Light source, image receiver, image acquisition device and electronic equipment

Abstract

The utility model provides a light source, an image receiver, an image acquisition device and electronic equipment, and relates to the technical field of biological recognition, the light source comprises a light-emitting element with at least two polarization structures, the light-emitting element emits linearly polarized light in at least two polarization directions after being modulated by the at least two polarization structures, and the linearly polarized light is transmitted to the image receiver. The linearly polarized light in the at least two polarization directions is reflected by a target object and then enters the image receiver in sequence. In this way, the light-emitting elements can emit linearly polarized light in at least two different polarization directions, so that the number of the light-emitting elements can be reduced, and the structure in a three-dimensional imaging scheme is simplified. And the utilization rate of the light can be improved by utilizing the polarization structure of the light-emitting element.

Description

[0001] Cross-references to related applications

[0002] This application claims priority to Chinese Patent Application No. 202520064616.9, filed on January 10, 2025, entitled "Light Source, Image Receiver, Image Acquisition Device and Electronic Equipment", the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application relates to the field of biometric technology, and more specifically, to a light source, an image receiver, an image acquisition device, and an electronic device. Background Technology

[0004] With the development of portable terminal devices, the application of biometric technology is becoming increasingly widespread and in-depth. Taking electronic devices as an example, fingerprint recognition and facial recognition are increasingly used in device screen wake-up and identity authentication steps in various programs, improving device security and the flexibility of usage.

[0005] Currently, the main solutions for face recognition include binocular vision, time-of-flight, and structured light. Binocular vision's reconstruction accuracy is directly proportional to the camera baseline length, limiting its application. Time-of-flight cameras are relatively expensive and limited by temporal resolution, resulting in low 3D imaging accuracy. While structured light offers high imaging accuracy, its slow response time and low frame rate, coupled with decreasing accuracy over increasing imaging distance, have led to the gradual development of polarized 3D imaging technology for face recognition. However, current implementations of polarized 3D imaging are typically complex, with relatively low recognition accuracy, especially given the large overall size of the light source used. Utility Model Content

[0006] The purpose of this application is to address the shortcomings of the prior art by providing a light source, an image receiver, an image acquisition device, and an electronic device.

[0007] To achieve the above objectives, the technical solutions adopted in the embodiments of this application are as follows:

[0008] One aspect of this application provides a light source, including:

[0009] A light-emitting element having at least two polarization structures emits linearly polarized light in at least two polarization directions after being modulated by at least two polarization structures. The linearly polarized light in at least two polarization directions is reflected by the target object and then sequentially incident on an image receiver.

[0010] Optionally, for linearly polarized light with different polarization directions, the light-emitting element emits light in chronological order.

[0011] Optionally, at least a portion of the polarization structure is placed inside the light-emitting element and / or on the light-emitting surface.

[0012] Optionally, the light-emitting element includes at least two light-emitting units;

[0013] The light-emitting unit and the polarization structure have a one-to-one modulation relationship, or at least two of the light-emitting units share the same polarization structure.

[0014] Optionally, the polarization directions of any two polarization structures are different;

[0015] Alternatively; the light-emitting element has at least three polarization structures, at least two of which have different polarization directions, and some of which have the same polarization direction.

[0016] Optionally, the light-emitting element includes at least two light-emitting units, wherein when the light-emitting element is a laser device, the light-emitting unit is the optical resonant cavity of the laser device;

[0017] At least a portion of the polarization structure is placed inside the optical resonant cavity or on the light-emitting surface.

[0018] Optionally, the laser device includes at least two optical resonant cavities sharing the same substrate;

[0019] The optical resonator and the polarization structure have a one-to-one modulation relationship, or at least in some of the optical resonators, at least two optical resonators share the same polarization structure.

[0020] Optionally, at least two optical resonators share the same substrate, and there is an isolation region between adjacent optical resonators.

[0021] Optionally, the laser device includes a first electrode and at least two second electrodes, wherein the at least two optical resonators share the first electrode, and the at least two second electrodes are respectively configured to correspond one-to-one with the at least two optical resonators.

[0022] Optionally, the light source further includes an encapsulation structure for encapsulating the light-emitting element.

[0023] Optionally, the packaging structure has a diffuser located on the light-emitting side of the light-emitting element.

[0024] Optionally, in at least two polarization structures of the light-emitting element, the included angle between the polarization directions of at least two polarization structures is between 45° and 135°. For example, 45° ≤ included angle < 90°, and / or 90° < included angle ≤ 135°. More specifically, it can be 50°, 60°, 70°, 80°, 100°, 110°, or 120°, etc.

[0025] Optionally, in at least two polarization structures of the light-emitting element, the angle between the polarization directions of any two polarization structures is between 45° and 135°. For example, 45° ≤ angle < 90°, and / or 90° < angle ≤ 135°. More specifically, it can be 50°, 60°, 70°, 80°, 100°, 110°, or 120°, etc.

[0026] Optionally, the light-emitting element includes two polarization structures, the angle between the polarization directions of the two polarization structures being 45° to 135°. For example, 45° ≤ angle < 90°, and / or 90° < angle ≤ 135°. More specifically, it can be 50°, 60°, 70°, 80°, 100°, 110°, or 120°, etc.

[0027] Optionally, the light-emitting element includes two polarization structures, the polarization directions of the two polarization structures being perpendicular to each other.

[0028] Optionally, the polarization directions of the two polarization structures are the vertical direction and the horizontal direction, respectively.

[0029] Optionally, the light source further includes a packaging structure for encapsulating the light-emitting element, wherein the linearly polarized light is emitted through the light-emitting side surface of the packaging structure, and the peripheral contour of the light-emitting side surface has a plurality of straight edges, wherein the polarization direction of one of the polarization structures is parallel to at least one of the straight edges.

[0030] Optionally, the light-emitting element emits light in a wavelength band of 940 nm.

[0031] Another aspect of this application provides an image receiver, including an image sensor and a polarizer. The image sensor includes a photosensitive unit array, and the polarizer is disposed on the light-incident side of the photosensitive unit array. The polarization direction of the polarizer forms an angle less than or equal to the target angle with a polarization direction of the polarization structure of the light-emitting element. After being modulated by at least two polarization structures, the light-emitting element sequentially emits linearly polarized light in at least two polarization directions, and the linearly polarized light in at least two polarization directions is reflected by the target object and sequentially incident on the image receiver.

[0032] Optionally, the target angle is 5°, 10°, 15°, 20°, 25°, or 30°. For example, the included angle less than or equal to the target angle is 0° < included angle ≤ 5°, 0° < included angle ≤ 10°, 0° < included angle ≤ 15°, 0° < included angle ≤ 20°, 0° < included angle ≤ 25°, or 0° < included angle ≤ 30°.

[0033] Optionally, the polarization direction of the polarizer is the same as one of the polarization directions of the polarization structure of the light-emitting element.

[0034] Optionally, the image receiver further includes:

[0035] A lens group, located on the light-receiving side of the image sensor;

[0036] A filter unit is located between the lens group and the image sensor.

[0037] Optionally, the polarizing element is a polarizer, which is located on the side of the lens group away from the image sensor, and the filter unit and the polarizer are separate components.

[0038] Optionally, the polarizing element is a polarizer, which is located between the lens group and the image sensor.

[0039] Optionally, the polarizer is located between the filter unit and the image sensor.

[0040] Optionally, the filter unit and the polarizer are discrete components;

[0041] Alternatively, the filtering unit may be a filter, and the filter and the polarizer may share the same carrier plate and be formed on opposite sides of the carrier plate.

[0042] Optionally, the polarizer has a second micro / nano grating;

[0043] The peripheral edge of the polarizer is connected to the image sensor via a bridge structure to form a gap between the polarizer and the image sensor to accommodate the second micro-nano grating. Alternatively, the polarizer may also have a protective layer covering the second micro-nano grating, which is bonded to the image sensor via an adhesive layer.

[0044] Optionally, the polarizing element is a polarizing film, which is integrated into the image sensor.

[0045] Optionally, the polarizing element is a metal wire grid, which is integrated into the image sensor.

[0046] In another aspect of the embodiments of this application, an image acquisition device is provided, including a light-emitting device and a receiving device arranged along an optical path, wherein the light-emitting device is any of the above-mentioned light sources, and / or the receiving device is any of the above-mentioned image receivers.

[0047] In another aspect of this application, an electronic device is provided, including a device body and an image acquisition device as described above, wherein the image acquisition device is disposed on the device body.

[0048] In another aspect of the embodiments of this application, an electronic device is provided, including a device body and an image acquisition device. The image acquisition device includes a light-emitting device and a receiving device arranged along an optical path, wherein the light-emitting device is any of the above-mentioned light sources, and / or the receiving device is any of the above-mentioned image receivers.

[0049] The main body of the device includes a display screen, which includes a display module and a light-transmitting cover plate attached to the display side of the display module. The display module has a light channel extending from the display side to the non-display side. The light-emitting element and / or image sensor of the image acquisition device correspond to the opening of the light channel on the non-display side. The polarizing element of the image acquisition device is disposed on the light-transmitting cover plate and located at the opening of the light channel on the display side.

[0050] The beneficial effects of this application include:

[0051] This application provides a light source, an image receiver, an image acquisition device, and an electronic device, including a light-emitting element having at least two polarization structures. After modulation by these polarization structures, the light-emitting element emits linearly polarized light with at least two polarization directions. This linearly polarized light, after reflection from the target object, sequentially enters the image receiver. In other words, the light-emitting element itself can emit linearly polarized light with at least two different polarization directions, thus reducing the number of light-emitting elements and simplifying the structure of the 3D imaging scheme. Furthermore, the polarization structure of the light-emitting element can improve light utilization. Attached Figure Description

[0052] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0053] Figure 1 This is one of the structural schematic diagrams of an image acquisition device provided in an embodiment of this application;

[0054] Figure 2 One of the side cross-sectional views of a light-emitting element provided in an embodiment of this application;

[0055] Figure 3 A second side sectional view of a light-emitting element provided in an embodiment of this application;

[0056] Figure 4 A third side sectional view of a light-emitting element provided in an embodiment of this application;

[0057] Figure 5 Fourth side sectional view of a light-emitting element provided in an embodiment of this application;

[0058] Figure 6 One of the top views of a light-emitting element provided in an embodiment of this application;

[0059] Figure 7 A second top view of a light-emitting element provided in an embodiment of this application;

[0060] Figure 8 A top view of a light-emitting element provided in an embodiment of this application;

[0061] Figure 9 Fifth side sectional view of a light-emitting element provided in an embodiment of this application;

[0062] Figure 10 One of the side sectional views of an image receiver provided in an embodiment of this application;

[0063] Figure 11 A second side sectional view of an image receiver provided in an embodiment of this application;

[0064] Figure 12 A third side sectional view of an image receiver provided in an embodiment of this application;

[0065] Figure 13 A schematic diagram of an integrated structure of a polarizer and a filter provided in an embodiment of this application;

[0066] Figure 14 A top view of an electronic device provided in an embodiment of this application;

[0067] Figure 15 This is a side sectional view of an electronic device provided in an embodiment of this application.

[0068] Icons: 100 - Face; 200 - Light-emitting element; 210 - Optical resonant cavity; 221 - First electrode; 222 - Second electrode; 230 - Polarization structure; 240 - Barrier; 250 - Substrate; 260 - Base; 270 - Packaging frame; 280 - Diffuser; 300 - Image receiver; 310 - Image sensor; 320 - Polarizer; 321 - Second micro / nano grating; 330 - Lens group; 340 - Filter unit; 350 - Housing; 360 - Bridge structure; 370 - Protective layer; 380 - Carrier plate; 410 - Middle frame; 420 - Display screen; 421 - Display module; 422 - Light-transmitting cover plate; 423 - Light channel. Detailed Implementation

[0069] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0070] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. It should be noted that, unless otherwise specified, the various features in the embodiments of this application can be combined with each other, and the combined embodiments are still within the protection scope of this application.

[0071] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0072] In the description of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this application is in use. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. In addition, the terms "first," "second," and "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0073] Furthermore, terms such as "horizontal" and "vertical" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0074] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "set up," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0075] In the description of this application, the target object can be the face 100 in the accompanying drawings, or a part of the face 100 (such as cheeks, nose, and eyes). Of course, it is not limited to this, and can also be other objects with three-dimensional dimensions, such as fingers, palms, etc.

[0076] One aspect of this application provides a light source, which will be described below.

[0077] like Figure 1 As shown, the light source includes a light-emitting element 200. Specifically, the light source may include any number of light-emitting elements 200, such as one, two, three, etc.

[0078] A single light-emitting element 200 can be an integrated structure, thus the light-emitting element 200 itself has a high degree of integration, which can meet a variety of application scenarios, especially application scenarios in small spaces, such as wearable devices, mobile terminals and other electronic devices.

[0079] The light-emitting element 200 can be a bare die structure, which allows for higher integration with other electronic devices according to its application scenarios and requirements, helping to reduce size and improve electrical performance. Of course, the light-emitting element 200 can also be a packaged device with a package structure, in which case the light-emitting element 200 itself has better stability and reliability.

[0080] The light source can be used for polarization three-dimensional imaging. Specifically, the light-emitting element 200 can be used for polarization three-dimensional imaging. Therefore, the light-emitting element 200 emits linearly polarized light with at least two different polarization directions.

[0081] To facilitate understanding, we will first introduce an overview of the principle by which the image receiver 300 applies the light-emitting element 200 to polarization-based three-dimensional imaging: Please continue reading... Figure 1In 3D imaging, linearly polarized light with different polarization directions emitted by the light-emitting element 200 is sequentially transmitted to the surface of the target object in chronological order. After reflection from the target object, each polarization direction of the linearly polarized light carries polarization information corresponding to the contour surface of the target object. These polarized lights are then sequentially incident on the image receiver 300 in the same chronological order. The image receiver 300 can then generate multiple polarization images according to the incident order. Based on these multiple polarization images, the contour surface of the target object can be reconstructed more accurately, facilitating high-precision target object recognition. Furthermore, polarization-based 3D imaging can be achieved through the light source and image receiver 300, resulting in a relatively simple structure. In particular, since the light-emitting element 200 itself can emit linearly polarized light with at least two different polarization directions, the number of light-emitting elements 200 can be reduced. For example, only one light-emitting element 200 can be used for applications such as 3D imaging, target object recognition, and anti-counterfeiting identification.

[0082] To further understand, linearly polarized light has the following characteristics: when linearly polarized light travels to the surface of a target object and is reflected by the target object, the polarization state of each ray in the linearly polarized light changes. The amount of change in the polarization state of each ray is related to the material of the target object's surface where the ray is incident and the incident angle (spatial position) of each point on the target object's contour surface. Return to... Figure 1 The light-emitting element 200 emits linearly polarized light toward the face 100 (target object). Utilizing the aforementioned characteristics of linearly polarized light, and based on the spatial differences in the points within the contour surface of the face 100 (the incident angle of linearly polarized light differs at different points) and the surface material of the face 100, the linearly polarized light reflected by the face 100 carries polarization information corresponding to the face contour surface. Subsequently, it is received sequentially by the image receiver 300 according to the incident order. Thus, the image receiver 300 sequentially generates multiple polarized images based on their incident order. Since the polarization directions of each linearly polarized light are different, by analyzing the differences between multiple polarized images, information about the face 100 in the depth direction can be obtained. Based on this, the contour surface of the face 100 can be reconstructed more accurately, which helps to achieve higher-precision face recognition.

[0083] It should be understood that polarized images can be used for face recognition, including face matching and / or anti-spoofing detection. Face matching refers to verifying whether the face to be verified is the same person as a pre-recorded correct face in the database (generally determined by calculating similarity). The correct face is also called a face template or database image. Anti-spoofing detection refers to verifying whether the face to be verified is a real face or a forgery such as a photo, video, or silicone face mold. Of course, when the target object is changed to a hand, gesture imaging, vein and palm print imaging, etc., can also be performed.

[0084] As mentioned above, the light-emitting element 200 itself can emit linearly polarized light with at least two polarization directions. For this purpose, the light-emitting element 200 will be further described below.

[0085] The light-emitting element 200 integrates a polarization structure 230. For example, the light-emitting element 200 has a built-in polarization structure 230. Here, "built-in" means that the polarization structure 230 is part of the light-emitting element 200. In this way, the light emitted from the light-emitting element 200 is all linearly polarized light.

[0086] Of course, the light-emitting element 200 with polarization structure 230 can still maintain an integrated structure.

[0087] Since the light-emitting element 200 needs to emit linearly polarized light with at least two different polarization directions, the light-emitting element 200 has at least two polarization structures 230. That is, the light generated inside the light-emitting element 200 is first modulated by at least two polarization structures 230 when it is emitted, and then finally emitted from the light-emitting element 200 as linearly polarized light with at least two polarization directions.

[0088] It's important to understand that the number of polarization structures 230 can be greater than or equal to the number of linearly polarized lights with different polarization directions. Specifically: based on the principle of polarization, the light generated inside the light-emitting element 200, after being modulated by the polarization structure 230, can ultimately form linearly polarized light. Therefore, the polarization direction of the linearly polarized light depends on the polarization structure 230. Thus, firstly, the corresponding polarization structure 230 can be set according to the required polarization direction. Secondly, when the number of polarization structures 230 is equal to the number of linearly polarized lights with different polarization directions, it means that the polarization directions of the linearly polarized light modulated by any two polarization structures 230 are not the same. Conversely, when the number of polarization structures 230 is greater than the number of linearly polarized lights with different polarization directions, it means that there are some cases where the linearly polarized light modulated by some polarization structures 230 has the same polarization direction. This increases the number of linearly polarized lights with the same polarization direction, thereby giving them a stronger light intensity.

[0089] Therefore, in some possible implementations, any two linearly polarized lights emitted by the light-emitting element 200 may have different polarization directions.

[0090] In some other possible implementations, among all the linearly polarized light emitted by the light-emitting element 200, there may be at least two linearly polarized lights with different polarization directions, and there may also be at least two linearly polarized lights with the same polarization direction.

[0091] When linearly polarized light with different polarization directions is emitted from the light-emitting element 200, it can be emitted sequentially in time. In other words, any two linearly polarized lights with different polarization directions will be emitted from the light-emitting element 200 at different times.

[0092] When linearly polarized light with the same polarization direction is emitted from the light-emitting element 200, they can be emitted at the same time. In other words, the linearly polarized light with the same polarization direction is emitted from the light-emitting element 200 at the same time, which can help increase the intensity of light with the same polarization direction.

[0093] In some possible implementations, when the number of polarization structures is appropriate, such as more than three, the light generated inside the light-emitting element can also be modulated by at least two polarization structures in sequence to form the desired linearly polarized light.

[0094] In different implementations, the light-emitting element 200 can be an LED lamp, a laser device, etc. When the light-emitting element 200 is an LED lamp, it includes a PN junction for generating photons; in other words, the light inside the light-emitting element 200 is generated from the PN junction. When the light-emitting element 200 is a laser device, the laser device includes an optical resonant cavity 210. The optical resonant cavity 210 serves as the light-emitting unit of the light-emitting element 200. Under electrical excitation, the optical resonant cavity 210 is used to repeatedly reflect photons, thereby exciting more atomic transitions and releasing more photons of the same frequency and phase. In other words, the light inside the light-emitting element 200 is generated from the optical resonant cavity 210 and ultimately exits from one side of the optical resonant cavity 210. Of course, the laser device can include any number of optical resonant cavities 210. For example, the laser device includes at least two optical resonant cavities 210; more specifically, the number can be two, three, four, etc.

[0095] As mentioned above, at least two polarization structures 230 are part of the light-emitting element 200. When specifying the exact location of the polarization structure 230 within the light-emitting element 200, several possibilities exist:

[0096] Scenario 1: All polarization structures 230 included in the light-emitting element 200 are located inside the light-emitting element 200 or on its light-emitting surface. For example, when the light-emitting element 200 is a laser device, such as... Figure 2 As shown, all polarization structures 230 included in the laser device are located on the light-emitting surface of the light-emitting element 200 (i.e., above the light-emitting surface of the optical resonant cavity 210, and the polarization structures 230 can be closely attached to the light-emitting surface of the optical resonant cavity 210). For example, when the light-emitting element 200 is a laser device, such as... Figure 3 As shown, all polarization structures 230 included in the laser device are located inside the optical resonant cavity 210. Similarly, when the light-emitting element 200 is an LED, all polarization structures 230 included in the LED are located on the surface of the PN junction.

[0097] Scenario 2: Among all the polarization structures 230 included in the light-emitting element 200, some polarization structures 230 are located inside the light-emitting element 200 or on its light-emitting surface. For example, when the light-emitting element 200 is a laser device, some of the polarization structures 230 included in the laser device are located on the light-emitting surface of the light-emitting element 200. Another example is that when the light-emitting element 200 is a laser device, some of the polarization structures 230 included in the laser device are located inside the optical resonant cavity 210. Yet another example is that when the light-emitting element 200 is an LED lamp, some of the polarization structures 230 included in the LED lamp are located on the surface of the PN junction.

[0098] Scenario 3: Of all the polarization structures 230 included in the light-emitting element 200, a portion of the polarization structures 230 are located inside the light-emitting element 200, while another portion of the polarization structures 230 are located on the light-emitting surface of the light-emitting element 200. For example, when the light-emitting element 200 is a laser device, such as... Figure 4 As shown, a portion of the polarization structure 230 of the laser device is located inside the optical resonant cavity 210, while another portion of the polarization structure 230 is placed on the light-emitting surface of the light-emitting element 200.

[0099] It should be understood that the light-emitting surface of the light-emitting element 200 refers to the critical surface where light generated inside the light-emitting element 200 leaves the light-emitting element 200. For example, when the light-emitting element 200 is a laser device, the laser device includes an optical resonant cavity 210. Since the light inside the light-emitting element 200 is generated in the optical resonant cavity 210, one side surface of the optical resonant cavity 210 (such as...) can be emitted. Figure 3 ) or above one side surface (e.g. Figure 2 The position of the polarization structure 230 serves as the light-emitting surface of the light-emitting element 200.

[0100] Furthermore, the polarization structure 230 can be a micro / nano grating, i.e., a grating of micro / nano size (which can be a wire grating structure), thus having a smaller size. At the same time, it also facilitates its better integration into the fabrication process of the light-emitting element 200. For example, when fabricating the light-emitting element 200 using semiconductor processes, the process steps for fabricating the micro / nano grating can be increased.

[0101] In summary, placing the polarization structure 230 on the light-emitting surface or inside the light-emitting element 200 can significantly increase the proportion of light generated inside the light-emitting element 200 that is modulated by the polarization structure 230, thereby improving light utilization. In particular, when the polarization structure 230 is placed inside the optical resonant cavity 210 or on the light-emitting surface of the light-emitting element 200, the photons generated inside the optical resonant cavity 210 are all modulated into the expected linearly polarized light by the polarization structure 230 when they finally leave the laser device. The light-emitting element 200 will not generate stray light, allowing the light utilization rate to approach or even reach 100%.

[0102] Further explanation regarding the light-emitting element 200: In order for the light-emitting element 200 to emit at least two linearly polarized light with different polarization directions, the light-emitting element 200 can include at least two light-emitting units that are integrally set (i.e., at least two light-emitting units share the same substrate) or separate. Each light-emitting unit can generate photons on its own. The photons generated by each light-emitting unit are finally modulated by the polarization structure 230 to form a linearly polarized light. In other words, the number of linearly polarized light emitted from the light-emitting element 200 corresponds one-to-one with the number of light-emitting units.

[0103] For example, when the light-emitting element 200 is a laser device, the light-emitting unit of the light-emitting element 200 can be the optical resonant cavity 210 of the laser device. When the light-emitting element 200 is an LED lamp, the light-emitting unit of the light-emitting element 200 can be the PN junction of the LED lamp.

[0104] Since the light-emitting element 200 includes at least two light-emitting units and at least two polarization structures 230, it is necessary to explain the correspondence between the light-emitting units and the polarization structures 230:

[0105] Scenario 1: The number of light-emitting units and polarization structures 230 are equal, and they have a one-to-one modulation relationship. That is, the photons generated inside a light-emitting unit can ultimately be modulated by its corresponding polarization structure 230 to form linearly polarized light. For example... Figure 2 As shown, when the light-emitting element 200 is a laser device, Figure 2 The diagram illustrates two optical resonators 210 of a laser device, and correspondingly, two polarization structures 230. The two optical resonators 210 and the two polarization structures 230 are in a one-to-one correspondence. Each optical resonator 210 has a corresponding polarization structure 230 on its output surface. Thus, photons generated by the left optical resonator 210 are ultimately modulated by the polarization structure 230 on its output surface and emitted as linearly polarized light. Photons generated by the right optical resonator 210 are also ultimately modulated by the polarization structure 230 on its output surface and emitted as another linearly polarized light. When the laser device includes more than two optical resonators 210, the configuration can be based on two optical resonators 210. Similarly, when the position of the polarization structure 230 changes from the output surface to inside the optical resonator 210, the configuration can still be based on two optical resonators 210, the only difference being the position of the polarization structure 230.

[0106] For example Figure 6 From a top-down viewpoint, four optical resonant cavities 210 and four polarization structures 230 are shown. The four optical resonant cavities 210 are integrally formed, and each optical resonant cavity 210 has a polarization structure 230 on its surface, so that the number of optical resonant cavities 210 and polarization structures 230 are equal, and the two have a one-to-one modulation relationship.

[0107] Scenario 2: The number of light-emitting units is greater than the number of polarization structures 230. Therefore, there are at least two light-emitting units sharing the same polarization structure 230. Consequently, the linearly polarized light emitted by the light-emitting units sharing the polarization structure 230 has the same polarization direction. Specifically, each light-emitting unit will share the same polarization structure 230 with at least one other light-emitting unit, for example... Figure 7 As shown in the diagram, from a top-down view, four optical resonators 210 and two polarization structures 230 are displayed. The four optical resonators 210 are integrally formed (i.e., multiple optical resonators 210 share the same substrate). The surfaces of the two uppermost optical resonators 210 are provided with the same polarization structure 230. Therefore, the two uppermost optical resonators 210 ultimately form two linearly polarized lights with the same polarization direction through their corresponding polarization structure 230. The surfaces of the two lowermost optical resonators 210 are also provided with the same polarization structure 230. Therefore, the two lowermost optical resonators 210 ultimately form two linearly polarized lights with the same polarization direction through their corresponding polarization structure 230. Figure 7 The examples shown only show that the number of light-emitting units sharing the same polarization structure 230 is equal, and in each case there are two. In other examples, the number of light-emitting units sharing the same polarization structure 230 can also be three, four, five, etc. Furthermore, the number of light-emitting units sharing the same polarization structure 230 can be equal or unequal.

[0108] Scenario 3: Similar to Scenario 2, the number of light-emitting units is greater than the number of polarization structures 230. Therefore, there are at least two light-emitting units sharing the same polarization structure 230. Consequently, the linearly polarized light emitted by light-emitting units sharing the polarization structure 230 has the same polarization direction. Specifically, the difference lies in that some light-emitting units share the same polarization structure 230 with at least one other light-emitting unit, while other light-emitting units have their own separate polarization structure 230. For example... Figure 8 As shown in the diagram, from a top-down view, four optical resonant cavities 210 and three polarization structures 230 are displayed. The four optical resonant cavities 210 are integrally formed. The surfaces of the two uppermost optical resonant cavities 210 each have a polarization structure 230, while the surfaces of the two lowermost optical resonant cavities 210 have the same polarization structure 230. Therefore, the two lowermost optical resonant cavities 210 ultimately form two linearly polarized lights with the same polarization direction through their corresponding same polarization structure 230. Of course... Figure 7 The number of light-emitting units sharing the same polarization structure 230 shown can be arbitrarily varied, such as three, four, five, etc. The number of light-emitting units each occupying a polarization structure 230 can also be arbitrarily varied, such as three, four, five, etc.

[0109] As described above, the light-emitting element 200 needs to emit linearly polarized light with at least two different polarization directions, and the polarization direction of the linearly polarized light depends on the polarization structure 230 that modulates the linearly polarized light. Therefore, initially, there is no limitation on the number of polarization structures 230 included in the light-emitting element 200, such as at least two (two, three, four, five, etc.). Next, when the number of polarization structures 230 in the light-emitting element 200 is at least two, at least two polarization structures 230 have different polarization directions, while the polarization directions of the remaining polarization structures 230 can be reasonably chosen to be the same. In other words, any two polarization structures 230 have different polarization directions; or; the light-emitting element 200 has at least three polarization structures 230, at least two of which have different polarization directions, and some of the polarization structures 230 have the same polarization direction.

[0110] For example: when there are two polarization structures 230 in the light-emitting element 200, the two polarization structures 230 have different polarization directions. When there are three polarization structures 230 in the light-emitting element 200, the three polarization structures 230 have different polarization directions. When there are three polarization structures 230 in the light-emitting element 200, two of the polarization structures 230 have the same polarization direction, and both have a different polarization direction from the third polarization structure 230. When the number of polarization structures 230 in the light-emitting element 200 exceeds three, the number of polarization structures 230 with the same polarization direction and the number of polarization structures 230 with different polarization directions can be freely and reasonably allocated according to requirements.

[0111] In some possible implementations, all light-emitting units in the light-emitting element 200 share the same substrate (also called the base plate) so that they can be integrally formed. For example, in mass production, a large number of light-emitting units can be fabricated on the same substrate. In traditional processes, it is necessary to first cut individual light-emitting units to form separate light-emitting units. However, in this application, all light-emitting units of the same light-emitting element 200 can be cut directly. In this way, the different light-emitting elements 200 after cutting can be separated from each other, but all light-emitting units in the same light-emitting element 200 are not separated from each other and still share the substrate. Thus, the gaps between all light-emitting units in the light-emitting element 200 of this application are very small or almost non-existent. This allows the light-emitting element 200 to emit multiple linearly polarized lights while further miniaturizing the overall volume. Especially when applied to under-display hole-punch scenarios, it can further reduce the hole diameter and further increase the screen-to-body ratio.

[0112] In some possible implementations, such as Figure 5As shown, the laser device includes at least two optical resonant cavities 210 sharing the same substrate 250, and more specifically, the number may be two, three, four, five, etc.

[0113] In some possible implementations, such as Figure 5 As shown, the laser device also includes a base 260, which is located on the side surface of the substrate 250 opposite to the optical resonant cavity 210.

[0114] In some possible implementations, the base 260 may be a packaging substrate that can be used to connect to the electrodes of the light-emitting element 200.

[0115] In some possible implementations, to prevent potential interference between adjacent optical resonant cavities 210, an isolation region can be provided between them. In different examples, the isolation region can be formed by an ion implantation region or by a barrier wall 240 structure. For example... Figures 2 to 7 In this configuration, a baffle 240 is provided between adjacent optical resonant cavities 210. The baffle 240 serves as an isolation zone to separate different optical resonant cavities 210.

[0116] In some possible implementations, when the light-emitting element 200 is a laser device, the light-emitting surfaces of its at least two optical resonant cavities 210 may be identical, thus making the intensity of each linearly polarized light more uniform. Of course, other implementations may differ.

[0117] In some possible implementations, when the light-emitting element 200 is a laser device, the laser device may be a vertical cavity surface emitting laser (VCSEL), including but not limited to top-emitting and bottom-emitting types.

[0118] In some possible implementations, a vertical cavity surface-emitting laser may include an active region, distributed Bragg mirrors (DBRs) distributed on the upper and lower sides of the active region, a cathode electrode, and an anode electrode. The active region includes a multi-quantum-well region. The active region can work with the distributed Bragg mirrors on the upper and lower sides to form the aforementioned optical resonant cavity 210. The cathode electrode and anode electrode are located on the distributed Bragg mirrors on the upper and lower sides.

[0119] In some possible implementations, the laser device includes a first electrode 221 and at least two second electrodes 222, wherein at least two optical resonant cavities 210 share the first electrode 221, and at least two second electrodes 222 are respectively disposed in a one-to-one correspondence with at least two optical resonant cavities 210. For example... Figures 2 to 7As shown, a common first electrode 221 is provided on the bottom surface of the two optical resonant cavities 210, and a separate second electrode 222 is provided on the top surface of each optical resonant cavity 210. Thus, when selectively controlling the emission of light from the optical resonant cavities 210, the second electrode 222 and the first electrode 221 corresponding to the optical resonant cavity 210 that needs to emit light can be energized sequentially. When controlling the optical resonant cavities 210 to emit light in a time sequence, the second electrode 222 corresponding to the optical resonant cavity 210 that needs to emit light can be energized sequentially, while the common first electrode 221 can be continuously energized during laser operation.

[0120] Of course, in different implementations, the first electrode 221 can be a cathode and the second electrode 222 can be an anode; or, the first electrode 221 can be an anode and the second electrode 222 can be a cathode.

[0121] Of course, for optical resonators 210 that are expected to emit linearly polarized light with the same polarization direction, their energizing time points can be the same. However, for optical resonators 210 that are expected to emit linearly polarized light with different polarization directions, their energizing periods are staggered. This will prevent the following situation: linearly polarized light with different polarization directions will be received by the image sensor (more specifically, the photosensitive unit array) at the same time, thus avoiding interference.

[0122] In some possible implementations, the light source also includes a packaging structure for encapsulating the light-emitting element 200. Specifically, when the light-emitting element 200 is a packaged device with a packaging structure, the packaging structure includes a base 260 and a packaging frame 270, which cooperate to form a packaging cavity in which the light-emitting element 200 is housed.

[0123] In some possible implementations, such as Figure 9 As shown, the packaging structure also includes a diffuser 280. The diffuser 280, the base 260, and the packaging frame 270 cooperate to form a packaging chamber, in which the light-emitting unit is built-in. The diffuser 280 is located on the light-emitting side of the light-emitting unit, which allows the linearly polarized light (small emission angle) emitted from the polarization structure 230 to be diffused (expanded) by the diffuser 280. The number of diffusers 280 can be one or at least two. At least two separate diffusers 280 correspond to at least two polarization structures respectively. More specifically, it can be a one-to-one relationship between diffuser and polarization structure, or one diffuser corresponding to multiple polarization structures, or one polarization structure corresponding to multiple diffusers.

[0124] In some possible implementations, the packaging structure can be a ceramic package, such as... Figure 9 As shown, the encapsulation frame 270 is a ceramic structure.

[0125] In some possible implementations, the light source has at least two emitting surfaces, which may be interconnected and / or separated from each other, emitting linearly polarized light with at least two polarization directions through the at least two emitting surfaces. The emitting surfaces may be circular or rectangular in shape. The encapsulation structure may have an identifier to indicate one polarization direction of the polarization structure.

[0126] In some possible implementations, the light source has at least two emitting regions, which may be interconnected and / or separated from each other, emitting linearly polarized light in at least two polarization directions through each of the at least two emitting regions. The emitting regions may be circular or rectangular in shape. The encapsulation structure may have an identifier to indicate one polarization direction of the polarization structure.

[0127] The light-emitting element described above is capable of emitting linearly polarized light with at least two different polarization directions, and therefore has at least two polarization structures 230. Consequently, in some possible embodiments, among all the polarization structures within a single light-emitting element, at least two polarization structures have polarization directions that form an angle, and this angle ranges from 45° to 135°, for example, 45° ≤ angle < 90°, and / or 90° < angle ≤ 135°. More specifically, the angle can also be 50°, 60°, 70°, 80°, 100°, 110°, or 120° within the aforementioned range. Of course, in some other possible implementations, in all polarization structures within a single light-emitting element, there is an angle between the polarization directions of any two polarization structures, the angle being in the range of 45° to 135°, for example, 45° ≤ angle < 90°, and / or 90° < angle ≤ 135°. More specifically, the angle can also be 50°, 60°, 70°, 80°, 100°, 110°, or 120°, etc.

[0128] Under certain considerations, such as device miniaturization, low cost, and yield, it may be necessary to minimize the number of polarization structures within the light-emitting element. For example, in some possible implementations, the light-emitting element includes two polarization structures, and the included angle between the polarization directions of these two polarization structures is in the range of 45° to 135°, such as 45° ≤ included angle < 90°, and / or 90° < included angle ≤ 135°. More specifically, the included angle can be 50°, 60°, 70°, 80°, 100°, 110°, or 120°, etc.

[0129] It should be understood that when the angle between the polarization directions of the two polarization structures is between 45° and 135°, the linearly polarized light modulated by each of them will have obvious differences (the polarization information carried by the linearly polarized light corresponding to the facial contour surface will have obvious differences). This can achieve better results in realizing functions such as three-dimensional imaging, target object recognition, and anti-counterfeiting recognition.

[0130] In some possible implementations, within the aforementioned angle range, the polarization directions of the two polarization structures 230 included in the light-emitting element 200 can be perpendicular to each other, so that the light-emitting element 200 can emit linearly polarized light with mutually perpendicular polarization directions.

[0131] In some possible implementations, the light-emitting element 200 includes two light-emitting units and two polarization structures 230, which helps simplify the structure of the light source and facilitates its miniaturization. Simultaneously, the image receiver 300 also forms two polarized images, which can reduce the data processing load of the image receiver 300. In some possible implementations, the polarization directions of the two polarization structures 230 are perpendicular to each other, so that the light-emitting element 200 can emit two linearly polarized lights with mutually perpendicular polarization directions.

[0132] In some possible implementations, the polarization directions of the two polarization structures 230 are vertical and horizontal, respectively.

[0133] For example, if vertical polarization is defined as 0 degrees, then horizontal polarization is 90 degrees. This maximizes the difference between the two linearly polarized lights emitted by the light-emitting element 200, resulting in the greatest information difference between the two polarized images obtained by the image sensor 310, which is beneficial for target identification.

[0134] In some possible implementations, when the light source further includes a packaging structure for encapsulating the light-emitting element, linearly polarized light emitted from the light-emitting element can exit through the light-emitting side surface of the packaging structure. The light-emitting side surface of the packaging structure has a peripheral contour with several straight edges, and the polarization direction of one of the polarization structures is parallel to at least one of these straight edges. For example, when the peripheral contour is a triangle, square, or rectangle, the polarization direction of one of the polarization structures is parallel to one of the straight edges of the triangle, square, or rectangle. If the light-emitting element includes two polarization structures, and the polarization directions of the two polarization structures are perpendicular to each other, the polarization direction of one of the polarization structures is parallel to at least one of the straight edges of the aforementioned peripheral contour.

[0135] In some possible implementations, the light-emitting element 200 emits light in the infrared band, such as 940nm, which can reduce the sensitivity of the human eye.

[0136] In some possible implementations, the degree of polarization of the linearly polarized light emitted by the light-emitting element 200 should meet a threshold requirement, such as not being equal to zero, to improve the usability of the linearly polarized light. The degree of polarization can be represented by P, and P = (I max -I min ) / (I max +I min), I max I represents the luminous intensity of linearly polarized light in the direction of maximum polarization. min denoted as , where is the luminous intensity of linearly polarized light in the direction of minimum polarization.

[0137] This application provides an image receiver 300, which includes a polarizer and an image sensor 310. The image sensor 310 includes a photosensitive unit array, and the polarizer is located on the light-incident side of the photosensitive unit array. When the polarizer is a polarizing film or a metal wire grid, the polarizing film or metal wire grid can be integrated inside the image sensor 310. When the polarizer is a polarizing plate, it can be disposed on the surface of the image sensor or disposed separately from it. These will be described separately below.

[0138] In another aspect of this application, an image receiver 300 is provided, which will be described below. The polarizing element can be a polarizing film.

[0139] Please refer to Figure 1 The image receiver 300 will be described below:

[0140] The image receiver 300 includes a polarizer 320 and an image sensor 310. The image sensor 310 is located on the light-emitting side of the polarizer 320, meaning that linearly polarized light is reflected by the target object, passes through the polarizer 320, and then enters the image sensor 310. Furthermore, the polarization direction of the polarizer 320 has the following relationship with the light source: the polarization direction of the polarizer forms an angle less than or equal to the target angle with one of the polarization directions of the light-emitting element's polarization structure. Specifically, if the light source includes a light-emitting element with at least two polarization structures, then among all the polarization directions of the polarization structure within the same light-emitting element, there exists a polarization direction that forms an angle less than or equal to the target angle with the polarization direction of the polarizer. This light source can be any of the aforementioned light sources or a different light source. When it is not any of the aforementioned light sources, it should satisfy the following condition: after being modulated by at least two of the aforementioned polarization structures, the light-emitting element sequentially emits linearly polarized light with at least two polarization directions, and the linearly polarized light with at least two polarization directions is reflected by the target object and then sequentially enters the image receiver.

[0141] For example, in some possible implementations, when all polarization structures of the light-emitting element have at least two polarization directions, the polarizer (which may specifically be a polarizer, polarizing film, or metal grid) has an angle with one of the polarization directions that is less than or equal to the target angle, and the polarizer also has an angle with the other polarization directions that is greater than the target angle. This allows the image receiver to receive more information from some linearly polarized light and less information from other linearly polarized light, thereby creating the expected differentiation of information from different linearly polarized light.

[0142] In some possible implementations, the aforementioned target angle is 5°, 10°, 15°, 20°, 25°, or 30°. For example, the included angle less than or equal to the target angle satisfies the following conditions: 0° < included angle ≤ 5°, 0° < included angle ≤ 10°, 0° < included angle ≤ 15°, 0° < included angle ≤ 20°, 0° < included angle ≤ 25°, or 0° < included angle ≤ 30°.

[0143] In some possible implementations, the polarization direction of the polarizer is the same as one of the polarization directions of the light-emitting element's polarization structure, in which case the included angle is 0°.

[0144] For example Figure 1 The image shows a light source including a light-emitting element 200, which has two polarization structures 230. The polarization direction of the polarizer 320 is the same as that of one of the polarization structures 230, and perpendicular to the polarization direction of the other polarization structure 230.

[0145] In some possible implementations, such as Figures 10 to 12 The image receiver 300 also includes a lens group 330, which is located on the light receiving side of the image sensor 310. The lens group 330 can guide the linearly polarized light incident on the image sensor 310 so that the polarized image formed by the image sensor 310 is clearer. The lens group 330 includes several lenses, including but not limited to concave lenses, convex lenses, irregularly shaped lenses, etc.

[0146] In some possible implementations, such as Figures 10 to 12 The image receiver 300 also includes a filter unit 340, which can match the emission band of the light-emitting element 200 to filter out as much interference light (such as ambient light, sunlight, etc.) outside the emission band as possible.

[0147] In some possible implementations, such as Figures 10 to 12 The filter unit 340 is located between the lens group 330 and the image sensor 310, which helps to improve the quality of the polarized image formed by the image sensor 310. Of course, in other embodiments, the filter unit 340 may also be located above the lens group 330 or between several lenses.

[0148] It should be understood that the filter unit 340 can be a filter or a filter film. Specifically, when it is a filter film, depending on its location, the filter film can be integrated inside the image sensor 310, coated on the surface of the image sensor 310, or coated on the surface of the lens. When the filter unit 340 is a filter, the filter generally has a carrier plate 380 (such as a glass carrier plate 380) and can be set independently of the image sensor 310.

[0149] In some possible implementations, such as Figures 10 to 12The image receiver 300 also includes a lens barrel that can accommodate the lens group 330.

[0150] The following are some examples of possible positions for the polarizer 320 and the filter unit 340:

[0151] Example 1

[0152] Please refer to Figure 10 The polarizer 320 is located on the side of the lens group 330 facing away from the image sensor 310, and the filter unit 340 is located between the lens group 330 and the image sensor 310. Therefore, linearly polarized light is first modulated by the polarizer 320, then guided by the lens group 330 and incident on the filter unit 340, and finally incident on the image sensor 310 after being filtered. In this example, the polarizer 320 has a second micro-nano grating 321, which should be located on the surface of the polarizer 320 near the lens group 330 to provide protection. The polarizer 320 should have a certain gap with the lens group 330 to prevent the lens group 330 from damaging the second micro-nano grating 321 on the surface of the polarizer 320. More specifically, the polarizer 320 can be located inside the lens barrel or attached to the top of the lens barrel.

[0153] In this example, the filter unit 340 and the polarizer 320 should be discrete components, that is, the filter unit 340 and the polarizer 320 are two independent elements.

[0154] Example 2

[0155] Please refer to Figure 11 or Figure 12 The polarizer 320 is located between the filter unit 340 and the image sensor 310. This allows linearly polarized light to be filtered first by the filter unit 340, improving the signal-to-noise ratio, and then polarized by the polarizer 320, which helps improve the quality of the polarized image. In other words, stray light outside the emission wavelength band can be filtered out first by the filter unit 340, and then polarized by the polarizer 320, resulting in purer light that is beneficial for recognition.

[0156] In this example, the filter unit 340 and the polarizer 320 can be discrete components or integrated components, specifically:

[0157] Figure 11 or Figure 12 As shown, the filter unit 340 and the polarizer 320 are two independent components. The filter unit 340 is positioned closer to the lens group 330, while the polarizer 320 is positioned closer to the image sensor 310. The polarizer 320 and the image sensor 310 can be connected using a bridging or surface-mount method, for example... Figure 11As shown, the polarizer 320 and the image sensor 310 are connected via a bridge structure 360. Specifically, the bridge structure 360 ​​can be a support column or a support ring, etc. The periphery of the polarizer 320 is connected to the image sensor 310 via the bridge structure 360. This allows for a certain gap between the polarizer 320 and the image sensor 310, which can accommodate the second micro / nano grating 321 on the polarizer 320, preventing it from contacting the surface of the image sensor 310 and causing damage. For example... Figure 12 As shown, the polarizer 320 and the image sensor 310 can be connected by surface bonding. Specifically, the polarizer 320 also has a protective layer 370 covering the second micro-nano grating 321. In this way, the protective layer 370 (which can be a silicon dioxide layer) can protect the second micro-nano grating 321. Then, the protective layer 370 is bonded to the image sensor 310 through an adhesive layer.

[0158] Of course, such as Figure 13 As shown, the filter unit 340 and polarizer 320 can also be integrated components, that is, the filter unit 340 is a filter, and the filter and polarizer 320 share the same carrier plate 380. They no longer require separate carriers; the polarizer 320 is directly formed on one surface of the carrier plate 380, and the filter is directly formed on the other surface of the carrier plate 380. In this case, the integrated component and the image sensor 310 can still be connected by bridging or surface mounting, and the specific configuration can be reasonably set according to the methods described above.

[0159] Example 3

[0160] The filter unit 340 is located between the polarizer 320 and the image sensor 310 (in other words, the polarizer 320 is located between the lens group 330 and the filter unit 340), so that the linearly polarized light first passes through the polarizer 320 and then is filtered by the filter unit 340.

[0161] In this example, the filter unit 340 and the polarizer 320 can also be discrete components or integrated components. The difference from Example 2 is that the positions of the filter unit 340 and the polarizer 320 are different.

[0162] In some possible implementations, such as Figures 10 to 12The image receiver 300 also includes a housing 350, which has a light inlet that connects to the lens barrel. The image sensor 310 is located inside the housing 350. To facilitate the smooth incidence of linearly polarized light onto the image sensor 310, the end of the light inlet corresponds to the image sensor 310. A lens group 330 is located inside the lens barrel, and a filter unit 340 is located between the lens group 330 and the image sensor 310. This filter unit can be located either inside the lens barrel or inside the housing 350. The housing 350 and the lens barrel not only protect the optical components contained in the image receiver 300 but also support each optical component, ensuring it is positioned appropriately.

[0163] In some possible implementations, the bandpass of the filter unit 340 should include the emission band of the light source (i.e., the light-emitting element 200). For example, when the light-emitting element 200 is an infrared light source and its emission band is 940nm, the filter unit 340 can be a narrowband pass filter unit 340 with a bandpass band of 940nm±10nm. By using the two together, interference stray light generated by sunlight can be effectively filtered out.

[0164] In another aspect of this application, an image receiver 300 is provided, which will be described below. The difference from the aforementioned image receiver 300 is that the polarizing element is a polarizing film or a metal wire grid (of course, in other embodiments, the polarizing film can also be presented as a metal wire grid). The polarizing film or metal wire grid can also be built into the image sensor 310. In this case, the polarizing film or metal wire grid may not have a carrier (such as glass), but is simply a film layer or wire grid structure. The remaining configurations of the polarizing element can be the same or similar as described above, provided they do not conflict. Similarly, the configurations of the lens group 330 and the filter can be understood with reference to the foregoing description.

[0165] In some possible examples, the image sensor 310 may include a photosensitive unit array, which may be formed by a two-dimensional array of multiple photosensitive units, with the light-receiving surfaces of the multiple photosensitive units on the same side combined to form the photosensitive surface of the photosensitive unit array.

[0166] In image acquisition devices, the polarizing film can be configured in several ways, including but not limited to the following (the same applies to metal wire grids):

[0167] Form 1: The photosensitive unit array is packaged separately or packaged with other layers (such as pixel circuits, microlens arrays, etc.) to form an image sensor 310, and the polarizing film is attached to the photosensitive surface of the image sensor 310.

[0168] Option 2: The polarizing film is integrated within the image sensor 310. Specifically, the polarizing film and the photosensitive unit array are integrated and packaged together to form the image sensor 310. The image sensor 310 then includes a stacked photosensitive unit array and a polarizing film. For example, the packaging layer can be at least a sequentially stacked photosensitive unit array, pixel circuit (pixel light-shielding layer), and polarizing film. Alternatively, the packaging layer can also be at least a sequentially stacked pixel circuit, photosensitive unit array, and polarizing film. Furthermore, the image sensor 310 may also have a microlens array stacked above the polarizing film (in this case, the aforementioned lens group 330 may be selectively provided or omitted).

[0169] In another aspect of the embodiments of this application, an image acquisition device is provided, which will be described below.

[0170] The image acquisition device includes the light source of any of the foregoing and / or the image receiver 300 of any of the foregoing.

[0171] In another aspect, embodiments of this application provide an electronic device, such as... Figure 14 As shown, the image acquisition device includes the main body of the device and the above-mentioned parts. The image acquisition device includes a light emitting device and a receiving device arranged along the optical path. The light emitting device is any of the above-mentioned light sources, and the receiving device is any of the above-mentioned image receivers 300 (excluding the image receiver 300 where the polarizer 320 is located between the lens group 330 and the image sensor 310; in other words, the polarizer 320 in the image acquisition device should at least not be located between the lens group 330 and the image sensor 310).

[0172] Please refer to the reference. Figure 14 and Figure 15 As shown, the main body of the device includes a display screen 420, which includes a display module 421 and a light-transmitting cover plate 422. The display module 421 refers to the electronic module capable of displaying images, which typically has two opposing surfaces, one of which serves as the display side and the other as the non-display side. The light-transmitting cover plate 422 is mainly attached to the display side of the display module 421, and its material is typically glass (suitable for rigid screens) or a light-transmitting flexible material (suitable for flexible screens), used to protect the display side of the display module 421.

[0173] Please continue to refer to the reference. Figure 14 and Figure 15As shown, in order to achieve image acquisition while increasing the screen-to-body ratio, the display module 421 has a light channel 423 extending from the display side to the non-display side (i.e., the cutout portion in the display screen 420). The light-emitting element 200 and the image sensor 310 of the image acquisition device are both located on the non-display side of the display module 421, and at least one of the light-emitting element 200 and the image sensor 310 corresponds to the opening of the light channel 423 on the non-display side. This allows the linearly polarized light emitted by the light-emitting element 200 to smoothly exit from the light-transmitting cover plate 422 through the light channel 423 to the target object, and then, after being reflected by the target object, to smoothly pass through the light-transmitting cover plate 422 and the light channel 423 to enter the image sensor 310. It should be understood that the number of light channels 423 can be one or more, for example, multiple light-emitting elements 200 sharing the same light channel 423, or the light-emitting element 200 and the image sensor 310 sharing the same light channel 423, or each light-emitting element 200 and the image sensor 310 corresponding to a separate light channel 423 (e.g., ...). Figure 15 (As shown).

[0174] like Figure 15 As shown, a polarizer 320 can be directly formed in the area of ​​the light-transmitting cover plate 422 at the light channel 423. For example, before assembling the display screen 420, a second micro-nano grating 321 can be fabricated in a portion of the light-transmitting cover plate 422. The second micro-nano grating 321 and the corresponding light-transmitting cover plate 422 (as a carrier plate 380) form the aforementioned polarizer 320. The area of ​​the light-transmitting cover plate 422 with the second micro-nano grating 321 corresponds to the opening of the subsequent light channel 423. In addition, the polarizer 320 can also be fixed to the light-transmitting cover plate 422 by bridging or surface bonding.

[0175] In another aspect, this application provides an electronic device, including a device body and an image acquisition device. The image acquisition device includes a light-emitting device and a receiving device arranged along an optical path, wherein the light-emitting device is any of the above-mentioned light sources.

[0176] The main body of the device includes a display screen 420, which comprises a display module 421 and a light-transmitting cover plate 422. The display module 421 refers to the electronic module capable of displaying images, and it typically has two opposing surfaces, one of which serves as the display side, while the opposite surface serves as the non-display side. The light-transmitting cover plate 422 is mainly attached to the display side of the display module 421, and its material is typically glass (suitable for rigid screens) or a light-transmitting flexible material (suitable for flexible screens), used to protect the display side of the display module 421.

[0177] To achieve image acquisition while increasing the screen-to-body ratio, the display module 421 has a light channel 423 extending from the display side to the non-display side (i.e., the cutout portion in the display screen 420). The light-emitting element 200 and the receiving device of the image acquisition device are both located on the non-display side of the display module 421, and at least one of the light-emitting element 200 and the receiving device corresponds to the opening of the light channel 423 on the non-display side. This allows the linearly polarized light emitted by the light-emitting element 200 to smoothly exit from the light-transmitting cover plate 422 through the light channel 423 to the target object, and then, after being reflected by the target object, to smoothly pass through the light-transmitting cover plate 422 and the light channel 423 to enter the receiving device. It should be understood that the number of light channels 423 can be one or more. For example, multiple light-emitting elements 200 may share the same light channel 423, or the light-emitting element 200 and the receiving device may share the same light channel 423, or each light-emitting element 200 and the receiving device may each correspond to a separate light channel 423.

[0178] In another aspect of this application, an electronic device is provided, including a device body and an image acquisition device. The image acquisition device includes a light-emitting device and a receiving device arranged along the optical path, wherein the receiving device is the aforementioned partial image receiver 300 (excluding the image receiver 300 located between the lens group 330 and the image sensor 310 by the polarizer 320).

[0179] The main body of the device includes a display screen 420, which comprises a display module 421 and a light-transmitting cover plate 422. The display module 421 refers to the electronic module capable of displaying images, and it typically has two opposing surfaces, one of which serves as the display side, while the opposite surface serves as the non-display side. The light-transmitting cover plate 422 is mainly attached to the display side of the display module 421, and its material is typically glass (suitable for rigid screens) or a light-transmitting flexible material (suitable for flexible screens), used to protect the display side of the display module 421.

[0180] To achieve image acquisition while increasing the screen-to-body ratio, the display module 421 has a light channel 423 extending from the display side to the non-display side (i.e., the cutout portion in the display screen 420). The light-emitting device and image sensor 310 of the image acquisition device are both located on the non-display side of the display module 421, and at least one of the light-emitting device and image sensor 310 corresponds to the opening of the light channel 423 on the non-display side. This allows the linearly polarized light emitted by the light-emitting device to smoothly pass through the light channel 423 from the light-transmitting cover plate 422 to the target object, and then, after being reflected by the target object, smoothly pass through the light-transmitting cover plate 422 and the light channel 423 to enter the image sensor 310. It should be understood that the number of light channels 423 can be one or more. For example, multiple sub-light-emitting devices in the light-emitting device may share the same light channel 423, or the light-emitting device and image sensor 310 may share the same light channel 423, or each sub-light-emitting device and image sensor 310 may each correspond to a separate light channel 423.

[0181] At this point, a polarizer 320 can be directly formed in the area of ​​the light-transmitting cover plate 422 at the light channel 423. For example, before assembling the display screen 420, a second micro-nano grating 321 can be fabricated in a portion of the light-transmitting cover plate 422. The second micro-nano grating 321 and the corresponding light-transmitting cover plate 422 (as a carrier plate 380) form the aforementioned polarizer 320. The area of ​​the light-transmitting cover plate 422 with the second micro-nano grating 321 corresponds to the opening of the subsequent light channel 423. In addition, the polarizer 320 can also be fixed to the light-transmitting cover plate 422 by bridging or surface bonding.

[0182] In another aspect, embodiments of this application provide an electronic device, such as... Figure 14 As shown, the device includes a main body and any of the above-mentioned image acquisition devices, with the image acquisition device disposed on the main body.

[0183] The aforementioned electronic devices may specifically include mobile phones, tablets, televisions, laptops, smart home devices (e.g., smart air conditioners, smart refrigerators, smart speakers, smart lights or smart curtains), wearable electronic devices, in-vehicle devices (also known as vehicle infotainment systems), virtual reality devices, etc., and this application does not impose any restrictions on them.

[0184] For example Figure 14As shown, a mobile phone is illustrated, which includes a main body and the aforementioned image acquisition device. The main body includes a back panel, a mid-frame 410, a motherboard, a battery, and a display screen 420. The back panel and the display screen 420 are respectively mounted on opposite sides of the mid-frame 410 so that the three enclose an internal space. The motherboard and the battery can be located within this internal space. The battery is used to power the motherboard, the image acquisition device, and the display screen 420. The display screen 420 has a cutout portion, and the cutout position is aligned with the position of the light-emitting element 200 and the image receiver 300 in the image acquisition device.

[0185] Another aspect of this application provides a three-dimensional imaging method that can be applied to the aforementioned image acquisition device, the method comprising:

[0186] S10: Control the image sensor 310 to receive multiple linearly polarized lights in a preset timing sequence and form multiple polarization images, wherein any two linearly polarized lights have different polarization directions.

[0187] S20: Based on multiple polarization images, obtain the polarization information corresponding to each pixel in the image sensor 310.

[0188] S30: Based on the polarization information corresponding to each pixel in the image sensor 310 and the preset mapping relationship between each pixel in the image sensor 310 and each micro-element in the target object, the normal vector information of each micro-element in the target object is obtained.

[0189] S40: Based on the normal vector information of each micro-element in the target object and the position information of each pixel, the three-dimensional contour information of the target object is obtained.

[0190] Image sensor 310 receives linearly polarized light with different polarization directions sequentially in chronological order (linearly polarized light with the same polarization direction is emitted at the same time, so the image sensor 310 receives it at the same time, thus forming only one polarization image), in order to generate multiple polarization images. By utilizing the characteristic that different points in the target object change the polarization state of light to different degrees, polarization information can be obtained by comprehensively analyzing multiple polarization images. Specifically, the polarization images are mapped to each pixel of the image sensor 310, and the polarization information corresponding to each pixel is obtained by comprehensively analyzing the brightness information at the same pixel in multiple polarization images.

[0191] Since the light received by each pixel comes from different positions on the surface of the target object, the normal vector information of each micro-element in the target object is obtained through the preset mapping relationship between each pixel in the image sensor 310 and each micro-element (different positions in the target object). In this way, the three-dimensional contour information of the target object can be obtained based on the normal vector information of each micro-element in the target object and the position information of each pixel, thereby reconstructing the contour surface of the target object.

[0192] Another aspect of this application provides a face recognition method, the method comprising:

[0193] S60: Control the image sensor 310 to receive multiple linearly polarized lights in a preset timing sequence and form multiple polarization images. The linearly polarized light emitted by the light source is reflected by the target object and then enters the image sensor 310. Any two linearly polarized lights have different polarization directions. The pixel values ​​of the polarization images contain polarization information corresponding to the contour plane of the target object.

[0194] Since linearly polarized light is emitted sequentially in chronological order, the image sensor 310 can receive each linearly polarized light beam sequentially in chronological order to generate multiple polarized images. Taking advantage of the different degrees of change in the polarization state of light at different points in the face 100 (i.e., the target object), each pixel value in the polarized image contains its corresponding polarization information, and each polarization information corresponds to the contour surface of the face 100. In other words, the contour surface of the face 100 can be represented by multiple polarized images.

[0195] S70: Perform face recognition based on multiple polarization images and obtain face recognition results. Face recognition includes face matching and / or anti-spoofing recognition.

[0196] Because multiple polarization images can characterize the corresponding facial contours, facial recognition can be performed using these images to obtain the recognition result. Specifically, facial recognition based on multiple polarization images can involve verifying face matching and / or verifying against forgery. When face matching verification is included, the recognition result will include whether the face matches. Similarly, when verification against forgery is included, the result will indicate whether the face is a real face or a forgery such as a photograph, video, or silicone face mold.

[0197] When performing face matching verification, multiple polarization images and base database images can be input into the first neural network model to obtain the result of whether the face matches.

[0198] When verifying anti-counterfeiting identification, multiple polarized images can be input into the second neural network model to obtain the anti-counterfeiting results of whether it is a real face 100 or a counterfeit such as a photo, video, or face 100 silicone mold.

[0199] The base image is a pre-stored image that represents accurate facial information.

[0200] In addition, when performing face recognition, the aforementioned three-dimensional imaging method can be used to obtain the three-dimensional contour information of the face from multiple polarized images, and then the face recognition result can be obtained through the three-dimensional contour information. Of course, this face recognition method can still include face matching verification and / or anti-counterfeiting verification.

[0201] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A light source, characterized in that, include: A light-emitting element having at least two polarization structures emits linearly polarized light in at least two polarization directions after being modulated by the at least two polarization structures. The linearly polarized light in the at least two polarization directions is reflected by the target object and then sequentially incident on an image receiver.

2. The light source as described in claim 1, characterized in that, For linearly polarized light with different polarization directions, the light-emitting element emits light in chronological order.

3. The light source as described in claim 1, characterized in that, At least a portion of the polarization structure is placed inside the light-emitting element and / or on the light-emitting surface.

4. The light source as described in claim 1, characterized in that, The light-emitting element includes at least two light-emitting units; The light-emitting unit and the polarization structure have a one-to-one modulation relationship, or at least two of the light-emitting units share the same polarization structure.

5. The light source according to any one of claims 1 to 4, characterized in that, The polarization directions of any two polarization structures are different; Alternatively; the light-emitting element has at least three polarization structures, at least two of which have different polarization directions, and some of which have the same polarization direction.

6. The light source according to any one of claims 1 to 4, characterized in that, The light-emitting element includes at least two light-emitting units, the light-emitting element is a laser device, and the light-emitting unit is the optical resonant cavity of the laser device; At least a portion of the polarization structure is placed inside the optical resonant cavity or on the light-emitting surface.

7. The light source as described in claim 6, characterized in that, At least two optical resonators share the same substrate, and there is an isolation region between adjacent optical resonators.

8. The light source as described in claim 6, characterized in that, The laser device includes a first electrode and at least two second electrodes, wherein the at least two optical resonators share the first electrode, and the at least two second electrodes are respectively configured to correspond one-to-one with the at least two optical resonators.

9. The light source according to any one of claims 1 to 4, characterized in that, The light source also includes a packaging structure for encapsulating the light-emitting element.

10. The light source as described in claim 9, characterized in that, The encapsulation structure has a diffuser located on the light-emitting side of the light-emitting element.

11. The light source according to any one of claims 1 to 4, characterized in that, In the at least two polarization structures of the light-emitting element, at least two of the polarization structures have an angle between their polarization directions of 45° and 135°, or any two of the polarization structures have an angle between their polarization directions of 45° and 135°.

12. The light source as described in claim 11, characterized in that, The light-emitting element includes two polarization structures, and the included angle between the polarization directions of the two polarization structures is 45° to 135°.

13. The light source as described in claim 12, characterized in that, The polarization directions of the two polarization structures are perpendicular to each other.

14. The light source as described in claim 13, characterized in that, The light source also includes a packaging structure for encapsulating the light-emitting element. The linearly polarized light is emitted through the light-emitting side surface of the packaging structure. The peripheral contour of the light-emitting side surface has a plurality of straight edges, and the polarization direction of one of the polarization structures is parallel to at least one of the straight edges.

15. The light source according to any one of claims 1 to 4, characterized in that, The light-emitting element emits light at a wavelength of 940nm.

16. An image receiver, characterized in that, The device includes an image sensor and a polarizer. The image sensor includes a photosensitive unit array, and the polarizer is disposed on the light-incident side of the photosensitive unit array. The polarization direction of the polarizer forms an angle less than or equal to the target angle with one of the polarization directions of the polarization structure of the light-emitting element. The light-emitting element has at least two polarization structures, and after being modulated by the at least two polarization structures, the light-emitting element sequentially emits linearly polarized light in at least two polarization directions. The linearly polarized light in the at least two polarization directions is reflected by the target object and then sequentially incident on the image receiver.

17. The image receiver as claimed in claim 16, characterized in that, The target angle is 5°, 10°, 15°, 20°, 25° or 30°.

18. The image receiver as claimed in claim 16 or 17, characterized in that, The polarization direction of the polarizer is the same as one of the polarization directions of the polarization structure of the light-emitting element.

19. The image receiver as claimed in claim 16 or 17, characterized in that, The image receiver also includes: A lens group, located on the light-receiving side of the image sensor; A filter unit is located between the lens group and the image sensor; The polarizing element is a polarizer, wherein the polarizer is located on the side of the lens group away from the image sensor, and the filter unit and the polarizer are separate components; or, the polarizer is located between the lens group and the image sensor.

20. The image receiver as claimed in claim 19, characterized in that, When the polarizer is located between the lens group and the image sensor, the polarizer is located between the filter unit and the image sensor; The polarizer has a second micro-nano grating; The peripheral edge of the polarizer is connected to the image sensor via a bridge structure to form a gap between the polarizer and the image sensor to accommodate the second micro-nano grating. Alternatively, the polarizer may also have a protective layer covering the second micro-nano grating, which is bonded to the image sensor via an adhesive layer.

21. The image receiver as claimed in claim 19, characterized in that, When the polarizer is located between the lens group and the image sensor, the filter unit and the polarizer are separate components; or, the filter unit is a filter, and the filter and the polarizer share the same carrier plate and are respectively formed on opposite sides of the carrier plate.

22. The image receiver as claimed in claim 16 or 17, characterized in that, The polarizing element is a polarizing film or a metal wire grid, which is integrated into the image sensor.

23. An image acquisition device, characterized in that, It includes a light-emitting device and a receiving device arranged along the optical path, wherein the light-emitting device is a light source as described in any one of claims 1 to 15, and / or the receiving device is an image receiver as described in any one of claims 16 to 22.

24. An electronic device, characterized in that, It includes a main body of the device and an image acquisition device as described in claim 23, wherein the image acquisition device is disposed on the main body of the device.

25. An electronic device, characterized in that, The device includes a main body and an image acquisition device. The image acquisition device includes a light-emitting device and a receiving device arranged along the optical path. The light-emitting device is a light source as described in any one of claims 1 to 15, and / or the receiving device is an image receiver as described in any one of claims 16 to 22. The main body of the device includes a display screen, which includes a display module and a light-transmitting cover plate attached to the display side of the display module. The display module has a light channel extending from the display side to the non-display side. The light-emitting element and / or image sensor of the image acquisition device correspond to the opening of the light channel on the non-display side. The polarizing element of the image acquisition device is disposed on the light-transmitting cover plate and located at the opening of the light channel on the display side.

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