Dynamic acquisition method and device of ultrasonic fingerprint data and electronic equipment

Abstract

The invention provides a dynamic acquisition method and device for ultrasonic fingerprint data and electronic equipment, and can be applied to the technical field of fingerprint identification. Based on the method, during specific implementation, contact pressure information of a current finger relative to a fingerprint acquisition area and / or surface characteristic information of the finger can be firstly acquired; adjusting emission parameters of ultrasonic waves according to the contact pressure information and / or the surface characteristic information of the finger; and collecting target fingerprint data based on the adjusted ultrasonic waves. Therefore, the contact state of the finger can be determined, different conditions can be intelligently distinguished according to the contact state of the finger, the emission parameters of the ultrasonic waves are adaptively and dynamically adjusted, and then fingerprint data with fine surface features and small errors can be acquired based on the adjusted ultrasonic waves. And related fingerprint data processing such as fingerprint identification and the like can be accurately realized subsequently based on the fingerprint data.

Description

Technical Field

[0001] This specification belongs to the technical field of fingerprint recognition, and particularly relates to a method, device, and electronic device for dynamically collecting ultrasonic fingerprint data. Background Art

[0002] When a user's finger touches the fingerprint collection area to collect fingerprints, due to differences in finger pressing habits, finger surface conditions, etc. among different users, there will be significant differences in the actual contact situation between the fingerprint collection area and the finger, affecting the effective collection of fingerprint data and further affecting the accuracy of subsequent fingerprint recognition.

[0003] In response to the above problems, no effective solution has been proposed yet. Summary of the Invention

[0004] This specification provides a method, device, and electronic device for dynamically collecting ultrasonic fingerprint data, which can determine and adaptively adjust the emission parameters of ultrasonic waves according to the contact state of the finger, and then can collect fingerprint data with fine surface features and small errors based on the adjusted ultrasonic waves, so as to accurately perform subsequent fingerprint data processing such as fingerprint recognition based on the fingerprint data.

[0005] This specification provides a method for dynamically collecting ultrasonic fingerprint data, including:

[0006] Obtaining contact pressure information of the current finger relative to the fingerprint collection area and / or surface characteristic information of the finger;

[0007] Adjusting the emission parameters of ultrasonic waves according to the contact pressure information and / or surface characteristic information of the finger;

[0008] Collecting target fingerprint data based on the adjusted ultrasonic waves.

[0009] In one embodiment, the ultrasonic waves include focused waves and / or plane waves;

[0010] Correspondingly, the emission parameters of the ultrasonic waves include: frequency and / or phase.

[0011] In one embodiment, the surface characteristic information includes at least one of the following: roughness, smoothness, humidity.

[0012] In one embodiment, adjusting the emission parameters of ultrasonic waves according to the contact pressure information and / or surface characteristic information of the finger includes:

[0013] When the contact pressure indicated by the contact pressure information is greater than a preset first pressure threshold, reducing the frequency of the ultrasonic waves according to a first adjustment rule;

[0014] When the contact pressure indicated by the contact pressure information is less than a preset second pressure threshold, increase the frequency of the ultrasonic wave according to a first adjustment rule; wherein, the preset first pressure threshold is greater than the preset second pressure threshold.

[0015] In one embodiment, adjusting the transmission parameters of the ultrasonic wave according to the contact pressure information and / or the surface characteristic information of the finger includes:

[0016] When the roughness of the finger indicated by the surface characteristic information is greater than a preset first roughness threshold, increase the phase of the ultrasonic wave according to a second adjustment rule;

[0017] When the roughness of the finger indicated by the surface characteristic information is less than a preset second roughness threshold, decrease the phase of the ultrasonic wave according to a second adjustment rule; wherein, the preset first roughness threshold is greater than the preset second roughness threshold.

[0018] In one embodiment, adjusting the transmission parameters of the ultrasonic wave according to the contact pressure information and / or the surface characteristic information of the finger includes:

[0019] When the humidity of the finger indicated by the surface characteristic information is greater than a preset first humidity threshold, decrease the frequency of the ultrasonic wave according to a third adjustment rule;

[0020] When the humidity of the finger indicated by the surface characteristic information is less than a preset second humidity threshold, increase the frequency of the ultrasonic wave according to a third adjustment rule; wherein, the preset first humidity threshold is greater than the preset second humidity threshold.

[0021] In one embodiment, the method further includes:

[0022] Determine a matching target angle scanning range;

[0023] According to the target angle scanning range, control the ultrasonic transducer to perform multi-angle scanning to obtain a plurality of first type echo signals at different angles;

[0024] Obtain target fingerprint data according to the plurality of first type echo signals.

[0025] In one embodiment, obtaining target fingerprint data according to the plurality of first type echo signals includes:

[0026] According to the plurality of first type echo signals, determine the depth information at multiple angles on the finger surface by calculating the signal propagation time;

[0027] Extract corresponding signal parameters according to the plurality of first type echo signals; wherein, the signal parameters include at least one of the following: intensity, phase, and time delay;

[0028] Using depth information at multiple angles and corresponding signal parameters, target fingerprint data is obtained through data fusion.

[0029] In one embodiment, using depth information at multiple angles and corresponding signal parameters, target fingerprint data is obtained through data fusion, including:

[0030] Performing alignment processing and calibration processing on the depth information at multiple angles respectively to obtain multiple processed depth information;

[0031] According to the signal parameters, combining and using the multiple processed depth information to construct a three-dimensional fingerprint image as the target fingerprint data.

[0032] In one embodiment, the method further includes:

[0033] Determining a matching target frequency range and target phase range;

[0034] According to the target frequency range and target phase range, controlling the ultrasonic transducer to perform multi-frequency and multi-phase scanning to obtain multiple second-type echo signals;

[0035] According to the multiple second-type echo signals, obtaining the target fingerprint data.

[0036] This specification also provides a dynamic acquisition device for ultrasonic fingerprint data, including:

[0037] An acquisition module for acquiring the contact pressure information of the current finger relative to the fingerprint acquisition area and / or the surface characteristic information of the finger;

[0038] An adjustment module for adjusting the emission parameters of the ultrasonic wave according to the contact pressure information and / or the surface characteristic information of the finger;

[0039] An acquisition module for acquiring the target fingerprint data based on the adjusted ultrasonic wave.

[0040] This specification also provides an electronic device, including a processor and a memory for storing processor-executable instructions, and when the processor executes the instructions, the steps of the dynamic acquisition method for ultrasonic fingerprint data are implemented.

[0041] This specification also provides a computer-readable storage medium, on which computer instructions are stored, and when the instructions are executed by a processor, the steps of the dynamic acquisition method for ultrasonic fingerprint data are implemented.

[0042] Based on the dynamic acquisition method, device, and electronic device for ultrasonic fingerprint data provided in this specification, it is possible to first obtain the contact pressure information of the current finger relative to the fingerprint acquisition area and / or the surface characteristic information of the finger; then, according to the contact pressure information and / or the surface characteristic information of the finger, the emission parameters of the ultrasonic wave are adjusted specifically; and based on the adjusted ultrasonic wave, the target fingerprint data is acquired. Thus, it is possible to determine and, according to the contact state of the finger, intelligently distinguish different situations, adaptively and dynamically adjust the emission parameters of the ultrasonic wave, and further acquire fingerprint data with fine surface features and small errors based on the adjusted ultrasonic wave, so that subsequent fingerprint data processing such as fingerprint recognition can be accurately realized based on this fingerprint data. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] To more clearly illustrate the embodiments of this specification, the drawings required for use in the embodiments will be briefly introduced below. The drawings in the following description are only some embodiments recorded in this specification. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0044] Figure 1 It is a flowchart of the dynamic acquisition method for ultrasonic fingerprint data provided by an embodiment of this specification;

[0045] Figure 2 It is a schematic diagram of an embodiment applying the dynamic acquisition method for ultrasonic fingerprint data provided by an embodiment of this specification in a scenario example;

[0046] Figure 3 It is a schematic diagram of an embodiment applying the dynamic acquisition method for ultrasonic fingerprint data provided by an embodiment of this specification in a scenario example;

[0047] Figure 4 It is a schematic diagram of an embodiment applying the dynamic acquisition method for ultrasonic fingerprint data provided by an embodiment of this specification in a scenario example;

[0048] Figure 5 It is a schematic diagram of an embodiment applying the dynamic acquisition method for ultrasonic fingerprint data provided by an embodiment of this specification in a scenario example;

[0049] Figure 6 It is a schematic diagram of the structural composition of an electronic device provided by an embodiment of this specification;

[0050] Figure 7 It is a schematic diagram of the structural composition of the dynamic acquisition device for ultrasonic fingerprint data provided by an embodiment of this specification. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0051] To enable those skilled in the art to better understand the technical solutions in this specification, the following will clearly and completely describe the technical solutions in the embodiments of this specification in conjunction with the accompanying drawings in the embodiments of this specification. Obviously, the described embodiments are only a part of the embodiments of this specification, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in this specification without creative efforts shall fall within the scope of protection of this specification.

[0052] It should be noted that the information and data related to users involved in the embodiments of this specification are all information and data authorized by users or fully authorized by relevant parties. Moreover, the processing of relevant data, such as collection, storage, use, processing, transmission, provision, disclosure, and application, all comply with relevant laws, regulations, and standards, adopt necessary confidentiality measures, do not violate public order and good customs, and provide corresponding operation entrances for users or relevant parties to choose to authorize or refuse.

[0053] It should also be noted that in the embodiments of this specification, some industry-existing solutions such as certain software, components, models, etc. may be mentioned. They should be regarded as exemplary, and their purpose is only to illustrate the feasibility in the implementation of the technical solutions of this application, but it does not mean that the applicant has already or necessarily used this solution.

[0054] Refer to Figure 1 As shown, the embodiments of this specification provide a method for dynamically collecting ultrasonic fingerprint data. Specifically, when this method is implemented, it may include the following content:

[0055] S101: Obtain the contact pressure information of the current finger relative to the fingerprint acquisition area and / or the surface characteristic information of the finger;

[0056] S102: Adjust the emission parameters of the ultrasonic wave according to the contact pressure information and / or the surface characteristic information of the finger;

[0057] S103: Collect target fingerprint data based on the adjusted ultrasonic wave.

[0058] The above method for dynamically collecting ultrasonic fingerprint data can be applied to one side of a fingerprint recognition device (or other fingerprint processing devices such as a fingerprint acquisition device). Among them, the above fingerprint recognition device can be specifically applied to an access control system, can also be applied to a smart device (for example, a smart phone), and can also be applied to device systems such as an identity information acquisition system.

[0059] The following takes the fingerprint recognition device as an example for specific illustration. For other fingerprint processing devices, reference can be made to the relevant embodiments of the fingerprint recognition device, and this specification will not elaborate.

[0060] The above fingerprint recognition device includes at least a fingerprint acquisition area. For example, the above fingerprint acquisition area can be a pressing screen. When a user performs fingerprint recognition, the user can place a finger on the fingerprint acquisition area to collect the required fingerprint data. In some cases, the user can also place a palm on the fingerprint acquisition area to collect corresponding palmprint data.

[0061] Further, a plurality of ultrasonic transducers can be arranged below the fingerprint acquisition area. Among them, the above ultrasonic transducer (or ultrasonic wave transducer) can be specifically understood as a device that can convert electromagnetic energy and mechanical energy (acoustic energy) into each other.

[0062] Specifically, the above ultrasonic transducer at least includes structures such as a piezoelectric element, an electrode, a matching layer, and a backing layer.

[0063] Among them, the above piezoelectric element is usually made of a material with piezoelectric effect. For example, piezoelectric ceramics, lithium niobate, barium titanate, lead zirconate titanate, aluminum nitride, polyvinylidene fluoride (PVDF), or polyvinylidene fluoride-trifluoroethylene copolymer (PVDF-TrFE), etc. When a voltage is applied, the piezoelectric material will deform and generate ultrasonic signals. Similarly, when receiving ultrasonic signals, the piezoelectric material will generate corresponding electrical signals. Therefore, the ultrasonic transducer can use the piezoelectric element to transmit and receive ultrasonic signals.

[0064] The above electrodes are attached to both sides of the piezoelectric element and are used to apply voltage or receive the electrical signals generated by the piezoelectric element. The electrodes are usually made of metal (such as silver or platinum), which can provide stable conductivity and can be well combined with the piezoelectric material.

[0065] The above matching layer is used to adjust the acoustic impedance difference between the piezoelectric element and the object to be measured (such as the skin of a finger or air). The matching layer can be a single-layer or multi-layer material, which can reduce the reflection loss of ultrasonic signals while improving the signal transmission efficiency of the ultrasonic transducer.

[0066] The above backing layer is arranged on the back of the piezoelectric element and is usually made of a damping material. It can absorb the backward propagation of ultrasonic signals, mainly used to reduce unnecessary echoes, prevent reflection interference, and enhance the forward-propagating ultrasonic signals.

[0067] Specifically, the above ultrasonic transducer is also connected with corresponding transmitting circuits and receiving circuits. Correspondingly, in specific implementation, different ultrasonic signals can be controlled to be emitted by the above transmitting circuit. And, the echo signals based on the emitted ultrasonic signals are received through the above receiving circuit; and according to the above echo signals, through corresponding signal processing, the required fingerprint data containing the fingerprint feature information of the user is obtained.

[0068] Specifically, the above ultrasonic transducer can support multiple different ultrasonic modes. Correspondingly, the above fingerprint recognition device can obtain fingerprint data by transmitting corresponding ultrasonic signals based on different ultrasonic modes.

[0069] Among them, the above ultrasonic modes include: focused wave mode and / or plane wave mode.

[0070] Specifically, based on the plane wave mode, multiple ultrasonic transducers on the entire surface can be simultaneously driven to transmit ultrasonic signals with the same phase and the same frequency, so as to form a plane wave and transmit it to the surface of the finger (or other detected objects such as the palm), and then rapid detection and acquisition of fingerprint feature information over a large area can be realized.

[0071] Based on the focused wave mode, the phases and frequencies of the ultrasonic signals emitted by the specified multiple ultrasonic transducers can be started and adjusted, so that the ultrasonic waves can form a focused wave in a specific area, and then detection and acquisition of fingerprint feature information in a small area with high precision can be realized.

[0072] Among them, the above plane wave mode has the characteristics of low power consumption, high frame rate, fast system response speed, large coverage area, but limited penetration and low precision compared with the focused wave mode.

[0073] The above focused wave mode has the characteristics of high precision, long penetration distance, but high power consumption, low frame rate, and long system response time compared with the plane wave mode.

[0074] Below the above fingerprint acquisition area, sensor devices such as pressure sensors and / or surface property sensors can also be arranged.

[0075] Among them, the above pressure sensor can be used to detect the magnitude of the pressure when the user presses on the fingerprint acquisition area. The above surface property sensor can be used to detect the skin surface properties (such as humidity, roughness, smoothness, etc.) of the detected object (such as a finger) when the user presses on the fingerprint acquisition area.

[0076] In addition, an adaptive control unit (such as a micro control chip, etc.) is arranged below the above fingerprint acquisition area, and the above adaptive control unit can be specifically electrically connected to the above sensor devices, transmitting circuits, etc.

[0077] The above target fingerprint data can be specifically understood as data containing the fingerprint characteristic information of the user and capable of being used for subsequent data processing such as fingerprint recognition, for example, an echo signal containing the fingerprint feature information of the user, or feature data obtained by further processing based on the above echo signal.

[0078] Based on the above fingerprint recognition device, when a user presses the fingerprint collection area, sensor devices such as pressure sensors and surface property sensors can first collect data signals that can reflect information such as contact pressure and / or finger surface properties during the user's pressing contact; and send the above data signals to the adaptive control unit; the adaptive control unit can determine the current contact pressure information and / or finger surface property information based on the above data signals, distinguish different contact situations; and adaptively and dynamically adjust the transmission parameters when the ultrasonic transducer emits ultrasonic waves through the transmission circuit; furthermore, based on the adjusted ultrasonic waves, it can better adapt to the current contact situation and collect target fingerprint data with higher accuracy and better effect.

[0079] In some embodiments, the above ultrasonic waves may specifically include focused waves; correspondingly, the adjustable transmission parameters of the ultrasonic waves may specifically include: frequency and / or phase, etc. For focused waves, the phases between different ultrasonic transducers may be different.

[0080] The above ultrasonic waves may specifically further include plane waves; correspondingly, the adjustable transmission parameters of the ultrasonic waves may specifically include: frequency and / or phase, etc. For plane waves, the phases between different ultrasonic transducers are the same.

[0081] Specifically in implementation, adjusting the transmission parameters of the ultrasonic waves according to the contact pressure information and / or finger surface property information may include: determining the type of ultrasonic wave currently used; determining the adjustable transmission parameters of the ultrasonic wave according to the currently used ultrasonic wave type; and then determining the transmission parameters of the ultrasonic wave according to the contact pressure information and / or finger surface property information.

[0082] For example, when it is determined that the type of ultrasonic wave currently used is a focused wave, the frequency and / or phase of the ultrasonic wave is adjusted according to the contact pressure information and / or finger surface property information. Another example, when it is determined that the type of ultrasonic wave currently used is a plane wave, the frequency of the ultrasonic wave is adjusted according to the contact pressure information and / or finger surface property information. Regarding how to specifically adjust the frequency and phase of the ultrasonic wave, specific descriptions will be made separately later.

[0083] It should be noted that the above-listed types of ultrasonic waves and the transmission parameters of ultrasonic waves are only illustrative explanations. Specifically in implementation, according to specific situations and processing requirements, other types of ultrasonic waves and transmission parameters (such as transmission intensity, transmission angle, etc.) matching other types of ultrasonic waves may also be included.

[0084] For example, the penetrability of ultrasonic waves can be adjusted by adjusting the frequency of ultrasonic waves. For example, when the frequency of ultrasonic waves is relatively large, the penetrability of ultrasonic waves is relatively strong; on the contrary, when the frequency of ultrasonic waves is relatively small, the penetrability of ultrasonic waves is relatively weak.

[0085] By adjusting the phase of the ultrasonic wave, the phase compensation angle of the ultrasonic reflection signal can be adjusted, and then the offset situation of the reflection signal can be adjusted to avoid image blurring in the collected image caused by signal offset.

[0086] Specifically, for example, for a focused wave, the adjustment range of the frequency can be greater than or equal to 5 MHz and less than or equal to 20 MHz; the adjustment range of the phase can be greater than or equal to 0 degrees and less than 360 degrees.

[0087] In some embodiments, in specific implementation, first, based on the plane wave mode, it can be detected whether the user is currently pressing the fingerprint collection area based on the plane wave; when it is determined that the user is currently pressing the fingerprint collection area, the contact pressure information of the current finger relative to the fingerprint collection area and / or the surface characteristic information of the finger can be collected through a corresponding sensor device; and switch from the plane wave mode to the focused wave mode; then, according to the contact pressure information and / or the surface characteristic information of the finger, the emission parameters of the focused wave are adjusted; and based on the adjusted focused wave, the target fingerprint data is collected.

[0088] In specific implementation, the pressing position of the user can also be determined according to the detection result of the plane wave; then, according to the pressing position of the user, the emission angle is adjusted to align with the pressing position of the user; and then, based on the adjusted focused wave, the target fingerprint data is collected.

[0089] In this way, it can be first detected by using the plane wave with less power consumption and faster speed to determine whether there is a user pressing the fingerprint collection area; after it is determined that there is a user pressing the fingerprint collection area; then, the adjusted focused wave with larger power consumption but higher precision and matching the current contact pressure information and / or the surface characteristic information of the finger is used to collect the required fingerprint data, so that both power consumption and precision can be taken into account, and the target fingerprint data with higher quality can be collected.

[0090] In some embodiments, the above surface characteristic information may specifically include at least one of the following: roughness, smoothness, humidity, etc.

[0091] Among them, roughness, smoothness, and humidity will affect the ultrasonic reflection signal. Generally, when the skin roughness of the detection object pressing the fingerprint collection area is large, the smoothness is small, and the humidity is large (for example, there are sweat beads on the finger), the ultrasonic reflection signal is relatively more likely to generate a phase deviation, thereby affecting the data quality of the collected fingerprint data.

[0092] In some embodiments, before specific implementation, an ultrasonic-based sample fingerprint recognition device can be used. By adjusting relevant variable factors such as contact pressure, roughness, smoothness, and humidity, a large number of experimental tests can be carried out to obtain a large number of experimental test records. Then, based on the above experimental test records, through clustering learning, analyze the influence mechanism and effect of the above variable factors on the fingerprint data collection of the sample fingerprint recognition device. Then, according to the above influence mechanism and effect, determine the ultrasonic emission parameters corresponding to each variable factor respectively. Then, select multiple sub-sample data groups corresponding to each variable factor respectively from the experimental test records; where each sub-sample data group corresponds to one variable factor. Then, according to each sub-sample data group, combined with the influence mechanism and effect of the variable factor corresponding to the sub-sample data group, fit the functional relationship between the variable factor and the corresponding ultrasonic emission parameter. According to this functional relationship, construct multiple preset adjustment rules corresponding to each variable factor respectively; where each preset adjustment rule corresponds to at least one variable factor and includes one or more reference numerical ranges regarding this variable factor, as well as the emission parameter adjustment suggestions corresponding to each reference numerical range respectively (including: the parameter type of the emission parameter to be adjusted, the adjustment method of the emission parameter, the adjustment amplitude of the emission parameter, etc.). Finally, combine multiple preset adjustment rules to establish the corresponding preset adjustment rule set.

[0093] During specific implementation, the adjustment of the ultrasonic emission parameter according to the contact pressure information and / or the surface characteristic information of the finger may include: According to the contact pressure information, query the preset adjustment rule set to determine the preset adjustment rule corresponding to the contact pressure as the first adjustment rule; then, according to the contact pressure information, query the first adjustment rule to determine the emission parameter adjustment suggestion corresponding to the reference numerical range to which the contact pressure information belongs as the first adjustment suggestion; and / or, according to the surface characteristic information of the finger (for example, roughness), query the preset adjustment rule set to determine the preset adjustment rule corresponding to the surface characteristic of the finger as the second adjustment rule (and / or the third adjustment rule corresponding to humidity); and according to the surface characteristic information of the finger, query the second adjustment rule to determine the emission parameter adjustment suggestion corresponding to the reference numerical range to which the surface characteristic information of the finger belongs as the second adjustment suggestion. Then, determine the target adjustment suggestion according to the first adjustment suggestion and / or the second adjustment suggestion; adjust the ultrasonic emission parameter according to the target adjustment suggestion.

[0094] In some embodiments, refer to Figure 2 As shown, during specific implementation, the adjustment of the ultrasonic emission parameter according to the contact pressure information and / or the surface characteristic information of the finger may include the following content:

[0095] S1: When the contact pressure indicated by the contact pressure information is greater than a preset first pressure threshold, according to the first adjustment rule, reduce the frequency of the ultrasonic wave;

[0096] S2: When the contact pressure indicated by the contact pressure information is less than a preset second pressure threshold, according to the first adjustment rule, increase the frequency of the ultrasonic wave; wherein, the preset first pressure threshold is greater than the preset second pressure threshold.

[0097] Specifically, when the contact pressure between the detection object (e.g., finger) and the fingerprint collection area is too small when the user presses the fingerprint collection area, it is easy to have insufficient contact, resulting in insufficient signals. At this time, the emission frequency of the ultrasonic wave can be reduced to weaken the projection and reflection of the ultrasonic wave, so as to be able to collect sufficient signals to generate fingerprint data with higher quality.

[0098] On the contrary, when the contact pressure between the detection object and the fingerprint collection area is too large when the user presses the fingerprint collection, it is easy to cause signal distortion due to excessive pressing. At this time, the emission frequency of the ultrasonic wave can be increased to ensure that the ultrasonic wave has sufficient penetration to collect fingerprint data with higher quality.

[0099] Among them, the above-mentioned preset first pressure threshold and preset second pressure threshold can be specifically determined according to a large number of experimental test records. Specifically, for example, the preset first pressure threshold can be 0.8 N, and the preset second pressure threshold can be 0.2 N.

[0100] During specific implementation, when the contact pressure indicated by the contact pressure information is greater than the preset first pressure threshold, it can be determined that the current is in a high-pressure state. At this time, according to the first adjustment rule, the frequency of the ultrasonic wave can be specifically reduced. For example, the emission frequency of the ultrasonic wave is reduced from the original 8 MHz to 5 MHz, so as to be able to collect fingerprint data with higher quality.

[0101] When the contact pressure indicated by the contact pressure information is less than the preset second pressure threshold, it can be determined that the current is in a low-pressure state. At this time, according to the first adjustment rule, the frequency of the ultrasonic wave can be specifically increased. For example, the emission frequency of the ultrasonic wave is increased from the original 5 MHz to 8 MHz or even higher, so as to be able to collect fingerprint data with higher quality.

[0102] When the contact pressure indicated by the contact pressure information is less than or equal to the preset first pressure threshold and greater than or equal to the preset second pressure threshold, it can be determined that the current is in a proper pressure state. At this time, the frequency of the ultrasonic wave can be not adjusted, and then the current frequency of the ultrasonic wave can be continued to be used.

[0103] Based on the above embodiments, according to the contact pressure information, by differentiating different pressure states, the emission parameters of the ultrasonic wave can be finely and accurately adjusted adaptively.

[0104] In some embodiments, referring to Figure 3 as shown, the above-mentioned adjustment of the emission parameters of the ultrasonic wave according to the contact pressure information and / or the surface characteristic information of the finger may specifically include the following content when implemented:

[0105] S1: When the roughness of the finger indicated by the surface characteristic information is greater than a preset first roughness threshold, according to the second adjustment rule, increase the phase of the ultrasonic wave;

[0106] S2: When the roughness of the finger indicated by the surface characteristic information is less than a preset second roughness threshold, according to the second adjustment rule, decrease the phase of the ultrasonic wave; wherein, the preset first roughness threshold is greater than the preset second roughness threshold.

[0107] Specifically, when the surface of the detection object is rough and not smooth when the user presses the fingerprint collection area, the reflected signal is likely to have a phase deviation or signal shift, which will further cause interference and affect the quality of the collected fingerprint data. Further, through a large number of experimental tests, it is also found that the effects generated by different rough states will also vary, resulting in both overly rough and overly smooth states affecting the quality of the collected fingerprint data.

[0108] Among them, the above-mentioned preset first roughness threshold and preset second roughness threshold can be specifically determined according to a large number of experimental test records. Specifically, for example, the preset first roughness threshold can be 1.5, and the preset second roughness threshold can be 0.5.

[0109] When implemented specifically, when the roughness of the finger indicated by the surface characteristic information is greater than the preset first roughness threshold, it can be determined that the current is in a high roughness state (too rough). At this time, according to the second adjustment rule, the phase of the ultrasonic wave can be increased specifically. For example, the emission phase of the ultrasonic wave is increased from the original 0 degrees to 45 degrees to increase the phase compensation, so as to avoid image blurring caused by signal shift, and thus higher-quality fingerprint data can be collected.

[0110] When the roughness of the finger indicated by the surface characteristic information is less than the preset second roughness threshold, it can be determined that the current is in a low roughness state (too smooth). At this time, according to the second adjustment rule, the phase of the ultrasonic wave can be decreased specifically. For example, the emission phase of the ultrasonic wave is decreased from the original 30 degrees to 10 degrees to reduce the phase compensation, so as to maintain the accuracy and consistency of the signal, and thus higher-quality fingerprint data can be collected.

[0111] When the roughness of the finger indicated by the surface characteristic information is greater than or equal to a preset second roughness threshold and less than or equal to a preset first roughness threshold, it can be determined that the current is in a normal roughness state. At this time, the phase can be not adjusted.

[0112] Based on the above embodiments, according to the surface characteristic information, by distinguishing different roughness states, the emission parameters of the ultrasonic wave can be finely and accurately adjusted adaptively.

[0113] For the embodiments regarding smoothness, reference can be made to the above embodiments regarding roughness, and this specification will not elaborate.

[0114] In some embodiments, the above-mentioned adjusting the emission parameters of the ultrasonic wave according to the contact pressure information and / or the surface characteristic information of the finger may specifically include the following when implemented:

[0115] S1: When the humidity of the finger indicated by the surface characteristic information is greater than a preset first humidity threshold, according to the third adjustment rule, reduce the frequency of the ultrasonic wave;

[0116] S2: When the humidity of the finger indicated by the surface characteristic information is less than a preset second humidity threshold, according to the third adjustment rule, increase the frequency of the ultrasonic wave; wherein, the preset first humidity threshold is greater than the preset second humidity threshold.

[0117] Specifically, when the user presses the fingerprint collection area, the humidity of the detection object will affect the moisture on the skin surface of the detection object, and the moisture will in turn affect the transmission and reflection of the ultrasonic wave signal.

[0118] Among them, the above-mentioned preset first humidity threshold and preset second humidity threshold can specifically be determined according to a large number of experimental test records.

[0119] When implemented, when the humidity indicated by the surface characteristic information is greater than the preset first humidity threshold, it can be determined that the current is in a wet state (too much moisture on the skin surface). At this time, according to the third adjustment rule corresponding to the humidity, the frequency of the ultrasonic wave can be specifically reduced to weaken the signal transmissibility, so that higher-quality fingerprint data can be collected.

[0120] When the humidity of the finger indicated by the surface characteristic information is less than the preset second roughness threshold, it can be determined that the current is in a dry state (too little moisture on the skin surface). At this time, according to the third adjustment rule, the frequency of the ultrasonic wave can be specifically increased to enhance the signal transmissibility, so that higher-quality fingerprint data can be collected.

[0121] When the humidity of the finger indicated by the surface characteristic information is greater than or equal to a preset second humidity threshold and less than or equal to a preset first humidity threshold, it can be determined that the current is in a normal humidity state. At this time, the frequency can be not adjusted.

[0122] Based on the above embodiments, according to the surface characteristic information, by distinguishing different humidity states, the emission parameters of the ultrasonic wave can be finely and accurately adjusted adaptively.

[0123] In some embodiments, during the process of collecting target fingerprint data based on the adjusted ultrasonic wave, the emission intensity of the ultrasonic transducer can also be dynamically adjusted by receiving and according to the corresponding echo signal, so that the adjusted ultrasonic wave can be focused on the area of interest as much as possible, and thus target fingerprint data with relatively better effects can be obtained.

[0124] In some embodiments, the above-mentioned collecting of target fingerprint data based on the adjusted ultrasonic wave, in specific implementation, may include: emitting the adjusted ultrasonic wave according to the emission parameters of the adjusted ultrasonic wave; and receiving the corresponding echo signal; according to the echo signal, through corresponding signal processing, obtaining the target fingerprint data containing the fingerprint feature information of the user required.

[0125] Specifically, after receiving the echo signal, the echo signal can be preprocessed first. Among them, the preprocessing may include: signal filtering processing and / or noise suppression processing. Thus, an identifiable preprocessed echo signal can be obtained, and further, based on the above preprocessed echo signal, target fingerprint data with relatively higher accuracy and relatively smaller error can be obtained.

[0126] In some embodiments, when specifically collecting target fingerprint data, for different situations or scenarios, target fingerprint data can be collected only based on one ultrasonic wave; or target fingerprint data can be collected based on multiple different ultrasonic waves at the same time. Among them, the multiple different ultrasonic waves may include one or more combinations of the following: ultrasonic waves with multiple different emission angles, ultrasonic waves with multiple different frequencies, ultrasonic waves with multiple different phases.

[0127] Specifically, for example, the security level of the current application scenario can be detected first. When it is detected that the security level of the current application scenario is greater than a preset security level threshold, it can be determined that the current application scenario is an application scenario with relatively high accuracy requirements and multiple different ultrasonic waves need to be used simultaneously (for example, the bank identity verification scenario). Furthermore, it can be determined to use multiple different ultrasonic waves simultaneously to obtain target fingerprint data. On the contrary, when it is detected that the security level of the current application scenario is less than or equal to the preset security level threshold, it can be determined that the current application scenario is an application scenario with relatively low accuracy requirements and only needs to be quickly detected. Furthermore, it can be determined to use only one ultrasonic wave to obtain target fingerprint data.

[0128] For another example, a matching ultrasonic wave can be determined first, and target fingerprint data can be collected based on it; then, it can be detected whether the data quality of the target fingerprint data meets the preset quality requirements; in the case where it is determined that the data quality of the target fingerprint data does not meet the preset quality requirements, it can be determined to use multiple different ultrasonic waves simultaneously to re-acquire the target fingerprint data.

[0129] In some embodiments, referring to Figure 4 as shown, when the method is specifically implemented, the following content may further be included:

[0130] S1: Determine a matching target angle scanning range;

[0131] S2: According to the target angle scanning range, control the ultrasonic transducer to perform multi-angle scanning to obtain a plurality of first-type echo signals at different angles;

[0132] S3: Obtain target fingerprint data according to the plurality of first-type echo signals.

[0133] Specifically, in the case where it is determined to use multiple different ultrasonic waves simultaneously to obtain target fingerprint data, the required target fingerprint data can be obtained based on ultrasonic waves at multiple different angles.

[0134] First, a matching target angle scanning range can be determined according to the size of the detection object (such as a finger, etc.) pressed by the user on the fingerprint collection area. For example, it is greater than or equal to 0 degrees and less than or equal to 90 degrees. Among them, the target angle scanning range can cover the key area of the detection object.

[0135] Then, according to the target angle scanning range, at a preset step amplitude (such as 30 degrees), control the ultrasonic transducer to perform multi-angle scanning to obtain a plurality of first-type echo signals at different angles. For example, the first-type echo signal based on 30-degree ultrasonic wave, the first-type echo signal based on 60-degree ultrasonic wave, and the first-type echo signal based on 90-degree ultrasonic wave. Thus, a plurality of first-type echo signals for the same detection object obtained based on ultrasonic waves at different angles can be obtained. Among them, each first-type echo signal corresponds to an angle.

[0136] Furthermore, a plurality of first-type echo signals can be jointly used to construct target fingerprint data that can effectively reduce environmental noise and interference, has high reliability and accuracy, and can be applied to a variety of complex environmental conditions.

[0137] In some embodiments, for the above-mentioned obtaining target fingerprint data according to a plurality of first-type echo signals, when specifically implemented, the following content may be included:

[0138] S1: Based on multiple first - type echo signals, determine the depth information at multiple angles on the finger surface by calculating the signal propagation time;

[0139] S2: Extract corresponding signal parameters from multiple first - type echo signals; wherein, the signal parameters include at least one of the following: intensity, phase, and time delay;

[0140] S3: Use the depth information at multiple angles and the corresponding signal parameters, through data fusion, to obtain target fingerprint data.

[0141] In specific implementation, in the above - mentioned manner, depth information at multiple angles for the detection object and corresponding signal parameters can be extracted from multiple first - type echo signals; furthermore, based on corresponding algorithms, by comprehensively using the above - mentioned depth information and signal parameters, a high - resolution two - dimensional fingerprint image can be generated as the target fingerprint data; or a three - dimensional fingerprint image that is three - dimensional and has strong anti - interference ability can be constructed by fusing and using the above - mentioned depth information and signal parameter data as the target fingerprint data.

[0142] In some embodiments, the above - mentioned use of the depth information at multiple angles and the corresponding signal parameters, through data fusion, to obtain target fingerprint data, in specific implementation, may include the following:

[0143] S1: Perform alignment processing and calibration processing on the depth information at multiple angles respectively to obtain multiple processed depth information;

[0144] S2: According to the signal parameters, combine and use multiple processed depth information to construct a three - dimensional fingerprint image as the target fingerprint data.

[0145] In specific implementation, by performing alignment and calibration processing on the depth information at multiple angles respectively, the error caused by different scanning angles can be eliminated, so that the subsequent target fingerprint data with relatively smaller error can be constructed using the above - mentioned processed depth information.

[0146] In specific implementation, based on corresponding three - dimensional modeling algorithms, according to the signal parameters, combine and use multiple processed depth information for three - dimensional reconstruction to obtain the corresponding three - dimensional fingerprint image as the target fingerprint data.

[0147] In this way, the depth information based on different angles can be effectively utilized to optimize and enhance the fingerprint image, remove noise and errors, and improve the clarity and detail performance of the image. Thus, environmental noise and interference can be effectively reduced, the reliability and robustness of the image can be improved, and target fingerprint data that is applicable to a variety of different complex environmental conditions and has strong anti - interference ability can be obtained.

[0148] Correspondingly, when a user inputs a fingerprint, the user can also collect a plurality of first type echo signals through multi-angle scanning in the above manner, and then combine and use the plurality of first type echo signals to construct a user fingerprint feature template corresponding to the user, with relatively better effects.

[0149] In some embodiments, referring to Figure 5 as shown, when the method is specifically implemented, the following content may further be included:

[0150] S1: Determine a target frequency range and a target phase range that match;

[0151] S2: According to the target frequency range and the target phase range, control the ultrasonic transducer to perform multi-frequency and multi-phase scanning to obtain a plurality of second type echo signals;

[0152] S3: Obtain target fingerprint data according to the plurality of second type echo signals.

[0153] Specifically, in the case of determining to simultaneously use multiple different ultrasonic waves to obtain target fingerprint data, the required target fingerprint data can be obtained based on ultrasonic waves with multiple different frequencies and ranges.

[0154] When specifically implemented, the target frequency range and the target phase range that match can be determined according to the contact pressure information and / or the surface characteristic information of the finger.

[0155] When specifically implemented, according to the target frequency range and the target phase range, the ultrasonic transducer can be controlled to perform multi-frequency and multi-phase scanning to obtain a plurality of second type echo signals based on different frequencies and phases. Among them, each second type echo signal corresponds to one frequency and / or one phase. In this way, a plurality of second type echo signals that cover multiple frequencies and phases and are relatively rich and comprehensive can be obtained. Furthermore, by fusing and using the plurality of second type echo signals, target fingerprint data containing a large amount of detailed information can be constructed. Based on the above target fingerprint data, high-precision detection and recognition of fingerprints under complex environmental conditions can be realized.

[0156] Correspondingly, when a user inputs a fingerprint, the user can also collect a plurality of second type echo signals through multi-frequency and multi-phase scanning in the above manner, and then combine and use the plurality of second type echo signals to construct a user fingerprint feature template corresponding to the user, with relatively better effects.

[0157] In some embodiments, after collecting the target fingerprint data, when the method is specifically implemented, the following content may further be included: generating a corresponding target fingerprint image according to the target fingerprint data; performing fingerprint feature comparison according to the target fingerprint image and a preset user fingerprint feature template to obtain a target comparison result; and determining whether the fingerprint recognition passes according to the target comparison result.

[0158] In specific implementation, corresponding image processing algorithms can be utilized to generate a target fingerprint image containing the fingerprint feature information of the user based on the target fingerprint data; then, the target fingerprint image is used to perform fingerprint feature comparison with a preset user fingerprint feature template stored by the user during the fingerprint entry stage to obtain a corresponding target comparison result.

[0159] According to the target comparison result, when it is determined that the similarity of the fingerprint features between the two is greater than or equal to a preset similarity threshold, it can be determined that the fingerprint recognition is passed. Otherwise, it is determined that the fingerprint recognition fails.

[0160] As can be seen from the above, in the dynamic acquisition method of ultrasonic fingerprint data provided by the embodiments of this specification, in specific implementation, the contact pressure information of the current finger relative to the fingerprint acquisition area and / or the surface characteristic information of the finger can be obtained first; according to the contact pressure information and / or the surface characteristic information of the finger, the emission parameters of the ultrasonic wave are adjusted; based on the adjusted ultrasonic wave, the target fingerprint data is acquired. Thus, it is possible to determine and adaptively dynamically adjust the emission parameters of the ultrasonic wave according to the contact state of the finger, and then fingerprint data with fine surface features and small errors can be acquired based on the adjusted ultrasonic wave, so that subsequent fingerprint data processing such as fingerprint recognition can be accurately realized based on the fingerprint data.

[0161] The embodiments of this specification provide an electronic device, as shown in Figure 6 shown. Among them, the electronic device includes a network communication port 601, a processor 602, and a memory 603. The above structures are connected by internal cables so that each structure can perform specific data interaction.

[0162] Among them, the network communication port 601 can specifically be used to obtain the contact pressure information of the current finger relative to the fingerprint acquisition area and / or the surface characteristic information of the finger.

[0163] The processor 602 can specifically be used to adjust the emission parameters of the ultrasonic wave according to the contact pressure information and / or the surface characteristic information of the finger; based on the adjusted ultrasonic wave, the target fingerprint data is acquired.

[0164] The memory 603 can specifically be used to store corresponding instruction programs and related intermediate data.

[0165] Based on the above method, the relevant structural performance of the electronic device can be effectively utilized to improve the data processing speed of the electronic device and efficiently realize the data processing of the dynamic acquisition of ultrasonic fingerprint data.

[0166] In this embodiment, the network communication port 601 can be bound to different communication protocols, so as to send or receive different data through virtual ports. For example, the network communication port can be a port responsible for web data communication, or a port responsible for FTP data communication, or a port responsible for email data communication. In addition, the network communication port can also be a physical communication interface or communication chip. For example, it can be a wireless mobile network communication chip, such as GSM, CDMA, etc.; it can also be a Wifi chip; it can also be a Bluetooth chip.

[0167] In this embodiment, the processor 602 can be implemented in any suitable manner. For example, the processor can be in the form of, for example, a microprocessor or a processor, and a computer-readable medium storing computer-readable program code (such as software or firmware) executable by the (micro)processor, logic gates, switches, an application specific integrated circuit (ASIC), a programmable logic controller, and an embedded microcontroller, etc. This specification does not make any limitations.

[0168] In this embodiment, the memory 603 can include multiple levels. In a digital system, anything that can store binary data can be a memory; in an integrated circuit, a circuit with a storage function without a physical form is also called a memory, such as RAM, FIFO, etc.; in a system, a storage device with a physical form is also called a memory, such as a memory stick, a TF card, etc.

[0169] This embodiment of the specification also provides a computer-readable storage medium for a dynamic acquisition method based on the above ultrasonic fingerprint data. The computer-readable storage medium stores computer program instructions, and when the computer program instructions are executed, the following steps are implemented: obtaining contact pressure information of the current finger relative to the fingerprint acquisition area and / or surface characteristic information of the finger; adjusting the emission parameters of the ultrasonic wave according to the contact pressure information and / or the surface characteristic information of the finger; and acquiring target fingerprint data based on the adjusted ultrasonic wave.

[0170] In this embodiment, the above storage medium includes but is not limited to a random access memory (RAM), a read-only memory (ROM), a cache, a hard disk drive (HDD), or a memory card. The memory can be used to store computer program instructions. The network communication unit can be set according to the standards specified by the communication protocol and is an interface for network connection communication.

[0171] In this embodiment, the functions and effects specifically realized by the program instructions stored in the computer-readable storage medium can be explained by comparison with other embodiments, and will not be elaborated here.

[0172] An embodiment of this specification also provides a computer program product, which at least includes a computer program. When the computer program is executed by a processor, the following method steps are implemented: obtaining contact pressure information of the current finger relative to the fingerprint acquisition area and / or surface characteristic information of the finger; adjusting the emission parameters of ultrasonic waves according to the contact pressure information and / or the surface characteristic information of the finger; collecting target fingerprint data based on the adjusted ultrasonic waves.

[0173] Refer to Figure 7 As shown, an embodiment of this specification also provides a dynamic acquisition device for ultrasonic fingerprint data. The device may specifically include the following structural modules:

[0174] An acquisition module 701, which may specifically be used to obtain contact pressure information of the current finger relative to the fingerprint acquisition area and / or surface characteristic information of the finger;

[0175] An adjustment module 702, which may specifically be used to adjust the emission parameters of ultrasonic waves according to the contact pressure information and / or the surface characteristic information of the finger;

[0176] A collection module 703, which may specifically be used to collect target fingerprint data based on the adjusted ultrasonic waves.

[0177] In some embodiments, the ultrasonic waves may specifically include focused waves;

[0178] Correspondingly, the emission parameters of the ultrasonic waves may specifically include: frequency and / or phase, etc.

[0179] In some embodiments, the ultrasonic waves may specifically include plane waves;

[0180] Correspondingly, the emission parameters of the ultrasonic waves may specifically include: frequency, etc.

[0181] In some embodiments, the surface characteristic information may specifically include at least one of the following: roughness, smoothness, humidity, etc.

[0182] In some embodiments, when the adjustment module 702 is specifically implemented, the emission parameters of the ultrasonic waves may be adjusted according to the contact pressure information and / or the surface characteristic information of the finger in the following manner: when the contact pressure indicated by the contact pressure information is greater than a preset first pressure threshold, the frequency of the ultrasonic waves is reduced according to a first adjustment rule; when the contact pressure indicated by the contact pressure information is less than a preset second pressure threshold, the frequency of the ultrasonic waves is increased according to the first adjustment rule; where the preset first pressure threshold is greater than the preset second pressure threshold.

[0183] In some embodiments, when the adjustment module 702 is specifically implemented, the transmission parameters of the ultrasonic wave can be adjusted according to the contact pressure information and / or the surface characteristic information of the finger in the following manner: when the roughness of the finger indicated by the surface characteristic information is greater than a preset first roughness threshold, the phase of the ultrasonic wave is increased according to a second adjustment rule; when the roughness of the finger indicated by the surface characteristic information is less than a preset second roughness threshold, the phase of the ultrasonic wave is decreased according to the second adjustment rule; wherein, the preset first roughness threshold is greater than the preset second roughness threshold.

[0184] In some embodiments, when the adjustment module 702 is specifically implemented, the transmission parameters of the ultrasonic wave can be adjusted according to the contact pressure information and / or the surface characteristic information of the finger in the following manner: when the humidity of the finger indicated by the surface characteristic information is greater than a preset first humidity threshold, the frequency of the ultrasonic wave is decreased according to a third adjustment rule; when the humidity of the finger indicated by the surface characteristic information is less than a preset second humidity threshold, the frequency of the ultrasonic wave is increased according to the third adjustment rule; wherein, the preset first humidity threshold is greater than the preset second humidity threshold.

[0185] In some embodiments, when the above device is specifically implemented, it can also be used for: determining a matching target angle scanning range; controlling an ultrasonic transducer to perform multi-angle scanning according to the target angle scanning range to obtain a plurality of first-type echo signals at different angles; and obtaining target fingerprint data according to the plurality of first-type echo signals.

[0186] In some embodiments, when the above device is specifically implemented, the target fingerprint data can be obtained according to the plurality of first-type echo signals in the following manner: according to the plurality of first-type echo signals, the depth information at multiple angles on the finger surface is determined by calculating the signal propagation time; according to the plurality of first-type echo signals, the corresponding signal parameters are extracted; wherein, the signal parameters include at least one of the following: intensity, phase, and time delay; using the depth information at multiple angles and the corresponding signal parameters, the target fingerprint data is obtained through data fusion.

[0187] In some embodiments, when the above device is specifically implemented, the target fingerprint data can be obtained through data fusion by using the depth information at multiple angles and the corresponding signal parameters in the following manner: the depth information at multiple angles is respectively subjected to alignment processing and calibration processing to obtain a plurality of processed depth information; according to the signal parameters, the plurality of processed depth information is combined to construct a three-dimensional fingerprint image as the target fingerprint data.

[0188] In some embodiments, when the above device is specifically implemented, it can also be used to: determine a matching target frequency range and a target phase range; control an ultrasonic transducer to perform multi-frequency and multi-phase scanning according to the target frequency range and the target phase range to obtain a plurality of second echo signals; and obtain target fingerprint data according to the plurality of second echo signals.

[0189] It should be noted that the units, devices, modules, etc. described in the above embodiments can be specifically implemented by computer chips or entities, or by products with certain functions. For the convenience of description, when describing the above device, it is divided into various modules according to functions and described separately. Of course, when implementing this specification, the functions of each module can be implemented in one or more software and / or hardware, or the modules implementing the same function can be implemented by a combination of multiple sub-modules or sub-units. The device embodiments described above are merely illustrative. For example, the division of the units is only a logical function division, and there may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed coupling or direct coupling or communication connection to each other can be through some interfaces, and the indirect coupling or communication connection of the devices or units can be in electrical, mechanical or other forms.

[0190] As can be seen from the above, based on the ultrasonic fingerprint data dynamic acquisition device provided in the embodiments of this specification, it is possible to determine and adaptively adjust the ultrasonic emission parameters according to the contact state of the finger, and then can collect fingerprint data with fine surface features and small errors based on the adjusted ultrasonic waves, so as to accurately implement subsequent fingerprint data processing such as fingerprint recognition based on the fingerprint data.

[0191] In a specific scenario example, the ultrasonic fingerprint data dynamic acquisition method provided in this specification can be applied to implement high-precision focused wave ultrasonic fingerprint detection. The specific implementation process can refer to the following content.

[0192] In this scenario example, considering that the existing ultrasonic fingerprint detection methods have certain limitations in detail capture and resolution, it is difficult to obtain high-precision fingerprint images. Usually only single-angle detection is performed, and it is difficult to capture comprehensive fingerprint features. When performing high-resolution detection, the frame rate is slow and the power consumption is high, which affects the user experience of fingerprint unlocking of portable devices.

[0193] In view of the above problems and their root causes, in this scenario example, further considerations are as follows. First, an adaptive control system can be introduced to dynamically adjust the emission frequency and phase of the focused wave according to the finger contact pressure and surface characteristics, thereby improving the detection accuracy and reliability. Second, multi-dimensional focused wave scanning can be performed to conduct high-resolution fingerprint detection from multiple angles and directions, generating a more comprehensive and detailed fingerprint image. In addition, the finger area can be determined quickly by plane wave detection, and then the focused wave can be used for high-precision detection, improving the detection speed and optimizing power consumption.

[0194] During specific implementation, in terms of the hardware structure, the key modules involved in the hardware architecture include an adaptive focused wave control module, a pressure sensor, a surface characteristics sensor, an adaptive control unit, a plane wave transmitter, and a receiver.

[0195] The mutual positions and connection relationships of these modules can be described as follows: Pressure sensor and surface characteristics sensor: Installed below or around the fingerprint detection area to monitor the finger contact pressure and surface characteristics in real time. The signals of these sensors are connected to the adaptive control unit through a data bus. Adaptive control unit: Located in the core part of the system, it receives data from the pressure sensor and the surface characteristics sensor, performs real-time calculations, and dynamically adjusts the emission frequency and phase of the focused wave. The adaptive control unit is connected to the adaptive focused wave control module through a high-speed communication interface. Adaptive focused wave control module: This module is connected to multiple ultrasonic transducers and is responsible for adjusting the emission frequency and phase of each transducer according to the instructions of the adaptive control unit. It conducts signal transmission and control through a low-latency digital signal processing chip. Plane wave transmitter and receiver: Used for preliminary detection of the finger pressing area. The transmitter and receiver are usually located on the periphery of the fingerprint detection area to cover the entire fingerprint detection area. The transmitter emits plane waves to the finger surface, and the receiver captures the reflected signals, which are connected to the adaptive control unit through a signal bus.

[0196] In terms of the control method, when the system starts, the plane wave transmitter and receiver are initialized first, setting the initial ultrasonic emission frequency (e.g., 5 MHz) and phase (e.g., 0°). At the same time, the pressure sensor and the surface characteristics sensor start to monitor the finger contact pressure (e.g., within the range of 0.1 N - 1 N) and surface roughness.

[0197] First, plane wave detection can be used for quick detection. Among them, the plane wave transmitter emits plane waves covering the entire fingerprint detection area at a low frequency (e.g., 5 MHz), and the receiver captures the reflected signals to preliminarily determine the area where the finger presses. Among them, the criterion for preliminary area judgment can be whether the signal reflection time and intensity exceed the set threshold (e.g., signal intensity > 50 dB).

[0198] Then, perform adaptive focused wave emission. Specifically, after initially determining the area, the adaptive control unit adjusts the emission frequency of the focused wave according to the data of the pressure sensor (for example, when the pressure is high, the emission frequency is adjusted to 10 MHz to improve penetration) and the phase (for example, adjusts the phase according to the roughness of the surface property sensor to ensure signal consistency). Among them, the emission parameters (frequency, phase, emission intensity) of each ultrasonic transducer will also be dynamically adjusted to ensure that the focused wave can be efficiently concentrated in the fingerprint feature area.

[0199] Among them, the focused wave emission frequency: Usually, it can be set between 5 MHz and 20 MHz and can be dynamically adjusted according to the finger contact pressure and surface properties. The focused wave emission phase: Compensates for the signal difference between the surface properties and the transducer through phase adjustment, and the adjustment range can be between 0° and 360°. The transducer emission parameters: The emission intensity of each transducer can be dynamically adjusted according to the received reflected signal to ensure that the energy of the focused wave is concentrated in the area most in need of detection.

[0200] Specifically, the pressure when the finger presses on the sensor surface directly affects the propagation path of the ultrasonic wave and the quality of the signal. Excessive pressure will cause excessive reflection or transmission of the signal, affecting the clarity of the image; too little pressure will result in insufficient contact and insufficient signal. By detecting the pressing force in real time through the pressure sensor, the system can dynamically adjust the emission parameters of the focused wave to adapt to different contact pressures. Low-pressure situation (for example, less than 0.2 N): When the pressure sensor detects that the finger pressing force is small and the contact is insufficient, the system will reduce the emission frequency of the ultrasonic wave (for example, from 8 MHz to 5 MHz) to reduce signal transmission and reflection losses and ensure that enough signals can be captured for imaging. High-pressure situation (for example, greater than 0.8 N): When the pressure is high, the system will increase the emission frequency (for example, from 5 MHz to 8 MHz or higher) to ensure that the ultrasonic wave has sufficient penetration and avoid signal distortion caused by pressing the finger too tightly.

[0201] Specifically, the roughness of the finger surface will affect the reflection characteristics of the ultrasonic wave. Especially when the surface is not smooth or affected by sweat, etc., the reflected signal is prone to phase deviation. By detecting the humidity and roughness of the surface through the surface property sensor, the system can dynamically adjust the phase of the focused wave to reduce noise interference and improve signal consistency. High-roughness situation: When the surface roughness is high (for example, the detected roughness value is greater than the preset threshold of 1.5), the system will increase the phase compensation angle (for example, from 0° to 45°) to avoid image blurring caused by signal deviation. Low-roughness situation: If the surface is smooth and there is no obvious interference such as sweat (for example, the roughness is less than the preset threshold of 0.5), the system can reduce the phase compensation (for example, maintain at 0° or only adjust to 10°) to maintain the accuracy and consistency of the signal.

[0202] Furthermore, according to specific circumstances, multi-angle focused wave scanning can also be performed. For example, the focused wave can perform multi-angle scanning at multiple angles (such as 0°, 30°, 60°, etc.) within a determined area. Specifically, at different angles, the system captures the intensity, phase, and time delay of the reflected signal. By calculating the signal propagation time, the depth information of different points on the finger surface is determined. Then, through data fusion and processing, the depth information captured at different angles is fused. Algorithms are used to calibrate the errors and generate a two-dimensional high-resolution fingerprint image. Finally, three-dimensional reconstruction is performed using multi-dimensional scanning data to generate a three-dimensional fingerprint image for comparison and identification. Among them, the angle range of multi-angle scanning: usually the scanning angle is between 0° and 90°, increasing by 30°, and more refined angle adjustments can be made according to needs.

[0203] Specific implementation can include the following specific steps:

[0204] 1. Fast detection of plane waves: Used to quickly emit plane waves to cover a large-area fingerprint detection region, receive the reflected signal, and preliminarily determine the finger pressing area.

[0205] a) Initialization: When the system starts, the plane wave transmitter and receiver are initialized, and the initial ultrasonic emission frequency and phase are set.

[0206] b) Signal emission: The plane wave emission covers the entire fingerprint acquisition region to ensure quick detection of the presence of the finger, with low power consumption.

[0207] c) Signal reception and processing: The receiver captures the reflected ultrasonic signal and performs preliminary processing (such as preprocessing); among them, the preliminary processing includes signal filtering and noise suppression to ensure that the detected signal is clear.

[0208] d) Preliminary area determination: Through the processed signal, the system can quickly determine the finger pressing area and send information to the adaptive focused wave control module.

[0209] 2. Adaptive focused wave control: By using a pressure sensor to monitor the finger contact pressure in real time and a surface characteristic sensor to detect the roughness and humidity of the finger surface, etc., the emission frequency and phase of the focused wave are dynamically adjusted.

[0210] a) Initialization and monitoring: When the system is initialized, the pressure sensor and the surface characteristic sensor start to monitor the finger pressing pressure and surface characteristics. These data are sent to the adaptive control unit in real time.

[0211] b) Dynamic parameter adjustment: The adaptive control unit dynamically adjusts the emission frequency and phase of the focused wave based on sensor data. For example, when the finger contact pressure is high, higher frequency and intensity focused waves may be required to ensure penetration and detection accuracy; when the finger surface roughness is high, the phase may need to be adjusted to improve signal consistency.

[0212] c) High-precision emission: The adjusted focused wave is concentrated and emitted to the detected finger contact area, improving the detection accuracy and resolution. By adjusting the emission parameters of each transducer, the emission direction and energy concentration point of the ultrasonic transducer can be precisely controlled to achieve dynamic scanning of the focused wave.

[0213] d) Multi-frequency and multi-phase control: The system can simultaneously control the emission of ultrasonic waves at multiple frequencies and phases to achieve high-precision detection in complex environments. For example, the system can simultaneously emit high-frequency and low-frequency focused waves to capture fingerprint features at different depths.

[0214] 3. Multi-dimensional focused wave scanning: Achieve multi-angle focused wave scanning of different areas of the finger to capture more fingerprint details. Combine multi-dimensional scanning data and generate a three-dimensional fingerprint image through algorithms to improve recognition accuracy.

[0215] a) Multi-angle scanning: After initialization, the system starts to perform multi-angle focused wave scanning on the finger. These angles include different emission angles and incident angles to ensure that more details on the finger surface are captured.

[0216] b) Data capture and processing: At each angle, the system captures the reflected focused wave signal and performs preliminary processing. This data includes the intensity, phase, and time delay of the reflected signal, etc. By calculating the propagation time of each signal, the depth information of different points on the finger surface can be determined.

[0217] c) Data fusion: Align and calibrate the depth information obtained from different angles to eliminate errors caused by different scanning angles. Use algorithms to generate a high-resolution two-dimensional fingerprint image to ensure the accuracy of the image.

[0218] d) 3D imaging: Reconstruct the data from multiple scans through algorithms to generate a three-dimensional fingerprint image. This process utilizes the depth information from different angles, optimizes and enhances the generated three-dimensional fingerprint image, removes noise and errors, and improves the clarity and detail performance of the image.

[0219] e) Fingerprint matching and recognition: Match and recognize the three-dimensional fingerprint image with a pre-stored fingerprint database, and improve the accuracy and security of recognition by comparing three-dimensional fingerprint features.

[0220] Through the above scenario examples, the dynamic acquisition method of ultrasonic fingerprint data provided in this specification is verified. By introducing and using a pressure sensor and a surface characteristic sensor, the emission parameters of the focused wave can be adjusted in real time, including frequency and phase adaptive adjustment, improving the detection accuracy and reliability; through multi-angle focused wave scanning, more fingerprint details can be captured to generate high-resolution and three-dimensional fingerprint images; and plane waves are also used for rapid area detection, and then focused waves are used for high-precision detection to improve the detection speed and optimize power consumption.

[0221] Although this specification provides method operation steps as described in the embodiments or flowcharts, more or fewer operation steps may be included based on conventional or non-creative means. The step sequences listed in the embodiments are only one of the many ways of the execution sequences of the steps and do not represent the only execution sequence. When the actual device or client product is executed, it can be executed in the method sequence shown in the embodiments or the drawings or executed in parallel (for example, in an environment of parallel processors or multi-threaded processing, or even in a distributed data processing environment). The term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, product or device comprising a series of elements not only includes those elements but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, product or device. Without further limitation, the presence of additional identical or equivalent elements in the process, method, product or device comprising the said elements is not excluded. The words such as first, second, etc. are used to denote names and do not denote any particular order.

[0222] Those skilled in the art also know that in addition to implementing the controller in the form of pure computer-readable program code, the method steps can be logically programmed to enable the controller to be implemented in the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers, embedded microcontrollers, etc. to achieve the same function. Therefore, such a controller can be regarded as a hardware component, and the devices included therein for implementing various functions can also be regarded as the structures within the hardware component. Or even, the devices for implementing various functions can be regarded as both software modules for implementing the method and the structures within the hardware component.

[0223] This specification can be described in the general context of computer-executable instructions executed by a computer, such as program modules. Generally, program modules include routines, programs, objects, components, data structures, classes, etc. that perform specific tasks or implement specific abstract data types. This specification can also be practiced in a distributed computing environment where tasks are performed by remote processing devices connected through a communication network. In a distributed computing environment, program modules can be located in local and remote computer-readable storage media including storage devices.

[0224] As can be seen from the description of the above embodiments, those skilled in the art can clearly understand that this specification can be implemented by means of software plus a necessary general hardware platform. Based on such an understanding, the technical solution of this specification can essentially be embodied in the form of a software product, and this computer software product can be stored in a storage medium, such as ROM / RAM, magnetic disk, optical disc, etc., including several instructions for causing a computer device (which can be a personal computer, a mobile terminal, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments of this specification.

[0225] The embodiments in this specification are described in a progressive manner. For the same or similar parts between the embodiments, reference can be made to each other. The key point of each embodiment is to illustrate the differences from other embodiments. This specification can be used in many general or special computer system environments or configurations. For example: personal computers, server computers, handheld or portable devices, tablet devices, multi-processor systems, microprocessor-based systems, set-top boxes, programmable electronic devices, network PCs, minicomputers, mainframe computers, distributed computing environments including any of the above systems or devices, and so on.

[0226] Although this specification is depicted through embodiments, those of ordinary skill in the art know that this specification has many deformations and changes without departing from the spirit of this specification. It is hoped that the appended claims will cover these deformations and changes without departing from the spirit of this specification.

Claims

1. A dynamic acquisition method for ultrasonic fingerprint data, characterized in that Including: Obtaining contact pressure information of the current finger relative to the fingerprint acquisition area and / or surface characteristic information of the finger; Adjusting the emission parameters of the ultrasonic wave according to the contact pressure information and / or the surface characteristic information of the finger; Collecting target fingerprint data based on the adjusted ultrasonic wave.

2. The method according to claim 1, wherein The ultrasonic wave includes a focused wave and / or a plane wave; Correspondingly, the emission parameters of the ultrasonic wave include: frequency and / or phase.

3. The method according to claim 2, wherein The surface characteristic information includes at least one of the following: roughness, smoothness, humidity.

4. The method according to claim 1, wherein Adjusting the emission parameters of the ultrasonic wave according to the contact pressure information and / or the surface characteristic information of the finger includes: When the contact pressure indicated by the contact pressure information is greater than a preset first pressure threshold, reducing the frequency of the ultrasonic wave according to a first adjustment rule; When the contact pressure indicated by the contact pressure information is less than a preset second pressure threshold, increasing the frequency of the ultrasonic wave according to a first adjustment rule; wherein, the preset first pressure threshold is greater than the preset second pressure threshold.

5. The method according to claim 3, wherein Adjusting the emission parameters of the ultrasonic wave according to the contact pressure information and / or the surface characteristic information of the finger includes: When the roughness of the finger indicated by the surface characteristic information is greater than a preset first roughness threshold, increasing the phase of the ultrasonic wave according to a second adjustment rule; When the roughness of the finger indicated by the surface characteristic information is less than a preset second roughness threshold, reducing the phase of the ultrasonic wave according to a second adjustment rule; wherein, the preset first roughness threshold is greater than the preset second roughness threshold.

6. The method according to claim 3, wherein Adjusting the emission parameters of the ultrasonic wave according to the contact pressure information and / or the surface characteristic information of the finger includes: When the humidity of the finger indicated by the surface characteristic information is greater than a preset first humidity threshold, reducing the frequency of the ultrasonic wave according to a third adjustment rule; When the humidity of the finger indicated by the surface characteristic information is less than a preset second humidity threshold, increasing the frequency of the ultrasonic wave according to a third adjustment rule; wherein, the preset first humidity threshold is greater than the preset second humidity threshold.

7. The method according to claim 1, characterized in that, The method further includes: Determining a target angle scanning range that matches; Controlling an ultrasonic transducer to perform multi-angle scanning according to the target angle scanning range to obtain a plurality of first type echo signals at different angles; Obtaining target fingerprint data according to the plurality of first type echo signals.

8. The method according to claim 7, wherein Obtaining target fingerprint data according to the plurality of first type echo signals includes: Determining depth information at multiple angles on the finger surface by calculating the signal propagation time according to the plurality of first type echo signals; Extracting corresponding signal parameters according to the plurality of first type echo signals; wherein, the signal parameters include at least one of the following: intensity, phase, and time delay; Using the depth information at multiple angles and the corresponding signal parameters, obtaining target fingerprint data through data fusion.

9. The method according to claim 8, wherein Using the depth information at multiple angles and the corresponding signal parameters, obtaining target fingerprint data through data fusion includes: Performing alignment processing and calibration processing on the depth information at multiple angles respectively to obtain a plurality of processed depth information; Combining multiple processed depth information according to signal parameters to construct a three-dimensional fingerprint image as the target fingerprint data.

10. The method according to claim 1, wherein The method further includes: Determining a matching target frequency range and a target phase range; Controlling an ultrasonic transducer to perform multi-frequency and multi-phase scanning according to the target frequency range and the target phase range to obtain a plurality of second-type echo signals; Obtaining target fingerprint data according to the plurality of second-type echo signals.

11. A dynamic acquisition device for ultrasonic fingerprint data, characterized in that, Including: An acquisition module for acquiring contact pressure information of the current finger relative to the fingerprint acquisition area and / or surface characteristic information of the finger; An adjustment module for adjusting the transmission parameters of the ultrasonic wave according to the contact pressure information and / or the surface characteristic information of the finger; An acquisition module for acquiring target fingerprint data based on the adjusted ultrasonic wave.

12. An electronic device, characterized in that, Including a processor and a memory for storing instructions executable by the processor, and the processor implements the steps of the method according to any one of claims 1 to 10 when executing the instructions.

13. A computer-readable storage medium, characterized in that, Stored thereon are computer instructions, and when the instructions are executed by a processor, the steps of the method according to any one of claims 1 to 10 are implemented.

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