CN111274906A

CN111274906A - Fingerprint anti-counterfeiting method and device

Info

Publication number: CN111274906A
Application number: CN202010045762.9A
Authority: CN
Inventors: 程泰毅; 张骁驰; 焉逢运; 谢詹奇; 孙云刚; 杨振国
Original assignee: Silead Inc
Current assignee: Silead Inc
Priority date: 2020-01-16
Filing date: 2020-01-16
Publication date: 2020-06-12
Also published as: CN113139414A

Abstract

The invention discloses a fingerprint anti-counterfeiting method and a device, wherein the method comprises the following steps: forming an anti-counterfeiting detection light spot with a preset pattern, and illuminating a target object by using the anti-counterfeiting detection light spot, wherein the anti-counterfeiting detection light spot comprises a light-emitting area and a non-light-emitting area, and at least part of detection light emitted by the light-emitting area is reflected by the target object; receiving light which is reflected by the target object and passes through the anti-counterfeiting detection light spot to form an anti-counterfeiting image, wherein the anti-counterfeiting image comprises at least one first fingerprint feature and at least one second fingerprint feature which are separated from each other, and the first fingerprint feature and the second fingerprint feature are images of fingerprint information reflected by the same light-emitting area and mapped to the light-sensing unit; and processing the information of the first fingerprint characteristic and/or the second fingerprint characteristic to distinguish the target object as a three-dimensional finger or a two-dimensional finger. The invention can accurately identify the 2D false fingerprint, thereby improving the safety of the fingerprint identification equipment.

Description

Fingerprint anti-counterfeiting method and device

Technical Field

The invention relates to the technical field of optical fingerprint identification, in particular to a fingerprint anti-counterfeiting method and a fingerprint anti-counterfeiting device.

Background

With the rapid development of communication technology, the demand of users on mobile terminals is increasing, and the requirements on the use experience of the mobile terminals are also increasing. In order to better meet the use requirements of users, fingerprint identification is widely applied to mobile terminals as a mature biometric identification technology. The core part of the mobile terminal for realizing fingerprint identification is an optical fingerprint sensor.

As shown in fig. 1, a general optical fingerprint sensor includes: a sensor pixel array, a lens, a Light shield layer, an OLED (Organic Light-Emitting Diode) screen and a transparent layer. When the fingerprint sensor is used, the front face of the OLED screen emits detection light, the detection light is reflected by a finger pressed on the screen and is converged into the sensor pixel array below the lens through the OLED screen, and the sensor pixel array can acquire an optical image representing a fingerprint after receiving the detection light. Because the intensity of the light reflected by the peaks and the troughs of the fingerprints is different, clear fingerprint texture pictures can be shot. The fingerprint texture picture is a two-dimensional gray scale picture.

However, the applicants have found that: because the fingerprint texture picture corresponding to the fingerprint signal carried by the finger reflected light is a gray scale image which can only reflect the plane contrast, the fingerprint texture picture is easy to be attacked by 2D (two-dimensional plane) false fingerprints, and the safety of the device which needs to be used for the optical fingerprint sensor is insufficient.

Disclosure of Invention

Based on the foregoing defects in the prior art, embodiments of the present invention provide a fingerprint anti-counterfeiting method and apparatus, which can accurately identify a 2D false fingerprint, thereby improving the security of a fingerprint identification device.

In order to achieve the above object, the present invention provides the following technical solutions.

A fingerprint anti-counterfeiting method, comprising:

forming an anti-counterfeiting detection light spot with a preset pattern, and illuminating a target object by using the anti-counterfeiting detection light spot, wherein the anti-counterfeiting detection light spot comprises a light-emitting area and a non-light-emitting area, and at least part of detection light emitted by the light-emitting area is reflected by the target object;

receiving light which is reflected by the target object and passes through the anti-counterfeiting detection light spot to form an anti-counterfeiting image, wherein the anti-counterfeiting image comprises at least one first fingerprint feature and at least one second fingerprint feature which are separated from each other, and the first fingerprint feature and the second fingerprint feature are images of fingerprint information reflected by the same light-emitting area and mapped to a light-sensing unit;

and processing the information of the first fingerprint characteristic and/or the second fingerprint characteristic to distinguish the target object as a three-dimensional finger or a two-dimensional finger.

In a preferred embodiment, the area of the non-light emitting region is larger than the area of the light emitting region.

In a preferred embodiment, the area ratio of the light-emitting area to the non-light-emitting area in the pattern of the anti-counterfeiting detection light spot is greater than 1:19 and less than 1: 1.

In a preferred embodiment, the anti-counterfeiting detection light spot is a stripe light spot with alternate light and shade.

In a preferred embodiment, the ratio of the width of the light stripe to the width of the dark stripe in the stripe light spot is 3: 17.

In a preferred embodiment, the anti-counterfeit detection light spot further comprises any one of the following: light and shade alternate annular stripe light spots extending from the center to the periphery; or grid light spots which are arranged in a dark and bright mode and extend along a first direction and a second direction perpendicular to the first direction; alternatively, the light-emitting region is a plurality of discontinuous light-emitting regions formed on the non-light-emitting region.

In a preferred embodiment, the fingerprint anti-counterfeiting method further comprises: and forming a fingerprint identification light spot to illuminate the target object so as to acquire fingerprint information of the target object.

In a preferred embodiment, processing the information of the first and/or second fingerprint features comprises extracting difference parameters corresponding to a two-dimensional finger and a three-dimensional finger, respectively, of the first and/or second fingerprint features.

In a preferred embodiment, the fingerprint anti-counterfeiting method further comprises: and preprocessing the anti-counterfeiting image to obtain a converted anti-counterfeiting image, and processing the information of the first fingerprint characteristic and/or the second fingerprint characteristic in the converted anti-counterfeiting image to distinguish that the target object is a three-dimensional finger or a two-dimensional finger.

A fingerprint security device, the fingerprint security device comprising: the device comprises a detection light source, a control unit, an anti-counterfeiting detection light spot, an optical function unit and a photosensitive unit; wherein,

the anti-counterfeiting detection light spot is used as the detection light source to illuminate a target object;

the control unit controls the detection light source to form the anti-counterfeiting detection light spot with a preset pattern; the light emitted to a target object by the detection light source passes through the anti-counterfeiting detection light spot when being reflected back, and the optical function unit forms an anti-counterfeiting image on the photosensitive unit;

the anti-counterfeiting image comprises at least one first fingerprint feature and at least one second fingerprint feature which are separated from each other, and the first fingerprint feature and the second fingerprint feature are both images of fingerprint information reflected by the same position area of the target object and mapped to the photosensitive unit.

In a preferred embodiment, the fingerprint anti-counterfeiting device further comprises a fingerprint identification light spot, the fingerprint identification light spot is used for collecting fingerprint information of the target object, and the pattern of the anti-counterfeiting detection light spot is different from the pattern of the fingerprint identification light spot.

In a preferred embodiment, the anti-counterfeiting detection light spot has a light-emitting area and a non-light-emitting area, and the area of the light-emitting area is smaller than that of the non-light-emitting area.

In a preferred embodiment, the anti-counterfeiting detection light spot is a stripe pattern with alternate light and dark stripes, and the area of the dark stripes is larger than that of the light stripes.

In a preferred embodiment, the ratio of the dark zone stripe area to the light zone stripe area is greater than 1:19 and less than 1: 1.

In a preferred embodiment, the detection light source is a light source of an OLED screen.

In a preferred embodiment, the optical function unit comprises an optical lens assembly.

The technical scheme of the invention has the following remarkable beneficial effects:

the embodiment of the invention provides a fingerprint anti-counterfeiting method and a device, which are characterized in that an anti-counterfeiting detection light spot with a preset pattern is used for collecting an image of a target object, and the preset pattern of the anti-counterfeiting detection light spot enables target fingerprint information illuminated by at least one light-emitting area in the anti-counterfeiting detection light spot to generate a first fingerprint characteristic and a second fingerprint characteristic which are separated; the first fingerprint feature and/or the second fingerprint feature are/is used for distinguishing the target object as a three-dimensional finger or a two-dimensional finger corresponding to the difference between the target object as a two-dimensional finger and the three-dimensional finger, so that the safety of the fingerprint identification device can be improved.

Specific embodiments of the present invention are disclosed in detail with reference to the following description and drawings, indicating the manner in which the principles of the invention may be employed. It should be understood that the embodiments of the invention are not so limited in scope. The embodiments of the invention include many variations, modifications and equivalents within the spirit and scope of the appended claims. Features that are described and/or illustrated with respect to one embodiment may be used in the same way or in a similar way in one or more other embodiments, in combination with or instead of the features of the other embodiments.

Drawings

The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way. In addition, the shapes, the proportional sizes, and the like of the respective members in the drawings are merely schematic for facilitating the understanding of the present invention, and do not specifically limit the shapes, the proportional sizes, and the like of the respective members of the present invention. Those skilled in the art, having the benefit of the teachings of this invention, may choose from the various possible shapes and proportional sizes to implement the invention as a matter of case. In the drawings:

FIG. 1 is a schematic structural diagram of an OLED panel lower module in the prior art;

FIG. 2 is a flowchart illustrating steps of a fingerprint anti-counterfeit method according to an embodiment of the present invention;

FIG. 3 is a schematic view of a first anti-counterfeit detection light spot provided in an embodiment of the present invention;

FIG. 4 is a 3D real finger formed anti-counterfeit image;

FIG. 5 is a 2D false fingerprint formed anti-counterfeit image;

FIG. 6 is a de-noising enhanced image formed by subtracting a reference from an anti-counterfeiting image formed by a 3D real finger in FIG. 4;

FIG. 7 is a denoised enhanced image formed by subtracting a reference from the anti-counterfeit image formed by the 2D pseudo fingerprint in FIG. 5;

FIG. 8 is a schematic block diagram of a fingerprint anti-counterfeiting method according to an embodiment of the present invention;

FIG. 9 is a schematic view of a second anti-counterfeit detection light spot provided in the embodiment of the present invention;

FIG. 10 is a schematic view of a third anti-counterfeit detection light spot provided in the embodiment of the present invention;

fig. 11 is a schematic view of a fourth anti-counterfeit detection light spot provided in the embodiment of the present invention;

fig. 12 is a block diagram of a fingerprint anti-counterfeiting device according to an embodiment of the invention.

Description of reference numerals:

1. a transparent layer;

2. an OLED screen; B. detecting light spots in an anti-counterfeiting manner;

3. a light-shielding layer;

4. a lens;

5. a pixel;

20. a detection light source;

30. an optical function unit;

50. a light sensing unit;

6. a control unit;

100. fingerprint chip module.

Detailed Description

In order to make those skilled in the art better understand the technical solution of the present invention, the technical solution of the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, shall fall within the scope of the present invention.

It will be understood that when an element is referred to as being "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and the like as used herein are for illustrative purposes only and do not represent the only embodiments.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

The embodiment of the invention provides a fingerprint anti-counterfeiting method and a fingerprint anti-counterfeiting device, which can accurately distinguish or judge two-dimensional fingerprints or three-dimensional fingerprints, avoid fingerprint identification or unlocking by replacing three-dimensional fingerprints with two-dimensional fingerprint information, and improve the safety of fingerprint identification.

The fingerprint anti-counterfeiting method is applied to a mobile phone communication device for example, but the application of the fingerprint identification device to other electronic devices, such as a fingerprint lock, or other electronic devices that need to be identified and unlocked by using a fingerprint, is not limited.

In common mobile phone communication equipment, a display screen of a mobile phone is an OLED screen which is used more conventionally. According to the prior art, an OLED panel is understood to be a self-luminous display device. Therefore, in the description of this embodiment, the OLED screen may be used as a detection light source for fingerprint detection. For example, an OLED pixel array in a fingerprint sensing area on an OLED screen of a mobile phone can emit light spots to illuminate a finger to collect a user fingerprint. The conventional light spot for collecting fingerprint images can be circular or in other forms, and is referred to as a fingerprint identification light spot hereinafter.

The fingerprint identification light spot may be a light spot with any preset pattern, or may be a full bright light spot, which is not limited herein. The fingerprint identification spot may comprise any one of the following: the light source has a pure color light spot with the same brightness in a preset area and a gradual light spot with gradually-increased brightness from the center to the periphery in the preset area. The size, shape, etc. of the predetermined area may be different according to the composition distribution, etc. of the hardware structure of the device. When the fingerprint identification light spot is a gradually-changed light spot which gradually brightens from the center to the periphery, the brightness distribution of the acquired fingerprint image on the plane can be uniform.

The anti-counterfeiting detection light spot can be used for distinguishing a true finger and a 2D false fingerprint, so that the fingerprint identification equipment using the fingerprint anti-counterfeiting mode has an anti-counterfeiting function. The present application is described in detail below with reference to specific figures and embodiments.

Referring to fig. 2, in an embodiment of the present application, a fingerprint anti-counterfeiting method is provided, where the fingerprint anti-counterfeiting method includes:

step S10: forming an anti-counterfeiting detection light spot with a preset pattern, and illuminating a target object by using the anti-counterfeiting detection light spot, wherein the anti-counterfeiting detection light spot comprises a light-emitting area and a non-light-emitting area, and at least part of detection light emitted by the light-emitting area is reflected by the target object;

step S12: receiving light reflected by the target object and passing through the anti-counterfeiting detection light spot to form an anti-counterfeiting image, wherein the anti-counterfeiting image comprises at least one first fingerprint feature and at least one second fingerprint feature which are separated from each other, and the first fingerprint feature and the second fingerprint feature are images of fingerprint information reflected by the same light-emitting area of the target object and mapped to the light-sensing unit;

step S14: and processing the information of the first fingerprint characteristic and/or the second fingerprint characteristic to distinguish the target object as a three-dimensional finger or a two-dimensional finger.

In this embodiment, the lighting of the anti-counterfeit detection light spot having the preset pattern may be implemented after receiving a predetermined start signal. Specifically, the predetermined start signal may be different according to different application scenarios, and the application is not limited in this respect. For example, when the fingerprint anti-counterfeiting method is applied to an electronic device with a fingerprint identification area, the starting signal can be a signal generated by the touch or press of a finger of a user.

The light spot may be illuminated upon receipt of the activation signal. Specifically, the illuminated light spots may include anti-counterfeiting detection light spots for distinguishing between three-dimensional fingers and two-dimensional fingers. Furthermore, the illuminated spots may also include fingerprint identification spots for capturing a fingerprint image. In this embodiment, the anti-counterfeit detection light spot is different from the conventional fingerprint identification light spot in that: the anti-counterfeiting detection light spot is not used for collecting fingerprint information of a target object, but is used for distinguishing whether the target object is a two-dimensional finger or a three-dimensional finger. Therefore, the anti-counterfeiting detection light spot is not used for detecting detailed fingerprint information of the target object, but is used for judging whether the target finger is a two-dimensional finger or a three-dimensional finger. In some electronic devices for fingerprint authentication, the light spots for collecting fingerprint information may include two light spots, a fingerprint identification light spot and an anti-counterfeiting detection light spot.

Wherein, the anti-counterfeiting detection light spot is a light spot with a preset pattern. Specifically, the anti-counterfeit detection light spot may include: a light-emitting region and a non-light-emitting region. The boundary area of the light-emitting area and the non-light-emitting area is the boundary area. The predetermined pattern may be formed by a light emitting region and a non-light emitting region in the light spot, and the boundary region is a boundary of the predetermined pattern. Of course, the specific shape of the predetermined pattern can be adaptively designed according to the actual application, and the application is not limited herein.

The area of a light-emitting area in the anti-counterfeiting detection light spot is smaller than that of a non-light-emitting area, so that an obvious light and shade boundary image can be ensured in the generated anti-counterfeiting image, and a first fingerprint feature and a second fingerprint feature which are separated from each other can be generated.

In this embodiment, in the anti-counterfeit detection light spot, the area ratio of the light-emitting area to the non-light-emitting area needs to be reasonably selected. In the anti-counterfeiting detection light spot embodiments of some preset patterns, if the area ratio of the two is too small, that is, the area of the light-emitting area is too small relative to the area of the non-light-emitting area, for example, the areas of the light-emitting area and the non-light-emitting area of the anti-counterfeiting detection light spot are less than 1:19, the light source is not enough; if the light-emitting area is too large relative to the area of the non-light-emitting area, the coincidence of the finger characteristic light-emitting area and the fake finger characteristic light-emitting area affects the characteristic parameters on the separated first fingerprint characteristic and/or second fingerprint characteristic, so that the two-dimensional and three-dimensional target objects are slightly different and cannot be distinguished based on the characteristic parameters. Therefore, for the embodiments of the anti-counterfeiting detection light spots of the preset patterns, the area ratio of the light-emitting area and the non-light-emitting area of the anti-counterfeiting detection light spots can be set to be greater than 1:19 and less than 1: 1.

In the embodiments provided in the present application, the shape, area, and the like of the anti-counterfeit detection light spot can be preferably set as needed. Referring to fig. 3, in some embodiments, the anti-counterfeit detection light spot B is a light spot and a dark spot. In the present embodiment, the stripe light spot between light and dark is mainly taken as an example for detailed description, and the detailed description of the embodiment can be referred to adaptively for other detection principles of the forgery prevention detection light spot, the achieved technical effects, and the like.

As shown in fig. 3, the anti-counterfeit detection light spot B may be a light and dark stripe light spot extending along the first direction, and the light and dark stripe light spot includes a light stripe and a dark stripe. The anti-counterfeiting detection light spot B of the pattern has relatively low calibration requirement on system positions compared with anti-counterfeiting detection light spots of other patterns, and the robustness is relatively good. In the anti-counterfeiting retrieval light spot with the preset pattern, the width ratio of the bright stripes to the dark stripes can be 3: 17.

In this embodiment, the anti-counterfeit detection light spot B may be a one-dimensional light spot, for example, a line-to-line light spot, as shown in fig. 3, which is beneficial to reducing the complexity of subsequent image and data processing, and is also beneficial to ensuring the accuracy and reliability of fingerprint anti-counterfeit identification. In addition, the cost for forming the anti-counterfeiting detection light spot B is relatively low. The anti-counterfeiting detection light spot B is provided with light and shade alternative stripe light spots extending along the first direction. The bright stripes and the dark stripes of the stripe light spots are parallel to each other. The width ratio of the bright stripes to the dark stripes is 3:17, so that an anti-counterfeiting image capable of remarkably identifying 2D false fingerprints (namely two-dimensional false fingers) can be formed.

In some specific electronic devices applying fingerprint identification and/or anti-counterfeiting chips, the fingerprint identification light spot and the anti-counterfeiting detection light spot B can be lightened by using the same set of detection light sources. The detection light source can be a light source provided by a self-luminous OLED screen, and can also be other detection light sources outside the screen. In the case that the fingerprint identification light spot and the anti-counterfeiting detection light spot B are lightened by using the same set of detection light source, the fingerprint identification light spot and the anti-counterfeiting detection light spot B can be lightened at different time, and the time interval is short and exceeds the range that human eyes can capture, namely, the human eyes can hardly perceive that the light spots with two different patterns are lightened.

In the electronic equipment applied to fingerprint identification and anti-counterfeiting, fingerprint images need to be acquired by utilizing fingerprint identification light spots. After the fingerprint image is collected, the collected fingerprint image can be compared with the stored fingerprint image subsequently. If the comparison is successful, whether the fingerprint is a 2D false fingerprint can be further judged.

In this embodiment, after the anti-counterfeiting detection spot B is turned on, at least a part of the detection light emitted by the light-emitting region is reflected by the target object, and is received by the photosensitive unit after passing through the anti-counterfeiting detection spot B, so as to form an anti-counterfeiting image in the sensory unit. And target fingerprint information illuminated by at least one light-emitting area in the pseudo detection light spots B generates an anti-counterfeiting image. The security image includes a first fingerprint feature and a second fingerprint feature that are separated from each other. The first fingerprint feature and the second fingerprint feature are images of fingerprint information reflected by the same light emitting area and mapped to the photosensitive unit. The first fingerprint feature and/or the second fingerprint feature may then be used to distinguish the target object as a three-dimensional finger or a two-dimensional finger, corresponding to a difference in whether the target object is a two-dimensional finger or a three-dimensional finger.

Here, it should be noted that: the fingerprint information reflected by the same light-emitting area has a one-to-one correspondence relationship with the first fingerprint characteristic and the second fingerprint characteristic which are separated from the anti-counterfeiting image. That is, the fingerprint information reflected by the same light emitting area can be reflected by the separated first and second fingerprint features.

In one embodiment, the fingerprint identification spot or the anti-counterfeiting detection spot B can be illuminated by an OLED screen. The OLED panel includes a glass layer having opposing first and second surfaces. The first surface is at a distance H from the second surface. The first surface is provided with a detection area for contacting with a finger of a user. The detection area may be a local area on the OLED panel, or may be the entire OLED panel.

In this embodiment, a preset pattern of the false-detection-preventing light spots is exemplified by a stripe pattern between light and dark shown in fig. 3.

In the anti-counterfeiting images shown in fig. 4 and 5, a target object illuminated by the same bright stripe region generates a first fingerprint feature and a second fingerprint feature which are separated from each other in fig. 4 and 5, for example, a stripe ① is the second fingerprint feature and a stripe ② is the first fingerprint feature, a stripe ① is the second fingerprint feature and a stripe ② is the first fingerprint feature in fig. 5, the fingerprint information in the stripe 1 and the stripe 2 are both from the same bright stripe detection light which is irradiated on the target object, and the detection light reflected by the target object enters the image collector through the anti-counterfeiting detection light spot.

In fig. 4 and 5, the characteristic of each column of light spots is different, it is assumed that the

fingerprint characteristics

②, ④ and ⑥ in fig. 4 are the first fingerprint characteristics corresponding to the bright stripes, and the characteristic parameters of the first fingerprint characteristics, namely, the brightness and darkness contrast of the ridges, are relatively large and can be distinguished by naked eyes, while the fingerprint information also exists in the

first fingerprint characteristics

②, ④ and ⑥ corresponding to fig. 4 in fig. 5, but the characteristic parameters of the first fingerprint characteristics, namely, the brightness and darkness contrast of the ridges, are relatively weak and cannot be distinguished by naked eyes.

Of course, in the anti-counterfeit image, in order to distinguish whether the target object is a two-dimensional finger or a three-dimensional finger, the anti-counterfeit image includes at least one first fingerprint feature and at least one second fingerprint feature that are separated from each other corresponding to the same light-emitting area. In the above embodiments, a plurality of light emitting areas are exemplified, so that each light emitting area has its corresponding first fingerprint feature and second fingerprint feature. When a plurality of first fingerprint features and second fingerprint features exist in the anti-counterfeiting image, more comparison and reference data are provided for anti-counterfeiting judgment, and the accuracy of anti-counterfeiting judgment can be further improved. The scope of the present application is not limited herein to the inclusion of a plurality of mutually separated first and second fingerprint features corresponding to a plurality of luminescent areas in a security image.

In the embodiment illustrated above, the obtained anti-counterfeiting image without being processed by the near algorithm can use the difference of the characteristic parameter of the light-dark contrast of the valley and the ridge in the first fingerprint feature to distinguish whether the target object is a two-dimensional finger or a three-dimensional finger. Specifically, a threshold value may be set for the characteristic parameter, and when the characteristic parameter is smaller than a certain value, it is determined that the target object is a two-dimensional finger; and when the characteristic parameter is larger than a certain threshold value, judging that the target object is a three-dimensional finger.

In other embodiments, the image obtained by the image collector may be processed by an algorithm to be more optimized, so as to improve the accuracy of the determination.

Specifically, a set of reference maps may be collected and stored in advance, and then it may be further determined whether the 2D fake fingerprint is identified based on the reference maps. The reference image may be a light spot image obtained by performing multiple times of real finger pressing using the anti-counterfeiting detection light spot B. The reference image is used to deduct the differences of dynamic background, ambient light, shading, etc.

The acquired anti-counterfeiting image can be subjected to benchmark deduction by using a preset benchmark image, and the anti-counterfeiting image is converted into a de-noising enhanced image. And judging whether the acquired anti-counterfeiting image is a 2D false fingerprint or not according to the de-noised enhanced image.

Specifically, please refer to fig. 6 and 7, for example, the

regions

① and ⑤ in fig. 6 show the second fingerprint features corresponding to different light-emitting stripe regions, the second fingerprint features are fingerprint features formed by small-angle reflection signals, the gray level difference of the ridges is small, and the fingerprint features disappear after the base map is subtracted, while the

regions

②, ④ and ⑥ show the first fingerprint features corresponding to ②, ④ and ⑥ in fig. 4, the fingerprint features formed by large-angle reflection signals, so the gray level difference of the ridges is large, and the fingerprint features are still remained after the base map is subtracted.

By subtracting the reference map, a set of spots of the 2D false fingerprint all exhibit fingerprint features, as shown in fig. 7, the first fingerprint feature and the second fingerprint feature have little difference between each other and before.

Therefore, the fingerprint anti-counterfeiting method provided in this embodiment may further determine that the target object is a two-dimensional finger or a three-dimensional finger according to the difference of the second fingerprint features in the acquired anti-counterfeiting image determined by the denoising enhanced image. Specifically, whether local distortion exists in the second fingerprint feature can be identified, and if the local distortion does not exist, the two-dimensional false fingerprint is determined. Or, the judgment can be carried out according to the difference degree of the brightness of the valleys and the ridges in the identified first fingerprint characteristics.

In both of the above-exemplified embodiments, the first fingerprint feature (e.g.,

regions

②, ④, ⑥) and the second fingerprint feature (e.g., regions ①, ⑤) are formed in the security image, wherein the first fingerprint feature can distinguish between a true 3D finger and a false 2D fingerprint in the originally obtained image according to the principles set forth above, in addition, in another embodiment, the second fingerprint feature can extract a certain security feature after the security image is processed by an algorithm, and in the bright-dark region of the security detection spot B, the second fingerprint feature is very sensitive to the height information of the reflection surface according to the imaging principle, and is mainly represented by the height difference between the valleys and ridges of the surface texture of the true 3D finger, and the fingerprint pattern formed at the edge of the spot is distorted, so that the distorted feature can be identified by the algorithm for the second fingerprint feature (e.g., regions ①, ⑤).

In other embodiments of the anti-counterfeiting method of the present application, due to different algorithms of the anti-counterfeiting image, the difference between the first fingerprint feature and/or the second fingerprint feature in the anti-counterfeiting pattern may be different, and although only two ways of extracting the first fingerprint feature or the second fingerprint feature respectively correspond to the difference between the two-dimensional finger and the three-dimensional finger are illustrated, the disclosure is not limited thereto.

In a practical application scene, the fingerprint anti-counterfeiting method provided by the application can be used for carrying out primary fingerprint information identification on a fingerprint image by utilizing the fingerprint identification light spot. If the fingerprint information of the target object is definitely not matched, the anti-counterfeiting detection light spot B does not need to be lightened, and the time is saved. If the fingerprint information obtained by the fingerprint identification light spot on the target object is successfully matched, the anti-counterfeiting detection light spot B can be lightened, whether the finger is two-dimensional finger information or three-dimensional finger information is judged, the situation that the two-dimensional fake finger falsely using the fingerprint of a matched person can successfully unlock the safety equipment is avoided, and the safety degree of fingerprint unlocking of the electronic equipment is improved.

The embodiment of the fingerprint anti-counterfeiting method specifically applied to the electronic equipment for realizing anti-counterfeiting will be described with reference to fig. 8. Based on the flowchart shown in fig. 8, the fingerprint anti-counterfeiting method for the electronic device may include the following steps:

step S11: after receiving a preset starting signal, lightening a fingerprint identification light spot for collecting a fingerprint image;

step S12: collecting a fingerprint image after the fingerprint identification light spot is lightened;

step S13: comparing the acquired fingerprint image with a stored fingerprint image;

step S14: if the comparison is successful, lightening an anti-counterfeiting detection light spot B for collecting an anti-counterfeiting image, wherein the anti-counterfeiting detection light spot B comprises: a light-emitting region and a non-light-emitting region, the area of the light-emitting region being smaller than the area of the non-light-emitting region;

step S15: after the anti-counterfeiting detection light spot B is lightened, an anti-counterfeiting image is collected, wherein the anti-counterfeiting image 6 comprises: separate first and second fingerprint features;

step S16: deducting a benchmark from the acquired anti-counterfeiting image by using a preset benchmark image, and converting the acquired anti-counterfeiting image into a de-noised enhanced image;

step S17: and judging whether the acquired anti-counterfeiting image is a 2D false fingerprint or not according to the de-noising enhanced image.

In this embodiment, each specific step in the above steps may refer to specific descriptions of the above embodiments, and detailed descriptions of the present application are omitted here.

In general, by using the fingerprint anti-counterfeiting method provided by the embodiment of the application, a new light and dark light spot is lightened, and an anti-counterfeiting detection light spot can be collected by using the light spot, wherein target fingerprint information illuminated by at least one light-emitting area in the anti-counterfeiting detection light spot generates an anti-counterfeiting image, and the anti-counterfeiting image comprises a first fingerprint feature and a second fingerprint feature which are separated from each other; the first fingerprint feature and/or the second fingerprint feature are/is used for distinguishing the target object as a three-dimensional finger or a two-dimensional finger fingerprint corresponding to the difference between the target object as a two-dimensional finger and the three-dimensional finger, so that the safety of the fingerprint identification device can be improved.

In some other embodiments, the anti-counterfeit detection spot B may further include any one of the following: the light and dark annular stripe light spots extend from the center to the periphery, and the light and dark grid light spots extend along a first direction and a second direction perpendicular to the first direction; alternatively, the light-emitting region is a plurality of discontinuous light-emitting regions formed on the non-light-emitting region.

As shown in fig. 9, the anti-counterfeit detection light spot B may be a light and dark annular stripe light spot extending from the center to the periphery. When the anti-counterfeiting detection light spot B is the annular stripe light spot, the anti-counterfeiting detection light spot B corresponds to a two-dimensional light spot, and is beneficial to identifying special fingerprints which may not be well identified by some one-dimensional light spots. When the identified fingerprint is a one-dimensional fingerprint and is parallel to the anti-counterfeiting detection light spot B, the two-dimensional light spot is needed to identify.

Specifically, the annular stripe light spot may be annular. Because the brightness attenuation of the lens occurs, the brightness attenuation of the lens can be superposed with the light and shade attenuation of the light spots to cause interference. To avoid the above interference, the center of the annular fringe spot is aligned with the center of the module lens 4.

As shown in fig. 10, the anti-counterfeit detection light spot B may be a grid light spot with alternate light and dark spots extending along a first direction and a second direction perpendicular to the first direction.

As shown in fig. 11, the forgery prevention detection spot B may be a plurality of discontinuous light emitting portions formed on the non-light emitting region. Specifically, the light emitting portion may have a cross shape as shown in fig. 6, but the light emitting portion may have other shapes, and the present application is not limited thereto.

Based on the fingerprint anti-counterfeiting method provided by the embodiment, the application also provides a fingerprint anti-counterfeiting device.

Please refer to fig. 12 for a schematic diagram of an embodiment of the fingerprint anti-counterfeit device in the present application. The fingerprint anti-counterfeiting device can comprise: the device comprises a detection light source 20, a control unit 6, an anti-counterfeiting detection light spot B, an optical function unit 30 and a photosensitive unit 50. In a specific embodiment, the detection light source can be a self-luminous screen such as an OLED screen as the detection light source 20. The OLED screen can be used for forming a fingerprint identification light spot and an anti-counterfeiting detection light spot B. For example, a local area of the OLED screen forms an anti-counterfeiting detection spot B. The local area may be a fingerprint detection area. The control unit 6 can control the fingerprint identification light spot and the anti-counterfeiting detection light spot B to be displayed on the OLED screen. For the same OLED screen, the control unit 6 can control the lighting sequence of the fingerprint identification light spot and the anti-counterfeiting detection light spot B according to a preset sequence. Of course, in other embodiments, the detection light source is not limited to the OLED screen, and may be other detection light sources separately provided for the fingerprint anti-counterfeiting device, which are not listed in detail herein.

Wherein, the control unit 6 controls the detection light source 20 to form the anti-counterfeiting detection light spot B. The control unit 6, as shown in an embodiment shown in fig. 12, may include: a sensor control unit and an electronic equipment control center. The detection light source can be controlled by a sensor control unit and also can be controlled by an electronic equipment control center. The fingerprint authentication device may be provided with a fingerprint identification area capable of transmitting a predetermined signal of a target object to the control unit 6 when the fingerprint identification area receives the signal, for example, a pressing signal of a finger of a user, a touch signal, or the like. After the control unit 6 receives the signal, the detection light source 20 can be controlled to form an anti-counterfeiting detection spot B. In this embodiment, the self-luminous display screen can be directly used as the detection light source 20.

The light emitted from the forgery-prevention detection spot B to the target object is reflected back to form a forgery-prevention image on the photosensitive unit 50 through the forgery-prevention detection spot B and the optical function unit 30. The anti-counterfeiting image acquired by the anti-counterfeiting detection light spot B comprises at least one first fingerprint feature and at least one second fingerprint feature which are separated and presented by the fingerprint area of the target object illuminated by the same light-emitting area of the anti-counterfeiting detection light spot B. The anti-counterfeit image of the photosensitive unit 50 can be transmitted to the control unit 6, and the control unit 6 can determine whether the target object is a three-dimensional real finger or a two-dimensional false fingerprint. Although the optical function unit 30 is disposed directly above the photosensitive unit 50 in this embodiment, in other embodiments, the optical function unit is not necessarily located directly above or slightly shifted due to the difference of the optical path of the reflected fingerprint signal.

In this embodiment, the optical function unit 30 may include an optical lens assembly, among others. Other focusing elements, such as microlenses or other optical elements, under the optical lens may also be included. The optical function unit 30 may be a micro-lens structure and/or a collimating structure, and realizes imaging of the fingerprint signal passing through the anti-counterfeit detection light spot in the photosensitive unit 50.

Specifically, the control unit 6 can store the control logic of the fingerprint anti-counterfeiting method, so that the electronic device that should use the fingerprint identification sensor can execute the steps in the fingerprint anti-counterfeiting method, and the specific identification process is not described herein again. The fingerprint identification device can be an electronic device with a fingerprint identification requirement, such as a mobile phone, a tablet, a computer and the like. The control unit 6 may include an electronic equipment control center and a sensor control unit. Among them, the optical function unit 30, the light sensing unit 50, and the sensor control unit may be integrated in the fingerprint chip module 100.

In addition, the fingerprint anti-counterfeiting device can also comprise a fingerprint identification light spot. The fingerprint identification light spot is used for collecting accurate fingerprint information of the target object, and the function of the fingerprint identification light spot is different from that of the anti-counterfeiting detection light spot. Generally speaking, the pattern of the anti-counterfeiting detection light spot B is different from the pattern of the fingerprint identification light spot. The pattern of the anti-counterfeiting detection light spot is mainly used for distinguishing whether the fingerprint of the target object is two-dimensional fingerprint information or three-dimensional fingerprint information.

In general, the fingerprint anti-counterfeiting device can achieve the technical effect that the fingerprint anti-counterfeiting method can achieve, and for the specific setting and identification principle, reference is made to the specific description of the fingerprint anti-counterfeiting method, which is not repeated herein.

All articles and references disclosed, including patent applications and publications, are hereby incorporated by reference for all purposes. The term "consisting essentially of …" describing a combination shall include the identified element, ingredient, component or step as well as other elements, ingredients, components or steps that do not materially affect the basic novel characteristics of the combination. The use of the terms "comprising" or "including" to describe combinations of elements, components, or steps herein also contemplates embodiments that consist essentially of such elements, components, or steps. By using the term "may" herein, it is intended to indicate that any of the described attributes that "may" include are optional. A plurality of elements, components, parts or steps can be provided by a single integrated element, component, part or step. Alternatively, a single integrated element, component, part or step may be divided into separate plural elements, components, parts or steps. The disclosure of "a" or "an" to describe an element, ingredient, component or step is not intended to foreclose other elements, ingredients, components or steps.

The embodiments in the present specification are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other. The above embodiments are merely illustrative of the technical ideas and features of the present invention, and the purpose thereof is to enable those skilled in the art to understand the contents of the present invention and implement the present invention, and not to limit the protection scope of the present invention. All equivalent changes and modifications made according to the spirit of the present invention should be covered within the protection scope of the present invention.

Claims

1. A fingerprint anti-counterfeiting method is characterized by comprising the following steps:

2. The fingerprint authentication method of claim 1, wherein the area of the non-light emitting area is larger than the area of the light emitting area.

3. The fingerprint anti-counterfeiting method according to claim 2, wherein the area ratio of the light-emitting areas to the non-light-emitting areas in the pattern of the anti-counterfeiting detection light spot is greater than 1:19 and less than 1: 1.

4. The fingerprint anti-counterfeiting method according to claim 2, wherein the anti-counterfeiting detection light spots are striped light spots with alternate light and shade.

5. The fingerprint authentication method of claim 4, wherein the ratio of the width of the light stripe to the width of the dark stripe in the stripe light spot is 3: 17.

6. The fingerprint anti-counterfeiting method according to claim 2, wherein the anti-counterfeiting detection light spot further comprises any one of the following:

light and shade alternate annular stripe light spots extending from the center to the periphery; or grid light spots which are arranged in a dark and bright mode and extend along a first direction and a second direction perpendicular to the first direction; alternatively, the light-emitting region is a plurality of discontinuous light-emitting regions formed on the non-light-emitting region.

7. The fingerprint anti-counterfeiting method according to claim 1, further comprising: and forming a fingerprint identification light spot to illuminate the target object so as to acquire fingerprint information of the target object.

8. The fingerprint authentication method of claim 1, wherein processing the information of the first fingerprint feature and/or the second fingerprint feature comprises extracting a difference parameter corresponding to a two-dimensional finger and a three-dimensional finger, respectively, in the first fingerprint feature and/or the second fingerprint feature.

9. The fingerprint authentication method of claim 1, further comprising: and preprocessing the anti-counterfeiting image to obtain a converted anti-counterfeiting image, and processing the information of the first fingerprint characteristic and/or the second fingerprint characteristic in the converted anti-counterfeiting image to distinguish that the target object is a three-dimensional finger or a two-dimensional finger.

10. A fingerprint security device, comprising: the device comprises a detection light source, a control unit, an anti-counterfeiting detection light spot, an optical function unit and a photosensitive unit; wherein,

11. The fingerprint anti-counterfeiting device according to claim 10, further comprising a fingerprint identification light spot for collecting fingerprint information of the target object, wherein the pattern of the anti-counterfeiting detection light spot is different from the pattern of the fingerprint identification light spot.

12. The fingerprint authentication device of claim 10, wherein the authentication detection spot has a light emitting area and a non-light emitting area, the light emitting area being smaller than the non-light emitting area.

13. The fingerprint authentication device of claim 12, wherein said authentication detection spot is a pattern of alternating light and dark stripes, and the area of the dark stripes is greater than the area of the light stripes.

14. The fingerprint security device of claim 13, wherein the ratio of the area of the dark stripes to the area of the light stripes is greater than 1:19 and less than 1: 1.

15. The fingerprint authentication device of claim 10, wherein said detection light source is a light source of an OLED screen.

16. The fingerprint security device of claim 11, wherein the optical function unit comprises an optical lens assembly.