Image sensor, three-dimensional imaging device and electronic equipment

Abstract

The utility model provides an image sensor, a three-dimensional imaging device and electronic equipment, and relates to the technical field of biological recognition, the image sensor comprises a pixel array, a receiving side of the pixel array is provided with a polaroid, and the polaroid is provided with a plurality of linear polarization areas; the pixel array comprises a plurality of pixels distributed in an array mode, each pixel is provided with an orthographic projection located on the plane where the polaroid is located, the pixel with the orthographic projection located in the linear polarization area serves as a first pixel, and the pixel with the orthographic projection intersecting with at most parts of any linear polarization area serves as a second pixel; the first pixels and the second pixels are used for receiving light carrying polarization information, and the polarization information corresponds to the contour surface of a target object. Therefore, two-dimensional and three-dimensional imaging of the target object is realized by comprehensively utilizing the first pixels and the second pixels of the pixel array, so that the information of the target object is more comprehensively acquired, and the recognition precision is improved.

Description

Technical Field

[0001] This application relates to the field of biometric technologies, and more particularly, to an image sensor, a three-dimensional imaging device, and an electronic device. Background Art

[0002] With the development of portable terminal devices, the application of biometric technologies has become more and more extensive and in-depth. Taking electronic devices as an example, fingerprint recognition, face recognition, etc. have been increasingly applied in the screen wake-up of devices and the identity authentication steps of various programs, improving the security of the devices and the flexibility of the usage methods.

[0003] Currently, the main solutions for implementing face recognition include binocular vision solutions, time-of-flight solutions, structured light solutions, etc. Among them, in the binocular vision solution, since the reconstruction accuracy is proportional to the camera baseline length, the application range is relatively limited; while the cost of time-of-flight cameras is relatively high, and they are limited by the time resolution, so the accuracy of three-dimensional imaging is not high; although the structured light solution has the advantage of high imaging accuracy, its response speed is slow and the frame rate is low, and as the imaging distance increases, the imaging accuracy decreases. Therefore, another polarization three-dimensional imaging technology that can be used for face recognition has also been gradually developed, but currently, the polarization three-dimensional imaging technology usually has the problem of poor recognition accuracy. Summary of the Utility Model

[0004] The purpose of this application is to provide an image sensor, a three-dimensional imaging device, and an electronic device for the deficiencies in the above-mentioned existing technologies.

[0005] To achieve the above purpose, the technical solutions adopted in the embodiments of this application are as follows:

[0006] On the one hand, an embodiment of this application provides an image sensor, including a pixel array, a polarizer is arranged on the receiving side of the pixel array, and the polarizer has a plurality of linearly polarized regions;

[0007] The pixel array includes a plurality of pixels distributed in an array, each pixel has a positive projection located in the plane of the polarizer, and the pixels whose positive projections are all located within the linearly polarized regions are used as first pixels, and the pixels whose positive projections intersect at most partially with any linearly polarized region are used as second pixels;

[0008] The first pixels and the second pixels are used to receive light carrying polarization information, and the polarization information corresponds to the contour surface of the target object.

[0009] Optionally, the first pixels whose positive projections are all located within the same linearly polarized region form a group of pixel groups, and each pixel group includes at least one first pixel, and the area of the positive projection of the pixel group in the plane of the polarizer is less than or equal to the area of the linearly polarized region.

[0010] Optionally, among the plurality of linear polarization regions, at least some adjacent linear polarization regions are connected to or spaced apart from each other.

[0011] Optionally, two adjacent linear polarization regions have a first center distance in the first direction, two adjacent pixels have a second center distance in the first direction, the first center distance is N times the second center distance, N≥1, the pixel array is distributed in a matrix, and the first direction is the row or column direction of the pixel array.

[0012] Optionally, an area of an orthographic projection of the pixel group is smaller than an area of the linear polarization region, at least some adjacent linear polarization regions are connected to each other, and N>1.

[0013] Optionally, N≥2.

[0014] Optionally, N is an integer greater than 1.

[0015] Optionally, the plurality of pixel groups are distributed along the row direction and the column direction of the pixel array, and a second pixel is provided between two adjacent pixel groups.

[0016] Optionally, among the plurality of linear polarization regions, at least one linear polarization region forms a polarization unit.

[0017] Optionally, when the polarization unit includes at least two linear polarization zones, polarization directions of the at least two linear polarization zones are different.

[0018] Optionally, when the polarization unit includes at least two linear polarization zones, in the same polarization unit, an angle between polarization directions of any two linear polarization zones is greater than 10 degrees.

[0019] Optionally, the polarizer is integrated into the image sensor.

[0020] Optionally, a pixel includes a photosensitive unit and a unit circuit, the photosensitive units of a plurality of pixels are arrayed to form a photosensitive array, and the unit circuits of a plurality of pixels form a pixel circuit:

[0021] The pixel circuit is located between the photosensitive array and the polarizer;

[0022] The pixel circuit is located on the side of the photosensitive array facing away from the polarizer;

[0023] Alternatively, the pixel circuit is located on the side of the polarizer facing away from the photosensitive array.

[0024] Optionally, the polarizing plate is spaced apart from the receiving surface of the image sensor, or the polarizing plate is attached to the receiving surface of the image sensor.

[0025] Optionally, when the polarizer is attached to the receiving surface of the image sensor, the pixel includes a photosensitive unit and a microlens. The photosensitive units of multiple pixels are array - distributed to form a photosensitive array, and the microlenses of multiple pixels are array - distributed to form a microlens array. The microlens array is located between the photosensitive array and the polarizer, and the polarizer is attached to the surface of the microlens array.

[0026] On the other hand, an embodiment of the present application provides a three - dimensional imaging device, including a polarization light source for emitting linearly polarized light and the image sensor of any of the above. The linearly polarized light emitted by the polarization light source forms light carrying polarization information after being reflected by the target object.

[0027] Optionally, the image sensor includes a polarizer having multiple linearly polarized regions, and the polarization direction of the linearly polarized light is the same as the polarization direction of at least one linearly polarized region.

[0028] Optionally, the wavelength band of the linearly polarized light is 850nm ± 10nm or 940nm ± 10nm.

[0029] Optionally, a band - pass filter is provided on the receiving side of the pixel array of the image sensor. The band - pass band of the band - pass filter includes the emission band of the polarization light source, and the half - bandwidth of the band - pass filter is less than 80nm.

[0030] In yet another aspect of the embodiments of the present application, an electronic device is provided, including a device body and the image sensor of any of the above, and the image sensor is located in the device body;

[0031] Or, it includes a device body and the three - dimensional imaging device of any of the above, and the three - dimensional imaging device is located in the device body.

[0032] The beneficial effects of the present application include:

[0033] The present application provides an image sensor, a three - dimensional imaging device, and an electronic device. The image sensor includes a pixel array, and a polarizer is provided on the receiving side of the pixel array. The polarizer has multiple linearly polarized regions; the pixel array includes multiple pixels that are array - distributed. Each pixel has a positive projection on the plane where the polarizer is located. The pixels whose positive projections are all located within the linearly polarized regions are used as the first pixels, and the pixels whose positive projections intersect at most partially with any linearly polarized region are used as the second pixels; the first pixels and the second pixels are used to receive the light carrying polarization information, and the polarization information corresponds to the contour surface of the target object. In this way, by comprehensively using the first pixels and the second pixels of the pixel array, two - dimensional and three - dimensional imaging of the target object is realized, so as to obtain more comprehensive information of the target object, which helps to improve the recognition accuracy. Description of the Drawings

[0034] To more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings required in the embodiments. It should be understood that the following drawings only show some embodiments of the present application and should not be regarded as limiting the scope. For those of ordinary skill in the art, without creative efforts, other related drawings can also be obtained based on these drawings.

[0035] Figure 1 One of the schematic structural diagrams of an image sensor provided by an embodiment of the present application;

[0036] Figure 2 One of the schematic diagrams of the corresponding relationship between a pixel array and a polarizer provided by an embodiment of the present application;

[0037] Figure 3 Two of the schematic diagrams of the corresponding relationship between a pixel array and a polarizer provided by an embodiment of the present application;

[0038] Figure 4 Three of the schematic diagrams of the corresponding relationship between a pixel array and a polarizer provided by an embodiment of the present application;

[0039] Figure 5 The schematic structural diagram of a polarizer provided by an embodiment of the present application;

[0040] Figure 6 The schematic structural diagram of a pixel array provided by an embodiment of the present application;

[0041] Figure 7 Four of the schematic diagrams of the corresponding relationship between a pixel array and a polarizer provided by an embodiment of the present application;

[0042] Figure 8 Five of the schematic diagrams of the corresponding relationship between a pixel array and a polarizer provided by an embodiment of the present application;

[0043] Figure 9 Six of the schematic diagrams of the corresponding relationship between a pixel array and a polarizer provided by an embodiment of the present application;

[0044] Figure 10 Seven of the schematic diagrams of the corresponding relationship between a pixel array and a polarizer provided by an embodiment of the present application;

[0045] Figure 11 Eight of the schematic diagrams of the corresponding relationship between a pixel array and a polarizer provided by an embodiment of the present application;

[0046] Figure 12 Nine of the schematic diagrams of the corresponding relationship between a pixel array and a polarizer provided by an embodiment of the present application;

[0047] Figure 13The second schematic structural diagram of an image sensor provided by an embodiment of the present application;

[0048] Figure 14 The third schematic structural diagram of an image sensor provided by an embodiment of the present application;

[0049] Figure 15 The fourth schematic structural diagram of an image sensor provided by an embodiment of the present application;

[0050] Figure 16 The schematic structural diagram of a three-dimensional imaging device provided by an embodiment of the present application.

[0051] Icons: 100 - human face; 200 - pixel array; 211 - first pixel; 212 - second pixel; 300 - polarizer; 310 - polarization unit; 311 - linearly polarized region; 400 - polarized light source; 410 - linearly polarized light; 600 - pixel circuit; 700 - microlens array; 810 - support frame; 820 - adhesive layer. Detailed implementation manners

[0052] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Apparently, the described embodiments are some, but not all, of the embodiments of the present application. It should be noted that, without conflict, the various features in the embodiments of the present application can be combined with each other, and the combined embodiments are still within the protection scope of the present application.

[0053] In the description of the present application, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of this application is usually placed during use. It is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present application. In addition, the terms "second", "first", "second", etc. are only used for distinguishing descriptions and cannot be understood as indicating or implying relative importance.

[0054] In the description of the present application, it should also be noted that, unless otherwise clearly specified and defined, the terms "arranged", "installed", "connected", and "coupled" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific situations.

[0055] To optimize the imaging effect and improve the recognition accuracy, an image sensor is proposed in an embodiment of the present application, which is capable of receiving the light beam reflected by a target object. During the process of the image sensor receiving the light beam, after partially modulating some regions in the light beam, the light beam forms unmodulated light and multiple polarized lights (if all regions in the light beam are modulated, multiple polarized lights are formed). Subsequently, the unmodulated light (if any) and the multiple polarized lights are received by multiple pixels in the pixel array. In this way, the pixels receiving light of a single polarization state can more accurately reconstruct the contour surface of the target object, and the pixels receiving unmodulated light and / or light of a mixed polarization state participate in two-dimensional imaging of the target object, thereby improving the recognition speed and accuracy. For ease of understanding, the embodiments of the present application will be described below with reference to the accompanying drawings.

[0056] Please refer to Figure 1 , an image sensor is provided, including a pixel array 200, and a polarizer 300 is arranged on the receiving side of the pixel array 200. In this way, when receiving the light reflected by the target object, the polarizer 300 is located in the optical path between the target object and the pixel array 200, so that at least part of the light reflected by the target object can first pass through the polarizer 300 and then be received and imaged by the pixel array 200.

[0057] During the process of light incident on the target object and being reflected by the target object, since the degree of change in the polarization state of light by each point on the contour surface in the target object (the points in the contour surface can be understood as the micro-elements constituting the contour surface) will be different, the light reflected by the target object will carry polarization information corresponding to the contour surface of the target object. Therefore, perceiving and acquiring this polarization information is the key to subsequent reconstruction of the contour surface of the target object.

[0058] To better acquire this polarization information and provide data support for reconstructing the contour surface of the target object, it is necessary for the image sensor to decode the light reflected by the target object, that is, modulate it in regions, so as to comprehensively analyze the modulated light to obtain this polarization information. Specifically, as Figure 2As shown, the polarizer 300 has a plurality of linearly polarized regions 311, so that light can be regionally modulated into a plurality of linearly polarized lights after passing through the plurality of linearly polarized regions 311. Correspondingly, the pixel array 200 includes a plurality of pixels distributed in an array, and each pixel has a front projection located in the plane where the polarizer 300 is located. In order to distinguish the plurality of pixels, the pixels whose front projections are all located within the linearly polarized region 311 can be regarded as the first pixels 211, and the pixels whose front projections intersect at most partially with any one of the linearly polarized regions 311 are regarded as the second pixels 212 (the front projection intersecting at most partially with any one of the linearly polarized regions 311 means that the front projection of the second pixel 212 will not be completely located within any one of the linearly polarized regions 311. For example, the front projection of the second pixel 212 can intersect, be border-connected, or not intersect with any one of the linearly polarized regions 311. Among them, intersection means that the regions of the two partially overlap and do not completely coincide, and non-intersection means that there is no overlapping part between the regions of the two, so as to distinguish the situation where the front projection is located within the linearly polarized region 311). In this way, the corresponding relationship between the first pixels 211 and the linearly polarized regions 311 is established, that is, the first pixel 211 corresponds to the linearly polarized region 311 where its front projection is located.

[0059] Based on the positional relationship between the front projection of the first pixel 211 and the linearly polarized region 311, the linearly polarized light received by the first pixel 211 comes from the linearly polarized region 311 corresponding to it. Therefore, the polarization direction of the linearly polarized light received by the first pixel 211 is consistent with the polarization direction of the linearly polarized region 311 corresponding to it. So the linearly polarized light received by the first pixel 211 has a single polarization state, and the first pixel 211 outputs the corresponding code value. Then, by synthesizing the code values output by each first pixel 211, the polarization information carried by the light reflected by the target object can be obtained, and the degree to which the polarization state of the light is changed by the target object can be obtained using this polarization information. Combining the light corresponding to the microelement in the target object, the normal vector of the microelement can be determined. Based on this, combined with the positions of each first pixel 211, the contour surface of the target object can be reconstructed more accurately, making the reconstructed contour surface closer to the actual contour surface of the target object, so that the first pixel 211 is used to participate in the three-dimensional imaging of the target object.

[0060] Based on the positional relationship between the orthographic projection of the second pixel 212 and the linearly polarized region 311, the light received by the second pixel 212 is relatively complex. For example, there may be the following situations for the light received by the second pixel 212: If the orthographic projection of the second pixel 212 intersects at least one linearly polarized region 311, the light received by the second pixel 212 may be linearly polarized light from the linearly polarized region 311 with which it intersects. Especially when the orthographic projection of the second pixel 212 intersects at least two linearly polarized regions 311, the light received by the second pixel 212 may come from different linearly polarized regions 311. In addition, there may also be unmodulated light. If the orthographic projection of the second pixel 212 is tangent to or does not intersect the boundary of any linearly polarized region 311, the light received by the second pixel 212 is unmodulated light. Therefore, due to the relatively complex and variable situations of the light received by the second pixel 212, there are certain difficulties in reconstructing the contour surface of the target object using the second pixel 212. However, since the light received by the second pixel 212 still comes from the reflected light of the target object, the second pixel 212 can be used to participate in two-dimensional imaging of the target object. In this way, by comprehensively using the first pixel 211 and the second pixel 212 of the pixel array 200, two-dimensional and three-dimensional imaging of the target object can be realized, so as to obtain more comprehensive information of the target object, which helps to improve the recognition accuracy.

[0061] Of course, both the first pixel 211 and the second pixel 212 can participate in two-dimensional imaging of the target object, so as to improve the resolution of the two-dimensional image and thus improve the recognition accuracy.

[0062] It should be understood that the target object in this application can be Figure 1 the human face 100 in, the local parts of the human face 100 (such as cheeks, nose, eyes). Of course, it is not limited to this, and it can also be other objects with three-dimensional dimensions, such as fingers, palms, etc.

[0063] In order to more clearly understand the relationship between the orthographic projections of the first pixel 211 and the second pixel 212 and the linearly polarized region 311, the following will be described by way of example:

[0064] Please refer to Figure 2 , Figure 2Four linear polarization regions C1-C4 of the polarizer 300 are shown, and at the same time, nine pixels A1-A4 and D1-D5 in the pixel array 200 are also shown. Each pixel has a front projection located in the plane where the polarizer 300 is located. Among them, the front projection A1' of pixel A1 is located in the linear polarization region C1. Similarly, the front projection of pixel A2 is located in the linear polarization region C2, the front projection of pixel A3 is located in the linear polarization region C3, and the front projection of pixel A4 is located in the linear polarization region C4. Therefore, pixels A1-A4 are all first pixels 211. The front projection D3' of pixel D3 intersects with the linear polarization regions C1-C4 respectively, and the front projection D5' of pixel D5 intersects with the linear polarization regions C2 and C4 respectively. Similarly, the front projection of pixel D1 intersects with the linear polarization regions C1 and C3 respectively, the front projection of pixel D2 intersects with the linear polarization regions C1 and C2 respectively, and the front projection of pixel D4 intersects with the linear polarization regions C3 and C4 respectively. Therefore, pixels D1-D5 are all second pixels 212.

[0065] Please refer to Figure 3 , the light reflected by the target object is divided into multiple sub-beams according to the different incident linear polarization regions C1-C4. Taking the linear polarization regions C1 and C3 as examples, the sub-beam incident on the linear polarization region C1 is used as the first sub-beam B1, and the sub-beam incident on the linear polarization region C3 is used as the second sub-beam B3. The first sub-beam B1 forms a first modulated sub-beam after being modulated by the linear polarization region C1. The first modulated sub-beam includes a first sub-sub-beam B11 and a second sub-sub-beam B12. The second sub-beam B3 forms a second modulated sub-beam after being modulated by the linear polarization region C3. The second modulated sub-beam includes a third sub-sub-beam B31 and a fourth sub-sub-beam B32. Since pixels A1 and A3 are both first pixels 211, pixel A1 only receives the first sub-sub-beam B11, and pixel A3 only receives the first sub-sub-beam B31. Since pixel D1 is a second pixel 212 and the front projection of pixel D1 intersects with the linear polarization regions C1 and C3 respectively, pixel D1 may receive the second sub-sub-beam B12 and the fourth sub-sub-beam B32. When the polarization directions of the linear polarization regions C1 and C3 are different, the polarization states of the second sub-sub-beam B12 and the fourth sub-sub-beam B32 are different. Pixels A2 and A4 and D2-D5 are the same.

[0066] Please refer to Figure 4 , Figure 4Two linear polarization regions C1 and C2 of the polarizer 300 are shown, and at the same time, nine pixels A1 - A4 and D1 - D5 in the pixel array 200 are also shown. Each pixel has a positive projection on the plane where the polarizer 300 is located. Among them, the positive projection A1' of pixel A1 is located within the linear polarization region C1, and the positive projection A2' of pixel A2 is also located within the linear polarization region C1. Similarly, the positive projections of pixels A3 and A4 are both located within the linear polarization region C2. Therefore, pixels A1 - A4 are all first pixels 211. The positive projection D2' of pixel D2 intersects with the linear polarization regions C1 and C2 partially. Similarly, the positive projection of pixel D1 intersects with the linear polarization regions C1 and C2 partially, the positive projection D4' of pixel D4 intersects with the linear polarization regions C1 and C2 partially, and at the same time, the positive projection D4' of pixel D4 also has a part that does not intersect with the linear polarization regions C1 and C2. Similarly, the positive projection of pixel D3 intersects with the linear polarization region C1 partially, and at the same time, the positive projection of pixel D3 also has a part that does not intersect with the linear polarization region C1. The positive projection of pixel D5 intersects with the linear polarization region C2 partially, and at the same time, the positive projection of pixel D5 also has a part that does not intersect with the linear polarization region C2. Therefore, pixels D1 - D5 are all second pixels 212.

[0067] Of course, in other examples, the positive projections of the first pixels 211 and the second pixels 212 and the linear polarization region 311 may also have a relationship not shown in the figure, as long as the condition that the positive projections of all the first pixels 211 are located entirely within the linear polarization region 311 and the positive projections of the second pixels 212 intersect with any of the said linear polarization regions 311 at most partially is satisfied.

[0068] From the foregoing description, it can be seen that the positive projections of all the first pixels 211 are located entirely within the linear polarization region 311. However, it should be understood that the number of the first pixels 211 whose positive projections are located within the same linear polarization region 311 can be flexible, such as at least one, and can be reasonably set according to requirements. For the convenience of description and understanding, all the first pixels 211 whose positive projections are located within the same linear polarization region 311 are divided into a group of pixel groups, and the area of the positive projection of each group of pixel groups on the polarizer 300 is the sum of the areas of the positive projections of all the first pixels 211 within the group of pixel groups. For example Figure 2 as shown, pixel A1, which is a first pixel 211, forms a group of pixel groups by itself. Therefore Figure 2 four groups of pixel groups are shown, and each group of pixel groups only has one first pixel 211; or for another example Figure 4 as shown, pixel A1 and A2, which are first pixels 211, form a group of pixel groups together, and pixel A3 and A4, which are first pixels 211, form another group of pixel groups together. Therefore Figure 4 two groups of pixel groups are shown, and each group of pixel groups only has two first pixels 211.

[0069] Therefore, the pixel array 200 may include multiple pixel groups, and each pixel group corresponds to the linearly polarized region 311 where its orthographic projection is located, so that multiple pixel groups can correspond to multiple linearly polarized regions 311 one by one. Therefore, the area of the orthographic projection of the pixel group on the polarizer 300 should be less than or equal to the area of the corresponding linearly polarized region 311.

[0070] In some possible embodiments, the multiple linearly polarized regions 311 in the polarizer 300 may be arranged in an array or non-array. Based on the correspondence between the pixel groups and the linearly polarized regions 311, if the pixel groups in the pixel array 200 are arranged in an array, correspondingly, the linearly polarized regions 311 may be arranged in a corresponding array, and vice versa.

[0071] In some possible embodiments, the multiple linearly polarized regions 311 on the polarizer 300 may be adjacent or spaced apart. For example Figures 2 to 5 , Figures 7 to 9 or Figure 11 as shown, the boundaries of adjacent linearly polarized regions 311 may be adjacent; or for another example Figure 10 or Figure 12 as shown, there is a gap between adjacent linearly polarized regions 311, and the gap region is a non-linearly polarized region; of course, it may also be that some of the linearly polarized regions 311 are adjacent and some are spaced apart. It should be understood that in this application, adjacent linearly polarized regions 311 refer to being adjacent along the row and / or column direction of the pixel array 200.

[0072] In some possible embodiments, the polarizer 300 includes a substrate (translucent) and a polarization layer located on the surface of the substrate. The polarization layer includes multiple polarization sub-layers laid flat on the surface of the substrate, and each polarization sub-layer correspondingly forms a linearly polarized region 311 as described above. Among them, the polarization sub-layer may be a metal wire grid, and the polarization direction within the linearly polarized region 311 formed by the polarization sub-layer can be determined by the metal wire grid, because the metal wire grid can transmit linearly polarized light perpendicular to the direction of the metal wire grid. For example Figure 3 in, the metal wire grid forming the linearly polarized region C1 has an angle of 90 degrees with the horizontal direction, and the polarization direction of the linearly polarized region C1 has an angle of 0 degrees with the horizontal direction. Therefore, the linearly polarized region C1 can transmit linearly polarized light with an angle of 0 degrees with the horizontal direction.

[0073] To facilitate understanding of the area relationship between the linearly polarized region 311 and the pixels, the center spacing is introduced. Adjacent two linearly polarized regions 311 have a first center spacing in a first direction, adjacent two pixels have a second center spacing in the first direction, and the pixel array 200 is distributed in a matrix, and the first direction is the row or column direction of the pixel array 200. For example Figure 5 and Figure 6As shown, the pixel array 200 is distributed in a matrix, and multiple polarization regions are also distributed in a corresponding matrix. The adjacent two linear polarization regions 311 have a first center pitch L1 in the row direction of the matrix, and the adjacent two pixels also have a second center pitch L2 in the row direction of the matrix. The same applies to the column direction.

[0074] When the area of the positive projection of the pixel group on the plane where the polarizer 300 is located is less than or equal to the area of the linear polarization region 311, the first center pitch is N times the second center pitch, N≥1, that is, the first center pitch is greater than or equal to the second center pitch. Of course, the value range of N can change according to the area relationship between the pixel group and the linear polarization region 311 and whether the linear polarization regions 311 are adjacent. For the convenience of understanding, some examples will be described below:

[0075] Example 1

[0076] When the area of the positive projection of the pixel group is less than the area of the linear polarization region 311, and at least some adjacent linear polarization regions 311 are adjacent to each other, the two adjacent linear polarization regions 311 have a first center pitch in the first direction, and the adjacent pixels have a second center pitch in the first direction. The first center pitch and the second center pitch satisfy: the first center pitch is N times the second center pitch, and N>1.

[0077] Theoretically, when the polarizer 300 is arranged on the receiving side of the pixel array 200, the center of the positive projection of the pixel group on the plane where the polarizer 300 is located is preferably coincident with the center of the corresponding linear polarization region 311, that is, the center of the pixel group is aligned with the center of the corresponding linear polarization region 311. In this way, the center connection line between the pixel group and the corresponding linear polarization region 311 will be parallel to the perpendicular line of the plane where the polarizer 300 is located. However, in actual settings, due to the alignment accuracy limitation, there may be a certain alignment error. But based on the aforementioned condition of N>1, a certain alignment error between the center of the pixel group and the center of the corresponding linear polarization region 311 can be allowed.

[0078] For example: Please refer to Figure 5 shows a polarizer 300 from a top view. The polarizer 300 includes 16 linear polarization regions 311, and the linear polarization regions 311 in the polarizer 300 are distributed in a matrix, and the adjacent linear polarization regions 311 are adjacent to each other along the row or column direction of the matrix. The first center pitch of the adjacent linear polarization regions 311 in the first direction is L1, and the first direction is the row or column direction of the pixel array 200.

[0079] Please refer to Figure 6Fig. 0 shows a pixel array 200 in a top view. The pixel array 200 includes 49 pixels, and the pixels in the pixel array 200 are distributed in a matrix. The second center pitch of adjacent pixels in the first direction is L2, and the first direction is the row or column direction of the pixel array 200. Among them, the pixel array 200 includes 16 first pixels 211 and 33 second pixels 212, and each first pixel 211 is a group of pixel groups.

[0080] When the polarizer 300 is disposed on the receiving side of the pixel array 200, that is Figure 5 the polarizer 300 in Figure 6 is placed above the pixel array 200 in

[0081] Please refer to Figure 7 , the polarizer 300 is placed above the pixel array 200, and 16 groups of pixel groups respectively correspond to 16 linear polarization regions 311 one by one. If the center of the pixel group is just aligned with the center of the corresponding linear polarization region 311, then in Figure 7 the top view in

[0082] Please refer to Figure 8 , the polarizer 300 is placed above the pixel array 200, and 16 groups of pixel groups respectively correspond to 16 linear polarization regions 311 one by one. If the center of the pixel group is not aligned with the center of the corresponding linear polarization region 311 and there is a certain alignment error, for example Figure 8 in

[0083] the linear polarization region 311 is offset towards the upper left corner compared to the corresponding pixel group. At this time, although there is a deviation between the center of the pixel group and the center of the corresponding linear polarization region 311, it is still possible to make the orthographic projection of the pixel group located within the corresponding linear polarization region 311, so that the image sensor can obtain more comprehensive information of the target object and improve the recognition accuracy.

[0084] In some possible implementation manners of this example, N≥2. In this way, when the polarizer 300 is aligned with the pixel array 200, each linear polarization region 311 can be made to correspond to a group of pixel groups as much as possible. For example Figure 8 in Figure 9Among them, N = 2.5, and each of the 9 linearly polarized regions 311 will have the orthographic projection of a group of pixels. The difference is that some pixel groups only have one first pixel 211, some pixel groups have two first pixels 211, and some pixel groups have four first pixels 211.

[0085] In some possible implementation manners of this example, N is an integer greater than 1. In this way, when the polarizer 300 is aligned with the pixel array 200, the number of first pixels 211 in each linearly polarized region 311 can be kept as consistent as possible. For example Figure 8 As shown, N = 2, and each linearly polarized region 311 only has one first pixel 211. This makes the distribution of the first pixels 211 in the pixel array 200 relatively uniform, so as to be able to reconstruct the contour surface of the target object more accurately. In addition, it should also be understood that when N is an integer greater than 1, as N increases, in the same pixel array 200, the number of pixel groups gradually decreases. Therefore, if a higher resolution needs to be satisfied, N = 2 can be set.

[0086] Whether N is an integer greater than 1 or N ≥ 2, as long as the polarizer 300 is roughly above the pixel array 200, there must be a part of the linearly polarized regions 311 corresponding to pixel groups.

[0087] In some possible implementation manners of this example, as Figure 6 shown, in order to facilitate the correspondence between the pixel groups and the linearly polarized regions 311, multiple pixel groups can be distributed along the row direction and the column direction of the pixel array 200, and there is a second pixel 212 between adjacent two pixel groups. More specifically, in the row direction and the column direction of the pixel array 200, adjacent pixel groups are separated by the second pixel 212.

[0088] Example Two

[0089] When the area of the orthographic projection of the pixel group is smaller than the area of the linearly polarized region 311, and at least some adjacent linearly polarized regions 311 are spaced apart from each other, the two adjacent linearly polarized regions adjacent to the interval have a third center spacing in the first direction, and adjacent pixels have a second center spacing in the first direction. The third center spacing is N times the second center spacing, N > 1.

[0090] Similarly, through the condition of N > 1, a certain alignment error between the center of the pixel group and the center of the corresponding linearly polarized region can also be allowed. For example Figure 10As shown, a polarizer 300 and a pixel array 200 are shown from a top-down perspective. Among them, the polarizer 300 is located above the pixel array 200. There is a certain interval between any two linearly polarized regions 311 in the polarizer 300. When 1 < N < 2, 16 groups of pixel groups correspond to 16 linearly polarized regions 311 one by one, but the allowable alignment error is relatively small.

[0091] Example Three

[0092] When the area of the orthographic projection of the pixel group is equal to the area of the linearly polarized region, at least some adjacent linearly polarized regions are in contact with each other. The two adjacent linearly polarized regions in contact have a fourth center spacing in the first direction, and adjacent pixels have a second center spacing in the first direction. The fourth center spacing is N times the second center spacing, N = 1, and the first direction is the row or column direction of the pixel array 200.

[0093] When N = 1, the center of the pixel group (the first pixel 211) should be exactly aligned with the center of the corresponding linearly polarized region. For example Figure 11 As shown, a polarizer 300 and a pixel array 200 are shown from a top-down perspective. Among them, the polarizer 300 is located above the pixel array 200. 16 groups of pixel groups correspond to 16 linearly polarized regions 311 one by one.

[0094] Example Four

[0095] When the area of the orthographic projection of the pixel group is equal to the area of the linearly polarized region, at least some adjacent linearly polarized regions are spaced apart from each other. The two adjacent linearly polarized regions with a neighboring interval have a fifth center spacing in the first direction, and adjacent pixels have a second center spacing in the first direction. The fifth center spacing is N times the second center spacing, N is an integer greater than 1, and the first direction is the row or column direction of the pixel array 200.

[0096] The center of the pixel group (the first pixel 211) should be exactly aligned with the center of the corresponding linearly polarized region. For example Figure 12 As shown, a polarizer 300 and a pixel array 200 are shown from a top-down perspective. Among them, the polarizer 300 is located above the pixel array 200. The pixel group only includes one first pixel 211, and the area of the first pixel 211 is equal to the area of the linearly polarized region 311. Therefore, 16 groups of pixel groups correspond to 16 linearly polarized regions 311 one by one.

[0097] When decoding the light reflected by the target object, multiple minimum decoding units can be constructed, and the light reflected by the target object is decoded by the multiple minimum decoding units. Specifically, the minimum decoding unit may include at least one linearly polarized region 311 and a pixel group corresponding to each of the polarized regions. For ease of understanding, all the linearly polarized regions 311 within the minimum decoding unit are referred to as the polarization unit 310. When the polarization unit 310 includes at least two linearly polarized regions 311, their polarization directions should be different. For example Figure 3 As shown, a minimum decoding unit is shown. This minimum decoding unit includes a polarization unit 310 and four pixel groups (the first pixels A1 - A4). The polarization unit 310 includes four linearly polarized regions C1 - C4 corresponding one by one to the four first pixels A1 - A4, and the polarization directions of the four linearly polarized regions C1 - C4 are all different (as Figure 3 the dotted lines within the linearly polarized region in the figure indicate the polarization direction of the linearly polarized region, and there is an angle between any two dotted lines or the extensions of the dotted lines); and for another example Figure 4 As shown, a minimum decoding unit is shown. This minimum decoding unit includes a polarization unit 310 and two pixel groups (the pixel group composed of the first pixels A1 and A2 and the pixel group composed of the first pixels A3 and A4). The polarization unit 310 includes two linearly polarized regions C1 - C2 corresponding one by one to the two pixel groups, and the polarization directions of the two linearly polarized regions C1 and C2 are different. Of course, the minimum decoding unit may also include a polarization unit 310 and a pixel group, and this polarization unit 310 only contains one linearly polarized region 311, and this linearly polarized region 311 corresponds to this pixel group.

[0098] Taking the Figure 3 minimum decoding unit as an example: the polarization direction of the linearly polarized region C1 forms an angle of 0 degrees with the horizontal direction, so the corresponding first pixel A1 can receive linearly polarized light at 0 degrees. The polarization direction of the linearly polarized region C3 forms an angle of 45 degrees with the horizontal direction, so the corresponding first pixel A3 can receive linearly polarized light at 45 degrees. The polarization direction of the linearly polarized region C4 forms an angle of 90 degrees with the horizontal direction, so the corresponding first pixel A4 can receive linearly polarized light at 90 degrees. The polarization direction of the linearly polarized region C2 forms an angle of 135 degrees with the horizontal direction, so the corresponding first pixel A2 can receive linearly polarized light at 135 degrees.

[0099] When Figure 3 the number of the minimum decoding units shown is multiple, they form Figure 7 or Figure 8The four smallest decoding units shown are such that the four smallest decoding units can decode the light beams respectively incident into the polarization unit 310, thereby each obtaining the polarization information carried by it, and further determining the normal vectors of the four micro-elements in the target object. When the number of the smallest decoding units is large, the normal vectors of more micro-elements in the target object can be determined, and then the contour surface of the target object can be reconstructed.

[0100] Taking Figure 3 the single smallest decoding unit shown as an example: A part of the light reflected by the target object is incident into the polarization unit 310 of the smallest decoding unit, and then this part of the light is respectively incident into the four linearly polarized regions C1 - C4 in the polarization unit 310. Therefore, the light incident into each linearly polarized region will be modulated by its respective linearly polarized region to form four linearly polarized lights with different polarization directions. Then, the four linearly polarized lights are received by four pixel groups (the first pixel 211 - A4) one by one. Based on the code values of the four pixel groups, the polarization directions of the respective linearly polarized lights can be obtained, and then the polarization information of the light incident into the smallest decoding unit can be obtained, thereby obtaining the normal vector of the corresponding micro-element in the target object.

[0101] In some possible implementation manners, such as Figure 3 or Figure 5 shown, in the same polarization unit 310, the included angle between the polarization directions of any two linearly polarized regions 311 is greater than 10 degrees. This can facilitate the image sensor to obtain the polarization information carried by the incident light in a way of simultaneously receiving linearly polarized lights with multiple polarization directions.

[0102] In different implementation manners, the polarizing plate 300 can be integrated into the image sensor, so that the integration degree of the overall structure of the image sensor is higher; of course, the polarizing plate 300 can also not be integrated into the image sensor. The following will separately describe them:

[0103] First of all, each pixel can include a photosensitive unit and a unit circuit. Therefore, after the photosensitive unit arrays of all pixels in the pixel array are distributed, a photosensitive array is formed, and the unit circuits of all pixels in the pixel array are combined to form a pixel circuit. On this basis, the pixel can further include a microlens. Therefore, after the microlens arrays of all pixels in the pixel array are distributed, a microlens array is formed.

[0104] In some possible implementation manners, the polarizing plate 300 can be integrated into the image sensor. Specifically, the polarizing plate 300 and the pixel array 200 are integrated and packaged together as an image sensor, such as Figure 13As shown, the packaging levels may at least be a photosensitive array, a pixel circuit 600 (including a pixel light-shielding layer), and a polarizer 300 stacked in sequence. For another example, the packaging levels may at least also be a pixel circuit 600, a photosensitive array, and a polarizer 300 stacked in sequence. Alternatively, the packaging levels may at least also be a photosensitive array, a polarizer 300, and a pixel circuit 600 stacked in sequence. In addition, as Figure 13 shown, a microlens array 700 is stacked above the polarizer 300.

[0105] In some possible implementation manners, the polarizer 300 may not be integrated into the image sensor. Specifically, the polarizer 300 is disposed at an interval from the receiving surface of the image sensor. For example, Figure 14 shown, the light-incident surface of the microlens array 700 serves as the receiving surface of the image sensor. The polarizer 300 is located above the microlens array 700. The polarizer 300 is connected to the receiving surface of the image sensor through a support frame 810, and there is an interval between the polarizer 300 and the microlens array 700. In addition, the polarizer 300 is attached to the receiving surface of the image sensor. For example, Figure 15 shown, the polarizer 300 is attached to the upper surface of the microlens array 700 through an adhesive layer 820.

[0106] On the other hand, an embodiment of the present application provides a three-dimensional imaging device. As Figure 16 shown, the three-dimensional imaging device includes a polarization light source 400 for emitting linearly polarized light 410 and an image sensor of any of the above. The linearly polarized light 410 emitted by the polarization light source 400 forms light carrying polarization information after being reflected by a target object.

[0107] Please refer to Figure 16 . The three-dimensional imaging device includes a polarization light source 400. The light reflected by the target object comes from the polarization light source 400. The linearly polarized light 410 emitted by the polarization light source 400 propagates toward the target object and is incident on the target object. Subsequently, the light is reflected by the target object and thus carries polarization information corresponding to the contour surface of the target object. Then, the light passes through the polarizer 300 and is received by a pixel array 200.

[0108] The polarization light source 400 may directly emit linearly polarized light 410 by a light-emitting element, or may emit natural light by a light-emitting element and then form linearly polarized light 410 after being modulated by a polarizer. The present application does not limit this.

[0109] In some possible implementation manners, the polarization direction of the linearly polarized light 410 is the same as the polarization direction of at least one linearly polarized region 311. For example, the polarization direction of the linearly polarized light 410 is the same as the polarization direction of any linearly polarized region 311 in a polarization unit 310. In this way, more light can be incident on the pixel array 200, so as to provide more signal light for the pixel array 200, which helps to improve the recognition accuracy.

[0110] In some possible embodiments, the polarized light source 400 may be an infrared light source, and the wavelength band of the linearly polarized light 410 is 850 nm ± 10 nm or 940 nm ± 10 nm, such as 850 nm, 940 nm, etc.

[0111] In some possible embodiments, a band-pass filter is provided on the receiving side of the pixel array 200 of the image sensor. The band-pass wavelength band of the band-pass filter includes the emission wavelength band of the polarized light source 400, which can weaken the perception of the human eye and effectively reduce the interference of ambient light. To further improve the light utilization rate and reduce interference, the half bandwidth of the band-pass filter can be made less than 80 nm.

[0112] Another aspect of the embodiments of the present application provides a face recognition method, which includes:

[0113] S10: Obtain a polarized image through the light received by the first pixels in the pixel array, and obtain a planar image through at least the light received by the second pixels in the pixel array.

[0114] Since the polarized light received by the first pixel 211 all comes from the same linearly polarized region, the polarized light received by the first pixel 211 is all light rays with a single polarization direction. In this way, a polarized image can be generated through multiple first pixels 211. Therefore, the code value of the polarized image will contain the polarization information carried by the incident light. And since the polarization information corresponds to the contour plane of the human face 100, the contour plane of the corresponding human face 100 can be characterized by the polarized image.

[0115] Based on the fact that the light received by the second pixel 212 is relatively complex and the situation may vary, there are certain difficulties in reconstructing the contour plane of the human face 100 using the second pixel 212. However, since the light received by the second pixel 212 still comes from the reflected light of the human face 100, the second pixel 212 can be made to participate in the two-dimensional imaging of the human face 100. In this way, the planar image can contain the planar image information of the human face 100. Of course, the first pixel 211 and the second pixel 212 can both participate in the two-dimensional imaging of the human face 100, which can improve the resolution of the two-dimensional image.

[0116] By comprehensively using the first pixel 211 and the second pixel 212 of the pixel array 200, the information of the human face 100 can be obtained more comprehensively.

[0117] S20: Perform face recognition based on the polarized image and the planar image, and obtain a face recognition result. The face recognition includes: face matching and / or anti-counterfeiting recognition.

[0118] Since the polarization image can characterize the corresponding face contour plane, and the planar image can characterize the planar image information of the face 100, face recognition can be performed through the polarization image and the planar image, and then the face recognition result can be obtained. When face matching verification is included in face recognition, according to the 2D and / or 3D matching requirements, it can be performed through the polarization image and the planar image, and the face recognition result correspondingly includes the result of whether the face 100 matches. Similarly, when anti-counterfeiting recognition verification is included in face recognition, it needs to be performed with the help of the polarization image, and the face recognition result also correspondingly includes the result of whether it is a real face 100 or a forgery such as a photo, video, or silicone mold of the face 100.

[0119] Specifically, performing face recognition according to the polarization image and the planar image, and obtaining the face recognition result includes: performing face matching verification according to at least one of the polarization image and the planar image, and obtaining the face matching verification result; and / or; performing anti-counterfeiting recognition according to the polarization image, and obtaining the anti-counterfeiting recognition result.

[0120] For example: When 2D face matching verification is required, it can be performed with the help of the planar image. When 3D face matching verification is required, it can be performed with the help of the polarization image and the planar image. When anti-counterfeiting recognition is required, it can be performed with the help of the polarization image.

[0121] When performing face matching verification, the polarization image and the database polarization image (obtained by pre-recording the correct face 100) can be input into the first neural network model to obtain the result of whether the face 100 matches.

[0122] When performing face matching verification, the planar image and the database planar image (obtained by pre-recording the correct face 100) can be input into the first neural network model to obtain the result of whether the face 100 matches.

[0123] When performing face matching verification, the polarization image, the planar image, the database polarization image, and the database planar image (obtained by pre-recording the correct face 100) can be input into the first neural network model to obtain the result of whether the face 100 matches. Or, when performing face matching verification, the polarization image and the planar image can be fused to form a fused image, and then the fused image and the database fused image (formed by fusing the database polarization image and the database planar image) can be input into the first neural network model to obtain the result of whether the face 100 matches.

[0124] When performing anti-counterfeiting recognition verification, the polarization image can be input into the second neural network model to obtain the anti-counterfeiting result of whether it is a real face 100 or a forgery such as a photo, video, or silicone mold of the face 100.

[0125] In addition, when performing face recognition, it is also possible to comprehensively analyze the code values of the polarization images to obtain the polarization information carried by the light reflected by the face 100, and use this polarization information to obtain the degree to which the polarization state is changed by the face 100. By combining the light with the micro-elements in the face 100, the normal vector of the micro-element can be determined. Then, combined with the positions of the first pixels 211, the contour surface of the face 100 can be more accurately reconstructed, making the reconstructed contour surface closer to the actual contour surface of the face 100. Thus, the first pixels 211 are used to participate in the three-dimensional imaging of the face 100. Then, the face recognition result is finally obtained through the reconstructed contour surface of the face 100. Of course, in this face recognition method, face matching verification and / or anti-counterfeiting recognition verification can still be included.

[0126] The above face recognition method can be applied to any of the above image sensors or three-dimensional imaging devices.

[0127] Based on the foregoing description, when the polarizer 300 is disposed on the receiving side of the pixel array 200, the center of the positive projection of the pixel group on the plane where the polarizer 300 is located may coincide with the center of the corresponding linearly polarized region or there may be a registration error. Therefore, after the relative positions of the polarizer 300 and the pixel array 200 are fixed, it is necessary to determine which pixels in the pixel array 200 are used as the first pixels 211 and which are used as the second pixels 212. Based on this, on the other hand, an embodiment of the present application provides a pixel position determination method, and the method includes:

[0128] S30: Obtain the code value signals respectively output by multiple pixels in the pixel array. Among them, a polarizer is disposed on the receiving side of the pixel array. The polarizer has a plurality of linearly polarized regions. A test light with a preset polarization direction is incident on the pixel array after passing through the polarizer, and the preset polarization direction of the test light is the same as the polarization direction of some of the linearly polarized regions.

[0129] S40: Screen out the first pixels and the second pixels from the pixel array according to the threshold and the code value signals respectively output by the pixels. Among them, the positive projection of the first pixel on the plane where the polarizer is located is within the linearly polarized region, and the positive projection of the second pixel on the plane where the polarizer is located intersects at most partially with any linearly polarized region.

[0130] The polarization regions on the polarizer 300 can be reasonably set according to requirements. Therefore, the polarization directions of the polarization regions on the polarizer 300 are known information. Therefore, the polarization direction of the test light can be preset so that the preset polarization direction of the test light is the same as the polarization direction of some of the linearly polarized regions, which is convenient for subsequent judgment.

[0131] The test light passes through the polarizer 300 and then enters the pixel array 200. Therefore, more test light will pass through the linearly polarized region with the same polarization direction as the test light. The pixels in the pixel array 200 whose orthographic projections are completely within the linearly polarized region will receive more test light. So the code value signals output by such pixels will be very high. By setting a reasonable threshold, the pixels with code value signals higher than the threshold are screened out and used as the first pixels 211. Therefore, the orthographic projection of the first pixel 211 on the plane where the polarizer 300 is located is completely within the linearly polarized region. Since the position of the first pixel 211 is determined, based on the position information of the first pixel 211 in the pixel array 200, the position of the second pixel 212 can be determined.

[0132] Especially when the polarization directions of all the polarized regions in the polarizer 300 are the same, all the first pixels 211 can be screened out at one time by the above method, and the remaining pixels in the pixel array 200 are used as the second pixels 212.

[0133] Optionally, when among multiple linearly polarized regions, the polarization directions of some linearly polarized regions are different, screening out the first pixels and the second pixels from the pixel array according to the threshold and the code value signals output by each pixel includes:

[0134] S41: Screen out some first pixels from the pixel array according to the threshold and the code value signals output by each pixel.

[0135] S42: Screen out another part of the first pixels and the second pixels from the pixel array according to the position information of some first pixels in the pixel array, the arrangement information of multiple linearly polarized regions, and the size relationship between the linearly polarized regions and the pixels.

[0136] First, still screen out the pixels with code value signals higher than the threshold according to the threshold and use them as some first pixels 211. The positions of these first pixels 211 in the pixel array 200 are determined. Then, based on the known positions of the first pixels 211, combined with the arrangement and size information of multiple linearly polarized regions, the position information of the remaining other part of the first pixels 211 is determined, and finally the position information of the second pixels 212 is obtained.

[0137] For example Figure 7 or Figure 8, four linearly polarized regions form a polarization unit 310. The polarization directions of the four linearly polarized regions are different from each other. For example, the angles between the polarization directions and the horizontal direction are 0 degrees, 45 degrees, 90 degrees, and 135 degrees respectively. Then, they are arranged in a cycle with this polarization unit 310, and the area of the linearly polarized region is larger than the area of the pixel. Since N = 2, among the four pixels arranged in a square layout, there must be one belonging to the first pixel 211. The preset polarization direction of the test light can be 0 degrees. In this way, through the code value signal output by the pixel array 200 and combined with the threshold, the position information of the first pixel 211 for receiving 0-degree polarized light in each polarization unit 310 in the pixel array 200 can be determined first. Based on the position information of the first pixel 211 for receiving 0-degree polarized light and combined with the arrangement of the polarization directions of the four linearly polarized regions in each polarization unit 310, for example, in the clockwise direction are 0 degrees, 45 degrees, 90 degrees, and 135 degrees, the position information of the three first pixels 211 corresponding to the remaining three linearly polarized regions in the polarization unit 310 can be determined. Thus, the position information of all the first pixels 211 in the pixel array 200 is obtained, and the remaining pixels are used as the second pixels 212.

[0138] In yet another aspect of the embodiments of the present application, an electronic device is provided, including a device main body and an image sensor of any of the above, and the image sensor is located in the device main body;

[0139] Or, it includes a device main body and a three-dimensional imaging device of any of the above, and the three-dimensional imaging device is located in the device main body.

[0140] The electronic device can perform two-dimensional and three-dimensional imaging on the target object, so as to obtain more comprehensive information about the target object, which helps to improve the recognition accuracy.

[0141] The electronic device can specifically be a mobile phone, a tablet computer, a television, a laptop computer, a smart home device (such as a smart air conditioner, a smart refrigerator, a smart speaker, a smart light, or a smart curtain, etc.), a wearable electronic device, a vehicle-mounted device (also known as a car computer), a virtual reality device, etc. The embodiments of the present application do not make any restrictions on this.

[0142] The above are only the preferred embodiments of the present application and are not used to limit the present application. For those skilled in the art, the present application can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An image sensor, characterized in that, It includes a pixel array, and a polarizer is provided on the receiving side of the pixel array. The polarizer has a plurality of linearly polarized regions; The pixel array includes a plurality of pixels distributed in an array. Each pixel has a positive projection on the plane where the polarizer is located. The pixels whose positive projections are all located within the linearly polarized region are used as first pixels, and the pixels whose positive projections intersect at most partially with any one of the linearly polarized regions are used as second pixels; The first pixels and the second pixels are used to receive light carrying polarization information, and the polarization information corresponds to the contour surface of the target object.

2. The image sensor according to claim 1, wherein The first pixels whose positive projections are all located within the same linearly polarized region form a group of pixel groups, and each pixel group includes at least one of the first pixels. The area of the positive projection of the pixel group on the plane where the polarizer is located is less than or equal to the area of the linearly polarized region.

3. The image sensor according to claim 2, characterized in that, Among the plurality of linearly polarized regions, at least some adjacent linearly polarized regions are adjacent to each other or spaced apart.

4. The image sensor according to claim 3, wherein, Adjacent two linearly polarized regions have a first center spacing in a first direction, and adjacent two pixels have a second center spacing in the first direction. The first center spacing is N times the second center spacing, N≥1. The pixel array is distributed in a matrix, and the first direction is the row or column direction of the pixel array.

5. The image sensor according to claim 4, characterized in that, The area of the positive projection of the pixel group is less than the area of the linearly polarized region, and at least some adjacent linearly polarized regions are adjacent to each other, N>1.

6. The image sensor according to claim 5, wherein N≥2, or N is an integer greater than 1.

7. The image sensor according to any one of claims 2 to 6, characterized in that, A plurality of the pixel groups are distributed along the row direction and the column direction of the pixel array, and there are second pixels between adjacent two pixel groups.

8. The image sensor according to any one of claims 1 to 6, characterized in that, Among the plurality of linearly polarized regions, at least one linearly polarized region forms a polarization unit. When the polarization unit includes at least two linearly polarized regions, the polarization directions of at least two linearly polarized regions are different from each other.

9. The image sensor according to claim 8, characterized in that, When the polarization unit includes at least two linearly polarized regions, in the same polarization unit, the included angle between the polarization directions of any two linearly polarized regions is greater than 10 degrees.

10. The image sensor according to any one of claims 1 to 6, characterized in that, The polarizer is integrated in the image sensor.

11. The image sensor according to claim 10, wherein, The pixel includes a photosensitive unit and a unit circuit. The photosensitive units of a plurality of pixels are distributed in an array to form a photosensitive array, and the unit circuits of a plurality of pixels form a pixel circuit: The pixel circuit is located between the photosensitive array and the polarizer; The pixel circuit is located on the side of the photosensitive array away from the polarizer; Or, the pixel circuit is located on the side of the polarizer away from the photosensitive array.

12. The image sensor according to any one of claims 1 to 6, characterized in that, The polarizer is spaced from the receiving surface of the image sensor, or the polarizer is attached to the receiving surface of the image sensor.

13. The image sensor according to claim 12, wherein, When the polarizer is attached to the receiving surface of the image sensor, the pixel includes a photosensitive unit and a microlens. The photosensitive units of a plurality of pixels are distributed in an array to form a photosensitive array, and the microlenses of a plurality of pixels are distributed in an array to form a microlens array. The microlens array is located between the photosensitive array and the polarizer, and the polarizer is attached to the surface of the microlens array.

14. A three-dimensional imaging device, characterized in that, Comprising a polarization light source for emitting linearly polarized light and an image sensor as described in any one of claims 1 to 13, the linearly polarized light emitted by the polarization light source forms a light ray carrying polarization information after being reflected by the target object.

15. The three-dimensional imaging device according to claim 14, wherein, The image sensor includes a polarizer having a plurality of linearly polarized regions, and the polarization direction of the linearly polarized light is the same as the polarization direction of at least one of the linearly polarized regions.

16. The three-dimensional imaging device according to claim 14, characterized in that, The wavelength band of the linearly polarized light is 850nm ± 10nm or 940nm ± 10nm.

17. The three-dimensional imaging device according to claim 14, characterized in that, A band-pass filter is provided on the receiving side of the pixel array of the image sensor. The band-pass wavelength band of the band-pass filter includes the light-emitting wavelength band of the polarization light source, and the half bandwidth of the band-pass filter is less than 80nm.

18. An electronic device, characterized in that, Comprising a device body and an image sensor as described in any one of claims 1 to 13, the image sensor is located in the device body; Or, comprising a device body and a three-dimensional imaging device as described in any one of claims 14 to 17, the three-dimensional imaging device is located in the device body.

Images