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 photosensitive array, a polarization element is arranged on the receiving side of the photosensitive array, the polarization element is provided with a plurality of polarization unit groups, and each polarization unit group comprises at least one polarization unit with a polarization direction. The polarization directions of the polarization units in the same polarization unit group are the same or different, light reflected by a target object carries polarization information corresponding to the contour surface of the target object to enter the polarization element, and the light is modulated by the polarization unit of each polarization unit group to form at least one first linearly polarized light; and then receiving the first linearly polarized light and forming an image. By comprehensively analyzing the formed image and the position of each photosensitive unit in the photosensitive array, the contour surface of the target object can be accurately reconstructed, and the recognition precision can be improved.

Description

Technical Field

[0001] This application relates to the field of biometric technologies, and in particular, 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 accordingly. 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 photosensitive array, a polarization element is arranged on the receiving side of the photosensitive array, the polarization element has a plurality of polarization unit groups, each polarization unit group includes at least one polarization unit with a polarization direction, and the polarization directions of the polarization units in the same polarization unit group are the same or different;

[0007] The light reflected by the target carries polarization information corresponding to the contour surface of the target and is incident on the polarization element, and at least one first linearly polarized light is formed by modulating the polarization units of each polarization unit group, and the at least one first linearly polarized light is respectively incident on the photosensitive array.

[0008] Optionally, the photosensitive array includes a plurality of photosensitive unit groups, the photosensitive unit groups correspond to the polarization unit groups one by one, each photosensitive unit group includes at least one subgroup, the subgroups in the photosensitive unit group correspond to the polarization units in the corresponding polarization unit group one by one, and each subgroup is used to receive the first linearly polarized light emitted by the corresponding polarization unit, and the subgroup includes at least one photosensitive unit.

[0009] Optionally, each polarization unit group includes at least two polarization units with polarization directions, and the polarization directions of the polarization units within the same polarization unit group are different.

[0010] Optionally, within the same polarization unit group, the included angle between the polarization directions of any two polarization units is greater than 10 degrees.

[0011] Optionally, the polarization element includes a metal layer, the polarization unit is a wire grid structure on the metal layer, the image sensor further includes a pixel circuit having a metal wiring layer, and the metal wiring layer of the pixel circuit and the metal layer are separately disposed on the same side or opposite sides of the photosensitive array.

[0012] Optionally, the polarization element is integrated within the image sensor.

[0013] Optionally, the image sensor further includes a pixel circuit;

[0014] The pixel circuit is located between the photosensitive array and the polarization element;

[0015] The pixel circuit is located on a side of the photosensitive array facing away from the polarization element;

[0016] Alternatively, the pixel circuit is located on a side of the polarization element facing away from the photosensitive array.

[0017] Optionally, the polarization element further includes a substrate, the polarization units of the polarization element are attached to the substrate, and the polarization element and the receiving surface of the image sensor are spaced apart.

[0018] Optionally, the polarization element is attached to the receiving surface of the image sensor.

[0019] Optionally, when the polarization element is attached to the receiving surface of the image sensor, the image sensor further includes a microlens array located between the photosensitive array and the polarization element, and the polarization element is attached to the surface of the microlens array.

[0020] Optionally, the photosensitive array includes a plurality of photosensitive unit groups, each photosensitive unit group includes a plurality of subgroups, and at least some of the photosensitive unit groups further include a vacant area located between the plurality of subgroups, and the vacant area is a photosensitive area or a non - photosensitive area.

[0021] On the other hand, an embodiment of the present application provides a three - dimensional imaging device, including the image sensor of any one of the above, and the three - dimensional imaging device further includes a polarization light source, and the second linearly polarized light emitted by the polarization light source is reflected by the target object to carry polarization information corresponding to the contour surface of the target object.

[0022] Optionally, the polarization direction of the second linearly polarized light is the same as the polarization direction of any one of the polarization units in the polarization unit group of the image sensor.

[0023] On the other hand, an embodiment of the present application provides an electronic device, including a device body and any one of the above image sensors, and the image sensor is located in the device body;

[0024] Or, it includes a device body and any one of the above three-dimensional imaging devices, and the three-dimensional imaging device is located in the device body.

[0025] The beneficial effects of the present application include:

[0026] The present application provides an image sensor, a three-dimensional imaging device and an electronic device, including a photosensitive array. A polarization element is arranged on the receiving side of the photosensitive array. The polarization element has a plurality of polarization unit groups. Each polarization unit group includes at least one polarization unit with a polarization direction. The polarization directions of the polarization units in the same polarization unit group are the same or different. The light reflected by the target object carries polarization information corresponding to the contour surface of the target object and is incident on the polarization element, and at least one first linearly polarized light is formed through the modulation of the polarization units of each polarization unit group, and then these first linearly polarized lights are received and an image is formed. By comprehensively analyzing the formed image and the positions of the photosensitive units in the photosensitive array, the contour surface of the target object can be reconstructed more accurately, which helps to improve the recognition accuracy. Description of the Drawings

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required to be used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as a limitation of the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0028] Figure 1 One of the schematic structural diagrams of an image sensor provided by an embodiment of the present application;

[0029] Figure 2 One of the schematic diagrams of the corresponding relationship between a polarization element and a photosensitive array provided by an embodiment of the present application;

[0030] Figure 3 Two of the schematic diagrams of the corresponding relationship between a polarization element and a photosensitive array provided by an embodiment of the present application;

[0031] Figure 4 Three of the schematic diagrams of the corresponding relationship between a polarization element and a photosensitive array provided by an embodiment of the present application;

[0032] Figure 5 One of the schematic structural diagrams of a three-dimensional imaging device provided by an embodiment of the present application;

[0033] Figure 6It is the second schematic structural diagram of an image sensor provided by an embodiment of the present application;

[0034] Figure 7 It is the third schematic structural diagram of an image sensor provided by an embodiment of the present application.

[0035] Icons: 100 - human face; 200 - photosensitive array; 210 - photosensitive unit group; 211 - subgroup; 2111 - photosensitive unit; 2112 - vacant area; 300 - polarization element; 310 - polarization unit group; 311 - polarization unit; 400 - non-polarized light source; 410 - second linearly polarized light; 500 - linear polarizer; 600 - pixel circuit; 700 - microlens array. Specific embodiments

[0036] 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 may be combined with each other, and the combined embodiments are still within the protection scope of the present application.

[0037] 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 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, and thus cannot be construed as a limitation to the present application. In addition, the terms "first", "second", "third", etc. are only used for descriptive distinction and cannot be construed as indicating or implying relative importance.

[0038] In the description of the present application, it should also be noted that unless otherwise clearly specified and limited, the terms "set", "installed", "connected", "connected" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected, or indirectly connected through an intermediate medium, and it may be the communication inside two elements. 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.

[0039] In order to optimize the imaging effect and improve the recognition accuracy, an embodiment of the present application provides an image sensor. The image sensor can receive the light beam reflected by the target object. During the process of the image sensor receiving the light beam, the incident light beam is modulated in sub-regions to form a first linearly polarized light with different polarization directions, and then these first linearly polarized lights are received simultaneously to form an image. By comprehensively analyzing the formed image and the positions of the photosensitive units in the photosensitive array, the contour surface of the target object can be reconstructed more accurately, which helps to improve the recognition accuracy. Of course, for the sake of understanding, the embodiments of the present application will be described below with reference to the accompanying drawings.

[0040] Please refer to Figure 1 , an embodiment of the present application provides an image sensor. The image sensor has a photosensitive array 200, and a polarization element 300 is arranged on the receiving side of the photosensitive array 200, that is, the polarization element 300 is located in the optical path between the target object and the photosensitive array 200, so that the light reflected by the target object can first pass through the polarization element 300 and then be received and imaged by the photosensitive array 200.

[0041] During the process that the light is incident on the target object and reflected by the target object, since the degree of change in the polarization state of the 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.

[0042] In order to obtain this polarization information to 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 sub-regions, so as to comprehensively analyze the modulated light to obtain this polarization information. Specifically, please refer to Figure 2 , the polarization element 300 has a plurality of polarization unit groups 310 ( Figure 2 only two polarization unit groups 310 of the polarization element 300 are shown in, and the number of the polarization unit groups 310 is not limited in practice. When the number of the polarization unit groups 310 is large, the resolution of the image sensor will correspondingly increase), each polarization unit group 310 includes at least one polarization unit 311, and each polarization unit 311 has a polarization direction. The polarization directions of the polarization units 311 within the same polarization unit group 310 can be the same or different. For example, when the polarization unit group 310 includes one polarization unit 311, the polarization unit 311 within the polarization unit group 310 has one polarization direction; when the polarization unit group 310 includes two polarization units 311, the polarization directions of these two polarization units 311 can be the same or different; when the polarization unit group 310 includes more than three polarization units 311, the polarization directions of all the polarization units 311 can be different from each other (for example Figure 2The dotted lines within the polarization unit 311 indicate the polarization directions of the polarization unit 311. There is an angle between any two dotted lines or the extensions of the dotted lines. Figure 2 The shown polarization unit group 310 includes four polarization units 311 with different polarization directions. It is also possible that all the polarization units 311 have the same polarization direction, or some of the polarization units 311 have the same polarization direction while the other part of the polarization units 311 have different polarization directions.

[0043] First, for the convenience of explanation, define: all the light rays that can be incident on the polarization element 300 after being reflected by the target object are collectively referred to as the first light beam. Then, based on the different positions where the light rays in the first light beam are incident on the polarization element 300, the first light beam will be scattered and incident on some or all of the polarization unit groups 310 in the polarization element 300. Continue to define: all the light rays incident within a single polarization unit group 310 are called the first sub-beam. Therefore, the first light beam contains multiple first sub-beams.

[0044] The first sub-beam is modulated by the polarization unit 311 in the polarization unit group 310 into at least one first linearly polarized light. After the photosensitive array 200 receives at least one first linearly polarized light emitted by the polarization unit group 310, based on the code value of the first linearly polarized light, the polarization direction of the first linearly polarized light can be obtained, and then the polarization information of the first sub-beam incident on the polarization unit group 310 can be obtained. According to this principle, extended to all the first sub-beams, the polarization information of all the first sub-beams can be obtained. Then, using the polarization information, the degree of change of the polarization state of the first sub-beam by the target object is obtained, combined with the micro-elements in the target object corresponding to the first sub-beam, the normal vector of the micro-element is determined. Based on this, combined with the positions of the photosensitive units 2111 in the photosensitive array 200, 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.

[0045] In the scenario of face 100 recognition, when it is necessary to input the target face 100, the aforementioned image sensor can be used to make the input information closer to the actual contour surface of the target face 100. In this way, when determining the information of the face 100 to be recognized collected during the subsequent recognition process based on the input information, it is possible to more accurately determine whether the face 100 to be recognized is the target face 100. Of course, this includes the verification of face 100 matching and / or the verification of anti-counterfeiting recognition. When the face 100 recognition includes the verification of face 100 matching, the face 100 recognition result correspondingly includes the result of whether the face 100 matches. Similarly, when the face 100 recognition includes the verification of anti-counterfeiting recognition, the face 100 recognition result also correspondingly includes the result of whether it is a real face 100 or a forgery such as a photo, video, or face 100 silicone mold. When collecting the information of the face 100 to be recognized, the aforementioned image sensor can also make the collected information of the face 100 to be recognized closer to the actual contour surface of the face 100 to be recognized, thereby improving the accuracy of recognition.

[0046] In order to better obtain the polarization information to provide data support for reconstructing the contour surface of the target object, the image sensor can be enabled to decode the light reflected by the target object, thereby forming the first linearly polarized light with multiple polarization directions to represent the polarization information carried by the incident light. In this way, the image sensor can obtain the polarization information carried by the incident light by simultaneously receiving the first linearly polarized light with multiple polarization directions. Specifically, each polarization unit group 310 includes at least two polarization units 311 with polarization directions. The polarization directions of the polarization units 311 within the same polarization unit group 310 are different. In this way, each polarization unit 311 can modulate the incident light into the first linearly polarized light consistent with its own polarization direction.

[0047] For better understanding, first take a single polarization unit group 310 as an example. The first split beam incident on this polarization unit group 310 is further refined into at least two first sub-beams according to the differences in the polarization units 311 in the polarization unit group 310. Each first sub-beam is incident on one polarization unit 311 correspondingly. After being modulated by the corresponding polarization unit 311, each first sub-beam will form a first linearly polarized light consistent with the polarization direction of the polarization unit 311. Therefore, the first split beam will be modulated into at least two first linearly polarized lights in sub-regions by at least two polarization units 311 within the polarization unit group 310. The polarization directions of the at least two first linearly polarized lights are different from each other. After the photosensitive array 200 receives the first linearly polarized lights emitted by the polarization unit group 310, based on the code values of each first linearly polarized light, the polarization directions of each first linearly polarized light can be obtained, and then the polarization information of the first split beam incident on the polarization unit group 310 can be obtained. According to this principle, when extended to all first split beams, the polarization information of all first split beams can be obtained. Then, using the polarization information, the degree of change of the polarization state of the first split beam by the target object is obtained. Combining with the micro-elements in the target object corresponding to the first split beam, the normal vector of the micro-element is determined. Based on this and the positions of each photosensitive unit 2111 in the photosensitive array 200, 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.

[0048] The relationship between the first split beam, the first sub-beams, and the first linearly polarized lights is specifically described by way of example as follows: For example Figure 2 in the figure, the left polarization unit group includes polarization units C1, C2, C3, and C4. If light is incident on all four polarization units, the first split beam incident on this polarization unit group is refined into four first sub-beams B1, B2, B3, and B4. And the first sub-beam B1 is incident on the polarization unit C1, the first sub-beam B2 is incident on the polarization unit C2, the first sub-beam B3 is incident on the polarization unit C3, etc. Subsequently, the first sub-beam B1 is modulated by the polarization unit C1 to form the first linearly polarized light B11, the first sub-beam B2 is modulated by the polarization unit C2 to form the first linearly polarized light B21, the first sub-beam B3 is modulated by the polarization unit C3 to form the first linearly polarized light B31, and the first sub-beam B4 is modulated by the polarization unit C4 to form the first linearly polarized light B41. Then, the first linearly polarized lights B11, B21, B31, and B41 are received and imaged by the photosensitive array.

[0049] It should be understood that the target object in this application can be Figure 1 the human face 100 in the figure, a part of the human face 100 (such as the cheek, 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.

[0050] To facilitate determining the position where linearly polarized light is incident on the photosensitive array 200, the photosensitive array 200 can be made to correspond to the polarization unit group 310 in the polarization element 300 in the manner of the photosensitive unit group 210. Specifically, please refer to Figure 3 or Figure 4 , the photosensitive array 200 has multiple photosensitive unit groups 210, and the photosensitive unit groups 210 correspond one-to-one with the polarization unit groups 310. That is to say, all the first linearly polarized light emitted from each polarization unit group 310 will be received by its corresponding photosensitive unit group 210. On this basis, the relationship between the polarization unit group 310 and the photosensitive unit group 210 can be further refined. For example: each photosensitive unit group 210 further includes multiple subgroups 211, so that in the corresponding photosensitive unit group 210 and polarization unit group 310, the subgroups 211 correspond one-to-one with the polarization units 311. That is to say, the first linearly polarized light emitted from each polarization unit 311 will be received by its corresponding subgroup 211. In this way, based on the position of the subgroup 211, the incident position of the first linearly polarized light can be obtained.

[0051] To better understand the above corresponding relationship between the photosensitive unit group 210 and the polarization unit group 310, take Figure 3 the example shown for illustration: Figure 3 shows two polarization unit groups 310 of the polarization element 300. Each polarization unit group 310 includes four polarization units 311. At the same time, two photosensitive unit groups 210 of the photosensitive array 200 are also shown, and each photosensitive unit group 210 also includes four subgroups 211. The left polarization unit group 310 corresponds to the left photosensitive unit group 210, and the right polarization unit group 310 corresponds to the right photosensitive unit group 210. For the left polarization unit group and the left photosensitive unit group: the left polarization unit group includes four polarization units C1, C2, C3, and C4, and the left photosensitive unit group includes four subgroups A1, A2, A3, and A4. The polarization unit C1 corresponds to the subgroup A1, the polarization unit C2 corresponds to the subgroup A2, the polarization unit C3 corresponds to the subgroup A3, and the polarization unit C4 corresponds to the subgroup A4. Therefore, the first linearly polarized light B11 emitted from the polarization unit C1 will be incident on the subgroup A1, the first linearly polarized light B21 emitted from the polarization unit C2 will be incident on the subgroup A2, the first linearly polarized light B31 emitted from the polarization unit C3 will be incident on the subgroup A3, etc.

[0052] The subgroup 211 is composed of photosensitive units 2111. Specifically, the subgroup 211 includes at least one photosensitive unit 2111. That is to say, the first linearly polarized light emitted from the polarization unit 311 can be received by at least one photosensitive unit 2111 in its corresponding subgroup 211. For better understanding, the following takes Figure 3 and Figure 4For example, the description is as follows:

[0053] Please refer to Figure 3 , Figure 3 In the subgroup 211 shown in Figure 3 , it only includes one photosensitive unit 2111. At this time, the first linearly polarized light B11 emitted by the polarization unit C1 will be received by one photosensitive unit within the subgroup A1, and the same applies to other polarization units.

[0054] Please refer to Figure 4 , Figure 4 In the subgroup 211 shown in Figure 4 , it consists of two photosensitive units 2111. At this time, the first linearly polarized light B11 emitted by the polarization unit C1 will be received by one or two photosensitive units 2111 within the subgroup A1, and the same applies to other polarization units.

[0055] Similarly, when the subgroup 211 includes other numbers of photosensitive units 2111, the reception situation of the first linearly polarized light emitted by the polarization unit 311 can be determined.

[0056] It should be understood that the image sensor has pixels, and the relationship between the pixels and the photosensitive unit 2111 in this application is as follows: one pixel includes one photosensitive unit 2111. Of course, in addition to the photosensitive unit 2111, the pixel may also have other structures such as a circuit for controlling the photosensitive unit and a microlens.

[0057] In some possible implementation manners, as shown in Figure 2 , Figure 3 or Figure 4 In the same polarization unit group 310, the included angle between the polarization directions of any two polarization units 311 is greater than 10 degrees. This can facilitate the image sensor to obtain the polarization information carried by the incident light in a manner of simultaneously receiving the first linearly polarized light of multiple polarization directions. As shown in Figure 2 , Figure 3 or Figure 4 The polarization directions of the polarization unit C1 and the polarization unit C2 have an included angle θ1, and the polarization directions of the polarization unit C2 and the polarization unit C4 have an included angle θ2, and both the included angles θ1 and θ2 are greater than 10 degrees. For example, in the example shown in Figure 2 assuming that the polarization direction of the polarization unit C1 is 0 degrees, then the polarization direction of the polarization unit C2 is 45 degrees, the polarization direction of the polarization unit C3 is 90 degrees, and the polarization direction of the polarization unit C4 is 135 degrees. Therefore, the included angle θ1 is 45 degrees and the included angle θ2 is 90 degrees. Of course, it is not limited to this.

[0058] In some possible embodiments, the polarization element 300 includes a metal layer, and the polarization unit 311 is a wire grid structure on the metal layer. Among them, the image sensor includes a pixel circuit, and the pixel circuit has a metal wiring layer. The metal layer can be reused with the metal wiring layer of the pixel circuit or not. For example, when the metal layer is not reused with the metal wiring layer of the pixel circuit, the metal wiring layer of the pixel circuit and the metal layer are separately arranged on the same side or opposite sides of the photosensitive array 200. In this way, the metal wiring layer of the pixel circuit and the metal layer are arranged on different layers. For example, both the metal layer and the metal wiring layer of the pixel circuit can be located on the receiving side of the photosensitive array 200, but they are on different layers. Another example is that the metal wiring layer of the pixel circuit is located on the back side of the photosensitive array 200 (the side away from the receiving side), and the metal layer is located on the receiving side of the photosensitive array 200.

[0059] In different embodiments, the polarization element 300 can be integrated into the image sensor, that is, the image sensor includes the polarization element 300, so that the integration degree of the overall structure of the image sensor is higher; of course, the polarization element 300 can also not be integrated into the image sensor. The following will explain them separately:

[0060] In some possible embodiments, the polarization element 300 can be integrated into the image sensor. Specifically, the polarization element 300 and the photosensitive array 200 are integrated and packaged together as an image sensor (the image sensor may also include other structures), such as Figure 6 As shown, the packaging levels can be at least the photosensitive array 200, the pixel circuit 600 (including the pixel light-shielding layer), and the polarization element 300 stacked in sequence. Another example is that the packaging levels can be at least the pixel circuit 600, the photosensitive array 200, and the polarization element 300 stacked in sequence. In addition, as Figure 6 shown, there can also be a microlens array 700 stacked above the polarization element 300 in the image sensor. The microlenses in the microlens array 700 can correspond one-to-one with the photosensitive units 2111 in the photosensitive array 200. Or, the packaging levels can be at least the photosensitive array 200, the polarization element 300, and the pixel circuit 600 stacked in sequence.

[0061] In some possible embodiments, the polarization element 300 may not be integrated into the image sensor. Specifically, the polarization element 300 is spaced apart from the receiving surface of the image sensor. At this time, the polarization element 300 may further include a substrate (a light-transmitting substrate, such as glass, etc.), and all the polarization units of the polarization element 300 are attached to the surface of the substrate, so as to facilitate the substrate to carry the polarization element 300. Specifically, for example, the light-incident surface of the microlens array 700 serves as the receiving surface of the image sensor, and the polarization element 300 and the substrate are both located above the microlens array 700, and the whole formed by the polarization element 300 and the substrate is spaced apart from the microlens array; in addition, the polarization element 300 is attached to the receiving surface of the image sensor, for example, the polarization element 300 is attached to the upper surface of the microlens array 700.

[0062] It should be understood that, compared with the method in which the polarization element 300 can be integrated into the image sensor, when the polarization element 300 is spaced apart from the receiving surface of the image sensor or the polarization element 300 is attached to the receiving surface of the image sensor, the distance between the polarization element 300 and the photosensitive array 200 is relatively far.

[0063] As Figure 7 shown, since the light beam gradually converges during the process of incident on the image sensor (for example, an imaging lens group is arranged on the light-incident side of the image sensor), when the polarization element 300 is far from the photosensitive array 200, the area of the polarization unit 311 needs to be larger than the area of the subgroup 211, so that the polarization unit 311 can modulate as much as possible the light that originally incident on the subgroup 211. At this time, for the convenience of layout, at least part of the photosensitive unit group 210 further includes a vacant area 2112 located between multiple subgroups 211, so as to use the area of the vacant area 2112 to accommodate the polarization unit 311 with a larger area, so that the polarization unit 311 and the subgroup 211 can be as vertically corresponding as possible.

[0064] In different embodiments, the vacant area 2112 may be a photosensitive area or a non-photosensitive area. When the vacant area 2112 is a photosensitive area, the photosensitive area can still sense light, and a plurality of photosensitive units can be arranged therein. However, since the light incident on this photosensitive area may come from different polarization units 311, the 2D information of the target object can be sensed through this photosensitive area, for example, only 2D imaging is performed; when the vacant area 2112 is a non-photosensitive area, this area can be made vacant, for example, it can be used to arrange other components or for wiring.

[0065] Another aspect of the embodiments of the present application provides a three-dimensional imaging device, as Figure 5As shown, the three-dimensional imaging device further includes a polarized light source and the image sensor of any of the above. The polarized light source can emit a second linearly polarized light 410. The second linearly polarized light 410 forms a light ray carrying polarization information after being reflected by the target object. This light ray enters the polarization element 300 through the aforementioned optical path, and then is modulated into a first linearly polarized light and received by the photosensitive array 200.

[0066] In order to conveniently utilize the polarization information to obtain the degree of change of the polarization state of the first beam split by the target object, the light ray incident on the target object can be a polarized light with a predictable polarization state, such as linearly, elliptically or circularly polarized light, etc. Therefore, the light ray incident on the target object can be directly emitted by the polarized light source, or can be formed by the cooperation of an unpolarized light source 400 and a linear polarizer 500. For example: Figure 5 As shown, the unpolarized light source 400 cooperates with the linear polarizer 500. The linear polarizer 500 is arranged on the light-emitting side of the unpolarized light source 400. In this way, the light ray emitted by the unpolarized light source 400 is modulated by the linear polarizer 500 to form a second linearly polarized light and enters the target object. Since the light ray incident on the surface of the target object is in a linearly polarized state, its polarization state is relatively simple, and it is more convenient to obtain the degree of change of the polarization state of the first beam split by the target object, which helps to simplify the difficulty of data processing and reduce the power consumption of data processing.

[0067] In some possible implementation manners, the polarization direction of the linear polarizer 500 is the same as the polarization direction of any polarization unit 311 in the polarization unit group 310. In this way, more light rays can enter the photosensitive array 200, thereby providing more signal light for the photosensitive array 200, which helps to improve the accuracy of recognition.

[0068] Optionally, the polarized light source in the present application can be an infrared light source or a visible light source. Among them, the light ray emitted by the infrared light source is a light ray in the infrared band, and the light ray emitted by the visible light source is a light ray in the visible light band. When the polarized light source is an infrared light source, when used in cooperation with a filter, it can not only weaken the perception of the human eye, but also effectively reduce the interference of ambient light.

[0069] Another aspect of the embodiments of the present application provides an electronic device, including a device main body and the image sensor of any of the above, and the image sensor is located in the device main body;

[0070] Or, it includes a device main body and any of the above three-dimensional imaging devices, and the three-dimensional imaging device is located in the device main body.

[0071] 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 called a car machine), a virtual reality device, etc. The embodiments of the present application do not make any restrictions on this.

[0072] The above are only the preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included within the protection scope of the present application.

Claims

1. An image sensor, characterized in that, A photosensitive array is included, a polarization element is arranged on the receiving side of the photosensitive array, the polarization element has a plurality of polarization unit groups, each of the polarization unit groups includes at least one polarization unit with a polarization direction, and the polarization directions of the polarization units in the same polarization unit group are the same or different; The light reflected by the target carries polarization information corresponding to the contour surface of the target and enters the polarization element, and is modulated by the polarization unit of each polarization unit group to form at least one first linear polarized light, and the at least one first linear polarized light enters the photosensitive array respectively.

2. The image sensor according to claim 1, characterized in that, The photosensitive array includes a plurality of photosensitive unit groups, and the photosensitive unit groups correspond one-to-one to the polarization unit groups. Each of the photosensitive unit groups includes at least one subgroup. The subgroups within the photosensitive unit groups correspond one-to-one to the polarization units within the corresponding polarization unit groups. Each subgroup is used to receive the first linear polarized light emitted by the corresponding polarization unit, and the subgroup includes at least one photosensitive unit.

3. The image sensor according to claim 1 or 2, characterized in that, Each of the polarization unit groups includes at least two polarization units having polarization directions, and the polarization directions of the polarization units in the same polarization unit group are different.

4. The image sensor according to claim 3, wherein, In the same polarization unit group, the included angle between the polarization directions of any two polarization units is greater than 10 degrees.

5. The image sensor according to claim 1 or 2, wherein The polarization element includes a metal layer, the polarization unit is a wire grid structure on the metal layer, and the image sensor also includes a pixel circuit having a metal wiring layer, and the metal wiring layer of the pixel circuit is separately arranged on the same side or opposite side of the photosensitive array as the metal layer.

6. The image sensor according to claim 1 or 2, wherein The polarization element is integrated into the image sensor.

7. The image sensor according to claim 6, wherein The image sensor further includes a pixel circuit; The pixel circuit is located between the photosensitive array and the polarization element; The pixel circuit is located on a side of the photosensitive array away from the polarization element; Alternatively, the pixel circuit is located on a side of the polarization element facing away from the photosensitive array.

8. The image sensor according to claim 1 or 2, wherein The polarization element is attached to the receiving surface of the image sensor, or the polarization element further includes a substrate, the polarization unit of the polarization element is attached to the substrate, and the polarization element is spaced apart from the receiving surface of the image sensor.

9. The image sensor according to claim 8, wherein, When the polarizing element is attached to the receiving surface of the image sensor, the image sensor further comprises a microlens array located between the photosensitive array and the polarizing element, and the polarizing element is attached to the surface of the microlens array.

10. The image sensor according to claim 8, characterized in that, The photosensitive array includes a plurality of photosensitive unit groups, each of the photosensitive unit groups includes a plurality of sub-groups, and at least some of the photosensitive unit groups further include vacant areas between the plurality of sub-groups, wherein the vacant areas are photosensitive areas or non-photosensitive areas.

11. A three-dimensional imaging device, characterized in that, Comprising the image sensor as claimed in any one of claims 1 to 10, the three-dimensional imaging device also includes a polarized light source, and the second linear polarized light emitted by the polarized light source is reflected by the target object to carry polarization information corresponding to the contour surface of the target object.

12. The three-dimensional imaging device according to claim 11, wherein The polarization direction of the second linearly polarized light is the same as the polarization direction of any polarization unit in the polarization unit group of the image sensor.

13. An electronic device, characterized in that, Comprising a device body and an image sensor as described in any one of claims 1 to 10, the image sensor being located in the device body; Or, comprising a device body and a three-dimensional imaging device as described in claim 11 or 12, the three-dimensional imaging device being located in the device body.

Images