Image sensing device and imaging apparatus including the same

Abstract

This application relates to an image sensing device and an imaging device including the same. An image sensing device may include: a first test block comprising a plurality of first image sensing pixels and a first heating element, wherein the first image sensing pixels are configured to convert incident light carrying an image into a first pixel signal indicating the image, and the first heating element is configured to transfer heat to the first image sensing pixels; a second test block comprising a plurality of second image sensing pixels and a second heating element, each second image sensing pixel including a light-blocking structure to be shielded from receiving incident light and generating a second pixel signal without direct exposure to incident light, and the second heating element being configured to transfer heat to the second image sensing pixel; and a readout block configured to process the first pixel signal output from the first test block and the second pixel signal output from the second test block.

Description

Technical Field

[0001] The technology and implementation disclosed in this patent document generally relate to an image sensing device that generates image data in response to incident light and an imaging device including the image sensing device. Background Technology

[0002] Image sensing devices are used to capture optical images by converting light into electrical signals using photosensitive semiconductor materials that react with light. With the development of the automotive, medical, computer, and communications industries, the demand for high-performance image sensing devices is constantly increasing in various fields such as smartphones, digital cameras, game consoles, IoT (Internet of Things), robotics, security cameras, and medical miniature cameras.

[0003] Image sensing devices can be broadly categorized into CCD (Charge-Coupled Device) image sensing devices and CMOS (Complementary Metal-Oxide-Semiconductor) image sensing devices. Compared to CMOS image sensing devices, CCD image sensing devices offer better image quality, but they tend to consume more power and are larger in size. CMOS image sensing devices are smaller and consume less power than CCD image sensing devices. Furthermore, CMOS sensors are manufactured using CMOS fabrication technology, allowing the photosensitive element and other signal processing circuitry to be integrated into a single chip, enabling the production of miniaturized image sensing devices at a lower cost. For these reasons, CMOS image sensing devices are being developed for many applications, including mobile devices. Summary of the Invention

[0004] Various embodiments of the disclosed technology relate to an image sensing device that can reduce dark noise and an imaging device that includes the image sensing device.

[0005] According to an embodiment of the disclosed technology, an image sensing device may include: a first test block comprising a plurality of first image sensing pixels and a first heating element, wherein the first image sensing pixels are configured to convert incident light carrying an image into a first pixel signal indicating the image, and the first heating element is configured to transfer heat to the first image sensing pixels; a second test block comprising a plurality of second image sensing pixels and a second heating element, wherein each second image sensing pixel includes a light blocking structure to be shielded from receiving incident light and generating a second pixel signal without being directly exposed to incident light, and the second heating element is configured to transfer heat to the second image sensing pixel; and a readout block configured to process the first pixel signal output from the first test block and the second pixel signal output from the second test block.

[0006] According to another embodiment of the disclosed technology, an imaging apparatus may include: an image sensing device including a plurality of active image sensing pixels and a plurality of optical black pixels, wherein the plurality of active image sensing pixels are configured to convert incident light carrying an image into image data indicating the image, and the plurality of optical black pixels are shielded to prevent the incident light from generating noise data indicating noise in the image data; and an image signal processor configured to: correct the noise data using pedestal information corresponding to the temperature of the image sensing device; and subtract the corrected noise data from the image data. The image sensing device includes: a first test block comprising a plurality of first image sensing pixels and a first heating element, wherein the first image sensing pixels are configured to convert incident light carrying an image into a first pixel signal indicating the image, and the first heating element is configured to transfer heat to the first image sensing pixels; a second test block comprising a plurality of second image sensing pixels and a second heating element, wherein the second image sensing pixels include a light-blocking structure to be shielded from receiving incident light and to generate a second pixel signal without being directly exposed to incident light, and the second heating element is configured to transfer heat to the second image sensing pixels; and a base information storage circuit configured to store base information related to the first pixel signal of the active pixels and the second pixel signal of the optical black pixels.

[0007] It should be understood that the foregoing general description of the disclosed technology and the following detailed description are illustrative and explanatory, and are intended to provide a further explanation of the claimed disclosure. Attached Figure Description

[0008] Figure 1 This is a block diagram illustrating examples of imaging devices based on some implementations of the disclosed technology.

[0009] Figure 2 This is a graph illustrating the increase in dark current of active pixels and optical black pixels due to temperature increase in some implementations based on the disclosed technology.

[0010] Figure 3 These are examples of some implementations based on the disclosed technology. Figure 1 A block diagram of an example pixel array is shown.

[0011] Figure 4A These are examples of some implementations based on the disclosed technology. Figure 3 A schematic diagram of an example of an active test block is shown.

[0012] Figure 4B These are examples of some implementations based on the disclosed technology. Figure 4A The cross-sectional view of an example of an active test block cut by the first cutting line is shown.

[0013] Figure 5A These are examples of some implementations based on the disclosed technology. Figure 3 A schematic diagram of an example of an optical black (OB) test block.

[0014] Figure 5B These are examples of some implementations based on the disclosed technology. Figure 5A The cross-sectional view of an example optical black (OB) test block cut by the second cutting line is shown.

[0015] Figure 6 This is a flowchart illustrating example methods for obtaining base information based on some implementations of the disclosed technology.

[0016] Figure 7 This is a flowchart illustrating example methods for performing base calibration using base information, based on some implementations of the disclosed technology. Detailed Implementation

[0017] This patent document provides an image sensing device capable of generating image data in response to incident light, and implementations and examples of an imaging device including the image sensing device. The disclosed technology can be implemented in some embodiments to provide an image sensing device capable of reducing dark noise under different conditions. In some implementations, the image sensing device includes a test block for generating pedestal information, allowing each image sensing device chip to store independent pedestal information to perform pedestal correction operations on a chip-by-chip basis. In this way, the dark noise component contained in the image data can be more accurately reflected in image correction.

[0018] Implementations of the disclosed technology will now be described in detail, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numerals will be used throughout the drawings to refer to the same or similar components. While this disclosure is readily adaptable to various modifications and alternatives, specific embodiments thereof are shown by way of example in the drawings. However, this disclosure should not be construed as limiting itself to the embodiments set forth herein.

[0019] In the following description, various embodiments will be illustrated with reference to the accompanying drawings. However, it should be understood that the disclosed technology is not limited to the specific embodiments, but includes various modifications, equivalents, and / or substitutions of the embodiments. Embodiments of the disclosed technology can provide various effects that can be directly or indirectly recognized through the disclosed technology.

[0020] Figure 1 This is a block diagram illustrating an example of an imaging device 10 based on some implementations of the disclosed technology.

[0021] Reference Figure 1Imaging device 10 may include any mechanical or electronic device capable of capturing still or moving images, such as a digital still camera for capturing still images or a digital video camera for capturing moving images. Examples of imaging devices may include digital SLR (DSLR) cameras, mirrorless cameras, or mobile phones (e.g., smartphones). Imaging device 10 may include a device having both a lens and an image pickup element, enabling the device to capture (or photograph) a target object and thus create an image of the target object.

[0022] The imaging device 10 may include an image sensing device 100 and an image signal processor 200.

[0023] Image sensing device 100 can detect incident light and convert the incident light into charge carriers carrying an image in the incident light. Examples of image sensing device 100 may include a complementary metal-oxide-semiconductor (CMOS) image sensor (CIS) for converting optical signals into electrical signals. Image sensing device 100 can provide image signal processor 200 with image data (IDATA) obtained by converting optical signals into electrical signals. Image signal processor 200 can use sensor control signals (SCS) to control the operation of image sensing device 100, such as power switching operation, operation for switching between different operating modes, and operation for adjusting the sensitivity of image sensing device 100.

[0024] The image sensing device 100 may include a pixel array 110, a row driver 120, a correlated dual sampler (CDS) 130, an analog-to-digital converter (ADC) 140, an output buffer 150, a column driver 160, a timing controller 170, a temperature sensor 180, and a base information storage device 190. This is discussed by way of example only. Figure 1 The components of the image sensing device 100 shown and Figure 1 The components of the image sensing device 100 shown are not to be construed as limiting. Therefore, the image sensing device 100 may also include... Figure 1 Other components shown.

[0025] Pixel array 110 may include multiple unit pixels (e.g., unit imaging pixels or unit image sensing pixels) arranged in rows and columns. In one example, the multiple unit pixels may be arranged as a two-dimensional (2D) pixel array including rows and columns. In another example, the multiple unit pixels may be arranged as a three-dimensional (3D) pixel array.

[0026] Multiple unit pixels can generate electrical signals based on unit pixels or pixel groups, where a pixel group includes multiple unit pixels that can share at least some internal circuitry.

[0027] Multiple unit pixels may include at least one active pixel and at least one optical black (OB) pixel. The active pixel senses incident light and generates a pixel signal corresponding to the intensity of the incident light. The optical black pixel may have substantially the same structure as the active pixel, except for the structure used to block the incident light. The optical black pixel is shielded from receiving light incident on its surface and is used to generate a pixel signal without being exposed to incident light. The pixel output signal from the optical black pixel is used to reduce noise in the image generated by the active pixel.

[0028] The pixel array 110 can receive drive signals from the row driver 120, including row selection signals, pixel reset signals, and transmission signals. Once a drive signal is received, the corresponding imaging pixel in the pixel array 110 can be activated to perform the operation corresponding to the row selection signal, pixel reset signal, and transmission signal.

[0029] The row driver 120 can activate the pixel array 110 to perform certain operations on the imaging pixels in the corresponding rows based on command and control signals provided by controller circuitry such as timing controller 170. In some implementations, the row driver 120 can select one or more imaging pixels arranged in one or more rows of the pixel array 110. The row driver 120 can generate a row selection signal to select one or more rows among a plurality of rows. The row driver 120 can sequentially enable a pixel reset signal for resetting the imaging pixel corresponding to at least one selected row, and a transmission signal for the pixel corresponding to at least one selected row. Thus, a reference signal and an image signal, as analog signals generated by each of the imaging pixels in the selected rows, can be sequentially transmitted to the CDS 130. The reference signal can be an electrical signal provided to the CDS 130 when the sensing node (e.g., a floating diffusion node) of the imaging pixel is reset, and the image signal can be an electrical signal provided to the CDS 130 when photocharge generated by the imaging pixel accumulates in the sensing node. The reference signal, indicating the unique reset noise of each pixel, and the image signal, indicating the intensity of the incident light, can be collectively referred to as pixel signals as needed.

[0030] CMOS image sensors can use Correlated Double Sampling (CDS) to remove unwanted offset values ​​of pixels, known as fixed-pattern noise, by removing the difference between the two samples of the pixel signal through two samplings. In one example, Correlated Double Sampling (CDS) removes unwanted offset values ​​of pixels by comparing the pixel output voltage obtained before and after the accumulation of photocharge generated by incident light in the sensing node, making it possible to measure the pixel output voltage based solely on the incident light. In some embodiments of the disclosed art, CDS 130 can sequentially sample and hold the voltage levels of the reference signal and the image signal provided from the pixel array 110 to each of the plurality of column lines. That is, CDS 130 can sample and hold the voltage levels of the reference signal and the image signal corresponding to each column of the pixel array 110.

[0031] In some implementations, CDS130 can transmit the reference signal and image signal of each column as correlated double-sampled signals to ADC 140 based on control signals from timing controller 170.

[0032] ADC 140 is used to convert analog CDS signals into digital signals. In some implementations, ADC 140 can generate digital signals by comparing analog signals with a reference signal such as a ramp signal. Such an ADC may include comparator circuitry and a timer. The comparator can compare the analog pixel signal with a reference signal such as a ramp signal that is rising or falling, and the timer counts until the voltage of the ramp signal matches the analog pixel signal. In some embodiments of the disclosed technology, ADC 140 can convert the correlated double-sampled signal generated by CDS 130 for each column into a digital signal and output the digital signal. ADC 140 can perform counting and calculation operations based on the correlated double-sampled signal for each column and the ramp signal provided from timing controller 170. In this way, ADC 140 can eliminate or reduce noise such as reset noise generated from imaging pixels when generating digital image data.

[0033] The ADC 140 may include multiple column counters. Each column of the pixel array 110 is coupled to a column counter, and image data (IDATA) and noise data (NDATA) can be generated by converting the correlated double-sampled signals received from each column into digital signals using the column counters. In another embodiment of the disclosed technology, the ADC 140 may include a global counter to convert the correlated double-sampled signals corresponding to a column into digital signals using a global code provided from the global counter. Here, the image data (IDATA) may include digital signals generated from pixel signals generated by active pixels, and the noise data (NDATA) may include digital signals generated from pixel signals generated by optical black pixels.

[0034] Output buffer 150 can temporarily hold column-based image data (IDATA) and noise data (NDATA) provided from ADC 140 for output image data. In one example, the image data (IDATA) and noise data (NDATA) provided to output buffer 150 from ADC 140 can be temporarily stored in output buffer 150 based on control signals from timing controller 170. Output buffer 150 can provide an interface to compensate for data rate or transmission rate differences between image sensing device 100 and other devices.

[0035] Once a control signal is received from the timing controller 170, the column driver 160 can select a column of the output buffer and sequentially output the image data (IDATA) and noise data (NDATA) temporarily stored in the selected column of the output buffer 150. In some implementations, once an address signal is received from the timing controller 170, the column driver 160 can generate a column selection signal based on the address signal and select a column of the output buffer 150, so that the image data (IDATA) and noise data (NDATA) from the selected column of the output buffer 150 can be output as an output signal to the image signal processor 200.

[0036] In some implementations, the readout block is configured to convert pixel signals into digital signals and store or output the digital signals. In one example, the readout block may include a CDS130, an ADC140, an output buffer150, and a column driver160.

[0037] The timing controller 170 can control the operation of the row driver 120, ADC 140, output buffer 150, column driver 160, temperature sensor 180 and base information storage 190.

[0038] The timing controller 170 can provide clock signals, control signals for timing control, and address signals for selecting rows or columns to circuits in the imaging device 10, such as row driver 120, CDS 130, ADC 140, column driver 160, output buffer 150, temperature sensor 180, and base information storage 190. In embodiments of the disclosed technology, the timing controller 170 may include logic control circuitry, phase-locked loop (PLL) circuitry, timing control circuitry, communication interface circuitry, etc.

[0039] In some implementations, the timing controller 170 may receive temperature information from the temperature sensor 180 in response to a sensor control signal (SCS) from the image signal processor 200, and may read base information (PI) corresponding to the received temperature information from the base information storage 190. In one example, the temperature information may indicate the temperature measured by the temperature sensor 180. The timing controller 170 may send the base information (PI) to the image signal processor 200 in response to the sensor control signal (SCS). The base information (PI) may include values ​​for base calibration operations performed by the image signal processor 200.

[0040] Image data (IDATA) may include dark noise components caused by dark currents generated by pixels when they are not exposed to any incident light. Dark currents can be generated due to the structural characteristics of the image sensor and / or the surrounding conditions of the image sensor, rather than by incident light. For example, dangling bonds of silicon atoms with four valence electrons at the surface of a substrate can bond to moving positive charges that are not generated by incident light but are part of a dark current. More specifically, charges created by things other than interacting with incident light are transferred via dark currents to the sensing area of ​​each pixel (e.g., a floating diffusion (FD) area), such that dark noise components (noise independent of incident light) may be included in the image data (IDATA). Since dark noise components have an adverse effect on image quality, they should be removed using noise data (NDATA) generated from optically black (OB) pixels with structures for blocking incident light.

[0041] The disclosed techniques can be implemented in some embodiments to provide noise data (NDATA) with the same value as the dark noise component of the image data (IDATA), thereby removing the dark noise component of the image data (IDATA) more completely.

[0042] Figure 2 This is a graph illustrating an example of the increase in dark current (e- / s; electron charge per second) in active pixels and optical black (OB) pixels due to increased temperature.

[0043] The dark current of active pixels can indicate the dark noise component of image data (IDATA), and the dark current of optical black pixels can indicate noise data (NDATA). (See reference...) Figure 2 The dark current of active pixels differs from that of optical black pixels. As the junction temperature of the substrate on which the pixels are formed increases (e.g., from 60°C to 90°C), the difference between the dark current of active pixels and that of optical black pixels can also increase.

[0044] When removing the dark noise component of image data (IDATA) using noise data (NDATA) without considering the aforementioned differences in dark current, there is a possibility that the dark noise component of the image data (IDATA) may not be sufficiently removed. Therefore, in some embodiments of the disclosed technology, pedestal correction is performed so that the noise data (NDATA) is corrected to have a level equal to the level of the dark noise component of the image data (IDATA). In this way, the corrected noise data (NDATA) accurately reflects the dark noise component in the image data (IDATA) and can therefore be used to remove dark noise from the image data.

[0045] Return to reference Figure 1 Base calibration can be performed using base information (PI) corresponding to a specific temperature. The base information (PI) can contain different values ​​that can be mapped to different temperatures, allowing noise data (NDATA) to be corrected based on the corresponding temperature, so that the corrected noise data (NDATA) accurately reflects the dark noise component of the image data (IDATA). In some implementations, the base information (PI) for a particular image sensor can change with temperature and can include base calibration values ​​that can be used to correct the noise data (NDATA) based on temperature. In some implementations, the timing controller 170 can read the base information (PI) stored in association with temperature information from the base information storage 190 and can send the read base information (PI) to the image signal processor 200.

[0046] In some implementations, the pedestal information (PI) may include a pedestal correction value determined independently for each color (e.g., R / G / B color) of the active pixel. Structural differences may exist between active pixels that include one color filter and pixels that include another color filter (e.g., filters of different colors or different types of color filters may have different structures). Therefore, the difference between the dark current of an active pixel and the dark current of an optical black pixel of the same color may vary even at the same temperature. In some embodiments, the disclosed techniques can be implemented to perform pedestal correction using pedestal correction values ​​determined independently for each color, enabling more accurate removal of dark noise components from image data (IDATA). In some implementations, the temperature may include the temperature of the substrate in which the pixel array 110 is arranged.

[0047] Return to reference Figure 1Temperature sensor 180 can measure the temperature of image sensing device 100 based on commands and control signals from timing controller 170. Temperature sensor 180 can generate temperature information including the measured temperature and can send the generated temperature information to timing controller 170. In some implementations, temperature sensor 180 can measure the temperature of a substrate in which pixel array 110 is disposed.

[0048] The pedestal information storage 190 can store pedestal information (PI) corresponding to each of a plurality of temperatures. In some implementations, pedestal correction is performed when a portion of the substrate is within the plurality of temperatures. In some implementations, the pedestal information (PI) corresponding to each temperature may include pedestal correction values ​​for each color. The pedestal information (PI) can be determined experimentally during a test operation. The pedestal information storage 190 may use a memory device, such as an one-time programmable (OTP) memory, to store the pedestal information (PI).

[0049] although Figure 1 The temperature sensor 180 and the base information storage 190 are illustrated as being included in the image sensing device 100, but at least one of the temperature sensor 180 and the base information storage 190 may also be located outside the image sensing device 100. For example, at least one of the temperature sensor 180 and the base information storage 190 may also be included in the image signal processor 200.

[0050] The image signal processor 200 can process image data (IDATA) received from the image sensing device 100, and can control the image sensing device 100 based on the output signal of the image signal processor 200 or other commands and / or control signals received from external devices.

[0051] Image signal processor 200 can reduce noise in image data (IDATA) and perform image signal processing operations (e.g., gamma correction, color filter array interpolation, color matrix, color correction, color enhancement, etc.) on the image data (IDATA) to improve the image quality of the image data (IDATA). Furthermore, image signal processor 200 can compress the image data (IDATA) created through image signal processing operations, allowing image signal processor 500 to create image files using the compressed image data. Alternatively, image signal processor 200 can recover image data (IDATA) from an image file. Here, reversible or irreversible compression techniques can be used to compress the image data (IDATA). In one example, still images can have compressed image file formats such as the Joint Picture Experts Group (JPEG) format or the JPEG2000 format. In one example, moving images can have compressed video file formats such as the Moving Picture Experts Group (MPEG) standard, allowing moving image files to be created by compressing multiple frames. In another example, image files can be created according to the Exif (Exchangeable Image File Format) standard.

[0052] Image data (IDATA) generated from the image signal processor 200 can be stored in the internal or external memory of the imaging device 10 in response to a user request or independently, so that still images or videos corresponding to the stored image data (IDATA) can be viewed through a display device.

[0053] In addition, the image signal processor 500 can perform operations for removing unclear or blurry parts from images or videos, edge enhancement processing, image analysis processing, image recognition processing, image effect processing, or other operations for improving image quality.

[0054] Furthermore, the image signal processor 200 can perform display image signal processing operations for display purposes. For example, the image signal processor 200 can perform brightness level adjustment, color correction, contrast adjustment, contour emphasis adjustment, screen segmentation processing, feature image generation, and image compositing processing.

[0055] The image signal processor 200 may include a base correction unit 210 and a noise removal unit 220.

[0056] The base calibration unit 210 can request base information (PI) from the image sensing device 100 using a sensor control signal (SCS), and can receive base information (PI) corresponding to the current temperature from the image sensing device 100.

[0057] The pedestal information (PI) may include a pedestal correction value as correction information for correcting the noise data (NDATA) in a manner that adjusts the noise data (NDATA) to a data level or data value equal to the dark noise component (or noise data NDATA) of the image data (IDATA) and the corrected noise data (NDATA) can indicate the dark noise component of the image data (IDATA). The pedestal correction value may include a ratio (e.g., 1.8) between the dark current of an active pixel corresponding to a specific color (e.g., red) at a specific temperature (e.g., 80°) and the dark current of an optical black pixel corresponding to the same color (e.g., red) at a specific temperature (e.g., 80°). The pedestal correction unit 210 may calculate a pedestal correction value (e.g., 1.8) corresponding to the same color (e.g., red) for the noise data (NDATA) corresponding to the specific color (e.g., red), and may perform pedestal correction, wherein the noise data (NDATA) is adjusted to a data level equal to the dark noise component of the image data (IDATA). For example, the calculation (or operation) described above could be a calculation (or operation) of multiplying the pedestal correction value by the noise data (NDATA), or it could be another implementation. Additionally, pedestal correction can be performed independently for each color.

[0058] The noise removal unit 220 can receive pedestal-corrected noise data for each color from the pedestal correction unit 210, and use the pedestal-corrected noise data corresponding to a specific color (e.g., red) to remove the dark noise component of the image data (IDATA) corresponding to the same color (e.g., red). In some implementations, the dark noise component of the image data (IDATA) can be removed by subtracting the pedestal-corrected noise data from the image data (IDATA).

[0059] Figure 3 These are examples of some implementations based on the disclosed technology. Figure 1 A block diagram of an example of pixel array 110 shown.

[0060] Reference Figure 3 The pixel array 110 may include an active pixel array 310, an optical black (OB) pixel array 320, an active test block 330, and an optical black (OB) test block 340.

[0061] In this implementation, the optical black (OB) pixel array 320 is arranged along one side of the pixel array 110, while the active pixel array 310 is arranged along the other side of the pixel array 110. The optical black (OB) test block 340 and the active test block 330 are arranged between the optical black (OB) pixel array 320 and the active pixel array 310.

[0062] The active test block 330 can be disposed on one side (e.g., the lower side) of the active pixel array 310, and the optical black (OB) test block 340 can be disposed on the other side (e.g., the upper side) of the optical black (OB) pixel array 320.

[0063] The structure, location, and size of the active pixel array 310, the optical black (OB) pixel array 320, the active test block 330, and the optical black (OB) test block 340 are discussed by way of example only.

[0064] The active pixel array 310 may include active pixels as a main image sensing pixel array. The active pixels are configured to be exposed to incident light and convert the received incident light into electrical signals such as pixel signals to capture an image in the incident light.

[0065] The optical black (OB) pixel array 320 may include optical black (OB) pixels configured to be shielded from incident light, such that incident light cannot reach the pixels in the OB pixel array 320 and the pixels in the OB pixel array 320 generate pixel signals representing the pixel response in the absence of incident light.

[0066] The active test block 330 may include active pixels (or first image sensing pixels) having the same or similar structure as the active pixels in the active pixel array 310. The active test block 330 may also include additional structures for controlling the temperature of the active pixels in the active test block 330. The active test block 330 can be used to obtain measurements of the dark current of the active pixels in the active test block 330 for each color at a set temperature during test operation of the image sensing device.

[0067] The optical black (OB) test block 340 may include optical black (OB) pixels (or second image sensing pixels) and structures for controlling the temperature of the optical black (OB) pixels. The optical black (OB) test block 340 can be used to obtain the dark current of the optical black (OB) pixels for each color at a set temperature during a test operation.

[0068] The active test block 330 will be referred to below as the first test block, and the optical black (OB) test block 340 will be referred to below as the second test block.

[0069] Figure 4A These are examples of some implementations based on the disclosed technology. Figure 3 A schematic diagram of an example of an active test block is shown. Figure 4B These are examples of some implementations based on the disclosed technology. Figure 4A The cross-sectional view of an example of an active test block cut by the first cutting line is shown.

[0070] Reference Figure 4A The active test block 330 may include multiple active pixels (AP) and a first heating element (HE1).

[0071] Multiple active pixels (APs) can be arranged in a matrix array. Although Figure 4A An example is shown, consisting of a 6x6 matrix array with six rows and six columns, but the number of rows and columns can vary. In some implementations, each active pixel (AP) can be... Figure 3 The active pixels included in the pixel array 310 shown have essentially the same structure.

[0072] A first heating element (HE1) can be used to control the temperature of multiple active pixels (APs) in response to a heating control signal from a test apparatus (not shown) during test operation. The first heating element (HE1) can generate heat corresponding to the heating control signal and transfer the heat to the multiple active pixels (APs). That is, the first heating element (HE1) can set the temperature of the active pixels (APs) to a temperature corresponding to the heating control signal. For this purpose, the image sensing device 100 may include a terminal (not shown) configured to receive a heating control signal from the test apparatus. Here, the terminal may be electrically connected to the first heating element (HE1) to send the heating control signal to the first heating element (HE1).

[0073] In one implementation, the first heating element (HE1) may be arranged to surround or enclose a plurality of active pixels (APs) and configured to transfer heat to the plurality of active pixels (APs). In another implementation, the first heating element (HE1) may include any shape configured to transfer heat to the plurality of active pixels (APs).

[0074] Figure 4B It is based on some implementations of the disclosed technology along... Figure 4A The image shows a cross-sectional view of the active test block 330 taken by the first cutting line AA′. From... Figure 4B As shown in the cross-sectional view of the active test block 330, the active test block 330 may include: a substrate 332; an array of active pixels AP supported by the substrate, wherein each active pixel AP is operable to generate a charge in response to incident light; an optical grating structure 334 supported by the substrate 332, which divides the space above the substrate 332 into periodic regions overlapping with the array of active pixels AP; an array of filters 336 corresponding to the array of APs to filter incident light to the APs respectively; an array of microlenses 338 corresponding to the array of APs to guide incident light to the APs respectively; and a first heating element (HE1).

[0075] Substrate 332 may include a top surface and a bottom surface. Although for ease of description, the top surface of substrate 332 may be defined as the front side and the bottom surface of substrate 332 as the back side. For example, substrate 332 may include a P-type or N-type body substrate, a substrate formed by growing a P-type or N-type epitaxial layer on a P-type body substrate, or a substrate formed by growing a P-type or N-type epitaxial layer on an N-type body substrate. Substrate 332 may include P-type or N-type doped regions 333 having P-type or N-type conductive impurities.

[0076] P-type or N-type doped region 333 may include a photoelectric conversion region (not shown) disposed in the region of the substrate 332 corresponding to the active pixel AP. The photoelectric conversion region can be formed as an N-type doped region by ion implantation of N-type ions. In some implementations, the photoelectric conversion region can be formed by stacking multiple doped regions. In some implementations, the lower doped region can be formed by implanting N+ ions, and the upper doped region can be formed by implanting N- ions. The photoelectric conversion region can be configured to have a fill factor large enough to increase or maximize the indicated light receiving (Rx) efficiency. In some implementations, a device isolation layer (not shown) disposed between the photoelectric conversion regions of adjacent active pixels (APs) can be formed by performing an etching process in the vertical direction, such that the device isolation layer enables electrical or optical isolation between adjacent pixels.

[0077] The photoelectric conversion region can generate and accumulate photocharge corresponding to the intensity of incident light. The photocharge accumulated in the photoelectric conversion region can be converted into a pixel signal corresponding to an electrical signal by a separate pixel signal circuit. For example, the pixel signal circuit may include a transfer (Tx) transistor of a 4-transistor (4T) pixel, a floating diffusion region, a reset transistor, a source follower transistor, and a select transistor.

[0078] The optical grating structure 334 prevents optical crosstalk between adjacent active pixels (APs). That is, the optical grating structure 334 prevents light incident on the filter 336 of one active pixel (AP) from propagating towards the filter 336 of another adjacent active pixel (AP). For this purpose, the optical grating structure 334 can be disposed along the boundary between adjacent active pixels (APs) and can include a shielding material that can be used to block light. For example, the optical grating structure 334 can include tungsten (W) with a high light absorption rate.

[0079] A filter 336 may be formed above the substrate 332 and may selectively transmit light signals of a specific wavelength (e.g., red, green, blue, magenta, yellow, cyan). Each active pixel (AP) may be distinguished by the color of its filter 336. For example, a "red" active pixel (AP) may include a "red" optical filter that allows only red light to pass through, a "green" active pixel (AP) may include a "green" optical filter 336 that allows only green light to pass through, and a "blue" active pixel (AP) may include a "blue" optical filter 336 that allows only blue light to pass through.

[0080] Microlens 338 can be formed above filter 336 and can increase the focusing ability of incident light, thereby increasing the light receiving (Rx) efficiency of the photoelectric conversion region included in each active pixel (AP). Although Figure 4B The example illustrates that each active pixel AP includes one microlens 338, but each active pixel AP may include more than one microlens or may not include a microlens. For example, multiple phase detection autofocus (PDAF) pixels may share a single microlens.

[0081] The first heating element (HE1) can be disposed on the left and right sides of the six active pixels (AP). The first heating element (HE1) can be disposed in the substrate 332 to transfer heat to the doped region 333 in which dark current is generated.

[0082] In some implementations, each first heating element (HE1) may include a thermoelectric element configured to absorb heat on one surface and generate heat on the other surface based on the Peltier effect, depending on the direction of the current generated when a voltage is applied across the two ends of the element. Thus, each first heating element (HE1) may include an absorbing surface and a heating surface. The heating surface may be positioned close to the active pixel (AP) to more efficiently transfer heat to the active pixel (AP). For example, the left surface of a first heating element (HE1) located on the left side of the active test block 330 may be an absorbing surface, and the right surface of a first heating element (HE1) located on the right side of the active test block 330 may be a heating surface.

[0083] The first heating element (HE1) can generate heat corresponding to a heating control signal and transfer the heat to multiple active pixels (APs). When the first heating element (HE1) includes a thermoelectric element, the heating control signal can include a voltage applied to both ends of the first heating element (HE1). Here, the voltage applied to one end of the first heating element (HE1) can be different from the voltage applied to the other end of the first heating element (HE1), and the voltage difference between the two voltages can be predetermined, so that the heat-absorbing surface and the heating surface of the first heating element (HE1) can be fixed.

[0084] Furthermore, the voltage difference applied across the first heating element (HE1) determines the current flowing in the first heating element (HE1). For example, as the current flowing in the first heating element (HE1) increases, the heat generated from the heating surface can also increase. As the current flowing in the first heating element (HE1) decreases, the heat generated from the heating surface can also decrease. That is, the test apparatus (not shown) can control the temperature of the first heating element (HE1) by controlling the heating control signal. Subsequently, as the first heating element (HE1) and the active pixels (AP) reach thermal equilibrium, the temperature of multiple active pixels (APs) can be controlled.

[0085] Figure 5A These are examples of some implementations based on the disclosed technology. Figure 3 A schematic diagram of an example of an optical black (OB) test block. Figure 5B These are examples of some implementations based on the disclosed technology. Figure 5A The cross-sectional view of an example optical black (OB) test block cut by the second cutting line is shown.

[0086] Reference Figure 5A The optical black (OB) test block 340 may include multiple optical black pixels (OBP) and a second heating element (HE2).

[0087] Multiple optical black pixels (OBPs) can be arranged in a matrix array. Although Figure 5A An example is shown where optical black pixels (OBPs) are arranged in a 6×6 matrix array comprising six rows and six columns, but the number of rows and columns can vary. In some implementations, each optical black pixel (OBP) can be structurally associated with elements included in... Figure 3 The optical black pixels in the optical black pixel array 320 shown are basically the same.

[0088] The second heating element (HE2) can be used to control the temperature of multiple optical black pixels (OBPs) in response to a heating control signal from a test apparatus (not shown) during test operation. The second heating element (HE2) can generate heat corresponding to the heating control signal and can transfer the generated heat to the multiple optical black pixels (OBPs). That is, the second heating element (HE2) can set the temperature of the optical black pixels (OBPs) to a temperature corresponding to the heating control signal. For this purpose, the image sensing device 100 may include a terminal (not shown) configured to receive a heating control signal from the test apparatus. The terminal can be electrically connected to the second heating element (HE2) so that the heating control signal can be sent to the second heating element (HE2) through the terminal.

[0089] In one implementation, the second heating element (HE2) can be arranged to surround or enclose a plurality of optical black pixels (OBPs) and configured to transfer heat to the optical black pixels (OBPs). In another implementation, the second heating element (HE2) can include any shape configured to transfer heat to the plurality of optical black pixels (OBPs).

[0090] Figure 5B These are examples of some implementations based on the disclosed technology. Figure 5A The image shows a cross-sectional view of the optical black test block 340 taken by the second cutting line BB′. From... Figure 5B As can be seen from the cross-sectional view of the optical black test block 340 shown, the optical black test block 340 may include a substrate 342, a light blocking structure 344, a filter 346, a microlens 348, and a second heating element (HE2).

[0091] In some implementations, Figure 5B The substrate 342 and microlens 348 shown can be used with Figure 4B The substrate 332 and microlens 338 shown have the same or similar structures.

[0092] and Figure 4B The optical grating structure shown is different from 334. Figure 5B The light blocking structure 344 shown can be disposed above the entire area of ​​the optical black pixel (OBP) so that the light blocking structure 344 is shielded from light incident on it and the light is not transmitted to the substrate 342.

[0093] The light-blocking structure 344 may include a shielding material that can be used to block light. For example, the light-blocking structure 344 may include tungsten (W) with a high light absorption rate. The light-blocking structure can be formed using the same process as the optical grating structure 334.

[0094] and Figure 4B Unlike the filter 336 shown, filter 346 can be disposed above the light-blocking structure 344, rather than in the area between adjacent optical grid structures 334. Each optical black pixel (OBP) can be identified by the filter 346 it includes. For example, a "red" optical black pixel (OBP) includes a "red" optical filter 346 that allows only red light to pass through, a "green" optical black pixel (OBP) includes a "green" optical filter 346 that allows only green light to pass through, and a "blue" optical black pixel (OBP) includes a "blue" optical filter 346 that allows only blue light to pass through.

[0095] The remaining components of filter 346 may have the same or similar structure as the remaining components of filter 336.

[0096] The second heating element (HE2) can be disposed on the left and right sides of the six optical black pixels (OBP). The second heating element (HE2) can be disposed in the substrate 342 to transfer heat to the doped region 343 where dark current is generated.

[0097] In some implementations, each second heating element (HE2) may include a thermoelectric element. In this case, each second heating element (HE2) may include a heat-absorbing surface and a heating surface. The heating surface may be positioned towards the optical black pixel (OBP) so that heat can be effectively transferred to the optical black pixel (OBP). For example, the left surface of the second heating element (HE2) located on the left side of the optical black test block 340 may be a heat-absorbing surface, and the right surface of the second heating element (HE2) located on the right side of the optical black test block 340 may be a heating surface.

[0098] The second heating element (HE2) can generate heat corresponding to the heating control signal and transfer the heat to multiple optical black pixels (OBPs). When the second heating element (HE2) includes a thermoelectric element, the heating control signal can include a voltage applied to both ends of the second heating element (HE2). Here, the voltage applied to one end of the second heating element (HE2) can be different from the voltage applied to the other end of the second heating element (HE2), and the voltage difference between the two voltages can be predetermined, so that the heat-absorbing surface and the heating surface of the second heating element (HE2) can be fixed.

[0099] Furthermore, the voltage difference applied across the second heating element (HE2) determines the current flowing in the second heating element (HE2). For example, as the current flowing in the second heating element (HE2) increases, the heat generated from the heating surface can also increase. As the current flowing in the second heating element (HE2) decreases, the heat generated from the heating surface can also decrease. That is, the test apparatus (not shown) can control the temperature of the second heating element (HE2) by controlling the heating control signal. Subsequently, as the second heating element (HE2) and the optical black pixels (OBP) reach thermal equilibrium, the temperature of multiple optical black pixels (OBPs) can be controlled.

[0100] Figure 6 This is a flowchart illustrating examples of methods for obtaining base information based on some implementations of the disclosed technology.

[0101] Reference Figure 6 The image sensing device 100 can be included in a chip and can be executed in the processing of the test chip. Figure 6 The corresponding operations S100-S150 are shown. Furthermore, each of operations S100-S150 can be performed under dark conditions where light is completely blocked.

[0102] This is because each of operations S100 to S150 corresponds to an operation that obtains pedestal information (PI) indicating the ratio between the dark current of the active pixel (AP) and the dark current of the optical black pixel (OBP) in the case of generating the dark current of the pixels AP and OBP independently of light.

[0103] The testing apparatus (not shown) can generate a heating control signal corresponding to a set temperature (e.g., 60°C) and can send the heating control signal to each of the first heating element (HE1) and the second heating element (HE2). Each of the first heating element (HE1) and the second heating element (HE2) can be heated to the set temperature corresponding to the heating control signal. The heated first heating element (HE1) can reach thermal equilibrium with the active pixel (AP) in the same manner, and the heated second heating element (HE2) can reach thermal equilibrium with the optical black pixel (OBP) in the same manner. Therefore, the temperature of each active pixel (AP) can be the same as the set temperature, and the temperature of each optical black pixel (OBP) can be the same as the set temperature (S100).

[0104] Each active pixel (AP) of the active test block 330 with a set temperature can generate a pixel signal, and the pixel signal of each active pixel (AP) can be converted into a digital value after passing through CDS 130, ADC 140, and output buffer 150. In some implementations, the active pixels (APs) may include red active pixels, green active pixels, and blue active pixels. In this case, the test apparatus can calculate red active test data by calculating the digital value corresponding to the red active pixel (e.g., calculating the average value), calculate green active test data by calculating the digital value corresponding to the green active pixel (e.g., calculating the average value), and calculate blue active test data by calculating the digital value corresponding to the blue active pixel (e.g., calculating the average value).

[0105] Red active test data can refer to the dark noise component caused by the dark current generated in red active pixels at a set temperature. Green active test data can refer to the dark noise component caused by the dark current generated in green active pixels at a set temperature. Blue active test data can refer to the dark noise component caused by the dark current generated in blue active pixels at a set temperature. In this case, the red active test data, green active test data, and blue active test data can be collectively referred to as the first test data (S110).

[0106] Each optical black pixel (OBP) of the optical black test block 340 with a set temperature can generate a pixel signal, and the pixel signal of each active pixel (OBP) can be converted into a digital value after passing through CDS 130, ADC 140, and output buffer 150. In some implementations, the optical black pixels (OBP) may include red optical black pixels, green optical black pixels, and blue optical black pixels. In this case, the test apparatus can calculate red optical black test data by calculating the digital value corresponding to the red optical black pixel (e.g., calculating the average value), calculate green optical black test data by calculating the digital value corresponding to the green optical black pixel (e.g., calculating the average value), and calculate blue optical black test data by calculating the digital value corresponding to the blue optical black pixel (e.g., calculating the average value).

[0107] Red optical black test data can refer to the dark noise component caused by the dark current generated by the red optical black pixel at a set temperature. Green optical black test data can refer to the dark noise component caused by the dark current generated by the green optical black pixel at a set temperature. Blue optical black test data can refer to the dark noise component caused by the dark current generated by the blue optical black pixel at a set temperature. In this case, the red optical black test data, green optical black test data, and blue optical black test data can be collectively referred to as the second test data (S120).

[0108] The testing apparatus can generate base information (PI) for a set temperature based on the first test data and the second test data (S130). Therefore, the base information (PI) can refer to information related to the pixel signals of the active pixel (AP) and the pixel signals of the optical black pixel (OBP).

[0109] In some implementations, the testing apparatus can determine a specific value obtained by dividing the red active pixel test data in the first test data by the red optical black pixel test data in the second test data as the red base correction value for a set temperature. In other words, the red base correction value for a set temperature can refer to the ratio of the dark noise component caused by the dark current of the red active pixel to the dark noise component caused by the dark current of the red optical black pixel at the set temperature.

[0110] Furthermore, the testing apparatus can determine a specific value obtained by dividing the green active pixel test data in the first test data by the green optical black pixel test data in the second test data as the green substrate correction value for a set temperature. In other words, the green substrate correction value for a set temperature can refer to the ratio of the dark noise component caused by the dark current of the green active pixel to the dark noise component caused by the dark current of the green optical black pixel at the set temperature.

[0111] In some implementations, the testing apparatus can determine a specific value obtained by dividing the blue active pixel test data in the first test data by the blue optical black pixel test data in the second test data as the blue substrate correction value for a set temperature. In other words, the blue substrate correction value for a set temperature can refer to the ratio of the dark noise component caused by the dark current of the blue active pixel to the dark noise component caused by the dark current of the blue optical black pixel at the set temperature.

[0112] The testing device can allow the base information (PI) including all red base correction values, green base correction values ​​and blue base correction values ​​to be matched with the set temperature, and therefore the base information (PI) matched with the set temperature can be stored in the base information storage 190 (S140).

[0113] The testing device can change a set temperature (e.g., 60°C) to a new set temperature (e.g., 61°C) (S150), and can perform operations S110-S140 for acquiring and storing base information (PI) corresponding to the changed set temperature (e.g., 61°C). In this case, the operation of changing the set temperature (e.g., increasing the set temperature) may refer to the operation of changing the heating control signal (e.g., increasing the voltage difference).

[0114] Additionally, the testing device can repeatedly execute operations S110-S140 for acquiring and storing base information (PI) corresponding to a set temperature until base information (PI) corresponding to each temperature required for base calibration is acquired and stored. Multiple temperatures can be determined at preset temperature intervals within any temperature range (e.g., 40°C-100°C), or can be randomly determined within any temperature range (e.g., 40°C-100°C).

[0115] When completed Figure 6 During the operation shown, the base information (PI) corresponding to each temperature required for base calibration can be stored in the base information storage 190.

[0116] In addition, although Figure 6 Each of operations S100 to S140 is illustrated as being performed only once at a specific temperature, but other implementations are also possible, and it should be noted that each of operations S100 to S140 may also be performed several times at each temperature required for base calibration to improve the accuracy of base information (PI).

[0117] Figure 7 This is a flowchart illustrating an example of a method for performing base calibration using base information (PI) based on some implementations of the disclosed technology.

[0118] The following will refer to Figure 7Describes a method for forming a scene image captured by an imaging device 100, which has already performed... Figure 6 The image sensing device 100 is used for testing operations.

[0119] The image signal processor 200 can generate a sensor control signal (SCS) requesting image formation and can send the sensor control signal (SCS) to the image sensing device 100. The timing controller 170 of the image sensing device 100, having received the sensor control signal (SCS), can drive each of the active pixel array 310 and the optical black pixel array 320, thereby generating image data (IDATA) and noise data (NDATA). The image signal processor 200 can acquire image data (IDATA) from the image sensing device 100 (S200) and can acquire noise data (NDATA) from the image sensing device 100 (S210).

[0120] The image signal processor 200 can generate a sensor control signal (SCS) requesting substrate information (PI) and can send the generated sensor control signal (SCS) to the image sensing device 100. The timing controller 170 of the image sensing device 100, having received the sensor control signal (SCS), can control the temperature sensor 180 to obtain the current temperature of the substrate on which the pixel array 110 is formed.

[0121] Temperature sensor 180 can measure the temperature of each of a plurality of locations placed in the substrate on which pixel array 110 is formed, and can determine the average of the measured temperatures as the current temperature. Temperature sensor 180 can measure the temperature of at least one of active pixel array 310 and optical black pixel array 320, and can therefore determine the current temperature based on the measured temperature.

[0122] In some implementations, the sensor control signal (SCS) used to request pedestal information (PI) may be the same as or different from the sensor control signal (SCS) used to request image generation.

[0123] The timing controller 170 can read the base information (PI) corresponding to the current temperature from the base information storage 190 by referring to information in the base information storage 190, which is configured to store base information (PI) corresponding to each of a plurality of temperatures. The image signal processor 200 can obtain the base information (PI) corresponding to the current temperature from the image sensing device 100 (S220). In some implementations, the base information (PI) may include a red base correction value, a green base correction value, and a blue base correction value.

[0124] In this case, the base information (PI) corresponding to the current temperature can refer to the base information (PI) corresponding to the temperature among multiple temperatures that is equal to or closest to the current temperature.

[0125] The pedestal correction unit 210 of the image signal processor 200 can calculate a pedestal correction value (e.g., red pedestal correction value) corresponding to the same color (e.g., red) for noise data (NDATA) corresponding to a specific color (e.g., red), and can perform pedestal correction (S230) for correcting noise data (NDATA) in a manner that adjusts the corrected noise data (NDATA) to a data level equal to the dark noise component of the image data (IDATA). For example, this operation could refer to multiplying the pedestal correction value by the noise data (NDATA), and other implementations are also possible.

[0126] The noise removal unit 220 of the image signal processor 200 can receive pedestal-corrected noise data for each color from the pedestal correction unit 210, calculate pedestal-corrected noise data corresponding to the same color (e.g., red) as the image data (IDATA) corresponding to a specific color (e.g., red), and remove the dark noise component of the image data (IDATA) based on the calculated pedestal-corrected noise data (S240). Here, this operation may refer to the operation of subtracting the pedestal-corrected noise data from the image data (IDATA), and other implementations are also possible.

[0127] Imaging apparatus 10 based on some implementations of the disclosed technology can enable the chip (i.e., image sensing device 100) to include test blocks for generating pedestal information (PI), can store independent pedestal information (PI) for each chip, and can perform pedestal correction using the stored pedestal information (PI). As a result, imaging apparatus 10 is able to remove dark noise components contained in image data (IDATA) more accurately.

[0128] Furthermore, the image sensing device 100 can store base information (PI) for each subdivision temperature, and can use the stored base information (PI) to perform base correction, enabling the image sensing device 100 to more accurately remove dark noise components contained in the image data (IDATA).

[0129] As is evident from the above description, some implementations of the disclosed technology of an image sensing device may include a test block for generating pedestal information, which allows each image sensor semiconductor chip to store independent pedestal information, thereby performing pedestal correction on a chip-by-chip basis. This enables a more accurate reflection of the dark noise components contained in the image data during image correction.

[0130] Although numerous exemplary embodiments have been described, it should be understood that various modifications, enhancements, and other embodiments of the disclosed embodiments can be designed based on the descriptions and / or examples in this patent document.

[0131] Cross-reference to related applications

[0132] This patent document claims priority and benefit to Korean Patent Application No. 10-2021-0084888, filed on June 29, 2021, the disclosure of which is incorporated herein by reference in its entirety as part of the disclosure of this patent document.

Claims

1. An image sensing device comprising: a first test block including a plurality of first image sensing pixels configured to convert incident light carrying an image into first pixel signals indicative of the image, and a first heating element configured to deliver heat to the first image sensing pixels; a second test block including a plurality of second image sensing pixels each including a light-blocking structure to be shielded from receiving incident light to generate second pixel signals without being directly exposed to the incident light, and a second heating element configured to deliver heat to the second image sensing pixels; an active pixel array disposed adjacent to the first test block and including a plurality of active image sensing pixels each having a structure corresponding to the first image sensing pixels; an optical black pixel array disposed adjacent to the second test block and including a plurality of optical black pixels each having a structure corresponding to the second image sensing pixels; a readout block processing the first pixel signals output from the first test block and the second pixel signals output from the second test block; and a pedestal information storage circuit storing pedestal information related to the first pixel signals of the first image sensing pixels and the second pixel signals of the second image sensing pixels, wherein the readout block generates image data by processing pixel signals output from the active pixel array, and generates noise data by processing pixel signals output from the optical black pixel array, wherein the pedestal information is used to correct the noise data such that the corrected noise data is indicative of a dark noise component of the image data. 2.The image sensing device according to claim 1, wherein the pedestal information storage circuit stores the pedestal information corresponding to each of a plurality of temperatures. 3.The image sensing device according to claim 1, wherein the pedestal information includes a pedestal correction value corresponding to each color of color filters of the first image sensing pixels in the first test block. 4.The image sensing device according to claim 3, wherein the color filters include a red color filter, a green color filter, and a blue color filter. 5.The image sensing device according to claim 1, wherein the pedestal information is generated based on the first pixel signals of each of the first image sensing pixels included in the first test block and the second pixel signals of each of the second image sensing pixels included in the second test block. 6.The image sensing device according to claim 1, further comprising: a temperature sensor that: measures a temperature of at least one of the active pixel array and the optical black pixel array; and determines a current temperature based on the measured temperature. ​ ​ 7. The image sensing device according to claim 6, further comprising: a timing controller that reads out the pedestal information corresponding to the current temperature from the pedestal information storage circuit.

8. The image sensing device according to claim 1, wherein the first heating element is disposed so as to surround the first image sensing pixels of the first test block.

9. The image sensing device according to claim 1, wherein the second heating element is disposed so as to surround the second image sensing pixels of the second test block.

10. The image sensing device according to claim 1, wherein each of the first heating element and the second heating element is disposed in a substrate that includes a photoelectric conversion region of the first image sensing pixels and a photoelectric conversion region of the second image sensing pixels.

11. The image sensing device according to claim 1, wherein each of the first heating element and the second heating element includes a thermoelectric element.

12. An imaging apparatus comprising: an image sensing device including a plurality of active image sensing pixels configured to convert incident light carrying an image into image data indicative of the image, and a plurality of optical black pixels shielded from the incident light to generate noise data indicative of noise in the image data; and an image signal processor that corrects the noise data using pedestal information corresponding to a temperature of the image sensing device, and subtracts the corrected noise data from the image data, wherein the image sensing device includes: a first test block including a plurality of first image sensing pixels configured to convert the incident light carrying the image into first pixel signals indicative of the image, and a first heating element configured to transfer heat to the first image sensing pixels; a second test block including a plurality of second image sensing pixels including a light blocking structure to be shielded from receiving the incident light to generate second pixel signals without being directly exposed to the incident light, and a second heating element configured to transfer heat to the second image sensing pixels; and a pedestal information storage circuit that stores the pedestal information related to the first pixel signals of the first image sensing pixels and the second pixel signals of the second image sensing pixels.

13. The imaging apparatus of claim 12, wherein, the pedestal information storage circuit stores the pedestal information corresponding to each of a plurality of temperatures.

14. The imaging apparatus of claim 12, wherein, the pedestal information includes a pedestal correction value corresponding to each color of a color filter of the first image sensing pixels.

15. The imaging apparatus of claim 12, wherein, The pedestal information is generated based on the first pixel signal of each of the first image sensing pixels included in the first test block and the second pixel signal of each of the second image sensing pixels included in the second test block.

16. The imaging device of claim 12, wherein, the first heating element is disposed around the first image sensing pixels of the first test block.

17. The imaging device of claim 12, wherein, the second heating element is disposed around the second image sensing pixels of the second test block.

Images