CN111832355B - Fingerprint identification module - Google Patents

Abstract

The invention provides a fingerprint identification module, which includes a contact layer, a light source that can generate a light beam, an image sensing element and a lens. The contact layer is exposed outside the fingerprint recognition module and can be in contact with the user's finger. The image sensing element is located below the contact layer to receive the light beam and generate a fingerprint image corresponding to the finger. The lens is located between the contact layer and the image sensing element, and the lens has a plurality of openings for light beams to pass through and be projected to the image sensing element. Among them, the design of the diameters of the multiple openings and their arrangement can improve the identification accuracy of the fingerprint identification module.

Description

Fingerprint identification module

Technical field

The present invention relates to an identity recognition element, and in particular to a fingerprint recognition module for identifying a user's identity through fingerprints.

Background technique

In recent years, identity recognition components have been used in various electronic products. Identity recognition components are, for example, fingerprint recognition modules using fingerprint recognition technology or face recognition modules using cameras and facial feature recognition technology. Taking the fingerprint recognition module as an example, it allows the user to input his or her fingerprint into the electronic device and archive the electronic device. The user can then input his or her fingerprint through the fingerprint recognition module to unlock the electronic device. The use of fingerprint recognition technology to unlock electronic devices is faster and more convenient than the previous unlocking method of manually entering a password, so it is favored by users, and the demand for fingerprint recognition modules has also increased significantly.

Fingerprint identification technologies that have been widely used include at least capacitive, optical, ultrasonic and other fingerprint identification technologies. Among them, because the optical fingerprint recognition technology does not need to cut the touch panel (or screen) like the capacitive fingerprint recognition technology, the optical fingerprint recognition technology is gradually favored and widely used. Especially the under-screen optical fingerprint identification technology (On-Screen Fingerprint Identification Technology), whose fingerprint identification module is set under the organic light-emitting diode (OLED) screen (hereinafter referred to as the OLED screen) and is not exposed outside the electronic device, so The under-screen optical fingerprint recognition technology has received special attention.

A fingerprint identification module using under-screen optical fingerprint identification technology includes an image sensing element, an OLED screen, and a microprocessor. The image sensing element is a charge-coupled device (CCD) or a contact image sensing element (CIS). The OLED screen can generate a light beam. When a finger is placed on the OLED screen, the light beam can be projected to the finger on the OLED screen, and the light beam is reflected by the finger to be received by the image sensing element. The image sensing element can sense the light beam to generate a fingerprint image corresponding to the finger. The microprocessor can use the fingerprint recognition algorithm to identify the fingerprint image to perform the fingerprint recognition process, and can perform unlocking work or authentication work after the fingerprint image passes the fingerprint recognition process.

However, with the advancement of technology, the requirements for the accuracy of the operation of fingerprint recognition modules have also increased. Therefore, there is a need for a fingerprint identification module that can improve the accuracy of the fingerprint identification module.

Contents of the invention

The purpose of the present invention is to provide a fingerprint identification module that can improve operating accuracy.

In a preferred embodiment, the present invention provides a fingerprint recognition module including a contact layer, at least one light source, at least one image sensing element and a lens. The contact layer is exposed outside the fingerprint recognition module and is used to contact a finger. The at least one light source is used to generate at least one light beam, and the at least one light beam is projected to the contact layer. The at least one image sensing element is located below the contact layer and is used to receive the at least one light beam and generate a corresponding fingerprint image. The lens is located between the contact layer and the at least one image sensing element, and the lens has a plurality of openings for allowing the at least one light beam to pass through and be projected to the at least one image sensing element; wherein, the plurality of openings are The diameter of at least one of the openings is between 7.2 micrometer and 12 micrometer.

In a preferred embodiment, the present invention also provides a fingerprint recognition module, including a contact layer, at least one light source, at least one image sensing element and a lens. The contact layer is exposed outside the fingerprint recognition module and is used to contact a finger. The at least one light source is used to generate at least one light beam, and the at least one light beam is projected to the contact layer. The at least one image sensing element is located below the contact layer and is used to receive the at least one light beam and generate a corresponding fingerprint image. The lens is located between the contact layer and the at least one image sensing element, and the lens has a plurality of openings for allowing the at least one light beam to pass through and be projected to the at least one image sensing element; wherein, each The image sensing element includes at least one sensing area and at least one light-shielding area. The at least one sensing area is used to receive the at least one light beam and generate a corresponding fingerprint image. The light shielding area is located below the at least one sensing area and surrounds the at least one sensing area to shield the at least one light beam. The length of the at least one sensing area is 42.8 microns, the distance between every two sensing areas is 7.2 microns, and the length of the at least one light-shielding area is 50 microns.

The beneficial effect of the present invention is that according to the special design of the lens in the fingerprint identification module of the present invention, better light transmission efficiency can be obtained, thereby improving the identification accuracy of the fingerprint identification module and solving the problems caused by the known technology.

Description of the drawings

Figure 1 is a schematic cross-sectional view of a partial structure of a fingerprint identification module in a preferred embodiment of the present invention.

2A to 2C are schematic top views of the partial structure of the lens of the fingerprint recognition module of the present invention in a preferred embodiment.

FIG. 3 is a schematic top view of the partial structure of multiple image sensing elements of the fingerprint recognition module of the present invention in a preferred embodiment.

4 is a schematic top view of the partial structure of the lens and multiple image sensing elements of the fingerprint recognition module of the present invention in a preferred embodiment.

FIG. 5 is a schematic top view of the partial structure of the lens and multiple image sensing elements of the fingerprint recognition module of the present invention in another preferred embodiment.

The reference numbers are as follows:

1 Fingerprint identification module

11 Contact layer

12 light source

13, 23 Image sensing element

14 substrate

15 lenses

131, 231 sensing area

132, 232 shading area

151, 251 opening

B beam

D diameter of opening

G distance between sensing areas

L1 length of sensing area

L2 length of shading area

Detailed ways

The present invention provides a fingerprint identification module to solve known technical problems. The embodiments of the present invention will be further explained below with reference to the relevant drawings. In the drawings, the shape and thickness may be exaggerated for simplicity and convenience. It will be understood that elements not specifically shown in the drawings or described in the specification are forms known to those skilled in the art. Those of ordinary skill in the art can make various changes and modifications based on the contents of the present invention.

Please refer to FIG. 1 , which is a schematic cross-sectional view of a partial structure of a fingerprint identification module in a preferred embodiment of the present invention. The fingerprint recognition module 1 includes a contact layer 11 , a plurality of light sources 12 , a plurality of image sensing elements 13 , a substrate 14 and a lens 15 . The contact layer 11 is exposed outside the fingerprint recognition module 1 and can be in contact with the user's finger F. A plurality of light sources 12 are located under the substrate 14 11 and their function is to generate a plurality of light beams B and can project a plurality of light beams B to Contact layer 11. A plurality of image sensing elements 13 are located under the contact layer 11 , and their function is to receive a plurality of light beams B to generate a fingerprint image corresponding to the finger. The substrate 14 is located under the contact layer 11 and is electrically connected to the plurality of image sensing elements 13, and can carry the plurality of image sensing elements 13 thereon. The substrate 14 can be made of a light-transmitting material, so that the plurality of light beams B can penetrate the substrate 14 . In this preferred embodiment, the light source 12 can use various light-emitting diodes, such as micro-light-emitting diodes, organic light-emitting diodes, etc., and the image sensing element can use a charge-coupled device (CCD) or a contact image sensing element (CIS). .

Please refer to FIG. 1 and FIGS. 2A to 2C at the same time. FIGS. 2A to 2C are schematic top views of the partial structure of the lens of the fingerprint identification module of the present invention in a preferred embodiment. The lens 15 is located between the contact layer 11 and the plurality of image sensing elements 13 , and the lens 15 has a plurality of openings 151 through which the plurality of light beams B can pass and be projected to the plurality of image sensing elements 13 . The fingerprint image generated by the plurality of image sensing elements 13 is generated according to the arrangement of the plurality of openings 151 and the pinhole imaging principle. In this preferred embodiment, the shape of the plurality of openings 151 is circular, as shown in FIG. 2A , and the diameter D of at least one of the plurality of openings 151 is between 7.2 micrometers (Micrometer) and 12 micrometers. time, it is for illustrative purposes only and is not intended to be a limitation. In another preferred embodiment, the shapes of the plurality of openings can be designed in various shapes, such as triangles, as shown in FIG. 2B , or polygons, such as hexagons as shown in FIG. 2C .

Next, the detailed structure of the plurality of image sensing elements 13 will be described. Please refer to FIG. 3 , which is a schematic top view of a partial structure of multiple image sensing elements of the fingerprint recognition module of the present invention in a preferred embodiment. Each image sensing element 13 includes a plurality of sensing areas 131 and a plurality of light-shielding areas 132 , and the multiple sensing areas 131 and the plurality of light-shielding areas 132 are arranged in a 2*2 matrix, as shown in FIG. 3 , which is only an example. use, rather than being limited to this. The function of the sensing area 131 is to receive multiple light beams B to generate corresponding fingerprint images, while the light shielding area 132 is located below the corresponding sensing area 131 and surrounds the sensing area 131 , and its function is to block the multiple light beams B. In this preferred embodiment, the shapes of the sensing area 131 and the light-shielding area 132 are both rectangular, the length L1 of the sensing area 131 is approximately 42.8 microns, and the distance G between each two sensing areas 131 is approximately 7.2 microns, and The length L2 of the light shielding area 132 is approximately 50 microns.

Please refer to FIG. 4 , which is a schematic top view of a partial structure of a lens and a plurality of image sensing elements of the fingerprint recognition module of the present invention in a preferred embodiment. FIG. 4 shows the lens 15 and multiple image sensing elements 13 , where FIG. 4 only shows the partial structure of the fingerprint recognition module 1 . As can be seen from FIG. 4 , a plurality of openings 151 are arranged on the lens 15 in a regular pattern, so that every N openings 151 correspond to one image sensing element 13 . In this preferred embodiment, N is equal to 3, which is for illustration only and is not limited thereto. The advantage of a lens 15 with multiple openings 151 arranged in a regular pattern is that the arrangement of the multiple openings 151 can be adjusted according to the corresponding single image sensing element 13 to obtain better light transmission efficiency, thereby enabling imaging A more optimized fingerprint image is produced, so the identification accuracy of the fingerprint identification module 1 can be improved.

In addition, the present invention also provides lenses of different designs. Please refer to FIG. 5 , which is a schematic top view of a partial structure of a lens and a plurality of image sensing elements of the fingerprint recognition module of the present invention in another preferred embodiment. FIG. 5 shows a lens 25 and a plurality of image sensing elements 23 . The lens 25 has a plurality of openings 251 , and each image sensing element 23 includes a sensing area 231 and a light-shielding area 232 .

As can be seen from FIG. 5 , the plurality of openings 251 are disposed on the lens 25 in an evenly distributed manner, that is, the plurality of openings 251 are irregularly located above the plurality of image sensing elements 23 . In this preferred embodiment, the advantages of the lens 25 of this design are: first, the plurality of openings 251 do not need to be aligned with the image sensing element 23, thereby reducing the difficulty of assembly. Second, the plurality of openings 251 can be designed with a smaller diameter, thereby limiting the incident angle of the plurality of light beams B entering the openings 251, thus improving the identification accuracy of the fingerprint recognition module. Third, the plurality of openings 251 arranged in an evenly distributed manner can alleviate the phenomenon of uneven photosensitivity of the image sensing element 23 .

In summary, according to the special design of the lens in the fingerprint identification module of the present invention, better light transmission efficiency can be obtained, thereby improving the identification accuracy of the fingerprint identification module and solving the problems caused by the known technology.

The above descriptions are only preferred embodiments of the present invention and are not intended to limit the claims of the present invention. Therefore, all other equivalent changes or modifications made without departing from the spirit disclosed in the present invention shall be included in the present invention. within the claims.

Claims (5)

1. A fingerprint identification module, including: A contact layer is exposed outside the fingerprint recognition module and is used to contact a finger; At least one light source to generate at least one light beam, and the at least one light beam is projected to the contact layer; At least one image sensing element is located below the contact layer to receive the at least one light beam and generate a corresponding fingerprint image; and A lens is located between the contact layer and the at least one image sensing element, and the lens has a plurality of openings for allowing the at least one light beam to pass through and be projected to the at least one image sensing element; wherein, the Image sensing components include: At least one sensing area is used to receive the at least one light beam and generate the corresponding fingerprint image; and At least one light-shielding area surrounds the at least one sensing area to block the at least one light beam; wherein the length of the at least one sensing area is 42.8 microns, and the distance between each two sensing areas is 7.2 microns, and the At least one light-blocking area has a length of 50 microns. 2. The fingerprint identification module of claim 1, wherein the diameter of at least one of the plurality of openings is between 7.2 microns and 12 microns. 3. The fingerprint recognition module of claim 1, further comprising a substrate located below the contact layer and electrically connected to the at least one image sensing element; wherein the substrate is light-transmissive, so that the at least one A light beam can penetrate the substrate. 4. The fingerprint identification module of claim 1, wherein a plurality of the openings are arranged on the lens in a regular pattern, such that each N of the plurality of openings corresponds to one of the openings. Image sensing elements, and the N openings are located above the corresponding image sensing elements. 5. The fingerprint recognition module of claim 1, wherein a plurality of the openings are disposed on the lens in an even distribution, and the plurality of openings are evenly located on the at least one image sensing element. above.