Fingerprint unlocking method and device, electronic equipment and storage medium

Abstract

This disclosure relates to a fingerprint unlocking method, apparatus, electronic device, and storage medium. The fingerprint unlocking method includes: acquiring a fingerprint image using an optical fingerprint sensor of the electronic device when a user unlocks the device with their fingerprint; performing fingerprint unfolding processing on the fingerprint image according to a preset curvature to obtain an unfolded fingerprint image; and unlocking the electronic device if the unfolded fingerprint image matches a preset fingerprint image. This disclosure ensures the security of fingerprint unlocking while improving its speed by introducing a preset curvature to unfold the fingerprint image acquired by the optical fingerprint sensor and verifying the fingerprint unlock using the unfolded fingerprint image.

Description

Technical Field

[0001] This disclosure relates to the field of liquid crystal display, and more particularly to a fingerprint unlocking method, device, electronic device, and storage medium. Background Technology

[0002] With the continuous development of fingerprint verification technology, more and more electronic devices can be unlocked by fingerprint. Typically, the fingerprint sensor installed in electronic devices can recognize and verify the user's fingerprint. After successful verification, the device is unlocked, allowing the user to operate the electronic device, thereby preventing strangers from operating the device and ensuring its security.

[0003] In related technologies, fingerprint sensors have evolved into optical fingerprint sensors. With optical fingerprint sensors, users do not need to press their fingers completely onto the screen of electronic devices. By shining light on the fingerprint and collecting the light reflected from the fingerprint, a planar fingerprint image can be obtained. Summary of the Invention

[0004] To overcome the problems existing in related technologies, this disclosure provides a fingerprint unlocking method, device, electronic device, and storage medium.

[0005] According to a first aspect of the present disclosure, a fingerprint unlocking method is provided, comprising:

[0006] When a user unlocks an electronic device with their fingerprint, the fingerprint image is acquired through the electronic device's optical fingerprint sensor.

[0007] The fingerprint image is unfolded according to a preset curvature to obtain the unfolded fingerprint image.

[0008] If the unfolded fingerprint image matches the preset fingerprint image, the electronic device is unlocked.

[0009] Optionally, a fingerprint image is acquired via an optical fingerprint sensor of an electronic device, including:

[0010] Acquire contact information between the user's finger and the screen of the electronic device;

[0011] If the contact information meets the preset conditions, the fingerprint image is acquired through the optical fingerprint sensor of the electronic device.

[0012] Optionally, the contact information includes the contact area, and before acquiring a fingerprint image via the optical fingerprint sensor of the electronic device if the contact information meets preset conditions, it also includes:

[0013] If the contact area is greater than or equal to the area threshold, the contact information is determined to meet the preset conditions, wherein the area threshold is less than the contact area when the user's finger is in full contact with the screen.

[0014] Optionally, the contact information also includes the contact duration, and before acquiring a fingerprint image via the optical fingerprint sensor of the electronic device if the contact information meets preset conditions, it also includes:

[0015] If the contact area is greater than or equal to the area threshold and the contact duration is greater than or equal to the duration threshold, then the contact information is determined to meet the preset conditions.

[0016] Optionally, the fingerprint image is unfolded according to a preset curvature to obtain an unfolded fingerprint image, including:

[0017] Based on the preset curvature and Mercator algorithm, the fingerprint image is unfolded to obtain the unfolded fingerprint image.

[0018] Optionally, the fingerprint image is unfolded according to a preset curvature and Mercator algorithm to obtain an unfolded fingerprint image, including:

[0019] Obtain the coordinate information of the fingerprint image in a preset rectangular coordinate system, which is pre-established on the screen of the electronic device;

[0020] Substitute the coordinate information and preset curvature into the Mercator projection back solution formula for calculation to obtain the longitude and latitude corresponding to the coordinate information;

[0021] The unfolded fingerprint image is constructed based on latitude and longitude.

[0022] Optionally, if the unfolded fingerprint image matches a preset fingerprint image, the electronic device is unlocked, including:

[0023] Obtain the deformation between the fingerprint image and the unfolded fingerprint image;

[0024] If the deformation meets the preset deformation conditions, then determine whether the unfolded fingerprint image matches the preset fingerprint image;

[0025] If the unfolded fingerprint image matches the preset fingerprint image, the electronic device is unlocked.

[0026] Optionally, before performing fingerprint unfolding processing on the fingerprint image according to a preset curvature to obtain the unfolded fingerprint image, the method further includes:

[0027] Multiple sample fingerprint images of the user are acquired using an optical fingerprint sensor;

[0028] Obtain the curvature corresponding to each fingerprint image sample to obtain multiple sample curvatures;

[0029] The mean curvature of multiple samples is calculated, and the calculation result is determined as the preset curvature.

[0030] Optionally, before performing fingerprint unfolding processing on the fingerprint image according to a preset curvature to obtain the unfolded fingerprint image, the method further includes:

[0031] Identify user identity information;

[0032] The curvature corresponding to the identity information is obtained from the curvature database as the preset curvature.

[0033] Optionally, the preset fingerprint image is obtained in the following way:

[0034] When a user registers their fingerprint on an electronic device, the fingerprint image is acquired through the electronic device's optical fingerprint sensor.

[0035] The fingerprint image is unfolded according to a preset curvature to obtain the unfolded fingerprint image.

[0036] The unfolded fingerprint image is stored as a preset fingerprint image in the electronic device.

[0037] According to a second aspect of the present disclosure, a fingerprint unlocking device is provided, comprising:

[0038] The fingerprint image acquisition module is configured to acquire a fingerprint image through the optical fingerprint sensor of the electronic device when the user unlocks the electronic device with his / her fingerprint.

[0039] The unfolding module is configured to perform fingerprint unfolding processing on the fingerprint image according to a preset curvature to obtain the unfolded fingerprint image;

[0040] The unlocking module is configured to unlock the electronic device when the unfolded fingerprint image matches a preset fingerprint image.

[0041] Optionally, the fingerprint image acquisition module includes:

[0042] The contact information acquisition submodule is configured to acquire contact information between the user's finger and the screen of the electronic device;

[0043] The fingerprint image acquisition submodule is configured to acquire a fingerprint image through the optical fingerprint sensor of the electronic device when the contact information meets preset conditions.

[0044] Optionally, the contact information includes the contact area, and the fingerprint image acquisition module also includes:

[0045] The first judgment submodule determines that the contact information meets the preset conditions when the contact area is greater than or equal to the area threshold, wherein the area threshold is less than the contact area when the user's finger is in full contact with the screen.

[0046] Optionally, the contact information also includes contact duration. The fingerprint image acquisition module also includes:

[0047] The second judgment submodule is configured to determine that the contact information meets the preset conditions when the contact area is greater than or equal to the area threshold and the contact duration is greater than or equal to the duration threshold.

[0048] Optionally, the expanded module is specifically configured as follows:

[0049] Based on the preset curvature and Mercator algorithm, the fingerprint image is unfolded to obtain the unfolded fingerprint image.

[0050] Optionally, the unfolding module includes:

[0051] The coordinate information submodule is configured to acquire coordinate information in a preset rectangular coordinate system corresponding to the fingerprint image, and the preset rectangular coordinate system is pre-established on the screen of the electronic device;

[0052] The calculation submodule is configured to substitute the coordinate information and the preset curvature into the Mercator projection back solution formula for calculation to obtain the longitude and latitude corresponding to the coordinate information;

[0053] A construction submodule is configured to construct the unfolded fingerprint image based on the latitude and longitude.

[0054] Optional unlocking modules include:

[0055] The deformation acquisition submodule is configured to acquire the deformation between the fingerprint image and the unfolded fingerprint image;

[0056] The judgment submodule is configured to determine whether the unfolded fingerprint image matches the preset fingerprint image when the shape and variable meet the preset shape and variable conditions;

[0057] The unlocking submodule is configured to unlock the electronic device when the unfolded fingerprint image matches a preset fingerprint image.

[0058] Optionally, the fingerprint unlocking device further includes a preset curvature determination module, which is configured to: acquire multiple sample fingerprint images of the user through an optical fingerprint sensor; acquire the curvature corresponding to each sample fingerprint image to obtain multiple sample curvatures; calculate the average of the multiple sample curvatures and determine the calculation result as the preset curvature.

[0059] Optionally, the preset curvature determination module is further configured to: identify the user's identity information; and obtain the curvature corresponding to the identity information from the curvature database as the preset curvature.

[0060] Optionally, the fingerprint unlocking device also includes an enrollment module, which is configured to:

[0061] When a user registers their fingerprint on an electronic device, the fingerprint image is acquired through the electronic device's optical fingerprint sensor.

[0062] The fingerprint image is unfolded according to a preset curvature to obtain the unfolded fingerprint image.

[0063] The unfolded fingerprint image is stored as a preset fingerprint image in the electronic device.

[0064] According to a third aspect of the present disclosure, an electronic device is provided, comprising: a processor; a memory for storing processor-executable instructions; and an optical fingerprint sensor for acquiring fingerprint images; wherein the processor is configured to:

[0065] When a user unlocks an electronic device with their fingerprint, the system controls the electronic device's optical fingerprint sensor to acquire a fingerprint image; it then performs fingerprint unfolding processing on the fingerprint image according to a preset curvature to obtain an unfolded fingerprint image; and finally, when the unfolded fingerprint image matches a preset fingerprint image, the electronic device is unlocked.

[0066] According to a fourth aspect of the present disclosure, a computer-readable storage medium is provided that stores computer program instructions thereon, which, when executed by a processor, implement the steps of the fingerprint unlocking method provided in the first aspect of the present disclosure.

[0067] The technical solutions provided by the embodiments of this disclosure can include the following beneficial effects: when a user unlocks an electronic device with their fingerprint, a fingerprint image is acquired through the optical fingerprint sensor of the electronic device, and the fingerprint image is unfolded according to a preset curvature to obtain an unfolded fingerprint image. If the unfolded fingerprint image matches the preset fingerprint image, the electronic device is unlocked. Since a curvature parameter is introduced into the unfolding based on the two-dimensional planar fingerprint image, this unfolded fingerprint image can be regarded as a spherical unfolding of the three-dimensional curved surface of the fingerprint, possessing unique deformations that are difficult to counterfeit from planar fingerprints. Therefore, the unfolded fingerprint image has high anti-counterfeiting capabilities, and unlocking security can be guaranteed by verifying the unfolded fingerprint image.

[0068] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this disclosure. Attached Figure Description

[0069] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure.

[0070] Figure 1 This is a schematic diagram illustrating the application environment of a fingerprint unlocking method according to an exemplary embodiment.

[0071] Figure 2 This is a schematic diagram of the structure of an under-display fingerprint recognition module according to an exemplary embodiment.

[0072] Figure 3 This is a flowchart illustrating a fingerprint unlocking method according to an exemplary embodiment.

[0073] Figure 4 This is a flowchart illustrating a fingerprint unlocking method according to another exemplary embodiment.

[0074] Figure 5 This is a schematic diagram illustrating the fingerprint image recording process according to an exemplary embodiment.

[0075] Figure 6 This is a schematic diagram illustrating the principle of unfolding a fingerprint image through a Mercator cylinder according to an exemplary embodiment.

[0076] Figure 7 It is based on Figure 4 The embodiment shows a flowchart of one implementation of step S203.

[0077] Figure 8 It is based on Figure 4 A flowchart illustrating another implementation of step S203 in the embodiment.

[0078] Figure 9 It is based on Figure 4 The embodiment shows a flowchart of one implementation of step S204.

[0079] Figure 10 This is a schematic diagram illustrating the unfolding of a two-dimensional planar fingerprint image and a three-dimensional fingerprint image according to an exemplary embodiment.

[0080] Figure 11 This is a block diagram illustrating a fingerprint unlocking device according to an exemplary embodiment.

[0081] Figure 12 This is a block diagram illustrating an electronic device according to an exemplary embodiment. Detailed Implementation

[0082] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numerals in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this disclosure. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this disclosure as detailed in the appended claims.

[0083] As fingerprint technology becomes more widely used, fingerprint unlocking technology is also developing rapidly. Among them, optical fingerprint sensors are gradually replacing traditional capacitive sensors. Compared with capacitive sensors, optical fingerprint sensors do not require users to press their fingers on a large area of ​​the fingerprint collection area. They only need to shine light on the fingerprint and receive the projection of the light reflected back from the fingerprint on the fingerprint collection area to generate a fingerprint image. Therefore, it avoids the process of users pressing the fingerprint collection area for a long time and a large area, thus significantly shortening the fingerprint collection time and improving the user experience.

[0084] However, in related technologies, the planar fingerprint image captured by optical fingerprint sensors is an image of the user's fingerprint directly projected onto the screen of an electronic device, essentially treating the user's fingerprint as a purely planar image. But a human finger is not a perfectly flat plane; the fingertip is a spherical curved surface. This spherical surface can be unfolded in a specific way, and the resulting fingerprint image is equivalent to the fingerprint image captured by a traditional capacitive fingerprint sensor. The unfolded fingerprint image is not the same as the purely planar image captured by an optical fingerprint sensor. Compared to the unfolded fingerprint image, a purely planar image is easier to illegally capture and copy, thus compromising the security of fingerprint unlocking.

[0085] In view of this, the present disclosure provides a fingerprint unlocking method, apparatus, electronic device and storage medium, which expands the fingerprint image by introducing a preset curvature based on the fingerprint image collected by the optical fingerprint sensor, and verifies the fingerprint unlocking by using the expanded fingerprint image, thereby ensuring the security of fingerprint unlocking and improving the speed of fingerprint unlocking.

[0086] The following describes the application environment of the fingerprint unlocking method provided in this disclosure, such as... Figure 1 As shown, this fingerprint unlocking method can be applied to electronic device 100. Specifically, the electronic device 100 can be a smartphone. The electronic device 100 can be configured with an under-display fingerprint recognition module 110 and a processor (not shown in the figure). The under-display fingerprint recognition module 110 is used to collect the user's fingerprint image. The processor can control the under-display fingerprint recognition module 110, process the fingerprint image collected by the under-display fingerprint recognition module 110, and unlock the electronic device 100, etc.

[0087] like Figure 2As shown, the under-display fingerprint recognition module 110 may include: a light source device 113, an optical fingerprint sensor 114, CG glass 111, an OLED screen 112, and a fingerprint module reinforcing steel sheet 115. The CG glass 111 can be disposed on the upper layer of the OLED screen 112 and is used for contact with the user's finger. The light source device 113 can be built into the OLED screen 112 and is configured to form a light spot to illuminate the finger touching the screen. The optical fingerprint sensor 114 can be disposed on the fingerprint module reinforcing steel sheet 115 and is used to receive the light reflected back from the finger to form a fingerprint image. The fingerprint module reinforcing steel sheet 115 can be fixed to the overall frame 120 of the electronic device.

[0088] In this case, the area of ​​the screen of the electronic device 100 corresponding to the under-display fingerprint recognition module 110 can be used as the fingerprint collection area.

[0089] Figure 3 This is a flowchart illustrating a fingerprint unlocking method according to an exemplary embodiment, such as... Figure 3 As shown, this fingerprint unlocking method can be used for, for example Figure 1 The electronic device 100 shown includes the following steps.

[0090] In step S101, when the user unlocks the electronic device with their fingerprint, a fingerprint image is acquired through the optical fingerprint sensor of the electronic device.

[0091] The fingerprint image can be an image that includes fingerprint lines.

[0092] In some implementations, when an electronic device detects that a user's finger touches the fingerprint collection area on the screen, it can determine that the user needs to unlock the device with their fingerprint. At this time, a light source is activated to emit light, forming a light spot. The light from this spot illuminates the fingerprint and is reflected from the fingerprint to an optical fingerprint sensor. The reflected light is then collected by the optical fingerprint sensor to form a fingerprint image.

[0093] In step S102, the fingerprint image is unfolded according to a preset curvature to obtain the unfolded fingerprint image.

[0094] The preset curvature can be the curvature of the user's finger that has been measured in advance. Since the fingertip can be regarded as a curved surface, it has a certain curvature.

[0095] It is understandable that, since fingerprints are distributed on the curved surface of the finger, if the curvature of the surface changes, the deformation of the fingerprints on the surface will also change after it is unfolded into a plane, which in turn will change the formed fingerprint image.

[0096] In some implementations, the preset curvature can be pre-measured on the user's finger and stored in the local memory of the electronic device. After acquiring the fingerprint image, the electronic device can retrieve the preset curvature from the local memory to perform fingerprint unfolding processing on the fingerprint image, thereby obtaining the unfolded fingerprint image. Specifically, the unfolding method can employ the Mercator two-dimensional unfolding method. For example, the Mercator two-dimensional unfolding method can refer to the unfolding method using the Earth as an example. Specifically, it is assumed that the Earth is enclosed in a hollow cylinder, with its baseline latitude line tangent to the cylinder (contacting the equator). Then, it is imagined that there is a lamp at the center of the Earth, projecting the image on the sphere onto the cylinder, and then unfolding the cylinder.

[0097] In step S103, if the unfolded fingerprint image matches the preset fingerprint image, the electronic device is unlocked.

[0098] The preset fingerprint image can be a fingerprint image that the user registered before unlocking the device. This fingerprint image is also obtained by the optical fingerprint sensor after being collected and then processed by the preset curvature to unfold the fingerprint image.

[0099] In some implementations, a preset fingerprint image can be pre-recorded in the local memory of the electronic device. After obtaining the unfolded fingerprint image, the electronic device can retrieve the preset fingerprint image from its memory and compare the unfolded fingerprint image with the preset fingerprint image. If the comparison result shows that the unfolded fingerprint image matches the preset fingerprint image, it is determined that the unfolded fingerprint image matches the preset fingerprint image, and the electronic device is unlocked.

[0100] Optionally, the preset curvature and preset fingerprint image can also be pre-stored in a cloud server that communicates with the electronic device. The electronic device can send a request to the cloud server to instruct the cloud server to provide the preset curvature and preset fingerprint image.

[0101] In this embodiment, when a user unlocks an electronic device with their fingerprint, the optical fingerprint sensor of the electronic device acquires a fingerprint image, and the fingerprint image is unfolded according to a preset curvature to obtain an unfolded fingerprint image. If the unfolded fingerprint image matches the preset fingerprint image, the electronic device is unlocked. Thus, a curvature parameter is introduced into the unfolding process based on the two-dimensional planar fingerprint image. This unfolded fingerprint image can be seen as a spherical unfolding of the three-dimensional curved surface of the fingerprint, possessing unique deformations that are difficult to imitate from planar fingerprints. Therefore, the unfolded fingerprint image has high anti-counterfeiting capabilities, and unlocking security can be guaranteed by using the unfolded fingerprint image for verification. Furthermore, compared to traditional capacitive fingerprint sensors, users do not need to press a large area of ​​their finger onto the screen for fingerprint recognition; only partial contact is required, shortening the fingerprint unlocking time and improving the user experience.

[0102] Figure 4 This is a flowchart illustrating a fingerprint unlocking method according to another exemplary embodiment, such as... Figure 4 As shown, the fingerprint unlocking method used in the aforementioned electronic device includes the following steps.

[0103] In step S201, when the user unlocks the electronic device with their fingerprint, the contact information between the user's finger and the screen of the electronic device is obtained.

[0104] In some implementations, the electronic device can determine that a user is unlocking the device with their fingerprint when it detects that the pressure on the fingerprint acquisition area exceeds a pressure threshold, and then detect the contact information between the user's finger and the screen of the electronic device. Optionally, the contact information may include contact area, contact duration, contact pressure, etc.

[0105] For example, the fingerprint acquisition area of ​​an electronic device can be configured with a pressure sensor to detect the contact force. The processor of the electronic device can start timing when the contact force exceeds a pressure threshold, and calculate the contact duration based on the duration the contact force exceeds the pressure threshold.

[0106] For example, the fingerprint collection area of ​​an electronic device is configured with a distance sensor array. This distance sensor array can be used to collect the distance between the user's fingerprint surface and the screen of the electronic device. The electronic device can use distance sensors in the distance sensor array that detect a distance less than a distance threshold as target distance sensors, and use the area formed by the target sensors as the contact area. As an example, the distance sensor array may include distance sensors 1, 2, 3...10 evenly distributed on the screen of the electronic device. If distance sensors 2 to 5 in the distance sensor array detect a distance less than the distance threshold, the area enclosed by distance sensors 2 to 5 on the screen can be used as the contact area.

[0107] In step S202, if the contact information meets the preset conditions, the fingerprint image is acquired by the optical fingerprint sensor of the electronic device.

[0108] The preset conditions are used to determine whether the user's current finger touch is a valid touch. If the touch information meets the preset conditions, the user's current finger touch is determined to be a valid touch. At this time, the electronic device can activate the optical fingerprint sensor and collect fingerprint information through the optical fingerprint sensor.

[0109] In some implementations, the contact information includes the contact area, and specific implementations of step S202 may include:

[0110] If the contact area is greater than or equal to an area threshold, the contact information is determined to meet preset conditions, where the area threshold is less than the contact area when the user's finger is in full contact with the screen. If the electronic device detects that the contact information meets the preset conditions, it activates the optical fingerprint sensor to acquire the fingerprint image of the user's finger.

[0111] The area threshold can be pre-stored in the memory of the electronic device. The electronic device can retrieve the area threshold from the memory and compare the obtained contact area with the area threshold. If the contact area is greater than or equal to the area threshold, it can be determined that the contact information meets the preset conditions.

[0112] It is understandable that the contact area when a user's finger is fully in contact with the screen can be regarded as the maximum area that the user's finger can contact when pressing on the screen.

[0113] Optionally, the area threshold can be equal to the maximum area multiplied by a specified percentage, which cannot exceed 100%. Optionally, the specified percentage can be less than or equal to 50%. For example, the area threshold can be 50%, 30%, 10%, etc. of the maximum area, and the specific specified percentage is not limited here.

[0114] In this embodiment, by determining that the contact information meets preset conditions when the contact area is greater than or equal to an area threshold, it is possible to ensure that the user's touch is a valid touch, thus preventing the user from accidentally activating the optical fingerprint sensor due to touching the screen of the electronic device. Furthermore, the area threshold is less than the maximum area that the user's finger can contact the screen when pressed, specifically less than 50% of the maximum area. This reduces the triggering difficulty of the optical fingerprint sensor, avoiding the need for the user to press the screen over a large area for a long time, thereby improving the speed and efficiency of fingerprint image acquisition.

[0115] In other embodiments, the contact information also includes the contact duration, and specific implementations of step S202 may include:

[0116] If the contact area is greater than or equal to the area threshold and the contact duration is greater than or equal to the duration threshold, then the contact information is determined to meet the preset conditions.

[0117] For example, an electronic device can start timing when the contact area between a user's finger and the screen is greater than or equal to an area threshold, thereby obtaining the contact duration. When the contact duration is greater than or equal to the duration threshold, it can be determined that the contact information meets preset conditions. If, during the timing process, the contact area changes and becomes less than the area threshold, it is determined that the contact information does not meet the preset conditions.

[0118] Considering that the user's touch time is short and is likely due to accidental touch, in this embodiment, when the contact area is greater than or equal to the area threshold and the contact time is greater than or equal to the time threshold, the contact information is determined to meet the preset conditions, thereby further ensuring that the user's touch is a valid touch and avoiding the waste of power caused by the optical fingerprint sensor being turned on due to accidental touch.

[0119] It is understood that, in this embodiment, the contact area between the user's finger and the screen refers to the contact area between the screen and the finger corresponding to the fingerprint collection area.

[0120] In step S203, the fingerprint image is unfolded according to a preset curvature to obtain the unfolded fingerprint image.

[0121] In some implementations, step S203 may include: performing fingerprint unfolding processing on the fingerprint image according to a preset curvature and Mercator algorithm to obtain an unfolded fingerprint image.

[0122] As an example, the unfolding process can be specifically as follows: The electronic device acquires the coordinate information of the fingerprint image in a preset Cartesian coordinate system, which is pre-established on the screen of the electronic device. When the user's fingerprint is projected onto the screen, since a Cartesian coordinate system is pre-established on the screen, the optical fingerprint sensor obtains the coordinate information of the point projected onto the screen by mapping it to the Cartesian coordinate system. Then, the coordinate information and the preset curvature are substituted into the Mercator projection formula for calculation to obtain the longitude and latitude corresponding to the coordinate information, i.e., the unfolded latitude and longitude. Finally, the unfolded fingerprint image is constructed based on the unfolded latitude and longitude; the construction process is equivalent to building a planar map based on the latitude and longitude of the Earth.

[0123] Specifically, a fingerprint image can be expanded using the Mercator projection formula as follows:

[0124]

[0125]

[0126] Where B is the latitude of the unfolded fingerprint image, L is the longitude of the unfolded fingerprint image, X is the horizontal coordinate of the fingerprint in the pre-constructed Cartesian coordinate system on the electronic device screen, Y is the vertical coordinate of the fingerprint in the pre-constructed Cartesian coordinate system on the electronic device screen, e is the eccentricity, B0 is the initial latitude value, i.e., the origin latitude, L0 is the initial longitude value, i.e., the origin longitude, K is the preset curvature, and EXP is the natural logarithmic base.

[0127] As an example, the fingerprint image acquisition process can be as follows: Figure 5As shown, when a finger touches the screen of the electronic device 100, specifically the under-display fingerprint recognition module 110 (i.e., the fingerprint acquisition area), the electronic device can activate the optical fingerprint sensor of the under-display fingerprint recognition module 110 to acquire a fingerprint image. The activation of the optical fingerprint sensor does not require the fingertip to completely cover the fingerprint acquisition area; as long as the contact area between the finger and the screen is greater than an area threshold, the fingerprint image acquisition function of the optical fingerprint sensor can be activated. During fingerprint image acquisition, the part of the finger in contact with the screen can be defined as the equatorial region, and the part of the finger not in contact with the screen (i.e., the non-contact part) can be defined as the low-latitude region and the high-latitude region. Due to the spherical curvature of the fingertip, the distance between the finger and the screen detected by the distance sensor can be used to define the low-latitude and high-latitude regions. Specifically, the area close to the distance sensor is defined as the low-latitude region, for example, the area where the distance sensor detects that the distance between the finger and the screen is less than or equal to a first distance threshold. Conversely, the area far from the distance sensor is defined as the high-latitude region, for example, the area where the distance sensor detects that the distance between the finger and the screen is greater than a second distance threshold, where the first distance threshold is less than or equal to the second distance threshold. Since the longitude and latitude of the collected fingerprint image are defined, and the horizontal and vertical coordinates of the screen can be predefined, the Mercator expansion can be performed using the above formula to obtain the expanded fingerprint image.

[0128] The principle behind Mercator cylinder unfolding of fingerprint images can be described as follows: Figure 6 As shown, before unfolding, a cylinder surrounds the finger, and then the spherical surface of the finger can be unfolded using the side of the cylinder. Specifically, corresponding meridians and parallels are set on the spherical surface of the finger. The position where the center of the fingertip protrudes and is tangent to the side of the cylinder is the equatorial region. Due to the spherical surface characteristics of the fingertip, the direction away from the fingertip will be further away from the side of the cylinder, and the latitude of the further away the region is, the higher the latitude. According to the above formula, the size deformation of the equatorial region is the smallest, and the deformation of the region with higher latitude is greater. Finally, the fingerprint image obtained after unfolding using the preset curvature and Mercator algorithm can be as follows: Figure 6 The fingerprint image, when unfolded, can be represented by meridians and parallels. The deformation of the unfolded fingerprint image due to these different latitudes can serve as an anti-counterfeiting design element in the fingerprint unlocking method of this embodiment. The curvature can be set by an algorithm and adjusted arbitrarily within a certain range. A greater curvature results in a larger deformation of the fingerprint image at the same latitude. These changes can only be produced when a finger with a certain spherical curvature is pressed; a planar fingerprint image cannot produce this distinction between high and low latitudes. Therefore, this effectively increases the difficulty of anti-counterfeiting and improves the security of fingerprint unlocking.

[0129] In some implementations, such as Figure 7As shown, the preset curvature in step S203 can be obtained in the following way:

[0130] Step S2031a: Acquire multiple sample fingerprint images of the user using an optical fingerprint sensor.

[0131] For example, during the fingerprint enrollment phase of an electronic device, the electronic device can guide the user to enroll their fingerprint multiple times through a preset fingerprint enrollment interface, thereby obtaining multiple sample fingerprint images of the user through an optical fingerprint sensor.

[0132] Step S2032a: Obtain the curvature corresponding to each sample fingerprint image to obtain multiple sample curvatures.

[0133] For example, an electronic device may be pre-configured with a curvature database, which may include multiple standard fingerprint images and mapping relationships between multiple sample curvatures and the multiple standard fingerprint images. For example, the mapping relationship table between multiple sample curvatures and multiple standard fingerprint images may be as shown in Table 1:

[0134] Table 1

[0135] Standard fingerprint image Sample curvature Standard fingerprint image a Sample curvature a Standard fingerprint image b Sample curvature b Standard fingerprint image c Sample curvature c

[0136] The electronic device can compare the similarity of each sample fingerprint image with multiple standard fingerprint images, find the standard fingerprint image that matches each sample fingerprint image, and determine the sample curvature corresponding to the standard fingerprint image that matches it as the sample curvature corresponding to the sample fingerprint image.

[0137] For example, if the similarity between sample fingerprint image a and standard fingerprint image b is greater than a similarity threshold, then sample fingerprint image a can be determined to match standard fingerprint image b, and the sample curvature b corresponding to standard fingerprint image b can be determined as the sample curvature corresponding to sample fingerprint image a. Similarly, the sample curvature corresponding to each sample fingerprint image can be found in the product function curvature database using the above method.

[0138] Step S2033a: Calculate the mean of the curvature of multiple samples and determine the calculation result as the preset curvature.

[0139] For example, if multiple sample curvatures include sample curvature a, sample curvature b, and sample curvature c, the sum of sample curvature a, sample curvature b, and sample curvature c can be calculated and then divided by 3 to obtain the mean of sample curvature a, sample curvature b, and sample curvature c, and this mean can be determined as the preset curvature.

[0140] Considering that users' fingers vary in thickness, the curvature of the finger surface also varies. In this embodiment, multiple sample fingerprint images of the user are acquired by an optical fingerprint sensor, and the curvature corresponding to each sample fingerprint image is obtained to obtain multiple sample curvatures. Then, the average value of multiple sample curvatures is calculated, and the calculation result is determined as the preset curvature. In this way, a unique curvature can be accurately and automatically matched for the user as the preset curvature, which improves the efficiency of setting the preset curvature and enhances the user experience.

[0141] In other implementations, such as Figure 8 As shown, the preset curvature in step S203 can be obtained in the following way:

[0142] Step S2031b: Identify the user's identity information.

[0143] For example, an electronic device can acquire a user's characteristics to identify the user's identity. Optionally, user characteristics may include facial features, voiceprint features, iris features, etc. As another example, an electronic device can determine a user's identity information based on the account information entered by the user, such as the user's ID card number, phone number, social media account, etc.

[0144] Optionally, the electronic device can determine a user's identity information using one or more of the methods mentioned above. For example, the electronic device can obtain the social media account and password entered by user A. If the social media account and password match, the identity information can be confirmed as user A. As another example, the electronic device can perform SMS verification based on the phone number entered by user B. After successful SMS verification, it can obtain user B's facial features. If facial feature verification confirms the identity as user B, the identity information can be confirmed as user B.

[0145] Step S2032b: Obtain the curvature corresponding to the identity information from the curvature database as the preset curvature.

[0146] For example, an electronic device can be pre-configured with a curvature database, which includes mapping relationships between multiple identity information and multiple curvatures. Specifically, the mapping relationships between multiple identity information and multiple curvatures can be as shown in Table 2.

[0147] Table 2

[0148]

[0149]

[0150] As can be seen, the electronic device can find the curvature corresponding to the identity information based on the currently acquired user's identity information and Table 2 in the curvature database. For example, if the electronic device recognizes that the identity information of the currently unlocked user is user A, then curvature A can be determined as the preset curvature.

[0151] Considering that an electronic device may be used by different users, in this embodiment, by identifying the user's identity information and obtaining the curvature corresponding to the identity information from the curvature database as the preset curvature, it is possible to quickly and accurately configure different preset curvatures according to different users.

[0152] In some other implementations, users can customize preset curvature on the electronic device. For example, during the fingerprint enrollment stage, the electronic device can display a curvature input interface where users can input their own custom curvature. When the user unlocks the electronic device with their fingerprint the next time, the electronic device can use the user-customized curvature as the preset curvature.

[0153] In step S204, if the unfolded fingerprint image matches the preset fingerprint image, the electronic device is unlocked.

[0154] In some implementations, step S204 may include: acquiring the deformation between the fingerprint image and the unfolded fingerprint image. If the deformation satisfies a preset deformation condition, it is determined whether the unfolded fingerprint image matches a preset fingerprint image. If the unfolded fingerprint image matches the preset fingerprint image, the electronic device is unlocked.

[0155] Optionally, since the fingerprint image unfolded from the latitude and longitude lines of a standard planar fingerprint does not have the curvature of a spherical shape, the unfolded image remains the same as the original fingerprint image without deformation. Therefore, if the deformation exceeds a deformation threshold, it can be determined that the deformation satisfies the deformation condition, thereby improving the accuracy of fingerprint recognition. Optionally, the deformation can be the latitude or longitude change between the original fingerprint image and the unfolded fingerprint image.

[0156] Optionally, standard shape variables can be pre-stored in the electronic device. If the shape variable is consistent with or only slightly different from the standard shape variable, it can be determined that the shape variable meets the shape variable setting condition. The standard shape variable can be calculated based on multiple historical shape variables obtained from multiple fingerprint unfoldings in historical records; specifically, it can be the average of multiple historical shape variables. In some implementations, such as... Figure 9 As shown, the preset fingerprint image in step S204 can be obtained in the following way:

[0157] Step S2041: When the user registers their fingerprint on the electronic device, the fingerprint image is acquired through the optical fingerprint sensor of the electronic device.

[0158] Step S2042: Perform fingerprint unfolding processing on the fingerprint image according to the preset curvature to obtain the unfolded fingerprint image.

[0159] Step S2043: Store the unfolded fingerprint image as a preset fingerprint image in the electronic device.

[0160] The specific implementation methods of steps S2041 to S2043 can be referred to steps S101 to S103, and therefore will not be repeated here.

[0161] In this embodiment, when a user registers their fingerprint on an electronic device, the electronic device acquires a fingerprint image through its optical fingerprint sensor, and performs fingerprint unfolding processing on the fingerprint image according to a preset curvature to obtain an unfolded fingerprint image. The unfolded fingerprint image is then stored in the electronic device as a preset fingerprint image. This ensures that the registered fingerprint image has a high level of anti-counterfeiting capability. In addition, it avoids the need for the user to press the screen for a large area and for a long time to register the fingerprint image, thus improving the efficiency of fingerprint registration.

[0162] After acquiring the unfolded fingerprint image, the electronic device compares the unfolded fingerprint image with a preset fingerprint image. If the comparison results determine that the unfolded fingerprint image and the preset fingerprint image are identical or that their similarity is greater than the preset similarity, then the unfolded fingerprint image and the preset fingerprint image are matched, thereby unlocking the electronic device.

[0163] For example, such as Figure 10 As shown, Figure 10 The image on the left is a schematic diagram of a two-dimensional planar fingerprint image unfolded using the Mercator method of this embodiment. This is a fingerprint image unfolded from the latitude and longitude lines of a standard planar fingerprint. Because a two-dimensional fingerprint itself does not have spherical curvature, the unfolded image remains the same as the original fingerprint image. The divided latitudinal regions are all equal in latitude, without any difference in elevation, thus avoiding image stretching distortion. Figure 10 The fingerprint image on the right is a 3D fingerprint image captured using a 3D finger (i.e., including the finger's curvature). Since a 3D finger has a spherical curved shape, this 3D fingerprint image, after being unfolded using the Mercator algorithm, exhibits high and low latitudes. High-latitude regions are those far from the equator, and the deformation in these regions increases with distance from the equator. This is reflected in the unfolded image as an elongated fingerprint pattern in high-latitude regions. These feature points can be used for anti-counterfeiting because the fake fingerprint on the left cannot produce high-latitude shape distortions, thus serving an anti-counterfeiting function. Optionally, when comparing fingerprint images, the electronic device can determine the authenticity of the fingerprint by distinguishing whether the deformation of the captured image is the same as that of the image to be compared.

[0164] In this embodiment, when a user unlocks an electronic device with their fingerprint, the contact information between the user's finger and the screen of the electronic device is acquired. If the contact information meets preset conditions, a fingerprint image is acquired through the optical fingerprint sensor of the electronic device. This allows the optical fingerprint sensor to be activated to collect a fingerprint image only when the user's contact is confirmed to be valid, preventing accidental activation of the optical fingerprint sensor. Furthermore, unlike traditional fingerprint sensors that require extensive and prolonged pressure from the user to collect a fingerprint image, this embodiment avoids the need for traditional fingerprint sensors. Fingerprint image collection can be performed as soon as the contact information meets the preset conditions, improving collection efficiency and thus shortening the unlocking time.

[0165] Figure 11 This is a block diagram illustrating a fingerprint unlocking device according to an exemplary embodiment. (Refer to...) Figure 11 The device 300 includes a fingerprint image acquisition module 310, an unfolding module 320, and an unlocking module 330.

[0166] The fingerprint image acquisition module 310 is configured to acquire a fingerprint image through the optical fingerprint sensor of the electronic device when the user unlocks the electronic device with his / her fingerprint.

[0167] The unfolding module 320 is configured to perform fingerprint unfolding processing on the fingerprint image according to a preset curvature to obtain the unfolded fingerprint image.

[0168] The unlocking module 330 is configured to unlock the electronic device when the unfolded fingerprint image matches a preset fingerprint image.

[0169] In some embodiments, the fingerprint image acquisition module 310 includes:

[0170] The contact information acquisition submodule is configured to acquire contact information between the user's finger and the screen of the electronic device.

[0171] The fingerprint image acquisition submodule is configured to acquire a fingerprint image through the optical fingerprint sensor of the electronic device when the contact information meets preset conditions.

[0172] In some embodiments, the contact information includes the contact area, and the fingerprint image acquisition module 310 further includes:

[0173] The first judgment submodule determines that the contact information meets the preset conditions when the contact area is greater than or equal to the area threshold, wherein the area threshold is less than the contact area when the user's finger is in full contact with the screen.

[0174] In some implementations, the contact information also includes contact duration. The fingerprint image acquisition module 310 further includes:

[0175] The second judgment submodule is configured to determine that the contact information meets the preset conditions when the contact area is greater than or equal to the area threshold and the contact duration is greater than or equal to the duration threshold.

[0176] In some implementations, the unfolding module 320 is specifically configured to: perform fingerprint unfolding processing on the fingerprint image according to a preset curvature and Mercator algorithm to obtain the unfolded fingerprint image.

[0177] In some embodiments, the unfolding module 320 includes:

[0178] The coordinate information submodule is configured to acquire coordinate information in a preset rectangular coordinate system corresponding to the fingerprint image. This preset rectangular coordinate system is pre-established on the screen of the electronic device.

[0179] The calculation submodule is configured to substitute the coordinate information and the preset curvature into the Mercator projection back solution formula for calculation to obtain the longitude and latitude corresponding to the coordinate information.

[0180] The construction submodule is configured to build the unfolded fingerprint image based on the latitude and longitude.

[0181] In some implementations, the unlocking module 330 includes:

[0182] The deformation acquisition submodule is configured to acquire the deformation between the fingerprint image and the unfolded fingerprint image.

[0183] The judgment submodule is configured to determine whether the expanded fingerprint image matches the preset fingerprint image when the deformation meets the preset deformation conditions.

[0184] The unlocking submodule is configured to unlock the electronic device when the unfolded fingerprint image matches a preset fingerprint image.

[0185] In some embodiments, the fingerprint unlocking device 300 further includes a preset curvature determination module, which is configured to: acquire multiple sample fingerprint images of the user through an optical fingerprint sensor; acquire the curvature corresponding to each sample fingerprint image to obtain multiple sample curvatures; calculate the average of the multiple sample curvatures and determine the calculation result as the preset curvature.

[0186] In some implementations, the preset curvature determination module is further configured to: identify the user's identity information; and retrieve the curvature corresponding to the identity information from a curvature database as the preset curvature.

[0187] In some embodiments, the fingerprint unlocking device 300 further includes an enrollment module, which is configured to:

[0188] When a user registers their fingerprint on an electronic device, the device acquires a fingerprint image through its optical fingerprint sensor. The fingerprint image is then unfolded according to a preset curvature to obtain the unfolded fingerprint image, which is then stored in the electronic device as the preset fingerprint image.

[0189] Regarding the apparatus in the above embodiments, the specific manner in which each module performs its operation has been described in detail in the embodiments related to the method, and will not be elaborated upon here.

[0190] This disclosure also provides a computer-readable storage medium having stored thereon computer program instructions that, when executed by a processor, implement the steps of the fingerprint unlocking method provided in this disclosure.

[0191] Figure 12 This is a block diagram illustrating an electronic device 800 according to an exemplary embodiment. For example, the electronic device 800 may be a mobile phone, computer, smart lock, tablet device, smart wearable device, etc.

[0192] Reference Figure 12 The electronic device 800 may include one or more of the following components: a processing component 802, a memory 804, a power component 806, a multimedia component 808, an audio component 810, an input / output (I / O) interface 812, a sensor component 814, and a communication component 816.

[0193] Processing component 802 typically controls the overall operation of electronic device 800, such as operations associated with display, data processing, data communication, and recording. Processing component 802 may include one or more processors 820 to execute instructions to perform all or part of the steps of the methods described above. Furthermore, processing component 802 may include one or more modules to facilitate interaction between processing component 802 and other components. For example, processing component 802 may include a multimedia module to facilitate interaction between multimedia component 808 and processing component 802.

[0194] Memory 804 is configured to store various types of data to support the operation of electronic device 800. Examples of such data include instructions for any application or method operating on electronic device 800, preset fingerprint images, preset curvatures, user identification information, area thresholds, pressure thresholds, duration thresholds, etc. Memory 804 can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk.

[0195] Power component 806 provides power to various components of electronic device 800. Power component 806 may include a power management system, one or more power supplies, and other components associated with generating, managing, and distributing power to electronic device 800.

[0196] Multimedia component 808 includes a screen that provides an output interface between the electronic device 800 and the user. In some embodiments, the screen may include a liquid crystal display (LCD) and a touch panel (TP). If the screen includes a touch panel, the screen may be implemented as a touchscreen to receive input signals from the user. The touch panel includes one or more touch sensors to sense touches, swipes, and gestures on the touch panel. The touch sensors may sense not only the boundaries of the touch or swipe action but also the duration and pressure associated with the touch or swipe operation. In some embodiments, multimedia component 808 includes a front-facing camera and / or a rear-facing camera. When the electronic device 800 is in an operating mode, such as a shooting mode or a video mode, the front-facing camera and / or the rear-facing camera may receive external multimedia data. Each front-facing camera and rear-facing camera may be a fixed optical lens system or have focal length and optical zoom capabilities.

[0197] Audio component 810 is configured to output and / or input audio signals. For example, audio component 810 includes a microphone (MIC) configured to receive external audio signals when electronic device 800 is in an operating mode, such as call mode, recording mode, and voice recognition mode. The received audio signals may be further stored in memory 804 or transmitted via communication component 816. In some embodiments, audio component 810 also includes a speaker for outputting audio signals.

[0198] I / O interface 812 provides an interface between processing component 802 and peripheral interface modules, such as keyboards, click wheels, buttons, etc. These buttons may include, but are not limited to, home buttons, volume buttons, power buttons, and lock buttons.

[0199] Sensor assembly 814 includes one or more sensors for providing state assessments of various aspects of electronic device 800. For example, sensor assembly 814 can detect the on / off state of electronic device 800, the relative positioning of components such as the display and keypad of electronic device 800, changes in position of electronic device 800 or a component of electronic device 800, the presence or absence of user contact with electronic device 800, orientation or acceleration / deceleration of electronic device 800, and temperature changes of electronic device 800. Sensor assembly 814 may include a proximity sensor configured to detect the presence of nearby objects without any physical contact. Sensor assembly 814 may also include a light sensor, such as a CMOS or CCD image sensor, for use in imaging applications. In some embodiments, sensor assembly 814 may also include an accelerometer, gyroscope, magnetometer, pressure sensor, or temperature sensor. Optionally, sensor assembly 814 may also include at least one optical fingerprint sensor and at least one distance sensor array, wherein the optical fingerprint sensor is used to acquire an image of the user's fingerprint, and the distance sensor array is used to acquire the distance between the user's finger and the screen.

[0200] Communication component 816 is configured to facilitate wired or wireless communication between electronic device 800 and other devices. Electronic device 800 can access wireless networks based on communication standards, such as WiFi, 2G, or 3G, or combinations thereof. In one exemplary embodiment, communication component 816 receives broadcast signals or broadcast-related information from an external broadcast management system via a broadcast channel. In one exemplary embodiment, communication component 816 also includes a near-field communication (NFC) module to facilitate short-range communication. For example, the NFC module may be implemented based on radio frequency identification (RFID) technology, Infrared Data Association (IrDA) technology, ultra-wideband (UWB) technology, Bluetooth (BT) technology, and other technologies.

[0201] In an exemplary embodiment, the electronic device 800 may be implemented by one or more application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field-programmable gate arrays (FPGAs), controllers, microcontrollers, microprocessors, or other electronic components to perform the methods described above.

[0202] In an exemplary embodiment, a non-transitory computer-readable storage medium including instructions is also provided, such as a memory 804 including instructions, which can be executed by a processor 820 of an electronic device 800 to perform the above-described method. For example, the non-transitory computer-readable storage medium may be a ROM, random access memory (RAM), CD-ROM, magnetic tape, floppy disk, and optical data storage device, etc.

[0203] In another exemplary embodiment, a computer program product is also provided, the computer program product comprising a computer program executable by a programmable device, the computer program having a code portion for performing the fingerprint unlocking method described above when executed by the programmable device.

[0204] Other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the specification and practice of this disclosure. This application is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this disclosure are indicated by the following claims.

[0205] It should be understood that this disclosure is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this disclosure is limited only by the appended claims.

Claims

1. A fingerprint unlocking method, characterized in that, include: When a user unlocks an electronic device with their fingerprint, a fingerprint image is acquired through the optical fingerprint sensor of the electronic device. The fingerprint image is unfolded according to a preset curvature to obtain the unfolded fingerprint image. If the unfolded fingerprint image matches a preset fingerprint image, the electronic device is unlocked; Before performing fingerprint unfolding processing on the fingerprint image according to a preset curvature to obtain the unfolded fingerprint image, the method further includes: The optical fingerprint sensor acquires multiple sample fingerprint images of the user. Obtain the curvature corresponding to each sample fingerprint image to obtain multiple sample curvatures, including: comparing the similarity of each sample fingerprint image with multiple standard fingerprint images, finding the standard fingerprint image that matches each sample fingerprint image, and determining the sample curvature corresponding to the standard fingerprint image that matches it as the sample curvature corresponding to the sample fingerprint image, wherein a mapping relationship table between multiple sample curvatures and multiple standard fingerprint images is preset. The mean curvature of the multiple samples is calculated, and the calculation result is determined as the preset curvature.

2. The fingerprint unlocking method according to claim 1, characterized in that, The acquisition of a fingerprint image via the optical fingerprint sensor of the electronic device includes: Acquire contact information between the user's finger and the screen of the electronic device; If the contact information meets the preset conditions, a fingerprint image is acquired through the optical fingerprint sensor of the electronic device.

3. The fingerprint unlocking method according to claim 2, characterized in that, The contact information includes the contact area, and before acquiring a fingerprint image through the optical fingerprint sensor of the electronic device if the contact information meets a preset condition, the method further includes: If the contact area is greater than or equal to an area threshold, then the contact information is determined to meet a preset condition, wherein the area threshold is less than the contact area when the user's finger is in full contact with the screen.

4. The fingerprint unlocking method according to claim 3, characterized in that, The contact information also includes contact duration, and before acquiring a fingerprint image through the optical fingerprint sensor of the electronic device if the contact information meets preset conditions, it further includes: If the contact area is greater than or equal to the area threshold and the contact duration is greater than or equal to the duration threshold, then the contact information is determined to meet the preset conditions.

5. The fingerprint unlocking method according to claim 1, characterized in that, The step of performing fingerprint unfolding processing on the fingerprint image according to a preset curvature to obtain the unfolded fingerprint image includes: The fingerprint image is unfolded according to the preset curvature and Mercator algorithm to obtain the unfolded fingerprint image.

6. The fingerprint unlocking method according to claim 5, characterized in that, The step of performing fingerprint unfolding processing on the fingerprint image according to a preset curvature and Mercator algorithm to obtain the unfolded fingerprint image includes: Obtain the coordinate information of the fingerprint image in a preset rectangular coordinate system, which is pre-established on the screen of the electronic device; Substitute the coordinate information and the preset curvature into the Mercator projection back solution formula for calculation to obtain the longitude and latitude corresponding to the coordinate information; The unfolded fingerprint image is constructed based on the latitude and longitude.

7. The fingerprint unlocking method according to any one of claims 1 to 6, characterized in that, The step of unlocking the electronic device if the unfolded fingerprint image matches a preset fingerprint image includes: Obtain the deformation between the fingerprint image and the unfolded fingerprint image; If the deformation satisfies the preset deformation conditions, then determine whether the unfolded fingerprint image matches the preset fingerprint image; If the unfolded fingerprint image matches a preset fingerprint image, the electronic device is unlocked.

8. The fingerprint unlocking method according to any one of claims 1 to 6, characterized in that, Before performing fingerprint unfolding processing on the fingerprint image according to a preset curvature to obtain the unfolded fingerprint image, the method further includes: Identify the user's identity information; The curvature corresponding to the identity information is obtained from the curvature database as the preset curvature.

9. The fingerprint unlocking method according to any one of claims 1 to 6, characterized in that, The preset fingerprint image is obtained in the following way: When a user registers their fingerprint on an electronic device, the fingerprint image is acquired through the optical fingerprint sensor of the electronic device. The fingerprint image is unfolded according to a preset curvature to obtain the unfolded fingerprint image. The unfolded fingerprint image is stored as the preset fingerprint image in the electronic device.

10. A fingerprint unlocking device, characterized in that, include: The fingerprint image acquisition module is configured to acquire a fingerprint image through the optical fingerprint sensor of the electronic device when the user unlocks the electronic device with his / her fingerprint. The unfolding module is configured to perform fingerprint unfolding processing on the fingerprint image according to a preset curvature to obtain an unfolded fingerprint image; The unlocking module is configured to unlock the electronic device when the unfolded fingerprint image matches a preset fingerprint image; The preset curvature determination module includes: The sample fingerprint image acquisition submodule is configured to acquire multiple sample fingerprint images of the user through the optical fingerprint sensor; The sample curvature acquisition submodule is configured to acquire the curvature corresponding to each sample fingerprint image to obtain multiple sample curvatures, including: performing similarity comparison between each sample fingerprint image and multiple standard fingerprint images, finding the standard fingerprint image that matches each sample fingerprint image, and determining the sample curvature corresponding to the matching standard fingerprint image as the sample curvature corresponding to the sample fingerprint image, wherein a mapping relationship table between multiple sample curvatures and multiple standard fingerprint images is preset; The first preset curvature determination submodule is configured to calculate the mean of the curvatures of the plurality of samples and determine the calculation result as the preset curvature.

11. The fingerprint unlocking device according to claim 10, characterized in that, The fingerprint image acquisition module includes: The contact information acquisition submodule is configured to acquire contact information between the user's finger and the screen of the electronic device; The fingerprint image acquisition submodule is configured to acquire a fingerprint image through the optical fingerprint sensor of the electronic device when the contact information meets preset conditions.

12. The fingerprint unlocking device according to claim 11, characterized in that, The contact information includes the contact area, and the fingerprint image acquisition module further includes: The first judgment submodule determines that the contact information meets a preset condition when the contact area is greater than or equal to an area threshold, wherein the area threshold is less than the contact area when the user's finger is in full contact with the screen.

13. The fingerprint unlocking device according to claim 12, characterized in that, The contact information also includes the contact duration, and the fingerprint image acquisition module further includes: The second judgment submodule is configured to determine that the contact information meets preset conditions when the contact area is greater than or equal to an area threshold and the contact duration is greater than or equal to a duration threshold.

14. The fingerprint unlocking device according to claim 10, characterized in that, The unfolding module is also configured to: The fingerprint image is unfolded according to the preset curvature and Mercator algorithm to obtain the unfolded fingerprint image.

15. The fingerprint unlocking device according to claim 14, characterized in that, The unfolding module includes: The coordinate information submodule is configured to acquire coordinate information in a preset rectangular coordinate system corresponding to the fingerprint image, and the preset rectangular coordinate system is pre-established on the screen of the electronic device; The calculation submodule is configured to substitute the coordinate information and the preset curvature into the Mercator projection back solution formula for calculation to obtain the longitude and latitude corresponding to the coordinate information; A construction submodule is configured to construct the unfolded fingerprint image based on the latitude and longitude.

16. The fingerprint unlocking device according to any one of claims 10 to 15, characterized in that, The unlocking module includes: The deformation acquisition submodule is configured to acquire the deformation between the fingerprint image and the unfolded fingerprint image; The judgment submodule is configured to determine whether the unfolded fingerprint image matches the preset fingerprint image when the deformation meets the preset deformation conditions; The unlocking submodule is configured to unlock the electronic device when the unfolded fingerprint image matches a preset fingerprint image.

17. The fingerprint unlocking device according to any one of claims 10 to 15, characterized in that, The preset curvature determination module further includes: The identification submodule is configured to identify the user's identity information; The second preset curvature determination submodule is configured to obtain the curvature corresponding to the identity information from the curvature database as the preset curvature.

18. The fingerprint unlocking device according to any one of claims 10 to 15, characterized in that, The fingerprint unlocking device further includes an enrollment module, which includes: The detection module is configured to acquire a fingerprint image through the optical fingerprint sensor of the electronic device when a user registers their fingerprint on the electronic device. The fingerprint unfolding module is configured to perform fingerprint unfolding processing on the fingerprint image according to a preset curvature to obtain the unfolded fingerprint image; The input module is configured to store the unfolded fingerprint image as the preset fingerprint image in the electronic device.

19. An electronic device, characterized in that, include: processor; Memory used to store processor-executable instructions; An optical fingerprint sensor used to acquire fingerprint images; The processor is configured as follows: When a user unlocks an electronic device with their fingerprint, the optical fingerprint sensor of the electronic device is controlled to acquire a fingerprint image. The fingerprint image is unfolded according to a preset curvature to obtain the unfolded fingerprint image. If the unfolded fingerprint image matches a preset fingerprint image, the electronic device is unlocked; Before performing fingerprint unfolding processing on the fingerprint image according to a preset curvature to obtain the unfolded fingerprint image, the method further includes: The optical fingerprint sensor acquires multiple sample fingerprint images of the user. Obtain the curvature corresponding to each sample fingerprint image to obtain multiple sample curvatures, including: comparing the similarity of each sample fingerprint image with multiple standard fingerprint images, finding the standard fingerprint image that matches each sample fingerprint image, and determining the sample curvature corresponding to the standard fingerprint image that matches it as the sample curvature corresponding to the sample fingerprint image, wherein a mapping relationship table between multiple sample curvatures and multiple standard fingerprint images is preset. The mean curvature of the multiple samples is calculated, and the calculation result is determined as the preset curvature.

20. A computer-readable storage medium having computer program instructions stored thereon, characterized in that, When executed by a processor, the program instructions implement the steps of the method described in any one of claims 1 to 9.

Images