Fingerprint detection device and method thereof and electronic device

Abstract

The present application discloses a fingerprint detection device, comprising a light source and an image module. The light source is used to emit a detection beam to the finger of the object to be detected. The image module is used to receive the detection beam reflected from the finger of the object to be detected and convert it into a corresponding electrical signal to generate a fingerprint image of the object to be detected, and the fingerprint image of the object to be detected displays ridges, valleys and sweat pores. The fingerprint image of the object to be detected is used to confirm whether the object to be detected is alive. The present application also discloses a fingerprint detection method and an electronic device.

Description

Technical Field

[0001] The present application relates to the field of optoelectronic technology, and in particular to a fingerprint detection device and method thereof, and an electronic device. Background Art

[0002] With the rapid development of science and technology, fingerprint detection is widely used in security, access control, attendance and even identity authentication on terminal devices. At present, during the fingerprint detection process, the terminal obtains the fingerprint image through the fingerprint acquisition component, and performs feature matching on the fingerprint image and the pre-collected fingerprint template to obtain the fingerprint matching degree. If the fingerprint matching degree is greater than the matching degree threshold, it is determined that the collected fingerprint has passed the verification. However, common fingerprint detection schemes lack reliable liveness detection and are easily defrauded by prosthetic fingerprints made of silicone or the like. Summary of the invention

[0003] In order to solve the above technical problems, the present application provides a fingerprint detection device and method and an electronic device with liveness detection.

[0004] One aspect of the present application provides a fingerprint detection device, comprising a light source, for emitting a detection light beam to a finger of an object to be detected; an image module, for receiving the detection light beam reflected from the finger of the object to be detected and converting it into a corresponding electrical signal to generate a fingerprint image of the object to be detected, wherein the fingerprint image of the object to be detected includes sweat pore feature information and / or sweat pore feature information, and the light source is located around or below the image module; the image module comprises an image sensor, a processing unit and a storage unit, wherein: the processing unit can be used to obtain the sweat pore feature information of the fingerprint image of the object to be detected, and when the quantized value of the sweat pore feature information of the fingerprint image of the object to be detected is greater than or equal to a preset sweat pore feature information threshold, the processing unit obtains the sweat pore feature information of the fingerprint image of the object to be detected. The processing unit obtains the sweat pore feature information and the texture feature information of the fingerprint image of the object to be detected, and compares them with the pre-collected reference fingerprint image stored in the storage unit to confirm whether the object to be detected is a live authorized user; or: the processing unit obtains the sweat pore feature information and the texture feature information of the fingerprint image of the object to be detected, and compares them with the pre-collected reference fingerprint image stored in the storage unit to confirm whether the object to be detected is a live authorized user; the image sensor is exposed multiple times to acquire multiple fingerprint images of the object to be detected, the multiple exposures of the image sensor have different exposure times and / or the light source provides detection light beams with different light intensities when the image sensor is exposed, so that at least part of the multiple fingerprint images have different average brightness.

[0005] In some embodiments of the present application, the fingerprint detection device also includes a glass cover plate, which is located above the light source and the image module. The detection light beam passes through the glass cover plate and irradiates the finger of the object to be detected. After being reflected on the finger of the object to be detected, the detection light beam passes through the glass cover plate and is received by the image module and converted into a corresponding electrical signal.

[0006] In some embodiments of the present application, the upper surface of the glass cover plate has a detection area, and the fingerprint detection device also includes a control unit, which is used to sense whether the finger of the object to be detected contacts the detection area, control the light source and the image module to turn on when the finger of the object to be detected approaches or contacts the detection area, and control the light source and the image module to turn off when the fingerprint detection is completed or the finger of the object to be detected leaves the detection area.

[0007] In some embodiments of the present application, the fingerprint detection device is configured to distinguish the sweat pores in the fingerprint image by virtue of the refractive index of sweat being lower than the refractive index of the skin of the finger.

[0008] In some embodiments of the present application, the image module includes an image sensor for receiving a detection light beam and converting it into an electrical signal, the image sensor includes a substrate, a pixel array located on the substrate, and a microlens array located above the pixel array; the microlens array includes a plurality of microlenses arranged in an array, the pixel array includes a plurality of pixel units arranged in an array, wherein each of the microlenses corresponds to a plurality of the pixel units, and the focal length of the microlens and the distribution density of the plurality of microlenses are positively correlated with the thickness of the image module.

[0009] In some embodiments of the present application, the substrate has a plurality of grooves opened on a side or around the pixel array, the light source includes a plurality of light-emitting units, at least some of the light-emitting units are arranged in the plurality of grooves, and the light-emitting units arranged in the grooves are top-emitting type; or: the light source includes a plurality of light-emitting units, and the plurality of light-emitting units are dispersedly arranged around the image module, and at least some of the plurality of light-emitting units are side-emitting type or top-emitting type.

[0010] In some embodiments of the present application, the detection light beam is visible light, and the visible light includes green light; or the detection light beam includes invisible light, and the invisible light includes infrared light or near-infrared light.

[0011] One aspect of the present application provides a fingerprint detection method, comprising: obtaining a fingerprint image of an object to be detected, the fingerprint image showing ridges, valleys and sweat pores; obtaining fingerprint feature information of the object to be detected based on the fingerprint image of the object to be detected, the fingerprint feature information including sweat pore feature information and ridge and valley feature information; performing feature information comparison between the fingerprint image and a reference fingerprint image of an authorized user collected in advance to obtain a feature matching value, the feature information comparison including sweat pore feature information comparison and ridge and valley feature information comparison; judging whether the object to be detected is alive based on the feature matching value.

[0012] In some embodiments of the present application, the feature matching value includes a sweat pore feature matching value and a ridge valley feature matching value. When the sweat pore feature matching value is greater than or equal to a first threshold and the ridge valley feature matching value is greater than or equal to a second threshold, the object to be detected is a living body.

[0013] In some embodiments of the present application, the sweat pore characteristic information includes at least one of sweat pore size, sweat pore position, and sweat pore grayscale.

[0014] In some embodiments of the present application, the ridge-valley feature information includes ridge line information and valley line information formed by alternating ridge lines and valley lines.

[0015] In some embodiments of the present application, the fingerprint feature information also includes average grayscale information, and the average grayscale information is the average grayscale size of the sweat pores and the ridges where they are located, and the fingerprint feature comparison also includes average grayscale information comparison.

[0016] In some embodiments of the present application, the feature matching value also includes an average grayscale matching value. When the average grayscale matching value is greater than or equal to a third threshold, the object to be detected is a living body.

[0017] In some embodiments of the present application, the sweat pore feature information comparison, the ridge and valley feature information comparison and the average grayscale information comparison are compared separately.

[0018] In some embodiments of the present application, the sweat pores corresponding to the sweat pore characteristic information are displayed on the fingerprint image of the object to be detected as being completely located within the ridge line.

[0019] One aspect of the present application provides an electronic device, which includes the above-mentioned fingerprint detection device, or the electronic device adopts the above-mentioned fingerprint detection method.

[0020] The fingerprint detection device and method of the present application use multiple comparison methods such as ridge and valley feature information comparison and sweat pore feature information comparison to compare and analyze fingerprint feature information. Since sweat pores are difficult to fake, combining the ridge and valley features of fingerprints can better achieve liveness detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The drawings herein are incorporated into the specification and constitute a part of the specification, illustrate embodiments consistent with the present application, and are used together with the specification to explain the principles of the present application. In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the description of the embodiments are briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor.

[0022] Figure 1 It is a partial exploded schematic diagram of an embodiment of a fingerprint detection device of the present application;

[0023] Figure 2 yes Figure 1 A schematic diagram of some interfaces of the fingerprint detection device;

[0024] Figure 3 yes Figure 1 A partial exploded diagram of the image module in the middle;

[0025] Figure 4 yes Figure 3 A partial enlarged interface diagram of the image module;

[0026] Figure 5 It is a schematic diagram of microlens convergence imaging;

[0027] Figure 6 It is a partial schematic diagram of a fingerprint image generated by the image module.

[0028] Figure 7 It is a flowchart of an embodiment of the fingerprint detection method of the present application;

[0029] Figure 8 It is a block diagram of an embodiment of an electronic device of the present application.

[0030] The realization of the purpose, functional features and advantages of this application will be further described in conjunction with the embodiments and with reference to the accompanying drawings. The above-mentioned drawings have shown clear embodiments of this application, which will be described in more detail later. These drawings and textual descriptions are not intended to limit the scope of the concept of this application in any way, but to illustrate the concept of this application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0031] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the present application. Instead, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

[0032] It should be noted that, in this article, the terms "include", "comprises" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "includes a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element. In addition, components, features, and elements with the same name in different embodiments of the present application may have the same meaning or different meanings, and their specific meanings need to be determined by their explanation in the specific embodiment or further combined with the context of the specific embodiment.

[0033] It should be understood that, although the terms first, second, third, etc. may be used to describe various information in this article, these information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of this article, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Depending on the context, the word "if" as used herein can be interpreted as "at the time of..." or "when..." or "in response to determination". Furthermore, as used in this article, the singular forms "one", "one" and "the" are intended to also include plural forms, unless there is an opposite indication in the context. It should be further understood that the terms "comprising", "including" indicate that there are described features, steps, operations, elements, components, projects, kinds, and / or groups, but do not exclude the existence, occurrence or addition of one or more other features, steps, operations, elements, components, projects, kinds, and / or groups. The terms "or", "and / or", "including at least one of the following" etc. used in this application can be interpreted as inclusive, or mean any one or any combination. For example, “comprising at least one of the following: A, B, C” means “any of the following: A; B; C; A and B; A and C; B and C; A and B and C”, and for another example, “A, B or C” or “A, B and / or C” means “any of the following: A; B; C; A and B; A and C; B and C; A and B and C”. An exception to this definition will only occur when a combination of elements, functions, steps or operations are inherently mutually exclusive in some manner.

[0034] It should be understood that, although the various steps in the flowchart in the embodiment of the present application are displayed in sequence according to the indication of the arrows, these steps are not necessarily performed in sequence in the order indicated by the arrows. Unless there is a clear explanation in this article, the execution of these steps does not have a strict order restriction, and it can be performed in other orders. Moreover, at least a portion of the steps in the figure may include a plurality of sub-steps or a plurality of stages, and these sub-steps or stages are not necessarily performed at the same time, but can be performed at different times, and their execution order is not necessarily performed in sequence, but can be performed in turn or alternately with other steps or at least a portion of the sub-steps or stages of other steps.

[0035] As used herein, the words "if" and "if" may be interpreted as "at the time of" or "when" or "in response to determining" or "in response to detecting", depending on the context. Similarly, the phrases "if it is determined" or "if (stated condition or event) is detected" may be interpreted as "when it is determined" or "in response to determining" or "when detecting (stated condition or event)" or "in response to detecting (stated condition or event)", depending on the context.

[0036] It should be noted that in this article, step codes such as S10 and S20 are used for the purpose of expressing the corresponding content more clearly and concisely, and do not constitute a substantial limitation on the sequence. When implementing the step, those skilled in the art may execute S20 first and then S10, etc., but these should all be within the scope of protection of this application.

[0037] It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0038] In the subsequent description, the suffixes such as "module", "component" or "unit" used to represent elements are only used to facilitate the description of the present application, and have no specific meanings. Therefore, "module", "component" or "unit" can be used in a mixed manner.

[0039] Electronic devices can be configured with a fingerprint detection function to improve the security of users accessing electronic devices. Such electronic devices include, but are not limited to, smartphones, tablet computers, wrist-worn devices and other wearable or portable devices, laptops, personal computers, ATMs, electronic billboards, various display terminals, etc., or cars, ships, trains, airplanes, etc.

[0040] See also Figure 1, is a partially exploded schematic diagram of an embodiment of the fingerprint detection device 1 of the present application. The fingerprint detection device 1 includes an image module 10, a light source 20 located around the image module, a base plate 30 and a glass cover plate 40. The image module 10 and the light source 20 are arranged on the base plate 30. Optionally, in some embodiments, the glass cover plate 40 can be connected to the base plate 30 through a connecting portion 50.

[0041] Optionally, in some embodiments, the bottom plate 30 may be a reinforced plate, such as but not limited to a steel plate. In other embodiments, the bottom plate 30 may be omitted, and the image module 10 and the light source 20 may be disposed on an external component, such as being bonded or connected to an external circuit board via foam, which is not limited in the present embodiment.

[0042] Optionally, in some embodiments, the light source 20 may include a plurality of light emitting units 21 , and the light emitting units 21 may be dispersed around the image module 10 , or the light emitting units 21 may be at least disposed on one side of the image module 10 . Figure 1 The image module 10 shown in the figure has a substantially rectangular boundary, and the plurality of light emitting units 21 are respectively located around the image module 10 and can emit light beams from different directions, so that the fingerprint image imaging quality of the image module 10 is better.

[0043] Optionally, in some embodiments, the light source 20 may include a plurality of light emitting units 21, and the light emitting units 21 may be disposed on the image sensor 10. For example, but not limited to, the peripheral idle area of ​​the circuit substrate of the image sensor 10 may have an opening or groove suitable for accommodating at least part of the light emitting unit 21. The light emitting unit 21 may be a top-emitting light emitting element. The closer connection between the light source 20 and the image sensor 10 makes the overall volume of the fingerprint detection device 1 more compact and can save space.

[0044] Please also read Figure 2, is a partial cross-sectional schematic diagram of the fingerprint detection device 1. When the finger 100 of the object to be detected contacts the upper surface of the glass cover plate 40, the fingerprint detection device 1 works normally. The light-emitting unit 21 emits a detection light beam 101, and the detection light beam 101 passes through the glass cover plate 40 to illuminate the finger 100 of the object to be detected and is reflected. The partially reflected detection light beam 101 passes through the glass cover plate 40 and reaches the image module 10. The image module 10 receives the detection light beam 101 returned by the finger 100 and converts it into a corresponding electrical signal, generates a corresponding fingerprint image, and can be used to confirm whether the finger 100 and the object to be detected are alive. Optionally, in some embodiments, the light-emitting unit 21 can be a side-emitting light-emitting element or a top-emitting light-emitting element. For example, but not limited to, the light-emitting unit 21 can include a light-emitting diode (LED).

[0045] Since there are ridges and valleys between the fingers, when the finger 100 contacts the glass cover plate 40, the ridges of the finger 100 directly contact the surface of the glass cover plate 40, and there is a spacer (such as air or water) between the valleys of the finger 100 and the surface of the glass cover plate 40. Therefore, the detection beams 101 returned from the ridges and valleys of the finger 100 have different reflectivities, and the image module 10 can collect and distinguish the different detection beams 101 returned from the ridges and valleys, and then use them to generate ridge lines and valley lines corresponding to the ridges and valleys of the finger 100.

[0046] In addition, since the refractive index of sweat is lower than that of the finger skin, the energy of the detection beam 101 returned from the sweat pores is different from that of the detection beam 101 returned from other areas of the finger skin. The image module 10 collects the detection beam 101 returned from the sweat pores and ridges and valleys and can be used to generate a fingerprint image with corresponding sweat pore feature information and pattern (usually the pattern is formed by spaced ridges and valleys) feature information. In some embodiments, in the fingerprint image generated by the image module 10, for the sweat pores located in the area where the ridges of the finger 100 are located, the sweat pore feature information is significantly different from the ridge feature information where the ridges are located. Since the configuration of the sweat pores on the ridges of the finger skin is inherent like fingerprints and voiceprints, and will not be covered in a lifetime. It is difficult for a prosthetic finger to imitate the complex and unique sweat pore features of a living finger. Therefore, by detecting the sweat pore features of the finger 100, it is possible to better confirm whether the finger 100 and the object to be detected are living, and whether the object to be detected is an authorized user. Generally, the fingerprint image of the authorized user can be collected in advance and stored in the fingerprint database as a reference fingerprint image.

[0047] Optionally, in some embodiments, the fingerprint image of the object to be detected can be used to compare with a pre-collected reference fingerprint image using sweat pores and / or lines to confirm whether the object to be detected is alive, and further confirm whether the object to be detected is an authorized user.

[0048] Optionally, in some embodiments, the fingerprint detection device 1 first collects the fingerprint image information of the object to be detected and detects whether there is enough sweat pore feature information. For example, but not limited to, when the quantized value of the sweat pore feature information is less than the preset sweat pore feature information threshold, it is judged that the object to be detected is not a living body, and it is obviously not an authorized user. At this time, a reminder can be directly made through a display device or a sound device. When the quantized value of the sweat pore feature information reaches the preset sweat pore feature information threshold, the object to be detected is considered to be a living body. The fingerprint detection device 1 can compare the fingerprint image of the object to be detected with the pre-collected reference fingerprint image, and confirm whether the object to be detected is an authorized user through the comparison result. The comparison result can be represented by a matching value. When the matching value is less than the preset matching threshold, it is considered that the object to be detected is not an authorized user, and when the matching value is greater than or equal to the preset matching threshold, it is considered that the object to be detected is a living authorized user. It can be understood that if a fake user uses a forged fingerprint set to try to use the fingerprint detection device 1 for identity authentication, the fake user may be the object to be detected. Considering that sweat pore features are difficult to forge and costly, fingerprint covers are usually difficult to have sweat pores, so the fingerprint image from the fingerprint cover obtained by the fingerprint detection device 1 is likely to have no detailed sweat pore feature information. Based on this, it can be determined that the user is not an authorized user.

[0049] Optionally, in some embodiments, the fingerprint detection device 1 compares the fingerprint image of the object to be detected with a pre-collected reference fingerprint image, and confirms whether the object to be detected is an authorized user through the comparison result. The comparison result can be represented by a matching value. When the matching value is less than a preset matching threshold, the object to be detected is considered not to be an authorized user, and when the matching value is greater than or equal to the preset matching threshold, the object to be detected is considered to be an authorized user. The above-mentioned comparison can be compared using at least biometric information such as sweat pore feature information and / or grain feature information (including ridge feature information and / or valley feature information) to obtain corresponding comparison results. The comparison result may include multiple matching values, corresponding to the sweat pore feature matching degree, grain feature matching degree, etc., respectively. According to the preset fingerprint data model and parameters, the fingerprint detection device 1 can confirm whether the object to be detected is a live authorized user.

[0050] Optionally, in some embodiments, the optical signal collected by the image module 10 is converted into an electrical signal and processed to generate a fingerprint image of the object to be detected. The fingerprint image of the object to be detected can be an image with a size of M pixels*N pixels, where M and N are both positive integers.

[0051] Optionally, in some embodiments, the image module 10 can be used to generate images with different biometric information to perform corresponding detection. The biometric information can be fingerprint feature information, palm print feature information, blood oxygen feature information, etc., and the present application is not limited thereto.

[0052] Optionally, in some embodiments, a pulse signal on the optical properties is generated due to blood flowing through the blood vessels of the finger 100. For example, blood cells exhibit different optical absorption spectral characteristics at visible wavelengths (e.g., higher optical absorption) and near-infrared wavelengths (e.g., lower optical absorption compared to visible wavelengths). Such different optical absorption characteristics of blood can be captured by the image module 10. Other characteristics of blood flow can be reflected by pressure changes in blood vessels. When the detection light beam 101 propagates into the tissue or blood cells of the finger 100, the detection light beam 101 is partially absorbed and partially scattered. Living finger movement or blood flow can cause changes in the light absorption cross section. The image module 10 is capable of detecting such changes.

[0053] Optionally, in some embodiments, the fingerprint detection device 1 can be used to detect the color corresponding to the blood concentration of the finger 100 to confirm whether the finger 100 is alive. Since the living finger contains flowing blood, in the natural state where the finger is not subjected to force, the blood in the finger evenly fills the end of the finger, making the end of the finger appear light red. When the finger 100 presses the glass cover plate 40, the blood flows away from the part of the finger 100 in contact with the glass cover plate 40 due to the force, which reduces the blood concentration in this area. Therefore, in the process from when the finger 100 and the glass cover plate 40 just touch to when the finger 100 fully presses the glass cover plate 40, the color of the part of the finger 100 in contact with the glass cover plate 40 will change significantly from light red to light yellow. However, the materials currently used to forge fingers (such as plastic, silicone, paper, etc.) do not show obvious color changes on their surfaces during the pressing process. Therefore, by detecting the color change of the finger 100 in the process of pressing the glass cover plate 40, the authenticity of the finger 100 can be effectively identified.

[0054] Optionally, in some embodiments, the fingerprint detection device 1 may include a pressure sensor for detecting contact, pressure, movement, extension or pulsation of the finger 100; or the fingerprint detection device 1 may include any other suitable sensor for detecting contact, pressure, movement, extension or pulsation of the finger 100.

[0055] It is understandable that the detection light beam 101 returned by the finger 100 may include but is not limited to the detection light beam 101 reflected by the surface of the finger 100 and the detection light beam 101 or other light beams returned by being transmitted through the surface from the inside of the finger 100 .

[0056] Optionally, in some embodiments, the detection light beam 101 is visible light, and the visible light includes green light.

[0057] Optionally, in some embodiments, the detection light beam 101 includes invisible light, and the invisible light includes infrared light or near-infrared light.

[0058] Please also read Figure 3 , is a partially exploded schematic diagram of the image module 10. The image module 10 includes a microlens array 11, a light shielding layer 12, a substrate 13 and an image sensor 14 arranged in sequence from top to bottom. The microlens array 11 includes a plurality of microlenses 111 arranged in an array, and the light shielding layer 12 is provided with a plurality of openings 121 arranged in an array, and the openings 121 correspond to the microlenses 111 one by one. The microlenses 111 are distributed at intervals, and the light shielding layer 12 is arranged at the intervals between the microlenses 111. The light shielding layer 12 is made of black material, which can block the transmission of visible light.

[0059] The microlens 111 generally has a circular bottom surface (not marked) and an arched protrusion (not marked). The microlens 111 is used to converge a light beam from above. The light beam can enter the microlens 111 from the rounded surface of the arched protrusion, and pass through the opening 112 and the substrate 13 from the bottom surface of the microlens 111 to reach the image sensor 14. The image sensor 14 is used to receive the light beam and convert it into an electrical signal, which can be a voltage signal, a current signal, etc. The electrical signal can be used to generate a fingerprint image.

[0060] In some embodiments, the image module 10 may further include a processing unit and a storage unit. The processing unit can be used to obtain the sweat pore feature information of the fingerprint image of the object to be detected, and when the quantized value of the sweat pore feature information of the fingerprint image of the object to be detected is greater than or equal to the preset sweat pore feature information threshold, the processing unit obtains the texture feature information of the fingerprint image of the object to be detected, and compares the sweat pore feature information and / or texture feature information with the reference fingerprint image pre-collected and stored in the storage unit to confirm whether the object to be detected is a live authorized user, or the processing unit obtains the sweat pore feature information and texture feature information of the fingerprint image of the object to be detected, and compares them with the pre-collected reference fingerprint image stored in the storage unit to confirm whether the object to be detected is a live authorized user.

[0061] Please also read Figure 4 , the image sensor 14 may include a pixel array 141, and the pixel array 141 includes a plurality of pixel units 1411 arranged in an array. Each pixel unit 1411 includes, for example but not limited to, one or more photodiodes, which can convert light signals into electrical signals. The detection light beam 101 returned by the finger 100 is converged by the microlens 111 and reaches the pixel array 141. In the embodiment of the present application, each microlens 111 may correspond to a plurality of pixel units 1411. Figure 4 As shown, each microlens 111 corresponds to a field of view area VA having a certain diameter on the upper surface of the glass cover plate 40, and a portion of the finger 100 contacting the field of view area VA can return the detection light beam 101 to the image sensor 14 through the corresponding microlens 111. The center spacing of the microlenses 111 is P, and the bottom diameter of the microlens 111 is d. Optionally, in some embodiments, P≥d or P≥2d or P≥3d or P≥4d.

[0062] When the value of P / d is larger, the density of the microlens 111 distributed above the pixel array 141 is smaller. It can be understood that a single microlens 111 needs to cover a larger field of view area VA accordingly, and a single microlens 111 corresponds to more pixel units 1411. At this time, the microlens 111 has a larger image distance, object distance and focal length accordingly. Optionally, in some embodiments, the focal length of the microlens 111 and the distribution density of the multiple microlenses 111 are positively correlated with the thickness of the image module.

[0063] Optionally, in some embodiments, the distribution density and curvature of the microlenses 111 are adjusted, so that parameters such as focal length can be adjusted accordingly, thereby achieving image modules 10 with different thicknesses. By way of example and not limitation, the thickness of the image module 10 can be 0.8 mm to 10 mm or 0.5 mm to 20 mm.

[0064] Optionally, in some embodiments, when performing fingerprint detection on an object to be detected, the image sensor 14 may be exposed multiple times to acquire multiple fingerprint images of the object to be detected. The multiple exposures of the image sensor 14 may have different exposure times and / or the detection light beam 101 provided by the light source 20 when the image sensor 14 is exposed may have different light intensities, so that at least part of the multiple fingerprint images have different average brightness.

[0065] Optionally, in some embodiments, the image module 10 may collect and generate K fingerprint images of the object to be detected multiple times, wherein each fingerprint image is an image with a size of M pixels*N pixels, where K, M, and N are all positive integers. At least part of the K fingerprint images has different average brightness.

[0066] In a possible embodiment, the image sensor 14 performs at least K exposures with each exposure time i (unit: milliseconds) and the time interval between adjacent exposures j (unit: milliseconds), then the time required for K exposures is: K*i+(K-1)*j (unit: milliseconds); the detection light beam emitted by the light source 20 when the image sensor 14 is exposed has different light intensities (or illumination), and the light intensity range of the detection light beam provided by the light source 20 is defined as 0 to L (unit: lux). When the image sensor 14 is exposed K times, the light intensity provided by the light source 20 can be L / K, 2L / K, 3L / K, ... (K-1)L / K, L, where 0<i, j≤1000, K≥3. Thus, the fingerprint detection device 1 can obtain K fingerprint images of the object to be detected through K exposures of the image sensor 14. The fingerprint images can have different average brightness.

[0067] In a possible embodiment, the illumination intensity range of the detection light beam provided by the light source 20 is defined as 0 to L (unit: lux), and the maximum number of continuous exposures of the image sensor 14 is P. The light source 20 can provide any one of the following illumination intensities when the image sensor 14 is exposed: L / P, 2L / P, ... (P-1)*L / P, L. When collecting the fingerprint image of the object to be detected, the actual number of exposures of the image sensor 14 can be set to K, 1≤K≤P, and K and P are both positive integers. The image sensor 14 performs at least K exposures in a manner where each exposure time is i (unit: milliseconds) and the time interval between adjacent exposures is j (unit: milliseconds). Then the time required for K exposures is: K*i+(K-1)*j (unit: milliseconds). The light source 20 provides K detection light beams with different light intensities varying from small to large when the image sensor 14 is exposed K times: L / P, 2L / P, ... K*L / P, or the light source 20 selects any K different light intensity values ​​from {L / P, 2L / P, ... (P-1)*L / P, L} when the image sensor 14 is exposed K times. Thus, the fingerprint detection device 1 can obtain K fingerprint images of the object to be detected through K exposures of the image sensor 14. The fingerprint images can have different average brightness.

[0068] In a possible embodiment, the maximum number of continuous exposures of the image sensor 14 is P, and the actual number of exposures of the image sensor 14 can be set to K, 1≤K≤P, and K and P are both positive integers. The image sensor 14 performs at least K exposures in a manner where the exposure times are i+Δt1, i+Δt2, ... i+Δt(K-1), i+ΔtK (unit: milliseconds), and the time interval between adjacent exposures is j (unit: milliseconds). The illumination intensity of the detection light beam provided by the light source 20 in the K exposures of the image sensor 14 is L0 (unit: lux). Optionally, Δt1+Δt2+...+Δt(K-1)+ΔtK=0, L0=(K2+K)*L / 2K2, K≥3, L0>0, and the time required for the K exposures of the image sensor 14 is: K*i+(K-1)*j (unit: milliseconds).

[0069] In a possible embodiment, the maximum number of continuous exposures of the image sensor 14 is P, and the actual number of exposures of the image sensor 14 can be set to K, 1≤K≤P, and K and P are both positive integers. The image sensor 14 performs at least K exposures in a manner where the exposure times are i+Δt1, i+Δt2, ... i+Δt(K-1), i+ΔtK (unit: milliseconds), and the time interval between adjacent exposures is j (unit: milliseconds). The illumination intensity range of the detection light beam provided by the light source 20 is defined as 0 to L (unit: lux), and the maximum number of continuous exposures of the image sensor 14 is P. The light source 20 can provide any one of the following illumination intensities when the image sensor 14 is exposed: L / P, 2L / P, ... (P-1)*L / P, L. When collecting the fingerprint image of the object to be detected, the actual number of exposures of the image sensor 14 can be set to K, 1≤K≤P, and K and P are both positive integers. The light source 20 provides K detection light beams with different light intensities varying from small to large when the image sensor 14 is exposed K times: L / P, 2L / P, ... K*L / P, or, the light source 20 selects any K different light intensity values ​​from {L / P, 2L / P, ... (P-1)*L / P, L} when the image sensor 14 is exposed K times. Thus, the fingerprint detection device 1 can obtain K fingerprint images of the object to be detected through K exposures of the image sensor 14. The fingerprint images can have different average brightness. Optionally, Δt1+Δt2+...+Δt(K-1)+ΔtK=0, L0=(K2+K)*L / 2K2, K≥3, L>0, and the time required for K exposures of the image sensor 14 is K*i+(K-1)*j (unit: milliseconds).

[0070] Among them, the time required for K exposures of the image sensor 14 can satisfy: 0<K*i+(K-1)*j<1000 (unit: milliseconds). Optionally, in some embodiments, the fingerprint detection device 1 also includes an ambient light sensor, which is used to detect the ambient light illumination LE above or near the field of view area VA. It can be understood that the more ambient light can penetrate the finger of the object to be detected, the more interference there is to the image sensor 14 in collecting the detection light beam returned by the finger of the object to be detected. Therefore, when the ambient light illumination is greater, the greater the number of exposures K of the image sensor 14, or the longer the single exposure time of the image sensor 14, or the greater the average light intensity of the detection light beam provided by the light source 20 within the K exposures (a possible way to calculate the average light intensity is to accumulate the light intensity of K times and divide it by K).

[0071] By repeatedly collecting and imaging the detection light beam from the finger of the object to be detected, multiple fingerprint images with different average brightness values ​​can be obtained. At least part of these fingerprint images can have good image quality for fingerprint feature detection after algorithm processing (including but not limited to interpolation, cropping, synthesis, pixel superposition, contrast, brightness and other processing). The fingerprint feature detection may include but not limited to sweat pore feature information comparison and / or texture feature information comparison, so as to have a better fingerprint feature detection effect. Of course, in other or modified embodiments, the fingerprint detection device 1 can also be used to detect palm prints or other biometric features, which is not limited in the embodiments of the present application.

[0072] Compared with the prior art, the fingerprint detection device 1 of the present application can obtain a fingerprint image of the object to be detected with better image quality by adjusting the exposure times, exposure time, exposure interval time of the image sensor 14 and the light intensity of the detection light beam emitted by the light source 20, thereby having a better fingerprint feature detection effect.

[0073] Please also read Figure 5 , is a schematic diagram of the multiple microlenses 111 converging the detection beam 101 on the image sensor 14. It can be seen that each microlens 111 converges the detection beam from a portion of the fingerprint of the finger 100 and can be used to generate a corresponding partial fingerprint image. The image sensor 14 can stitch the multiple partial fingerprint images generated by the multiple microlenses 111 into a relatively complete fingerprint image of the finger 100 through an image algorithm.

[0074] Please also read Figure 6, is a partial schematic diagram of the fingerprint image of the object to be detected. After image processing, the fingerprint image of the object to be detected has alternately spaced ridges 1001 and valleys 1002, and sweat pores 1003 located inside the ridges 1001. The sweat pores 1003 are located at intervals inside the ridges 1001, and the sweat pores 1003 and the ridges 1001 have a difference in grayscale. The sweat pores 1003 can be circular sweat pores, elliptical sweat pores, triangular sweat pores, quadrilateral sweat pores, irregular sweat pores, etc. The diameter of the sweat pores 1003 can be 50μm to 100μm, 100μm to 200μm, or 200μm to 250μm, or have a larger diameter.

[0075] Optionally, in some embodiments, the fingerprint detection device 1 includes a memory, and the memory includes a reference fingerprint image of an authorized user collected in advance. The fingerprint detection device 1 obtains the coordinates corresponding to the sweat pores 1003 of the fingerprint image of the object to be detected and the coordinates corresponding to the sweat pores of the reference fingerprint image, and compares the coordinates of the sweat pores of the two, and generates a comparison result, which can usually be represented by a matching value. The larger the matching value, the closer the characteristics of the fingerprint image of the object to be detected and the reference fingerprint image are.

[0076] It should be noted that the sweat pore coordinates mentioned here may be the center point coordinates or the center of gravity coordinates of the sweat pores.

[0077] Optionally, in some embodiments, the fingerprint detection device 1 includes a memory, and the memory includes a pre-collected reference fingerprint image of an authorized user. The fingerprint image of the object to be detected and the pre-collected reference fingerprint image can be divided into a plurality of comparison areas, each comparison area of ​​the fingerprint image of the object to be detected corresponds to a comparison area of ​​the reference fingerprint image. The fingerprint detection device 1 obtains the average grayscale value in each comparison area of ​​the fingerprint image of the object to be detected and the average grayscale value in each comparison area of ​​the reference fingerprint image, and compares the average grayscale values ​​of the corresponding comparison areas respectively.

[0078] Optionally, in some embodiments, the fingerprint detection device 1 may use sweat pore coordinates and / or sweat pore average grayscale values ​​to compare the fingerprint image of the object to be detected with a pre-collected reference fingerprint image.

[0079] Optionally, in some embodiments, the fingerprint detection device 1 obtains the average grayscale value of the ridge 1001 of the fingerprint image of the object to be detected and the sweat pores 1003 located in the ridge 1001, and obtains the average grayscale value of the ridge and the sweat pores located in the ridge of the reference fingerprint image, and compares the average grayscale values ​​of the two respectively.

[0080] Optionally, in some embodiments, the fingerprint detection device 1 obtains the average grayscale values ​​of the ridges 1001, valley lines 1002, and sweat pores 1003 of the fingerprint image of the object to be detected, as well as the average grayscale values ​​of the ridges, valley lines, and sweat pores of the reference fingerprint image, and compares the average grayscale values ​​of the ridges, valley lines, and sweat pores of the fingerprint image of the object to be detected and the pre-collected reference fingerprint image, respectively.

[0081] Optionally, in some embodiments, the fingerprint detection device 1 includes a memory, and the memory includes a reference fingerprint image of an authorized user collected in advance. The fingerprint detection device 1 obtains the average grayscale corresponding to each sweat pore 1003 of the fingerprint image of the object to be detected and the average grayscale corresponding to each sweat pore of the reference fingerprint image, and compares the average grayscale of each sweat pore of the two.

[0082] Optionally, in some embodiments, the image processing includes, for example but not limited to, using a local grayscale variance method to segment the area where the fingerprint image is located from the fingerprint image, using a directional filtering method in the extracted area to binarize the fingerprint, and refining the binary image through an OPTA algorithm or the like.

[0083] Optionally, in some embodiments, the image sensor 14 may be a CCD (Charge-coupled Device) sensor or a CMOS (Complementary Metal Oxide Semiconductor) sensor or any other light-sensitive imaging component.

[0084] Optionally, in some embodiments, the upper surface of the glass cover plate 40 has a detection area, and the detection area and the field of view (FOV) of the image sensor 14 at least partially overlap. The fingerprint detection device 1 also includes a control unit. The control unit is used to sense whether the finger 100 of the object to be detected contacts the detection area, control the light source 20 and the image module 10 to turn on when the finger 100 of the object to be detected approaches or contacts the detection area, and control the light source 20 and the image module 10 to turn off when the fingerprint detection is completed or the finger 100 of the object to be detected leaves the detection area. Further, the control unit can control the shooting frequency and frame number of the image sensor 14. In order to obtain a better fingerprint image effect, the control unit can control the luminous brightness of the light source 20, and control the image sensor 14 to shoot once or multiple times at the same brightness, or to shoot once or multiple times at different brightnesses. This is helpful for obtaining the characteristic information required for live detection by detecting blood sample concentration characteristic information, sweat pore characteristic information, etc.

[0085] See also Figure 7, is a flow chart of an embodiment of the fingerprint detection method of the present application.

[0086] The fingerprint detection method comprises:

[0087] Step S10, obtaining a fingerprint image of the object to be detected, wherein the fingerprint image shows ridges, valleys and sweat pores;

[0088] Step S20, acquiring fingerprint feature information of the object to be detected according to the fingerprint image of the object to be detected, wherein the fingerprint feature information includes sweat pore feature information and ridge valley feature information;

[0089] Step S30, performing feature information comparison between the fingerprint image and the fingerprint image of the authorized user collected in advance to obtain a feature matching value, wherein the feature information comparison includes sweat pore feature information comparison and ridge valley feature information comparison;

[0090] Step S40: determining whether the object to be detected is a living body according to the feature matching value.

[0091] Optionally, in some embodiments, the feature matching value includes a sweat pore feature matching value and a ridge valley feature matching value, and when the sweat pore feature matching value is greater than or equal to a first threshold and the ridge valley feature matching value is greater than or equal to a second threshold, the object to be detected is a living body.

[0092] Optionally, in some embodiments, the sweat pore characteristic information includes at least one of sweat pore size, sweat pore position, and sweat pore grayscale.

[0093] Optionally, in some embodiments, the ridge-valley feature information includes ridge line information and valley line information formed by alternating ridge lines and valley lines.

[0094] Optionally, in some embodiments, the fingerprint feature information also includes average grayscale information, and the average grayscale information is the average grayscale size of the sweat pores and the ridges where they are located, and the fingerprint feature comparison also includes average grayscale information comparison.

[0095] Optionally, in some embodiments, the feature matching value further includes an average grayscale matching value, and when the average grayscale matching value is greater than or equal to a third threshold, the object to be detected is a living body.

[0096] Optionally, in some embodiments, the sweat pore feature information comparison, the ridge and valley feature information comparison and the average grayscale information comparison are compared separately.

[0097] Optionally, in some embodiments, the sweat pores corresponding to the sweat pore characteristic information are displayed on the fingerprint image of the object to be detected as being completely located within the ridge line.

[0098] It should be understood that the fingerprint detection method of the present application can be applied to the fingerprint detection device 1 of the present application.

[0099] See also Figure 8 , is a block diagram of an embodiment of an electronic device of the present application. The electronic device may include a fingerprint detection device 1, a central processing unit, a display unit, a sound unit, and a power supply. The fingerprint detection device 1 may include an image module, a light source, and a control unit. The display unit may display the fingerprint detection process in real time, as well as the detection result of the fingerprint detection device 1, "verification successful" or "verification failed". The sound unit may prompt the object to be detected to place a finger, and may also emit different prompt sounds according to different detection results.

[0100] The central processing unit uses various interfaces and lines to connect various parts of the electronic device, and performs various functions and processes data by running or executing software programs and / or modules stored in the memory and calling data stored in the memory.

[0101] Optionally, in some embodiments, the fingerprint detection device 1 may include a communication unit and a microprocessor, and the communication unit 101 may be connected to the microprocessor of the fingerprint detection device 1. The communication unit may be used for receiving and sending signals during information transmission or calls. Specifically, after receiving the downlink information of the base station, it is sent to the microprocessor for processing. In addition, the uplink data is sent to the base station. Usually, the communication unit includes but is not limited to an antenna, at least one amplifier, a transceiver, a coupler, a low noise amplifier, a duplexer, etc. In addition, the communication unit 101 can also communicate with the network and other devices through wireless communication. Thus, the fingerprint detection device 1 and the electronic device including the fingerprint detection device 1 can exchange data with the remote host through the wireless communication network, and realize remote or cloud communication or remote control of the fingerprint detection device 1 and its electronic device.

[0102] Optionally, in some embodiments, the communication unit 101 may include a wireless communication module, such as but not limited to a WIFI module, a 4G module, a 5G module, a Bluetooth module, a zigbee module, etc.

[0103] Optionally, in some embodiments, the communication unit 101 may also include a wired communication module, such as a USB module, an Ethernet module, an IIS module, an HDMI module, and the like.

[0104] Of course, optionally, in some embodiments, the image module 10 may be integrated with a processing chip, and the communication unit 101 may be connected to the image module 10 and used for data communication between the image module 10 and an external device.

[0105] In some embodiments, the communication unit 101 may be connected to the central processing unit for communication with the central processing unit.

[0106] The steps in the method of the embodiment of the present application can be adjusted in order, combined and deleted according to actual needs.

[0107] The units in the device of the embodiment of the present application can be merged, divided and deleted according to actual needs.

[0108] In the present application, the same or similar terminology concepts, technical solutions and / or application scenario descriptions are generally described in detail only the first time they appear. When they appear again later, they are generally not repeated for the sake of brevity. When understanding the technical solutions and other contents of the present application, for the same or similar terminology concepts, technical solutions and / or application scenario descriptions that are not described in detail later, reference can be made to the previous related detailed descriptions.

[0109] In the present application, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0110] The various technical features of the technical solution of the present application can be arbitrarily combined. In order to make the description concise, not all possible combinations of the various technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of the present application.

[0111] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present application, or the part that contributes to the prior art, can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) as above, and includes a number of instructions for a terminal device (which can be a mobile phone, a computer, a server, a controlled terminal, or a network device, etc.) to execute the method of each embodiment of the present application.

[0112] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When loading and executing computer program instructions on a computer, the process or function according to the embodiment of the present application is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions can be transmitted from a website site, a computer, a server or a data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line) or wireless (e.g., infrared, wireless, microwave, etc.) mode to another website site, computer, server or data center. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server, a data center, etc. that contains one or more available media integrated. The available medium can be a magnetic medium, (e.g., a floppy disk, a storage disk, a tape), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., a solid-state storage disk Solid State Disk (SSD)), etc.

[0113] The above are only preferred embodiments of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A fingerprint detection device, characterized in that: include A light source, used for emitting a detection light beam to a finger of an object to be detected; An image module is used to receive the detection light beam reflected from the finger of the object to be detected and convert it into a corresponding electrical signal to generate a fingerprint image of the object to be detected, wherein the fingerprint image of the object to be detected includes sweat pore feature information and line feature information, wherein the sweat pore feature information includes the grayscale of the sweat pores located on the ridge line, and the light source is located around or below the image module; The image module includes an image sensor, a processing unit and a storage unit, wherein: The processing unit can be used to obtain the sweat pore feature information of the fingerprint image of the object to be detected. When the quantized value of the sweat pore feature information of the fingerprint image of the object to be detected is greater than or equal to a preset sweat pore feature information threshold, the processing unit obtains the texture feature information of the fingerprint image of the object to be detected, and compares the sweat pore feature information and / or texture feature information with the reference fingerprint image pre-collected and stored in the storage unit to confirm whether the object to be detected is a live authorized user; or: the processing unit obtains the sweat pore feature information and texture feature information of the fingerprint image of the object to be detected, and compares them with the reference fingerprint image pre-collected and stored in the storage unit to confirm whether the object to be detected is a live authorized user; The image sensor is exposed multiple times to acquire fingerprint images of multiple objects to be detected. The multiple exposures of the image sensor have different exposure times and / or the light source provides detection light beams with different light intensities when the image sensor is exposed, so that at least some of the fingerprint images of the multiple objects to be detected have different average brightness.

2. The fingerprint detection device according to claim 1, characterized in that: It also includes a glass cover plate, which is located above the light source and the image module. The detection light beam passes through the glass cover plate and irradiates the finger of the object to be detected. After being reflected on the finger of the object to be detected, the detection light beam passes through the glass cover plate and is received by the image module and converted into a corresponding electrical signal.

3. The fingerprint detection device according to claim 2, characterized in that: The upper surface of the glass cover plate has a detection area, and the fingerprint detection device also includes a control unit, which is used to sense whether the finger of the object to be detected contacts the detection area, control the light source and the image module to turn on when the finger of the object to be detected approaches or contacts the detection area, and control the light source and the image module to turn off when the fingerprint detection is completed or the finger of the object to be detected leaves the detection area.

4. The fingerprint detection device according to claim 1, characterized in that: The fingerprint detection device is configured to distinguish the sweat pores in the fingerprint image by virtue of the refractive index of sweat being lower than the refractive index of the skin of the finger.

5. The fingerprint detection device according to claim 1, characterized in that: The image module includes an image sensor for receiving a detection light beam and converting it into an electrical signal, the image sensor includes a substrate, a pixel array located on the substrate, and a microlens array located above the pixel array; the microlens array includes a plurality of microlenses arranged in an array, the pixel array includes a plurality of pixel units arranged in an array, wherein each of the microlenses corresponds to a plurality of the pixel units, and the focal length of the microlenses and the distribution density of the microlenses are positively correlated with the thickness of the image module.

6. The fingerprint detection device according to claim 5, characterized in that: The substrate has a plurality of grooves opened on a side or around the pixel array, the light source includes a plurality of light-emitting units, at least part of the light-emitting units are arranged in the plurality of grooves, and the light-emitting units arranged in the grooves are top-emitting type; or: The light source includes a plurality of light emitting units, and the plurality of light emitting units are dispersedly arranged around the image module, and at least part of the plurality of light emitting units are of side emitting type or top emitting type.

7. The fingerprint detection device according to claim 1, characterized in that: The detection light beam is visible light, and the visible light includes green light; or the detection light beam includes invisible light, and the invisible light includes infrared light or near-infrared light.

8. A fingerprint detection method, characterized in that: include: Acquire a plurality of fingerprint images of objects to be detected, wherein the fingerprint images of the plurality of objects to be detected have different average brightnesses, and the fingerprint images display ridges, valleys, and sweat pores; Acquire fingerprint feature information of the object to be detected according to the fingerprint image of the object to be detected, the fingerprint feature information includes sweat pore feature information and grain feature information, the grain feature information includes ridge and valley feature information, and the sweat pore feature information includes the grayscale of sweat pores located on the ridge line; Performing feature information comparison between the fingerprint image and a reference fingerprint image of an authorized user collected in advance to obtain a feature matching value, wherein the feature information comparison includes sweat pore feature information comparison and / or texture feature information comparison, wherein when the quantized value of the sweat pore feature information of the fingerprint image of the object to be detected is greater than or equal to a preset sweat pore feature information threshold, obtaining the texture feature information of the fingerprint image of the object to be detected, and performing sweat pore feature information comparison and / or texture feature information comparison with the reference fingerprint image collected in advance and stored in the storage unit to obtain the feature matching value; or, obtaining the sweat pore feature information and texture feature information of the fingerprint image of the object to be detected, and comparing them with the reference fingerprint image collected in advance and stored in the storage unit to obtain the feature matching value; It is determined whether the object to be detected is a live authorized user according to the feature matching value.

9. The fingerprint detection method according to claim 8, characterized in that: The feature matching value includes a sweat pore feature matching value and a ridge valley feature matching value. When the sweat pore feature matching value is greater than or equal to a first threshold and the ridge valley feature matching value is greater than or equal to a second threshold, the object to be detected is a living body.

10. The fingerprint detection method according to claim 8, characterized in that: The sweat pore characteristic information includes sweat pore size.

11. The fingerprint detection method according to claim 8, characterized in that: The ridge-valley feature information includes ridge line information and valley line information formed by alternating ridge lines and valley lines.

12. The fingerprint detection method according to claim 8, characterized in that: The fingerprint feature information also includes average grayscale information, and the average grayscale information is the average grayscale size of the sweat pores and the ridges where they are located. The fingerprint feature comparison also includes average grayscale information comparison.

13. The fingerprint detection method according to claim 12, characterized in that: The feature matching value also includes an average grayscale matching value. When the average grayscale matching value is greater than or equal to a third threshold, the object to be detected is a living body.

14. The fingerprint detection method according to claim 12, characterized in that: The sweat pore characteristic information comparison, the ridge and valley characteristic information comparison and the average grayscale information comparison are compared separately.

15. The fingerprint detection method according to claim 8, characterized in that: The sweat pores corresponding to the sweat pore characteristic information are displayed on the fingerprint image of the object to be detected as being completely located within the ridge line.

16. An electronic device, characterized in that: The electronic device comprises the fingerprint detection device as claimed in any one of claims 1 to 7.

Images