An image sensor, a camera module and an electronic device

Abstract

The application discloses an image sensor, a camera module and an electronic device, and belongs to the technical field of image processing. The image sensor comprises a pixel array, the pixel array comprises at least two first pixel units, the first pixel unit is hexagonal, and the first pixel unit comprises at least four pentagonal sub-pixels.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of image processing, and particularly relates to an image sensor, a camera module and an electronic device. BACKGROUND

[0002] HDR is the abbreviation of High-Dynamic Range, and compared with an ordinary image, an HDR image can provide more dynamic range and image details, and is closer to the image seen by the human eye. The realization of the HDR effect of a mobile phone camera is to take several photos with different exposures at one time, and then automatically synthesize a photo according to an algorithm to achieve the HDR effect. Multi-frame noise reduction is to calculate and screen the number and position of noise points of multiple frames when the mobile phone is shooting a night scene or a dark environment, and to replace the position of the noise points with the frame number without noise points. After repeated weighting and replacement, a photo almost without noise points is obtained, and the final imaging photo is actually synthesized from multiple frame photos.

[0003] However, due to the large exposure difference of the frames captured by the HDR mode, the exposure fusion algorithm is difficult, the multi-frame alignment is difficult, and the image edge is prone to misalignment and image distortion. For moving objects or objects moving in a dark place, ghosting is prone to occur. As for multi-frame noise reduction, the implementation process is similar to that of HDR, so the same problems exist. Therefore, due to the limitations of the shooting hardware and software in the prior art, the photos obtained by shooting inevitably have color deviation and distortion, and the realism of the photos is poor. SUMMARY

[0004] The purpose of the embodiments of the present application is to provide an image sensor, a camera module and an electronic device, which can solve the problem that the photos obtained by shooting inevitably have color deviation and distortion due to the limitations of the shooting hardware and software in the prior art, and the realism of the photos is poor.

[0005] In a first aspect, the embodiments of the present application provide an image sensor, which comprises:

[0006] a pixel array, the pixel array comprising at least two first pixel units, the first pixel unit being hexagonal, and the first pixel unit comprising at least four pentagonal sub-pixels.

[0007] In a second aspect, the embodiments of the present application provide a camera module, which comprises the image sensor according to the first aspect.

[0008] In a third aspect, the embodiments of the present application provide an electronic device, which comprises the camera module according to the second aspect.

[0009] In the embodiment of the present application, the pixel array in the image sensor comprises at least two first pixel units, each of which is hexagonal and comprises at least four pentagonal sub-pixels, so that a plurality of sub-pixels in the pixel unit can output a plurality of light values in a single exposure process, thereby obtaining a plurality of images with different or same exposure values, and then completing HDR synthesis and multi-frame noise reduction function, thereby effectively avoiding the occurrence of image misregistration, trailing and other phenomena, and at the same time, the resolution and light sensitivity of the image sensor can be improved, the dynamic range is expanded, and the imaging quality is improved. BRIEF DESCRIPTION OF DRAWINGS

[0010] Figure 1 One of the schematic diagrams of the first pixel unit provided by the embodiment of the present application;

[0011] Figure 2 One of the schematic diagrams of the pixel array provided by the embodiment of the present application;

[0012] Figure 3 The second schematic diagram of the first pixel unit provided by the embodiment of the present application;

[0013] Figure 4 The second schematic diagram of the pixel array provided by the embodiment of the present application;

[0014] Figure 5 The third schematic diagram of the first pixel unit provided by the embodiment of the present application;

[0015] Figure 6 The third schematic diagram of the pixel array provided by the embodiment of the present application;

[0016] Figure 7 The fourth schematic diagram of the first pixel unit provided by the embodiment of the present application;

[0017] Figure 8 The fourth schematic diagram of the pixel array provided by the embodiment of the present application;

[0018] Figure 9 The fifth schematic diagram of the first pixel unit provided by the embodiment of the present application;

[0019] Figure 10 The fifth schematic diagram of the pixel array provided by the embodiment of the present application;

[0020] Figure 11 The sixth schematic diagram of the first pixel unit provided by the embodiment of the present application;

[0021] Figure 12 The sixth schematic diagram of the pixel array provided by the embodiment of the present application;

[0022] Figure 13 The seventh schematic diagram of the first pixel unit provided by the embodiment of the present application;

[0023] Figure 14 A seventh schematic diagram of a pixel array provided for an embodiment of the present application;

[0024] Figure 15 An eighth schematic diagram of a first pixel unit provided for an embodiment of the present application;

[0025] Figure 16 An eighth schematic diagram of a pixel array provided for an embodiment of the present application;

[0026] Figure 17 One of the schematic diagrams of the red, green and blue three color bands provided for an embodiment of the present application;

[0027] Figure 18 The schematic diagram of the red, green and blue three color bands provided for an embodiment of the present application;

[0028] Figure 19 The schematic diagram of the visible light band divided into 13 sub-bands provided for an embodiment of the present application;

[0029] Figure 20 One of the schematic diagrams of the pixel circuit structure provided for an embodiment of the present application;

[0030] Figure 21 The second schematic diagram of the pixel circuit structure provided for an embodiment of the present application;

[0031] Figure 22 The exploded view of the camera module provided for an embodiment of the present application;

[0032] Figure 23 The structural schematic diagram of the camera module provided for an embodiment of the present application. DETAILED DESCRIPTION

[0033] The technical solutions in the embodiments of the present application will be clearly described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art belong to the scope of protection of the present application.

[0034] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a particular order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described herein, and the objects distinguished by "first", "second", etc. are generally a class, and do not limit the number of objects, for example, the first object can be one or more. In addition, "and / or" in the specification and claims indicates at least one of the connected objects, and the character " / ", generally indicates that the objects before and after are in a "or" relationship.

[0035] In order to facilitate understanding, the related technologies designed by the embodiments of the present application are described first.

[0036] The camera sensor is the core of the camera and the most critical technology in the camera. Sensor is divided into two kinds, one is the widely used CCD (Charge-coupled Device) element; the other is CMOS (Complementary Metal Oxide Semiconductor) device. Compared with traditional cameras, traditional cameras use "film" as the carrier of their recorded information, while the "film" of digital cameras is its imaging photosensitive element, and the photosensitive element is integrated with the camera.

[0037] The CMOS device is currently used more, which is a semiconductor that can record light changes in a digital camera, like the CCD element. CMOS is mainly made of silicon and germanium, two elements of semiconductor, so that N (positive) and P (positive) level semiconductors coexist on CMOS, and the current generated by the two complementary effects can be recorded and interpreted into images by the processing chip.

[0038] The camera lens is the most important part of the camera, and the quality of the lens directly affects the quality of the imaging. The lens can be divided into two categories: zoom and fixed focus. Among them, the zoom lens has variable focal length and variable angle, that is, the lens can be pushed and pulled; while the fixed focus lens has a fixed focal length, that is, it has only one focal length or only one angle of view.

[0039] CMOS camera module is the mainstream camera module used in mobile phones at present, mainly composed of lens, voice coil motor, infrared filter, image sensor (CMOS), digital signal processor (DSP) and flexible printed circuit (FPC).

[0040] The approximate working process of CCM is: the voice coil motor drives the lens to reach the accurate focusing position, the external light passes through the lens, is filtered by the infrared filter, and irradiates on the photodiode of the image sensor, the photodiode converts the perceived light signal into an electrical signal, forms a digital signal matrix (i.e. image) through an amplification circuit and an analog-digital conversion circuit, and is processed by a digital signal processor and compressed for storage.

[0041] The image sensor, camera module and electronic device provided by the embodiments of the present application will be described in detail in combination with the drawings and specific embodiments and application scenarios.

[0042] The image sensor provided by the embodiments of the present application comprises a pixel array, and the pixel array comprises at least two first pixel units. Optionally, the at least two first pixel units can be arranged in a preset arrangement mode, such as row-column arrangement, to form the pixel array. The first pixel unit is hexagonal, and the first pixel unit comprises at least four pentagonal sub-pixels, that is, the plurality of sub-pixels included in the first pixel unit are in a multi-in-one form and jointly constitute the hexagonal first pixel unit.

[0043] Therefore, in the embodiments of the present application, since the pixel array in the image sensor comprises at least two first pixel units, each of which is hexagonal and comprises at least four pentagonal sub-pixels, a plurality of sub-pixels in the pixel unit can output a plurality of light sensing values in a single exposure process, thereby obtaining a plurality of images with different or same exposure values, and then completing HDR synthesis and multi-frame noise reduction function, so as to effectively avoid the occurrence of image misregistration, trailing and other phenomena, and at the same time, the resolution and light sensing capability of the image sensor can be improved, the dynamic range is expanded, and the imaging quality is improved.

[0044] In some embodiments of the present application, the first pixel unit includes four pentagonal sub-pixels, and the four pentagonal sub-pixels include three types of sub-pixels: red sub-pixels, green sub-pixels and blue sub-pixels. That is, the sub-pixels in the first sub-pixel are pentagonal, which can be regular pentagons or irregular pentagons, and the number of sub-pixels is four, and the first pixel unit includes three types of sub-pixels: red sub-pixels, green sub-pixels and blue sub-pixels. In this way, the first pixel unit can realize the photosensitive effect of multiple visible light bands through multiple different types of sub-pixels, and the sub-pixel arrangement structure is compact and reasonable, which can improve the pixel density and then improve the photosensitivity.

[0045] In some embodiments of the present application, the first pixel unit includes one red sub-pixel, two green sub-pixels and one blue sub-pixel, i.e., a total of four sub-pixels. Alternatively, the two green sub-pixels are adjacent and the red sub-pixel and the blue sub-pixel are not adjacent, or the two green sub-pixels are not adjacent and the red sub-pixel and the blue sub-pixel are adjacent. In this way, the R / G / B in the embodiments of the present application can realize the adding processing, and the adding processing can further improve the photosensitive ability of the image sensor when shooting in a darker shooting environment, thereby improving the night shooting effect.

[0046] In some embodiments of the present application, the areas of the four sub-pixels in the first pixel unit can be designed according to actual needs. Alternatively, the area ratio of the two green sub-pixels can be designed as 1:2, so that the photosensitive values of the two green sub-pixels with a ratio of 1:2 can be obtained through one exposure. On this basis, if the capacitance ratio of the two capacitors for reading the photodiode corresponding to the sub-pixel in the pixel circuit is set to 1:4, then the photosensitive values of the two green sub-pixels with a ratio of 1:8 can be finally obtained, thereby further expanding the dynamic range of the image.

[0047] In some embodiments of the present application, the areas of the four sub-pixels in the first pixel unit can be designed according to actual needs. Alternatively, the area ratio of the two green sub-pixels can be designed as 1:2, so that the photosensitive values of the two green sub-pixels with a ratio of 1:2 can be obtained through one exposure. On this basis, if the capacitance ratio of the two capacitors for reading the photodiode corresponding to the sub-pixel in the pixel circuit is set to 1:4, then the photosensitive values of the two green sub-pixels with a ratio of 1:8 can be finally obtained, thereby further expanding the dynamic range of the image.

[0048] Please refer to Figure 1 and Figure 2 , Figure 1 a schematic diagram of the first pixel unit provided by the embodiments of the present application, Figure 2This is one of the schematic diagrams of a pixel array provided in an embodiment of this application. For example... Figure 1 As shown, the first pixel unit 10 includes a red sub-pixel R, two green sub-pixels G, and a blue sub-pixel B. Each sub-pixel is pentagonal, and the two green sub-pixels G are not adjacent, while the red sub-pixel R and the blue sub-pixel B are adjacent. Figure 2 As shown, multiple first pixel units 10 are arranged in an array, and the first pixel units 10 are closely attached to each other to form a pixel array 1.

[0049] like Figure 2 As shown, in some embodiments, the pixel array 1 further includes a second pixel unit 20, which includes at least a pair of PD pixels. PD stands for phase detection, and PD focusing is achieved through phase detection. PD pixels may include a left (L) pixel and a right (R) pixel. The phase difference of the focusing area can be calculated using the pixel values ​​of the L and R pixels in the PD pixels, thereby achieving phase focusing. Optionally, the second pixel unit 20 may have the same shape as the first pixel unit 10, i.e., both being hexagonal, to facilitate the arrangement of the first pixel unit 10 and the second pixel unit 20.

[0050] Please refer to Figure 3 and Figure 4 , Figure 3 The second schematic diagram of the first pixel unit provided in the embodiments of this application. Figure 4 This is a second schematic diagram of a pixel array provided in an embodiment of this application. Figure 3 As shown, the first pixel unit 10 includes a red sub-pixel R, two green sub-pixels G, and a blue sub-pixel B. Each sub-pixel is pentagonal, and the two green sub-pixels G are adjacent, while the red sub-pixel R and the blue sub-pixel B are not adjacent. Figure 4 As shown, multiple first pixel units 10 are arranged in an array, and the first pixel units 10 are closely attached to each other to form a pixel array 1.

[0051] like Figure 4 As shown, in some embodiments, the pixel array 1 further includes a second pixel unit 20, which includes at least one pair of PD pixels to enable focusing of the image sensor. The specific principle of the PD pixel is described in the above embodiments and will not be repeated here. Optionally, the second pixel unit 20 may have the same shape as the first pixel unit 10, i.e., both being hexagonal, to facilitate the arrangement of the first pixel unit 10 and the second pixel unit 20.

[0052] In some embodiments of the present application, the first pixel unit comprises one red sub-pixel, one green sub-pixel, one blue sub-pixel and one first sub-pixel, wherein the first sub-pixel is a white sub-pixel or an infrared sub-pixel. That is, in one scheme, the first pixel unit comprises one red sub-pixel, one green sub-pixel, one blue sub-pixel and one white sub-pixel; and in another scheme, the first pixel unit comprises one red sub-pixel, one green sub-pixel, one blue sub-pixel and one infrared sub-pixel. In this way, by adding a white sub-pixel or an infrared sub-pixel in the first pixel unit, the light sensing capability of the image sensor in a dark environment can be improved, and both the W / IR and G channels can be added, which can further improve the light sensing capability.

[0053] Please refer to Figure 5 and Figure 6 , Figure 5 Figure 3 is a schematic view of a first pixel unit according to an embodiment of the present application, Figure 6 Figure 4 is a schematic view of a pixel array according to an embodiment of the present application. As shown in Figure 5 , the first pixel unit 10 comprises one red sub-pixel R, one green sub-pixel G, one blue sub-pixel B and one first sub-pixel 14, and the first sub-pixel 14 can be a white sub-pixel or an infrared sub-pixel. As shown in Figure 6 , a plurality of first pixel units 10 are arranged in an array, and the first pixel units 10 are closely attached to each other to form a pixel array 1.

[0054] As shown in Figure 6 , in some embodiments, the pixel array 1 further comprises a second pixel unit 20, and the second pixel unit 20 comprises at least one pair of PD pixels. The specific principle of the PD pixel is described above and will not be repeated here. Optionally, the second pixel unit 20 can have the same shape as the first pixel unit 10, i.e., both are hexagonal, so as to facilitate the arrangement of the first pixel unit 10 and the second pixel unit 20.

[0055] In another embodiment of the present application, the first pixel unit comprises six pentagonal sub-pixels and one hexagonal sub-pixel, wherein the six edges of the hexagonal sub-pixel are respectively coincident with one edge of the six pentagonal sub-pixels. In this way, by using such an arrangement, the sub-pixels in the first pixel unit can be closely arranged, thereby improving the pixel density and ultimately improving the light sensitivity of the image sensor.

[0056] In some embodiments of the present application, the first pixel unit further comprises six triangular sub-pixels, and the triangular sub-pixels are located between two adjacent pentagonal sub-pixels. That is, two sides of the triangular sub-pixel are coincident with one side of the two adjacent pentagonal sub-pixels, respectively. In this way, the number of sub-pixels accommodated by the first pixel unit can be further increased, the pixel density can be further improved, and the light sensitivity of the image sensor can be further improved.

[0057] In some embodiments, the triangular sub-pixel can be designed as a PD pixel to realize a phase focusing function, thereby improving the focusing capability of the image sensor. Alternatively, the triangular sub-pixel can be a white sub-pixel.

[0058] In some embodiments of the present application, the hexagonal sub-pixel in the first pixel unit is any one of a white sub-pixel, a green sub-pixel, and an infrared sub-pixel, and the six pentagonal sub-pixels in the first pixel unit comprise at least two pixel types of a red sub-pixel, a green sub-pixel, a blue sub-pixel, a cyan sub-pixel, a magenta sub-pixel, and a yellow sub-pixel. In this way, the color restoration degree and the light sensitivity of the image sensor can be improved.

[0059] In some embodiments of the present application, when the hexagonal sub-pixel is a green sub-pixel, the six pentagonal sub-pixels in the first pixel unit are three red sub-pixels and three blue sub-pixels, respectively. Through such a pixel arrangement, a horizontal addition processing can be realized to improve the image light sensitivity in a dark environment. In this pixel arrangement, 3 sub-pixels of the same color (i.e., red or blue) can be read during one exposure process. Since the areas of the three sub-pixels of the same color are the same, the photoelectric diodes corresponding to the three sub-pixels of the same color are sequentially connected to a capacitor in the pixel circuit for reading the light sensing data, so that the electrons of the photoelectric diodes corresponding to the three sub-pixels of the same color are sequentially entered into the capacitor for reading the light sensing data. Then, the light sensing values of 1:2:3 can be obtained, i.e., the original image data of 1:2:3 can be obtained. In this way, the dynamic range of the image can be expanded, and the light sensing data of the three sub-pixels of the same color can be read through one capacitor, so that the design of the pixel circuit can be facilitated.

[0060] Please refer to Figure 7 and Figure 8 , Figure 7 a fourth schematic view of the first pixel unit provided by an embodiment of the present application, Figure 8 a fourth schematic view of a pixel array provided by an embodiment of the present application. As Figure 7As shown, the first pixel unit 10 includes a hexagonal green sub-pixel G, three pentagonal red sub-pixels R, and three pentagonal blue sub-pixels B, and the six sides of the green sub-pixel G coincide with one side of each of the six pentagonal sub-pixels. Optionally, three sub-pixels of the same color can be arranged adjacent to each other. Figure 8 As shown, multiple first pixel units 10 are arranged in an array, and the first pixel units 10 are closely attached to each other to form a pixel array 1.

[0061] like Figure 8 As shown, in some embodiments, the first pixel unit 10 further includes six triangular PD pixels 16 for phase detection autofocus. The specific principle of the PD pixels 16 is described in the above embodiments and will not be repeated here. Therefore, the solution of this embodiment can improve the focusing capability of the image sensor.

[0062] In some embodiments of this application, when the hexagonal sub-pixels are white sub-pixels or infrared sub-pixels, the six pentagonal sub-pixels in the first pixel unit include two green sub-pixels, two red sub-pixels, and two blue sub-pixels; or, the six pentagonal sub-pixels in the first pixel unit include one red sub-pixel, one green sub-pixel, one blue sub-pixel, one cyan sub-pixel, one magenta sub-pixel, and one yellow sub-pixel.

[0063] The above scenarios will be described in detail below.

[0064] In some embodiments, when the hexagonal sub-pixels in the first pixel unit are white sub-pixels, the six pentagonal sub-pixels in the first pixel unit can specifically be two green sub-pixels, two red sub-pixels, and two blue sub-pixels. With this pixel arrangement, the first pixel unit has white sub-pixels and the largest area, which can significantly improve the light sensitivity, color capture capability, and dynamic range of the pixel sensor.

[0065] Please refer to Figure 9 and Figure 10 , Figure 9 This is the fifth schematic diagram of the first pixel unit provided in the embodiments of this application. Figure 10 This is the fifth schematic diagram of a pixel array provided in an embodiment of this application. Figure 9 As shown, the first pixel unit 10 includes a hexagonal white sub-pixel W, two pentagonal red sub-pixels R, two pentagonal green sub-pixels G, and two pentagonal blue sub-pixels B. The six sides of the white sub-pixel W coincide with one side of each of the six pentagonal sub-pixels. Optionally, two sub-pixels of the same color can be symmetrically arranged about the center point of the first pixel unit. For example, the two pentagonal red sub-pixels R are symmetrically arranged about the center point of the first pixel unit.Figure 10 As shown in the figure, a plurality of first pixel units 10 are arranged in an array, and the first pixel units 10 are closely attached to each other to form a pixel array 1.

[0066] As shown in the figure, in some embodiments, the first pixel unit 10 further includes six PD pixels 16 in a triangular shape for phase focusing. The specific principle of the PD pixels 16 is described in the above embodiments, which will not be repeated here. Thus, the scheme of the present embodiment can improve the focusing capability of the image sensor. Figure 10

[0067] In some embodiments, when the sub-pixel in a hexagonal shape in the first pixel unit is a white sub-pixel, the six sub-pixels in a pentagonal shape in the first pixel unit can specifically be one red sub-pixel, one green sub-pixel, one blue sub-pixel, one cyan sub-pixel, one magenta sub-pixel, and one yellow sub-pixel. Under this pixel arrangement, the first pixel unit has a white sub-pixel with the largest area, which can greatly improve the light sensing capability, color capturing capability, and dynamic range of the pixel sensor; and since CMY (i.e., cyan-magenta-yellow) is the complementary color of RGB (i.e., red-green-blue) and has a higher light sensing sensitivity than RGB, the color information of RGB can be mutually referenced, thereby improving the color restoration accuracy of the image sensor; in addition, if the white sub-pixel in the first pixel unit can be exposed respectively, the dynamic range of the image sensor can be further expanded.

[0068] As shown in the figure, in some embodiments, the first pixel unit 10 further includes six PD pixels 16 in a triangular shape for phase focusing. The specific principle of the PD pixels 16 is described in the above embodiments, which will not be repeated here. Thus, the scheme of the present embodiment can improve the focusing capability of the image sensor. Figure 11 Figure 12 Figure 11 As shown in the figure, in some embodiments, the first pixel unit 10 further includes six PD pixels 16 in a triangular shape for phase focusing. The specific principle of the PD pixels 16 is described in the above embodiments, which will not be repeated here. Thus, the scheme of the present embodiment can improve the focusing capability of the image sensor. Figure 12 As shown in the figure, in some embodiments, the first pixel unit 10 further includes six PD pixels 16 in a triangular shape for phase focusing. The specific principle of the PD pixels 16 is described in the above embodiments, which will not be repeated here. Thus, the scheme of the present embodiment can improve the focusing capability of the image sensor. Figure 11 As shown in the figure, the first pixel unit 10 includes one white sub-pixel W in a hexagonal shape, one red sub-pixel R in a pentagonal shape, one green sub-pixel G in a pentagonal shape, one blue sub-pixel B in a pentagonal shape, one cyan sub-pixel C in a pentagonal shape, one magenta sub-pixel M in a pentagonal shape, and one yellow sub-pixel Y in a pentagonal shape, and the six edges of the white sub-pixel W are respectively coincident with one edge of the six sub-pixels in a pentagonal shape. Figure 12 As shown in the figure, a plurality of first pixel units 10 are arranged in an array, and the first pixel units 10 are closely attached to each other to form a pixel array 1.

[0069] As shown in the figure, in some embodiments, the first pixel unit 10 further includes six PD pixels 16 in a triangular shape for phase focusing. The specific principle of the PD pixels 16 is described in the above embodiments, which will not be repeated here. Thus, the scheme of the present embodiment can improve the focusing capability of the image sensor. Figure 12 As shown in the figure, in some embodiments, the first pixel unit 10 further includes six PD pixels 16 in a triangular shape for phase focusing. The specific principle of the PD pixels 16 is described in the above embodiments, which will not be repeated here. Thus, the scheme of the present embodiment can improve the focusing capability of the image sensor.​​​

[0070] In some embodiments, when the sub-pixel in the hexagonal shape in the first pixel unit is an infrared sub-pixel, the six pentagonal sub-pixels in the first pixel unit can specifically be one red sub-pixel, one green sub-pixel, one blue sub-pixel, one cyan sub-pixel, one magenta sub-pixel, and one yellow sub-pixel. In this pixel arrangement, the first pixel unit has an infrared sub-pixel and has the largest area, which can greatly improve the light sensing capability, color capturing capability, and dynamic range of the pixel sensor. Moreover, since CMY (i.e., cyan-magenta-yellow) is the complementary color of RGB (i.e., red-green-blue) and has a higher light sensing sensitivity than RGB, the color information of RGB and CMY can be mutually referenced, thereby improving the color restoration accuracy of the image sensor. In addition, if the infrared sub-pixel in the first pixel unit can be exposed respectively, the dynamic range of the image sensor can be further expanded.

[0071] Please refer to Figure 13 and Figure 14 , Figure 13 Figure 7 is a schematic view of a first pixel unit provided in an embodiment of the present application, Figure 14 Figure 7 is a schematic view of a pixel array provided in an embodiment of the present application. As shown in Figure 13 , the first pixel unit 10 includes one infrared sub-pixel IR in a hexagonal shape, one red sub-pixel R in a pentagonal shape, one green sub-pixel G in a pentagonal shape, one blue sub-pixel B in a pentagonal shape, one cyan sub-pixel C in a pentagonal shape, one magenta sub-pixel M in a pentagonal shape, and one yellow sub-pixel Y in a pentagonal shape, and the six edges of the infrared sub-pixel IR coincide with one edge of the six pentagonal sub-pixels, respectively. As shown in Figure 14 , a plurality of first pixel units 10 are arrayed and closely attached to each other to form a pixel array 1.

[0072] As shown in Figure 14 , in some embodiments, the first pixel unit 10 further includes six PD pixels 16 in a triangular shape for phase focusing. The specific principle of the PD pixels 16 is described above and will not be repeated here. Thus, the scheme of the present embodiment can improve the focusing capability of the image sensor.

[0073] Please refer to Figure 15 and Figure 16 , Figure 15 Figure 8 is a schematic view of a first pixel unit provided in an embodiment of the present application, Figure 16 Figure 8 is a schematic view of a pixel array provided in an embodiment of the present application. As shown in Figure 15 and Figure 16As shown, in some embodiments of the present application, the first pixel unit 10 includes six pentagonal sub-pixels, one hexagonal sub-pixel, and six triangular sub-pixels, i.e., a total of 13 sub-pixels. Specifically, the six edges of the hexagonal sub-pixel coincide with one edge of the six pentagonal sub-pixels respectively, and the triangular sub-pixel is located between two adjacent pentagonal sub-pixels, i.e., two edges of the triangular sub-pixel coincide with one edge of the two adjacent pentagonal sub-pixels respectively. Among them, the visible light band is divided into 13 sub-bands, and each sub-pixel in the first pixel unit is used to correspond to the light of one sub-band. Exemplarily, the sub-pixel with a larger area can be used to correspond to the light of a sub-band with weaker energy, and the sub-pixel with a smaller area can be used to correspond to the light of a sub-band with stronger energy. In this embodiment, by using the above pixel arrangement manner, the multispectral light sensing capability of the image sensor can be effectively enhanced, the color can be better restored, and the accuracy of white balance, automatic exposure and other algorithms can be improved. It can be understood that the number of sub-pixels in the first pixel unit is the same as the number of sub-bands, and the corresponding light sensing sub-bands of each sub-pixel are different. The number of sub-pixels contained in the first pixel unit can be determined according to actual needs.

[0074] Optionally, the visible light band can be specifically 400-780 nm.

[0075] Please refer to Figures 17 to 19 , Figure 17 for one of the wave band diagrams of red, green and blue colors provided by the embodiments of the present application, Figure 18 for a diagram of dividing the red, green and blue colors into six sub-bands provided by the embodiments of the present application, Figure 19 for a diagram of dividing the visible light band into 13 sub-bands provided by the embodiments of the present application. As Figure 17 shown, the image that can be seen by the normal human eye is composed of R, G and B spectral data, and in the visible light band, it includes a red light band, a green light band and a blue light band. Further, the R spectrum can be further divided into 2 or more, and the B spectrum and the G spectrum are the same, as Figure 18 shown, the red light band, the green light band and the blue light band are respectively divided into 2 smaller bands. Further, as Figure 19 shown, the visible light band can be divided into 13 sub-bands, so that each sub-pixel in the first pixel unit corresponds to the light of one sub-band.

[0076] In some embodiments of the present application, the first pixel unit is a regular hexagon, and the first pixel unit includes six regular pentagonal sub-pixels and one regular hexagonal sub-pixel. Thus, the sub-pixels in the first pixel unit are arranged in order, and the pixel array formed by the first pixel unit is also arranged in order, so as to improve the pixel density of the image sensor, and then improve the light sensing capability.

[0077] The pixel circuit structure used to read the data of the photodiode corresponding to the sub-pixel is described below.

[0078] Please refer to Figure 20 , Figure 20 This is one of the schematic diagrams of a pixel circuit structure provided in an embodiment of this application. For example... Figure 20 As shown, this pixel circuit structure is called a PPD (Pinned Photodiode) pixel structure. A PPD pixel includes a photosensitive area (PD1), i.e., a photodiode, and four transistors (a reset transistor RST, a floating switch TX1, a row selector SET, and a signal amplifier SF), hence it is also called a 4T pixel structure. The PPD allows for the introduction of Correlated Double Sample (CDS) circuitry, eliminating kTC noise introduced by the reset, 1 / f noise introduced by the MOSFET, and offset noise. The operation of this pixel circuit structure is as follows:

[0079] 1. Exposure. Reset transistor RST and floating switch TX1 are turned on simultaneously to clear photodiode PD1. Then, they are disconnected to begin exposure. Electron-hole pairs generated by light irradiation will separate due to the presence of the electric field of photodiode PD1, with electrons moving to the n-region and holes moving to the p-region.

[0080] 2. Reset. At the end of the exposure, activate the reset transistor RST to reset capacitor FD1 to a high level.

[0081] 3. Reset Level Readout. After the reset is completed, the reset level of capacitor FD1 is read out, which includes the offset noise of the MOSFET, 1 / f noise, and kTC noise introduced by the reset. The readout signal is stored in the first capacitor.

[0082] 4. Charge Transfer. Activating the floating switch TX1 completely transfers the charge from the photosensitive area to the capacitor FD1 for readout. This mechanism is similar to charge transfer in a CCD.

[0083] 5. Signal Level Readout. Next, the voltage signal of capacitor FD1 is read out to capacitor FD2. This voltage signal includes: the signal generated by photoelectric conversion, the offset generated by the operational amplifier, 1 / f noise, and kTC noise introduced by reset.

[0084] 6. Signal Output. The signals stored in capacitors FD1 and FD2 are subtracted (if CDS is used, the main noise in the pixel can be eliminated), and the resulting signal is amplified by analog and then sampled by ADC to output a digital signal.

[0085] Figure 20 In this circuit, transistor DCG1 acts as a parallel control switch for capacitors FD1 and FD2. Assuming the capacitance ratio of FD1 and FD2 is set to 1:4, when reading data from the photodiodes of the two green sub-pixels, transistor DCG1 can be controlled to read out electrons from the photodiodes at 1 or 4 times the voltage. This allows for the acquisition of two images with a 1:4 exposure ratio in a single exposure, thus expanding the dynamic range. If the area ratio of the two green sub-pixels is designed to be 1:2, then a 1:8 ratio of light sensitivity values ​​for the two green sub-pixels can be obtained, further expanding the dynamic range.

[0086] Please refer to Figure 21 , Figure 21 This is a second schematic diagram of the pixel circuit structure provided in an embodiment of this application. Figure 21 As shown, with Figure 20 The difference lies in the capacitor used for data reading: FD1. The pixel circuit structure includes three photodiodes: PD1, PD2, and PD3. When reading three sub-pixels of the same color and area, the floating switch TX1 is first opened to read data from PD1 via capacitor FD1. Then, floating switches TX2 and TX3 are opened sequentially, allowing electrons from PD2 and PD3 to enter capacitor FD1. Since the three sub-pixels have the same area, three original image data sets in a 1:2:3 ratio can be obtained with a single exposure, thus expanding the dynamic range. Furthermore, this lateral addition layout allows for easy design of the corresponding readout circuit.

[0087] In summary, in the embodiments of this application, the pixel array in the image sensor includes at least two first pixel units, each pixel unit being hexagonal and including at least four pentagonal sub-pixels. Thus, during a single exposure, multiple sub-pixels in the pixel unit can output multiple light-sensitive values, thereby obtaining multiple images with different or the same exposure values. This enables HDR synthesis and multi-frame noise reduction, effectively avoiding image misalignment, ghosting, and other phenomena. At the same time, it can improve the resolution and light-sensitive capability of the image sensor, expand the dynamic range, and improve the imaging quality.

[0088] This application also provides a camera module, which includes the image sensor described in the above embodiments and can achieve the same technical effect. To avoid repetition, the image sensor will not be described again here.

[0089] Please refer to Figure 22 and Figure 23 , Figure 22 This is an exploded view of the camera module provided in the embodiments of this application. Figure 23A structure schematic diagram of a camera module is provided in the embodiments of the present application. As shown in Figure 22 and Figure 23 The camera module 200 in the embodiments of the present application includes a protective film 201, a lens 202, a voice coil motor 203, a fixing frame 204, a filter 205, an image sensor 206, a flexible circuit board 207 and a connector 208, wherein the protective film 201 is used to protect the lens 202 and the like, the lens 202 is used for light condensation and focusing, the lens 202 is fixed by the voice coil motor 203, the upper and lower ends of the voice coil motor 203 are hinged with the elastic sheet, when the lens 202 focuses, the voice coil motor 203 generates electromagnetic force by being electrified, the electromagnetic force keeps balance with the elastic force of the elastic sheet, the position of the voice coil motor 203 can be controlled by the size of the electrified current, thereby moving the voice coil motor 203 and the lens 202 to the appropriate focusing position, and realizing automatic focusing. The fixing frame 204 is used to fix the components such as the voice coil motor 203; the filter 205 is arranged between the lens 202 and the image sensor 206, and is used to filter the light passing through the lens 202, so as to prevent the image sensor from generating pseudo color / wave, so as to improve the effective resolution and color restoration of the image sensor; the image sensor 206 is used for photosensing, and converts the light signal into an electric signal; the image sensor 206 is connected with the flexible circuit board 207, the flexible circuit board 207 is connected with the connector 208, and then further connected with the processor and the like on the mainboard, so as to realize the transmission of photosensing data.

[0090] The working principle of the camera module in the embodiments of the present application is as follows:

[0091] Step 101: moving the lens 202 to the appropriate focusing position by the voice coil motor 203;

[0092] Step 102: photosensing by the image sensor 206, and converting the light signal into an electric signal;

[0093] Step 103: transmitting the electric signal to the processor by the image sensor 206 through the flexible circuit board 207 and the like, generating an image by image signal processing and compression, and then the image can be used for saving or previewing.

[0094] In the embodiments of the present application, the pixel array in the image sensor includes at least two first pixel units, each of which is hexagonal and includes at least four pentagonal sub-pixels, so that a plurality of sub-pixels in the pixel unit can output a plurality of photosensitive values in one exposure process, thereby obtaining a plurality of images with different or same exposure values, and then completing HDR synthesis and multi-frame noise reduction function, so as to effectively avoid the occurrence of image misregistration, trailing and the like, and at the same time, the resolution and photosensitive capacity of the image sensor can be improved, the dynamic range is expanded, and the imaging quality is improved.

[0095] The electronic device provided in the embodiments of the present application can be a terminal or other device than the terminal. For example, the electronic device can be a mobile phone, a tablet computer, a notebook computer, a palm computer, a vehicle-mounted electronic device, a Mobile Internet Device (MID), an augmented reality (AR) / virtual reality (VR) device, a robot, a wearable device, an ultra-mobile personal computer (UMPC), a netbook, or a personal digital assistant (PDA), etc. The electronic device can also be a personal computer (PC), a television (TV), a teller machine, or a self-service machine, etc. The embodiments of the present application are not limited in this regard.

[0096] The electronic device in the embodiments of the present application can be a terminal or other device than the terminal. For example, the electronic device can be a mobile phone, a tablet computer, a notebook computer, a palm computer, a vehicle-mounted electronic device, a Mobile Internet Device (MID), an augmented reality (AR) / virtual reality (VR) device, a robot, a wearable device, an ultra-mobile personal computer (UMPC), a netbook, or a personal digital assistant (PDA), etc. The electronic device can also be a personal computer (PC), a television (TV), a teller machine, or a self-service machine, etc. The embodiments of the present application are not limited in this regard.

[0097] It should be noted that, in this document, the terms "comprise", "comprising", or any other variant thereof are intended to cover a non-exclusive inclusion, such that processes, methods, articles, or apparatuses that comprise a list of elements are not limited to those elements, but can also include other elements not expressly listed or inherent to such processes, methods, articles, or apparatuses. Without further limitation, an element preceded by "comprises a" does not, without more constraints, foreclose the existence of additional identical elements in the process, method, article, or apparatus that includes the element. In addition, it should be noted that the scope of the methods and apparatuses in the embodiments of the present application is not limited to performing functions in the order shown or discussed, but can also include performing functions in a substantially simultaneous manner or in reverse order, for example, the described methods can be performed in an order different from that described, and various steps can be added, omitted, or combined, in addition, features described with reference to certain examples can be combined in other examples.

[0098] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-described specific embodiments, which are merely illustrative rather than limiting, and a person of ordinary skill in the art can make many forms under the inspiration of the present application without departing from the purpose of the present application and the scope protected by the claims.

Claims

1. An image sensor, characterized by, Comprising: a pixel array comprising at least two first pixel units; the first pixel unit is hexagonal, the first pixel unit comprises six pentagonal sub-pixels, one hexagonal sub-pixel and six triangular sub-pixels, six edges of the hexagonal sub-pixel are coincided with one edge of the six pentagonal sub-pixels respectively, the triangular sub-pixels are located between two adjacent pentagonal sub-pixels; the pentagonal sub-pixels and the hexagonal sub-pixel are used for light sensing, and the triangular sub-pixel is a phase detection (PD) pixel used for focusing.

2. The image sensor of claim 1, wherein, the hexagonal sub-pixel is any one of a white sub-pixel, a green sub-pixel and an infrared sub-pixel, and the six pentagonal sub-pixels comprise at least two of a red sub-pixel, a green sub-pixel, a blue sub-pixel, a cyan sub-pixel, a magenta sub-pixel and a yellow sub-pixel.

3. The image sensor of claim 2, wherein, when the hexagonal sub-pixel is a green sub-pixel, the six pentagonal sub-pixels comprise three red sub-pixels and three blue sub-pixels.

4. The image sensor of claim 2, wherein, when the hexagonal sub-pixel is a white sub-pixel or an infrared sub-pixel, the six pentagonal sub-pixels comprise two green sub-pixels, two red sub-pixels and two blue sub-pixels, or the six pentagonal sub-pixels comprise one red sub-pixel, one green sub-pixel, one blue sub-pixel, one cyan sub-pixel, one magenta sub-pixel and one yellow sub-pixel.

5. The image sensor of claim 1, wherein, each light sensing sub-pixel corresponds to a different light sensing sub-wave band.

6. The image sensor of claim 2, wherein, the first pixel unit is regular hexagonal, the first pixel unit comprises six regular pentagonal sub-pixels and one regular hexagonal sub-pixel.

7. An image capture module, comprising: An image sensor as claimed in any one of claims 1-6.

8. An electronic device, comprising: A camera module as claimed in claim 7.

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