the camera module according to claim 9.

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