CN110708453A - Image sensor, camera module, terminal and imaging method - Google Patents

Abstract

The application discloses an image sensor, a camera module, a terminal and an imaging method. The image sensor includes a pixel layer, a polarizing layer, and a microlens layer. The pixel layer includes a plurality of pixel groups, each pixel group including a plurality of pixel units. The polarizing layer includes a plurality of polarizing element groups, each polarizing element group includes a plurality of polarizing elements, angles of polarization axes of the plurality of polarizing elements can be different from each other, the polarizing elements correspond to pixel units one to one, and each pixel unit is configured to receive polarized light passing through the corresponding polarizing element. And the micro lens layer comprises a plurality of micro lenses, the micro lenses are used for converging light to enter the corresponding pixel units, the micro lenses corresponding to the center position of the pixel layer are aligned with the corresponding pixel units, and the micro lenses corresponding to the edge position of the pixel layer and the corresponding pixel units are mutually offset. The image sensor, the camera module, the terminal and the imaging method can generate different polarized images according to polarized light with different polarization angles, and the scene utilization range is wide.

Description

Image sensor, camera module, terminal and imaging method

technical field

The present application relates to the technical field of consumer electronics, and in particular, to an image sensor, a camera module, a terminal and an imaging method.

Background technique

The current image sensor cannot distinguish the polarized light of different polarization angles in the shooting scene, and cannot generate different polarized images according to the polarized light of different polarization angles. The polarized light of the polarization angle generates a polarized image, etc., and the scene utilization range is small.

SUMMARY OF THE INVENTION

Embodiments of the present application provide an image sensor, a camera module, a terminal, and an imaging method.

The image sensor of the embodiment of the present application includes a pixel layer, a polarizing layer, and a microlens layer, the pixel layer includes a plurality of pixel groups, and each of the pixel groups includes a plurality of pixel units. The polarizing layer includes a plurality of polarizing element groups, each of the polarizing element groups includes a plurality of polarizing elements, and the angles of the polarization axes of the plurality of the polarizing elements can be different from each other, and the polarizing element and the pixel unit are one. In one correspondence, each of the pixel units is configured to receive polarized light passing through the corresponding polarizing element. The microlens layer includes a plurality of microlenses, the microlenses are used for condensing light to be incident into the corresponding pixel unit, the microlens corresponding to the center position of the pixel layer and the corresponding pixel unit Alignment, the microlenses corresponding to the edge positions of the pixel layers and the corresponding pixel units are offset from each other.

The camera module of the embodiment of the present application includes an image sensor and a lens module. The image sensor is arranged on the image side of the lens module. The image sensor includes a pixel layer, a polarizing layer and a microlens layer, the pixel layer includes a plurality of pixel groups, and each of the pixel groups includes a plurality of pixel units. The polarizing layer includes a plurality of polarizing element groups, each of the polarizing element groups includes a plurality of polarizing elements, and the angles of the polarization axes of the plurality of the polarizing elements can be different from each other, and the polarizing element and the pixel unit are one. In one correspondence, each of the pixel units is configured to receive polarized light passing through the corresponding polarizing element. The microlens layer includes a plurality of microlenses, the microlenses are used for condensing light to be incident into the corresponding pixel unit, the microlens corresponding to the center position of the pixel layer and the corresponding pixel unit Alignment, the microlenses corresponding to the edge positions of the pixel layers and the corresponding pixel units are offset from each other.

The terminal of the embodiment of the present application includes a casing and a camera module. The camera module is mounted on the casing. The camera module includes an image sensor and a lens module. The image sensor is arranged on the image side of the lens module. The image sensor includes a pixel layer, a polarizing layer and a microlens layer, the pixel layer includes a plurality of pixel groups, and each of the pixel groups includes a plurality of pixel units. The polarizing layer includes a plurality of polarizing element groups, each of the polarizing element groups includes a plurality of polarizing elements, and the angles of the polarization axes of the plurality of the polarizing elements can be different from each other, and the polarizing element and the pixel unit are one. In one correspondence, each of the pixel units is configured to receive polarized light passing through the corresponding polarizing element. The microlens layer includes a plurality of microlenses, the microlenses are used for condensing light to be incident into the corresponding pixel unit, the microlens corresponding to the center position of the pixel layer and the corresponding pixel unit Alignment, the microlenses corresponding to the edge positions of the pixel layers and the corresponding pixel units are offset from each other.

The imaging method of the embodiment of the present application includes acquiring pixel values of a plurality of pixel units in each pixel group of an image sensor, where the pixel units are configured to receive polarized light passing through a corresponding polarizing element, which is different from the pixel values in the pixel group. The angles of the polarization axes of the polarization elements corresponding to the pixel units can be different from each other; and a polarization image is generated according to the pixel value of the pixel unit receiving the polarized light of the target polarization angle.

In the image sensor, camera module, terminal, and imaging method of the embodiments of the present application, the angles of the polarization axes of the plurality of polarization elements corresponding to the plurality of pixel units of the pixel group can be different from each other, and the angles of the polarization axes of the plurality of pixel units of the pixel group can be different from each other. It can separately receive polarized light with different polarization angles, and can obtain multiple polarized lights with different polarization angles in the shooting scene, so as to generate different polarization images according to the polarized light with different polarization angles, and the scene can be used in a wide range.

Additional aspects and advantages of embodiments of the present application will be set forth, in part, in the following description, and in part will be apparent from the following description, or learned by practice of embodiments of the present application.

Description of drawings

The above and/or additional aspects and advantages of embodiments of the present application will become apparent and readily understood from the following description of the embodiments in conjunction with the accompanying drawings, wherein:

FIG. 1 is a schematic plan view of a terminal according to some embodiments of the present application.

FIG. 2 is a schematic plan view of a terminal from another perspective according to some embodiments of the present application.

3 is a schematic cross-sectional view of a camera module according to some embodiments of the present application.

FIG. 4 is an exploded schematic view of an image sensor according to some embodiments of the present application.

5 and 6 are schematic plan views of polarizing element groups according to some embodiments of the present application.

FIG. 7 is an exploded schematic diagram of an image sensor according to some embodiments of the present application.

FIG. 8 is a schematic plan view of a pixel layer according to some embodiments of the present application.

FIG. 9 is a schematic cross-sectional view of an image sensor according to some embodiments of the present application.

FIG. 10 is a schematic diagram of the connection between a pixel reading circuit and a pixel unit according to some embodiments of the present application.

11 to 12 are schematic flowcharts of imaging methods according to some embodiments of the present application.

FIG. 13 is a schematic plan view of the polarizing element group in FIG. 6 in another state.

FIG. 14 is a schematic flowchart of an imaging method according to some embodiments of the present application.

Detailed ways

The embodiments of the present application will be further described below with reference to the accompanying drawings. The same or similar reference numbers refer to the same or similar elements or elements having the same or similar functions throughout the drawings.

In addition, the embodiments of the present application described below in conjunction with the accompanying drawings are exemplary, only used to explain the embodiments of the present application, and should not be construed as limitations on the present application.

In this application, unless otherwise expressly stated and defined, a first feature "on" or "under" a second feature may be in direct contact with the first and second features, or the first and second features indirectly through an intermediary touch. Also, the first feature being "above", "over" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is level higher than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature has a lower level than the second feature.

Please refer to FIG. 1 and FIG. 2 , the terminal 1000 according to the embodiment of the present application includes a casing 200 and a camera module 100 . The camera module 100 is mounted on the casing 200 .

Please refer to FIG. 3 , the camera module 100 includes an image sensor 10 and a lens module 20 . The image sensor 10 is disposed on the image side of the lens module 20 .

Referring to FIGS. 4 and 5 , the image sensor 10 according to the embodiment of the present application includes a pixel layer 11 , a polarizing layer 12 and a microlens layer 13 . The pixel layer 11 includes a plurality of pixel groups 111 , and each pixel group 111 includes a plurality of pixel units 112 . The polarizing layer 12 includes a plurality of polarizing element groups 121, each polarizing element group 121 includes a plurality of polarizing elements 122, the angles of the polarization axes of the plurality of polarizing elements 122 can be different from each other, and the polarizing elements 122 correspond to the pixel units 112 one-to-one. Each pixel unit 112 is configured to receive polarized light passing through the corresponding polarizing element 122 . The microlens layer 13 includes a plurality of microlenses 131. The microlenses 131 are used for condensing light to be incident into the corresponding pixel units 112. The microlenses 131 corresponding to the center position of the pixel layer 11 and the corresponding pixel units 112 are aligned and aligned with the pixel units 112. The microlenses 131 corresponding to the edge positions of the layer 11 and the corresponding pixel units 112 are offset from each other.

In the image sensor 10 of the present application, the angles of the polarization axes of the nine polarizing elements 122 corresponding to the nine pixel units 112 of the pixel group 111 can be different from each other, and the nine pixel units 112 of the pixel group 111 can respectively receive different polarizations The polarized light of different angles can obtain the polarized light of nine different polarization angles in the scene being photographed, so as to generate different polarized images according to the polarized light of different polarization angles, and the scene can be used in a wide range. And the microlenses 131 corresponding to the center position of the pixel layer 11 and the corresponding pixel units 112 are aligned, and the microlenses 131 corresponding to the edge positions of the pixel layer 11 and the corresponding pixel units 112 are offset from each other, and the light rays converged by the microlenses 131 are all It can be received by the corresponding pixel unit 132, and the converging effect of the micro lens 131 is better. In addition, according to the polarization image obtained by the image sensor 10 that can receive polarized light with more polarization angles, the present application can obtain polarization information about the properties of the object itself, which can be used to determine the properties of the object such as the material type, surface shape, etc. identification.

Please refer to FIG. 1 and FIG. 2 again, more specifically, the terminal 1000 may be a mobile phone, a tablet computer, a display, a notebook computer, an ATM, a gate, a smart watch, a head-mounted display device, a game console, and the like. The embodiments of the present application are described by taking the terminal 1000 as a mobile phone as an example, and it can be understood that the specific form of the terminal 1000 is not limited to the mobile phone.

The casing 200 can be used to install the camera module 100 , or in other words, the casing 200 can be used as a mounting carrier for the camera module 100 . The terminal 1000 includes a front side 901 and a back side 902. The camera module 100 can be arranged on the front side 901 as a front camera, and the camera module 100 can also be arranged on the back side 902 as a rear camera. The back 902 serves as the rear camera. The housing 200 can also be used to install functional modules such as the camera module 100 , power supply device, and communication device of the terminal 1000 , so that the housing 200 provides protection against dust, drop, and water for the functional modules.

Referring to FIGS. 4 and 5 , in more detail, the image sensor 10 includes a pixel layer 11 , a polarizing layer 12 and a microlens layer 13 . The polarizing layer 12 is located between the pixel layer 11 and the microlens layer 13 .

The pixel layer 11 includes a plurality of pixel groups 111 , and each pixel group 111 includes a plurality of pixel units 112 , for example, each pixel group 111 includes two pixel units 112 , three pixel units 112 , four pixel units 112 , and the like. Each pixel unit 112 is used for receiving incident light for photoelectric conversion, so as to convert optical signals into electrical signals. The plurality of pixel units 112 can be arranged in a matrix, and the pixel arrangement is more compact, which is convenient to cover the entire pixel layer 11 . For example, each pixel group 111 includes two pixel units 112, and the two pixel units 112 are arranged in a matrix of one row and two columns; for another example, each pixel group 111 includes three pixel units 112, and the three pixel units 112 are arranged in a row of three A matrix arrangement of columns; for another example, each pixel group 111 includes four pixel units 112, and the four pixel units 112 are arranged in a matrix of two rows and two columns; for another example, each pixel group 111 includes nine pixel units 112, nine The pixel units 112 are arranged in a matrix of three rows and three columns. In the embodiment of the present application, each pixel group 111 includes nine pixel units 112, and the nine pixel units 112 are arranged in a matrix of three rows and three columns. Of course, the plurality of pixel units 112 may also be arranged in other shapes, such as a trapezoid, and are not limited to the above-mentioned matrix arrangement.

The polarizing layer 12 includes a plurality of polarizing element groups 121 , and each polarizing element group 121 is corresponding to one pixel group 111 . Each polarizing element group 121 includes a plurality of polarizing elements 122, and the angles of the polarizing axes of the plurality of polarizing elements 122 can be different from each other. For example, each polarizing element group 121 includes two polarizing elements 122, three polarizing elements 122, four polarizing elements 122, nine polarizing elements 122, and the like. Corresponding to the pixel group 111 including nine pixel units 112 , in the embodiment of the present application, each polarization element group 121 includes nine polarization elements 122 , and angles of polarization axes of the nine polarization elements 122 can be different from each other. For example, the angles of the polarization axes of the nine polarizing elements 122 are 0°, 20°, 40°, 60°, 80°, 100°, 120°, 140° and 160°, respectively, or the polarizations of the nine polarizing elements 122 The angles of the axes are 5°, 25°, 45°, 65°, 85°, 105°, 125°, 145°, 165°, and so on. The polarizing elements 122 are in one-to-one correspondence with the pixel units 112 , and each pixel unit 112 is configured to receive polarized light passing through the corresponding polarizing element 122 . The nine polarizing elements 122 are also arranged in a matrix of three rows and three columns, which is convenient to cover the entire polarizing layer 12 , and at the same time, makes the nine pixel units 112 more relevant for receiving polarized light passing through the corresponding polarizing elements 122 . Similarly, the nine polarizing elements 122 can also be arranged in other shapes, such as trapezoid, and are not limited to the above-mentioned matrix arrangement of three rows and three columns.

The polarizing element 122 includes a plurality of parallel microstructure units 1221 arranged at intervals, and the microstructure units 1221 are rectangular bodies, such as rectangular parallelepipeds. By setting the angle of the arrangement of the microstructure units 1221, the angle of the polarization axis of the corresponding polarizing element 122 can be determined, and the light rays parallel to the angle of the arrangement of the microstructure units 1221 can pass through the microstructure units 1221, while the non-parallel light rays are passed through the microstructure units 1221. reflection, thereby realizing the polarization of light. In the example shown in FIG. 5 , the angles at which the microstructure units 1221 of the nine polarizing elements 122 are arranged are respectively 0°, 20°, 40°, 60°, 80°, 100°, 120°, 140° and 160° . It can be determined that the angles of the polarization axes of the nine polarizing elements 122 are 0°, 20°, 40°, 60°, 80°, 100°, 120°, 140° and 160°, respectively. The spacing of the microstructure units 1221 can be determined according to the wavelength of the light to be received, and it is only necessary to ensure that the spacing of the adjacent microstructure units 1221 is smaller than the wavelength of the light to be received. For example, during visible light imaging, the adjacent microstructure units 1221 The spacing needs to be smaller than the minimum wavelength of visible light (eg, 380 nanometers) to ensure that the polarizing element 122 can effectively polarize the received light. The material of the microstructure unit 1221 can be metal, and the material of the microstructure unit 1221 is at least one of gold, silver, copper, and aluminum, for example, the material of the microstructure unit 1221 is gold, or the material of the microstructure unit 1221 is silver, Or the material of the microstructure unit 1221 is copper, or the material of the microstructure unit 1221 is iron, or the material of the microstructure unit 1221 is an alloy of gold and silver, the material of the microstructure unit 1221 is an alloy of gold and copper, and the material of the microstructure unit 1221 is an alloy of gold and copper. The material of 1221 is an alloy of gold and iron, etc., which will not be listed here.

6, at least one polarizing element 122 includes a liquid crystal cell 1222, for example, one polarizing element 122 includes a liquid crystal cell 1222, two polarizing elements 122 include a liquid crystal cell 1222, three polarizing elements 122 include a liquid crystal cell 1222, ..., N The polarizing element 122 includes a liquid crystal cell 1222 and the like, and N is a positive integer. The present application takes that all the polarizing elements 122 of the polarizing layer 12 include a liquid crystal cell 1222 as an example for description. The number of the liquid crystal cells 122 in each polarizing element 122 is one or more, which can be set according to the size of the polarizing element 122 and the size of the liquid crystal cell. For example, the number of the liquid crystal cells 122 in each polarizing element 122 is one or two. , three, etc.

The liquid crystal cell 1222 can be deflected under the action of the electric field, thereby changing the angle of the polarization axis of the polarizing element 122, so that the angle of the polarization axis of the polarizing element 122 can be changed within a predetermined angle range, for example, the predetermined angle range can be [0°. , 180°]. In the initial state, the angles of the polarization axes of the nine polarization elements 122 of each polarization element group 121 are 0°, 20°, 40°, 60°, 80°, 100°, 120°, 140° and 160°, respectively , if you want to obtain polarized light with more polarization angles, you can continuously perform multiple exposures (such as two, three, etc.) exposures. After exposure at the angles of the polarization axes of the nine polarizing elements 122 in the initial state, nine The polarized light with a polarization angle is then changed by the liquid crystal unit 1222 to change the angles of the polarization axes of the nine polarizing elements 122 of each polarizing element group 121 (eg, 5°, 25°, 45°, 65°, 85°, respectively). , 105°, 125°, 145°, and 165°) and one more exposure to obtain polarized light at 5°, 25°, 45°, 65°, 85°, 105°, 125°, 145°, and 165° , if you want to obtain polarized light with more polarization angles, you can change the angles of the polarization axes of the nine polarizing elements 122 of each polarizing element group 121 again and perform exposure. In this way, the image sensor 10 can acquire polarized light of any polarization angle within a predetermined angle range according to requirements.

Please refer to FIG. 4 and FIG. 7 , the microlens layer 13 is located on the opposite side of the polarizing layer 12 and the pixel layer 11 . The microlens layer 13 includes a plurality of microlenses 131 . The microlens 131 may be a convex lens, and is used for condensing the light emitted from the lens module 20 to the microlens 131 , so that more light is irradiated on the polarizing layer 12 . Each microlens 131 corresponds to one pixel unit 112, and the pixel unit 112 and the polarizing element 122 are in one-to-one correspondence, that is to say, the microlens 131, the polarizing element 122 and the pixel unit 112 are in one-to-one correspondence; The lens 131 corresponds to a plurality of pixel units 112 in one pixel group 111, and the pixel group 111 corresponds to the polarizing element group 121 one-to-one, that is to say, the microlens 131, the polarizing element group 121 and the pixel group 111 correspond one-to-one .

(即，覆盖像素层11中心位置的两个像素单元112的最小的圆的半径)且小于半径R2(即，像素层11的对角线长度的一半)的多个圆均位于非中心位置，同一个圆上分布的像素单元112和对应的微透镜131的偏移量相同，像素单元112和对应的微透镜131的偏移量与半径的大小呈正相关。其中，偏移量指的是微透镜131在像素层11上的正投影的中心和对应的像素单元112的中心的距离。4 and 8, when each microlens 131 corresponds to one pixel unit 112, the pixel units 112 at the center of the pixel layer 11 (for example, two pixel units 112 near the center of the pixel layer 11) correspond to The microlenses 131 are aligned with the corresponding pixel units 112, and the microlenses corresponding to the pixel units 112 at the edge of the pixel layer 11 (for example, the pixel units 112 except for the two pixel units 112 near the center of the pixel layer 11) 131 and the corresponding pixel unit 112 are offset from each other. Specifically, taking each pixel unit 112 as a square with a side length of L as an example, the center of the pixel layer 11 is the intersection of the diagonal lines of the rectangular pixel layer 11, the center of the pixel layer 11 is the center of the circle, and the center of the pixel layer 11 is greater than the radius

(that is, the radius of the smallest circle covering the two pixel units 112 at the center of the pixel layer 11 ) and the circles smaller than the radius R2 (that is, half of the diagonal length of the pixel layer 11 ) are located at the non-center positions, The offsets of the pixel units 112 and the corresponding microlenses 131 distributed on the same circle are the same, and the offsets of the pixel units 112 and the corresponding microlenses 131 are positively related to the size of the radius. The offset refers to the distance between the center of the orthographic projection of the microlens 131 on the pixel layer 11 and the center of the corresponding pixel unit 112 .

(即，覆盖像素层11中心位置的两个像素组111的最小的圆的半径)且小于半径R2(即，像素层11的对角线长度的一半)的多个圆均位于非中心位置，同一个圆上分布的像素组111和对应的微透镜131的偏移量相同，像素组111和对应的微透镜131的偏移量与半径的大小呈正相关。其中，偏移量指的是微透镜131在像素层11上的正投影的中心和对应的像素组111的中心的距离。具体地，微透镜131和对应的像素单元112(或像素组111)的偏移量与所处圆的半径的大小呈正相关指的是，随着微透镜131所处圆的半径的逐渐增大，微透镜131和对应的像素单元112(或像素组111)的偏移量也逐渐增大。Referring to FIGS. 7 and 8 , when each microlens 131 corresponds to a plurality of pixel units 112 in one pixel group 111 , the pixel group 111 at the center of the pixel layer 11 (for example, 2 pixels near the center of the pixel layer 11 ) The microlenses 131 corresponding to the pixel groups 111) are aligned with the corresponding pixel groups 111, while the microlenses 131 corresponding to the pixel groups 111 at the edge of the pixel layer 11 and the corresponding pixel units 112 are offset from each other. At this time, the microlenses The size of 131 can be set larger, so as to be able to condense all the light rays directed to the pixel group 111 . Specifically, taking each pixel group 111 as a square with a side length of M as an example, the center of the pixel layer 11 is the intersection of the diagonal lines of the rectangular pixel layer 11, the center of the pixel layer 11 is the center of the circle, and the center of the pixel layer 11 is greater than the radius

(that is, the radius of the smallest circle of the two pixel groups 111 covering the central position of the pixel layer 11) and the circles smaller than the radius R2 (that is, half of the diagonal length of the pixel layer 11) are all located at the non-central position, The offsets of the pixel groups 111 and the corresponding microlenses 131 distributed on the same circle are the same, and the offsets of the pixel groups 111 and the corresponding microlenses 131 are positively related to the size of the radius. The offset refers to the distance between the center of the orthographic projection of the microlens 131 on the pixel layer 11 and the center of the corresponding pixel group 111 . Specifically, the positive correlation between the offset of the microlens 131 and the corresponding pixel unit 112 (or pixel group 111 ) and the radius of the circle where the microlens 131 is located means that as the radius of the circle where the microlens 131 is located gradually increases , the offset between the microlens 131 and the corresponding pixel unit 112 (or the pixel group 111 ) also increases gradually.

In this way, when the microlens 131 and the pixel unit 112 (or the pixel group 111 ) are completely aligned without offset, for the pixel layer 11 , some of the light rays converged by the microlens 131 at the edge position cannot be absorbed by the corresponding pixel unit. 112 (or pixel group 111 ) receives it, causing waste of light. In the image sensor 10 of the embodiment of the present application, a reasonable offset is set for the microlens 131 corresponding to the non-center position and the corresponding pixel unit 112 (or pixel group 111 ), which can improve the convergence effect of the microlens 131 , so that the microlens 131 The received light can be received by the corresponding pixel unit 112 (or pixel group 111 ) after being converged.

Referring to FIGS. 4 and 9 , the image sensor 10 further includes a metal wiring layer 14 , which is connected to the pixel layer 11 and is located on the side of the pixel layer 11 opposite to the polarizing layer 12 . The metal wiring layer 14 is used to read the pixel value generated when each pixel unit 112 is exposed.

The metal wiring layer 14 includes a plurality of pixel reading circuits 141 , each of which is connected to a pixel unit 112 for reading the pixel value of the pixel unit 112 .

Referring to FIG. 10 , the pixel reading circuit 141 includes a floating diffusion region 1411 and a transfer transistor 1412 , the floating diffusion region 1411 is used to store charges, and the transfer transistor 1412 is used to connect the photodiode of the pixel unit 112 and the floating diffusion region 1411 to connect the photoelectric The charge generated by the diode is transferred to the floating diffusion region 1411 . The pixel reading circuit 141 is used to determine the pixel value of the corresponding pixel unit 112 according to the charge of the floating diffusion region 1411 .

Specifically, after the pixel unit 112 receives the light passing through the corresponding polarizing element 122, the photodiode produces a photoelectric effect, and the electron-hole pairs generated by the light irradiation will be separated due to the existence of the electric field of the light diode, and the electrons move to the n region , the holes move to the p region, at the end of exposure, the RST is activated, and then the pixel readout circuit 141 resets to make the readout region reset to a high level, after the reset is completed, the reset level is read, and then the transfer transistor 1412 will The charge in the n area is transferred to the floating diffusion area 1411, and then the level of the floating diffusion area 1411 is read out as the signal level, and finally the pixel value of the pixel unit 112 is calculated according to the signal level and the reset level (for example, the signal level and The difference between the reset levels is used as the level corresponding to the pixel value of the pixel unit 112, and then the pixel value of the pixel unit 112 can be calculated according to the level).

Please refer to FIG. 3 again, the lens module 20 includes a substrate 21 , a lens barrel 22 and a lens group 23 . The lens barrel 22 is provided on the substrate 21 .

The substrate 21 may be a flexible circuit board, a rigid circuit board or a flex-rigid circuit board. In the embodiment of the present application, the substrate 21 is a flexible circuit board, which is convenient for installation. The substrate 21 includes a bearing surface 211 .

The lens barrel 22 can be mounted on the bearing surface 211 by screwing, snapping, gluing, or the like. The image sensor 10 is disposed on the bearing surface 211 and located in the lens barrel 22 to correspond to the lens group 23 .

The lens group 23 can be arranged in the lens barrel 22 by means of clamping, gluing, or the like. The lens group 23 may include one or more lenses 231 . For example, the lens group 23 may include one lens 231, which may be a convex lens or a concave lens; for another example, the lens group 23 may include a plurality of lenses 231 (more than or equal to two), and the plurality of lenses 231 may all be convex or concave lenses , or partly convex and partly concave.

In other embodiments, at least one surface of at least one lens 231 in the lens group 23 is a free-form surface. It can be understood that the aspheric lens has only one axis of symmetry due to its rotational symmetry design, so its corresponding imaging area is generally circular. The lens group 23 including the free-form surface is a non-rotationally symmetrical design, including multiple symmetry axes, and the design of the imaging area is not limited by a circle, and can be designed into a rectangle, a rhombus, or even an irregular shape (such as a "D" shape). )Wait. In this embodiment, the imaging area corresponding to the lens group 23 may be rectangular, and the imaging area may just cover the entire pixel layer 11 .

4 and 11, the imaging method of the embodiment of the present application includes:

011: Acquire the pixel values of the plurality of pixel units 112 in each pixel group 111 of the image sensor 10, the pixel units 112 are used to receive polarized light passing through the corresponding polarizing element 122, and the plurality of pixel units in the pixel group 111 The angles of the polarization axes of the plurality of polarization elements 122 corresponding to 112 can be different from each other; and

012: Generate a polarization image according to the pixel value of the pixel unit 112 that receives the polarized light of the target polarization angle.

Specifically, after exposure is completed, the pixel reading circuit 141 can acquire the pixel values of the plurality of pixel units 112 in each pixel group 111 of the image sensor 10, and the plurality of pixel units 112 in each pixel group 111 correspond to The angles of the polarization axes of the plurality of polarizing elements 122 can be different from each other, that is, the plurality of pixel units 112 in each pixel group 111 respectively receive polarized light with different polarization angles, and the plurality of pixel units 112 in each pixel group 111 The pixel values have mutually different polarization information.

Referring to FIG. 1 , the following description will be given by taking each pixel group 111 including nine pixel units 112, each polarizing element group 121 including nine polarizing elements 122 as an example, and each pixel group 111 including other numbers (more than two) of pixels. The unit 112 and each polarizing element group 121 including other numbers (more than two) of polarizing elements 122 are basically similar in principle, and are not repeated here. The terminal 1000 further includes a processor 300, and the processor 300 can generate a polarization image according to the pixel value of the pixel unit 112 receiving the polarized light of the target polarization angle. For example, the angles of the polarization axes of the nine polarization elements 122 are 0°, 20°, 40°, 60°, 80°, 100°, 120°, 140° and 160°, and the target polarization angle is 0°, the processor 300 obtains the pixels in each pixel group 111 that receive polarized light with a polarization angle of 0° For the pixel value of the unit 112, half of the light will be lost after the light passes through the polarization axis, so the received light amount is half of the actual light amount. Therefore, when obtaining the pixel value of the pixel unit 112, it can be calculated according to twice the obtained light amount. Determine the pixel value so that the acquisition of the pixel value is more accurate. The processor 300 then generates a polarization image including polarized light with a polarization angle of 0° according to the acquired pixel values. The target polarization angle can be manually set according to user preferences. For example, in the current scene, an exposure can be performed in advance, and the processor 300 can generate polarization images for each polarization angle (a total of 9 polarization images with different polarization angles are generated), It is presented to the user on the display screen of the terminal 1000, and the user selects a polarization image that he likes the most, and then uses the polarization angle corresponding to the polarization image as the target polarization angle; or, the target user selects the least favorite polarization image, such as When photographing the lake surface, the user does not want to see images such as the reflection of the sky reflected by the lake surface, and can select the polarized image containing the reflection, and the processor 300 uses the polarization angle corresponding to the polarized image not containing the reflection as the target polarization according to the user's selection. At this time, there may be only one polarization image (such as the polarization image corresponding to 100 degrees) containing the reflection image, then the target polarization angles are 0°, 20°, 40°, 60°, 80°, 120°, 140° and 160° °. Then the processor 300 can re-determine the pixel value of the pixel unit 112 according to the pixel value of the pixel unit 112 adjacent to the pixel unit 112 receiving the polarized light of 100°, for example, take the pixel value of the pixel unit 112 adjacent to the pixel unit 112 The average value of the sum of the values is taken as the pixel value of the pixel unit 112 .

Finally, the processor 300 generates a polarized image according to the pixel value re-determined by the pixel unit 112 receiving the 100° polarized light and the pixel values of all other pixel units 112, and the polarized image not only removes the polarization corresponding to the 100° polarized light information (ie, the reflection image that the user does not want in the above example), and the resolution is the same as that of the entire image sensor 10 .

Referring to FIG. 4, FIG. 6 and FIG. 12, in some embodiments, the imaging method further includes:

013: Generate one or more polarized images according to the pixel values of the pixel units 112 that receive polarized light of the same polarization angle;

014: Obtain a target polarization angle based on the clarity of one or more polarization images; and

015: Control the liquid crystal unit 1222 to change the angle of the polarization axis of the polarization element 122 to be the target polarization angle.

Specifically, the target polarization angle can also be automatically set by the processor 300 (shown in FIG. 1 ) according to the captured polarization image. For example, in the current scene, an exposure can be performed in advance, and the processor 300 can generate polarization images for each polarization angle. (For example, a total of 9 polarization images with different polarization angles are generated), and then the sharpness of the nine polarization images is compared, and the polarization angle corresponding to the polarization image with the highest sharpness can be selected as the target polarization angle.

Then the processor 300 controls the liquid crystal unit 1222 of the polarizing element 122 to change the angle of the polarization axis of the polarizing element 122 to the target polarizing angle, so that the nine pixel units 112 in each pixel group 111 receive light with the target polarizing angle. For example, as shown in FIG. 13 , if the target polarization angle is 0°, the processor 300 controls the liquid crystal cells 1222 of the polarization element 122 to rotate to 0°. Compared with the polarization angles of the nine pixel units 112 in each pixel group 111 are different from each other, a polarization image is generated according to the pixel units 112 whose polarization angle is the target polarization angle in each pixel group 111, and the polarization image resolution is In terms of 1/9 of the resolution of the entire sensor 10 , the resolution is the same as the resolution of the entire image sensor 10 , so that it is possible to acquire a polarization image with polarization information of a target polarization angle and a high resolution.

4 and 14, in some embodiments, the imaging method further includes:

016: determine that the pixel unit 112 whose pixel value reaches the predetermined pixel value is the overexposed pixel unit 112; and

017: Determine the pixel value of the overexposed pixel unit 112 according to the pixel value of the pixel unit 112 adjacent to the overexposed pixel unit 112.

Specifically, when the pixel value of a certain pixel unit 112 is overexposed, it indicates that the information of the pixel unit 112 is no longer accurate, the pixel is defined as the overexposed pixel unit 112, and the overexposed pixel unit 112 has a pixel value greater than a predetermined pixel value. The predetermined pixel value can be set as required, such as 180, or a larger value such as 255. For example, a pixel unit 112 with a pixel value greater than 255 is an overexposed pixel unit 112.

The processor 300 (shown in FIG. 1 ) may determine the pixel value of the overexposed pixel unit 112 according to the pixel value of the pixel unit 112 adjacent to the overexposed pixel unit 112 . Since the polarization angles of the polarizing elements 122 corresponding to the adjacent pixel units 112 in the present application can be different from each other, when the polarized light of one polarization angle in the environment is too much, the pixel unit 112 receiving the polarized light of the polarization angle is overexposed, The polarized light of other polarization angles is generally less, that is, the pixel units 112 adjacent to the pixel unit 112 are generally not overexposed. In this case, the pixel unit 112 can be calculated according to the pixel value of the pixel unit 112 adjacent to the pixel unit 112. For example, the average value of the sum of the pixel values of the pixel units 112 adjacent to the pixel unit 112 is taken as the pixel value of the pixel unit 112 . In this way, the processor 300 can recalculate the pixel value of the overexposed pixel unit 112 to prevent the overexposed pixel unit 112 from affecting the image quality.

In the description of this specification, reference is made to the terms "some embodiments," "one embodiment," "some embodiments," "exemplary embodiments," "examples," "specific examples," or "some examples." Described means that a particular feature, structure, material, or characteristic described in connection with an embodiment or example is included in at least one embodiment or example of the present application. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

In addition, the terms "first" and "second" are only used for descriptive purposes, and should not be construed as indicating or implying relative importance or implying the number of indicated technical features. Thus, features delimited with "first", "second" may expressly or implicitly include at least one feature. In the description of the present application, "plurality" means at least two, such as two, three, unless expressly and specifically defined otherwise.

Although the embodiments of the present application have been shown and described above, it should be understood that the above embodiments are exemplary and should not be construed as limitations to the present application. Variations, modifications, substitutions, and alterations are made to the embodiments, and the scope of the present application is defined by the claims and their equivalents.

Claims (10)

1. An image sensor, comprising:

a pixel layer including a plurality of pixel groups, each of the pixel groups including a plurality of pixel units;

the polarizing layer comprises a plurality of polarizing element groups, each polarizing element group comprises a plurality of polarizing elements, the angles of the polarization axes of the plurality of polarizing elements can be different from each other, the polarizing elements and the pixel units are in one-to-one correspondence, and each pixel unit is used for receiving polarized light passing through the corresponding polarizing element

A microlens layer including a plurality of microlenses for converging light to be incident into the corresponding pixel units, the microlenses corresponding to a central position of the pixel layer being aligned with the corresponding pixel units, the microlenses corresponding to edge positions of the pixel layer and the corresponding pixel units being offset from each other.

2. The image sensor of claim 1, wherein the angle of the polarization axis of the polarizing element is variable within a predetermined angular range.

3. The image sensor according to claim 2, wherein the group of polarizing elements includes nine of the polarizing elements whose polarizing axes have angles of 0 degrees, 20 degrees, 40 degrees, 60 degrees, 80 degrees, 100 degrees, 120 degrees, 140 degrees, and 160 degrees, respectively.

4. The image sensor of claim 2, wherein at least one of the polarizing elements comprises a liquid crystal cell for changing an angle of a polarization axis of the polarizing element under an electric field.

5. The image sensor of claim 1, wherein the polarizing layer is located between the microlens layer and the pixel layer;

each microlens corresponds to a plurality of pixel units in one pixel group; or

Each of the microlenses corresponds to one of the pixel cells.

6. A camera module, comprising:

the image sensor of any one of claims 1 to 5; and

the image sensor is arranged on the image side of the lens module.

7. A terminal, comprising:

the camera module of claim 6; and

the camera module is arranged on the shell.

8. An imaging method, characterized in that the imaging method comprises:

acquiring pixel values of a plurality of pixel units in each pixel group of an image sensor, wherein the pixel units are used for receiving polarized light passing through corresponding polarization elements, and angles of polarization axes of the plurality of polarization elements respectively corresponding to the plurality of pixel units in the pixel group can be different from each other; and

generating a polarization image from pixel values of the pixel cells receiving polarized light of a target polarization angle.

9. The imaging method according to claim 8, wherein the polarizing element comprises a liquid crystal cell, the imaging method further comprising:

generating one or more polarized images according to the pixel values of the pixel units receiving the polarized light with the same polarization angle;

obtaining a target polarization angle according to the definition of one or more polarization images; and

and controlling the liquid crystal unit to change the angle of the polarization axis of the polarization element to be the target polarization angle.

10. The imaging method according to claim 8, further comprising:

determining the pixel unit with the pixel value reaching the preset pixel value as an overexposed pixel unit; and

and determining the pixel value of the overexposed pixel unit according to the pixel value of the pixel unit adjacent to the overexposed pixel unit.

Images