Fingerprint imaging module, fingerprint acquisition method thereof and electronic device

Abstract

A fingerprint imaging module, a fingerprint acquisition method thereof, and an electronic device. The fingerprint imaging module includes: a first contact surface and a second contact surface, the first contact surface and the second contact surface are arranged at intervals facing away from each other and are both adapted to contact a fingerprint; a point light source component and a sensing component, the point light source component and the sensing component are located between the first contact surface and the second contact surface, and the photosensitive surface of the sensing component faces the second contact surface; the incident light generated by the point light source component is reflected on the first contact surface and the second contact surface successively, and then is received by the photosensitive surface of the sensing component to obtain a fingerprint image. The technical solution of the present invention can obtain fingerprint images on both sides, and the fingerprint imaging module has a wider application range.

Description

Technical Field

[0001] The present invention relates to the field of fingerprint imaging, and particularly to a fingerprint imaging module, a fingerprint acquisition method thereof, and an electronic device. Background Art

[0002] The existing fingerprint recognition technology collects a fingerprint image of a human body through an image acquisition device, and then compares it with the existing fingerprint imaging information in the fingerprint recognition system to achieve identity recognition. Due to the convenience of using fingerprint recognition technology and the uniqueness of human fingerprints, fingerprint recognition technology has been widely applied in various fields, such as security inspection fields like public security bureaus and customs, building access control systems, and consumer fields such as personal computers and mobile phones, etc.

[0003] Fingerprint modules are increasingly applied in mobile devices such as laptop computers, tablet computers, and mobile phones, enabling related mobile devices to achieve automatic unlocking and functions. In particular, fingerprint recognition in mobile phones is widely used.

[0004] The existing fingerprint imaging module only has one photosensitive surface and can only obtain a fingerprint image from one side of the module, thus limiting the applicable range of the fingerprint module. Summary of the Invention

[0005] The problem solved by the present invention is to provide a fingerprint imaging module, a fingerprint acquisition method thereof, and an electronic device to achieve the acquisition of double-sided fingerprint images.

[0006] To solve the above problems, the present invention provides a fingerprint imaging module, including:

[0007] A first contact surface and a second contact surface, the first contact surface and the second contact surface are arranged at intervals facing away from each other and are both adapted to contact a fingerprint; a point light source assembly and a sensing assembly, the point light source assembly and the sensing assembly are located between the first contact surface and the second contact surface, and the photosensitive surface of the sensing assembly faces the second contact surface; the incident light generated by the point light source assembly is reflected successively on the first contact surface and the second contact surface and then received by the photosensitive surface of the sensing assembly to obtain a fingerprint image.

[0008] Optionally, it further includes: a light-transmitting cover plate, and the light-transmitting cover plate is located on the side of the point light source assembly facing the first contact surface.

[0009] Optionally, the first contact surface is the surface of the light-transmitting cover plate facing away from the point light source assembly.

[0010] Optionally, the second contact surface is the surface of the sensing assembly facing away from the point light source assembly.

[0011] Optionally, the sensing component includes: a light-transmitting layer having a first surface and a second surface facing away from each other; a photosensitive layer located on the first surface of the light-transmitting layer; and the second contact surface is the second surface of the light-transmitting layer.

[0012] Optionally, the photosensitive layer includes: a substrate and photosensitive pixels located on the substrate, and the photosensitive pixels are located between the substrate and the light-transmitting layer.

[0013] Optionally, the sensing component further includes: a mask layer located on a side of the photosensitive pixels facing the first contact surface.

[0014] Optionally, the fingerprint imaging module is adapted to obtain a first fingerprint image of a fingerprint located on the first contact surface or a second fingerprint image of a fingerprint located on the second contact surface.

[0015] Optionally, the fingerprint imaging module is adapted to simultaneously obtain a first fingerprint image of a fingerprint located on the first contact surface and a second fingerprint image of a fingerprint located on the second contact surface.

[0016] Optionally, the first fingerprint image is obtained by the sensing component collecting light rays that are reflected successively on the first contact surface and the second contact surface by the incident light generated by the point light source component, and the second fingerprint image is obtained by the sensing component collecting light rays that are reflected successively on the first contact surface and the second contact surface by the incident light generated by the point light source component, and / or light rays scattered by a fingerprint located on the second contact surface.

[0017] Optionally, the light rays scattered by a fingerprint located on the second contact surface include: ambient light scattered by a fingerprint located on the second contact surface.

[0018] Optionally, the first fingerprint image is obtained by the sensing component collecting light rays that are reflected successively on the first contact surface and the second contact surface by the incident light generated by the point light source component, and the second fingerprint image is obtained by the sensing component collecting light rays that are reflected successively on the first contact surface and the second contact surface by the incident light generated by the point light source component, and light rays scattered by a fingerprint located on the second contact surface.

[0019] Optionally, the light rays scattered by a fingerprint located on the second contact surface include: light rays of the point light source component scattered by a fingerprint located on the second contact surface, and ambient light scattered by a fingerprint located on the second contact surface.

[0020] Optionally, the fingerprint imaging module simultaneously obtains a superimposed image of the first fingerprint image and the second fingerprint image. The fingerprint imaging module further includes: a processor, and the processor is adapted to separate the first fingerprint image and the second fingerprint image based on the superimposed image.

[0021] Optionally, the processor is adapted to separate the first fingerprint image and the second fingerprint image according to the different magnification ratios of the first fingerprint image and the second fingerprint image.

[0022] Optionally, the point light source assembly includes: a plurality of point light sources arranged in an array.

[0023] Optionally, the point light source assembly includes at least one of a liquid crystal display screen, an active matrix organic light emitting diode display screen, or a light emitting diode display screen.

[0024] Optionally, the point light source assembly includes an LED lamp.

[0025] In addition, the present invention further provides an electronic device, including: the fingerprint imaging module of the present invention.

[0026] Correspondingly, the present invention further provides a fingerprint acquisition method using the fingerprint imaging module of the present invention, which specifically includes: generating incident light, and the incident light is reflected successively on the first contact surface and the second contact surface; receiving the reflected light to obtain a fingerprint image.

[0027] Optionally, when there is a fingerprint contact on the first contact surface, in the step of obtaining a fingerprint image, receiving the reflected light to obtain a first fingerprint image of the fingerprint located on the first contact surface; when there is a fingerprint contact on the second contact surface, in the step of obtaining a fingerprint image, receiving the reflected light to obtain a second fingerprint image of the fingerprint located on the second contact surface.

[0028] Optionally, when there is a fingerprint contact on both the first contact surface and the second contact surface, in the step of obtaining a fingerprint image, receiving the reflected light to obtain a first fingerprint image and a second fingerprint image.

[0029] Optionally, the step of obtaining the first fingerprint image includes: collecting the light reflected successively by the incident light on the first contact surface and the second contact surface to obtain the first fingerprint image; the step of obtaining the second fingerprint image includes: collecting the light reflected successively by the incident light on the first contact surface and the second contact surface, and / or the light scattered by the fingerprint located on the second contact surface, to obtain the second fingerprint image.

[0030] Optionally, the light scattered by the fingerprint on the second contact surface includes: ambient light scattered by the fingerprint on the second contact surface.

[0031] Optionally, the first fingerprint image is obtained by the sensing component collecting the light reflected successively on the first contact surface and the second contact surface by the incident light generated by the point light source component, and the second fingerprint image is obtained by the sensing component collecting the light reflected successively on the first contact surface and the second contact surface by the incident light generated by the point light source component, and the light scattered by the fingerprint on the second contact surface.

[0032] Optionally, the light scattered by the fingerprint on the second contact surface includes: the light of the point light source component scattered by the fingerprint on the second contact surface, and the ambient light scattered by the fingerprint on the second contact surface.

[0033] Optionally, the step of obtaining the fingerprint image further includes: obtaining a superimposed image of the first fingerprint image and the second fingerprint image at the same time; separating the first fingerprint image and the second fingerprint image based on the superimposed image.

[0034] Optionally, the step of separating the first fingerprint image and the second fingerprint image includes: separating the first fingerprint image and the second fingerprint image according to the different magnification ratios of the first fingerprint image and the second fingerprint image.

[0035] Compared with the prior art, the technical solution of the present invention has the following advantages:

[0036] In the technical solution of the present invention, the fingerprint imaging module has a first contact surface and a second contact surface that can both input fingerprint information. The point light source component and the sensing component are located between the first contact surface and the second contact surface, and the photosensitive surface of the sensing component faces the second contact surface; the incident light generated by the point light source component is reflected successively on the first contact surface and the second contact surface, and then received by the photosensitive surface of the sensing component to obtain a fingerprint image. The fingerprint imaging module can obtain fingerprint images on both sides, and the fingerprint imaging module has a wider application range. Description of the Drawings

[0037] Figure 1 is a schematic cross-sectional structure diagram of an embodiment of the fingerprint imaging module of the present invention;

[0038] Figure 2 is Figure 1 a schematic optical path diagram of the fingerprint imaging module shown obtaining the first fingerprint image;

[0039] Figure 3 is Figure 1Schematic optical path diagram of the fingerprint imaging module for obtaining a second fingerprint image;

[0040] Figure 4 is Figure 1 Schematic optical path diagram of the fingerprint imaging module for simultaneously obtaining a first fingerprint image and a second fingerprint image;

[0041] Figure 5 is Figure 1 Equivalent optical path diagram of the sensing component in the fingerprint imaging module for simultaneously obtaining the first fingerprint image and the second fingerprint image;

[0042] Figure 6 Schematic structural diagram of an embodiment of the electronic device of the present invention;

[0043] Figure 7 is Figure 6 Schematic cross-sectional structure diagram along the dotted line A2 in the embodiment of the electronic device;

[0044] Figure 8 Schematic structural diagram of another embodiment of the electronic device of the present invention;

[0045] Figure 9 is Figure 8 Schematic cross-sectional structure diagram along the dotted line B2 in the embodiment of the electronic device;

[0046] Figure 10 Schematic flow diagram of an embodiment of the fingerprint acquisition method of the present invention. Detailed implementation manners

[0047] As can be seen from the background art, in the prior art, the fingerprint imaging module can only perform fingerprint imaging on one side.

[0048] To solve the above technical problems, the present invention provides a fingerprint imaging module, including:

[0049] A first contact surface and a second contact surface, the first contact surface and the second contact surface are spaced apart from each other and are both adapted to contact a fingerprint; a point light source component and a sensing component, the point light source component and the sensing component are located between the first contact surface and the second contact surface, and the light-sensitive surface of the sensing component faces the second contact surface; the incident light generated by the point light source component is reflected on the first contact surface and the second contact surface in sequence and then received by the light-sensitive surface of the sensing component to obtain a fingerprint image. The technical solution of the present invention can obtain fingerprint images on both sides, and the fingerprint imaging module has a wider range of applications.

[0050] To make the above objects, features and advantages of the present invention more obvious and understandable, the following detailed description of the specific embodiments of the present invention will be given with reference to the accompanying drawings.

[0051] Refer toFigures 1 to 3 , showing a schematic structural diagram of an embodiment of the fingerprint imaging module of the present invention; wherein Figure 1 is a schematic cross-sectional structure diagram of an embodiment of the fingerprint imaging module of the present invention; Figure 2 is Figure 1 a schematic optical path diagram of the fingerprint imaging module shown obtaining a first fingerprint image; Figure 3 is Figure 1 a schematic optical path diagram of the fingerprint imaging module shown obtaining a second fingerprint image.

[0052] The fingerprint imaging module includes:

[0053] A first contact surface 110 and a second contact surface 120, the first contact surface 110 and the second contact surface 120 are arranged at intervals back to back and are both suitable for contacting fingerprints; a point light source assembly 130 and a sensing assembly 140, the point light source assembly 130 and the sensing assembly 140 are located between the first contact surface 110 and the second contact surface 120, and the photosensitive surface 141 of the sensing assembly 140 faces the second contact surface 120; the incident light generated by the point light source assembly 130 is reflected successively on the first contact surface 110 and the second contact surface 120, and then is received by the photosensitive surface 141 of the sensing assembly 140 to obtain a fingerprint image.

[0054] The sensing assembly 140 and the point light source assembly 130 are located between the first contact surface 110 and the second contact surface 120, so the fingerprint imaging module can obtain fingerprint images from both sides, and the fingerprint imaging module has a wider application range.

[0055] The first contact surface 110 and the second contact surface 120 are respectively used to input fingerprint information, that is, both the first contact surface 110 and the second contact surface 120 can be touched by a finger to input fingerprint information.

[0056] In some embodiments of the present invention, the fingerprint imaging module further includes: a light-transmitting cover plate 111, and the light-transmitting cover plate 111 is located on the side of the point light source assembly 130 facing the first contact surface 110. As Figure 1 shown, in this embodiment, the first contact surface 110 is the surface of the light-transmitting cover plate 110 facing away from the point light source assembly 130.

[0057] In addition, in some embodiments of the present invention, the second contact surface 120 is the surface of the sensing assembly 140 facing away from the point light source assembly 130. As Figure 1As shown, the sensing component 140 includes: a light-transmitting layer 142 having opposite first and second surfaces; a photosensitive layer 143 located on the first surface of the light-transmitting layer 142; and the second contact surface 120 is the second surface of the light-transmitting layer 142.

[0058] In some embodiments of the present invention, the photosensitive layer 143 includes: a substrate 143a and photosensitive pixels 143b located on the substrate 143a, and the photosensitive pixels 143b are located between the substrate 143a and the light-transmitting layer 142.

[0059] In addition, in some embodiments of the present invention, the photosensitive pixel 143b has opposite first and second surfaces. The first surface faces the first contact surface 110, and the second surface faces the second contact surface 120. Both the first surface and the second surface are light-transmitting so that light can enter the photosensitive pixel 143b from the first surface or the second surface. The sensing component 140 further includes: a mask layer 143c located on the side of the photosensitive pixel 143b facing the first contact surface 110.

[0060] Specifically, as Figure 1 shown, the mask layer 143c includes a plurality of discrete light-blocking portions. Each light-blocking portion covers the first surface of the photosensitive pixel 143b. The lateral dimension (i.e., the direction parallel to the first contact surface 110) of the light-blocking portion is greater than or equal to the lateral dimension of the photosensitive pixel 143b. A light-transmitting medium is filled between adjacent light-blocking portions, so that signal light can enter the light-transmitting layer 142 through the light-transmitting medium between adjacent light-blocking portions and between adjacent photosensitive pixels 143b. The light-blocking portions of the mask layer 143c are made of light-impermeable materials. Therefore, the mask layer 143c can effectively prevent light from being incident from the first surface of the photosensitive pixel 143b and being received. In the embodiments of the present invention, the photosensitive surface 141, that is, the second surface of the photosensitive pixel 143b, faces away from the first contact surface 110, which can effectively avoid the interference of stray light such as ambient light, because it is difficult for ambient light to undergo total internal reflection on the second surface of the light-transmitting layer 142 and be received by the photosensitive surface 141. Moreover, the setting of the mask layer 143c can further reduce the influence of stray light. Therefore, the setting of the photosensitive surface 141 facing away and the mask layer 143c can effectively improve the signal-to-noise ratio when the first contact surface 110 is a light-transmitting surface, that is, when ambient light can transmit through all the material film layers between the first contact surface 110 and the photosensitive pixel 143b.

[0061] In some embodiments, the mask layer 143c is located on the side of the substrate 143a close to the photosensitive pixel 143b, that is, between the substrate 143a and the photosensitive pixel 143b; in other embodiments, the mask layer 143c is located on the side of the substrate 143a away from the photosensitive pixel 143b, that is, between the substrate 143a and the point light source assembly 130.

[0062] In some embodiments, the sensing assembly 140 further includes an electrode, and the electrode can serve as a light-shielding portion of the mask layer 143c to block light from entering the photosensitive pixel 143b from the first surface thereof and being received by the photosensitive pixel 143b. The electrode can be a metal electrode, and the lateral dimension of the electrode is greater than or equal to the lateral dimension of the photosensitive pixel 143b.

[0063] In some embodiments of the present invention, the point light source assembly 130 includes a plurality of point light sources, and the plurality of point light sources are arranged in an array. Specifically, in this embodiment, the point light source assembly 130 is an active matrix organic light emitting diode (AMOLED) display screen, and the point light source is a display pixel of the active matrix organic light emitting diode display screen. In other embodiments of the present invention, the point light source assembly can also be a liquid crystal display screen or a light emitting diode display screen, such as a micro light emitting diode display (Mirco-LED) and a quantum dot light emitting diode display (Q-LED).

[0064] In other embodiments, the point light source assembly 130 includes an LED lamp, that is, the number of the LED lamps is at least one.

[0065] In some embodiments of the present invention, the fingerprint imaging module is adapted to obtain a first fingerprint image of a fingerprint located on the first contact surface or a second fingerprint image of a fingerprint located on the second contact surface. Specifically, when a fingerprint touches the first contact surface, the fingerprint imaging module is adapted to obtain a first fingerprint image of the fingerprint located on the first contact surface; when a fingerprint touches the second contact surface, the fingerprint imaging module is adapted to obtain a second fingerprint image of the fingerprint located on the second contact surface. That is, the fingerprint imaging module is adapted to perform unilateral fingerprint image recognition.

[0066] Wherein, the first fingerprint image is obtained by the sensing assembly 140 collecting the light rays that are reflected successively on the first contact surface 110 and the second contact surface 120 by the incident light generated by the point light source assembly 130.

[0067] Specifically, as Figure 2As shown, the point light source in the point light source assembly 130 generates incident light 151. The incident light 151 is projected onto the first contact surface 110 and undergoes total internal reflection, and is modulated by the fingerprint information input on the first contact surface 110 to form waveguide light 151a carrying the fingerprint information on the first contact surface 110; the waveguide light 151a successively transmits through the point light source assembly 130 and the sensing assembly 140 and is projected onto the second contact surface 120; the waveguide light 151a undergoes total internal reflection again on the second contact surface 120 and is then received by the photosensitive surface 141 (such as Figure 1 shown) of the sensing assembly 140 to obtain a first fingerprint image.

[0068] The second fingerprint image is obtained by the sensing assembly 140 collecting the light reflected successively by the incident light generated by the point light source assembly 130 on the first contact surface 110 and the second contact surface 120, and the light scattered by the fingerprint located on the second contact surface 120.

[0069] As Figure 3 shown, on the one hand, the point light source in the point light source assembly 130 generates incident light 152, which is projected onto the second contact surface 120 after total internal reflection by the first contact surface 110, and is modulated by the fingerprint information input on the second contact surface 120 to form waveguide light 152b carrying the fingerprint information on the second contact surface 120; the waveguide light 152b is received by the sensing assembly 140. On the other hand, the sensing assembly 140 also receives the light scattered by the fingerprint on the second contact surface 120 (as shown by the dotted line in Figure 3 ), and the light scattered by the fingerprint on the second contact surface 120 includes ambient light. Specifically, the ambient light on the side of the first contact surface 110 away from the sensing assembly successively transmits through the first contact surface 110 and the second contact surface 120, is projected onto the fingerprint on the second contact surface 120, is scattered by the fingerprint on the second contact surface 120 and then returns, and is thus received by the sensing assembly 140.

[0070] In some embodiments of the present invention, the fingerprint imaging module is adapted to simultaneously obtain a first fingerprint image of the fingerprint located on the first contact surface and a second fingerprint image of the fingerprint located on the second contact surface, that is, when there are fingerprints in contact on both the first contact surface 110 and the second contact surface 120, and the sensing assembly 140 simultaneously collects the light reflected successively by the incident light generated by the point light source assembly on the first contact surface and the second contact surface and the light scattered by the fingerprint located on the second contact surface. As Figure 4As shown, the point light source in the point light source assembly 130 generates incident light 153. The incident light 153 is projected onto the first contact surface 110 and undergoes total internal reflection, and is modulated by the fingerprint information input on the first contact surface 110 to form waveguide light 153a carrying the fingerprint information on the first contact surface 110; the waveguide light 153a successively transmits through the point light source assembly 130 and the sensing assembly 140, is projected onto the second contact surface 120 and is modulated by the fingerprint information input on the second contact surface 120 to form waveguide light 153b carrying the fingerprint information on the second contact surface 120; the waveguide light 153b is received by the sensing assembly 140.

[0071] On the other hand, the sensing assembly 140 also receives the light scattered by the fingerprint on the second contact surface 120 (as shown by the dotted line in Figure 3 ), and the light scattered by the fingerprint on the second contact surface 120 includes: the light originating from the point light source assembly 130 and the ambient light originating from the outside.

[0072] Specifically, the point light source in the point light source assembly 130 generates incident light 153 that transmits through the first contact surface 110 and is projected onto the fingerprint on the first contact surface 110, and is scattered by the fingerprint on the first contact surface 110 and then returns; the returned light successively transmits through the first contact surface 110 and the second contact surface 120 and is projected onto the fingerprint on the second contact surface 120, and is scattered by the fingerprint on the second contact surface 120 and returns again, thus being received by the sensing assembly 140. And the ambient light outside the first contact surface 110 on the side away from the sensing assembly successively transmits through the first contact surface 110 and the second contact surface 120, is projected onto the fingerprint on the second contact surface 120, and is scattered by the fingerprint on the second contact surface 120 and returns, thus being received by the sensing assembly 140.

[0073] It should be noted that Figure 2 、 Figure 3 and Figure 4 respectively show the optical path diagrams of the sensing assembly 140 obtaining the first fingerprint image, obtaining the second fingerprint image, and simultaneously obtaining the first fingerprint image and the second fingerprint image. Among them, Figure 2 、 Figure 3 and Figure 4 omit some details of the point light source assembly 130 and the sensing assembly 140 to clearly show the optical path, and the detailed structures of the point light source assembly 130 and the sensing assembly 140 can be referred to Figure 1 .

[0074] For Figure 4In the illustrated embodiment, the fingerprint imaging module further includes: a processor (not shown in the figure), and the processor is adapted to separate the first fingerprint image and the second fingerprint image.

[0075] With reference to Figure 5 , there is shown Figure 1 an equivalent optical path diagram of the sensing component 140 in the illustrated fingerprint imaging module simultaneously obtaining the first fingerprint image and the second fingerprint image.

[0076] Since the first fingerprint image is obtained by receiving waveguide light, and the incident angle of the waveguide light is relatively large (greater than the total reflection critical angle), the obtained first fingerprint image has a relatively large magnification ratio compared with the fingerprint information input on the first contact surface 110; while the second fingerprint image is obtained by receiving waveguide light and the light scattered by the fingerprint on the second contact surface 120. Since the distance between the second contact surface 120 and the sensing component is relatively small, and the incident angle of the light scattered by the fingerprint on the second contact surface 120 is relatively small, the obtained second fingerprint image is equivalent to the fingerprint information input on the second contact surface 120, that is, the magnification ratio is relatively small. Therefore, in this embodiment, the processor separates the first fingerprint image and the second fingerprint image according to the different magnification ratios of the first fingerprint image and the second fingerprint image.

[0077] Specifically, as Figure 5 shown, where the position where the light exits from the light source is O, with the first contact surface 110 as the symmetry plane, the mirror image position of the position where the light exits from the light source is the mirror image position O'; with the second contact surface 120 as the symmetry plane, the mirror image of the photosensitive surface (not marked in the figure) of the sensing component 140 is the mirror surface 121.

[0078] Two positions on the first contact surface 110 with a distance r1 therebetween are respectively position A and position B. After the incident light projected to position A and position B undergoes total reflection, the formed waveguide light is respectively projected to position C and position D on the second contact surface 120; after the waveguide light undergoes total reflection again at position C and position D, it is received by the sensing component 140, and the mirror images of the positions where the sensing component 140 receives the waveguide light on the surface 121 are respectively position E and position F.

[0079] As Figure 5 shown, the magnification ratio of the first fingerprint image is the ratio of the distance between position E and position F to the distance between position A and position B, which is equal to the ratio of the distance between the mirror image position O' and the first contact surface 110 to the distance between the mirror image position O' and the mirror surface 121, that is, EF / AB = h3:h1, where h1 represents the distance between the mirror image position O' and the first contact surface 110, and h3 represents the distance between the mirror image position O' and the mirror surface 121.

[0080] The magnification ratio of the second fingerprint image is the ratio of the distance between position E and position F to the distance between position C and position D, which is equal to the ratio of the distance between the mirror image position O' and the mirror surface 121 to the distance between the mirror image position O' and the second contact surface 120, that is, EF / CD = h3:h2, where h2 represents the distance between the mirror image position O' and the second contact surface 120.

[0081] It should be noted that the second fingerprint image is obtained by the sensing component 140 collecting the waveguide light and the light scattered by the fingerprint on the second contact surface.

[0082] For the waveguide light, the magnification ratio of the second fingerprint image is related to the distance between the second contact surface 120 and the photosensitive surface of the sensing component 140. When the distance between the second contact surface 120 and the photosensitive surface of the sensing component 140 is very close, the magnification ratio of its second fingerprint image is very close to 1:1. Compared with the fingerprint on the second contact surface 120, some of the second fingerprint images formed by the waveguide light only have a slight position offset (the offset distance is about a few micrometers) in the direction parallel to the second contact surface 120.

[0083] For the light scattered by the fingerprint on the second contact surface 120, the magnification ratio of the second fingerprint image is mainly based on the distance between the scattering point and the photosensitive surface of the sensing component 140. The smaller the distance between the scattering point and the photosensitive surface of the sensing component 140, the greater the light intensity, and a grayscale image is formed accordingly. That is to say, for the scattered light, the magnification ratio of the second fingerprint image is also related to the distance between the second contact surface 120 and the photosensitive surface of the sensing component 140. When the distance between the second contact surface 120 and the photosensitive surface of the sensing component 140 is very close, the magnification ratio of the second fingerprint image is also very close to 1:1. Compared with the fingerprint on the second contact surface 120, some of the second fingerprint images formed by the scattered light have basically no position offset in the direction parallel to the second contact surface 120.

[0084] It can be seen that the difference between some of the second fingerprint images formed by the waveguide light and some of the second fingerprint images formed by the light scattered by the fingerprint on the second contact surface 120 is only a position offset of a few micrometers in the direction parallel to the second contact surface 120, and the position offset of a few micrometers can be ignored compared with the fingerprint features (about 0.5 mm). Some of the second fingerprint images formed by the waveguide light and some of the second fingerprint images formed by the light scattered by the fingerprint on the second contact surface 120 can be superimposed on each other to obtain the second fingerprint image.

[0085] It should be noted that the magnification ratio of the fingerprint image is related to the relative positional relationship among the contact surface, the sensing component, and the point light source component. In some embodiments, the magnification ratio of the first fingerprint image is about 2.16 times; the magnification ratio of the second fingerprint image is about 1.03 times. However, in other embodiments of the present invention, the magnification ratio of the obtained fingerprint image can be changed by setting the structure of the fingerprint imaging module, so as to obtain a better separation result. It should also be noted that in this embodiment, the fingerprint imaging module is adapted to simultaneously obtain the first fingerprint image of the fingerprint located on the first contact surface and the second fingerprint image of the fingerprint located on the second contact surface, that is, when there are fingerprint contacts on both the first contact surface 110 and the second contact surface 120, the sensing component 140 obtains the first fingerprint image and the second fingerprint image through one light collection. In other embodiments of the present invention, the fingerprint imaging module can also collect fingerprint images on both sides respectively, that is, when there is a fingerprint contact on one of the first contact surface 110 and the second contact surface 120, the sensing component 140 can also receive light to obtain a fingerprint image.

[0086] In addition, an embodiment of the present invention also provides an electronic device. The electronic device includes the above-mentioned fingerprint imaging module.

[0087] In specific implementation, the electronic device can be a terminal such as a mobile phone, a computer, or an electronic lock, a smart lock (such as a smart door lock), a fingerprint lock, etc.

[0088] Reference Figure 6 and Figure 7 , shows a schematic structural diagram of an embodiment of the electronic device of the present invention, where Figure 7 is Figure 6 the cross-sectional structural diagram along the dotted line A2 in

[0089] In this embodiment, the electronic device is a vehicle lock. As Figure 6 and Figure 7 shown, the sensing components 201 / 202 of the fingerprint imaging module in the electronic device are located on the side of the vehicle window glass 210 facing the inside of the vehicle. The electronic device is suitable for starting the vehicle or the in-vehicle system. In other embodiments of the present invention, the vehicle is an autonomous vehicle, and the electronic device is suitable for identifying the identity of passengers, so that even in the back row of the vehicle, the vehicle or the in-vehicle system can be started.

[0090] Reference Figure 8 and Figure 9 , shows a schematic structural diagram of another embodiment of the electronic device of the present invention, where Figure 9 is Figure 8 the cross-sectional structural diagram along the dotted line B2 in

[0091] In this embodiment, the electronic device is a door lock. As Figure 8 and Figure 9 shown, the sensing component 301 of the fingerprint imaging module in the electronic device is disposed on the side of the door body 310 facing the interior of the room. The electronic device can control the opening of the door body through identity recognition. Especially in places with high security requirements such as bank vaults, the electronic device can perform identity recognition on both sides of the door body, thereby further enhancing security assurance.

[0092] It should be noted that when the electronic device is a door lock or a car lock, the fingerprint imaging module mostly adopts single-sided fingerprint recognition, that is, fingerprint recognition is performed on the inner or outer side of the car door or the door body.

[0093] In other embodiments of the present invention, the electronic device may also be a double-sided unlocking device (i.e., a double-sided key) or a blockchain transaction confirmation device, etc.

[0094] In some embodiments of the present invention, the electronic device is a blockchain transaction confirmation device. When both parties in a blockchain transaction are present, but for various reasons, they need to see each other, but they cannot have direct physical contact before the transaction, the electronic device can be used. In operation, both parties press their fingerprints simultaneously, and these fingerprints are simultaneously input in a superimposed manner, encrypted with an algorithm, and after being confirmed and recorded in the blockchain transaction (which cannot be changed), the isolation can be opened, and there is a possibility of direct physical contact between them. The electronic device can achieve the superposition of fingerprint images. Even compared with an electronic device that can obtain a larger surface image, although the electronic device that can obtain a larger surface image can simultaneously collect multiple fingerprint images, it cannot achieve superposition. Moreover, the areas of the first fingerprint image and the second fingerprint image obtained by the electronic device are not equal, and the separation difficulty is lower.

[0095] It should also be noted that the point light source component in the electronic device can be an LED lamp or the display pixels of a display screen as the light source, and the display screen can be set to different light transmittances according to the needs of specific scenarios. The advantage of having a display screen is that user interaction can be performed.

[0096] In addition, the present invention also provides a fingerprint acquisition method adopted by the above fingerprint imaging module.

[0097] Referring to Figure 10 , a flowchart showing an embodiment of the fingerprint acquisition method of the present invention is shown.

[0098] It should be noted that the fingerprint acquisition method is the fingerprint acquisition method adopted by the fingerprint imaging module of the present invention. Therefore, in combination with reference to Figures 1 to 5 , for the specific technical solution of the fingerprint imaging module, refer to the embodiments of the fingerprint imaging module described above, and the present invention will not be elaborated herein.

[0099] First, step S901 is executed to generate incident light, which is reflected successively on the first contact surface 110 and the second contact surface 120, that is, the point light source component 130 generates the incident light. Specifically, generating the incident light includes: driving the point light source component 130 to generate the incident light.

[0100] After that, step S902 is executed to receive the reflected light to obtain a fingerprint image. Specifically, the sensing component 140 receives the reflected light to obtain the fingerprint image.

[0101] As Figures 1 to 5 shown, when receiving the reflected light to obtain a fingerprint image, when there is a fingerprint on the first contact surface, the reflected light is received to obtain a first fingerprint image of the fingerprint located on the first contact surface; when there is a fingerprint on the second contact surface, the reflected light is received to obtain a second fingerprint image of the fingerprint located on the second contact surface.

[0102] In some embodiments of the present invention, when there is a fingerprint contact on the first contact surface, the light reflected successively on the first contact surface and the second contact surface is collected to obtain the first fingerprint image. When there is a fingerprint contact on the second contact surface, the light reflected successively on the first contact surface and the second contact surface and the light scattered by the fingerprint located on the second contact surface are collected to obtain the second fingerprint image.

[0103] It should be noted that for the specific technical solutions for obtaining the first fingerprint image and the second fingerprint image, refer to the description of the foregoing fingerprint imaging module embodiments, and the present invention will not elaborate herein.

[0104] In some embodiments of the present invention, there are fingerprint contacts on both the first contact surface and the second contact surface. Therefore, in the step of obtaining the fingerprint image, the reflected light is received to obtain the first fingerprint image and the second fingerprint image. Therefore, the step of obtaining the fingerprint image further includes: separating the first fingerprint image and the second fingerprint image. Specifically, in this embodiment, the first fingerprint image and the second fingerprint image can be separated according to the different magnification ratios of the first fingerprint image and the second fingerprint image.

[0105] It should be noted that for the specific technical solutions for simultaneously obtaining the first fingerprint image and the second fingerprint image and separating the first fingerprint image and the second fingerprint image, refer to the description of the foregoing fingerprint imaging module embodiments, and the present invention will not elaborate herein.

[0106] It should also be noted that in this embodiment, fingerprints exist on both the first contact surface and the second contact surface. In other embodiments of the present invention, fingerprints exist on only one of the first contact surface and the second contact surface. Therefore, in some other embodiments of the present invention, when fingerprints exist only on the first contact surface, the reflected light is received to obtain a first fingerprint image of the fingerprints located on the first contact surface; when fingerprints exist only on the second contact surface, the reflected light is received to obtain a second fingerprint image of the fingerprints located on the second contact surface.

[0107] In some embodiments, the fingerprint imaging module further includes a first touch screen and a second touch screen. The first touch screen is adapted to sense a touch signal on the first contact surface, and the second touch screen is adapted to sense a touch signal on the second contact surface. The fingerprint acquisition method further includes: determining whether fingerprint touch signals exist on both the first contact surface and the second contact surface. According to the determination result, it is determined whether the light received by the sensing component corresponds to a first fingerprint image, or a second fingerprint image, or a superimposed image of the first fingerprint image and the second fingerprint image.

[0108] Specifically, when the first touch screen senses that a touch signal exists on the first contact surface while the second touch screen senses that no touch signal exists on the second contact surface, the fingerprint acquisition method further includes obtaining a first fingerprint image according to the light received by the sensing component; when the second touch screen senses that a touch signal exists on the second contact surface while the first touch screen senses that no touch signal exists on the first contact surface, the fingerprint acquisition method further includes obtaining a second fingerprint image according to the light received by the sensing component; when the first touch screen senses that a touch signal exists on the first contact surface and at the same time the second touch screen senses that a touch signal exists on the second contact surface, the fingerprint acquisition method further includes obtaining a superimposed image of the first fingerprint image and the second fingerprint image according to the light received by the sensing component, and separating the first fingerprint image and the second fingerprint image according to different magnification ratios of the first fingerprint image and the second fingerprint image.

[0109] In some embodiments, the first touch screen is located between the first contact surface 110 and the sensing component 140, and the second touch screen is located between the second contact surface 120 and the sensing component 140. Specifically, the first touch screen is located between the light-transmitting cover plate 111 and the sensing component 140, and the second touch screen is located between the second contact surface 120 and the photosensitive surface 141.

[0110] In summary, in the present invention, the sensing component and the point light source component are located between the first contact surface and the second contact surface. Therefore, the fingerprint imaging module can obtain fingerprint images from both sides, and the fingerprint imaging module has a wider range of applications.

[0111] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention should be subject to the scope defined by the claims.

Claims

1. A fingerprint imaging module, characterized in that, Comprising: A first contact surface and a second contact surface, the first contact surface and the second contact surface being spaced apart from each other and both being adapted to contact a fingerprint; A point light source assembly and a sensing assembly, the point light source assembly and the sensing assembly being located between the first contact surface and the second contact surface, and a photosensitive surface of the sensing assembly facing the second contact surface; The incident light generated by the point light source assembly is reflected successively on the first contact surface and the second contact surface, and then received by the photosensitive surface of the sensing assembly to obtain a fingerprint image; Wherein, the fingerprint imaging module is adapted to obtain a first fingerprint image of a fingerprint located on the first contact surface and a second fingerprint image of a fingerprint located on the second contact surface; The first fingerprint image is obtained by the sensing assembly collecting the light rays that are successively totally reflected on the first contact surface and the second contact surface by the incident light generated by the point light source assembly, and the second fingerprint image is obtained by the sensing assembly collecting the light rays that are successively totally reflected on the first contact surface and the second contact surface by the incident light generated by the point light source assembly, and / or the light rays scattered by the fingerprint located on the second contact surface.

2. The fingerprint imaging module according to claim 1, wherein Further comprising: A light-transmitting cover plate, the light-transmitting cover plate being located on a side of the point light source assembly facing the first contact surface.

3. The fingerprint imaging module according to claim 2, wherein The first contact surface is a surface of the light-transmitting cover plate facing away from the point light source assembly.

4. The fingerprint imaging module according to claim 1, wherein The second contact surface is a surface of the sensing assembly facing away from the point light source assembly.

5. The fingerprint imaging module according to claim 4, wherein The sensing assembly includes: a light-transmitting layer having opposite first and second surfaces; a photosensitive layer located on the first surface of the light-transmitting layer; The second contact surface is the second surface of the light-transmitting layer.

6. The fingerprint imaging module according to claim 5, wherein The photosensitive layer includes: a substrate and photosensitive pixels located on the substrate, the photosensitive pixels being located between the substrate and the light-transmitting layer.

7. The fingerprint imaging module according to claim 6, wherein The sensing assembly further includes: a mask layer located on a side of the photosensitive pixels facing the first contact surface.

8. The fingerprint imaging module according to claim 1, wherein, The light rays scattered by the fingerprint located on the second contact surface include: ambient light scattered by the fingerprint located on the second contact surface.

9. The fingerprint imaging module according to claim 1, wherein The light rays scattered by the fingerprint located on the second contact surface include: the light rays of the point light source assembly scattered by the fingerprint located on the second contact surface, and ambient light scattered by the fingerprint located on the second contact surface.

10. The fingerprint imaging module according to claim 1, wherein The fingerprint imaging module simultaneously obtains a superimposed image of the first fingerprint image and the second fingerprint image, and the fingerprint imaging module further includes: a processor, the processor being used to separate the first fingerprint image and the second fingerprint image based on the superimposed image.

11. The fingerprint imaging module according to claim 10, characterized in that, The processor is adapted to separate the first fingerprint image and the second fingerprint image according to different magnification ratios of the first fingerprint image and the second fingerprint image.

12. The fingerprint imaging module according to claim 1, wherein, The point light source assembly includes: a plurality of point light sources arranged in an array.

13. The fingerprint imaging module according to claim 12, characterized in that, The point light source assembly includes at least one of: a liquid crystal display screen, an active matrix organic light emitting diode display screen, or a light emitting diode display screen.

14. The fingerprint imaging module according to claim 1, wherein, The point light source assembly includes an LED lamp.

15. An electronic device, characterized in that, Comprising: The fingerprint imaging module according to any one of claims 1 to 14.

16. A fingerprint acquisition method for a fingerprint imaging module according to any one of claims 1 to 14, characterized in that, Comprising: Generate incident light, and the incident light is reflected successively on the first contact surface and the second contact surface; Receive the reflected light to obtain a fingerprint image.

17. The fingerprint acquisition method according to claim 16, characterized in that, When there is a fingerprint contact on the first contact surface, in the step of obtaining a fingerprint image, receive the light that undergoes total internal reflection successively on the first contact surface and the second contact surface to obtain a first fingerprint image of the fingerprint located on the first contact surface; When there is a fingerprint contact on the second contact surface, in the step of obtaining a fingerprint image, receive the light that undergoes total internal reflection successively on the first contact surface and the second contact surface, and / or the light scattered by the fingerprint located on the second contact surface to obtain a second fingerprint image of the fingerprint located on the second contact surface.

18. The fingerprint acquisition method according to claim 16, wherein When there are fingerprint contacts on both the first contact surface and the second contact surface, in the step of obtaining a fingerprint image, receive the light that undergoes total internal reflection successively on the first contact surface and the second contact surface, and the light scattered by the fingerprint located on the second contact surface to obtain the first fingerprint image and the second fingerprint image.

19. The fingerprint acquisition method according to claim 18, wherein The step of obtaining the first fingerprint image includes: Collect the light that undergoes total internal reflection successively on the first contact surface and the second contact surface to obtain the first fingerprint image; The step of obtaining the second fingerprint image includes: Collect the light that undergoes total internal reflection successively on the first contact surface and the second contact surface, and the light scattered by the fingerprint located on the second contact surface to obtain the second fingerprint image.

20. The fingerprint acquisition method according to claim 18, wherein The step of obtaining a fingerprint image further includes: obtaining a superimposed image of the first fingerprint image and the second fingerprint image simultaneously; separating the first fingerprint image and the second fingerprint image based on the superimposed image.

21. The fingerprint acquisition method according to claim 20, wherein The step of separating the first fingerprint image and the second fingerprint image includes: separating the first fingerprint image and the second fingerprint image according to the different magnification ratios of the first fingerprint image and the second fingerprint image.

Images