WO2020102945A1

WO2020102945A1 - Fingerprint identification method, apparatus and electronic device

Info

Publication number: WO2020102945A1
Application number: PCT/CN2018/116234
Authority: WO
Inventors: 蒋鹏
Original assignee: 深圳市汇顶科技股份有限公司
Priority date: 2018-11-19
Filing date: 2018-11-19
Publication date: 2020-05-28
Also published as: CN109643379A; CN109643379B

Abstract

A fingerprint identification method, apparatus and electronic device, which may improve the security of fingerprint identification. The method comprises: collecting at least one fingerprint image of an object to be identified when the object to be identified presses at least one predetermined pattern in a fingerprint detection zone of a display screen, wherein each fingerprint image corresponds to a predetermined pattern, and the strength of an optical signal corresponding to a first zone in the predetermined pattern is greater than the strength of an optical signal corresponding to a second zone in the predetermined pattern (510); determining a first target image and/or a second target image according to the at least one fingerprint image, the first target image comprising an image formed by an optical signal that is reflected at a surface of the object to be identified by the optical signal corresponding to the at least one predetermined pattern, and the second target image comprising an image formed by an optical signal scattered at the interior of the object to be identified by the optical signal corresponding to the at least one predetermined pattern (520); and determining according to the first target image and/or the second target image whether the object to be identified is a real finger (530).

Description

Fingerprint identification method, device and electronic equipment

Technical field

The present application relates to the field of fingerprint identification technology, and more specifically, to a fingerprint identification method, device, and electronic device.

Background technique

The application of optical fingerprint recognition devices brings users a safe and convenient user experience, but forged fingerprints such as fingerprint molds made of artificial materials (such as silicone, white glue, etc.) are a security risk in fingerprint applications. By forging fingerprints A fingerprint image with a high degree of similarity to a real fingerprint can be obtained. Therefore, how to identify the true and false fingerprints collected by the optical fingerprint recognition device to improve the security of fingerprint recognition is an urgent problem to be solved.

Summary of the invention

Embodiments of the present application provide a fingerprint identification method, device, and electronic equipment, which can effectively identify true and false fingerprints and improve the security of fingerprint identification.

In a first aspect, a fingerprint recognition method is provided, which includes: when an object to be recognized presses at least one predetermined pattern sequentially displayed on a fingerprint detection area of a display screen, collecting at least one fingerprint image of the object to be recognized, wherein each Each fingerprint image corresponds to a predetermined pattern, and the intensity of the optical signal corresponding to the first area in the predetermined pattern is greater than the intensity of the optical signal corresponding to the second area in the predetermined pattern; based on the at least one fingerprint image, the A target image and / or a second target image, wherein the first target image includes an image formed by the optical signal reflected by the optical signal corresponding to the at least one predetermined pattern on the surface of the object to be identified, the second The target image is an image formed by the optical signal scattered by the optical signal corresponding to the at least one predetermined pattern inside the object to be identified; based on the first target image and / or the second target image, the target image is determined Identify whether the object is a real finger.

In some possible implementation manners, the at least one predetermined pattern includes a plurality of predetermined patterns, and when the object to be recognized presses the at least one predetermined pattern sequentially displayed on the fingerprint detection area of the display screen, the At least one fingerprint image includes: sequentially displaying each of the plurality of predetermined patterns in the fingerprint detection area of the display screen; and collecting a corresponding one of the fingerprint images based on each predetermined pattern.

In some possible implementations, the multiple predetermined patterns are obtained by phase shifting the same pattern, and the superimposed pattern of the multiple predetermined patterns is a single color pattern.

In some possible implementation manners, the plurality of predetermined patterns include a first predetermined pattern and a second predetermined pattern, and the fingerprint detection area of the display screen sequentially displays each of the plurality of predetermined patterns Including: controlling to turn on only the optical signal in the area where the fingerprint ridge pattern in the target fingerprint image is located to display the first predetermined pattern; or controlling to only turn on the optical signal in the area where the fingerprint valley pattern in the target fingerprint image is located To form the second predetermined pattern; wherein the target fingerprint image is a fingerprint image collected based on a predetermined pattern of a single color.

In some possible implementations, the plurality of predetermined patterns are a plurality of stripe patterns or a plurality of checkerboard patterns.

In some possible implementation manners, the determining the first target image and / or the second target image based on the at least one fingerprint image includes: multiple fingerprint images corresponding to the multiple fringe images, and the The phase relationship of multiple fringe images determines the first target image and / or the second target image.

In some possible implementation manners, the determining the first target image and / or the second target image based on the at least one fingerprint image includes:

Extracting the fingerprint information of the bright area and the fingerprint information of the dark area of each fingerprint image in the plurality of fingerprint images, wherein the bright area of each fingerprint image is the first of a predetermined pattern corresponding to the fingerprint image The imaging area of the light signal reflected by the area, the dark light area of each fingerprint image is the imaging area of the light signal reflected by the second area of the predetermined pattern corresponding to each fingerprint image; according to the The fingerprint information of the bright light area and the fingerprint information of the dark light area determine the first target image and / or the second target image, wherein the fingerprint information of the bright light area of the fingerprint image includes a predetermined corresponding to the fingerprint image The fingerprint information carried by the optical signal reflected by the light signal corresponding to the pattern on the surface of the object to be recognized and the fingerprint information carried by the optical signal scattered by the light signal corresponding to the predetermined pattern corresponding to the fingerprint image inside the object to be recognized .

In some possible implementation manners, the determining whether the object to be identified is a real finger according to the first target image and / or the second target image includes: according to the first target image and / or The second target image and the reference fingerprint image determine a first scale and / or a second scale, wherein the reference fingerprint image corresponds to a predetermined pattern of a single color; according to the first scale and / or the second scale Ratio to determine whether the object to be recognized is a real finger.

In some possible implementation manners, the determining the first ratio and / or the second ratio based on the first target image and / or the second target image and the reference fingerprint image includes: determining the reference fingerprint The first average value of the sample value of each pixel in the image; the ratio of the second average value of the sample value of all pixels in the first target image to the first average value is determined as the first A ratio; and / or determine the ratio of the third average value of the sampling values of all pixels in the second target image to the first average value as the second ratio.

In some possible implementation manners, the determining whether the object to be identified is a real finger according to the first ratio and / or the second ratio includes: if the first ratio is within a first preset range And / or the second ratio is within a second preset range, determining that the object to be recognized is a real finger.

In some possible implementations, the at least one predetermined pattern is formed by an optical signal emitted by a light source in the fingerprint detection area, where the light source includes at least one of a red light source, a green light source, and a blue light source.

In some possible implementations, the light source is a partial self-luminous display unit of the display screen in the fingerprint detection area, and the red light source, the green light source, and the blue light source are the display, respectively The red display unit, green display unit and blue display unit of the screen.

In some possible implementations, the method further includes: controlling to turn on the self-luminous display unit in the first area of the fingerprint detection area, and turning off the self-luminous display unit in the second area to form a Each predetermined pattern of the at least one predetermined pattern.

In some possible implementations, the wavelength of the corresponding optical signal of the pattern in the first area is the center wavelength of the optical fingerprint sensor used for fingerprint collection.

According to a second aspect, there is provided a fingerprint recognition device comprising: an optical fingerprint sensor for collecting at least one object to be recognized when the object to be recognized presses at least one predetermined pattern sequentially displayed on the fingerprint detection area of the display screen Fingerprint images, each fingerprint image corresponding to a predetermined pattern, wherein the intensity of the optical signal corresponding to the first area in the predetermined pattern is greater than the intensity of the optical signal corresponding to the second area in the predetermined pattern; wherein, the At least one fingerprint image is used to determine a first target image and / or a second target image, the first target image and / or the second target image is used to determine whether the object to be recognized is a real finger, the first A target image includes an image of an optical signal reflected by the optical signal corresponding to the at least one predetermined pattern on the surface of the object to be recognized, and the second target image includes an optical signal corresponding to the at least one predetermined pattern at the An image formed by light signals scattered inside the object to be identified.

In some possible implementation manners, the at least one predetermined pattern includes a plurality of predetermined patterns, and the optical fingerprint sensor is specifically configured to: sequentially display each of the plurality of predetermined patterns in a fingerprint detection area of the display screen When the pattern is predetermined, a corresponding fingerprint image is collected based on each predetermined pattern.

In some possible implementation manners, the plurality of predetermined patterns include a first predetermined pattern and a second predetermined pattern, the first area in the first predetermined pattern is the area where the fingerprint ridge pattern in the target fingerprint image is located, the The second area in the first predetermined pattern is the area where the fingerprint valley pattern in the target fingerprint image is located, the first area in the second predetermined pattern is the area where the fingerprint valley pattern in the target fingerprint image is located, the The second area in the second predetermined pattern is an area where the fingerprint ridge pattern in the target fingerprint image is located, wherein the target fingerprint image is a fingerprint image collected based on a predetermined pattern of a single color.

In some possible implementation manners, the fingerprint identification device further includes: a processor, configured to determine a fingerprint based on a plurality of fingerprint images corresponding to the plurality of stripe images and a phase relationship between the plurality of stripe images The first target image and / or the second target image.

In some possible implementation manners, the processor is further configured to: extract fingerprint information of a bright light area and fingerprint information of a dark light area of each fingerprint image in the plurality of fingerprint images, wherein each fingerprint The bright area of the image is the imaging area of the light signal reflected by the first area of the predetermined pattern corresponding to the fingerprint image, and the dark area of each fingerprint image is the second area of the predetermined pattern corresponding to each fingerprint image The imaging area of the reflected optical signal;

Determining the first target image and / or the second target image according to the fingerprint information of the bright area and the fingerprint information of the dark area of each fingerprint image, wherein the fingerprint information of the bright area of the fingerprint image Including the fingerprint information carried by the optical signal corresponding to the predetermined pattern corresponding to the fingerprint image on the surface of the object to be identified and the optical signal corresponding to the predetermined pattern corresponding to the fingerprint image to be scattered inside the object to be identified The fingerprint information carried by the optical signal.

In some possible implementations, the processor is further configured to determine the first ratio and / or the second ratio based on the first target image and / or the second target image and the reference fingerprint image, wherein , The reference fingerprint image corresponds to a predetermined pattern of a single color; according to the first scale and / or the second scale, it is determined whether the object to be recognized is a real finger.

In some possible implementation manners, the processor is further configured to: determine a first average value of the sampled value of each pixel in the reference fingerprint image; compare all pixels in the first target image The ratio of the second average value of the sampled values to the first average value is determined as the first ratio; and / or the third average value of the sampled values of all pixels in the second target image and the The ratio of the first average value is determined as the second ratio.

In some possible implementation manners, the processor is further configured to: if the first ratio is within a first preset range, and / or the second ratio is within a second preset range, determine the pending Recognize objects as real fingers.

In some possible implementations, the device further includes: a light source driving module for controlling to turn on the self-luminous display unit in the first area of the fingerprint detection area and turn off the self-luminous light in the second area The display unit to form each predetermined pattern.

In a third aspect, an electronic device is provided, including the fingerprint recognition device in the second aspect or any possible implementation manner of the second aspect.

Therefore, in the embodiment of the present application, the fingerprint recognition device may collect a corresponding fingerprint image according to a predetermined pattern with light and dark differences, and may further determine the light signal reflected from the surface of the object to be recognized and the light scattered from the object according to the fingerprint image The image formed by the signal can determine whether the object to be recognized is a real finger according to the characteristics of the two parts of the optical signal, thereby improving the security of fingerprint recognition.

BRIEF DESCRIPTION

FIG. 1 is a schematic plan view of an electronic device to which this application can be applied.

Fig. 2 is a schematic partial cross-sectional view of the electronic device shown in Fig. 1 along A-A '.

FIG. 3 is a schematic diagram of a fingerprint identification device according to an embodiment of the present application.

4 is a schematic diagram of several predetermined patterns according to an embodiment of the present application.

5 is a schematic flowchart of a fingerprint identification method according to an embodiment of the present application.

6 is a schematic diagram of a fingerprint image collected based on three sinusoidal stripe patterns.

7 is a schematic block diagram of an electronic device according to an embodiment of the present application.

detailed description

The technical solutions in the embodiments of the present application will be described below with reference to the drawings.

It should be understood that the technical solutions of the embodiments of the present application can be applied to various electronic devices, such as smart phones, notebook computers, tablet computers, game devices, and other portable or mobile computing devices, as well as electronic databases, automobiles, and bank automatic teller machines , ATM) and other electronic devices, but this embodiment of the present application is not limited thereto.

As a common application scenario, the optical fingerprint system provided by the embodiments of the present application can be applied to smartphones, tablet computers, and other mobile terminals or other terminal devices with display screens; more specifically, in the above terminal devices, fingerprint recognition The device may specifically be an optical fingerprint recognition device, which may be disposed in a partial area or all areas below the display screen, thereby forming an under-display (Under-display or Under-screen) optical fingerprint system.

It should also be understood that, in addition to fingerprint recognition, the technical solutions of the embodiments of the present application may also perform other fingerprint recognition based on the principle of optical imaging, for example, face recognition, etc. This embodiment of the present application is not limited thereto.

1 and 2 show a schematic diagram of an electronic device 100 to which the fingerprint identification device according to an embodiment of the present application can be applied, wherein FIG. 1 is a schematic front view of the electronic device 100, and FIG. 2 is AA 'partial cross-sectional structure diagram.

As shown in FIG. 1 and FIG. 2, the electronic device 100 includes a display screen 120 and an optical fingerprint recognition device (hereinafter also simply referred to as a fingerprint recognition device) 130, wherein the optical fingerprint recognition device 130 has one or more sensors An array, the sensing array is at least disposed in a partial area below the display screen 120, so that the fingerprint collection area (or sensing area) 103 of the optical fingerprint recognition device 130 is at least partially located in the display area 102 of the display screen 120 .

It should be understood that the area of the fingerprint detection area 103 may be different from the area of the sensing array of the optical fingerprint recognition device 130, for example, through optical path design such as lens imaging, reflective folding optical path design, or other optical path design such as light gathering or reflection , The area of the fingerprint detection area 103 of the optical fingerprint identification device 130 can be larger than the area of the sensing array of the optical fingerprint identification device 130. In other alternative implementations, if the light path is guided by, for example, light collimation, the fingerprint detection area 103 of the optical fingerprint identification device 130 may also be designed to be consistent with the area of the sensing array of the optical fingerprint identification device 130.

As shown in FIG. 1, the fingerprint detection area 103 is located in the display area 102 of the display screen 120. Therefore, when the user needs to unlock the electronic device or other fingerprint verification, he only needs to press his finger Fingerprint input can be realized in the fingerprint detection area 103 located on the display screen 120. Since fingerprint detection can be implemented within the screen, the electronic device 100 adopting the above structure does not require a special reserved space on the front to set fingerprint keys (such as the Home key), so that a full screen solution can be adopted, that is, the display area of the display screen 120 102 can be basically extended to the front of the entire electronic device 100.

As an embodiment, the display screen 120 may be a self-luminous display screen, which uses a self-luminous display unit as a display pixel, such as an organic light-emitting diode (Organic Light-Emitting Diode, OLED) display screen or a micro light-emitting diode (Micro- LED) display. Taking an OLED display screen as an example, the optical fingerprint recognition device 130 may use the OLED display unit (ie, OLED light source) of the OLED display screen 120 located in the fingerprint recognition area 103 as an excitation light source for optical fingerprint detection.

In other embodiments, the optical fingerprint recognition device 130 may also use an internal light source or an external light source to provide an optical signal for fingerprint detection. In this case, the optical fingerprint recognition device 130 may be applied to a non-self-luminous display, such as a liquid crystal display (Liquid Crystal Display, LCD) or other passive light-emitting display. Taking an LCD screen with a backlight module and a liquid crystal panel as an example, in order to support under-screen fingerprint detection of the LCD screen, the optical fingerprint system of the electronic device 100 may further include an excitation light source for optical fingerprint detection. The excitation light source may specifically be an infrared light source or a light source of a non-visible light of a specific wavelength, which may be provided under the backlight module of the liquid crystal display screen or the edge area under the protective cover of the electronic device 100, and the The optical fingerprint recognition device 130 may be disposed under the edge area of the liquid crystal panel or the protective cover and guided by the optical path so that the fingerprint detection light can reach the optical fingerprint recognition device 130; or, the optical fingerprint recognition device 130 may also be disposed at the Under the backlight module, and the backlight module allows the fingerprint detection light to pass through the liquid crystal panel and the backlight module and reach the optics through openings or other optical design of the film layers such as the diffusion sheet, the brightness enhancement sheet, the reflection sheet, etc. Fingerprint recognition device 130.

In addition, the sensing array of the optical fingerprint recognition device 130 is specifically a photodetector (Photodetector) array, which includes a plurality of photodetectors distributed in an array, and the photodetectors can be used as the optical sensing unit as described above. When a finger touches, presses, or approaches (for ease of description, this application is collectively referred to as touch) on the fingerprint recognition area 103, the light emitted by the display unit of the fingerprint recognition area 103 reflects on the fingerprint on the surface of the finger and forms reflected light The reflected light of the ridges and valleys of the finger fingerprint is different. The reflected light is received from the display screen 120 and received by the photodetector array and converted into a corresponding electrical signal, that is, a fingerprint detection signal. Based on the fingerprint detection signal, fingerprint image data can be obtained, and fingerprint matching verification can be further performed, thereby implementing an optical fingerprint recognition function in the electronic device 100.

It should be understood that, in a specific implementation, the electronic device 100 further includes a transparent protective cover 110, and the cover 110 may be specifically a transparent cover, such as a glass cover or a sapphire cover, which is located on the display screen 120 above and covering the front of the electronic device 100. Therefore, in the embodiment of the present application, the so-called finger touch, pressing or approaching on the display screen 120 actually refers to the finger touching, pressing or approaching the cover plate 110 above the display screen 120 or covering the cover plate 110 Surface of the protective layer. In addition, the electronic device 100 may further include a touch sensor, and the touch sensor may be specifically a touch panel, which may be provided on the surface of the display screen 120, or may be partially or wholly integrated into the display screen 120, namely The display screen 120 is specifically a touch display screen.

As an optional implementation manner, as shown in FIG. 2, the optical fingerprint recognition device 130 includes an optical detection unit 134 and an optical component 132, and the optical detection unit 134 includes the sensing array and the sensor array. The reading circuit and other auxiliary circuits that are sexually connected can be fabricated on a chip (Die) through a semiconductor process; that is, the optical detection unit 134 can be fabricated on an optical imaging chip or an image sensor chip (hereinafter also referred to as an optical fingerprint) Sensor or optical fingerprint sensor chip). The optical component 132 may be disposed above the sensing array of the optical detection unit 134, which may specifically include an optical filter (or filter, filter), an optical path guiding structure, and other optical elements. The filter can be used to filter out the ambient light penetrating the finger, and the light path guiding structure is mainly used to guide the light path such as collimating, modulating or converging the downward propagating light to realize the reflection from the finger surface The light is guided to the sensing array for optical detection.

In a specific implementation, the optical component 132 may be packaged with the optical detection unit 134 in the same optical fingerprint chip, or the optical component 132 may be disposed outside the chip where the optical detection unit 134 is located, such as The optical component 132 is attached to the chip, or a part of the components of the optical component 132 is integrated into the chip. Among them, the optical path guiding structure of the optical component 132 has various implementation solutions, for example, it may be specifically an optical path modulator or an optical path collimator made of semiconductor silicon wafers or other substrates, which has multiple optical path modulation units or A collimating unit, the optical path modulation unit or the collimating unit may be specifically a micro-hole array. Alternatively, the light guide layer may also be an optical lens (Lens) layer, which has one or more lens units, such as a lens group composed of one or more aspheric lenses (hereinafter also referred to as a lens group). After the reflected light reflected from the finger is collimated or condensed by the micro-hole array or the lens unit, and received by the optical sensing unit below it, the sensing array can detect the fingerprint image of the finger .

A circuit board 140, such as a flexible printed circuit (FPC), may also be provided under the optical fingerprint recognition device 130, and the optical fingerprint recognition device 130 may be soldered to the circuit board 140 through pads, for example. In addition, the circuit board 140 realizes electrical interconnection and signal transmission with other peripheral circuits or other elements of the electronic device 100. For example, the optical fingerprint recognition device 130 may receive the control signal of the processing unit of the electronic device 100 through the circuit board 140, and may also output the fingerprint detection signal to the electronic device through the circuit board 140 100 processing unit or control unit.

The specific identification process of traditional fingerprint identification may be: using visible light of a certain wavelength as a light source for illuminating the fingerprint, specifically, the light source may illuminate the fingerprint detection area on the display screen, thereby forming a solid color spot, such as a green spot, in the fingerprint detection area That is, all display pixels in the fingerprint detection area are all lit. When a finger touches, presses, or approaches (for ease of description, collectively referred to as pressing in this application) the fingerprint detection area, the optical signal emitted by the light source is reflected by the finger in contact with the fingerprint detection area to form an optical signal containing fingerprint information. The sensor receives the reflected light and uses the principle of light reflection imaging to perform fingerprint identification.

Generally speaking, fingerprint molds made of artificial materials, such as those made of milky white rubber, transparent rubber, black rubber or flesh-colored rubber, have obvious differences in structure and material from real fingers. Specifically, the fingerprint mold is usually made by the process of inverted mold, so the structure and material of the surface and the inside are all the same type and uniform, and the structure of the real finger is composed of different layers, including the epidermis layer, the dermis layer, and the flesh tissue And phalanx. The optical signal is irradiated on the real and fake fingers, and further imaged on the optical fingerprint module. The optical signal received by the optical fingerprint module mainly includes two parts. The first part is the light signal reflected from the surface of the finger, and the second part is from the inside of the finger. That is to say, due to the difference in the structure and material of the real and fake fingers, the scattered light signals have obvious differences. Based on this, an embodiment of the present application proposes a fingerprint recognition scheme, by forming a non-pure color spot, that is, a spot with a difference between light and dark, in the fingerprint detection area, based on the non-pure color spot, a fingerprint image is collected, and further a finger is obtained based on the fingerprint image The light signal reflected from the surface and the light signal scattered from the inside of the finger can determine the true and fake fingerprints based on the difference between the two signals.

The fingerprint recognition device of the embodiment of the present application will be described in detail below with reference to FIGS. 3 and 4.

FIG. 3 shows a schematic diagram of a fingerprint identification device according to an embodiment of the present application. As shown in FIG. 3, the fingerprint recognition device 300 includes an optical fingerprint sensor 320 for collecting at least one object to be recognized when the object to be recognized presses at least one predetermined pattern sequentially displayed on the fingerprint detection area of the display screen A fingerprint image, wherein each fingerprint image corresponds to a predetermined pattern, and the intensity of the optical signal corresponding to the first area 312 in the predetermined pattern is greater than the intensity of the optical signal corresponding to the second area 313 in the predetermined pattern.

That is to say, the first area 312 in the predetermined pattern is a bright light area, and the second area 313 in the predetermined pattern is a dark light area, that is, the predetermined pattern is a pattern having a light-dark difference.

It should be noted that, if the at least one pattern includes a plurality of predetermined patterns, the bright light area and the dark light area of each predetermined pattern are different, assuming that the plurality of predetermined patterns include a first predetermined pattern and a second predetermined pattern, in one possibility In the case of, the bright area of the first predetermined pattern corresponds to the dark area of the second predetermined pattern.

Optionally, in the embodiment of the present application, the fingerprint identification device 300 may further include:

The optical component 330 is used for guiding or condensing the fingerprint detection signal to the optical fingerprint sensor 320, wherein the fingerprint detection signal is an optical signal corresponding to a predetermined pattern formed in the fingerprint detection area of the display screen on the surface of the object to be recognized Reflected and internally scattered light signals.

It should be understood that the optical component 330 may correspond to the optical component 132 in the embodiment shown in FIG. 1. For specific implementation, reference may be made to the related description of the foregoing embodiment, and details are not described herein again.

It should also be understood that in the embodiment of the present application, the fingerprint identification device 300 may be a fingerprint identification module, corresponding to the optical fingerprint identification device 130 in FIG. 1, or the fingerprint identification device 300 may also be a fingerprint identification module Electronic equipment, which is not limited in the embodiments of the present application.

Optionally, in an embodiment of the present application, the at least one predetermined pattern is formed by an optical signal emitted by a light source in the fingerprint detection area, wherein the light source includes at least one of a red light source, a green light source, and a blue light source .

Optionally, as an embodiment, the light source is a partial self-luminous display unit 311 of the display screen in the fingerprint detection area, then the red light source, the green light source, and the blue light source are respectively The red display unit, green display unit and blue display unit of the display screen are described.

Optionally, in other embodiments, the light source may also be an internal light source or an external light source of the fingerprint identification module, which is not limited in the embodiments of the present application.

In a specific implementation, the intensity of the light signal emitted by the light source to the bright light area in the predetermined pattern may be controlled to be greater than the intensity of the light signal emitted to the dark light area to form each predetermined pattern.

For example, the at least one predetermined pattern includes a first predetermined pattern, a first area of the first predetermined pattern is a bright light area and a second area of the first pattern is a dark light area, then the fingerprint detection area of the display screen displays the The first predetermined pattern may be to turn on the self-luminous display unit in the first area of the fingerprint detection area and turn off the self-luminous display unit in the second area of the fingerprint detection area, thereby forming the first predetermined pattern.

Optionally, in the embodiment of the present application, the at least one predetermined pattern may include a plurality of predetermined patterns, and the plurality of predetermined patterns may be light and dark complementary patterns, that is, the superimposed pattern of the plurality of patterns may be a single color Pattern, that is, a solid color spot, for example, a white spot, a cyan spot, or a green spot.

Optionally, in the embodiment of the present application, the plurality of predetermined patterns may be obtained by phase shifting of the same pattern, for example, the plurality of predetermined patterns include a first pattern and a second pattern, and the first pattern is a pattern with a difference in light and dark , The second pattern may be obtained by shifting the first pattern by π, or the plurality of patterns may also include more patterns, for example, the first pattern, the second pattern, and the third pattern, the second pattern and The third pattern may be obtained by phase shifting the first pattern by 2π / 3 and 4π / 3 respectively, as long as the superimposed pattern of the plurality of predetermined patterns can be a solid color spot. The phase interval is not specifically limited.

Hereinafter, with reference to FIG. 4, a possible implementation manner of the predetermined pattern will be described.

For example, as shown in FIG. 4, the plurality of predetermined patterns may be a plurality of stripe patterns with light and dark intervals, and the period of the light and dark intervals in the stripe pattern may be one or more pixels, for example, n pixels may be used as bright, For a stripe pattern with m pixels dark, multiple stripe patterns are obtained by phase shifting, for example, 3 stripe patterns, and the phase difference between each two stripe patterns is 2π / 3.

For another example, the plurality of predetermined patterns may also be a checkerboard pattern with light and dark intervals. The period of the light and dark intervals in the checkerboard pattern may be one or more pixels. For example, n pixels may be bright and m pixels may be dark In the checkerboard pattern, multiple checkerboard patterns are obtained by phase shifting, for example, 3 checkerboard patterns, and the phase difference between each two checkerboard patterns is 2π / 3.

Optionally, the n and m may be the same or different, which is not limited in the embodiment of the present application, for example, n and m may be any integer from 5 to 10.

It should be understood that the plurality of predetermined patterns in the embodiment of the present application may also be other regular patterns, such as the ring pattern shown in FIG. 4, or may also be irregular patterns, and only the superimposed patterns of the plurality of predetermined patterns are solid colors The light spot may be sufficient, which is not limited in the embodiments of the present application.

In the embodiment of the present application, when the object to be recognized presses the fingerprint detection area of the display screen, and the fingerprint detection area of the display screen may sequentially display the at least one predetermined pattern, the optical fingerprint sensor 320 may sequentially collect data for the at least one At least one fingerprint image of the predetermined pattern, since the predetermined pattern is a light spot with light and dark differences, the collected fingerprint image is also an image with light and dark differences. For the bright light area of the fingerprint pattern, it usually includes the image formed by the two parts of the optical signal described above, while for the dark light area of the fingerprint pattern, it usually includes only the image formed by the second part of the optical signal. Therefore, by processing the collected at least one fingerprint image with light and dark differences, the images formed by the two parts of the optical signal can be determined and recorded as the first target image and the second target image. Further, according to the first The target image and the second target image determine the true and false fingerprints.

It should be noted that, in the embodiment of the present application, the first target image may be understood as an image formed by the optical signal reflected by the optical signal corresponding to the predetermined pattern on the surface of the object to be identified when the predetermined pattern is a solid color spot, the The second target image can be understood as an image formed by the light signal scattered inside the object to be identified when the predetermined pattern is a solid color spot.

Because for different materials, the first target image and the second target image have obvious differences, for example, for a fingerprint mold, the difference between the first target image and the second target image is relatively higher than that of a real finger Therefore, in an alternative embodiment, the difference between the first target image and the second target image can be compared to determine the true and false fingerprints. For example, the difference between the first target image and the second target image can be less than It is determined to be a fake fingerprint when it is a specific threshold, and it is determined to be a real fingerprint when the difference between the first target image and the second target image is greater than a specific threshold.

In other optional embodiments, a large number of fingerprint images of real fingers can be trained to obtain the first target image model and the second target image model corresponding to the real fingers, and then the subsequent fingerprint images of the object to be identified During false recognition, the first target image of the object to be recognized can be compared with the first target image model, and / or the second target image of the object to be recognized can be compared with the second target image model. When the image matches the first target image model, and / or the second target image matches the second target image model, it is determined to be a real fingerprint, otherwise it is determined to be a fake fingerprint.

It should be understood that the matching between the first target image and the first target image model may include that the difference between the values of corresponding pixels in the first target image and the first target image model is less than a certain threshold, or the first target image and the first target The proportion of the number of pixel points where the difference between the corresponding pixel points in the image model is less than a specific threshold is greater than a specific ratio, such as 95%. A similar determination method can also be adopted for the second target image and the second target image model matching, which will not be repeated here.

Optionally, in some embodiments, the fingerprint identification device 300 may further include:

The processor is configured to determine the first target image and / or the second target image according to the plurality of fingerprint images corresponding to the plurality of predetermined patterns and the phase relationship between the plurality of predetermined patterns, further according to the The first target image and / or the second target image determine whether the object to be recognized is a real finger.

As can be seen from the above description, the plurality of predetermined patterns can be obtained by phase shifting the same pattern, then the plurality of fingerprint images obtained from the plurality of predetermined patterns also have corresponding phase relationships. Therefore, according to the The two parts of the optical signal also have corresponding phase relationships. Therefore, according to the multiple fingerprint images combined with the phase relationship, the image signals corresponding to the two parts of the optical signal can be obtained respectively. The specific implementation process is combined with the specific embodiment in the method embodiment. Elaboration, no more details here.

It should be understood that the processor may be a processor of an electronic device, for example, the host module may also be a processor in a fingerprint identification module, for example, a micro control unit (Micro Control Unit, MCU), which is implemented in this application Examples are not limited to this.

Optionally, in some specific embodiments, the processor is specifically used to:

According to the first target image and the second target image and the reference fingerprint image, a first ratio and a second ratio are determined, and whether the object to be recognized is a real finger is determined according to the determined first ratio and the second ratio.

Optionally, in the embodiment of the present application, the reference fingerprint image is a fingerprint image collected based on a solid color spot. Specifically, a solid color spot may be displayed in a fingerprint detection area, and a fingerprint image is collected based on the solid color spot. The fingerprint image may be used as the Reference fingerprint image; or, because the superimposed pattern of the plurality of predetermined patterns in the embodiment of the present application is a solid color spot, the reference fingerprint image may also be a superimposed image of multiple fingerprint images corresponding to the plurality of predetermined patterns. Optionally, as an embodiment, the processor may determine the first average value of the sampling values of each pixel in the reference fingerprint image, and the second of the sampling values of all pixels in the first target image The ratio of the average value to the first average value is determined as the first ratio, and the ratio of the third average value of the sampling values of all the pixels in the second target to the first average value is determined as the second ratio. It is further determined whether the first ratio falls within the first preset range and whether the second ratio falls within the second preset range to determine whether the object to be recognized is a real finger. For example, the processor may determine that the object to be measured is a real finger when the first ratio is within the first preset range and the second ratio is within the second preset range, otherwise, determine that the object to be measured is a fake finger . Alternatively, the processor may determine that the object to be measured is a real finger when the first ratio is within the first preset range or the second ratio is within the second preset range.

Table 1 is a comparison of the first ratio L _d _Nomal, the second ratio L _g _Nomal and the ratio of the second ratio and the first ratio L _{g_Normal} / L _{d_Normal} determined by the fingerprint mold made of two artificial materials and the fingerprint image of the real finger table.

Table 1

指纹图像Fingerprint image	L _d_Nomal L _d _Nomal	L _g_Nomal L _g _Nomal	L _{g_Normal}/L _{d_Normal} L _{g_Normal} / L _{d_Normal}
真实手指的指纹图像Fingerprint image of real finger	0.5510.551	-0.332-0.332	-0.602-0.602
乳白橡胶假指纹图像Milky white rubber fake fingerprint image	0.4620.462	-0.170-0.170	-0.369-0.369
透明橡胶假指纹图像Transparent rubber fake fingerprint image	0.4190.419	-0.092-0.092	-0.219-0.219

As can be seen from the above description, since the artificial material has the characteristics of uniform and isotropic material, the difference between the light signal reflected from the surface of the fingerprint mold of the artificial material and the light signal scattered from the inside of the fingerprint mold is small, and the real finger includes multiple Different structures, so the difference between the light signal reflected from the surface of the finger and the light signal scattered from the inside of the finger is large. This is also demonstrated from Table 1, that is, the difference between L _d _Nomal and L _g _Nomal for real fingers is greater than The difference between L _d _Nomal and L _g _Nomal of the fingerprint mold made of artificial materials, therefore, the true and false fingerprints can be determined according to parameters such as the difference between the first ratio and the second ratio or the ratio between the first ratio and the second ratio.

It should be understood that in the embodiment of the present application, the pixels or pixel units in the fingerprint detection area may refer to the self-luminous display unit or light-emitting pixels of the display screen, and the pixel points in the fingerprint image may correspond to the sensing unit in the optical fingerprint sensor. The sampling value of the pixels in the image is the size of the light signal collected by the sensing unit in the optical fingerprint sensor.

Optionally, in other optional embodiments, the processor may also determine a first scale image based on the first target image and the reference fingerprint image, specifically, the first target image and the reference fingerprint image may be The ratio of the sample values of the corresponding pixels is determined as the sample values of the corresponding pixels in the first scale image, and then the average value of the sample values of all pixels in the first scale image can be determined as the first scale; similar Alternatively, the second scale image may be determined according to the second target image and the reference fingerprint image, and the average value of the sample values of corresponding pixels in the second scale image may be used as the second scale.

Above, the manner of determining the first ratio and the second ratio based on the first target image and the second target image, and referring to the fingerprint image are only examples, and other similar equivalent deformations also fall within the protection scope of the embodiments of the present application. This embodiment of the present application does not limit this.

Optionally, the processor may also directly determine whether the object to be recognized is a real finger based on the first scale image or the second scale image, for example, the processor may determine the first scale image and the first scale image model Whether it matches, or whether the second scale image and the second scale image model match, it is determined if the first scale image and the first scale image model match or the second scale image and the second scale image model match The object to be recognized is a real finger, otherwise, it is determined that the object to be recognized is a fake finger.

Here, for the determination method of the first scale image model and the second scale image model, reference may be made to the determination methods of the first target image model and the second target image model in the foregoing embodiments, and for the sake of brevity, no further description is provided here.

Optionally, in the embodiment of the present application, the first preset range may be determined according to the sampling values of all pixels of the first target image corresponding to the fingerprint image of a large number of real fingers and the reference fingerprint image, or may also be based on the foregoing The first target image model and the reference fingerprint image determine the first preset range, for example, the range where the ratio of the values of the corresponding pixel points in the first target image model and the reference fingerprint image can be determined as the The first preset range, or the range in which the ratio between the average value of the sampling value of each pixel in the first target image model and the first average value may be determined as the first preset range. The second preset range may be determined in a similar manner, and for the sake of brevity, details are not described here.

The device embodiments of the present application are described in detail above with reference to FIGS. 3 to 4, and the method embodiments of the present application are described in detail below with reference to FIGS. 5 and 6. It should be understood that the method embodiments and the device embodiments correspond to each other and are similar The description can refer to the device embodiment.

FIG. 5 shows a schematic flowchart of a fingerprint identification method according to an embodiment of the present application. The fingerprint identification method shown in FIG. 5 may be executed by the fingerprint identification device in the foregoing embodiment.

As shown in FIG. 5, the fingerprint identification method 500 may include the following steps:

S510, when the object to be recognized presses at least one predetermined pattern sequentially displayed on the fingerprint detection area of the display screen, at least one fingerprint image of the object to be recognized is collected, wherein each fingerprint image corresponds to a predetermined pattern, and among the predetermined patterns The intensity of the optical signal corresponding to the first area is greater than the intensity of the optical signal corresponding to the second area in the predetermined pattern.

S520: Determine a first target image and / or a second target image according to the at least one fingerprint image, where the first target image includes the optical signal reflected by the optical signal corresponding to the at least one predetermined pattern on the surface of the object to be identified The second target image includes an image formed by optical signals scattered by the optical signal corresponding to the at least one predetermined pattern inside the object to be identified.

S530: Determine whether the object to be recognized is a real finger according to the first target image and / or the second target image.

Optionally, in some embodiments, the at least one predetermined pattern includes a plurality of predetermined patterns, and when the object to be recognized presses at least one predetermined pattern on the fingerprint detection area of the display screen, at least one of the objects to be recognized is collected Fingerprint images, including:

Each predetermined pattern of the plurality of predetermined patterns is sequentially displayed in the fingerprint detection area of the display screen, and based on each predetermined pattern, a corresponding fingerprint image is collected.

Optionally, in some embodiments, the plurality of predetermined patterns are obtained by phase shifting the same pattern, and the superimposed pattern of the plurality of predetermined patterns is a single color pattern.

Optionally, in some embodiments, the plurality of predetermined patterns include a first predetermined pattern and a second predetermined pattern, and the fingerprint detection area of the display screen sequentially displays each of the predetermined patterns Patterns, including:

Controlling to turn on the optical signal of only the area where the fingerprint ridge pattern in the target fingerprint image is located to display the first predetermined pattern; or

Controlling to only turn on the optical signal of the area where the fingerprint valley pattern in the target fingerprint image is located to form the second predetermined pattern;

Wherein, the target fingerprint image is a fingerprint image collected based on a predetermined pattern of a single color.

Optionally, the plurality of predetermined patterns are a plurality of striped patterns or a plurality of checkerboard patterns.

Optionally, in some embodiments, the determining the first target image and / or the second target image based on the at least one fingerprint image includes:

The first target image and / or the second target image are determined according to the multiple fingerprint images corresponding to the multiple fringe images and the phase relationship of the multiple fringe images.

Extracting the fingerprint information of the bright area and the fingerprint information of the dark area of each fingerprint image in the plurality of fingerprint images, wherein the bright area of each fingerprint image is the first of a predetermined pattern corresponding to the fingerprint image An imaging area of the optical signal reflected by the area, the dark light area of each fingerprint image is an imaging area of the optical signal reflected by the second area of the predetermined pattern corresponding to each fingerprint image;

Optionally, the determining whether the object to be recognized is a real finger based on the first target image and / or the second target image includes:

Determine the first scale and / or the second scale based on the first target image and / or the second target image and the reference fingerprint image, where the reference fingerprint image corresponds to a predetermined pattern of a single color;

According to the first ratio and / or the second ratio, it is determined whether the object to be recognized is a real finger.

Optionally, the determining the first ratio and / or the second ratio based on the first target image and / or the second target image and the reference fingerprint image includes:

Determine the first average value of the sampling value of each pixel in the reference fingerprint image;

Determining the ratio of the second average value of the sampling values of all pixels in the first target image to the first average value as the first ratio; and / or sampling all the pixels in the second target image The ratio of the third average of the values to the first average is determined as the second ratio.

Optionally, the determining whether the object to be recognized is a real finger according to the first ratio and / or the second ratio includes:

If the first ratio is within the first preset range and / or the second ratio is within the second preset range, it is determined that the object to be recognized is a real finger.

Optionally, the at least one predetermined pattern is formed by an optical signal emitted by a light source in the fingerprint detection area, where the light source includes at least one of a red light source, a green light source, and a blue light source.

Optionally, the light source is a partial self-luminous display unit of the display screen in the fingerprint detection area, and the red light source, the green light source and the blue light source are the red display unit, the green display unit and the blue light source of the display screen, respectively Color display unit.

Optionally, in some embodiments, the method 500 may further include:

Controlling to turn on the self-luminous display unit in the first area of the fingerprint detection area and turning off the self-luminous display unit in the second area to form each predetermined pattern.

Optionally, the wavelength of the corresponding optical signal of the pattern in the first area is the center wavelength of the optical fingerprint sensor used for fingerprint collection.

Preferably, the wavelength of the optical signal corresponding to the pattern in the first area may be the center wavelength most sensitive to imaging by the optical fingerprint sensor, such as green light, but the embodiment of the present application does not limit this.

The fingerprint identification method according to the embodiment of the present application will be described in detail below with reference to specific embodiments.

Embodiment 1: The plurality of predetermined patterns are three sinusoidal stripe patterns with a phase interval of 2π / 3.

Wherein, the three sinusoidal stripe patterns respectively correspond to the first optical signal, the second optical signal and the third optical signal.

Alternatively, in a specific implementation, the sin (k ₁ x + k ₂ sin (y)) function can be used to generate three sinusoidal fringe patterns with light and dark intervals, where k ₁ and k ₂ can be used to control the The interval between light and dark areas in a sinusoidal stripe pattern.

Optionally, the wavelength of the optical signal corresponding to the area lit by the stripes may be set to the center wavelength of the optical fingerprint sensor, for example, the wavelength of the green band, to improve the fingerprint recognition performance.

Further, the three sinusoidal fringe patterns are sequentially displayed in the fingerprint detection area, and based on each sinusoidal fringe pattern, a fingerprint image is collected to obtain three fingerprint images L ₁ , L _2, and L ₃ , as shown in FIG. 6.

According to the function of generating the three sinusoidal fringe patterns, the expressions of the fingerprint images L ₁ , L ₂ and L ₃ can be obtained as shown in formula (1) -formula (3):

L ₁ = L _d · (0.5 + 0.5 · sin (φ)) + L _g / 2 (1)

L ₂ = L _d · (0.5 + 0.5 · sin (φ + 2π / 3)) + L _g / 2 (2)

L ₃ = L _d · (0.5 + 0.5 · sin (φ + 4π / 3)) + L _g / 2 (3)

Where L _{d is} the first target image, and L _{g is} the second target image.

It can be understood that the L _d includes the sum of fingerprint information carried in the optical signal reflected from the surface of the object to be identified when the first optical signal, the second optical signal, and the third optical signal respectively illuminate the object to be identified, or, It can also be considered that L _d is an image formed by the optical signal reflected from the surface of the object to be identified when the superimposed optical signal of the first optical signal, the second optical signal, and the third optical signal illuminates the object to be identified.

Similarly, the L _g includes the sum of fingerprint information carried in the optical signals reflected from the surface of the object to be recognized when the first optical signal, the second optical signal, and the third optical signal respectively illuminate the object to be identified, or, It can also be considered that the L _g is an image formed by the optical signals scattered from the inside of the object to be recognized when the superimposed optical signals of the first optical signal, the second optical signal, and the third optical signal illuminate the object.

It can be seen from formula (1) -formula (3) that there is a fixed phase difference between the collected fingerprint images, and the fixed phase difference may correspond to the phase interval between the three sinusoidal fringe patterns. The three fingerprint patterns are superimposed to obtain a single-color image. In some embodiments, the single-color fingerprint image can be used as the reference fingerprint image in the foregoing embodiments.

It should be understood that in formula (1) -formula (3), the coefficient of L _g can be determined according to the number of pixels occupied by bright stripes and the number of pixels occupied by dark stripes, if the pixels of bright stripes and dark stripes cycle is 8 pixels, 8 pixels brighter i.e., 8 pixels off, in this case L _g L _g is 1/2 of the full brightness of all the pixels, or when, if the bright stripes cycle is 8 pixels pixels, dark stripe pixel period is four pixels, i.e., eight pixels lit, off four pixels, in this case L _g L _g is 2/3, and so on for all pixels at full brightness, the embodiment of the present application The example only takes the same pixel period of the bright and dark stripes as an example for description. In other cases, it is only necessary to adjust the coefficients of L _g in formula (1) -formula (3), and for the sake of brevity, they are not described here.

Further, the first target image L _d and the second target image L _g can be obtained according to formula (1) -formula (3), as shown in the following formula:

L _g = 2L ₁ -L _d · (1 + sin (φ)) (5)

Among them, cos (φ) = (2L ₂ -2L ₃ ) / L _d ,

Then, it can be determined whether the object to be recognized is a fingerprint finger according to the determined first target image L _d and second target image L _g . For specific implementation, reference may be made to the related description in the foregoing embodiment.

Embodiment 2: The plurality of predetermined patterns are three checkerboard patterns with a phase interval of 2π / 3.

As mentioned above, the checkerboard pattern may be a checkerboard pattern in which n pixels are bright and m pixels are dark. The n and m may be the same or different. For example, the n may be 6 to 12, and the m may also be 6 ～ 12. Take n = 8 and m = 8 as examples, that is, the pixel period of the bright light area is 8, and the pixel fingerprint of the dark light area is also 8.

In this Embodiment 2, the fingerprint information of the bright light area and the fingerprint information of the dark light area in the fingerprint image collected based on each checkerboard pattern can be extracted.

The fingerprint information in the bright area of the fingerprint image includes fingerprint information carried by the optical signal corresponding to the predetermined pattern corresponding to the fingerprint image on the surface of the object to be recognized and the optical signal corresponding to the predetermined pattern corresponding to the fingerprint image at Fingerprint information carried by the light signal scattered inside the object to be identified.

That is, the extracted fingerprint information L _max of the bright light area and the fingerprint information L _{min of the} dark light area have the following relationship with the first target image L _d and the second target image L _g :

L _max = L _d + L _g / 2 (6)

L _g = 2L _min (7)

Similar to Embodiment 1, the coefficient of L _g can be determined according to the number of pixels occupied by bright areas and the number of pixels occupied by dark areas. The formula (6) and formula (7) are in bright light. The pixel period of the area and the dark area is determined when the pixel period is 8, so the coefficient is 1/2. In other cases, the coefficient can be adjusted accordingly, which will not be repeated here.

Further, the first target image L _d and the second target image L _g may be solved according to formula (6) and formula (7), and then the to-be-recognized may be determined according to the first target image L _d and the second target image L _g Whether the object is a real finger can be referred to the related description in the foregoing embodiment for specific implementation. In this embodiment 2, one first target image and one second target image can be determined based on each fingerprint image, that is, multiple first target images and multiple second target images can be extracted. In a specific implementation, the The extracted multiple first target images are superimposed to obtain a first target image for true and false fingerprint recognition, and the multiple second target images are superimposed to obtain a second target image for true and false fingerprint recognition.

It should be understood that each of the fingerprint images collected based on the checkerboard pattern in Embodiment 2 can extract the fingerprint information L _max in the bright light region and the fingerprint information L _{min in the} dark light region, so that the formula (6 ) And formula (7) to solve a first target image L _d and a second target image L _g , that is, the embodiment of the present application can also distinguish true and false fingerprints when the collected fingerprint image is a single bright and dark fingerprint image .

Embodiment 3: The plurality of predetermined patterns include a first predetermined pattern and a second predetermined pattern, the first predetermined pattern and the second predetermined pattern are complementary patterns, wherein the first predetermined pattern is a fingerprint ridge pattern bright, fingerprint valley In the pattern where the pattern is off, the second predetermined pattern is a pattern where the fingerprint ridge pattern is off and the fingerprint valley pattern is bright.

Specifically, first obtain a fingerprint image based on a solid color spot, specifically, control all pixels in the fingerprint detection area to display a solid color spot in the fingerprint detection area, and collect a fingerprint image of an object to be recognized based on the solid color spot; then, in the The fingerprint image is displayed in the fingerprint detection area, wherein the pixels in the area where the fingerprint ridge image in the fingerprint image is located are turned on, the pixels in the area where the fingerprint valley image in the fingerprint image is located are turned off, and the first predetermined pattern is displayed based on the The first predetermined pattern collects the first fingerprint image, and then the pixels in the area where the fingerprint ridge image in the fingerprint image is located are turned off, the pixels in the area of the fingerprint valley image in the fingerprint image are turned on, and the second predetermined pattern is displayed, The second fingerprint image is collected based on the second predetermined pattern, and the first target image and the second target image may be further determined according to the first fingerprint image and the second fingerprint image. Repeat again.

Optionally, in the embodiment of the present application, before the fingerprint collection is performed, the sampling value of each pixel in the optical fingerprint sensor may also be calibrated to reduce the error of subsequent fingerprint collection.

Specifically, a shielding member may be provided above the fingerprint identification device, for example, a shielding member made of black rubber, to prevent interference of fingerprint image collection with external ambient light.

Then, the light source is controlled to emit light signals of different intensities to the fingerprint detection area, for example, 100%, 70%, and 40%. Based on these light signals of different intensities, multiple fingerprint images are collected, and further according to the multiple fingerprint images, the The sampling value of each photosensitive unit in the optical fingerprint sensor is calibrated (for example, KB calibration) to obtain the calibration value of each photosensitive unit (for example, K and B), and the calibration value can be used for Calibrate the sampled value of the photosensitive unit to reduce the measurement error caused by the hardware difference of the optical fingerprint sensor.

An embodiment of the present application also provides an electronic device 800. As shown in FIG. 7, the electronic device 800 may include a display screen 820 and the above-mentioned fingerprint recognition device 810. The fingerprint recognition device 810 may be the fingerprint recognition in the foregoing embodiment The device 300 is provided below the display screen 820. As an optional embodiment, the display screen 820 has a self-luminous display unit, and the self-luminous display unit can be used as an excitation light source for fingerprint detection by the fingerprint identification device 810. In addition, the fingerprint identification device 810 may be used to execute the content in the method embodiment shown in FIG. 5.

It should be understood that the specific examples in the embodiments of the present application are only to help those skilled in the art to better understand the embodiments of the present application, and do not limit the scope of the embodiments of the present application.

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

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

In the several embodiments provided in this application, it should be understood that the disclosed system and device may be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a division of logical functions. In actual implementation, there may be other divisions, for example, multiple units or components may be combined or Can be integrated into another system, or some features can be ignored, or not implemented. In addition, the displayed or discussed mutual couplings or direct couplings or communication connections may be indirect couplings or communication connections through some interfaces, devices, or units, and may also be electrical, mechanical, or other forms of connection.

The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or may be distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the objectives of the solutions of the embodiments of the present application.

In addition, the functional units in the embodiments of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The above integrated unit may be implemented in the form of hardware or software functional unit.

If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it may be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application essentially or part of the contribution to the existing technology, or all or part of the technical solution can be embodied in the form of a software product, the computer software product is stored in a storage medium In it, several instructions are included to enable a computer device (which may be a personal computer, server, or network device, etc.) to perform all or part of the steps of the methods described in the embodiments of the present application. The aforementioned storage media include: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), magnetic disk or optical disk and other media that can store program code .

The above is only the specific implementation of this application, but the scope of protection of this application is not limited to this, any person skilled in the art can easily think of various equivalents within the technical scope disclosed in this application Modifications or replacements, these modifications or replacements should be covered within the scope of protection of this application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

A fingerprint identification method, characterized in that it includes:

When the object to be recognized presses at least one predetermined pattern sequentially displayed on the fingerprint detection area of the display screen, at least one fingerprint image of the object to be recognized is collected, wherein each fingerprint image corresponds to a predetermined pattern, and among the predetermined patterns The intensity of the optical signal corresponding to the first area is greater than the intensity of the optical signal corresponding to the second area in the predetermined pattern;

The first target image and / or the second target image are determined according to the at least one fingerprint image, wherein the first target image includes light reflected on the surface of the object to be identified by the optical signal corresponding to the at least one predetermined pattern An image formed by the signal, the second target image is an image formed by an optical signal scattered by the optical signal corresponding to the at least one predetermined pattern inside the object to be identified;

According to the first target image and / or the second target image, it is determined whether the object to be recognized is a real finger.
The method according to claim 1, wherein the at least one predetermined pattern includes a plurality of predetermined patterns, and when the object to be recognized presses the at least one predetermined pattern that is sequentially displayed on the fingerprint detection area of the display screen, the The at least one fingerprint image of the object to be identified includes:

Sequentially displaying each of the plurality of predetermined patterns in the fingerprint detection area of the display screen;

Based on each predetermined pattern, a corresponding fingerprint image is collected.
The method according to claim 2, wherein the plurality of predetermined patterns are obtained by phase shifting the same pattern, and the superimposed pattern of the plurality of predetermined patterns is a single color pattern.
The method according to claim 3, wherein the plurality of predetermined patterns are a plurality of stripe patterns or a plurality of checkerboard patterns.
The method according to claim 2 or 3, wherein the plurality of predetermined patterns include a first predetermined pattern and a second predetermined pattern, and the plurality of predetermined patterns are sequentially displayed on the fingerprint detection area of the display screen Each predetermined pattern in the pattern includes:

Controlling to turn on the optical signal of only the area where the fingerprint ridge pattern in the target fingerprint image is located to display the first predetermined pattern; or

Controlling to only turn on the optical signal of the area where the fingerprint valley pattern in the target fingerprint image is located to form the second predetermined pattern;

Wherein, the target fingerprint image is a fingerprint image collected based on a predetermined pattern of a single color.
The method according to any one of claims 3 to 5, wherein the determining the first target image and / or the second target image based on the at least one fingerprint image includes:

The first target image and / or the second target image are determined according to multiple fingerprint images corresponding to the multiple stripe images and the phase relationship of the multiple stripe images.
The method according to any one of claims 3 to 5, wherein the determining the first target image and / or the second target image based on the at least one fingerprint image includes:

Extracting the fingerprint information of the bright area and the fingerprint information of the dark area of each fingerprint image in the plurality of fingerprint images, wherein the bright area of each fingerprint image is the first of a predetermined pattern corresponding to the fingerprint image The imaging area of the light signal reflected by the area, the dark light area of each fingerprint image is the imaging area of the light signal reflected by the second area of the predetermined pattern corresponding to each fingerprint image; according to the The fingerprint information of the bright light area and the fingerprint information of the dark light area determine the first target image and / or the second target image, wherein the fingerprint information of the bright light area of the fingerprint image includes a predetermined corresponding to the fingerprint image The fingerprint information carried by the optical signal reflected by the light signal corresponding to the pattern on the surface of the object to be recognized and the fingerprint information carried by the optical signal scattered by the light signal corresponding to the predetermined pattern corresponding to the fingerprint image inside the object to be recognized .
The method according to any one of claims 1 to 7, wherein the determining whether the object to be recognized is a real finger based on the first target image and / or the second target image includes: :

Determining a first scale and / or a second scale based on the first target image and / or the second target image and a reference fingerprint image, where the reference fingerprint image corresponds to a predetermined pattern of a single color;

According to the first ratio and / or the second ratio, it is determined whether the object to be recognized is a real finger.
The method according to claim 8, wherein the determining the first ratio and / or the second ratio based on the first target image and / or the second target image and the reference fingerprint image includes:

Determine the first average value of the sample value of each pixel in the reference fingerprint image;

Determining the ratio of the second average value of the sampling values of all pixels in the first target image to the first average value as the first ratio; and / or determining all the values in the second target image The ratio of the third average value of the sample values of the pixel points to the first average value is determined as the second ratio.
The method according to claim 9, wherein the determining whether the object to be recognized is a real finger according to the first ratio and / or the second ratio includes:

If the first ratio is within the first preset range and / or the second ratio is within the second preset range, it is determined that the object to be recognized is a real finger.
The method according to any one of claims 1 to 10, wherein the at least one predetermined pattern is formed in the fingerprint detection area by an optical signal emitted by a light source, wherein the light source includes a red light source and a green light source And at least one of the blue light sources.
The method according to claim 11, wherein the light source is a partial self-luminous display unit of the display screen in the fingerprint detection area, and the red light source, the green light source and the blue light source These are the red display unit, the green display unit and the blue display unit of the display screen.
The method of claim 12, wherein the method further comprises:

Controlling to turn on the self-luminous display unit in the first area of the fingerprint detection area and turn off the self-luminous display unit in the second area to form each of the at least one predetermined pattern.
The method according to any one of claims 1 to 13, wherein the wavelength of the corresponding optical signal of the pattern in the first area is the center wavelength of the optical fingerprint sensor used for fingerprint collection.
A fingerprint identification device, characterized in that it includes:

An optical fingerprint sensor is used to collect at least one fingerprint image of the object to be recognized when the object to be recognized presses at least one predetermined pattern sequentially displayed on the fingerprint detection area of the display screen, each fingerprint image corresponds to a predetermined pattern, wherein The intensity of the optical signal corresponding to the first area in the predetermined pattern is greater than the intensity of the optical signal corresponding to the second area in the predetermined pattern;

The at least one fingerprint image is used to determine a first target image and / or a second target image, and the first target image and / or the second target image are used to determine whether the object to be recognized is a real finger , The first target image includes the image formed by the optical signal reflected by the optical signal corresponding to the at least one predetermined pattern on the surface of the object to be recognized, and the second target image includes the light corresponding to the at least one predetermined pattern The image formed by the light signal scattered by the signal inside the object to be identified.
The device according to claim 15, wherein the at least one predetermined pattern includes a plurality of predetermined patterns, and the optical fingerprint sensor is specifically used to:

When each predetermined pattern of the plurality of predetermined patterns is sequentially displayed in the fingerprint detection area of the display screen, a corresponding fingerprint image is collected based on each predetermined pattern.
The device according to claim 16, wherein the plurality of predetermined patterns are obtained by phase shifting the same pattern, and the superimposed pattern of the plurality of predetermined patterns is a single color pattern.
The device according to claim 16 or 17, wherein the plurality of predetermined patterns are a plurality of stripe patterns or a plurality of checkerboard patterns.
The device according to claim 17, wherein the plurality of predetermined patterns include a first predetermined pattern and a second predetermined pattern, and the first area in the first predetermined pattern is a fingerprint ridge pattern in the target fingerprint image The area where the second area in the first predetermined pattern is the area where the fingerprint valley pattern in the target fingerprint image is located, and the first area in the second predetermined pattern is the fingerprint valley pattern in the target fingerprint image In the area where the second predetermined pattern is the area where the fingerprint ridge pattern in the target fingerprint image is located, the target fingerprint image is a fingerprint image collected based on a predetermined pattern of a single color.
The device according to any one of claims 17 to 19, wherein the fingerprint identification device further comprises:

The processor is configured to determine the first target image and / or the second target image according to the multiple fingerprint images corresponding to the multiple stripe images and the phase relationship between the multiple stripe images.
The apparatus according to claim 20, wherein the processor is further configured to:

Extracting the fingerprint information of the bright area and the fingerprint information of the dark area of each fingerprint image in the plurality of fingerprint images, wherein the bright area of each fingerprint image is the first of a predetermined pattern corresponding to the fingerprint image An imaging area of the optical signal reflected by the area, the dark light area of each fingerprint image is an imaging area of the optical signal reflected by the second area of the predetermined pattern corresponding to each fingerprint image;

Determining the first target image and / or the second target image according to the fingerprint information of the bright area and the fingerprint information of the dark area of each fingerprint image, wherein the fingerprint information of the bright area of the fingerprint image Including the fingerprint information carried by the optical signal corresponding to the predetermined pattern corresponding to the fingerprint image on the surface of the object to be identified and the optical signal corresponding to the predetermined pattern corresponding to the fingerprint image to be scattered inside the object to be identified The fingerprint information carried by the optical signal.
The apparatus according to any one of claims 15 to 21, wherein the processor is further configured to:

Determining a first scale and / or a second scale based on the first target image and / or the second target image and a reference fingerprint image, where the reference fingerprint image corresponds to a predetermined pattern of a single color;

According to the first ratio and / or the second ratio, it is determined whether the object to be recognized is a real finger.
The apparatus according to claim 22, wherein the processor is further configured to:

Determine the first average value of the sample value of each pixel in the reference fingerprint image;

Determining the ratio of the second average value of the sampling values of all pixels in the first target image to the first average value as the first ratio; and / or determining all the values in the second target image The ratio of the third average value of the sample values of the pixel points to the first average value is determined as the second ratio.
The apparatus according to claim 23, wherein the processor is further configured to:

If the first ratio is within the first preset range, and / or the second ratio is within the second preset range, it is determined that the object to be recognized is a real finger.
The device according to any one of claims 15 to 24, wherein the wavelength of the corresponding optical signal of the pattern in the first area is the center wavelength of the optical fingerprint sensor used for fingerprint collection.
The device according to any one of claims 15 to 25, wherein the at least one predetermined pattern is formed by an optical signal emitted by a light source in the fingerprint detection area, wherein the light source includes a red light source and a green light source And at least one of the blue light sources.
The device according to any one of claims 15 to 26, wherein the light source is a partial self-luminous display unit of the display screen in the fingerprint detection area, and the red light source and the green light source And the blue light source are a red display unit, a green display unit, and a blue display unit of the display screen, respectively.
The device according to any one of claims 15 to 27, wherein the device further comprises:

The light source driving module is used to control to turn on the self-luminous display unit in the first area of the fingerprint detection area and turn off the self-luminous display unit in the second area to form each predetermined pattern.
An electronic device, comprising: the fingerprint identification device according to any one of claims 15 to 28.