Fingerprint recognition method, fingerprint recognition device and electronic device

Abstract

Provided are a method for identifying fingerprints, a fingerprint identification device, and an electronic device. The method comprises: obtaining optical signals from multiple directions reflected by a sampling entity above a display screen; generating multiple two-dimensional (2D) fingerprint images based on the optical signals from multiple directions; determining whether the sampling entity is a three-dimensional (3D) entity based on the multiple 2D fingerprint images; and, if the sampling entity is a 3D entity, performing fingerprint identification based on at least one of the multiple 2D fingerprint images. The optical signals from multiple directions effectively distinguish between 2D and 3D entities, and subsequent fingerprint identification is performed when the sampling entity is a 3D entity. This fundamentally avoids fingerprint identification based on false fingerprints collected from 2D entities, thereby improving the security of fingerprint identification.

Description

[0001] This application is a divisional application of the invention patent application with the application date of October 21, 2019, application number 201980002364.4, and name “Method for identifying fingerprints, fingerprint identification device and electronic device”. Technical Field

[0002] The embodiments of the present application relate to the field of under-screen fingerprint recognition, and more specifically, to a method for recognizing fingerprints, a fingerprint recognition device, and an electronic device. Background Art

[0003] Optical fingerprint recognition technology carries the risk of misidentification. For example, a fake fingerprint containing partial fingerprint information is placed at the sampling location, and light and shadow imaging is used to generate a fingerprint image to be matched. When the fingerprint image successfully matches the template in the library, the "unlock" operation is completed.

[0004] Since there are many ways to obtain personal fingerprint information, and 2D fingerprint image molds have clear fingerprint features and low production costs, the fingerprint recognition solution based on 2D fingerprint images has great security risks.

[0005] Currently, fingerprint recognition security is improved by detecting whether the sampling entity placed above the display screen is a live finger. For example, heart rate detection technology or filter recognition technology can be used to determine whether the sampling entity is a live finger. Heart rate detection technology determines whether the sampling entity has a heart rate to identify whether the sampling entity is a fake fingerprint. Filter recognition technology uses filters of different wavelengths to identify whether the sampling entity is a fake fingerprint based on the color of the collected fingerprint image.

[0006] However, the cost of heart rate detection technology is high and the requirements for implementation scenarios are high, and the accuracy of the filtering recognition technology is low.

[0007] Therefore, there is an urgent need for a technical solution that can improve the security of optical fingerprint recognition.

[0008] Application Contents

[0009] Provided are a fingerprint recognition method, a fingerprint recognition device, and an electronic device, which can improve the security of optical fingerprint recognition.

[0010] In a first aspect, a method for identifying fingerprints is provided, which is applicable to an electronic device with a display screen to implement under-screen fingerprint recognition. The method includes:

[0011] Acquire light signals in multiple directions reflected by a sampling entity above the display screen;

[0012] Based on the light signals in the multiple directions, generate multiple two-dimensional 2D fingerprint images respectively;

[0013] Determining whether the sampled entity is a three-dimensional (3D) entity based on the multiple 2D fingerprint images;

[0014] If the sampled entity is a 3D entity, fingerprint recognition is performed based on at least one 2D fingerprint image among the multiple 2D fingerprint images.

[0015] In short, the optical signals in multiple directions effectively distinguish between 2D entities and 3D entities, and when the sampled entity is a 3D entity, subsequent fingerprint recognition is performed, thereby fundamentally avoiding fingerprint recognition based on false fingerprints collected from 2D entities, thereby improving the security of fingerprint recognition.

[0016] In some possible implementations, determining whether the sampled entity is a three-dimensional (3D) entity based on the multiple 2D fingerprint images includes:

[0017] determining whether the multiple 2D fingerprint images are identical;

[0018] If the multiple 2D fingerprint images are different, the sampled entity is determined to be a 3D entity.

[0019] In some possible implementations, determining whether the multiple 2D fingerprint images are identical includes:

[0020] If the curvatures of the same image texture of the multiple 2D fingerprint images are different, determining that the multiple 2D fingerprint images are different; and / or

[0021] If the widths of the lines of the same image in the multiple 2D fingerprint images are different, it is determined that the multiple 2D fingerprint images are different.

[0022] In some possible implementations, performing fingerprint recognition based on at least one 2D fingerprint image among the multiple 2D fingerprint images includes:

[0023] generating a target 2D fingerprint image based on the multiple 2D fingerprint images, wherein the image texture of the target 2D fingerprint image includes image textures where the multiple 2D fingerprint images overlap with each other;

[0024] Fingerprint recognition is performed based on the target 2D fingerprint image.

[0025] In some possible implementations, performing fingerprint recognition based on the target 2D fingerprint image includes:

[0026] If the target 2D fingerprint image matches the pre-stored 2D fingerprint image, the fingerprint recognition is determined to be successful; and / or

[0027] If the target 2D fingerprint image fails to match the pre-stored 2D fingerprint image, it is determined that the fingerprint recognition has failed.

[0028] In some possible implementations, performing fingerprint recognition based on the target 2D fingerprint image includes:

[0029] generating a target 3D fingerprint image based on the target 2D fingerprint image;

[0030] Fingerprint recognition is performed based on the target 3D fingerprint image.

[0031] In some possible implementations, generating a target 3D fingerprint image based on the target 2D fingerprint image includes:

[0032] determining, based on the target 2D fingerprint image and a first 2D fingerprint image among the multiple 2D fingerprint images, a height of each line unit on each image line in the target 2D fingerprint image;

[0033] The target 3D fingerprint image is generated based on the height of each line unit on each image line in the target 2D fingerprint image.

[0034] In some possible implementations, determining the height of each grain unit on each image grain in the target 2D fingerprint image based on the target 2D fingerprint image and a first 2D fingerprint image among the multiple 2D fingerprint images includes:

[0035] For each line element on each line in the target 2D fingerprint image, subtract the width of the same line element on the same line in the target 2D fingerprint image from the width of each line element on each line in the first 2D fingerprint image to obtain a target width corresponding to each line element on each line in the target 2D fingerprint image;

[0036] The height of each line unit on each line in the target 2D fingerprint image is determined based on the target width corresponding to each line unit on each line in the target 2D fingerprint image.

[0037] In some possible implementations, determining the height of each grain unit on each image grain in the target 2D fingerprint image based on a target width corresponding to each grain unit on each image grain in the target 2D fingerprint image includes:

[0038] The height of each line unit on each line in the target 2D fingerprint image is determined according to the following formula:

[0039] H = K × d × tanθ;

[0040] Wherein, H represents the height of the texture unit on the image texture in the target 2D fingerprint image, K represents the reduction ratio of the projection of the sampling entity on the display screen to the first 2D fingerprint image, d represents the target width, and θ represents the angle between the light signal used to form the first 2D fingerprint image in the multiple directions of light signals and the finger spine.

[0041] In some possible implementations, performing fingerprint recognition based on the target 3D fingerprint image includes:

[0042] If the target 3D fingerprint image matches the pre-stored 3D fingerprint image, the fingerprint recognition is determined to be successful; and / or

[0043] If the target 3D fingerprint image fails to match the pre-stored 3D fingerprint image, it is determined that the fingerprint recognition has failed.

[0044] Optionally, in some possible implementations, the light signals in multiple directions include light signals perpendicular to the display screen and light signals tilted relative to the display screen; or the light signals in multiple directions include light signals tilted relative to the display screen.

[0045] In a second aspect, a fingerprint recognition device is provided. The fingerprint recognition device is applicable to an electronic device having a display screen and is disposed below the display screen to implement under-screen fingerprint recognition.

[0046] The fingerprint recognition device comprises:

[0047] an optical sensing pixel array, the optical sensing pixel array being configured to acquire light signals in multiple directions reflected by a sampling entity above the display screen;

[0048] A processor connected to the optical sensing pixel array, wherein the processor is configured to:

[0049] receiving the optical signals in the multiple directions sent by the optical sensing pixel array, and generating a plurality of two-dimensional 2D fingerprint images based on the optical signals in the multiple directions;

[0050] Determining whether the sampled entity is a three-dimensional (3D) entity based on the multiple 2D fingerprint images;

[0051] If the sampled entity is a 3D entity, fingerprint recognition is performed based on at least one 2D fingerprint image among the multiple 2D fingerprint images.

[0052] Optionally, in some possible implementations, the processor is specifically configured to:

[0053] determining whether the multiple 2D fingerprint images are identical;

[0054] If the multiple 2D fingerprint images are different, the sampled entity is determined to be a 3D entity.

[0055] In some possible implementations, the processor is further configured to:

[0056] If the curvatures of the same image texture of the multiple 2D fingerprint images are different, determining that the multiple 2D fingerprint images are different; and / or

[0057] If the widths of the lines of the same image in the multiple 2D fingerprint images are different, it is determined that the multiple 2D fingerprint images are different.

[0058] In some possible implementations, the processor is specifically configured to:

[0059] generating a target 2D fingerprint image based on the multiple 2D fingerprint images, wherein the image texture of the target 2D fingerprint image includes image textures where the multiple 2D fingerprint images overlap with each other;

[0060] Fingerprint recognition is performed based on the target 2D fingerprint image.

[0061] In some possible implementations, the processor is further configured to:

[0062] If the target 2D fingerprint image matches the pre-stored 2D fingerprint image, the fingerprint recognition is determined to be successful; and / or

[0063] If the target 2D fingerprint image fails to match the pre-stored 2D fingerprint image, it is determined that the fingerprint recognition has failed.

[0064] In some possible implementations, the processor is further configured to:

[0065] generating a target 3D fingerprint image based on the target 2D fingerprint image;

[0066] Fingerprint recognition is performed based on the target 3D fingerprint image.

[0067] In some possible implementations, the processor is further configured to:

[0068] determining, based on the target 2D fingerprint image and a first 2D fingerprint image among the multiple 2D fingerprint images, a height of each line unit on each image line in the target 2D fingerprint image;

[0069] The target 3D fingerprint image is generated based on the height of each line unit on each image line in the target 2D fingerprint image.

[0070] In some possible implementations, the processor is further configured to:

[0071] For each line element on each line in the target 2D fingerprint image, subtract the width of the same line element on the same line in the target 2D fingerprint image from the width of each line element on each line in the first 2D fingerprint image to obtain a target width corresponding to each line element on each line in the target 2D fingerprint image;

[0072] The height of each line unit on each line in the target 2D fingerprint image is determined based on the target width corresponding to each line unit on each line in the target 2D fingerprint image.

[0073] In some possible implementations, the processor is further configured to:

[0074] The height of each line unit on each line in the target 2D fingerprint image is determined according to the following formula:

[0075] H = K × d × tanθ;

[0076] Wherein, H represents the height of the same texture unit on the same image texture in the target 2D fingerprint image, K represents the reduction ratio of the projection of the sampling entity on the display screen to the 2D fingerprint image in the multiple 2D fingerprint images, d represents the target width, and θ represents the angle between the light signal used to form the first 2D fingerprint image in the multiple directions of light signals and the finger spine.

[0077] Optionally, in some possible implementations, the processor is further configured to:

[0078] If the target 3D fingerprint image matches the pre-stored 3D fingerprint image, the fingerprint recognition is determined to be successful; and / or

[0079] If the target 3D fingerprint image fails to match the pre-stored 3D fingerprint image, it is determined that the fingerprint recognition has failed.

[0080] In some possible implementations, the optical signals in multiple directions include optical signals perpendicular to the display screen and optical signals tilted relative to the display screen; or the optical signals in multiple directions include optical signals tilted relative to the display screen.

[0081] According to a third aspect, an electronic device is provided, including:

[0082] Display screen; and

[0083] The fingerprint recognition device described in the second aspect or any possible implementation of the second aspect, wherein the fingerprint recognition device is arranged below the display area of ​​the display screen to realize under-screen fingerprint recognition. BRIEF DESCRIPTION OF THE DRAWINGS

[0084] Figure 1 It is a schematic structural diagram of an electronic device to which the present application can be applied.

[0085] Figure 2 yes Figure 1 A cross-sectional schematic diagram of the electronic device shown.

[0086] Figure 3 is another schematic structural diagram of an electronic device to which the present application can be applied.

[0087] Figure 4 yes Figure 3 A cross-sectional schematic diagram of the electronic device shown.

[0088] Figures 5 to 33 A schematic structural diagram of a fingerprint detection device according to an embodiment of the present application.

[0089] Figures 34 to 36 It is a schematic structural diagram of the fingerprint detection system of an embodiment of the present application.

[0090] Figure 37 It is a schematic flow chart of the fingerprint recognition method according to an embodiment of the present application.

[0091] Figure 38 3 is a schematic structural diagram of optical signals received in two directions by the fingerprint detection device according to an embodiment of the present application.

[0092] Figure 39 2D fingerprint image obtained by the fingerprint detection device when the sampling entity is a 2D entity according to an embodiment of the present application.

[0093] Figure 40 and Figure 41 They are schematic diagrams of 2D fingerprint images acquired by the fingerprint detection device when the sampling entity is a 3D entity according to an embodiment of the present application.

[0094] Figure 42 This embodiment of the present application is based on Figure 40 and Figure 41 Schematic diagram of a target 2D fingerprint image obtained by the 2D fingerprint image shown.

[0095] Figure 43 This embodiment of the present application is based on Figure 42 Schematic diagram of image patterns in a target 3D fingerprint image obtained from a target 2D fingerprint image shown.

[0096] Figure 44 yes Figure 41 Schematic diagram of the width of image lines in the 2D fingerprint image shown.

[0097] Figure 45 It is a schematic block diagram of a fingerprint detection device according to an embodiment of the present application. DETAILED DESCRIPTION

[0098] The technical solution in this application will be described below with reference to the accompanying drawings.

[0099] The technical solutions of the embodiments of the present application can be applied to various electronic devices. For example, portable or mobile computing devices such as smartphones, laptops, tablet computers, and gaming devices, as well as other electronic devices such as electronic databases, automobiles, and bank automated teller machines (ATMs), are not limited thereto.

[0100] The technical solutions of the embodiments of the present application can be used in biometric recognition technology. Biometric recognition technology includes, but is not limited to, fingerprint recognition, palm print recognition, iris recognition, face recognition, and liveness recognition. For ease of explanation, the following description uses fingerprint recognition technology as an example.

[0101] The technical solutions of the embodiments of the present application can be used for both under-screen fingerprint recognition technology and in-screen fingerprint recognition technology.

[0102] Under-screen fingerprint recognition technology refers to installing a fingerprint recognition module under the display screen, so as to realize fingerprint recognition operation within the display area of ​​the display screen, and there is no need to set a fingerprint collection area in the area other than the display area on the front of the electronic device. Specifically, the fingerprint recognition module uses the light returned from the top surface of the display component of the electronic device to perform fingerprint sensing and other sensing operations. This returned light carries information about an object (such as a finger) that is in contact with or close to the top surface of the display component, and the fingerprint recognition module located below the display component collects and detects this returned light to realize under-screen fingerprint recognition. Among them, the design of the fingerprint recognition module can be to achieve the desired optical imaging by properly configuring the optical elements for collecting and detecting the returned light, thereby detecting the fingerprint information of the finger.

[0103] Correspondingly, in-display fingerprint recognition technology refers to installing the fingerprint recognition module or part of the fingerprint recognition module inside the display screen, so as to realize fingerprint recognition operation within the display area of ​​the display screen, without the need to set up a fingerprint collection area in the area other than the display area on the front of the electronic device.

[0104] Figures 1 to 4 A schematic diagram of an electronic device to which the embodiments of the present application are applicable is shown. Figure 1and Figure 3 is a schematic diagram of the orientation of the electronic device 10, Figure 2 and Figure 4 They are Figure 1 and Figure 3 FIG. 1 is a schematic cross-sectional view of an electronic device 10 .

[0105] See Figures 1 to 4 , the electronic device 10 may include a display screen 120 and an optical fingerprint recognition module 130 .

[0106] Among them, the display screen 120 can be a self-luminous display screen, which uses a display unit with self-luminescence as a display pixel. For example, the display screen 120 can be an organic light-emitting diode (OLED) display screen or a micro-light-emitting diode (Micro-LED) display screen. In other alternative embodiments, the display screen 120 can also be a liquid crystal display (LCD) or other passive light-emitting display screen, and the embodiments of the present application are not limited to this. Furthermore, the display screen 120 can also be specifically a touch display screen, which can not only display images, but also detect user touch or press operations, thereby providing a human-computer interaction interface for the user. For example, in one embodiment, the electronic device 10 may include a touch sensor, and the touch sensor can be specifically a touch panel (TP), which can be arranged on the surface of the display screen 120, or can be partially integrated or wholly integrated into the interior of the display screen 120, thereby forming the touch display screen.

[0107] The optical fingerprint module 130 includes an optical fingerprint sensor, which includes a sensing array 133 having multiple optical sensing units 131 (also referred to as optical sensing pixels, photosensitive pixels, pixel units, etc.). The area where the sensing array 133 is located or its sensing area is the fingerprint detection area 103 (also referred to as the fingerprint collection area, fingerprint recognition area, etc.) of the optical fingerprint module 130. For example, the optical sensing unit 131 can be a photodetector, that is, the sensing array 133 can specifically be a photodetector array, which includes multiple photodetectors distributed in an array.

[0108] The optical fingerprint module 130 is disposed in a local area below the display screen 120 .

[0109] Please continue to see Figure 1, the fingerprint detection area 103 can be located within the display area of ​​the display screen 120. In an alternative embodiment, the optical fingerprint module 130 can also be set at other locations, such as the side of the display screen 120 or the non-light-transmitting area at the edge of the electronic device 10, and the optical path design can be used to guide the light signal from at least part of the display area of ​​the display screen 120 to the optical fingerprint module 130, so that the fingerprint detection area 103 is actually located in the display area of ​​the display screen 120.

[0110] When a user needs to unlock the electronic device 10 or perform other fingerprint verification, they only need to press their finger on the fingerprint detection area 103 located on the display screen 120 to input a fingerprint. Because fingerprint detection can be performed within the display, the electronic device 10 using the above structure does not need to reserve space on the front of the electronic device 10 for a fingerprint button (such as the Home button). This allows the use of a full-screen solution, that is, the display area of ​​the display screen 120 can be substantially extended to the entire front of the electronic device 10.

[0111] Please continue to see Figure 2 , the optical fingerprint module 130 may include a light detection part 134 and an optical component 132. The light detection part 134 includes the sensing array 133 (also called an optical fingerprint sensor) and a reading circuit and other auxiliary circuits electrically connected to the sensing array 133, which can be manufactured on a chip (Die) through a semiconductor process, such as an optical imaging chip or an optical fingerprint sensor. The optical component 132 can be arranged above the sensing array 133 of the light detection part 134, and can specifically include a filter layer (Filter), a light guide layer or a light path guiding structure, and other optical elements. The filter layer can be used to filter out the ambient light that penetrates the finger, and the light guide layer or light path guiding structure is mainly used to guide the reflected light reflected from the finger surface to the sensing array 133 for optical detection.

[0112] In some embodiments of the present application, the optical component 132 can be packaged in the same optical fingerprint component as the light detection part 134. For example, the optical component 132 can be packaged in the same optical fingerprint chip as the optical detection part 134, or the optical component 132 can be arranged outside the chip where the light detection part 134 is located, such as attaching the optical component 132 above the chip, or integrating some components of the optical component 132 into the above chip.

[0113] In some embodiments of the present application, the area where the sensing array 133 of the optical fingerprint module 130 is located or the light sensing range corresponds to the fingerprint detection area 103 of the optical fingerprint module 130. The fingerprint detection area 103 of the optical fingerprint module 130 may be equal to or different from the area or light sensing range of the area where the sensing array 133 of the optical fingerprint module 130 is located, and this embodiment of the present application does not specifically limit this.

[0114] For example, by guiding the light path in a light collimation manner, the fingerprint detection area 103 of the optical fingerprint module 130 can be designed to be substantially consistent with the area of ​​the sensing array of the optical fingerprint module 130 .

[0115] For another example, the area of ​​the fingerprint detection area 103 of the optical fingerprint module 130 can be made larger than the area of ​​the sensing array 133 of the optical fingerprint module 130 through an optical path design such as lens imaging, a reflective folded optical path design, or other light converging or reflecting optical path designs.

[0116] The light path guiding structure that the optical component 132 may include is exemplarily described below.

[0117] Taking the optical collimator with a through-hole array with a high aspect ratio used in the light path guiding structure as an example, the optical collimator can be specifically a collimator (Collimator) layer made on a semiconductor silicon wafer, which has multiple collimating units or micropores. The collimating unit can be specifically a small hole. Among the reflected light reflected from the finger, the light perpendicularly incident on the collimating unit can pass through and be received by the sensor chip below it, while the light with an incident angle that is too large is attenuated after multiple reflections inside the collimating unit. Therefore, each sensor chip can basically only receive the reflected light reflected from the fingerprint pattern directly above it, which can effectively improve the image resolution and thus improve the fingerprint recognition effect.

[0118] Taking the optical path design of the optical lens as an example, the optical path guiding structure can be an optical lens (Lens) layer, which has one or more lens units, such as a lens group composed of one or more aspherical lenses, which is used to converge the reflected light reflected from the finger to the sensing array 133 of the light detection part 134 below it, so that the sensing array 133 can be imaged based on the reflected light, thereby obtaining the fingerprint image of the finger. Furthermore, the optical lens layer can also form a pinhole or micro-aperture diaphragm in the optical path of the lens unit. For example, one or more light-shielding sheets can be formed in the optical path of the lens unit, at least one of which can form a light-transmitting micro-aperture in the optical axis or optical center area of ​​the lens unit, and the light-transmitting micro-aperture can serve as the above-mentioned pinhole or micro-aperture diaphragm. The pinhole or micro-aperture diaphragm can cooperate with the optical lens layer and / or other optical film layers above the optical lens layer to expand the field of view of the optical fingerprint module 130 to improve the fingerprint imaging effect of the optical fingerprint module 130.

[0119] Taking the optical path design of the light path guiding structure using a micro-lens layer as an example, the light path guiding structure can be a micro-lens array formed by a plurality of micro-lenses, which can be formed above the sensing array 133 of the light detection part 134 by a semiconductor growth process or other process, and each micro-lens can correspond to one of the sensing units of the sensing array 133. In addition, other optical film layers, such as a dielectric layer or a passivation layer, can be formed between the micro-lens layer and the sensing unit. More specifically, a light-blocking layer (or light-shielding layer, light-blocking layer, etc.) having micro-holes (or openings) can be further included between the micro-lens layer and the sensing unit, wherein the micro-holes are formed between the corresponding micro-lenses and the sensing unit. The light-blocking layer can block the optical interference between adjacent micro-lenses and the sensing unit, and allows the light corresponding to the sensing unit to converge into the inside of the micro-hole through the micro-lens and be transmitted to the sensing unit via the micro-hole for optical fingerprint imaging.

[0120] It should be understood that the above-mentioned several implementation solutions for the light path guiding structure can be used alone or in combination.

[0121] For example, a microlens layer may be further provided above or below the collimator layer or the optical lens layer. Of course, when the collimator layer or the optical lens layer is used in combination with the microlens layer, the specific stacking structure or optical path may need to be adjusted according to actual needs.

[0122] On the other hand, the optical component 132 may also include other optical elements, such as a filter layer or other optical film, which may be arranged between the light path guiding structure and the optical fingerprint sensor or between the display screen 120 and the light path guiding structure, mainly used to isolate the influence of external interference light on optical fingerprint detection. Among them, the filter layer can be used to filter out the ambient light that penetrates the finger and enters the optical fingerprint sensor through the display screen 120. Similar to the light path guiding structure, the filter layer can be set separately for each optical fingerprint sensor to filter out interference light, or a large-area filter layer can be used to cover the multiple optical fingerprint sensors at the same time.

[0123] The fingerprint recognition module 130 can be used to collect the user's fingerprint information (such as fingerprint image information).

[0124] Take the example of a display screen 120 that uses a display screen with a self-luminous display unit, such as an organic light-emitting diode (OLED) display screen or a micro-LED display screen. The optical fingerprint module 130 can use the display unit (i.e., OLED light source) of the OLED display screen 120 located in the fingerprint detection area 103 as an excitation light source for optical fingerprint detection. When the finger 140 presses on the fingerprint detection area 103, the display screen 120 emits a beam of light 111 to the target finger 140 above the fingerprint detection area 103. The light 111 is reflected on the surface of the finger 140 to form reflected light or is scattered inside the finger 140 to form scattered light (transmitted light). In the relevant patent application, for the convenience of description, the above-mentioned reflected light and scattered light are collectively referred to as reflected light. Because the ridges 141 and valleys 142 of a fingerprint have different light reflectivity, the reflected light 151 from the fingerprint ridges and the reflected light 152 from the fingerprint valleys have different light intensities. After passing through the optical component 132, the reflected light is received by the sensing array 133 in the optical fingerprint module 130 and converted into a corresponding electrical signal, namely, a fingerprint detection signal. Based on the fingerprint detection signal, fingerprint image data can be obtained, and fingerprint matching verification can be further performed, thereby realizing the optical fingerprint recognition function in the electronic device 10.

[0125] In other alternatives, the optical fingerprint module 130 may also use a built-in light source or an external light source to provide the optical signal for fingerprint detection and identification. In this case, the optical fingerprint module 130 is applicable not only to self-luminous displays such as OLED displays, but also to non-self-luminous displays such as LCD displays or other passively illuminated displays.

[0126] Taking the application of a liquid crystal display with a backlight module and a liquid crystal panel as an example, to support under-screen fingerprint detection of the liquid crystal display, the optical fingerprint system of the electronic device 10 may further include an excitation light source for optical fingerprint detection. The excitation light source may be specifically an infrared light source or a light source of non-visible light of a specific wavelength. The excitation light source may be arranged below the backlight module of the liquid crystal display or in the edge area below the protective cover of the electronic device 10. The optical fingerprint module 130 may be arranged below the edge area of ​​the liquid crystal panel or the protective cover and guided through the light path so that the fingerprint detection light can reach the optical fingerprint module 130. Alternatively, the optical fingerprint module 130 may also be arranged below the backlight module, and the backlight module may allow the fingerprint detection light to pass through the liquid crystal panel and backlight module and reach the optical fingerprint module 130 by opening holes or other optical designs in film layers such as a diffuser, a brightness enhancement sheet, and a reflector. When the optical fingerprint module 130 uses a built-in light source or an external light source to provide the optical signal for fingerprint detection, its detection principle is consistent with the above description.

[0127] In a specific implementation, the electronic device 10 may further include a transparent protective cover plate, which may be a glass cover plate or a sapphire cover plate, which is located above the display screen 120 and covers the front surface of the electronic device 10. Therefore, in the embodiment of the present application, the so-called finger pressing on the display screen 120 actually refers to pressing the cover plate above the display screen 120 or the surface of the protective layer covering the cover plate.

[0128] On the other hand, the optical fingerprint module 130 may include only one optical fingerprint sensor. In this case, the fingerprint detection area 103 of the optical fingerprint module 130 is small in area and fixed in position. Therefore, when the user inputs a fingerprint, the user needs to press the finger to a specific position of the fingerprint detection area 103. Otherwise, the optical fingerprint module 130 may not be able to collect the fingerprint image, resulting in a poor user experience. In other alternative embodiments, the optical fingerprint module 130 may specifically include multiple optical fingerprint sensors. The multiple optical fingerprint sensors can be arranged side by side below the display screen 120 in a splicing manner, and the sensing areas of the multiple optical fingerprint sensors together constitute the fingerprint detection area 103 of the optical fingerprint module 130. Thus, the fingerprint detection area 103 of the optical fingerprint module 130 can be extended to the main area of ​​the lower half of the display screen, that is, to the area where the finger is usually pressed, thereby realizing a blind fingerprint input operation. Furthermore, when the number of the optical fingerprint sensors is sufficient, the fingerprint detection area 103 can also be extended to half of the display area or even the entire display area, thereby realizing half-screen or full-screen fingerprint detection.

[0129] See Figure 3 and Figure 4The optical fingerprint module 130 in the electronic device 10 may include multiple optical fingerprint sensors, which may be arranged side by side below the display screen 120 by, for example, splicing, and the sensing areas of the multiple optical fingerprint sensors together constitute the fingerprint detection area 103 of the optical fingerprint device 130.

[0130] Furthermore, the optical assembly 132 may include multiple light path guiding structures, each of which corresponds to an optical fingerprint sensor (i.e., the sensing array 133) and is respectively disposed above the corresponding optical fingerprint sensor. Alternatively, the multiple optical fingerprint sensors may share an overall light path guiding structure, i.e., the light path guiding structure has an area large enough to cover the sensing arrays of the multiple optical fingerprint sensors.

[0131] Taking the optical component 132 as an example of an optical collimator with a through-hole array having a high aspect ratio, when the optical fingerprint module 130 includes multiple optical fingerprint sensors, one or more collimating units can be configured for one optical sensing unit in the optical sensing array of each optical fingerprint sensor, and are fitted above the corresponding optical sensing unit. Of course, the multiple optical sensing units can also share one collimating unit, that is, the one collimating unit has a large enough aperture to cover multiple optical sensing units. Since one collimating unit can correspond to multiple optical sensing units or one optical sensing unit corresponds to multiple collimating units, the correspondence between the spatial period of the display screen 120 and the spatial period of the optical fingerprint sensor is destroyed. Therefore, even if the spatial structure of the light-emitting display array of the display screen 120 is similar to the spatial structure of the optical sensing array of the optical fingerprint sensor, it can effectively avoid the optical fingerprint module 130 using the light signal passing through the display screen 120 to perform fingerprint imaging to generate moiré fringes, thereby effectively improving the fingerprint recognition effect of the optical fingerprint module 130.

[0132] Taking the optical component 132 as an example, when the optical fingerprint module 130 includes multiple sensor chips, an optical lens can be configured for each sensor chip to perform fingerprint imaging, or a single optical lens can be configured for multiple sensor chips to achieve light convergence and fingerprint imaging. Even when a sensor chip has two sensing arrays (Dual Array) or multiple sensing arrays (Multi-Array), two or more optical lenses can be configured for this sensor chip to cooperate with the two sensing arrays or multiple sensing arrays for optical imaging, thereby reducing the imaging distance and enhancing the imaging effect.

[0133] It should be understood that Figures 1 to 4 This is only an example of the present application and should not be considered as limiting the present application.

[0134] For example, the present application does not specifically limit the number, size, and arrangement of fingerprint sensors, which can be adjusted according to actual needs. For example, the optical fingerprint module 130 may include multiple fingerprint sensors distributed in a square or circular shape.

[0135] It should be noted that, assuming that the optical guidance structure included in the optical component 132 is an optical collimator or a microlens array, the effective field of view of the sensing array 133 of the optical fingerprint module 130 is limited by the area of ​​the optical component. Taking the microlens array as an example, in a general design, the microlens array is located directly above or diagonally above the sensing array 133, and each microlens corresponds to one optical sensing unit, that is, each microlens in the microlens array focuses the received light onto the optical sensing unit corresponding to the same microlens. Therefore, the fingerprint recognition area of ​​the sensing array 133 is affected by the size of the microlens array.

[0136] Therefore, how to improve the area of ​​fingerprint recognition has become a technical problem that needs to be solved urgently.

[0137] The fingerprint detection device of the embodiment of the present application is applicable to the bottom of the display screen to realize the optical fingerprint detection under the screen. The fingerprint detection device can be applied to Figures 1 to 4 The electronic device 10 shown, or the device may be Figures 1 to 5 The optical fingerprint module 130 shown. Figure 5 As shown, the fingerprint detection device includes a plurality of fingerprint detection units 21.

[0138] It should be understood that the fingerprint detection device may include multiple fingerprint detection units distributed in an array or staggered, or may include multiple fingerprint detection units distributed in a centrally symmetrical or axially symmetrical manner, and the embodiments of the present application do not specifically limit this.

[0139] Each of the plurality of fingerprint detection units includes: a plurality of optical sensing pixels, at least one microlens and at least one light blocking layer.

[0140] In a specific implementation, the at least one microlens can be disposed above the plurality of optical sensing pixels; the at least one light-blocking layer can be disposed between the at least one microlens and the plurality of optical sensing pixels, and each of the at least one light-blocking layer is provided with openings corresponding to the plurality of optical sensing pixels. The inclined light signals in multiple directions reflected from a finger above the display screen are converged by the at least one microlens and then transmitted to the plurality of optical sensing pixels through the openings provided in the at least one light-blocking layer. The inclined light signals are used to detect fingerprint information of the finger.

[0141] The multiple directions of the oblique light signals may be the directions of incident oblique light on the at least one microlens. For example, the at least one microlens may be considered as a whole, and in this case, the multiple directions may be the oblique light signals incident on the at least one microlens in four directions (front, back, left, and right) in a top view. The angles of the oblique light signals in these four directions relative to the plane of the display screen may be the same or different. The multiple directions may be directions relative to the plane of the display screen or directions relative to a three-dimensional space. The multiple directions may be mutually different or partially different.

[0142] The microlens can be any lens with a converging function, which is used to enlarge the field of view and increase the amount of light signal transmitted to the photosensitive pixel. The material of the microlens can be an organic material, such as resin.

[0143] The optical sensing pixel can be a photoelectric sensor for converting an optical signal into an electrical signal. Optionally, the optical sensing pixel can adopt a complementary metal oxide semiconductor (CMOS) device, a semiconductor device composed of a PN junction, which has a unidirectional conductive characteristic. Optionally, the optical sensing pixel has a light sensitivity greater than a first predetermined threshold for blue light, green light, red light or infrared light, and a quantum efficiency greater than a second predetermined threshold. For example, the first predetermined threshold can be 0.5v / lux-sec, and the second predetermined threshold can be 40%. That is to say, the photosensitive pixel has a higher light sensitivity and a higher quantum efficiency for blue light (wavelength of 460±30nm), green light (wavelength of 540±30nm), red light or infrared light (wavelength ≥610nm), so as to facilitate the detection of the corresponding light.

[0144] It should be understood that the embodiments of the present application do not limit the specific shapes of the microlenses and the optical sensing pixels. For example, each of the plurality of optical sensing pixels may be a polygonal pixel such as a quadrilateral or hexagonal pixel, or may be a pixel of another shape, such as a circular pixel, so that the plurality of optical sensing pixels have higher symmetry, higher sampling efficiency, equal distance between adjacent pixels, better angular resolution, and less aliasing effects.

[0145] It should also be understood that the above parameters of the photosensitive pixel may correspond to the light required for fingerprint detection. For example, if the light required for fingerprint detection is only light of one wavelength band, the above parameters of the photosensitive pixel only need to meet the requirements of the light of that wavelength band.

[0146] In the embodiment of the present application, the signals received by the plurality of optical sensing pixels are inclined light signals in multiple directions, that is, light signals in multiple directions with oblique incidence.

[0147] When the dry hand fingerprint has poor contact with the OLED screen, the contrast between the fingerprint ridges and the fingerprint valleys in the vertical direction of the fingerprint image is poor, and the image is blurred to the point where the fingerprint lines cannot be distinguished. This application uses a reasonable optical path design to allow the optical path to receive inclined light signals. While being able to better acquire normal finger fingerprints, it can also better detect dry finger fingerprint images. In normal life scenarios, such as after washing hands, getting up in the morning, dusting fingers, and low temperatures, fingers are usually dry and their stratum corneum is uneven. When pressed on the OLED screen, local areas of the fingers will have poor contact. The emergence of this situation causes the current optical fingerprint solution to be ineffective in dry hand fingerprint recognition. The beneficial effect of this application is to improve the dry hand fingerprint imaging effect and make the dry hand fingerprint image clearer.

[0148] In addition, the at least one microlens can perform non-straight light imaging (i.e., oblique light imaging) on ​​the oblique light signals in the multiple directions, which can shorten the thickness of the optical path design of the optical sensing pixel array (i.e., the at least one light-blocking layer), and ultimately effectively reduce the thickness of the fingerprint detection device. At the same time, by imaging the oblique light signals in multiple directions, the object-side numerical aperture of the optical system can be expanded, thereby improving the robustness and tolerance of the fingerprint detection device. The numerical aperture can be used to measure the angular range of light that can be collected by the at least one microlens. In other words, the multiple optical sensing pixels can also expand the field of view and field of view of the fingerprint detection unit by receiving light signals in multiple directions, thereby increasing the field of view and field of view of the fingerprint detection device. For example, the field of view of the fingerprint detection device can be expanded from 6x9mm2 to 7.5x10.5mm2, further improving the fingerprint recognition effect.

[0149] Furthermore, by disposing a plurality of optical sensing pixels below the at least one microlens, when the number of the at least one microlens is unequal to the number of the plurality of optical sensing pixels, the spatial period of the microlenses (i.e., the spacing between adjacent microlenses) and the spatial period of the optical sensing pixels (i.e., the spacing between adjacent optical sensing pixels) can be made unequal, thereby avoiding the appearance of moiré fringes in the fingerprint image and improving the fingerprint recognition effect. In particular, when the number of the at least one microlens is smaller than the number of the plurality of optical sensing pixels, the cost of the lenses can be reduced and the density of the plurality of optical sensing pixels can be increased, thereby reducing the size and cost of the fingerprint detection device.

[0150] At the same time, a single fingerprint detection unit can multiplex light signals in multiple directions (for example, a single microlens can multiplex light signals at four angles), and light beams with different object aperture angles can be split and imaged, effectively increasing the amount of light entering the fingerprint detection device, thereby reducing the exposure time of the optical sensing pixel.

[0151] Moreover, since the multiple optical sensing pixels can respectively receive oblique light signals from multiple directions, the multiple optical sensing pixels can be divided into multiple optical sensing pixel groups according to the direction of the oblique light signals. The multiple optical sensing pixel groups can be used to receive the oblique light signals in the multiple directions respectively, that is, each optical sensing pixel group can generate a fingerprint image based on the received oblique light signal, and thus the multiple optical sensing pixel groups can be used to generate multiple fingerprint images. In this case, the multiple fingerprint images can be superimposed to obtain a high-resolution fingerprint image, and then fingerprint recognition can be performed based on this high-resolution fingerprint image, which can improve the fingerprint recognition performance.

[0152] Based on the above analysis, it can be seen that the inclined light signals in multiple directions reflected from the finger above the display screen are converged by the at least one microlens and then transmitted to the multiple optical sensing pixels through the openings set in the at least one light-blocking layer. This not only reduces the exposure time of the multiple optical sensing pixels, as well as the thickness and cost of the fingerprint detection device, but also improves the robustness, tolerance, field of view and field of view of the fingerprint detection device, thereby improving the fingerprint recognition effect, especially the fingerprint recognition effect of dry fingers.

[0153] The fingerprint detection unit of the embodiment of the present application is described below with reference to the accompanying drawings.

[0154] In some embodiments of the present application, the number of the at least one microlens is equal to the number of the plurality of optical sensing pixels, wherein a microlens is disposed above each of the plurality of optical sensing pixels.

[0155] For example, in one implementation, the at least one microlens is a 2x2 microlens rectangular array, the multiple optical sensing pixels are a 2x2 optical sensing pixel rectangular array, and a microlens is disposed directly above each optical sensing pixel in the 2x2 optical sensing pixel rectangular array.

[0156] For another example, in one implementation, the at least one microlens is a 2x2 microlens rectangular array, the multiple optical sensing pixels are a 2x2 optical sensing pixel rectangular array, and a microlens is provided diagonally above each optical sensing pixel in the 2x2 optical sensing pixel rectangular array.

[0157] like Figure 5 As shown, the fingerprint detection unit 21 may include four optical sensing pixels 211 and four micro lenses 212 distributed in a rectangular array, wherein a micro lens 212 is arranged directly above each optical sensing pixel 211 .

[0158] At this time, if Figure 6 As shown, the fingerprint detection unit 21 may include a top light-blocking layer and a bottom light-blocking layer. The top light-blocking layer may include four openings 2141 corresponding to the four microlenses 212, and the bottom light-blocking layer may include four openings 213 corresponding to the four microlenses 212.

[0159] In one implementation, the 2x2 microlens rectangular array receives the inclined light signals in the multiple directions in a clockwise direction, and each microlens in the 2x2 microlens rectangular array converges the received inclined light signals to the optical sensing pixels under the adjacent microlens in the clockwise direction, or the 2x2 microlens rectangular array receives the inclined light signals in the multiple directions in a counterclockwise direction, and each microlens in the 2x2 microlens rectangular array converges the received inclined light signals to the optical sensing pixels under the adjacent microlens in the counterclockwise direction.

[0160] For example, Figure 7 As shown, the four micro lenses 212 can converge the inclined light signals in multiple directions to the four optical sensing pixels 211 along the following paths:

[0161] The microlens 212 at the upper right corner converges the received inclined light signal to the optical sensing pixel 211 at the upper left corner, the microlens 212 at the upper left corner converges the received inclined light signal to the optical sensing pixel 211 at the lower left corner, the microlens 212 at the lower left corner converges the received inclined light signal to the optical sensing pixel 211 at the lower right corner, and the microlens 212 at the lower right corner converges the received inclined light signal to the optical sensing pixel 211 at the upper right corner.

[0162] Therefore, when the fingerprint detection device includes multiple fingerprint detection units distributed in an array, multiple fingerprint images can be generated based on light signals received in multiple directions, thereby obtaining a high-resolution fingerprint image to improve the fingerprint recognition effect.

[0163] For example, the 4x4 fingerprint detection unit rectangular array may include: Figure 8 In the optical sensing pixel array shown, "1" represents an optical sensing pixel for receiving an oblique light signal in a first direction, "2" represents an optical sensing pixel for receiving an oblique light signal in a second direction, "3" represents an optical sensing pixel for receiving an oblique light signal in a third direction, and "4" represents an optical sensing pixel for receiving an oblique light signal in a fourth direction. In other words, the optical sensing pixels represented by "1," "2," "3," and "4" can each be used to generate a fingerprint image, for a total of four fingerprint images. These four fingerprint images can be combined into a high-resolution fingerprint image, thereby improving the recognition performance of the fingerprint detection device.

[0164] Combine Figure 7 For example, the first direction may be the direction of the inclined light signal received by the lower right microlens 212, the second direction may be the direction of the inclined light signal received by the upper right microlens 212, the third direction may be the direction of the inclined light signal received by the upper left microlens 212, and the fourth direction may be the direction of the inclined light signal received by the lower left microlens 212.

[0165] Figure 9 A side view of the fingerprint sensor located below the display.

[0166] like Figure 9 As shown, the fingerprint detection device may include microlenses 212 arranged in an array, a top light-blocking layer and a bottom light-blocking layer located below the microlenses 212, and optical sensing pixels arranged in an array below the bottom light-blocking layer, wherein for each microlens 212, the top light-blocking layer and the bottom light-blocking layer are respectively formed with corresponding openings 2141 and openings 213. The fingerprint detection device is disposed below a display screen 216.

[0167] Among them, each microlens 212 converges the received inclined light signal with a specific direction (the light signal shown by the solid line in the figure) to the corresponding optical sensing pixel through the corresponding opening 2141 and the opening 213, and transmits the received inclined light signal with a non-specific direction (the light signal shown by the dotted line in the figure) to the area in the light blocking layer except the opening 2141 and the opening 214 to avoid being received by other optical sensing pixels, thereby realizing the segmentation and imaging of the fingerprint image.

[0168] Figure 10 This is a schematic diagram of the optical path of optical signals inclined in two directions according to an embodiment of the present application.

[0169] Combine Figure 7 , assuming that a microlens 212 (e.g. Figure 7 The upper right corner micro lens 212 shown in FIG. 214b) receives the tilted light signal (ie, the second direction) in one direction through the corresponding opening 2141 and the opening 213. Figure 10 The light signal shown by the solid line in the middle) is focused to the corresponding optical sensing pixel (e.g. Figure 7 The optical sensing pixel 211 in the upper left corner is shown), and another micro lens 212 in the fingerprint detection unit (e.g. Figure 7 The micro lens 212 at the lower left corner as shown in the figure receives the tilted light signal ( Figure 10 The light signal shown by the solid line in the middle) is focused to the corresponding optical sensing pixel (e.g. Figure 7The optical sensing pixel 211 in the lower right corner is shown).

[0170] For example, Figure 10 As shown, the fingerprint recognition area of ​​a fingerprint detection device including multiple fingerprint detection units includes a first fingerprint recognition area and a second fingerprint recognition area. The fingerprint recognition area corresponding to the microlens 212 for converging the oblique light signal in the second direction is the first fingerprint recognition area, and the fingerprint recognition area corresponding to the microlens for converging the oblique light signal in the fourth direction is the second fingerprint recognition area. The first fingerprint recognition area is offset to the right by a first additional area relative to the array formed by the optical sensing pixels, and the second fingerprint recognition area is offset to the left by a second additional area relative to the array formed by the optical sensing pixels.

[0171] In other words, compared to a fingerprint detection device that only receives tilted light signals in one direction, the fingerprint detection device provided in the embodiment of the present application has a fingerprint recognition area that additionally includes the first and second increased areas, effectively increasing the visible area (i.e., field of view). Furthermore, the overlapping area of ​​the first and second fingerprint recognition areas can effectively improve the image resolution of the fingerprint image, thereby enhancing the fingerprint recognition effect.

[0172] It should be understood that Figure 7 The optical path design shown is only an example of this application and should not be understood as a display of this application.

[0173] In another implementation, the 2x2 microlens rectangular array receives the inclined light signals in the multiple directions along the diagonal direction of the 2x2 microlens rectangular array, and each microlens in the 2x2 microlens rectangular array converges the received inclined light signals to the optical sensing pixels under the adjacent microlens in the diagonal direction.

[0174] For example, Figure 11 and Figure 12 As shown, the four micro lenses 212 can converge the inclined light signals in multiple directions to the four optical sensing pixels 211 along the following paths:

[0175] The microlens 212 at the upper right corner converges the received inclined light signal to the optical sensing pixel 211 at the lower left corner, the microlens 212 at the lower left corner converges the received inclined light signal to the optical sensing pixel 211 at the upper right corner, the microlens 212 at the upper left corner converges the received inclined light signal to the optical sensing pixel 211 at the lower right corner, and the microlens 212 at the lower right corner converges the received inclined light signal to the optical sensing pixel 211 at the upper left corner.

[0176] Therefore, when the fingerprint detection device includes multiple fingerprint detection units distributed in an array, multiple fingerprint images can be generated based on light signals received in multiple directions, thereby obtaining a high-resolution fingerprint image to improve the fingerprint recognition effect.

[0177] Similarly, the 4x4 fingerprint detection unit rectangular array may include: Figure 8 In the optical sensing pixel array shown, "1" represents an optical sensing pixel for receiving an oblique light signal in a first direction, "2" represents an optical sensing pixel for receiving an oblique light signal in a second direction, "3" represents an optical sensing pixel for receiving an oblique light signal in a third direction, and "4" represents an optical sensing pixel for receiving an oblique light signal in a fourth direction. In other words, the optical sensing pixels represented by "1," "2," "3," and "4" can each be used to generate a fingerprint image, for a total of four fingerprint images. These four fingerprint images can be combined into a high-resolution fingerprint image, thereby improving the recognition performance of the fingerprint detection device.

[0178] Combine Figure 11 For example, the first direction may be the direction of the inclined light signal received by the lower left microlens 212, the second direction may be the direction of the inclined light signal received by the lower right microlens 212, the third direction may be the direction of the inclined light signal received by the upper right microlens 212, and the fourth direction may be the direction of the inclined light signal received by the upper left microlens 212.

[0179] It should be understood that in the embodiment of the present application, the fingerprint detection unit includes at least one light-blocking layer and a plurality of optical sensing pixels, wherein each light-blocking layer in the at least one light-blocking layer is provided with openings corresponding to the plurality of optical sensing pixels. For example, the at least one light-blocking layer may be a multi-layer light-blocking layer, and the top light-blocking layer of the multi-layer light-blocking layer may be provided with at least one opening corresponding to the plurality of optical sensing pixels. For example, the top light-blocking layer of the multi-layer light-blocking layer may be provided with an opening corresponding to the plurality of optical sensing pixels. For another example, the top light-blocking layer of the multi-layer light-blocking layer may be provided with a plurality of openings corresponding to the plurality of optical sensing pixels, respectively.

[0180] For example, Figure 12 As shown, the at least one light-blocking layer may include a top light-blocking layer and a bottom light-blocking layer, wherein the top light-blocking layer is provided with four openings 2141 corresponding to four optical sensing pixels respectively. The bottom light-blocking layer is provided with four openings 213 corresponding to four optical sensing pixels respectively.

[0181] For example, Figure 13As shown, the at least one light-blocking layer may include a top light-blocking layer and a bottom light-blocking layer, wherein the top light-blocking layer is provided with one opening 2142 corresponding to four optical sensing pixels and the bottom light-blocking layer is provided with four openings 213 corresponding to four optical sensing pixels respectively.

[0182] It should be understood that Figure 12 and Figure 13 The openings in the light-blocking layer are only Figure 11 The fingerprint detection unit shown is described as an example, and its implementation method is applicable to various embodiments of the present application, and the present application does not limit this.

[0183] For example, the at least one light-blocking layer may be a light-blocking layer having more than two layers.

[0184] It should also be understood that Figures 5 to 13 This is merely an example of disposing one microlens above each optical sensing pixel, and should not be construed as limiting the present application. For example, the fingerprint detection unit may also include other numbers or other arrangements of microlenses or optical sensing pixels.

[0185] For example, in another implementation, the at least one microlens is a plurality of rows of microlenses, and the plurality of optical sensing pixels are a plurality of rows of optical sensing pixels corresponding to the plurality of rows of microlenses, wherein each row of optical sensing pixels in the plurality of rows of optical sensing pixels is staggered below a corresponding row of microlenses.

[0186] Optionally, the multiple rows of microlenses may be multiple columns or multiple rows of microlenses.

[0187] In which, the at least one light-blocking layer may be provided with a corresponding optical path design so that the multiple rows of microlenses receive the inclined light signals in the multiple directions along the staggered directions of the multiple rows of optical sensing pixels, and each row of microlenses in the multiple rows of microlenses converges the received inclined light signals to the optical sensing pixels under the same row of microlenses or adjacent microlenses.

[0188] For example, Figure 14 As shown, the fingerprint detection unit 22 may include 4 columns of optical sensing pixels distributed in a rectangular array and 4 columns of microlenses corresponding to the 4 columns of optical sensing pixels, wherein each of the 4 columns of optical sensing pixels includes 6 optical sensing pixels 221, and each of the 4 columns of microlenses includes 6 microlenses 222, and one optical sensing pixel 221 is staggered below one microlens 222.

[0189] For example, the fingerprint detection unit 22 may include a top light-blocking layer and a bottom light-blocking layer. In this case, for each microlens 222, the top light-blocking layer and the bottom light-blocking layer may be provided with corresponding openings 2241 and 2231, respectively. Each microlens 222 in each row of microlenses in the multiple rows of microlenses can converge the received light signal to the optical sensing pixel 221 obliquely below the same microlens 222 through the corresponding openings 2241 and 2231.

[0190] Therefore, when the fingerprint detection device includes multiple fingerprint detection units distributed in an array, multiple fingerprint images can be generated based on light signals received in multiple directions, thereby obtaining a high-resolution fingerprint image to improve the fingerprint recognition effect.

[0191] For example, Figure 14 The fingerprint detection unit shown may include Figure 15 In the optical sensing pixel array shown, "1" represents an optical sensing pixel for receiving an oblique light signal in a first direction, and "2" represents an optical sensing pixel for receiving an oblique light signal in a second direction. In other words, the optical sensing pixels represented by "1" and "2" can each be used to generate a fingerprint image, resulting in a total of two fingerprint images. These two fingerprint images can be combined into a high-resolution fingerprint image, thereby improving the recognition performance of the fingerprint detection device.

[0192] Combine Figure 11 For example, based on the order from left to right, the first direction may be the direction of the inclined light signals received by the microlenses in the first and second columns of microlenses, and the second direction may be the direction of the inclined light signals received by the microlenses in the third and fourth columns.

[0193] Optionally, in one embodiment of the present application, the projection of each microlens in each row of microlenses in the multiple rows of microlenses on the plane where the display screen is located is circular, the projection of each optical sensing pixel in each row of optical sensing pixels in the multiple rows of optical sensing pixels on the plane where the display screen is located is rectangular, and the projection of the center of each optical sensing pixel in each row of optical sensing pixels in the multiple rows of optical sensing pixels on the plane where the display screen is located is offset by a preset distance along the misalignment direction of the multiple rows of optical sensing pixels relative to the projection of the center of the corresponding microlens on the plane where the display screen is located, and the preset distance is less than or equal to the side length of the rectangle or the diameter of the circle.

[0194] For example, Figure 14As shown, the staggered direction is the diagonal direction of each optical sensing pixel in each row of the multiple rows of optical sensing pixels, that is, each optical sensing pixel 221 in each row of the multiple rows of optical sensing pixels is offset by a preset distance along the diagonal direction of the same optical sensing pixel 221.

[0195] At this time, a corresponding opening 2241 and an opening 2231 may be provided above each optical sensing pixel 221 in each row of optical sensing pixels in the multiple rows of optical sensing pixels, that is, at least one light-blocking layer in the fingerprint detection unit 22 is provided with a corresponding opening above each optical sensing pixel 221.

[0196] It should be understood that the preset distance may also be an offset distance in the direction of the side length of the optical sensing pixel 221. For example, taking the two side lengths of the optical sensing pixel 221 as the X-axis direction and the Y-axis direction, the preset distance may include an offset distance along the X-axis direction and an offset distance along the Y-axis direction. For example, assuming that the side length of the optical sensing pixel is 12.5 mm and the diameter of the microlens is 11.5 mm, the offset distance along the X-axis direction may be 4 to 5 mm, and the offset distance along the Y-axis direction may be 4 to 5 mm. Of course, the above parameters are only examples and should not be understood as limitations on themselves. For example, the offset distance along the X-axis direction may not be equal to the offset distance along the Y-axis direction. For another example, the offset distance along the X-axis direction or the offset distance along the Y-axis direction may be greater than 5 mm or less than 4 mm.

[0197] certainly, Figure 14 This is merely an example of the offset of multiple rows of optical sensing pixels in the embodiment of the present application and should not be construed as a limitation to the present application.

[0198] For example, Figure 16 As shown, the staggered direction is the direction of the vertical side length of each optical sensing pixel in each row of the plurality of rows of optical sensing pixels. The vertical side length may be a direction parallel to the arrangement direction of the optical sensing pixels.

[0199] For example, the fingerprint detection unit 22 may include a top light-blocking layer and a bottom light-blocking layer. In this case, for each microlens 222, the top light-blocking layer and the bottom light-blocking layer may be provided with corresponding openings 2242 and 2232, respectively. Each microlens 222 in each row of microlenses in the multiple rows of microlenses can converge the received oblique light signal to the optical sensing pixel 221 directly below the adjacent microlens 222 through the corresponding openings 2242 and 2232. For example, the upper-left microlens 222 can converge the received oblique light signal to the optical sensing pixel 221 directly below the adjacent microlens 222 in the second row and first column.

[0200] At this time, the bottom light-blocking layer may be provided with its corresponding opening 2232 above each optical sensing pixel 221 in each row of optical sensing pixels in the multiple rows of optical sensing pixels, and the top light-blocking layer may be provided with its corresponding opening 2242 above the optical sensing pixel 221 adjacent to the same optical sensing pixel 221.

[0201] Of course, in other alternative embodiments, the staggered direction may be other directions, for example, the staggered direction is the direction of the horizontal side length of each optical sensing pixel in each row of the plurality of rows of optical sensing pixels. The horizontal side length may be a direction perpendicular to the arrangement direction of the optical sensing pixels.

[0202] In some other embodiments of the present application, the number of the at least one microlens is smaller than the number of the plurality of optical sensing pixels.

[0203] In one implementation, the at least one microlens is one microlens, the plurality of optical sensing pixels is a 2x2 optical sensing pixel rectangular array, and the one microlens is disposed directly above the 2x2 optical sensing pixel rectangular array.

[0204] For example, Figure 17 As shown, the fingerprint detection unit 23 may include a microlens 232 and four optical sensing pixels 231 distributed in a rectangular array.

[0205] In a specific implementation, at least one light-blocking layer in the fingerprint detection unit 23 may be provided with openings corresponding to the four optical sensing pixels 231 below the one microlens, so that the one microlens can receive the inclined light signals in the multiple directions along the diagonal direction of the 2x2 optical sensing pixel rectangular array. The one microlens can converge the inclined light signals in the multiple directions along the diagonal direction to the optical sensing pixels in the 2x2 optical sensing pixel rectangular array, so as to increase the amount of signal that each optical sensing pixel can receive, thereby improving the fingerprint recognition effect.

[0206] For example, Figure 18 and Figure 19As shown, the at least one light-blocking layer may include a top light-blocking layer and a bottom light-blocking layer. The top light-blocking layer is provided with openings 2341 corresponding to the four optical sensing pixels 231 below the one microlens 232, and the bottom light-blocking layer is provided with openings 232 corresponding to the four optical sensing pixels 231 below the one microlens 232. The one microlens 232 converges light signals received from multiple directions to the four optical sensing pixels 231 through the corresponding openings 2341 and openings 232.

[0207] Of course, the four small holes of the top light-blocking layer corresponding to the four optical sensing pixels 231 can also be merged into one large hole. Figure 20 and Figure 21 Opening 2342 is shown.

[0208] In another implementation, the one microlens is a 2x2 microlens rectangular array, the multiple optical sensing pixels are a 3x3 optical sensing pixel rectangular array, and a microlens is arranged directly above every 4 adjacent optical sensing pixels in the 3x3 rectangular array.

[0209] For example, Figure 22 As shown, the fingerprint detection unit 24 may include four micro lenses 242 distributed in a rectangular array and nine optical sensing pixels 241 distributed in a rectangular array.

[0210] In a specific implementation, at least one light-blocking layer in the fingerprint detection unit 24 may be respectively provided with openings corresponding to the optical sensing pixels 241 at the four corners of the 3x3 optical sensing pixel rectangular array, so that each microlens 242 in the 2x2 microlens rectangular array can converge the received inclined light signal to the optical sensing pixel 241 at the four corners of the 3x3 optical sensing pixel rectangular array that is closest to the same microlens 424.

[0211] For example, Figure 23 As shown, the at least one light-blocking layer may include a top light-blocking layer and a bottom light-blocking layer. The top light-blocking layer is provided with openings 244 corresponding to the optical sensing pixels 241 at the four corners, and the bottom light-blocking layer is provided with openings 243 corresponding to the optical sensing pixels 241 at the four corners. Thus, the four microlenses 242 can converge the inclined light signals from multiple directions to the optical sensing pixels 241 at the four corners through the corresponding openings 2341 and openings 243.

[0212] Since only the optical sensing pixels 241 at the four corners of the 3x3 optical sensing pixel rectangular array will receive the inclined light signals for detecting fingerprint information, in order to increase the utilization rate of the optical sensing pixels, in some embodiments of the present application, a fingerprint detection device including multiple fingerprint detection units 24 can be formed by an interlaced arrangement.

[0213] For example, Figure 24 As shown, the central fingerprint detection unit located in the middle position, the optical sensing pixel 241 between the upper left optical sensing pixel 241 and the upper right optical sensing pixel 241 thereof can be multiplexed as the optical sensing pixel 241 located at the lower left corner of another fingerprint detection unit, the optical sensing pixel 241 between the upper left optical sensing pixel 241 and the lower left optical sensing pixel 241 of the central fingerprint detection unit can be multiplexed as the optical sensing pixel 241 located at the lower right corner of another fingerprint detection unit, the optical sensing pixel 241 between the lower left optical sensing pixel 241 and the lower right optical sensing pixel 241 of the central fingerprint detection unit can be multiplexed as the optical sensing pixel 241 located at the upper right corner of another fingerprint detection unit, and the optical sensing pixel 241 between the lower right optical sensing pixel 241 and the upper right optical sensing pixel 241 of the central fingerprint detection unit can be multiplexed as the optical sensing pixel 241 located at the upper left corner of another fingerprint detection unit.

[0214] Thus, the fingerprint detection device may include Figure 25 The multiple optical sensing pixels shown in the figure, where "0" represents an optical sensing pixel that is not used to receive light signals, and "1", "2", "3", and "4" represent optical sensing pixels that receive signals from four different directions. In other words, the optical sensing pixels represented by "1", "2", "3", and "4" can each be used to generate a fingerprint image, that is, a total of four fingerprint images can be generated. These four fingerprint images can be used to merge into a high-resolution fingerprint image, thereby improving the recognition effect of the fingerprint detection device.

[0215] In another implementation, the at least one microlens is a 3x3 microlens rectangular array, the multiple optical sensing pixels are a 4x4 optical sensing pixel rectangular array, and a microlens is arranged directly above every 4 adjacent optical sensing pixels in the 4x4 optical sensing pixel rectangular array.

[0216] For example, Figure 26 As shown, the fingerprint detection unit 25 may include 9 micro lenses 252 distributed in a rectangular array and 16 optical sensing pixels 251 distributed in a rectangular array. Among the 16 optical sensing pixels 251, a micro lens 252 is provided directly above every 4 adjacent optical sensing pixels 251.

[0217] In a specific implementation, at least one light-blocking layer in the fingerprint detection unit 25 may be respectively provided with openings corresponding to the 16 optical sensing pixels 251, so that the central microlens in the 3x3 microlens rectangular array will respectively converge the received oblique light signals to the 4 optical sensing pixels below the central microlens, each of the microlenses at the 4 corners of the 3x3 microlens rectangular array will converge the received oblique light signals to the optical sensing pixels located at the corners of the 4x4 optical sensing pixel rectangular array below the same microlens, and each of the other microlenses in the 3x3 microlens rectangular array will converge the received oblique light signals to the two outer optical sensing pixels below the same microlens.

[0218] For example, Figure 27 As shown, the at least one light-blocking layer may include a top light-blocking layer and a bottom light-blocking layer. The top light-blocking layer is provided with openings 2541 corresponding to the 16 optical sensing pixels 251, and the bottom light-blocking layer is provided with openings 253 corresponding to the 16 optical sensing pixels 251. Thus, the nine microlenses 252 can converge the inclined light signals from multiple directions to the 16 optical sensing pixels 251 through the corresponding openings 2341 and openings 243.

[0219] Thus, the fingerprint detection device may include Figure 28 The multiple optical sensing pixels shown in the figure, where "1," "2," "3," and "4" represent optical sensing pixels for receiving signals from four different directions. In other words, the optical sensing pixels represented by "1," "2," "3," and "4" can each be used to generate a fingerprint image, for a total of four fingerprint images. These four fingerprint images can be combined into a high-resolution fingerprint image, thereby improving the recognition performance of the fingerprint detection device.

[0220] certainly, Figure 27 This is only an example of the present application and should not be considered as limiting the present application.

[0221] For example, Figure 29 As shown, the two small holes corresponding to the two optical sensing pixels 251 located between the two corners in the 4x4 optical sensing pixel rectangular array in the top light-blocking layer can be merged into one large hole, and the four small holes corresponding to the four adjacent optical sensing pixels 251 located at the center position in the 4x4 optical sensing pixel rectangular array in the top light-blocking layer can be merged into one large hole, so as to reduce the processing difficulty and increase the amount of converged light signals, thereby improving the fingerprint recognition effect of the fingerprint detection device.

[0222] In some embodiments of the present application, the fingerprint detection device includes a plurality of fingerprint detection units distributed in an array, each of the plurality of fingerprint detection units including a microlens and a 2x2 rectangular array of optical sensing pixels disposed below the microlens. In other words, the plurality of optical sensing pixels is a 2x2 rectangular array of optical sensing pixels, with a microlens disposed directly above the 2x2 rectangular array of optical sensing pixels. Each microlens converges received oblique light signals from multiple directions to the optical sensing pixels beneath the adjacent plurality of microlenses.

[0223] Figure 30 It is a schematic structural diagram of the fingerprint detection device of an embodiment of the present application.

[0224] like Figure 30 As shown, the fingerprint detection device may include a microlens array 310, at least one light-blocking layer, and an optical sensing pixel array 340. The microlens array 310 may be arranged below the display screen of an electronic device, the at least one light-blocking layer may be arranged below the microlens array 310, and the optical sensing pixel array 340 may be arranged below the at least one light-blocking layer. It should be noted that the fingerprint detection device may be applicable to Figures 1 to 4 The electronic device 10 shown, or the fingerprint detection device can be Figures 1 to 4 The optical fingerprint module 130 shown. The micro lens array 310 and the at least one light blocking layer can be Figure 3 or Figure 4 The optical component 132 includes a light guide structure, and the optical sensing pixel array 340 can be Figures 1 to 4 The sensing array 133 shown has a plurality of optical sensing units 131 (also referred to as optical sensing pixels, photosensitive pixels, pixel units, etc.), which will not be described again here to avoid repetition.

[0225] Please continue to see Figure 30 The microlens array 310 includes a plurality of microlenses. For example, the microlens array 310 may include a first microlens 311, a second microlens 312, and a third microlens 313. The at least one light-blocking layer may include a plurality of light-blocking layers. For example, the at least one light-blocking layer may include a first light-blocking layer 320 and a second light-blocking layer 330. The optical sensing pixel array 340 may include a plurality of optical sensing pixels. For example, the optical sensing pixel array may include a first optical sensing pixel 341, a second optical sensing pixel 342, a third optical sensing pixel 343, a fourth optical sensing pixel 344, a fifth optical sensing pixel 345, and a sixth optical sensing pixel 346.

[0226] The at least one light blocking layer is formed with a plurality of light guiding channels corresponding to each microlens in the microlens array 310 , and the bottoms of the plurality of light guiding channels corresponding to each microlens extend to the bottom of the adjacent plurality of microlenses.

[0227] Please continue to see Figure 30 The first light-blocking layer 320 and the second light-blocking layer 330 are respectively provided with at least one opening corresponding to each microlens of the plurality of microlenses (i.e., the first microlens 311, the second microlens 312, and the third microlens 313). For example, the first light-blocking layer 320 is provided with a first opening 321 and a second opening 322 corresponding to the first microlens 311, the first light-blocking layer 320 is further provided with a second opening 322 and a third opening 323 corresponding to the second microlens 312, and the first light-blocking layer 320 is provided with a third opening 323 and a fourth opening 324 corresponding to the third microlens 313. Similarly, the second light-blocking layer 330 is provided with a fifth opening 331 and a sixth opening 332 corresponding to the first microlens 311, and the second light-blocking layer 330 is also provided with a seventh opening 333 and an eighth opening 334 corresponding to the second microlens 312, and the second light-blocking layer 330 is provided with a ninth opening 335 and a tenth opening 336 corresponding to the third microlens 313.

[0228] Taking the second microlens 312 as an example, the multiple light guiding channels corresponding to the second microlens 312 may include a light guiding channel formed by the second opening 322 and the sixth opening 332, and a light guiding channel formed by the third opening 323 and the ninth opening 335. The light guiding channel formed by the second opening 322 and the sixth opening 332 extends below the first microlens 311, and the light guiding channel formed by the third opening 323 and the ninth opening 335 extends below the third microlens 313.

[0229] Wherein, an optical sensing pixel may be provided below each of the plurality of light guiding channels corresponding to each microlens in the microlens array 310 .

[0230] Taking the second microlens 312 as an example, a second optical sensing pixel 342 is disposed below the light guide channel formed by the second opening 322 and the sixth opening 332 , and a fifth optical sensing pixel 345 is disposed below the light guide channel formed by the third opening 323 and the ninth opening 335 .

[0231] In other words, a plurality of optical sensing pixels are disposed below each microlens in the microlens array 310. The plurality of optical sensing pixels disposed below each microlens are respectively configured to receive light signals converged by adjacent microlenses and transmitted through corresponding light guide channels, and the light signals are used to detect fingerprint information of a finger.

[0232] Taking the second microlens 312 as an example, a third optical sensing pixel 343 and a fourth optical sensing pixel 344 can be arranged below the second microlens 312, wherein the third optical sensing pixel 343 can be used to receive the inclined light signal converged by the first microlens 311 and transmitted through the light guiding channel formed by the second opening 322 and the seventh opening 333, and the fourth optical sensing pixel 344 can be used to receive the inclined light signal converged by the third microlens 313 and transmitted through the light guiding channel formed by the third opening 323 and the eighth opening 334.

[0233] Furthermore, the distribution of the multiple optical sensing pixels under each microlens in the microlens array 310 may be polygonal. For example, the polygon includes, but is not limited to, a rectangle or a diamond. For another example, the distribution of the multiple optical sensing pixels under each microlens in the microlens array 310 may be circular or elliptical.

[0234] Since the microlenses in the microlens array are distributed in an array, when the multiple optical sensing pixels under each microlens are distributed in a polygonal shape, the correspondence between the microlens array and the optical sensing array can be effectively simplified, thereby simplifying the structural design of the fingerprint detection device.

[0235] By rationally designing the multiple light-guiding channels corresponding to each microlens, the optical sensing pixel array 340 can receive tilted light signals from multiple directions and converge these tilted light signals through a single microlens, thus resolving the issue of long exposure time associated with a single object-space telecentric microlens array solution. In other words, the fingerprint detection device not only addresses the poor recognition performance of dry fingers with vertical light signals and the long exposure time associated with a single object-space telecentric microlens array solution, but also addresses issues such as excessive thickness, poor tolerance, and oversized dimensions of the fingerprint detection device.

[0236] Please continue to see Figure 30 The fingerprint detection device may further include a transparent medium layer 350 .

[0237] The transparent dielectric layer 350 may be disposed in at least one of the following locations: between the microlens array 310 and the at least one light-blocking layer; between the at least one light-blocking layer; and between the at least one light-blocking layer and the optical sensing pixel array 340. For example, the transparent dielectric layer 350 may include a first dielectric layer 351 between the microlens array 310 and the at least one light-blocking layer (i.e., the first light-blocking layer 320) and a second dielectric layer 352 between the first light-blocking layer 320 and the second light-blocking layer 330.

[0238] The material of the transparent medium layer 350 can be any transparent material that is transparent to light, such as glass, or can be made of air or vacuum, which is not specifically limited in this application.

[0239] The following describes in detail the design of the multiple light guiding channels corresponding to each microlens.

[0240] In some embodiments of the present application, the multiple light-guiding channels corresponding to each microlens in the microlens array 310 can be centrally symmetrically distributed along the optical axis of the same microlens. By centrally symmetrically arranging the multiple light-guiding channels corresponding to each microlens, the process complexity of the fingerprint detection device can be reduced.

[0241] Please continue to see Figure 30 Taking the second microlens 312 as an example, the light guiding channel formed by the second opening 322 and the sixth opening 332 corresponding to the second microlens 312 and the light guiding channel formed by the third opening 323 and the ninth opening 335 corresponding to the second microlens 312 are symmetrical along the optical axis direction of the second microlens 312.

[0242] In some embodiments of the present application, each of the multiple light-guiding channels corresponding to each microlens in the microlens array 310 can form a preset angle with the first plane, so that the multiple optical sensing pixels disposed below each microlens are respectively configured to receive light signals converged by the adjacent multiple microlenses and transmitted through the corresponding light-guiding channel, wherein the first plane is a plane parallel to the display screen. Optionally, the preset angle can ensure that the bottom ends of the multiple light-guiding channels corresponding to each microlens extend below the multiple microlenses adjacent to the same microlens.

[0243] Please continue to see Figure 30 Taking the second microlens 312 as an example, the plane where the optical sensing pixel array 340 is located is parallel to the first plane. The light guide channel formed by the second opening 322 and the sixth opening 332 forms a first angle with the plane where the optical sensing pixel array 340 is located. The light guide channel formed by the third opening 323 and the ninth opening 335 forms a second angle with the plane where the optical sensing pixel array 340 is located. The first angle is equal to the second angle. Of course, in other alternative embodiments, the first angle may not be equal to the second angle, and this embodiment of the present application is not limited to this.

[0244] It should be noted that the preset angle can be the angle between the axis of the light-guiding channel and the first plane, or the angle between any straight line passing through the light-guiding channel and the first plane; in addition, the range of the preset angle can be any range between 0 degrees and 90 degrees, for example, the range of the preset angle can be 15 degrees to 60 degrees, or 10 degrees to 70 degrees, and this application does not make any specific restrictions on this.

[0245] In some embodiments of the present application, the projections of the multiple light-guiding channels corresponding to each microlens in the microlens array 310 on the first plane can be centrally symmetrically distributed relative to the projection of the optical axis of the same microlens on the first plane, so as to ensure that each optical sensing pixel in the optical sensing pixel array can receive sufficient light signals, thereby improving the resolution of the fingerprint image and the fingerprint recognition effect.

[0246] Figure 31 yes Figure 30 A schematic top view of a fingerprint detection unit in the fingerprint detection device shown.

[0247] like Figure 31 As shown, the fingerprint detection unit 30 may include the second microlens 312 and a 2×2 rectangular array of optical sensing pixels disposed below the second microlens 312 .

[0248] The four light-guiding channels corresponding to the second microlens 312 are symmetrically distributed along the center of projection of the optical axis of the second microlens 312 onto the first plane, on the end surface near the optical sensing pixel array 340. In other words, the four openings on the first light-blocking layer 320 corresponding to the second microlens 312 are symmetrical along the optical axis of the second microlens 312, and the four openings on the second light-blocking layer 330 corresponding to the second microlens 312 are symmetrical along the optical axis of the second microlens 312. Optionally, the openings on the first light-blocking layer 320 and / or the openings on the second light-blocking layer 330 are elliptical openings.

[0249] It should be noted that, in the embodiment of the present application, the second microlens 312 can cover part or all of the photosensitive area (PD area, AA) of the third optical sensing pixel 343. Preferably, the second microlens 312 can cover the area in the photosensitive area (AA) of the third optical sensing pixel 343 that can be irradiated by the inclined light signal converged by the first microlens 311 and transmitted through the light guiding channel formed by the second opening 322 and the seventh opening 333, so as to ensure that the microlenses and optical sensing pixels in the fingerprint detection device can be arranged in an array, thereby simplifying the preparation process of the fingerprint detection device.

[0250] Figure 32 yes Figure 30 A schematic top view of the fingerprint detection device shown.

[0251] like Figure 33 As shown, the fingerprint detection device includes a 3x3 micro-lens rectangular array, wherein the micro-lens located at the lower left corner of the 3x3 micro-lens rectangular array is Figure 30 The first microlens 311, the microlens located in the center of the 3x3 microlens rectangular array is Figure 30 The second microlens 312 shown, and the microlens 313 located at the upper right corner of the 3x3 microlens rectangular array are Figure 30 The third microlens 313 is shown.

[0252] In other words, each microlens in the fingerprint detection device is used to transmit the received inclined light signals in multiple directions to the optical sensing pixels arranged below the adjacent microlenses in the diagonal direction of the 3x3 microlens rectangular array centered on the same microlens.

[0253] It should be understood that the embodiment of the present application does not specifically limit the arrangement and size of the optical sensing pixel array.

[0254] For example, Figure 33 As shown, the fingerprint detection unit 30 may include the second microlens 312 and four optical sensing pixels arranged in a diamond pattern below the second microlens 312. The second microlens 312 completely covers the four optical sensing pixels arranged in a diamond pattern. Optionally, the opening on the first light-blocking layer 320 and / or the opening on the second light-blocking layer 330 is a circular opening.

[0255] At this time, each microlens in the fingerprint detection device can be used to transmit the received inclined light signals in multiple directions to the optical sensing pixels arranged below the adjacent microlenses along the side length direction of the 3x3 microlens rectangular array centered on the same microlens.

[0256] Of course, in other alternative embodiments, the openings on the first light-blocking layer 320 and / or the openings on the second light-blocking layer 330 are polygonal openings such as quadrilateral openings.

[0257] Figure 34 It is a schematic structural diagram of the fingerprint detection system 40 according to an embodiment of the present application.

[0258] like Figure 34 As shown, the fingerprint detection system 40 may include a lens 402 , a prism 404 located below the lens 402 , and an optical sensing pixel array 406 located below the prism 404 .

[0259] Among them, the lens 402 is used to converge the light signals 401 received in multiple directions to the prism 404, and the prism 404 is used to image the light signals 403 converged by the lens 402 to the optical sensing pixel array 406 through reflection and / or refraction, so that the optical sensing pixel array 406 can output the generated analog image signal 407 capable of representing multiple fingerprint images to the subsequent module, so that the subsequent module can perform signal processing and fingerprint recognition.

[0260] It should be noted that the prism 404 can convert an incident light signal into multiple light signals through reflection and / or refraction and transmit them to the optical sensing pixel array 406. In other words, the prism 404 can form multiple images of an object through reflection and / or refraction.

[0261] Please continue to see Figure 34 The prism 404 may be a heptagonal prism or a prism of other shapes, which is not specifically limited in this application.

[0262] Figure 35 It is a schematic structural diagram of another fingerprint detection system according to an embodiment of the present application.

[0263] like Figure 35 As shown, the fingerprint detection system 50 may include a lens 502 and an optical sensing pixel array 506 located below the lens 502.

[0264] The optical sensing pixel array 506 may include multiple optical sensing units, which are arranged parallel to or at a preset angle along the plane of the display screen. For example, the multiple optical sensing units are arranged at different angles along the plane of the display screen. The lens 502 is used to converge the received light signals 501 from multiple directions to the optical sensing pixel array 506. The optical sensing pixel array 506 forms multiple images of an object through the multiple optical sensing units arranged at different angles, and then outputs the generated analog image signals 505 capable of representing multiple fingerprint images to subsequent modules for signal processing and fingerprint recognition.

[0265] It should be understood that Figures 5 to 35 This is merely an example of a fingerprint detection unit of the present application and should not be construed as limiting the present application. Any fingerprint detection unit, fingerprint detection device, or fingerprint detection system that can perform fingerprint recognition based on multi-directional optical signals based on the inventive concept of the present application falls within the scope of protection of the present application.

[0266] For example, in other alternative embodiments, the first light-blocking layer 320 may also be provided with multiple openings corresponding to each microlens, wherein the multiple light-guiding channels corresponding to each microlens respectively pass through the multiple openings in the first light-blocking layer 320 corresponding to the same microlens.

[0267] For another example, each microlens in the microlens array 310 can be filled in a circular shape or a square shape. The material of each microlens in the microlens array 310 can be plastic or glass. The production process of each microlens in the microlens array 310 can be implemented by a micro-nano processing process or a compression molding process.

[0268] For example, the above-mentioned figures illustrate the light path design by taking the example that the at least one light-blocking layer includes a top light-blocking layer and a bottom light-blocking layer, but the present application is not limited thereto.

[0269] For example, in one embodiment of the present application, the fingerprint detection device includes at least one light-blocking layer which is a multi-layer light-blocking layer, and the bottom light-blocking layer in the multi-layer light-blocking layer is provided with a plurality of openings corresponding to the plurality of optical sensing pixels, so that the at least one microlens can converge the inclined light signals in the plurality of directions to the plurality of optical sensing pixels through the plurality of openings.

[0270] In a specific implementation, the apertures corresponding to the same pixel in the multi-layer light-blocking layer decrease in diameter from top to bottom. The aperture of the aperture in the upper light-blocking layer is set larger than the aperture of the aperture in the lower light-blocking layer, so that the multi-layer light-blocking layer can guide more light signals (within a certain angle range) to the corresponding photosensitive pixel.

[0271] For another example, in other embodiments of the present application, the at least one light-blocking layer may be a light-blocking layer, and the light-blocking layer is provided with a plurality of inclined holes corresponding to the plurality of optical sensing pixels, so that the at least one microlens converges the inclined light signals in the plurality of directions to the plurality of optical sensing pixels respectively through the plurality of openings.

[0272] In a specific implementation, the thickness of the light-blocking layer may be greater than or equal to a preset thickness, so that the multiple inclined holes are respectively used to transmit inclined light signals in the multiple directions, thereby avoiding crosstalk between the inclined light signals transmitted by the multiple inclined holes.

[0273] It should be understood that the inclination angle of each of the multiple inclined holes can be determined according to the optical path design requirements. The multiple inclined holes can be multiple inclined holes with different inclination angles, or can be inclined holes with partially or completely the same inclination angles.

[0274] In one embodiment of the present application, each of the at least one light-blocking layer has a transmittance of less than 20% for light in a specific wavelength band (e.g., visible light or a wavelength band above 610 nm) to prevent the corresponding light from passing through. For example, each of the at least one light-blocking layer may be a metal layer, and accordingly, the opening provided in the light-blocking layer may be a through-hole formed in the metal layer.

[0275] For example, the opening is a cylindrical through hole. In one embodiment of the present application, the aperture of the opening is greater than 100 nm, so as to transmit the required light for imaging. The aperture of the opening is also smaller than a predetermined value to ensure that the light-blocking layer can block unnecessary light. That is to say, the parameters of the opening are set so that the light signal required for imaging is transmitted to the optical sensing pixel as much as possible, while the unnecessary light is blocked as much as possible. For example, the parameters of the opening can be set so that the light signal incident at a specific angle (for example, 35 degrees) is transmitted to the corresponding optical sensing pixel as much as possible, while other light signals are blocked as much as possible.

[0276] In some embodiments of the present application, the fingerprint detection device may further include a transparent medium layer.

[0277] The lens dielectric layer is used to connect the at least one microlens, the at least one light-blocking layer, and the plurality of optical sensing pixels. The transparent dielectric layer can transmit optical signals of the target wavelength band (i.e., optical signals of the wavelength band required for fingerprint detection). For example, the transparent dielectric layer can be made of oxides or nitrides. Optionally, the transparent dielectric layer can include multiple layers to respectively achieve functions such as protection, transition, and buffering. For example, a transition layer can be provided between the inorganic layer and the organic layer to achieve a close connection; a protective layer can be provided on the easily oxidized layer to achieve protection.

[0278] In some embodiments of the present application, the fingerprint detection device may further include a filter layer.

[0279] Wherein, the filter layer is arranged in the optical path between the at least one microlens and the multiple optical sensing pixels or above the microlens, and is used to filter out light signals in non-target bands to transmit light signals in the target band. Optionally, the transmittance of the filter layer to light in the target band is ≥80%, and the cutoff rate to light in the non-target band is ≥80%. Optionally, the filter layer can be an independently formed filter layer. For example, the filter layer can be a filter layer formed using blue crystal or blue glass as a carrier. Optionally, the filter layer can be a coating formed on the surface of any layer in the optical path. For example, the filter layer can be formed by coating on the surface of the photosensitive pixel, the surface of any layer in the transparent medium layer, or the lower surface of the microlens.

[0280] Figure 36FIG. 6 is a schematic structural diagram of a fingerprint detection system 60 according to an embodiment of the present application.

[0281] like Figure 36 As shown, light (Light) 603 reflected by a sampling entity (Object) 601 above a display screen 602 is converged to a fingerprint detection device 606 through a lens (Lens) or a microlens (Microlens) 604. The fingerprint detection device 606 receives a light signal 605 converged by the lens or the microlens 604 to generate and output an analog image signal 607 to an analog-to-digital converter 608. The analog-to-digital converter 608 generates a digital image signal 609 based on the received analog image signal 607 and outputs the digital image signal 609 to an image processor 610. The image processor 610 generates a compressed image signal 611 and stores the compressed image signal 611 in a memory 612, so that an electronic device equipped with the fingerprint detection system 60 can obtain the compressed image signal 611 from the memory 612 and perform fingerprint registration or fingerprint recognition based on the compressed image signal 611.

[0282] It should be noted that optical fingerprint recognition technology carries the risk of misidentification. For example, a fake fingerprint containing partial fingerprint information is placed at the sampling location, and light and shadow imaging is used to generate a fingerprint image to be matched. When the fingerprint image successfully matches the template in the library, the "unlock" operation is completed.

[0283] Since there are many ways to obtain personal fingerprint information, and 2D fingerprint image molds have clear fingerprint features and low production costs, the fingerprint recognition solution based on 2D fingerprint images has great security risks.

[0284] An embodiment of the present application provides a method for identifying fingerprints. By identifying whether a sampling entity placed above a display screen is a 2D entity or a 3D entity, the identification of the 2D entity is rejected from the source of the identification process, which can effectively reduce the risk of misidentification.

[0285] Figure 37 FIG is a schematic flow chart of a fingerprint identification method 70 according to an embodiment of the present application. It should be understood that the method 70 may be Figures 1 to 4 The electronic device with the fingerprint recognition module shown is executed to realize under-screen fingerprint recognition. The method 70 can also be executed only by a fingerprint detection device including a detection unit, and this application does not make specific limitations on this. For ease of explanation, the following description is taken as an example of a fingerprint detection device (also referred to as a fingerprint recognition device, fingerprint detection system or fingerprint recognition system).

[0286] like Figure 37 As shown, the method 70 may include some or all of the following:

[0287] S710: The fingerprint detection device obtains light signals in multiple directions reflected by a sampling entity above the display screen.

[0288] S720: The fingerprint detection device generates a plurality of two-dimensional (2D) fingerprint images based on the light signals in the plurality of directions.

[0289] S730: The fingerprint detection device determines whether the sampled entity is a three-dimensional (3D) entity based on the multiple 2D fingerprint images.

[0290] S740: If the sampled entity is a 3D entity, the fingerprint detection device performs fingerprint recognition based on at least one 2D fingerprint image among the multiple 2D fingerprint images.

[0291] In short, after the fingerprint detection device acquires the multiple 2D fingerprint images through light signals from multiple directions, it can determine whether the sampled entity is a 2D entity or a 3D entity, and perform subsequent fingerprint recognition when the sampled entity is a 3D entity.

[0292] In other words, the optical signals in multiple directions effectively distinguish between 2D entities and 3D entities, thereby improving the security of fingerprint recognition.

[0293] It should be understood that the specific parameters of the optical signals in multiple directions involved in the embodiments of the present application are not limited.

[0294] For example, the light signals in the multiple directions include light signals perpendicular to the display screen and light signals tilted relative to the display screen; or the light signals in the multiple directions include light signals tilted relative to the display screen. For example, the light signals in the multiple directions include only light signals tilted relative to the display screen.

[0295] For another example, the angles between the light signals in some or all of the multiple directions and the display screen may be the same or different.

[0296] Figure 38 It is a schematic structural diagram of the fingerprint detection system of an embodiment of the present application. Figures 39 to 41 They are Figure 38 The fingerprint detection device in the fingerprint detection system shown can obtain a fingerprint image.

[0297] like Figure 38 As shown, the fingerprint detection device 804 receives the optical signal 801 and the optical signal 802 reflected by the sampling entity.

[0298] When the sampling entity is a 2D entity, the fingerprint detection device 804 can obtain a 2D fingerprint image, wherein the 2D fingerprint image may include image lines for representing the ridge lines of the finger. Since the 2D entity is a planar entity, the width of the image lines in the 2D fingerprint image obtained by the fingerprint detection device 804 is proportional to the width of the ridge lines in the 2D entity.

[0299] It should be understood that the 2D fingerprint image acquired by the fingerprint detection device 804 may include at least one image line representing a fingerprint ridge, and each of the at least one image line may include at least one line unit. Each of the at least one line unit may be a pixel value formed by one or more optical sensing pixels in the fingerprint detection device 804. The width of each of the at least one line unit may be a length in a direction perpendicular to the image line in which the same line unit is located.

[0300] like Figure 39 As shown, the fingerprint detection device 804 can form a 2D fingerprint image 805 after receiving the light signal 802 passing through the display screen 803, and after receiving the light signal 801 passing through the display screen 803, wherein the width of each pattern unit of the image pattern 8051 of the 2D fingerprint image 805 is equal.

[0301] If the sampled entity is a 3D entity, the fingerprint detection device 804 can obtain a 2D fingerprint image after receiving the light signal that passes through the display screen 803. The 2D fingerprint image may include image patterns representing ridge lines. Since the 3D entity is a three-dimensional entity, if the light signal received by the fingerprint detection device 804 is an oblique light signal reflected by the 3D entity, the light signal reflected by the side of the ridge of the 3D entity will also form the image patterns of the 2D fingerprint image. Therefore, if the sampled entity is a 3D entity, the width of the image patterns in the 2D fingerprint image is not proportional to the width of the ridge lines of the 3D entity pressed on the display screen 803.

[0302] like Figure 40As shown, after receiving light signal 802 passing through display screen 803, fingerprint detection device 804 obtains 2D fingerprint image 806. The width of the texture units in image texture 8061 of 2D fingerprint image 806 that are parallel to light signal 802 can be equal to a fixed value, and the width of the texture units in image texture 8061 of 2D fingerprint image 806 that intersect with light signal 802 can be greater than the fixed value. Alternatively, the fixed value can be the product of the scaling ratio of fingerprint detection device 804 and the width of the ridge texture of the 3D entity pressed on display screen 803.

[0303] In other words, the width of the line units in the image lines 8061 of the 2D fingerprint image 806 that are parallel to the light signal 802 may be equal to the width of the line units in the image lines of the 2D fingerprint image 805. The width of the line units in the image lines 8061 of the 2D fingerprint image 806 that intersect with the light signal 802 may be greater than the width of the line units in the image lines of the 2D fingerprint image 805.

[0304] Similarly, if Figure 41 As shown, after receiving the light signal 801 passing through the display screen 803, the fingerprint detection device 804 obtains a 2D fingerprint image 807. The width of the line units in the image lines 8071 of the 2D fingerprint image 807 that are parallel to the light signal 802 may be smaller than the width of the line units in the image lines 8071 of the 2D fingerprint image 807 that intersect with the light signal 802.

[0305] Based on the above analysis, in some embodiments of the present application, the fingerprint detection device may first determine whether the multiple 2D fingerprint images are identical; and then determine whether the sampling entity is a 3D entity based on whether the multiple 2D fingerprint images are identical.

[0306] For example, if the multiple 2D fingerprint images are completely identical, the sampled entity is determined to be a 2D entity; if the multiple 2D fingerprint images are different, the sampled entity is determined to be a 3D entity.

[0307] It should be understood that the multiple 2D fingerprint images being different may mean that the multiple 2D fingerprint images are completely different, or the multiple 2D fingerprint images are partially different.

[0308] For example, if the curvatures of the lines of the same image in the multiple 2D fingerprint images are different, the fingerprint detection device can determine that the multiple 2D fingerprint images are different; and / or if the widths of the lines of the same image in the multiple 2D fingerprint images are different, the fingerprint detection device can determine that the multiple 2D fingerprint images are different.

[0309] For another example, if the curvatures of the multiple 2D fingerprint images for the same texture unit are different, the fingerprint detection device can determine that the multiple 2D fingerprint images are different; and / or if the widths of the multiple 2D fingerprint images for the same texture unit are different, the fingerprint detection device can determine that the multiple 2D fingerprint images are different.

[0310] For another example, if the multiple 2D fingerprint images do not completely overlap, the fingerprint detection device determines that the multiple fingerprint images are not the same.

[0311] As an example of S740, the fingerprint detection device may first generate a target 2D fingerprint image based on the multiple 2D fingerprint images, wherein the image texture of the target 2D fingerprint image includes the image textures of the multiple 2D fingerprint images overlapping with each other; and then the fingerprint detection device may perform fingerprint recognition based on the target 2D fingerprint image.

[0312] For example, if the target 2D fingerprint image and the pre-stored 2D fingerprint image match successfully, the fingerprint detection device determines that the fingerprint recognition is successful; and / or if the target 2D fingerprint image and the pre-stored 2D fingerprint image fail to match, the fingerprint detection device determines that the fingerprint recognition fails.

[0313] In other words, after determining that the sampled entity is a 3D entity, the fingerprint detection device can directly perform fingerprint recognition based on the 2D fingerprint image. In this case, a 2D fingerprint image template for matching can be pre-stored in the memory of the fingerprint detection device or the memory of the electronic device to which the fingerprint detection device belongs, so as to facilitate matching with the target 2D fingerprint image. The 2D fingerprint image template can be a fingerprint template obtained through the fingerprint registration process.

[0314] It should be understood that the target 2D fingerprint image can be a fingerprint image obtained by the fingerprint detection device based on the multiple 2D fingerprint images obtained through correction calculation. For example, the target 2D fingerprint image can be a fingerprint image formed by the overlapping parts of the multiple 2D fingerprint images. For example, Figure 42 The 2D fingerprint image 808 shown may include at least one image pattern 8081. Of course, the target 2D fingerprint image may also be a fingerprint image directly formed by the fingerprint detection device based on the received light signal reflected by the sampling entity and perpendicular to the display screen.

[0315] As another example of S740, the fingerprint detection device may first generate a target 3D fingerprint image based on the target 2D fingerprint image; and then perform fingerprint recognition based on the target 3D fingerprint image.

[0316] For example, if the target 3D fingerprint image and the pre-stored 3D fingerprint image match successfully, the fingerprint detection device determines that the fingerprint recognition is successful; and / or if the target 3D fingerprint image and the pre-stored 3D fingerprint image fail to match, the fingerprint detection device determines that the fingerprint recognition fails.

[0317] In other words, after determining that the sampled entity is a 3D entity, the fingerprint detection device can form a 3D fingerprint image based on the 2D fingerprint image, and then perform fingerprint recognition based on the 3D fingerprint image. In this case, a 3D fingerprint image template for matching can be pre-stored in the memory of the fingerprint detection device or the memory of the electronic device to which the fingerprint detection device belongs, so as to facilitate matching with the target 3D fingerprint image. The 3D fingerprint image template can be a fingerprint template obtained through the fingerprint registration process.

[0318] It should be understood that the embodiments of the present application may also perform fingerprint recognition in other matching ways, and this application does not make specific limitations on this.

[0319] For example, the curved surface of the target 3D fingerprint image is projected onto a fixed plane, that is, the 3D fingerprint image obtained under different pressing strengths is normalized into a 2D fingerprint image, and then matched with the 2D fingerprint image template based on the 2D fingerprint image to reduce the mismatching rate and thus improve the user experience.

[0320] For another example, the plane of the 2D fingerprint image template is projected onto a fixed curved surface to form a 3D fingerprint image template, and then the 3D fingerprint image template is matched with the target 3D fingerprint image to improve security and thus improve user experience.

[0321] The following describes how to implement the target 3D fingerprint image in an embodiment of the present application.

[0322] In some embodiments of the present application, first, the fingerprint detection device determines the height of each texture unit on each image texture in the target 2D fingerprint image based on the target 2D fingerprint image and the first 2D fingerprint image among the multiple 2D fingerprint images; then, the fingerprint detection device generates the target 3D fingerprint image based on the height of each texture unit on each image texture in the target 2D fingerprint image.

[0323] The first 2D fingerprint image may be a fingerprint image formed by the fingerprint detection device based on a light signal received and reflected by a sampling entity at an angle relative to the display screen, and the target 2D fingerprint image may be a fingerprint image obtained by the fingerprint detection device after correction calculation based on the multiple acquired 2D fingerprint images. Of course, the target 2D fingerprint image may also be a fingerprint image formed by the fingerprint detection device based on a light signal received and reflected by a sampling entity at a right angle relative to the display screen.

[0324] In conjunction with the accompanying drawings, the first 2D fingerprint image can be as follows Figure 40 2D fingerprint image 806 as shown or as Figure 41 The target 2D fingerprint image 807 may be as shown in FIG. Figure 39 The 2D fingerprint image 805 shown or Figure 42 The 2D fingerprint image 808 shown. Taking the target 2D fingerprint image as the 2D fingerprint image 808 as an example, as shown in FIG. Figure 43 As shown, the image lines 8081 of the target 3D fingerprint image may have a certain height.

[0325] It should be noted that Figure 43 This is only an example of the present application and should not be considered as limiting the present application.

[0326] For example, in other alternative embodiments, the heights of the pattern units in the image pattern 8081 may be partially or completely different. In other words, the upper surface of the image pattern 8081 may be an uneven curved surface.

[0327] In some embodiments of the present application, for each texture unit on each image line in the target 2D fingerprint image, the fingerprint detection device may use the width of each texture unit on each image line in the first 2D fingerprint image minus the width of the same texture unit on the same image line in the target 2D fingerprint image to obtain a target width corresponding to each texture unit on each image line in the target 2D fingerprint image; then, the fingerprint detection device may determine the height of each texture unit on each image line in the target 2D fingerprint image based on the target width corresponding to each texture unit on each image line in the target 2D fingerprint image.

[0328] Figure 44 Schematic diagram of the width of a texture unit of an image texture in a 2D fingerprint image according to an embodiment of the present application.

[0329] like Figure 44As shown, taking the first 2D fingerprint image as 2D fingerprint image 806 as an example, assuming that the upper surface of the ridge 809 of the sampling entity is a plane, the fingerprint detection device can determine the height of each line unit on each line in the target 2D fingerprint image according to the following formula:

[0330] H = K × d × tanθ;

[0331] Wherein, H represents the height of the texture unit on the image texture in the target 2D fingerprint image, K represents the reduction ratio of the projection of the sampling entity on the display screen to the first 2D fingerprint image, d represents the target width, and θ represents the angle between the light signal used to form the first 2D fingerprint image in the multiple directions of light signals and the finger spine.

[0332] In other words, the ridge 809 of the 3D fingerprint entity forms an angle θ with the light signal reflected by the 3D fingerprint entity, and a width of L+d texture units will be generated on the 2D fingerprint image 806, which is d wider than the width L of the texture units in the target 2D fingerprint image, that is, the texture generated on the side of the ridge 809 of the 3D fingerprint entity. Therefore, based on the above formula, the height of each texture unit can be obtained, and then the target 3D fingerprint image can be obtained based on the height of each texture unit on each image texture.

[0333] The present application also discloses a fingerprint recognition device for executing the method of the present application. The fingerprint recognition device is applicable to an electronic device having a display screen and is disposed below the display screen to implement under-screen fingerprint recognition.

[0334] Figure 45 It is a schematic block diagram of the fingerprint detection device 90 according to an embodiment of the present application.

[0335] like Figure 45 As shown, the fingerprint detection device 90 includes:

[0336] an optical sensing pixel array 910, configured to acquire light signals in multiple directions reflected by a sampling entity above the display screen;

[0337] A processor 920, connected to the optical sensing pixel array, configured to:

[0338] receiving the optical signals in the multiple directions sent by the optical sensing pixel array, and generating a plurality of 2D fingerprint images based on the optical signals in the multiple directions;

[0339] Determining whether the sampled entity is a three-dimensional (3D) entity based on the multiple 2D fingerprint images;

[0340] If the sampled entity is a 3D entity, fingerprint recognition is performed based on at least one 2D fingerprint image among the multiple 2D fingerprint images.

[0341] It should be understood that the processor 920 may be an image processor included in the fingerprint detection device 90 , or may be a processor of the electronic device to which the fingerprint detection device 90 belongs, such as a central processing unit.

[0342] In some embodiments of the present application, the processor 920 is specifically configured to:

[0343] determining whether the multiple 2D fingerprint images are identical;

[0344] If the multiple 2D fingerprint images are different, the sampled entity is determined to be a 3D entity.

[0345] In some embodiments of the present application, the processor 920 is further configured to:

[0346] If the curvatures of the same image texture of the multiple 2D fingerprint images are different, determining that the multiple 2D fingerprint images are different; and / or

[0347] If the widths of the lines of the same image in the multiple 2D fingerprint images are different, it is determined that the multiple 2D fingerprint images are different.

[0348] In some embodiments of the present application, the processor 920 is specifically configured to:

[0349] generating a target 2D fingerprint image based on the multiple 2D fingerprint images, wherein the image texture of the target 2D fingerprint image includes image textures where the multiple 2D fingerprint images overlap with each other;

[0350] Fingerprint recognition is performed based on the target 2D fingerprint image.

[0351] In some embodiments of the present application, the processor 920 is further configured to:

[0352] If the target 2D fingerprint image matches the pre-stored 2D fingerprint image, the fingerprint recognition is determined to be successful; and / or

[0353] If the target 2D fingerprint image fails to match the pre-stored 2D fingerprint image, it is determined that the fingerprint recognition has failed.

[0354] In some embodiments of the present application, the processor 920 is further configured to:

[0355] generating a target 3D fingerprint image based on the target 2D fingerprint image;

[0356] Fingerprint recognition is performed based on the target 3D fingerprint image.

[0357] In some embodiments of the present application, the processor 920 is further configured to:

[0358] determining, based on the target 2D fingerprint image and a first 2D fingerprint image among the multiple 2D fingerprint images, a height of each line unit on each image line in the target 2D fingerprint image;

[0359] The target 3D fingerprint image is generated based on the height of each line unit on each image line in the target 2D fingerprint image.

[0360] In some embodiments of the present application, the processor 920 is further configured to:

[0361] For each line element on each line in the target 2D fingerprint image, subtract the width of the same line element on the same line in the target 2D fingerprint image from the width of each line element on each line in the first 2D fingerprint image to obtain a target width corresponding to each line element on each line in the target 2D fingerprint image;

[0362] The height of each line unit on each line in the target 2D fingerprint image is determined based on the target width corresponding to each line unit on each line in the target 2D fingerprint image.

[0363] In some embodiments of the present application, the processor 920 is further configured to:

[0364] The height of each line unit on each line in the target 2D fingerprint image is determined according to the following formula:

[0365] H = K × d × tanθ;

[0366] Wherein, H represents the height of the same texture unit on the same image texture in the target 2D fingerprint image, K represents the reduction ratio of the projection of the sampling entity on the display screen to the 2D fingerprint image in the multiple 2D fingerprint images, d represents the target width, and θ represents the angle between the light signal used to form the first 2D fingerprint image in the multiple directions of light signals and the finger spine.

[0367] In some embodiments of the present application, the processor 920 is further configured to:

[0368] If the target 3D fingerprint image matches the pre-stored 3D fingerprint image, the fingerprint recognition is determined to be successful; and / or

[0369] If the target 3D fingerprint image fails to match the pre-stored 3D fingerprint image, it is determined that the fingerprint recognition has failed.

[0370] In some embodiments of the present application, the optical signals in multiple directions include optical signals perpendicular to the display screen and optical signals tilted relative to the display screen; or the optical signals in multiple directions include optical signals tilted relative to the display screen.

[0371] It should be understood that the fingerprint detection device 90 and the method 70 may correspond to each other, and similar descriptions may refer to the method embodiment. Specifically, Figure 45 The fingerprint detection device 90 shown can correspond to the corresponding subject in executing the method 70 of the embodiment of the present application, and the aforementioned and other operations and / or functions of each unit in the fingerprint detection device 90 are respectively for implementing the corresponding processes in the method 70. For the sake of brevity, they will not be repeated here.

[0372] It should also be understood that the method 70 can be implemented in hardware, software, or a combination of hardware and software modules. Specifically, the steps of the method embodiments in the embodiments of the present application can be implemented by hardware integrated logic circuits in a processor and / or software instructions. The steps of the method disclosed in the embodiments of the present application can be directly implemented by a hardware decoding processor, or by a combination of hardware and software modules in the decoding processor.

[0373] The software module may be located in a mature storage medium in the art, such as a random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, or register. The storage medium is located in the memory, and the processor reads the information in the memory and, in conjunction with its hardware, completes the steps in the above method embodiment.

[0374] The preferred embodiments of the present application are described in detail above in conjunction with the accompanying drawings. However, the present application is not limited to the specific details in the above embodiments. Within the technical concept of the present application, various simple modifications can be made to the technical solution of the present application, and these simple modifications all fall within the scope of protection of the present application.

[0375] For example, the various specific technical features described in the above specific embodiments can be combined in any appropriate manner without contradiction. In order to avoid unnecessary repetition, this application will not further describe various possible combinations.

[0376] For another example, the various implementation methods of the present application may be arbitrarily combined, and as long as they do not violate the concept of the present application, they should also be regarded as the contents disclosed in the present application.

[0377] It should be understood that in the various method embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0378] An embodiment of the present application also provides an electronic device, which may include a display screen and a fingerprint detection device according to the above-mentioned embodiment of the present application, wherein the fingerprint detection device is arranged below the display screen to realize under-screen optical fingerprint detection.

[0379] The electronic device may be any electronic device having a display screen. For example, the electronic device may be Figures 1 to 4 The electronic device 10 is shown in FIG.

[0380] The display screen can adopt the display screen described above, such as an OLED display screen or other display screen. For relevant instructions on the display screen, please refer to the description of the display screen in the above description. For the sake of brevity, it will not be repeated here.

[0381] It should be understood that the specific examples in the embodiments of the present application are only intended to help those skilled in the art better understand the embodiments of the present application, rather than to limit the scope of the embodiments of the present application.

[0382] It should be understood that the terms used in the embodiments of the present application and the appended claims are for the purpose of describing specific embodiments only and are not intended to limit the embodiments of the present application. For example, the singular forms "a," "above," and "the" used in the embodiments of the present application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0383] Those skilled in the art will appreciate that the units of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in terms of function in the above description. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0384] In the several embodiments provided in this application, it should be understood that the disclosed systems and devices can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of the units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or units, or can be electrical, mechanical or other forms of connection.

[0385] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the embodiments of the present application.

[0386] In addition, the functional units in the various embodiments of the present application may be integrated into a single processing unit, or each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0387] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application is essentially or partly contributed to the prior art, or all or part of the technical solution can be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0388] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present application, and such modifications or substitutions should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A method for identifying fingerprints, characterized in that: Applicable to electronic devices with display screens to implement under-screen fingerprint recognition, the method includes: Obtaining optical signals in multiple directions reflected by a sampling entity above the display screen and guided and transmitted by each of a plurality of fingerprint detection units in a fingerprint detection device, wherein each fingerprint detection unit includes a microlens, at least one light-blocking layer, and a plurality of optical sensing pixels, wherein the microlens is disposed above the plurality of optical sensing pixels, the at least one light-blocking layer is disposed between the microlens and the plurality of optical sensing pixels, and each of the at least one light-blocking layer is provided with an opening to form a plurality of light-guiding channels corresponding to the microlens, the plurality of light-guiding channels having different directions and being used to guide and transmit the optical signals in the multiple directions; Based on the light signals in the multiple directions, a plurality of two-dimensional 2D fingerprint images are generated respectively, wherein the light signal in each direction of the multiple directions is used to generate one 2D fingerprint image among the multiple 2D fingerprint images; Determining whether the sampled entity is a three-dimensional (3D) entity based on the multiple 2D fingerprint images; If the sampled entity is a 3D entity, fingerprint recognition is performed based on at least one 2D fingerprint image among the multiple 2D fingerprint images.

2. The method according to claim 1, characterized in that The determining, based on the multiple 2D fingerprint images, whether the sampled entity is a three-dimensional (3D) entity comprises: determining whether the multiple 2D fingerprint images are identical; If the multiple 2D fingerprint images are different, the sampled entity is determined to be a 3D entity.

3. The method according to claim 2, characterized in that Determining whether the multiple 2D fingerprint images are identical includes: If the curvatures of the same image texture of the multiple 2D fingerprint images are different, determining that the multiple 2D fingerprint images are different; and / or If the widths of the lines of the same image in the multiple 2D fingerprint images are different, it is determined that the multiple 2D fingerprint images are different.

4. The method according to claim 1, wherein The performing fingerprint recognition based on at least one 2D fingerprint image among the multiple 2D fingerprint images includes: generating a target 2D fingerprint image based on the multiple 2D fingerprint images, wherein the image texture of the target 2D fingerprint image includes image textures where the multiple 2D fingerprint images overlap with each other; Fingerprint recognition is performed based on the target 2D fingerprint image.

5. The method according to claim 4, characterized in that The performing fingerprint recognition based on the target 2D fingerprint image includes: If the target 2D fingerprint image matches the pre-stored 2D fingerprint image, the fingerprint recognition is determined to be successful; and / or If the target 2D fingerprint image fails to match the pre-stored 2D fingerprint image, it is determined that the fingerprint recognition has failed.

6. The method according to claim 4, characterized in that The performing fingerprint recognition based on the target 2D fingerprint image includes: generating a target 3D fingerprint image based on the target 2D fingerprint image; Fingerprint recognition is performed based on the target 3D fingerprint image.

7. The method according to claim 6, characterized in that The generating of a target 3D fingerprint image based on the target 2D fingerprint image includes: determining, based on the target 2D fingerprint image and a first 2D fingerprint image among the multiple 2D fingerprint images, a height of each line unit on each image line in the target 2D fingerprint image; The target 3D fingerprint image is generated based on the height of each line unit on each image line in the target 2D fingerprint image.

8. The method according to claim 7, characterized in that The determining, based on the target 2D fingerprint image and a first 2D fingerprint image among the multiple 2D fingerprint images, a height of each line unit on each image line in the target 2D fingerprint image includes: For each line element on each line in the target 2D fingerprint image, subtract the width of the same line element on the same line in the target 2D fingerprint image from the width of each line element on each line in the first 2D fingerprint image to obtain a target width corresponding to each line element on each line in the target 2D fingerprint image; The height of each line unit on each line in the target 2D fingerprint image is determined based on the target width corresponding to each line unit on each line in the target 2D fingerprint image.

9. The method according to claim 8, characterized in that The determining, based on the target width corresponding to each line unit on each line in the target 2D fingerprint image, the height of each line unit on each line in the target 2D fingerprint image includes: The height of each line unit on each line in the target 2D fingerprint image is determined according to the following formula: H = K × d × tanθ; Wherein, H represents the height of the texture unit on the image texture in the target 2D fingerprint image, K represents the reduction ratio of the projection of the sampling entity on the display screen to the first 2D fingerprint image, d represents the target width, and θ represents the angle between the light signal used to form the first 2D fingerprint image in the multiple directions and the finger spine.

10. The method according to claim 6, characterized in that The performing fingerprint recognition based on the target 3D fingerprint image includes: If the target 3D fingerprint image matches the pre-stored 3D fingerprint image, the fingerprint recognition is determined to be successful; and / or If the target 3D fingerprint image fails to match the pre-stored 3D fingerprint image, it is determined that the fingerprint recognition has failed.

11. The method according to any one of claims 1 to 10, characterized in that The optical signals in the multiple directions include optical signals perpendicular to the display screen and optical signals tilted relative to the display screen; or the optical signals in the multiple directions include optical signals tilted relative to the display screen.

12. The method according to any one of claims 1 to 10, characterized in that The at least one light-blocking layer is a multi-layer light-blocking layer, and the top light-blocking layer of the multi-layer light-blocking layer is provided with an opening corresponding to the multiple optical sensing pixels, or is provided with multiple openings respectively corresponding to the multiple optical sensing pixels; the bottom light-blocking layer of the at least one light-blocking layer is provided with multiple openings respectively corresponding to the multiple optical sensing pixels, so that the microlens converges the light signals in the multiple directions to the multiple optical sensing pixels respectively through the multiple openings; The apertures in the at least one light-blocking layer corresponding to the same optical sensing pixel decrease in size from top to bottom.

13. The method according to claim 12, characterized in that The fingerprint detection unit includes a microlens and four optical sensing pixels distributed in a rectangular array, and the at least one light-blocking layer includes a top light-blocking layer and a bottom light-blocking layer; The top light-blocking layer is provided with one opening corresponding to the four optical sensing pixels below the one microlens, or the top light-blocking layer is provided with four openings corresponding to the four optical sensing pixels respectively below the one microlens; The bottom light-blocking layer is provided with four openings corresponding to the four optical sensing pixels respectively below the one microlens.

14. A fingerprint recognition device, characterized in that: The fingerprint recognition device is suitable for electronic devices with a display screen and is arranged below the display screen to realize under-screen fingerprint recognition; The fingerprint recognition device comprises: Multiple fingerprint detection units, each of the multiple fingerprint detection units comprising a microlens, at least one light-blocking layer, and multiple optical sensing pixels, wherein the microlens is disposed above the multiple optical sensing pixels, the at least one light-blocking layer is disposed between the microlens and the multiple optical sensing pixels, and each of the at least one light-blocking layer is provided with an opening to form multiple light-guiding channels corresponding to the microlens, the multiple light-guiding channels having different directions, and the multiple light-guiding channels are used to guide and transmit optical signals in the multiple directions; an optical sensing pixel array, the optical sensing pixel array being configured to acquire optical signals in multiple directions that are reflected by a sampling entity above the display screen and guided and transmitted by light guide channels of the multiple fingerprint detection units; A processor connected to the optical sensing pixel array, wherein the processor is configured to: receiving optical signals in multiple directions sent by the optical sensing pixel array via the multiple fingerprint detection units, and generating a plurality of two-dimensional 2D fingerprint images based on the optical signals in the multiple directions, wherein each optical signal in the multiple directions is used to generate one 2D fingerprint image among the multiple 2D fingerprint images; Determining whether the sampled entity is a three-dimensional (3D) entity based on the multiple 2D fingerprint images; If the sampled entity is a 3D entity, fingerprint recognition is performed based on at least one 2D fingerprint image among the multiple 2D fingerprint images.

15. The fingerprint recognition device according to claim 14, characterized in that: The processor is specifically configured to: determining whether the multiple 2D fingerprint images are identical; If the multiple 2D fingerprint images are different, the sampled entity is determined to be a 3D entity.

16. The fingerprint recognition device according to claim 15, characterized in that: The processor is more specifically configured to: If the curvatures of the same image texture of the multiple 2D fingerprint images are different, determining that the multiple 2D fingerprint images are different; and / or If the widths of the lines of the same image in the multiple 2D fingerprint images are different, it is determined that the multiple 2D fingerprint images are different.

17. The fingerprint recognition device according to claim 14, wherein: The processor is specifically configured to: generating a target 2D fingerprint image based on the multiple 2D fingerprint images, wherein the image texture of the target 2D fingerprint image includes image textures where the multiple 2D fingerprint images overlap with each other; Fingerprint recognition is performed based on the target 2D fingerprint image.

18. The fingerprint recognition device according to claim 17, characterized in that: The processor is more specifically configured to: If the target 2D fingerprint image matches the pre-stored 2D fingerprint image, the fingerprint recognition is determined to be successful; and / or If the target 2D fingerprint image fails to match the pre-stored 2D fingerprint image, it is determined that the fingerprint recognition has failed.

19. The fingerprint recognition device according to claim 17, wherein: The processor is more specifically configured to: generating a target 3D fingerprint image based on the target 2D fingerprint image; Fingerprint recognition is performed based on the target 3D fingerprint image.

20. The fingerprint recognition device according to claim 19, characterized in that: The processor is more specifically configured to: determining, based on the target 2D fingerprint image and a first 2D fingerprint image among the multiple 2D fingerprint images, a height of each line unit on each image line in the target 2D fingerprint image; The target 3D fingerprint image is generated based on the height of each line unit on each image line in the target 2D fingerprint image.

21. The fingerprint recognition device according to claim 20, characterized in that: The processor is more specifically configured to: For each line element on each line in the target 2D fingerprint image, subtract the width of the same line element on the same line in the target 2D fingerprint image from the width of each line element on each line in the first 2D fingerprint image to obtain a target width corresponding to each line element on each line in the target 2D fingerprint image; The height of each line unit on each line in the target 2D fingerprint image is determined based on the target width corresponding to each line unit on each line in the target 2D fingerprint image.

22. The fingerprint recognition device according to claim 21, characterized in that: The processor is more specifically configured to: The height of each line unit on each line in the target 2D fingerprint image is determined according to the following formula: H = K × d × tanθ; Wherein, H represents the height of the same texture unit on the same image texture in the target 2D fingerprint image, K represents the reduction ratio of the projection of the sampling entity on the display screen to the 2D fingerprint image in the multiple 2D fingerprint images, d represents the target width, and represents the angle between the light signal used to form the first 2D fingerprint image in the multiple directions of light signals and the finger spine.

23. The fingerprint recognition device according to claim 19, characterized in that: The processor is more specifically configured to: If the target 3D fingerprint image matches the pre-stored 3D fingerprint image, the fingerprint recognition is determined to be successful; and / or If the target 3D fingerprint image fails to match the pre-stored 3D fingerprint image, it is determined that the fingerprint recognition has failed.

24. The fingerprint recognition device according to any one of claims 14 to 23, characterized in that: The optical signals in the multiple directions include optical signals perpendicular to the display screen and optical signals tilted relative to the display screen; or the optical signals in the multiple directions include optical signals tilted relative to the display screen.

25. The fingerprint recognition device according to any one of claims 14 to 23, characterized in that: The at least one light-blocking layer is a multi-layer light-blocking layer, and a top light-blocking layer of the multi-layer light-blocking layer is provided with an opening corresponding to the plurality of optical sensing pixels, or is provided with a plurality of openings corresponding to the plurality of optical sensing pixels respectively; The bottom light-blocking layer of the at least one light-blocking layer is provided with a plurality of openings corresponding to the plurality of optical sensing pixels, so that the microlens converges the light signals in the plurality of directions to the plurality of optical sensing pixels respectively through the plurality of openings; The apertures in the at least one light-blocking layer corresponding to the same optical sensing pixel decrease in size from top to bottom.

26. The fingerprint recognition device according to claim 25, characterized in that: The fingerprint detection unit includes a microlens and four optical sensing pixels distributed in a rectangular array, and the at least one light-blocking layer includes a top light-blocking layer and a bottom light-blocking layer; The top light-blocking layer is provided with one opening corresponding to the four optical sensing pixels below the one microlens, or the top light-blocking layer is provided with four openings corresponding to the four optical sensing pixels respectively below the one microlens; The bottom light-blocking layer is provided with four openings corresponding to the four optical sensing pixels respectively below the one microlens.

27. An electronic device, characterized in that: include: Display screen; as well as The fingerprint recognition device according to any one of claims 14 to 26, wherein the fingerprint recognition device is arranged below the display area of ​​the display screen to achieve under-screen fingerprint recognition.

Images