Optical fingerprint recognition and anti-counterfeiting method and system

Abstract

The present invention discloses an optical fingerprint recognition and anti-counterfeiting method and system, the method comprising: forming a fingerprint recognition light spot, forming an anti-counterfeiting detection light spot with a preset pattern, providing a photosensitive unit, receiving fingerprint information carried by a target object under the irradiation of the fingerprint recognition light spot and the anti-counterfeiting detection light spot respectively, the fingerprint information carried by the target object under the irradiation of the anti-counterfeiting detection light spot received by the photosensitive unit forms a fingerprint anti-counterfeiting image; judging the target object as a two-dimensional finger or a three-dimensional finger according to the fingerprint anti-counterfeiting image; the preset pattern of the anti-counterfeiting detection light spot includes a first detection area and a second detection area with different luminous intensities; extracting the differential feature parameters corresponding to the two-dimensional finger and the three-dimensional finger in the fingerprint anti-counterfeiting image to judge the target object as a two-dimensional finger or a three-dimensional finger. The present invention can accurately identify 2D fake fingerprints, thereby improving the security of fingerprint recognition equipment.

Description

Technical Field

[0001] The present invention relates to the field of optical fingerprint recognition, and in particular to an optical fingerprint recognition and anti-counterfeiting method and system. Background Art

[0002] With the rapid development of communication technology, users have an increasing demand for mobile terminals, and their requirements for the user experience of mobile terminals are also getting higher and higher. In order to better meet the needs of users, fingerprint recognition, as a relatively mature biometric technology, has been widely used in mobile terminals. Among them, the core part of mobile terminals to realize fingerprint recognition is the optical fingerprint sensor.

[0003] like Figure 1 As shown, a general optical fingerprint sensor includes: a sensor pixel array, a lens 4, a light shielding layer 3, an OLED (Organic Light-Emitting Diode) screen and a transparent layer 1. When in use, the front of the OLED screen 2 emits a detection light, which is reflected by the finger pressed on the screen and converges to the sensor pixel array under the lens 4 through the OLED screen 2. After receiving the detection light, the sensor pixel array can obtain an optical image representing the fingerprint. Since the intensity of light reflected by the peaks and troughs of the fingerprint is different, a clear fingerprint texture image can be taken. Among them, the fingerprint texture image is a two-dimensional grayscale image.

[0004] However, the applicant found that: since the fingerprint texture image corresponding to the fingerprint signal carried by the finger reflected light is a grayscale image, it can only reflect the plane contrast. Therefore, it is easy to be attacked by 2D (two-dimensional plane) fake fingerprints, resulting in insufficient device security of the optical fingerprint sensor. Summary of the invention

[0005] Based on the above-mentioned defects of the prior art, the technical problem to be solved by the embodiments of the present invention is to provide an optical fingerprint recognition and anti-counterfeiting method and system, which can accurately identify 2D fake fingerprints, thereby improving the security of fingerprint recognition equipment.

[0006] The specific technical solution of the implementation mode of the present invention is:

[0007] An optical fingerprint recognition and anti-counterfeiting method, comprising:

[0008] forming a fingerprint recognition light spot, and irradiating a target object with the fingerprint recognition light spot;

[0009] Forming an anti-counterfeiting detection light spot having a preset pattern, and irradiating a target object with the anti-counterfeiting detection light spot;

[0010] Providing a photosensitive unit, respectively receiving the fingerprint information carried by the target object under the illumination of the fingerprint recognition light spot and the anti-counterfeiting detection light spot, the fingerprint information carried by the target object under the illumination of the anti-counterfeiting detection light spot received by the photosensitive unit forms a fingerprint anti-counterfeiting image;

[0011] The target object is judged to be a two-dimensional finger or a three-dimensional finger based on the fingerprint anti-counterfeiting image; wherein the preset pattern of the anti-counterfeiting detection light spot includes a first detection area and a second detection area with different luminous intensities; and the differentiated feature parameters corresponding to the two-dimensional finger and the three-dimensional finger in the fingerprint anti-counterfeiting image are extracted to judge the target object to be a two-dimensional finger or a three-dimensional finger.

[0012] In a preferred embodiment, the luminescence intensity of the first detection zone is greater than the luminescence intensity of the second detection zone, and the luminescence intensity of the second detection zone is zero.

[0013] In a preferred embodiment, the area of ​​the first detection zone is larger than the area of ​​the second detection zone.

[0014] In a preferred embodiment, the second detection areas are discretely distributed in the anti-counterfeiting detection light spot.

[0015] In a preferred embodiment, the differential characteristic parameter includes: the grayscale value or grayscale value contrast of the fingerprint image of the anti-counterfeiting area corresponding to the preset pattern anti-counterfeiting detection spot in the fingerprint anti-counterfeiting image.

[0016] In a preferred embodiment, the optical fingerprint recognition and anti-counterfeiting method may further include setting a threshold range for the differential feature parameter, and determining whether the target object is a two-dimensional finger or a three-dimensional finger based on whether the differential feature parameter is within the threshold range.

[0017] In a preferred embodiment, the fingerprint anti-counterfeiting image includes a first imaging area corresponding to the first detection area, a transition area adjacent to the first imaging area, and a second imaging area corresponding to the second detection area; the transition area is located between the first imaging area and the second imaging area.

[0018] In a preferred embodiment, the anti-counterfeiting detection light spot of the preset pattern includes a plurality of discrete second detection areas.

[0019] An optical fingerprint recognition and anti-counterfeiting system is applied to an electronic device having a fingerprint recognition area, comprising: an optical recognition and anti-counterfeiting device and a control unit;

[0020] The optical recognition and anti-counterfeiting device comprises:

[0021] A detection light source, the detection light source irradiates the object to be identified on the fingerprint identification area of ​​the electronic device;

[0022] An optical functional unit, disposed below the fingerprint recognition area, receiving a light signal reflected by the object to be recognized; and

[0023] A photosensitive unit, disposed below the optical functional unit, receiving the optical signal processed by the optical functional unit to form a fingerprint sensing image;

[0024] Wherein, the control unit controls the detection light source to serve as an identification light source and an anti-counterfeiting light source respectively; when the electronic device performs fingerprint identification and anti-counterfeiting on the identification object, the system controls the detection light source to form an anti-counterfeiting detection light spot of a preset pattern; the preset pattern of the anti-counterfeiting detection light spot includes a first detection area and a second detection area with different luminous intensities; the control unit extracts the anti-counterfeiting feature parameters in the fingerprint sensing image output by the photosensitive unit corresponding to the anti-counterfeiting detection light spot to determine whether the object to be identified is a two-dimensional image or a three-dimensional image. In a preferred embodiment, the fingerprint sensing image output by the photosensitive unit corresponding to the anti-counterfeiting detection light spot includes a first imaging area corresponding to the first detection area, a transition area adjacent to the first imaging area, and a second imaging area corresponding to the second detection area; the transition area is located between the first imaging area and the second imaging area.

[0025] In a preferred embodiment, the luminescence intensity of the first detection zone is greater than the luminescence intensity of the second detection zone, and the luminescence intensity of the second detection zone is zero.

[0026] The technical solution of the present invention has the following significant beneficial effects:

[0027] An embodiment of the present invention provides an optical fingerprint recognition and anti-counterfeiting method and system, which utilizes an anti-counterfeiting detection light spot with a preset pattern to illuminate a target object, and utilizes a photosensitive unit to respectively receive fingerprint information carried by the target object under the illumination of the fingerprint recognition light spot. The fingerprint information carried by the target object under the illumination of the anti-counterfeiting detection light spot received by the photosensitive unit forms a fingerprint anti-counterfeiting image; subsequently, the differentiated feature parameters corresponding to the two-dimensional finger and the three-dimensional finger in the fingerprint anti-counterfeiting image are extracted to determine whether the target object is a two-dimensional finger or a three-dimensional finger, thereby improving the security of the fingerprint recognition device.

[0028] With reference to the following description and drawings, specific embodiments of the present invention are disclosed in detail, indicating the manner in which the principles of the present invention can be adopted. It should be understood that the embodiments of the present invention are not limited in scope. Within the spirit and scope of the appended claims, the embodiments of the present invention include many changes, modifications and equivalents. Features described and / or shown for one embodiment can be used in one or more other embodiments in the same or similar manner, combined with features in other embodiments, or replace features in other embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The accompanying drawings described herein are only for explanation purposes and are not intended to limit the scope of the present invention in any way. In addition, the shapes and proportional dimensions of the various components in the figures are only schematic, used to help understand the present invention, and are not specifically limited to the shapes and proportional dimensions of the various components of the present invention. Those skilled in the art can select various possible shapes and proportional dimensions to implement the present invention according to the teachings of the present invention.

[0030] Figure 1 It is a structural schematic diagram of an OLED screen under-module in the prior art;

[0031] Figure 2 A flowchart of the steps of the optical fingerprint recognition and anti-counterfeiting method provided in an embodiment of the present invention;

[0032] Figure 3 A schematic diagram of a first anti-counterfeiting detection light spot provided in an embodiment of the present invention;

[0033] Figure 4 It is an anti-counterfeiting image formed by a 3D real finger;

[0034] Figure 5 It is an anti-counterfeiting image formed by a 2D fake fingerprint;

[0035] Figure 6 for Figure 4 A denoised and enhanced image formed by deducting a reference from an anti-counterfeiting image formed by a 3D real finger;

[0036] Figure 7 for Figure 5 A denoised and enhanced image formed by deducting the reference from the anti-counterfeiting image formed by a 2D fake fingerprint;

[0037] Figure 8 A schematic diagram of a second anti-counterfeiting detection light spot provided in an embodiment of the present invention;

[0038] Fig. 9 A schematic diagram of a third anti-counterfeiting detection light spot provided in an embodiment of the present invention;

[0039] Fig.10 A schematic diagram of a fourth anti-counterfeiting detection light spot provided in an embodiment of the present invention;

[0040] Fig.11 A schematic diagram of a fifth anti-counterfeiting detection light spot provided in an embodiment of the present invention;

[0041] Fig.12 Corresponding to the photosensitive unit Fig.11 The fingerprint anti-counterfeiting image is formed when the anti-counterfeiting detection light spot is irradiated onto the target object;

[0042] Fig.13 Two-dimensional finger on white background Fig.11 The fingerprint anti-counterfeiting image formed by the photosensitive unit under the irradiation of the anti-counterfeiting detection light spot;

[0043] Fig.14 For three-dimensional fingers Fig.11 The fingerprint anti-counterfeiting image formed by the photosensitive unit under the irradiation of the anti-counterfeiting detection light spot;

[0044] Fig.15 A schematic diagram showing the comparison of the grayscale change from the center to the edge of a 3D finger and a white 2D finger;

[0045] Fig.16 For the red two-dimensional finger Fig.11 The fingerprint anti-counterfeiting image formed by the photosensitive unit under the irradiation of the anti-counterfeiting detection light spot;

[0046] Fig.17 For three-dimensional fingers Fig.11 The fingerprint anti-counterfeiting image formed by the photosensitive unit under the irradiation of the anti-counterfeiting detection light spot;

[0047] Fig.18 A schematic diagram showing the comparison of the grayscale change from the center to the edge of a 3D finger and a red 2D finger;

[0048] Fig.19 A schematic diagram of a sixth anti-counterfeiting detection light spot provided in an embodiment of the present invention;

[0049] Fig. 20 A schematic diagram of a seventh anti-counterfeiting detection light spot provided in an embodiment of the present invention;

[0050] Fig.21 A schematic diagram of an eighth anti-counterfeiting detection light spot provided in an embodiment of the present invention;

[0051] Fig. 22 It is a module diagram of the optical fingerprint recognition and anti-counterfeiting system provided in an embodiment of the present invention.

[0052] Reference numerals of the above drawings:

[0053] 1. Transparent layer; 2. OLED screen; B. Anti-counterfeiting detection light spot; 3. Shading layer; 4. Lens; 5. Pixel; 20. Detection light source; 30. Optical functional unit; 50. Photosensitive unit; 6. Control unit; 21. First detection area; 22. Second detection area; 23. Effective anti-counterfeiting detection area; 51. First imaging area; 52. Second imaging area; 53. Transition area. DETAILED DESCRIPTION

[0054] The technical solution of the present invention will be described in detail below in conjunction with the accompanying drawings and specific implementation methods. It should be understood that these implementation methods are only used to illustrate the present invention and are not used to limit the scope of the present invention. After reading the present invention, various equivalent forms of modifications to the present invention by those skilled in the art all fall within the scope defined by the claims attached to this application.

[0055] It should be noted that when an element is referred to as being "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.

[0056] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0057] The embodiments of the present invention provide an optical fingerprint recognition and anti-counterfeiting method and system, which can accurately distinguish or determine whether it is a two-dimensional fingerprint or a three-dimensional fingerprint, avoid using two-dimensional fingerprint information instead of three-dimensional fingerprint for fingerprint recognition or unlocking, and improve the security of fingerprint recognition.

[0058] Here, the optical fingerprint recognition and anti-counterfeiting method is applied to a mobile communication device as an example, but the optical fingerprint recognition and anti-counterfeiting method is not limited to being applied to other electronic devices, such as fingerprint locks, or other electronic devices that require fingerprints for identification and unlocking.

[0059] Among commonly used mobile communication devices, the display screen of the mobile phone is more commonly an OLED screen. According to the introduction of the OLED screen in the prior art, the OLED screen can be understood as a kind of self-luminous display screen. Therefore, in the introduction of this embodiment, the OLED screen can be used as a detection light source for fingerprint detection. For example, on the OLED screen of a mobile phone, the OLED pixel array in the fingerprint sensing area can emit a light spot to illuminate the finger to collect the user's fingerprint. The conventional light spot used to collect the fingerprint image can be circular or other shapes, and is referred to as the fingerprint recognition light spot below.

[0060] The fingerprint recognition light spot can be a light spot of any preset pattern, or a full-bright light spot, which is not limited here. When performing fingerprint recognition, since it is necessary to extract the subtle fingerprint features of the recognition object, the full-bright light spot is a common form of fingerprint recognition light spot. For example, the fingerprint recognition light spot may include any of the following: forming a pure color light spot with the same brightness in the fingerprint recognition area, for example, a light spot formed by a single color such as red, green, blue, etc., or a composite color light spot formed by a combination of different colors in a predetermined proportion. For an optical fingerprint recognition device, when the main body of the optical processing component above the photosensitive unit is an optical lens, in order to solve the relative illumination problem of the optical lens, the fingerprint recognition light spot can be a gradient light spot. A gradient light spot with brightness gradually brightening from the center to the periphery is formed in the fingerprint recognition area. Among them, the size, shape, arrangement, etc. of the gradient light spot used for fingerprint recognition can vary according to the composition distribution of the hardware structure of the device. Among them, when the fingerprint recognition light spot is a gradient light spot that gradually brightens from the center to the periphery, the brightness of the center and edge areas of the fingerprint image collected by the photosensitive unit can be uniform, thereby alleviating the relative illumination problem of the optical lens.

[0061] It should be noted that in the optical fingerprint recognition and anti-counterfeiting method involved in this application, fingerprint anti-counterfeiting and fingerprint recognition are performed separately. The fingerprint recognition light spot is used for fingerprint recognition, and the anti-counterfeiting detection light spot with a preset pattern is used for anti-counterfeiting to determine whether the target object to be recognized is a two-dimensional finger or a three-dimensional finger. Whether to recognize first or then anti-counterfeiting, or first anti-counterfeiting and then recognition, can be specifically set according to the specific application scenario of the optical fingerprint recognition and anti-counterfeiting method, and is not limited in this application.

[0062] The optical fingerprint recognition and anti-counterfeiting method involved in the present application is described below with reference to specific drawings and some specific embodiments.

[0063] See also Figure 2 In an embodiment of the present application, an optical fingerprint recognition and anti-counterfeiting method is provided, which may include:

[0064] Step S11: forming a fingerprint recognition light spot, and using the fingerprint recognition light spot to illuminate a target object;

[0065] Step S13: forming an anti-counterfeiting detection light spot having a preset pattern, and irradiating a target object with the anti-counterfeiting detection light spot;

[0066] Step S15: providing a photosensitive unit to receive fingerprint information of the target object under the illumination of the fingerprint recognition light spot and the anti-counterfeiting detection light spot respectively, and the fingerprint information of the target object under the illumination of the anti-counterfeiting detection light spot received by the photosensitive unit forms a fingerprint anti-counterfeiting image;

[0067] Step S17: Determine whether the target object is a two-dimensional finger or a three-dimensional finger based on the fingerprint anti-counterfeiting image; wherein the preset pattern of the anti-counterfeiting detection light spot includes a first detection area 21 and a second detection area 22 with different luminous intensities; extract the differentiated feature parameters corresponding to the two-dimensional finger and the three-dimensional finger in the fingerprint anti-counterfeiting image to determine whether the target object is a two-dimensional finger or a three-dimensional finger.

[0068] In a specific implementation, optical fingerprint recognition and anti-counterfeiting are further described. To perform fingerprint recognition, a fingerprint recognition light spot needs to be formed in the fingerprint recognition area, and the fingerprint recognition light spot is used to illuminate the target object. When performing fingerprint anti-counterfeiting, an anti-counterfeiting detection light spot with a preset pattern is formed in the fingerprint recognition area, and the anti-counterfeiting detection light spot is used to illuminate the target object.

[0069] In a specific embodiment of the optical fingerprint recognition and anti-counterfeiting method described herein, the method will utilize an optical fingerprint recognition and anti-counterfeiting device. This optical fingerprint recognition and anti-counterfeiting device will include a photosensitive unit. The photosensitive unit is usually presented in the form of a semiconductor chip in the optical fingerprint recognition and anti-counterfeiting device, and is used to receive the light signal reflected by the target object and the light signal processed by the optical function unit of the optical fingerprint recognition and anti-counterfeiting device to perform optical imaging. When performing fingerprint recognition, the photosensitive unit receives the fingerprint information carried by the target object when irradiated by the fingerprint recognition light spot. When performing fingerprint anti-counterfeiting, the photosensitive unit receives the fingerprint information carried by the target object under the irradiation of the anti-counterfeiting detection light spot to form a fingerprint anti-counterfeiting image. Based on the fingerprint anti-counterfeiting image, it is judged whether the target object is a two-dimensional finger or a three-dimensional finger.

[0070] The preset pattern of the anti-counterfeiting detection light spot includes a first detection area and a second detection area with different luminous intensities; the differential feature parameters corresponding to the two-dimensional finger and the three-dimensional finger in the fingerprint anti-counterfeiting image are extracted to determine whether the target object is a two-dimensional finger or a three-dimensional finger. The following takes some specific preset patterns of anti-counterfeiting detection light spots as examples and explanations.

[0071] See also Figure 3The preset pattern of the anti-counterfeiting detection light spot shown. The first detection area is a thin strip that emits light, and the second detection area is a thick strip that does not emit light. The first detection area and the second detection area are alternately and repeatedly arranged to form the anti-counterfeiting detection light spot B of this preset pattern.

[0072] Figure 4 to Figure 7 The target object is received by the photosensitive unit. Figure 3 The fingerprint anti-counterfeiting image is formed by the anti-counterfeiting detection spot B of the preset pattern. Figure 6 and Figure 7 It is an image after the fingerprint anti-counterfeiting image is processed by the control unit in the electronic device. Figure 4 and Figure 5 It is the fingerprint anti-counterfeiting image formed by the photosensitive unit. Figure 4 When the target object is a 3D finger, the target object is Figure 3 The fingerprint anti-counterfeiting image is formed under the illumination of the anti-counterfeiting detection light spot of the preset pattern shown. Figure 5 When the target object is a two-dimensional finger, the target object is Figure 3 The fingerprint anti-counterfeiting image is formed under the irradiation of the anti-counterfeiting detection light spot of the preset pattern shown. It can be understood that Figure 4 and Figure 5 The middle bright light stripes ①③⑤⑦ are the first imaging area corresponding to the first detection area of ​​the anti-counterfeiting detection spot B. Since the luminous intensity of the second detection area is zero, Figure 4 and Figure 5 The dark area without fingerprints can be understood as the second imaging area corresponding to the second detection of the anti-counterfeiting detection spot B. Figure 4 and Figure 5 It can be seen that there are obvious differences in the transition area ②④⑥ between the first imaging area and the second imaging area. Figure 4 and Figure 5 The fingerprint anti-counterfeiting image is optimized by algorithm and the corresponding Figure 6 and Figure 7 It can be seen that Figure 6 The fingerprint features in the transition region shown in Figure 7 The fingerprint characteristics of the transition zone shown in are obviously different.

[0073] Those skilled in the art can determine whether the target object is a two-dimensional finger or a three-dimensional finger by extracting the differential feature parameters corresponding to the two-dimensional finger and the three-dimensional finger in the fingerprint anti-counterfeiting image. For example, a threshold range is set for the contrast of the fingerprint valley ridge in the transition zone, or by extracting the slope of the fingerprint information change in the transition zone. Since the difference can be distinguished by the naked eye, the control unit can use different algorithms to extract differential features and realize the identification of two-dimensional and three-dimensional target objects. Here, no further examples are given for the extraction of this differential feature.

[0074] Therefore, using Figure 3 The anti-counterfeiting detection light spot B of the preset pattern shown can realize the three-dimensional and two-dimensional identification of the target object. The main body of the optical functional unit in the optical fingerprint recognition and anti-counterfeiting device verified by the anti-counterfeiting detection light spot B of this anti-counterfeiting pattern is an optical lens. For optical fingerprint recognition and anti-counterfeiting devices such as optical lenses. When the anti-counterfeiting detection light spot B of the preset pattern illuminates a two-dimensional finger and a three-dimensional finger, there will be a more obvious difference in the fingerprints corresponding to the transition zone between the first detection area and the second detection area on the photosensitive unit. By using the difference in this image to extract the differentiation parameters, it can be determined whether the target object is a two-dimensional finger or a three-dimensional finger.

[0075] Figures 8 to 10 Further, various patterns of anti-counterfeiting detection light spots B are listed. Fig.10 As shown, the anti-counterfeiting detection light spot B can be a light spot with alternating light and dark annular stripes extending from the center to the periphery. When the anti-counterfeiting detection light spot B is the above-mentioned annular stripe light spot, it corresponds to a two-dimensional light spot, which is conducive to expanding the differentiated fingerprint features of different dimensions of the fingerprint anti-counterfeiting image. Figure 8 As shown, the anti-counterfeiting detection light spot B may be a grid light spot with alternating light and dark extending along a first direction and a second direction perpendicular to the first direction. Fig. 9 As shown in FIG. 1 , the anti-counterfeiting detection light spot B may be a plurality of discontinuous light-emitting portions formed on the non-light-emitting area. Specifically, the light-emitting portion may be Fig. 9 The "cross" shape shown in the figure, of course, the light-emitting portion can also be in other shapes, and the present application does not make any specific limitation here.

[0076] For the photosensitive unit Figures 8 to 10 The fingerprint anti-counterfeiting images formed are not illustrated one by one. In general, the anti-counterfeiting detection light spots B of the above patterns are Figure 3 Similar to the striped anti-counterfeiting detection spot shown, for two-dimensional and three-dimensional target objects, the transition area between the first imaging area and the second imaging area of ​​the corresponding photosensitive unit will also produce differentiated fingerprint images, thereby also realizing the identification of whether the target object is a two-dimensional finger or a three-dimensional finger.

[0077] like Figure 3 As shown, the anti-counterfeiting detection spot B can be a light spot with alternating light and dark stripes extending along the first direction, including light stripes and dark stripes. Compared with the anti-counterfeiting detection spots of other listed patterns, the anti-counterfeiting detection spot B of this pattern has better robustness due to lower calibration requirements between system positions. In the anti-counterfeiting retrieval spot of this preset pattern, the area of ​​the dark stripes is greater than the area of ​​the light stripes, and the width ratio of the light stripes to the dark stripes can be 3:17.

[0078] In this embodiment, the anti-counterfeiting detection light spot B can be a one-dimensional light spot, for example, a line pair light spot, such as Figure 3As shown, on the one hand, it is conducive to reducing the complexity of subsequent image and data processing, and on the other hand, it is also conducive to ensuring the accuracy and reliability of fingerprint anti-counterfeiting identification. In addition, the cost of forming the anti-counterfeiting detection spot B is also relatively low. The anti-counterfeiting detection spot B has a light spot with alternating light and dark stripes extending along the first direction. The bright stripes and dark stripes of the striped light spot are parallel to each other. It was found through experiments that the width ratio of the bright stripes to the dark stripes is 3:17, which is conducive to forming an anti-counterfeiting image that can significantly identify 2D fake fingerprints (i.e., two-dimensional fake fingers). However, when the algorithm anti-counterfeiting module in the control unit of the electronic device is more powerful, even if there is no significant fingerprint difference between the two-dimensional fake finger and the three-dimensional finger for the two-dimensional and three-dimensional models of the same fingerprint in the fingerprint anti-counterfeiting image, its subtle differentiated fingerprint feature parameters can also be extracted for anti-counterfeiting.

[0079] The luminous brightness of the second detection area in the pattern of the anti-counterfeiting detection spot B listed above is zero. The formation of such a pattern is relatively easy to control and implement for forming an anti-counterfeiting detection spot B of a preset pattern. In particular, when the anti-counterfeiting detection spot B utilizes the luminous pixels of the fingerprint recognition area in the OLED display screen to implement the pattern of the anti-counterfeiting detection spot B listed above, when the brightness of the second detection area is zero, the control of the anti-counterfeiting detection spot B of the various patterns listed above can be simple and easy to implement. It should be understood that in other embodiments, the luminous brightness of the second detection area in the pattern of the anti-counterfeiting detection spot B can also be lower than that of the first detection area, so that the first detection area and the second detection area can still form an anti-counterfeiting detection spot B of a preset pattern. The anti-counterfeiting detection spot B of the preset pattern can also cause two-dimensional target objects and three-dimensional target objects to produce differentiated fingerprint images on the photosensitive unit.

[0080] Although the anti-counterfeiting detection light spots B of the patterns listed above have fingerprint differences in the transition area in the fingerprint anti-counterfeiting images formed by the photosensitive unit for the two-dimensional and three-dimensional target objects of the same fingerprint. However, since the anti-counterfeiting detection light spots B of the above patterns are all dark areas with larger areas than bright areas, when the anti-counterfeiting detection light spots B of this pattern are irradiated to the target object, the photosensitive unit needs a longer exposure time to form a fingerprint anti-counterfeiting image, which can easily lead to a slightly longer time when using such anti-counterfeiting detection light spots B for fingerprint anti-counterfeiting identification. Since fingerprint recognition and anti-counterfeiting are two separate processes, it will take longer than expected for electronic devices to apply this optical fingerprint recognition and anti-counterfeiting method, which can easily lead to a slightly poor end-user experience.

[0081] In order to solve the problem that the exposure time is too long when the photosensitive unit forms a fingerprint anti-counterfeiting image due to the anti-counterfeiting detection spot B of this type of pattern with a large dark area, an anti-counterfeiting detection spot B with a larger bright area is proposed below, which can enable two-dimensional fingers and three-dimensional fingers to form differentiated fingerprint anti-counterfeiting images on the photosensitive unit.

[0082] See also Fig.11 The anti-counterfeiting detection spot B of the pattern shown in FIG. The middle of the anti-counterfeiting detection spot B is the second detection area 22, and the first detection area 21 is outside the second detection area 22. Fig.11 The anti-counterfeiting detection spot B shown is Fig.10 Compared with the anti-counterfeiting detection spot B pattern shown in FIG. 1 , the second detection area 22 in the shape of a ring around the middle is missing. Fig.11 The anti-counterfeiting detection spot B of the pattern shown is relatively Fig.10 As shown, the area proportion of the second detection area 22 in the entire anti-counterfeiting detection spot B is reduced, while the area proportion of the first detection area 21 with brighter brightness is increased, which can help reduce the exposure time required for the photosensitive unit to form a fingerprint anti-counterfeiting image. Fig.11 The second detection area 22 of the anti-counterfeiting detection light spot B shown does not emit light for illustration.

[0083] like Fig.12 Shown Fig.11 The anti-counterfeiting detection light spot B of the preset pattern is irradiated to the target object, and the fingerprint anti-counterfeiting image is formed by the corresponding photosensitive unit. The second imaging area 52 is the imaging position corresponding to the second detection area 22 in the photosensitive unit, and the first imaging area 51 is the imaging position corresponding to the first detection area 21 in the photosensitive unit. There is a transition area 53 between the first imaging area 51 and the second imaging area 52.

[0084] Combined with reference Fig.13 , Fig.14 and Fig.16 , Fig.17 , Fig.12 , Fig.13 , Fig.14 as well as Fig.16 and Fig.17 Both Fig.11 The anti-counterfeiting detection spot B of the pattern shown is irradiated onto the fingerprint to be identified to form an anti-counterfeiting image of the fingerprint. Fig.13 , Fig.14 and Fig.16 , Fig.17 In the fingerprint anti-counterfeiting image shown Fig.12 The defined transition region 53 is more distinct. Fig.12 The boundary of the transition area 53 defined in the fingerprint anti-counterfeiting image corresponds to the area within the boundary of the first detection area 21 on the anti-counterfeiting detection light spot B, which is the effective anti-counterfeiting detection area 23.

[0085] Fig.13 Two-dimensional finger on white background Fig.11 The fingerprint anti-counterfeiting image formed by the photosensitive unit under the irradiation of the anti-counterfeiting detection spot B is shown in FIG. Fig.14 For three-dimensional fingers Fig.11The fingerprint anti-counterfeiting image formed by the photosensitive unit under the irradiation of the anti-counterfeiting detection spot B is shown. Fig.13 and Fig.14 It can be seen that for Fig.11 As shown in the anti-counterfeiting detection spot B, the difference between the fingerprint anti-counterfeiting images of the two-dimensional finger and the three-dimensional finger with a white background in the transition zone is very significant.

[0086] Will Fig.13 and Fig.14 The grayscale curve changes of the fingerprint anti-counterfeiting image are synthesized into a fingerprint anti-counterfeiting image and distributed as follows Fig.15 As shown. Since the reflectivity of the white background of the two-dimensional finger is higher and the reflected light is concentrated in the mirror direction, the grayscale of the fingerprint anti-counterfeiting image of the two-dimensional finger with a white background in the boundary area of ​​the transition zone 53 is significantly higher than the grayscale of the fingerprint anti-counterfeiting image of the three-dimensional finger in the boundary area of ​​the transition zone 53. The grayscale decay rate of the transition zone 53 of the fingerprint anti-counterfeiting image of the two-dimensional finger toward the center of the second imaging area is faster than the grayscale decay rate of the transition zone 53 of the fingerprint anti-counterfeiting image of the three-dimensional finger toward the center of the second imaging area. This phenomenon can be simply explained from an optical point of view as follows: the three-dimensional finger can receive more scattered light and reflected light in a larger angular range in the second imaging area 52, so the grayscale of the second imaging area 52 of the three-dimensional finger anti-counterfeiting image is higher than the grayscale of the second imaging area 52 of the two-dimensional finger with a white background. It can be understood that, Fig.15 A more vivid display of the fingerprint grayscale value Fig.13 , Fig.14 The difference between the two fingerprint anti-counterfeiting images is that the grayscale peak value of the two-dimensional finger with a white background in the transition area 53 is higher than the grayscale value of the three-dimensional finger in the transition area 53, while the grayscale value of the two-dimensional finger with a white background in the second imaging area 52 is lower than the grayscale value of the three-dimensional finger in the second imaging area 52, and in the transition area 53, the slope of the grayscale change of the two-dimensional finger with a white background is larger than the slope of the grayscale change of the three-dimensional finger. Fig.15 In the figure, F represents the grayscale change curve of the fingerprint anti-counterfeiting image corresponding to the three-dimensional finger, and W represents the grayscale change curve of the fingerprint anti-counterfeiting image corresponding to the two-dimensional finger with a white background. Fig.15 In the middle coordinate diagram, the horizontal axis is the image pixel position; the vertical axis is the field grayscale mean.

[0087] Here, Fig.15 Just listed Fig.13 and Fig.14 A method of extracting fingerprint features that differ from two fingerprint anti-counterfeiting images is used to illustrate the use of Fig.11 The anti-counterfeiting detection spot B shown can realize the identification of two-dimensional fingers and three-dimensional fingers, and is not limited to Fig.13 and Fig.14 The two fingerprint anti-counterfeiting images utilize other differential feature extraction methods to achieve the distinction between two-dimensional fingers and three-dimensional fingers.

[0088] Fig.16 For the red two-dimensional finger Fig.11 The fingerprint anti-counterfeiting image formed by the photosensitive unit under the irradiation of the anti-counterfeiting detection spot B is shown in FIG. Fig.17 For three-dimensional fingers Fig.11 The fingerprint anti-counterfeiting image formed by the photosensitive unit under the irradiation of the anti-counterfeiting detection spot B is shown. Fig.16 and Fig.17 It can be seen that for Figure 1 As shown in the anti-counterfeiting detection spot B, the fingerprint anti-counterfeiting image of the two-dimensional finger with a red background is overall dimmer than the fingerprint anti-counterfeiting image of the three-dimensional finger.

[0089] like Fig.18 As shown, Fig.16 and Fig.17 The grayscale distribution of the two fingerprint anti-counterfeiting images is integrated into one graph and compared using a curve. Fig.11 The grayscale change curve of the fingerprint anti-counterfeiting image formed by the photosensitive unit from the center to the edge under the anti-counterfeiting detection spot B of the pattern shown. R represents the grayscale change of the two-dimensional fingerprint with a red background. Fig.11 The grayscale variation curve from the center to the edge of the fingerprint anti-counterfeiting image formed by the photosensitive unit under the irradiation of the anti-counterfeiting detection spot B of the pattern shown. Fig.18 The horizontal axis of the middle coordinate axis is the image pixel position; the vertical axis is the field grayscale average. Since the reflectivity of the two-dimensional finger with a red background is lower, the grayscale of the fingerprint anti-counterfeiting image in the transition area 53 is correspondingly lower than that in the transition area of ​​the three-dimensional finger fingerprint anti-counterfeiting image; the second imaging area 52 in the fingerprint anti-counterfeiting image of the three-dimensional finger can receive more scattered light and reflected light in a larger angular range, so the grayscale of the three-dimensional finger image in the second imaging area 52 is significantly higher than that in the second imaging area 52 of the fingerprint anti-counterfeiting image of the two-dimensional finger with a red background.

[0090] against Fig.15 and Fig.18 The method for extracting the differential parameters from the two-dimensional and three-dimensional fingerprint anti-counterfeiting images shown in the figure can be further calculated by the control unit in the electronic device. Fig.15 and Fig.18 It can be seen that the grayscale value of the 3D finger in the second imaging area is higher than that of the 2D finger in the second imaging area. Although the grayscale value range can also be used to distinguish between 2D and 3D fingers, in order to improve the accuracy of the judgment result, the relative results of multiple point values ​​are used to judge, which can obtain a more reliable judgment result.

[0091] The following describes a Fig.11The specific method of extracting the differential fingerprint characteristic parameters of the two-dimensional finger and the three-dimensional finger in the fingerprint anti-counterfeiting image corresponding to the anti-counterfeiting detection spot B shown. For example, the control unit calculates the grayscale average value of the fingerprint anti-counterfeiting image located in the transition area 53, which is R1; calculates the grayscale average value of the fingerprint anti-counterfeiting image located in the second imaging area 52, which is R2. When R2 / R1 is greater than the anti-counterfeiting determination threshold, it is determined to be a three-dimensional finger. Among them, the anti-counterfeiting determination threshold can be 0.2. When R2 / R1 is greater than the anti-counterfeiting determination threshold, it is determined to be a real finger, otherwise it is determined to be a fake finger.

[0092] Combination Fig.15 and Fig.18 If the ratio of the grayscale average values ​​of the second imaging area 52 and the transition area 53 is used as the judgment condition, it is necessary to ensure that both the peaks and valleys of the grayscale in the fingerprint anti-counterfeiting image exist. Fig.11 In the anti-counterfeiting detection spot B shown in , not all areas of the first detection zone 21 are beneficial to the formation of significantly differentiated areas in the fingerprint anti-counterfeiting image. Therefore, the effective anti-counterfeiting detection area 23 corresponds to the imaging area of ​​the photosensitive unit and is the area actually used by the specific differentiated feature extraction method described above. Under the condition that the optical parameters of the optical lens and the size of the photosensitive unit in the optical fingerprint recognition and anti-counterfeiting device are specific, the radius of the effective anti-counterfeiting detection area 23 corresponding to the main area of ​​effective fingerprint grayscale peak and trough differentiated feature extraction is about 40 pixels. At present Fig.13 , Fig.14 and Fig.16 , Fig.17 The radius of the second detection area 22 set in the image is about 20 pixels. Under the condition that the optical lens parameters are fixed, the area of ​​the effective anti-counterfeiting detection area 23 will be relatively fixed. When the radius of the second detection area 22 is adjusted to change from 15 to 25 pixels, the discrimination between two-dimensional fingers and three-dimensional fingers can still be achieved according to the specific extraction method of the differentiated fingerprint feature parameters described above. Therefore, the area of ​​the second detection area 22 in the effective anti-counterfeiting detection area 23 accounts for about 14% to 40%. This proportion can be adjusted with the changes in the optical parameters in the actual optical fingerprint recognition and anti-counterfeiting device.

[0093] As mentioned above about Fig.11The anti-counterfeiting detection spot B of the pattern shown, in which the first detection area 21 is not entirely helpful for forming the differential feature part in the fingerprint anti-counterfeiting image, and only the effective anti-counterfeiting detection area 23 in the entire pattern is helpful for extracting the differential feature parameters in the fingerprint anti-counterfeiting image. In order to prevent the finger from not accurately pressing the central area of ​​the anti-counterfeiting detection spot B, which affects the anti-counterfeiting judgment result, multiple discrete second detection areas 22 can be set in the anti-counterfeiting detection spot B. The number of the second detection areas 22 can be set and the number of second detection areas 22 can be arranged according to the size of the area of ​​the effective anti-counterfeiting detection area 23 and the size of the anti-counterfeiting detection spot B described above.

[0094] The shapes of the plurality of discrete second detection areas 22 may be the same or different, and the shapes of the plurality of second detection areas 22 may be set as required. The arrangement of the plurality of second detection areas 22 may be relatively flexible. Figures 19 to 21 As shown in the arrangement, a plurality of second detection areas 22 are discretely distributed in the anti-counterfeiting detection light spot B. Fig.19 The plurality of second detection areas 22 shown in the figure are arranged in a rectangular array. Specifically, the plurality of non-luminous pattern units are arranged in an equidistant rectangular array to form an M*N rectangular pattern array. Optionally, M can be selected from 2, 3, 4..., and N can be selected from 2, 3, 4... Or, as Fig. 20 or Fig.21 As shown, a plurality of second detection areas 22 are discretely distributed in the anti-counterfeiting detection spot B in the form of a ring array. Specifically, a plurality of second detection areas 22 are distributed in the form of a circular equidistant. Fig. 20 and Fig.21 The main difference between the anti-counterfeiting detection spot B shown in Fig. 20 The area of ​​the second detection zone 22 located in the center can be smaller than Fig.21 The area of ​​the second detection zone 22 located in the center.

[0095] In use Figures 19 to 21When any anti-counterfeiting detection spot B of any pattern is used for anti-counterfeiting detection, multiple second imaging areas 52 and transition areas surrounding the second imaging areas 52 will also be formed on the photosensitive unit. Taking the method of judging whether the target finger is a two-dimensional finger or a three-dimensional finger by the ratio of the average value of the grayscale of the second imaging area 52 to the average value of the transition area being greater than the anti-counterfeiting judgment threshold as an example, the judgment results corresponding to each second imaging area 52 in the N groups are obtained respectively, where the judgment result of the M group is that the target object is a three-dimensional real finger, and at the same time, when the ratio of M / N is greater than the anti-counterfeiting judgment ratio, the detected target finger can be judged to be a three-dimensional real finger. Among them, the anti-counterfeiting judgment ratio can be 40%. This anti-counterfeiting judgment ratio can be set specifically according to the number of second detection areas 22 in the anti-counterfeiting detection spot B, and the number of second detection areas 22 that can be covered by the finger and other conditions.

[0096] The above examples Figures 19 to 21 These are just some typical patterns of anti-counterfeiting detection spots B of multiple second detection areas 22, where the shape of the second detection area 22 is the same as that of Fig.11 The circular second detection area 22 listed is for illustration only and does not constitute a restrictive interpretation of the protection scope of the present application.

[0097] In other embodiments, the first detection area 21 in the pattern of the anti-counterfeiting detection light spot B may be a dark area, and the second detection area 22 may be a bright area. Fig.11 The luminous intensity of the first detection area 21 and the second detection area 22 in the anti-counterfeiting detection light spot B with a relatively large proportion of bright areas can be interchanged. When the target fingerprint irradiated by the anti-counterfeiting detection light spot B with a large difference in brightness passes through the optical lens, a transition area between light and dark will be formed on the photosensitive unit. The imaging of the two-dimensional finger and the three-dimensional finger in this transition area will be more obvious. The control unit can distinguish the two-dimensional finger and the three-dimensional finger by extracting these differences.

[0098] The extraction of differential feature parameters in the fingerprint anti-counterfeiting images corresponding to two-dimensional fingers and three-dimensional fingers is not limited to the methods listed above. The differential feature parameters of the two fingerprint anti-counterfeiting images can be extracted from the perspective of fingerprints, such as the grayscale of the fingerprint collected in a specific area, or the grayscale ratio; however, differential features can also be extracted from the perspective of images. The difference in image grayscale distribution of different areas of the fingerprint anti-counterfeiting images formed by the two-dimensional finger and the three-dimensional finger under the detection of the anti-counterfeiting detection light spot of the preset pattern can also be used to distinguish the two-dimensional finger and the three-dimensional finger. Since there are many different ways to extract differential feature parameters, there are also many different ways to implement them from the image processing method, which cannot be exhaustively listed here.

[0099] From the pattern of the anti-counterfeiting detection spot B provided above, by extracting the differentiated features in the fingerprint anti-counterfeiting image formed on the photosensitive unit, the discrimination between two-dimensional fingers and three-dimensional real fingers can be achieved. For the fingerprint anti-counterfeiting image formed on the photosensitive unit corresponding to the anti-counterfeiting detection spot B, the fingerprint features with differences in the transition zone of the fingerprint anti-counterfeiting image can be extracted to achieve the discrimination between two-dimensional and three-dimensional fingers, or the differentiated fingerprint features with different distributions in the transition zone 53 and the second imaging zone 52 in the fingerprint anti-counterfeiting image can be extracted for discrimination. In short, the specific method of extracting differentiated fingerprints can be selected according to the configuration of the actual electronic device control unit. The premise is that the pattern of this anti-counterfeiting detection spot B is relatively different for the fingerprint anti-counterfeiting images formed on the photosensitive unit for two-dimensional fingers and three-dimensional fingers.

[0100] After many experiments and comparisons, it was found that the first detection area 21 and the second detection area 22 with different brightness levels were set on the anti-counterfeiting detection spot B. Since the real three-dimensional finger and the two-dimensional finger have large differences in reflectivity, reflected light and other parameters during the imaging process, the fingerprint anti-counterfeiting image obtained by the photosensitive unit will also be different, especially in the fingerprint anti-counterfeiting image. The transition area at the junction of light and dark is more obvious. For the anti-counterfeiting detection spot B with a large proportion of dark areas, in order to make the fingerprint anti-counterfeiting image have a more obvious difference for the two-dimensional finger and the three-dimensional finger, the proportion of dark areas and bright areas is within a certain threshold range, and the difference between the fingerprint anti-counterfeiting images corresponding to the three-dimensional real finger and the two-dimensional fake finger is more obvious. However, as described above, due to the large proportion of dark areas in the anti-counterfeiting detection spot B, the photosensitive unit needs a relatively longer time to form the fingerprint anti-counterfeiting image, which easily leads to a slightly longer time for the entire optical fingerprint recognition and anti-counterfeiting. If this disadvantage can be compensated by the configuration of the control unit, the application of this problem caused by the large proportion of dark areas in the anti-counterfeiting detection spot B in the electronic device terminal will not affect the user's experience of using the optical fingerprint recognition and anti-counterfeiting system in the electronic device. At the same time, the above content also illustrates the pattern of the anti-counterfeiting detection spot B with a relatively large bright area and the extraction of anti-counterfeiting features. This type of embodiment has a more obvious advantage than the anti-counterfeiting detection spot B with a relatively large dark area in that it can save the exposure time required for the photosensitive unit to form the fingerprint anti-counterfeiting image, that is, it can shorten the time required for the optical fingerprint anti-counterfeiting stage.

[0101] The anti-counterfeiting detection spot B of the preset pattern formed by two detection areas with different brightness described above illuminates the target fingerprint, and the optical lens of the optical recognition and anti-counterfeiting device processes the light signal reflected by the target fingerprint. The photosensitive unit arranged under the optical lens can form a fingerprint anti-counterfeiting image. The subsequent control unit can process this fingerprint anti-counterfeiting image according to the extraction method of the preset differential feature parameters to determine whether the target fingerprint is a two-dimensional finger or a three-dimensional real finger. The specific differential feature extraction method has been illustrated in the above content and cannot be exhaustive, so it will not be repeated here.

[0102] It should be understood that although the above content only uses the OLED screen as an example to illustrate the formation of the anti-counterfeiting detection spot B, for non-self-luminous display screens, a built-in light source or an external light source can be used to guide the light path so that the detection light is irradiated to the surface of the pressed object. The subsequent identification and anti-counterfeiting methods are roughly the same as the above-described embodiments, so they will not be repeated.

[0103] The following describes an optical fingerprint recognition and anti-counterfeiting system formed by applying the optical fingerprint recognition and anti-counterfeiting method introduced above to an electronic device.

[0104] Combination Fig. 22 For explanation, the optical fingerprint recognition and anti-counterfeiting system includes: an optical recognition and anti-counterfeiting device and a control unit 6. The optical recognition and anti-counterfeiting device includes a detection light source 20, an optical functional unit 30 and a photosensitive unit 50. The detection light source 20 irradiates the object to be identified on the fingerprint recognition area of ​​the electronic device. If the detection light source is realized by a self-luminous display screen of the electronic device, the detection light source is arranged in the display screen, that is, the detection light source is composed of luminous pixels in the display screen. The optical functional unit 30 is arranged below the fingerprint recognition area to receive the light signal reflected by the object to be identified. The optical functional unit is an optical processing component mainly composed of an optical lens. The photosensitive unit 50 is arranged below the optical functional unit to receive the light signal processed by the optical functional unit to form a fingerprint sensing image.

[0105] Among them, the control unit 6 controls the detection light source 20 to serve as an identification light source and an anti-counterfeiting light source respectively. When the electronic device performs fingerprint identification and anti-counterfeiting on the identification object, the system controls the detection light source 20 to form an anti-counterfeiting detection spot B of a preset pattern. The preset pattern of the anti-counterfeiting detection spot B includes a first detection area and a second detection area with different luminous intensities; the control unit 6 extracts the anti-counterfeiting feature parameters in the fingerprint sensing image output by the photosensitive unit 50 corresponding to the anti-counterfeiting detection spot B to determine whether the object to be identified is a two-dimensional image or a three-dimensional image. When the electronic device performs fingerprint identification on the identification object, the system controls the detection light source 20 to form an identification spot to illuminate the target fingerprint on the fingerprint identification area, extract the fingerprint identification feature of the target fingerprint, and match the extracted fingerprint identification feature with the fingerprint identification feature pre-stored by the control unit to determine whether the extracted fingerprint identification feature matches the stored fingerprint identification feature. Fingerprint identification and fingerprint anti-counterfeiting are two independent processes, and the order of fingerprint identification and anti-counterfeiting can be set according to the specific application scenario.

[0106] When the system performs fingerprint anti-counterfeiting detection, the fingerprint sensing image output by the photosensitive unit 50 corresponding to the anti-counterfeiting detection spot B includes a first imaging area corresponding to the first detection area, a transition area adjacent to the first imaging area, and a second imaging area corresponding to the second detection area; the transition area is located between the first imaging area and the second imaging area. Among them, the luminous intensity of the first detection area is greater than the luminous intensity of the second detection area, and the luminous intensity of the second detection area is zero, which facilitates the control and implementation of the anti-counterfeiting detection spot B of the preset pattern. Through multiple groups of different anti-counterfeiting detection spots B, it is found that when a certain proportion of anti-counterfeiting detection spots B with light and dark patterns appear, the two-dimensional finger and three-dimensional finger fingerprint anti-counterfeiting images formed by the photosensitive unit 50 for the same anti-counterfeiting detection spot B pattern may have relatively obvious differences. By extracting these regular differentiation features through the control unit 6, it can be realized whether the target object is a two-dimensional finger or a three-dimensional finger.

[0107] It should be noted that, in the description of this application, the terms "first", "second", etc. are only used for descriptive purposes and to distinguish similar objects. There is no order of precedence between the two, and they cannot be understood as indicating or implying relative importance. In addition, in the description of this application, unless otherwise specified, the meaning of "plurality" is two or more.

[0108] The above-mentioned various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referenced to each other. Each embodiment focuses on the differences from other embodiments.

[0109] The above are only a few embodiments of the present invention. Although the embodiments disclosed by the present invention are as above, the contents are only embodiments adopted for facilitating the understanding of the present invention and are not used to limit the present invention. Any technician in the technical field to which the present invention belongs can make any modification and change in the form and details of the embodiments without departing from the spirit and scope disclosed by the present invention, but the patent protection scope of the present invention shall still be subject to the scope defined by the attached claims.

Claims

1. An optical fingerprint recognition and anti-counterfeiting method, characterized in that: include: forming a fingerprint recognition light spot, and irradiating a target object with the fingerprint recognition light spot; Forming an anti-counterfeiting detection light spot having a preset pattern, and irradiating a target object with the anti-counterfeiting detection light spot; Providing a photosensitive unit, respectively receiving the fingerprint information carried by the target object under the illumination of the fingerprint recognition light spot and the anti-counterfeiting detection light spot, the fingerprint information carried by the target object under the illumination of the anti-counterfeiting detection light spot received by the photosensitive unit forms a fingerprint anti-counterfeiting image; Determine whether the target object is a two-dimensional finger or a three-dimensional finger according to the fingerprint anti-counterfeiting image; wherein the preset pattern of the anti-counterfeiting detection light spot includes a first detection area and a second detection area with different luminous intensities; extract the differential feature parameters corresponding to the two-dimensional finger and the three-dimensional finger in the fingerprint anti-counterfeiting image to determine whether the target object is a two-dimensional finger or a three-dimensional finger; The fingerprint anti-counterfeiting image includes a first imaging area corresponding to the first detection area, a transition area adjacent to the first imaging area, and a second imaging area corresponding to the second detection area; the transition area is located between the first imaging area and the second imaging area; The step of extracting the differential feature parameters corresponding to the two-dimensional finger and the three-dimensional finger in the fingerprint anti-counterfeiting image to determine whether the target object is a two-dimensional finger or a three-dimensional hand includes: Extract fingerprint features with differences in the transition zone in the fingerprint anti-counterfeiting image to achieve the identification of two-dimensional and three-dimensional fingers, or extract differentiated fingerprint features with different distributions in the transition zone and the second imaging zone in the fingerprint anti-counterfeiting image for identification.

2. The optical fingerprint recognition and anti-counterfeiting method according to claim 1, characterized in that: The luminescence intensity of the first detection zone is greater than the luminescence intensity of the second detection zone, and the luminescence intensity of the second detection zone is zero.

3. The optical fingerprint recognition and anti-counterfeiting method according to claim 2, characterized in that: The area of ​​the first detection zone is larger than the area of ​​the second detection zone.

4. The optical fingerprint recognition and anti-counterfeiting method according to claim 1, characterized in that: The second detection areas are discretely distributed in the anti-counterfeiting detection light spot.

5. The optical fingerprint recognition and anti-counterfeiting method according to claim 1, characterized in that: The differential feature parameter includes: a grayscale value or a contrast ratio of a grayscale value of a fingerprint image in an anti-counterfeiting area corresponding to an anti-counterfeiting detection light spot of a preset pattern in the fingerprint anti-counterfeiting image.

6. The optical fingerprint recognition and anti-counterfeiting method according to claim 5, characterized in that: The method also includes setting a threshold range for the differential feature parameter, and determining whether the target object is a two-dimensional finger or a three-dimensional finger based on whether the differential feature parameter is within the threshold range.

7. The optical fingerprint recognition and anti-counterfeiting method according to claim 1, characterized in that: The anti-counterfeiting detection light spot of the preset pattern includes a plurality of discrete second detection areas.

8. An optical fingerprint recognition and anti-counterfeiting system, applied to an electronic device with a fingerprint recognition area, characterized in that: include: Optical identification and anti-counterfeiting devices and control units; The optical recognition and anti-counterfeiting device comprises: A detection light source, the detection light source irradiates the object to be identified on the fingerprint identification area of ​​the electronic device; An optical functional unit, disposed below the fingerprint recognition area, receiving a light signal reflected by the object to be recognized; and A photosensitive unit, disposed below the optical functional unit, receiving the optical signal processed by the optical functional unit to form a fingerprint sensing image; Wherein, the control unit controls the detection light source to serve as an identification light source and an anti-counterfeiting light source respectively; when the electronic device performs fingerprint identification and anti-counterfeiting on the identification object, the system controls the detection light source to form an anti-counterfeiting detection light spot of a preset pattern; the preset pattern of the anti-counterfeiting detection light spot includes a first detection area and a second detection area with different luminous intensities; the control unit extracts the anti-counterfeiting feature parameters in the fingerprint sensing image output by the photosensitive unit corresponding to the anti-counterfeiting detection light spot to determine whether the object to be identified is a two-dimensional image or a three-dimensional image, The fingerprint sensing image output by the photosensitive unit corresponding to the anti-counterfeiting detection light spot includes a first imaging area corresponding to the first detection area, a transition area adjacent to the first imaging area, and a second imaging area corresponding to the second detection area; the transition area is located between the first imaging area and the second imaging area; The control unit extracts anti-counterfeiting feature parameters in the fingerprint sensing image output by the photosensitive unit corresponding to the anti-counterfeiting detection light spot to determine whether the object to be identified is a two-dimensional image or a three-dimensional image, including: Extract fingerprint features with differences in the transition zone in the fingerprint anti-counterfeiting image to achieve the identification of two-dimensional and three-dimensional fingers, or extract differentiated fingerprint features with different distributions in the transition zone and the second imaging zone in the fingerprint anti-counterfeiting image for identification.

9. The optical fingerprint recognition and anti-counterfeiting system according to claim 8, characterized in that: The luminescence intensity of the first detection zone is greater than the luminescence intensity of the second detection zone, and the luminescence intensity of the second detection zone is zero.

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