Optical fingerprint identification module and device and electronic equipment

Abstract

The embodiment of the utility model provides an optical fingerprint recognition module and device and electronic equipment, the optical fingerprint recognition module comprises a camera, a shading part is arranged around the camera, and the camera and the shading part are arranged between the lower surface of a cover plate and a printed circuit board. The shading piece is used for shading light emitted by a light source to the side wall or the top of the camera and enabling the light emitted by the light source to enter the interior of a human finger on the upper surface of the cover plate and enter a view field area of the camera in a diffusion and transmission mode so as to form a fingerprint detection signal; the camera is used for receiving the fingerprint detection signal and detecting fingerprint information of the human finger according to the received fingerprint detection signal. According to the embodiment of the invention, the size of the optical fingerprint identification module is reduced, the human finger identification rate is improved, and true and false fingers can be distinguished.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of fingerprint recognition technology, and in particular to an optical fingerprint recognition module, device and electronic device. Background Art

[0002] With the development of optical under-screen fingerprint recognition technology, it is widely used in terminal devices such as smartphones that use screen self-luminescence for image acquisition and recognition, and is also used in electronic devices such as access control or car locks that use external light sources for image acquisition and recognition. However, for image acquisition and recognition solutions that use external light sources, large structural parts such as triangular prisms are usually used, resulting in the size of the optical fingerprint recognition module being too large and difficult to miniaturize. In addition, its optical path design will have the defect of low finger recognition rate for dry fingers, and it is also impossible to distinguish between 3D fake fingers and real fingers made of materials such as silicone.

[0003] Therefore, how to better implement fingerprint recognition in electronic devices that use external light sources for image acquisition and recognition has become a technical problem that needs to be solved urgently. Utility Model Content

[0004] In view of this, one of the technical problems solved by the embodiments of the present application is to provide an optical fingerprint recognition module, device and electronic device, which reduce the size of the optical fingerprint recognition module and improve the recognition rate of human fingers, and can distinguish between real and fake fingers.

[0005] In a first aspect, an optical fingerprint recognition module is provided, comprising: a camera, a shading member arranged around the camera, the camera and the shading member being arranged between a lower surface of a cover and a printed circuit board, the shading member being used to block light emitted from a light source toward a side wall or a top of the camera and allowing light emitted by the light source to enter an interior of a human finger on an upper surface of the cover, and enter a field of view of the camera by diffusion and transmission to form a fingerprint detection signal; the camera being used to receive the fingerprint detection signal, and detect fingerprint information of the human finger according to the received fingerprint detection signal.

[0006] In a second aspect, an optical fingerprint recognition device is provided. The optical fingerprint recognition device is arranged under a cover plate, and the optical fingerprint recognition device comprises: a shading plate and the optical fingerprint recognition module described in the first aspect.

[0007] In a third aspect, an electronic device is provided, comprising: a cover plate and the optical fingerprint recognition device according to the second aspect, wherein the optical fingerprint recognition device is arranged under the cover plate to realize fingerprint information detection of human fingers.

[0008] In the scheme of the embodiment of the present application, the optical fingerprint recognition module includes: a camera with a shading member arranged around it, the camera and the shading member are arranged between the lower surface of the cover plate and the printed circuit board, the shading member blocks the irradiation light from the light source to the side wall or top of the camera and allows the light emitted by the light source to enter the inside of the human finger on the upper surface of the cover plate, and enter the camera's field of view by diffusion and transmission to form a fingerprint detection signal. The camera of the embodiment of the present application detects the fingerprint information of the human finger according to the received fingerprint detection signal, without the need to use large structural parts such as triangular prisms, thereby reducing the size of the optical fingerprint recognition module, facilitating the miniaturization of the device, and meeting the use needs of more application scenarios. The light emitted by the light source of the embodiment of the present application enters the camera's field of view by diffusion and transmission inside the human finger, and even if the dry finger is not in good contact with the cover plate, it will not affect the finger recognition rate. In addition, since there are differences in the intensity and distribution of the transmitted light components of the 3D fake finger and the real finger, which in turn causes differences in the light intensity distribution of the fingerprint image, the embodiment of the present application can distinguish between real and fake fingers. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Hereinafter, some specific embodiments of the present application will be described in detail in an exemplary and non-limiting manner with reference to the accompanying drawings. The same reference numerals in the accompanying drawings indicate the same or similar components or parts. It should be understood by those skilled in the art that these drawings are not necessarily drawn to scale. In the accompanying drawings:

[0010] Figure 1 A schematic diagram of the structure of an optical fingerprint recognition module that uses an external light source for image acquisition and recognition;

[0011] Figure 2 This is a schematic diagram of the structure of an optical fingerprint recognition module according to an embodiment of the present application;

[0012] Figure 3a A schematic diagram of an optical fingerprint recognition module according to an embodiment of the present application for fingerprint recognition of a real finger;

[0013] Figure 3b A schematic diagram of an optical fingerprint recognition module according to an embodiment of the present application for fingerprint recognition of a fake finger;

[0014] Figure 4 This is a schematic diagram of another light shielding area of ​​an optical fingerprint recognition module according to an embodiment of the present application;

[0015] Figure 5 A schematic diagram of a light shielding area of ​​an optical fingerprint recognition module according to another embodiment of the present application;

[0016] Figure 6 A schematic top view of a light source arrangement according to an embodiment of the present application;

[0017] Figure 7This is a flowchart of the steps of an optical fingerprint recognition method according to an embodiment of the present application;

[0018] Figure 8 This is a flowchart of step S3 in the optical fingerprint recognition method according to another embodiment of the present application. DETAILED DESCRIPTION

[0019] The specific implementation of the embodiment of the present utility model is further described below in conjunction with the accompanying drawings of the embodiment of the present utility model.

[0020] Optical under-screen fingerprint recognition technology is a technology that uses optical principles to obtain and identify fingerprints. The following briefly discusses the basic principles of optical under-screen fingerprint recognition technology:

[0021] ① Capture image: The human finger is placed on the fingerprint scanning area on the upper surface of the cover, and the light source emits light to illuminate the human finger. The light passes through the micro-optical system of the optical fingerprint recognition module (usually including lenses, filters, etc.) and forms an image on the optical fingerprint sensor of the optical fingerprint recognition module.

[0022] ② Generate an image: The ridges and valleys of a person’s fingerprint differ in the reflection or transmission of light, forming an image of the fingerprint.

[0023] ③ Image analysis and recognition: Usually the image is preprocessed first (such as removing noise, sharpening the image, etc.), and then the fingerprint features (such as ridge endings, bifurcations and short ridges, etc.) are extracted and stored to form a data called a fingerprint template. When fingerprint matching is performed, only the fingerprint template is compared, not the complete fingerprint image.

[0024] ④Matching and verification: When there is a new fingerprint image that needs to be verified, the system will repeat the above steps of image capture and generation, image processing and feature extraction, and then compare the new fingerprint template with the stored fingerprint template. If the two match, the system confirms that the fingerprint verification is successful.

[0025] Currently, there are two main application scenarios for optical under-screen fingerprint recognition technology: 1. Terminal devices that use screen self-luminescence as a light source for image acquisition and recognition, such as mobile phones, tablets and other terminal products; 2. Electronic devices that use external light sources for image acquisition and recognition, such as attendance machines, access control, car locks and other terminal products.

[0026] The embodiments of the present application are applicable to any electronic device that uses an external light source to perform image acquisition and recognition, such as attendance machines, door locks, vehicle locks (or other vehicle-mounted electronic devices), and other electronic devices.

[0027] See also Figure 1The optical fingerprint recognition module that uses an external light source for image acquisition and recognition usually uses a triangular prism to fully reflect the parallel light or nearly parallel light emitted by the light source, and then enters the optical fingerprint sensor for imaging through the optical system of the optical fingerprint recognition module.

[0028] When a human finger presses on the upper surface of the triangular prism, the contact between the ridge of the human finger and the upper surface of the prism will destroy the total reflection state of light, causing part of the light to be absorbed by the ridge of the finger, while the valley of the finger is in contact with the upper surface of the prism and is not affected, forming a fingerprint image with dark ridges and bright valleys on the optical fingerprint sensor.

[0029] In low-temperature scenarios, less sweat and oil secretion from fingers will cause the fingers to be dry. The ridges of dry fingers do not contact well with the prism surface, resulting in broken ridges in the image, affecting algorithm recognition and causing low recognition rates for human fingers. Using materials such as silicone to make 3D fake fingerprints instead of human fingers to press on the upper surface of the prism can also form fingerprint images with dark ridges and bright valleys, which can easily lead to fingerprint recognition errors due to the inability to distinguish between 3D fake fingerprints and real fingers.

[0030] In order to overcome the above technical defects, the optical fingerprint recognition module of the embodiment of the present application includes: a camera with a shading member arranged around it, the camera and the shading member are arranged between the lower surface of the cover and the printed circuit board, the shading member blocks the light emitted by the light source to the side wall or top of the camera and allows the light emitted by the light source to enter the inside of the human finger on the upper surface of the cover, and enter the camera's field of view by diffusion and transmission to form a fingerprint detection signal. The camera of the embodiment of the present application detects the fingerprint information of the human finger according to the received fingerprint detection signal, without the need to use large structural parts such as triangular prisms, reducing the size of the optical fingerprint recognition module, facilitating the miniaturization of the device, and meeting the use needs of more application scenarios.

[0031] The light emitted by the light source of the embodiment of the present application enters the camera's field of view by diffusion and transmission inside the human finger. Even if the dry finger is not in good contact with the cover plate, it will not affect the finger recognition rate. In addition, due to the difference in the intensity and distribution of the transmitted light component between the 3D fake finger and the real finger, which in turn causes the difference in the light intensity distribution of the fingerprint image, the embodiment of the present application can distinguish between real and fake fingers.

[0032] See also Figure 2 , an embodiment of the present application provides an optical fingerprint recognition module, which is arranged under the cover plate 1.

[0033] Specifically, the cover plate 1 can be made of glass, acrylic, or other light-transmitting materials.

[0034] The optical fingerprint recognition module includes: a camera 2. A shading member 3 is arranged around the camera 2. The camera 2 and the shading member 3 are used to be arranged between the lower surface of the cover plate 1 and the printed circuit board 4. The shading member 3 is used to block the light from the light source 5 to the side wall or top of the camera 2 and allow the light from the light source 5 to enter the inside of the human finger on the upper surface of the cover plate 1, and enter the field of view of the camera 2 by diffusion and transmission to form a fingerprint detection signal. The camera 2 is used to receive the fingerprint detection signal and detect the fingerprint information of the human finger according to the received fingerprint detection signal.

[0035] Specifically, the camera 2 includes a micro-optical system (usually including a lens, a filter, etc.) and an optical fingerprint sensor. Light enters the field of view of the micro-optical system of the camera 2 to form a fingerprint detection signal, and the fingerprint detection signal enters the optical fingerprint sensor to form an image of the fingerprint.

[0036] The embodiment of the present application does not require the use of large structural parts such as triangular prisms, thereby reducing the size of the optical fingerprint recognition module, facilitating the miniaturization of the device, and meeting the needs of more application scenarios.

[0037] The light emitted by the light source 5 of the embodiment of the present application enters the field of view of the camera 2 by diffusion and transmission inside the human finger. Even if the dry finger is not in good contact with the cover plate, it will not affect the finger recognition rate.

[0038] Also, see Figure 3a and Figure 3b Since there are differences in the intensity and distribution of the transmitted light components between the 3D fake finger and the real finger, which in turn causes differences in the light intensity distribution of the fingerprint image of the 3D fake finger and the real finger, the embodiments of the present application can distinguish between real and fake fingers.

[0039] In some specific implementations of the embodiments of the present application, the shading member 3 is arranged between the lower surface of the cover plate 1 and the printed circuit board 4 to provide supporting force, so the assembly of the optical fingerprint recognition module can be achieved without setting other components to provide supporting force between the lower surface of the cover plate 1 and the printed circuit board 4.

[0040] In some other specific implementations of the embodiments of the present application, a support member 6 is arranged around the optical fingerprint recognition module, and the support member 6 is arranged between the lower surface of the cover plate 1 and the printed circuit board 4 to provide a supporting force. In the embodiments of the present application, a support member 6 is arranged around the optical fingerprint recognition module, so as to provide a supporting force between the lower surface of the cover plate 1 and the printed circuit board 4, so as to improve the assembly stability of the optical fingerprint recognition module.

[0041] Specifically, the support members 6 are arranged at equal intervals around the optical fingerprint recognition module, thereby further ensuring that a more stable supporting force is provided.

[0042] In some specific implementations of the embodiments of the present application, the irradiation surface of at least one of the support member 6, the shading member 3 and the printed circuit board 4 has a surface structure for eliminating stray light, and the irradiation surface is a surface in contact with the light emitted by the light source 5. The embodiments of the present application further eliminate the stray light generated by the light emitted by the light source irradiating the irradiation surface of at least one of the support member 6, the shading member 3 and the printed circuit board 4.

[0043] Specifically, the surface structure is a surface layer that is frosted, painted matte black, etc., so that stray light can be eliminated through a simple process.

[0044] In some specific implementations of the embodiments of the present application, the shading member 3 includes: a main body portion 31 and a flange portion 32, the camera 2 is embedded or fixed in the main body portion 31, the flange portion 32 is in contact with the lower surface of the cover plate 1, and the flange portion 32 extends in a direction away from the camera 2 to cover the light-emitting area of ​​the light source 5.

[0045] The embodiment of the present application uses the structure of the light shielding member 3 to not only fix the camera 2 through the main body 31, but also covers the light emitting area of ​​the light source 5 through the flange 32, so that the light emitted by the light source 5 can enter the inside of the human finger on the upper surface of the cover plate 1. The embodiment of the present application further avoids the light emitted by the light source 5 from entering the camera's field of view by reflection inside the cover plate 1 and affecting the accuracy of the fingerprint detection signal.

[0046] In some specific implementations of the embodiments of the present application, the shading member 3 is attached to the lower surface of the cover plate 1 to form a shading area, and the shading member 3 is attached to the lower surface of the cover plate 1 in one of the following ways:

[0047] The shading member 3 is attached to the lower surface of the cover plate 1 through the shading adhesive 7;

[0048] The shading member 3 is attached to the lower surface of the cover plate 1 through a structural member (not shown in the figure);

[0049] The shading member 3 is adapted to fit on the lower surface of the cover plate 1 by the distance between the cover plate 1 and the printed circuit board 4 .

[0050] In the embodiment of the present application, the shading member 3 is attached to the lower surface of the cover plate 1 by means of the shading glue 7. The shading glue 7 adopts a light-absorbing glue, which makes the assembly simpler and enables the shading member 3 to be firmly attached to the lower surface of the cover plate 1.

[0051] For example, the light shielding glue 7 can be made of one of PE (polyethylene), PET (polyethylene terephthalate), and PP (polypropylene).

[0052] Specifically, in order to prevent the light emitted by the light source 5 from being reflected multiple times in the cover plate 1 and entering the field of view of the camera 2, the light shielding glue 7 is a light absorbing material, and the refractive index of the light shielding glue 7 is consistent with the refractive index of the cover plate 1. Due to the material of the light shielding glue 7 and the cover plate 1, the refractive index of the light shielding glue 7 and the refractive index of the cover plate 1 can be close.

[0053] In some specific implementations of the embodiments of this application, see Figure 2 A touch ring 8 is provided between the shading member 3 and the lower surface of the cover plate 1 , and the touch ring 8 is used to detect a pressing operation of a human finger.

[0054] If a human finger presses the upper surface of the cover plate 1, it indicates that there is a pressing operation of the human finger. The embodiment of the present application wakes up the optical fingerprint recognition module, and the optical fingerprint recognition module uses optical principles to obtain and recognize the fingerprint.

[0055] Specifically, if the shading member 3 is attached to the lower surface of the cover plate 1 through the shading adhesive 7 , the touch ring 8 is arranged between the shading adhesive 7 and the shading member 3 .

[0056] See also Figure 6 , only taking the light source as LED as an example, in order to obtain a more uniform fingerprint detection signal, the light sources 5 are arranged at equal intervals around the camera 2. The embodiment of the present application does not limit the number and installation position of the light sources 5. Preferably, in order to improve the uniformity of the light source 5 irradiating the human finger to obtain a more uniform fingerprint detection signal, the distances between the multiple light sources 5 and the optical axis of the lens of the camera 2 are equal.

[0057] In order to further improve the uniformity of lighting, refer to Figure 4 and Figure 5 A light homogenizing plate 51 is provided on the light source 5 , and the light homogenizing plate 51 covers the light emitting area of ​​the light source 5 and homogenizes the light emitted by the light source 5 .

[0058] Specifically, the light diffuser 51 is a continuous or discontinuous circular ring, a square ring, or other shapes. For ease of assembly, the light diffuser 51 is a continuous or discontinuous circular ring.

[0059] See also Figure 2 The embodiment of the present application further provides an optical fingerprint recognition device. The optical fingerprint recognition device is arranged below the cover plate 1, and the optical fingerprint recognition device comprises: a light shielding member 3 and an optical fingerprint recognition module in any of the above embodiments.

[0060] See also Figure 2 Another embodiment of the present application further provides an electronic device, comprising: a cover plate 1 and the optical fingerprint recognition device in the above embodiment, wherein the optical fingerprint recognition device is arranged under the cover plate 1 to realize fingerprint information detection of human fingers.

[0061] Corresponding to the above-mentioned optical fingerprint recognition module, an embodiment of the present application further provides an optical fingerprint recognition method, which is applied to any of the above-mentioned optical fingerprint recognition modules.

[0062] See also Figure 7 , methods include:

[0063] Step S1: shielding the light emitted from the light source to the side wall or top of the camera by a shading member arranged around the camera and allowing the light emitted by the light source to enter the inside of the human finger on the upper surface of the cover plate.

[0064] Step S2: Allow the light from the human finger on the upper surface of the cover to enter the camera's field of view through diffusion and transmission to form a fingerprint detection signal.

[0065] Step S3: receiving a fingerprint detection signal, and detecting fingerprint information of a human finger according to the received fingerprint detection signal.

[0066] See also Figure 8 , the method of another embodiment of the present application, step S3 comprises:

[0067] Step S31: determining the light intensity distribution of the fingerprint image according to the fingerprint detection signal, and distinguishing between real and fake fingers through the light intensity distribution.

[0068] Step S32: If it is determined to be a real finger, the fingerprint information of the human finger is identified according to the fingerprint detection signal.

[0069] The camera of the embodiment of the present application detects the fingerprint information of the human finger according to the received fingerprint detection signal. There is no need to use large structural parts such as triangular prisms, which reduces the size of the optical fingerprint recognition module, facilitates the miniaturization of the equipment, and meets the use needs of more application scenarios. The light emitted by the light source of the embodiment of the present application enters the field of view of the camera through diffusion and transmission inside the human finger. Even if the dry finger is not in good contact with the cover plate, it will not affect the finger recognition rate. In addition, due to the difference in the intensity and distribution of the transmitted light component of the 3D fake finger and the real finger, which in turn causes the difference in the light intensity distribution of the fingerprint image, the embodiment of the present application can distinguish between real and fake fingers.

[0070] The electronic equipment of the embodiment of the present application includes but is not limited to:

[0071] (1) Mobile communication devices: These devices are characterized by their mobile communication functions and their main purpose is to provide voice and data communications. These terminals include: smart phones (such as iPhone), multimedia phones, functional phones, and low-end phones.

[0072] (2) Ultra-mobile personal computer devices: These devices fall into the category of personal computers, have computing and processing capabilities, and generally also have mobile Internet access features. These terminals include: PDA, MID and UMPC devices, such as iPad.

[0073] (3) Portable entertainment devices: These devices can display and play multimedia content. They include audio and video players (such as iPods), handheld game consoles, e-books, smart toys, and portable car navigation devices.

[0074] (4) Door locks, vehicle locks and other electronic devices with data interaction functions.

[0075] Thus far, specific embodiments of the subject matter have been described. Other embodiments are within the scope of the appended claims. In some cases, the actions recited in the claims may be performed in a different order and still achieve the desired results. Additionally, the processes depicted in the accompanying drawings do not necessarily require the specific order or sequential order shown to achieve the desired results. In some embodiments, multitasking and parallel processing may be advantageous.

[0076] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, commodity or device including the elements.

[0077] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0078] The above are only embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included within the scope of the claims of the present application.

Claims

1. An optical fingerprint recognition module, characterized in that: The optical fingerprint recognition module includes: a camera, a shading member is arranged around the camera, the camera and the shading member are used to be arranged between the lower surface of the cover and the printed circuit board, the shading member is used to block the light from the light source to the side wall or top of the camera and allow the light emitted by the light source to enter the inside of the human finger on the upper surface of the cover, and enter the field of view of the camera by diffusion and transmission to form a fingerprint detection signal; the camera is used to receive the fingerprint detection signal and detect the fingerprint information of the human finger according to the received fingerprint detection signal.

2. The optical fingerprint recognition module according to claim 1, characterized in that: The optical fingerprint recognition module also includes a support member arranged between the lower surface of the cover plate and the printed circuit board, the support member is used to provide a supporting force between the lower surface of the cover plate and the printed circuit board, and the irradiation surface of at least one of the support member, the shading member and the printed circuit board has a surface structure for eliminating stray light, and the irradiation surface is a surface that contacts the light emitted by the light source.

3. The optical fingerprint recognition module according to claim 1, characterized in that: The shading member includes: a main body and a flange portion, the camera is embedded or fixed in the main body, the flange portion is in contact with the lower surface of the cover plate, and the flange portion extends in a direction away from the camera to cover the light emitting area of ​​the light source.

4. The optical fingerprint recognition module according to claim 1, characterized in that: The shading member is attached to the lower surface of the cover plate to form a shading area, and the shading member is attached to the lower surface of the cover plate in one of the following ways: The shading member is attached to the lower surface of the cover plate by means of shading adhesive; The shading member is attached to the lower surface of the cover plate through a structural member; The shading member is adapted to fit on the lower surface of the cover plate through the distance between the cover plate and the printed circuit board.

5. The optical fingerprint recognition module according to claim 4, characterized in that: The light-shielding glue is a light-absorbing material, and the refractive index of the light-shielding glue is consistent with the refractive index of the cover plate.

6. The optical fingerprint recognition module according to claim 1, characterized in that: The light sources are arranged around the camera at equal intervals.

7. The optical fingerprint recognition module according to claim 1, characterized in that: The light source is provided with a light homogenizing plate, which covers the light emitting area of ​​the light source and homogenizes the light emitted by the light source. The light homogenizing plate is used to be set as a continuous or discontinuous ring.

8. The optical fingerprint recognition module according to claim 3, characterized in that: A touch ring is arranged between the flange portion of the shading member and the lower surface of the cover plate, and the touch ring is used to detect a pressing operation of a finger of the human body.

9. An optical fingerprint recognition device, characterized in that: The optical fingerprint recognition device is arranged below the cover plate, and comprises: a shading member and the optical fingerprint recognition module according to any one of claims 1 to 8.

10. An electronic device, characterized in that: include: The cover plate and the optical fingerprint recognition device as claimed in claim 9, wherein the optical fingerprint recognition device is arranged under the cover plate to realize fingerprint information detection of human fingers.

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