TOF-based optical fingerprint module

Abstract

The utility model discloses an optical fingerprint module based on TOF, it includes first PCB board, base, module lens, infrared light sensor and radium laser transmitter, the lower surface of first PCB board is provided with ground exposed copper part, base sets up the top of first PCB board, the lower end part of module lens sets up in the inside of base, infrared light sensor sets up below module lens, radium laser transmitter sets up the right side of base. Through radium laser transmitter emission infrared laser signal of module head right side, left side lens and infrared light sensor receive back reflected infrared light, and according to the phase difference between the signal of each part of emission and reception fingerprint, can restore fingerprint line and groove depth etc. information through TOF principle, it can not rely on visible light, but uses the infrared light that naked eye cannot see to make up light, and obtains the 3D information such as fingerprint groove depth in addition to fingerprint image 2D information, improves the security of biological recognition, makes it not need screen luminous to improve the brightness.

Description

Technical Field

[0001] This utility model relates to the field of fingerprint recognition technology, and more specifically, to a TOF-based optical fingerprint module. Background Technology

[0002] As fingerprint module products become increasingly mature, various types of fingerprint modules have emerged. Among them, the more successful products include side fingerprint and under-display optical fingerprint. Ordinary under-display optical fingerprint often requires the screen to emit light to increase brightness in order to ensure sufficient brightness to capture the fingerprint pattern. Moreover, the captured fingerprint image is a 2D image without the depth information of the fingerprint pattern, which reduces the product's competitiveness. Utility Model Content

[0003] The technical problem this invention aims to solve is how to design a TOF-based optical fingerprint module that can use infrared light, which is invisible to the naked eye, to supplement illumination instead of visible light, and obtain 3D information such as the fingerprint groove depth in addition to 2D information of the fingerprint image, thereby improving the security of biometric identification, eliminating the need for screen illumination to increase brightness, and enhancing the competitiveness of the product.

[0004] The technical problem to be solved by this utility model is achieved through the following technical solution:

[0005] To address the aforementioned technical problems, this utility model provides a TOF-based optical fingerprint module, comprising a first PCB board, a base, a module lens, an infrared light sensor, and a laser emitter. The lower surface of the first PCB board has a grounded exposed copper portion. The base is positioned above the first PCB board. The lower portion of the module lens is located inside the base. The infrared light sensor is positioned below the module lens. The laser emitter is positioned on the right side of the base.

[0006] In a preferred embodiment of the TOF-based optical fingerprint module provided by this utility model, the end of the first PCB board is connected to an FPC, and the end of the FPC is connected to a second PCB board.

[0007] In a preferred embodiment of the TOF-based optical fingerprint module provided by this utility model, a connector is provided on the upper surface of the second PCB board.

[0008] In a preferred embodiment of the TOF-based optical fingerprint module provided by this utility model, a silkscreen pattern layer is provided on the lower surface of the second PCB board.

[0009] In a preferred embodiment of the TOF-based optical fingerprint module provided by this utility model, the thickness of both the first PCB board and the second PCB board is 0.35±0.05mm.

[0010] In a preferred embodiment of the TOF-based optical fingerprint module provided by this utility model, the sum of the thicknesses of the second PCB board and the silkscreen pattern layer is 0.38±0.05mm.

[0011] In a preferred embodiment of the TOF-based optical fingerprint module provided by this utility model, the thickness of the FPC is 0.1±0.03mm.

[0012] In a preferred embodiment of the TOF-based optical fingerprint module provided by this utility model, black adhesive is applied to the connection between the FPC and the first PCB board and the base.

[0013] In a preferred embodiment of the TOF-based optical fingerprint module provided by this utility model, the width and height of the black adhesive are both 0.8 mm, and the length of the black adhesive is equal to the width of the FPC.

[0014] In a preferred embodiment of the TOF-based optical fingerprint module provided by this utility model, the connection between the FPC and the first PCB board and the second PCB board is provided with rounded chamfers.

[0015] This utility model has the following beneficial effects:

[0016] TOF stands for Time of Flight, which refers to the time it takes for light to travel through the air. Its principle is based on the phase difference in the time of flight of light reflected from an object, allowing for the reconstruction of the coordinates of various points on the surface of a three-dimensional object, thus reconstructing a three-dimensional image. An infrared laser signal is emitted by a laser emitter on the right side of the module head, while the reflected infrared light is received by a lens and infrared sensor on the left. Based on the phase difference between the emitted and received signals from different parts of the fingerprint, the TOF principle can reconstruct information such as fingerprint ridges and groove depth. It can use infrared light, invisible to the naked eye, to supplement illumination instead of visible light, and acquire 3D information such as fingerprint groove depth in addition to the 2D information of the fingerprint image. This improves the security of biometric identification, eliminates the need for screen illumination to increase brightness, and enhances the product's competitiveness. Attached Figure Description

[0017] To more clearly illustrate the solutions in this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the structure of a TOF-based optical fingerprint module provided by this utility model.

[0019] Figure 2 for Figure 1 The right view.

[0020] Figure 3 for Figure 1 Rear view.

[0021] Explanation of icon numbers:

[0022] 1. First PCB board; 2. Base; 3. Module lens; 4. Infrared light sensor; 5. Laser emitter; 6. Grounding exposed copper part; 7. FPC; 8. Second PCB board; 9. Connector; 10. Silk screen pattern layer; 11. Black glue; 12. Rounded chamfer. Detailed Implementation

[0023] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0024] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0025] Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first," "second," or "third" may explicitly or implicitly include at least one of that feature. In the description of this utility model, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0026] This utility model provides a TOF-based optical fingerprint module, which includes a first PCB board, a base, a module lens, an infrared light sensor, and a laser emitter. The lower surface of the first PCB board is provided with a grounded exposed copper portion. The base is disposed above the first PCB board. The lower part of the module lens is disposed inside the base. The infrared light sensor is disposed below the module lens. The laser emitter is disposed on the right side of the base.

[0027] TOF stands for Time of Flight, which refers to the time it takes for light to travel through the air. Its principle is based on the phase difference in the time of flight of light reflected from an object, allowing for the reconstruction of the coordinates of various points on the surface of a three-dimensional object, thus reconstructing a three-dimensional image. An infrared laser signal is emitted by a laser emitter on the right side of the module head, while the reflected infrared light is received by a lens and infrared sensor on the left. Based on the phase difference between the emitted and received signals from different parts of the fingerprint, the TOF principle can reconstruct information such as fingerprint ridges and groove depth. It can use infrared light, invisible to the naked eye, to supplement illumination instead of visible light, and acquire 3D information such as fingerprint groove depth in addition to the 2D information of the fingerprint image. This improves the security of biometric identification, eliminates the need for screen illumination to increase brightness, and enhances the product's competitiveness.

[0028] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. The present invention will be described in detail below with reference to the accompanying drawings and embodiments, examples of which are shown in the drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0029] Example 1, please refer to Figures 1 to 3This invention provides a TOF-based optical fingerprint module, which includes a first PCB board 1, a base 2, a module lens 3, an infrared light sensor 4, and a laser emitter 5. The lower surface of the first PCB board 1 is provided with a grounded exposed copper part 6; the base 2 is located above the first PCB board 1; the lower part of the module lens 3 is located inside the base 2; the infrared light sensor 4 is located below the module lens 3; and the laser emitter 5 is located on the right side of the base 2. TOF stands for Time of Flight, which refers to the time it takes for light to travel through the air. Its principle is based on the phase difference in the time of flight of light reflected from an object, allowing for the reconstruction of the coordinates of various points on the surface of a three-dimensional object, thus reconstructing a three-dimensional image. An infrared laser signal is emitted by a laser emitter 5 on the right side of the module head, while the reflected infrared light is received by a lens and infrared light sensor 4 on the left. Based on the phase difference between the emitted and received signals from different parts of the fingerprint, the TOF principle can reconstruct information such as fingerprint ridges and groove depth. It can use infrared light, invisible to the naked eye, to supplement illumination instead of visible light, and acquire 3D information such as fingerprint groove depth in addition to the 2D information of the fingerprint image. This improves the security of biometric identification, eliminates the need for screen illumination to increase brightness, and enhances the product's competitiveness.

[0030] In addition, the exposed copper part 6 can ground the entire optical fingerprint module to external components, thereby enabling the discharge of static electricity.

[0031] Example 2, please refer to Figures 1 to 3 As a further optimization of Embodiment 1, in this embodiment, the first PCB board 1 is further connected to an FPC 7 at one end, and the second PCB board 8 is connected to the other end of the FPC 7. The first PCB board 1 and the second PCB board 8 are connected through the FPC 7, thereby enabling the second PCB board 8 to be bent, so as to facilitate the connection of the second PCB board 8 with other components. Furthermore, a connector 9 is provided on the upper surface of the second PCB board 8, so that the optical fingerprint module can be connected to external components through the connector 9.

[0032] Furthermore, the lower surface of the second PCB board 8 is provided with a silkscreen pattern layer 10, which can be used for installation alignment, improving installation efficiency and reducing installation costs.

[0033] Furthermore, the thickness of the first PCB board 1 and the second PCB board 8 is 0.35±0.05mm, the sum of the thickness of the second PCB board 8 and the silkscreen pattern layer 10 is 0.38±0.05mm, and the thickness of the FPC7 is 0.1±0.03mm.

[0034] Furthermore, black adhesive 11 is provided at the connection between FPC7 and the first PCB board 1 and the base 2. The width and height of the black adhesive 11 are both 0.8mm, and the length of the black adhesive 11 is equal to the width of FPC7. The black adhesive 11 can effectively strengthen the bending part and prevent cracking at this point.

[0035] Furthermore, rounded chamfers 12 are provided at the connection points between FPC7 and the first PCB board 1 and the second PCB board 8 to prevent the connection points from being easily torn due to stress concentration.

[0036] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0037] Obviously, the embodiments described above are only some embodiments of this application, not all embodiments. The accompanying drawings show preferred embodiments of this application, but do not limit the patent scope of this application. This application can be implemented in many different forms; rather, the purpose of providing these embodiments is to provide a more thorough and comprehensive understanding of the disclosure of this application. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing specific embodiments, or make equivalent substitutions for some of the technical features. Any equivalent structures made using the content of this application's specification and drawings, directly or indirectly applied to other related technical fields, are similarly within the scope of patent protection of this application.

Claims

1. A Time-of-Flight (TOF) based optical fingerprint module, characterized in that, It includes: The first PCB board has a grounded exposed copper section on its lower surface; A base is disposed above the first PCB board; The lower part of the module lens is disposed inside the base; An infrared light sensor is located below the module lens; A laser emitter is located on the right side of the base.

2. The TOF-based optical fingerprint module according to claim 1, characterized in that, The first PCB board is connected to an FPC at one end, and the FPC is connected to a second PCB board at one end.

3. The TOF-based optical fingerprint module according to claim 2, characterized in that, A connector is provided on the upper surface of the second PCB board.

4. The TOF-based optical fingerprint module according to claim 3, characterized in that, The lower surface of the second PCB board is provided with a silkscreen pattern layer.

5. The TOF-based optical fingerprint module according to claim 2, characterized in that, The thickness of both the first PCB board and the second PCB board is 0.35±0.05mm.

6. The TOF-based optical fingerprint module according to claim 4, characterized in that, The sum of the thicknesses of the second PCB board and the silkscreen pattern layer is 0.38±0.05mm.

7. The TOF-based optical fingerprint module according to claim 2, characterized in that, The thickness of the FPC is 0.1 ± 0.03 mm.

8. The TOF-based optical fingerprint module according to claim 2, characterized in that, Black adhesive is applied to the connection points between the FPC and the first PCB board and the base.

9. The TOF-based optical fingerprint module according to claim 8, characterized in that, The black adhesive has a width and height of 0.8 mm, and its length is equal to the width of the FPC.

10. The TOF-based optical fingerprint module according to claim 2, characterized in that, The connection points between the FPC and the first PCB board and the second PCB board are all provided with rounded chamfers.

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