Fingerprint identification module, preparation method thereof and electronic device

Abstract

Embodiments of the present application provide a fingerprint identification module, a preparation method thereof and an electronic device. The fingerprint identification module defines a fingerprint identification area and a peripheral area surrounding the fingerprint identification area. The fingerprint identification module comprises a first light shielding layer, an optical sensor, a second light shielding layer, a support portion and a gap portion. The first light shielding layer defines a first through hole. The second light shielding layer defines a second through hole. Each second through hole exposes one optical sensor and is aligned with one first through hole. The support portion is arranged in the peripheral area for bonding the first substrate and the second substrate and maintaining a distance between the first light shielding layer and the second light shielding layer. The gap portion is arranged in the fingerprint identification area. The light signal reflected by the fingerprint is collimated through the first through hole, the gap portion and the second through hole and is received by the optical sensor to realize fingerprint imaging.

Description

Technical Field

[0001] This invention relates to the field of fingerprint recognition technology, and in particular to a fingerprint recognition module, a method for manufacturing a fingerprint recognition module, and an electronic device using the fingerprint recognition module. Background Technology

[0002] Currently, fingerprint recognition modules either employ alternating layers of light-shielding and cover layers to form a collimation structure for fingerprint imaging, or use lenses for fingerprint imaging. However, the structure using alternating layers of light-shielding and cover layers to form a collimation structure requires the sequential fabrication of up to seven to eight film layers, which is very difficult to manufacture. In the structure using lenses for fingerprint imaging, the lenses are even thicker than the collimation structure, and when the fingerprint recognition area is large, the manufacturing of the lenses is also very difficult. Summary of the Invention

[0003] One embodiment of the present invention provides a fingerprint recognition module, which defines a fingerprint recognition area and a peripheral area surrounding the fingerprint recognition area, wherein the fingerprint recognition module includes:

[0004] A first substrate, the first substrate including a transparent first base and a first light-shielding layer located on the first base, the first light-shielding layer defining a plurality of first through holes spaced apart;

[0005] The second substrate includes a transparent second base, a plurality of optical sensors spaced apart on the second base, and a second light-shielding layer located on the side of the optical sensors away from the second base. The second light-shielding layer defines a plurality of spaced second through holes, each second through hole exposing one of the optical sensors and aligning with one of the first through holes. The first light-shielding layer, the optical sensors, and the second light-shielding layer are located between the first base and the second base.

[0006] A support portion, located between the first substrate and the second substrate and disposed in the peripheral area, is used to bond the first substrate and the second substrate and maintain a distance between the first substrate and the second substrate; and

[0007] A gap portion is located between the first substrate and the second substrate and is disposed in the fingerprint recognition area;

[0008] The light signal reflected by the fingerprint is collimated through the first through hole, the gap, and the second through hole and then received by the optical sensor. The optical sensor senses the light signal to achieve fingerprint imaging.

[0009] In the fingerprint recognition module, the first light-shielding layer, the gap, and the second light-shielding layer can form a collimation structure. Thus, a support portion is formed in the peripheral area of ​​the fingerprint recognition module to maintain a certain distance between the first and second substrates, allowing the first and second light-shielding layers to have a certain thickness in the fingerprint recognition area, thereby achieving light collimation. Compared to sequentially stacking multiple layers (up to seven or eight layers) of light-shielding and cover layers to maintain a certain thickness in the collimation structure, this fingerprint recognition module reduces the number of film layers, lowering the manufacturing difficulty. Furthermore, the fabrication of the gap in this fingerprint recognition module is not limited by the area of ​​the fingerprint recognition area, further reducing manufacturing difficulty compared to using lenses for fingerprint imaging.

[0010] An embodiment of the present invention also provides a method for preparing a fingerprint recognition module, comprising:

[0011] A first substrate is provided, the first substrate including a transparent first base and a first light-shielding layer located on the first base, the first light-shielding layer defining a plurality of first through holes spaced apart;

[0012] A second substrate is provided, the second substrate including a transparent second substrate, a plurality of optical sensors spaced apart on the second substrate, and a second light-shielding layer located on the side of the optical sensors away from the second substrate, the second light-shielding layer defining a plurality of spaced second through holes, each second through hole exposing one of the optical sensors; and

[0013] A support portion is formed around the periphery of the first substrate or the second substrate, the support portion bonding the first substrate and the second substrate and maintaining a distance between the first substrate and the second substrate;

[0014] In this configuration, each second through hole is aligned with one first through hole, the first light-shielding layer, the optical sensor, and the second light-shielding layer are located between the first substrate and the second substrate, and the area enclosed by the support portion between the first substrate and the second substrate forms a gap.

[0015] The fabrication method of this fingerprint recognition module involves forming optical spacers in the peripheral area of ​​the fingerprint recognition module to maintain a certain distance between the first and second substrates. This allows the first and second light-shielding layers to have a certain thickness in the fingerprint recognition area, thereby achieving light collimation. Compared to sequentially stacking multiple layers (up to seven or eight layers) of light-shielding and cover layers to maintain a certain thickness in the collimation structure, this fingerprint recognition module reduces the number of film layers, thus lowering the fabrication difficulty. Furthermore, the fabrication of the gaps in this fingerprint recognition module is not limited by the area of ​​the fingerprint recognition area, further reducing the fabrication difficulty compared to using lenses for fingerprint imaging.

[0016] An embodiment of the present invention also provides an electronic device, which includes a display panel and a fingerprint recognition module, wherein the display panel has a display surface, and the fingerprint recognition module is located on the side of the display panel opposite to the display surface, and the fingerprint recognition module is the fingerprint recognition module described above.

[0017] Because the electronic device includes the aforementioned fingerprint recognition module, its manufacturing difficulty is also reduced. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of an electronic device according to an embodiment of the present invention.

[0019] Figure 2 This is a plan view of a fingerprint recognition module according to an embodiment of the present invention.

[0020] Figure 3 for Figure 2 A partial cross-sectional schematic diagram along line AA.

[0021] Figure 4 For application Figure 3 A partial cross-sectional schematic diagram of the electronic device of the fingerprint recognition module shown.

[0022] Figure 5A This is a partial cross-sectional schematic diagram of a fingerprint recognition module according to another embodiment of the present invention.

[0023] Figure 5B This is a partial cross-sectional schematic diagram of a fingerprint recognition module according to another embodiment of the present invention.

[0024] Figure 6 This is a plan view of a fingerprint recognition module according to another embodiment of the present invention.

[0025] Figure 7 This is a flowchart of a fingerprint recognition module preparation method according to an embodiment of the present invention.

[0026] Explanation of main component symbols

[0027] Electronic devices 100

[0028] Display panel 20

[0029] Sensing area SA

[0030] Display surface 22

[0031] Fingerprint recognition module 10

[0032] Fingerprint recognition area FA

[0033] Surrounding Area NA

[0034] First substrate 11

[0035] First base 112

[0036] First light-shielding layer 114

[0037] First through hole 1142

[0038] First opening 1144

[0039] Covering layer 116

[0040] Third light-shielding layer 118

[0041] Third through hole 1182

[0042] Second substrate 12

[0043] Second base 122

[0044] Highlighting Area 1222

[0045] Optical sensor 124

[0046] Second light-shielding layer 126

[0047] Second through hole 1262

[0048] Second opening 1264

[0049] Protective layer 128

[0050] Frame adhesive 13

[0051] Optical spacer 14

[0052] Gap 15

[0053] Chip-on-chip film 16

[0054] Fingerprint recognition chip 162

[0055] Flexible Circuit Board 164

[0056] Support section 17

[0057] The following detailed description, in conjunction with the accompanying drawings, will further illustrate the present invention. Detailed Implementation

[0058] Figure 1 This is a schematic diagram of the structure of an electronic device 100 according to an embodiment of the present invention. Figure 1As shown, the electronic device 100 includes a display panel 20 and a fingerprint recognition module 10 located below the display panel 20. The display panel 20 has a display surface 22, and the fingerprint recognition module 10 is located on the side of the display panel 20 opposite to the display surface 22. It is used to receive light signals reflected back from an external object (such as a finger) through the display panel 20 and convert the received light signals into corresponding electrical signals for fingerprint recognition.

[0059] like Figure 1 As shown, the display panel 20 has a sensing area SA that can be touched by an external object (such as a finger). The fingerprint recognition module 10 is aligned with the sensing area SA. When a finger touches the sensing area SA, the fingerprint recognition module 10 can capture a fingerprint image of the finger to obtain the corresponding fingerprint information.

[0060] In one embodiment, the sensing area SA is at least partially located within the display area of ​​the display panel 20. In other embodiments, the sensing area SA can be extended to the entire display area of ​​the display panel 20. The area of ​​the display panel 20 used to display the image is the display area, and the area outside the display area of ​​the display panel 20 is the non-display area.

[0061] In one embodiment, the display panel 20 can be a self-emissive display panel having self-emissive units (not shown). For example, the display panel 20 can be an organic light-emitting diode (OLED) display panel or a micro light-emitting diode (Micro LED) display panel. Some of the self-emissive units in the display panel 20 can be used as a detection light source for fingerprint detection. When an external object (e.g., a finger) presses on the sensing area SA on the display panel 20, the display panel 20 emits a detection beam towards the finger above the sensing area SA. The detection beam is reflected on the surface of the finger to form emitted light. The detection beam reflected back from the finger is received by the fingerprint recognition module 10 and converted into a corresponding electrical signal to realize fingerprint recognition.

[0062] In one embodiment, the electronic device 100 can be, but is not limited to, consumer electronics, home electronics, automotive electronics, and financial terminal products. Consumer electronics include, for example, mobile phones, tablets, laptops, desktop monitors, and all-in-one computers. Home electronics include, for example, smart door locks and refrigerators. Automotive electronics include, for example, car navigation systems and car DVD players. Financial terminal products include, for example, ATMs and self-service terminals.

[0063] The following combination Figures 2 to 6 This describes the fingerprint recognition module 10 of this embodiment.

[0064] Figure 2 This is a plan view of a fingerprint recognition module 10 according to an embodiment of the present invention. Figure 2 As shown, the fingerprint recognition module 10 defines a fingerprint recognition area FA and a peripheral area NA surrounding the fingerprint recognition area FA. It can be understood that the fingerprint recognition area FA of the fingerprint recognition module 10 corresponds to the sensing area SA of the display panel 20.

[0065] In one embodiment, the fingerprint recognition area FA is generally elliptical, roughly the same shape as a finger. In other embodiments, the fingerprint recognition area FA may also be rectangular, and this is not a limitation.

[0066] Figure 3 for Figure 2 A partial cross-sectional view along line AA. (See attached diagram.) Figure 3 As shown, the fingerprint recognition module 10 includes a first substrate 11 and a second substrate 12 disposed opposite to each other. The first substrate 11 includes a first base 112 and a first light-shielding layer 114 located on the first base 112. The first light-shielding layer 114 defines a plurality of first through holes 1142 spaced apart. The second substrate 12 includes a second base 122, a plurality of optical sensors 124 spaced apart on the second base 122, and a second light-shielding layer 126 located on the side of the optical sensors 124 away from the second base 122. The second light-shielding layer 126 defines a plurality of second through holes 1262 spaced apart. Each second through hole 1262 exposes one of the optical sensors 124 and aligns with one of the first through holes 1142. The first light-shielding layer 114, the optical sensors 124, and the second light-shielding layer 126 are located between the first base 112 and the second base 122.

[0067] In one embodiment, the first through-hole 1142, the second through-hole 1262, and the optical sensor 124 can be arranged in an array.

[0068] like Figure 3 As shown, the fingerprint recognition module 10 includes a support portion 17 and a gap portion 15 located between the first substrate 11 and the second substrate 12. The support portion 17 includes a frame adhesive 13 and an optical spacer 14.

[0069] The frame adhesive 13 is aligned with the peripheral area NA to bond the first substrate 11 and the second substrate 12. An optical spacer 14 is disposed within the frame adhesive 13 to maintain a distance between the first substrate 11 and the second substrate 12. A gap portion 15 is aligned with the fingerprint recognition area FA to collimate the light signal reflected from the finger together with the first light-shielding layer 114 and the second light-shielding layer 126.

[0070] Figure 4 For application Figure 3 A partial cross-sectional schematic diagram of the electronic device 100 of the fingerprint recognition module 10 shown. Figure 4As shown, the fingerprint recognition module 10 is located on the side of the display panel 20 opposite to its display surface 22. Some of the self-emissive units in the display panel 20 emit light as the detection light source for the fingerprint recognition module 10. When a finger touches the sensing area SA (fingerprint recognition area FA) of the display surface 22 of the display panel 20, the light emitted by the self-emissive units in the display panel 20 is incident on the display surface 22 and reflected by the valleys and ridges of the fingerprint. The light signal reflected by the fingerprint is collimated and received by the optical sensor 124. The optical sensor 124 senses the light signal to achieve fingerprint imaging.

[0071] In one embodiment, the optical sensor 124 includes a photodiode that can convert a received light signal (e.g., a difference in light intensity) into a difference signal in an electrical signal, thereby enabling fingerprint recognition and determining an image of the fingerprint.

[0072] Figure 4 In this process, light reflected from a finger passes sequentially through the display panel 20, the first substrate 11, and the gap 15 before being received by the optical sensor 124. Specifically, the light reflected from the finger is blocked at the locations of the first light-shielding layer 114 without the first through-hole 1142 and the second light-shielding layer 126 without the second through-hole 1262. The light reflected from the finger then passes through the first through-hole 1142 (a small hole structure) and the third through-hole 1182 before being imaged on the optical sensor 124. Thus, the collimation structure formed by the first light-shielding layer 114 and the second light-shielding layer 126 defines the fingerprint range that each optical sensor 124 can collect. Figure 4 (L1). At the same time, since the light around the fingerprint range L1 is absorbed by the unperforated areas of the first light-shielding layer 114 and the third light-shielding layer 118, interference light is reduced, thereby improving the accuracy of fingerprint recognition.

[0073] The spacing between adjacent peaks in a typical human fingerprint is approximately 500 to 600 micrometers. That is, the average fingerprint spacing (the distance between a trough and an adjacent peak) is approximately 250 to 300 micrometers. In one embodiment, by adjusting the distance from the display surface 22 to the optical sensor 124 and the sizes of the first through-hole 1142 and the second through-hole 1262, the fingerprint range collected by each optical sensor 124 can be adjusted so that the fingerprint range L1 collected by each optical sensor 124 is 200 to 400 micrometers. If L1 is less than 200 micrometers, the detection light source of the display panel 20 is insufficient. If L1 is greater than 400 micrometers, the fingerprint image resolution is poor, and the fingerprint recognition accuracy is low.

[0074] In one embodiment, the fingerprint ranges acquired by two adjacent optical sensors 124 do not overlap. That is, the image regions corresponding to two adjacent imaging regions do not overlap, thereby improving the signal-to-noise ratio detected by the optical sensors 124.

[0075] In one embodiment, both the first through-hole 1142 and the third through-hole 1182 are circular holes, and their dimensions are equal. The ratio of the diameter of the first through-hole 1142 (i.e., the diameter of the third through-hole 1182) to the distance between the display surface 22 and the optical sensor 124 is approximately 1:7, so that the light reflected by the finger has a better collimation effect. In other embodiments, the first through-hole 1142 and the third through-hole 1182 may also be rectangular or other shapes, and are not limited thereto.

[0076] In one embodiment, both the first substrate 112 and the second substrate 122 are made of transparent materials, such as transparent glass. The first light-shielding layer 114 and the second light-shielding layer 126 are made of opaque materials such as organic black matrix or metal.

[0077] In one embodiment, the material of the gap 15 is air. That is, the gap 15 is an air gap. In the fingerprint recognition module 10, the first light-shielding layer 114, the gap 15 (air gap), and the second light-shielding layer 126 can form a collimation structure. In this way, by forming an optical spacer 14 in the peripheral area NA of the fingerprint recognition module 10 to maintain a certain distance between the first substrate 11 and the second substrate 12, the first light-shielding layer 114 and the second light-shielding layer 126 can have a certain thickness in the fingerprint recognition area FA, thereby achieving light collimation. Compared to the method of sequentially stacking multiple layers (up to seven or eight layers) of light-shielding layers and cover layers to maintain a certain thickness of the collimation structure, this fingerprint recognition module 10 reduces the number of film layers and reduces the manufacturing difficulty. In addition, the manufacturing of the gap 15 (air gap) of this fingerprint recognition module 10 is not limited by the area of ​​the fingerprint recognition area FA, and compared with the method of using a lens for fingerprint imaging, the manufacturing difficulty is also reduced.

[0078] In another embodiment, the gap 15 can be a transparent medium. This transparent medium is, for example, optically clear resin (OCR). That is, in the fingerprint recognition module 10, the first light-shielding layer 114, the gap 15 (transparent medium), and the second light-shielding layer 126 can form a collimation structure. Thus, by forming an optical spacer 14 in the peripheral region NA of the fingerprint recognition module 10 to maintain a certain distance between the first substrate 11 and the second substrate 12, and filling the fingerprint recognition area FA with a transparent medium, a certain thickness can be achieved between the first light-shielding layer 114 and the second light-shielding layer 126 in the fingerprint recognition area FA, thereby achieving light collimation. Similarly, compared to sequentially stacking multiple layers (up to 7 to 8 layers) of light-shielding layers and cover layers 116 to maintain a certain thickness in the collimation structure, this fingerprint recognition module 10 reduces the number of film layers and lowers the manufacturing difficulty. Furthermore, the fabrication of the gap portion 15 (transparent medium) of the fingerprint recognition module 10 is not limited by the area of ​​the fingerprint recognition area FA, which also reduces the manufacturing difficulty compared to using a lens for fingerprint imaging.

[0079] In one embodiment, the first substrate 11 further includes a transparent cover layer 116 located on the side of the first light-shielding layer 114 away from the first substrate 112, and a third light-shielding layer 118 located on the surface of the cover layer 116 away from the first substrate 112. The third light-shielding layer 118 defines a plurality of spaced-apart third through holes 1182. Each of the third through holes 1182 is aligned with one of the first through holes 1142 and one of the second through holes 1262.

[0080] like Figure 4 As shown, along the thickness direction of the first substrate 11, the projection of the third through-hole 1182 on the first substrate 112 completely covers the projection of the first through-hole 1142 on the first substrate 112. The maximum imaging size of the light signal reflected by the fingerprint on the second substrate 122 after collimation through the first through-hole 1142, the third through-hole 1182, and the gap 15 is (…). Figure 4 The distance between two adjacent fingerprint sensors (L2) is less than the distance between L2. That is, by providing a third light-shielding layer 118 between the first light-shielding layer 114 and the second light-shielding layer 126, some of the light reflected by the finger is absorbed, ensuring that the light reflected by the finger in the fingerprint area L3 is received by only one optical sensor 124. In this way, the light signals detected by adjacent optical sensors 124 will not interfere with each other, improving the accuracy of fingerprint recognition.

[0081] In one embodiment, the third light-shielding layer 118 can be made of an opaque material such as an organic black matrix or metal. The cover layer 116 can be made of a transparent resin. In one embodiment, if the third light-shielding layer 118 is made of metal, the second substrate 12 may further include a protective layer 128, which fills the second via 1262 and completely covers the third light-shielding layer 118 to prevent oxidation of the metal in the third light-shielding layer 118. The protective layer 128 can be made of a silicon oxide (SiOx) layer, a silicon nitride (SiNx) layer, or multiple layers thereof.

[0082] In one embodiment, the sizes of the first through-hole 1142, the third through-hole 1182, and the second through-hole 1262 are related to the height of the cover layer 116 and the height of the gap 15. In one embodiment, the diameter of both the first through-hole 1142 and the second through-hole 1262 is 4 micrometers, the height of the cover layer 116 is approximately 6 to 10 micrometers, and the height of the gap 15 is approximately 25 to 35 micrometers, so that the light reflected by the finger has a better collimation effect between the display surface 22 and the optical sensor 124.

[0083] Figure 4 In this design, the optical spacers 14 are spherical. Multiple spherical optical spacers 14 are distributed within the frame adhesive 13. The two ends of each optical spacer 14 are supported on the first substrate 11 and the second substrate 12, respectively, to maintain a certain distance between the first light-shielding layer 114 and the second light-shielding layer 126. The first light-shielding layer 114, the gap 15, and the second light-shielding layer 126 form a collimation structure to collimate the light reflected from the finger. Due to the optical spacers 14, a certain thickness can be maintained between the first light-shielding layer 114 and the second light-shielding layer 126, avoiding the need for sequential fabrication of multiple film layers and reducing manufacturing difficulty. Furthermore, regardless of whether the gap 15 is an air gap or filled with a transparent medium, its fabrication is not limited by the area of ​​the fingerprint recognition area FA, further reducing manufacturing difficulty compared to using lenses for fingerprint imaging.

[0084] In other embodiments, the optical spacers 14 can be columnar optical spacers, with multiple columnar optical spacers 14 spaced apart in the frame adhesive 13. One end of each columnar optical spacer 14 is formed on the first substrate 11, and the other end abuts against the second substrate 12; or one end of each columnar optical spacer 14 is formed on the second substrate 12, and the other end abuts against the first substrate 11. Alternatively, the optical spacers 14 can be closed, elongated barriers surrounding the fingerprint recognition area FA; or, the optical spacers 14 can be open, elongated barriers surrounding the fingerprint recognition area FA. In these cases, the opposite ends of the barriers abut against the first substrate 11 and the second substrate 12, respectively.

[0085] Figure 5A This is a partial cross-sectional schematic diagram of a fingerprint recognition module 10 according to another embodiment of the present invention. Figure 5A In this embodiment, the support portion 17 is a transparent adhesive layer. The first substrate 11 and the second substrate 12 are bonded together via the support portion 17. The support portion 17 not only bonds the first substrate 11 and the second substrate 12 together, but also allows adjustment of the thickness of the support portion 17 to adjust the spacing between the first substrate 11 and the second substrate 12. In one embodiment, the adhesive layer can be a transparent tape, made of materials such as polyethylene terephthalate (PET), but is not limited thereto.

[0086] Figure 5B This is a partial cross-sectional schematic diagram of a fingerprint recognition module 10 according to another embodiment of the present invention. Figure 5B As shown, the first light-shielding layer 114 is further provided with a plurality of first openings 1144 spaced apart. The second light-shielding layer 126 is further provided with a plurality of second openings 1264 spaced apart. Along the thickness direction of the first substrate 11, the projection of each first opening 1144 onto the first substrate 112 and the projection of each second opening 1264 onto the first substrate 112 both fall onto the third light-shielding layer 118. That is, even if the light reflected by the finger passes through the first opening 1144, it can be absorbed by the third light-shielding layer 118 and will not reach the optical sensor 124. Similarly, since the third light-shielding layer 118 can absorb part of the light located above the second openings 1264, mutual interference of light is avoided, and the fingerprint recognition accuracy is improved.

[0087] In one embodiment, a light-shielding material layer can be first formed on the first substrate 112, and then the light-shielding material layer can be patterned to simultaneously form a first opening 1144 and a first through-hole 1142, thereby obtaining a first light-shielding layer 114. Since the first opening 1144 and the first through-hole 1142 can be formed in the same patterning step, the process is simplified. Similarly, the second opening 1264 and the second through-hole 1262 can also be formed in the same patterning step to further simplify the process.

[0088] Please refer to it again. Figure 1 The fingerprint recognition module 10 includes a fingerprint recognition chip 162, and the optical sensor 124 is electrically connected to the fingerprint recognition chip 162. Figure 1 In this process, the flip-chip film 16 includes a flexible circuit board 164 and a fingerprint recognition chip 162 fixed on the flexible circuit board 164. That is, Figure 1In this design, the fingerprint recognition chip 162 employs a ChipOn FPC (COF) packaging method. After the second substrate 12 is bonded to the first substrate 11 with adhesive 13, the second substrate 122 has a protruding region 1222 extending beyond the first substrate 11. The flip-chip film 16 is located in this protruding region 1222.

[0089] In another embodiment, the fingerprint recognition chip 162 employs a chip-on-glass (COG) packaging method. For example... Figure 6 As shown, the fingerprint recognition chip 162 is fixed on the second substrate 122 and then led out to the flexible circuit board 164 through leads (not shown).

[0090] Figure 7 This is a flowchart illustrating a method for fabricating a fingerprint recognition module 10 according to an embodiment of the present invention. Figure 7 As shown, the preparation method generally includes the following steps.

[0091] Step S1: Provide the first substrate 11.

[0092] In one embodiment, the step of providing the first substrate 11 includes providing a transparent first substrate 112, forming a light-shielding material layer (not shown) on the first substrate 112, and patterning the light-shielding material layer to form a plurality of spaced first through holes 1142 to obtain a first light-shielding layer 114.

[0093] In another embodiment, the step of patterning the light-shielding material layer further forms a plurality of spaced first openings 1144, each first opening 1144 being located between two adjacent first through holes 1142.

[0094] In another embodiment, the step of providing the first substrate 11 further includes forming a cover layer 116 on the side of the first light-shielding layer 114 away from the first substrate 112, forming a light-shielding material layer (not shown) on the side of the cover layer 116 away from the first substrate 112, and patterning the light-shielding material layer to form a plurality of spaced third through holes 1182 to obtain a third light-shielding layer 118.

[0095] In one embodiment, the first substrate 112 is made of glass, and the first light-shielding layer 114 and the third light-shielding layer 118 are made of opaque materials such as black matrix or metal.

[0096] Step S2: Provide a second substrate 12.

[0097] In one embodiment, the step of providing the second substrate 12 includes providing a transparent second substrate 122, forming a plurality of spaced-apart optical sensors 124 on the second substrate 122, forming a light-shielding material layer (not shown) on the side of the optical sensors 124 away from the second substrate 122, and patterning the light-shielding material layer to form a plurality of spaced-apart second vias 1262. Each second via 1262 exposes one of the optical sensors 124, thereby obtaining a second light-shielding layer 126.

[0098] In one embodiment, the material of the second substrate 122 is glass, and the material of the second light-shielding layer 126 is an opaque material such as black matrix or metal.

[0099] Step S3: A support portion 17 is formed around the periphery of the first substrate 11 or the second substrate 12. The support portion 17 adheres to the first substrate 11 and the second substrate 12, and maintains a distance between the first substrate 11 and the second substrate 12.

[0100] In one embodiment, the support portion 17 is a transparent adhesive layer. In step S3, the first substrate 11 and the second substrate 12 can be attached together using transparent tape (e.g., PET) of the required thickness.

[0101] In another embodiment, the support portion 17 includes a frame adhesive 13 and an optical spacer 14. Step S3 includes forming the frame adhesive 13 and the optical spacer 14 around the periphery of the first substrate 11 or the second substrate 12. The optical spacer 14 is located within the frame adhesive 13.

[0102] In one embodiment, the optical spacer 14 is a spherical optical spacer. A frame adhesive 13 is formed around the periphery of the first substrate 11 or the second substrate 12, and then the optical spacer 14 is dispersed within the frame adhesive 13.

[0103] In another embodiment, the optical spacer 14 is a columnar optical spacer. The columnar optical spacer 14 can be formed first on the periphery of the first substrate 11 or the second substrate 12, and then the frame adhesive 13 is applied so that the optical spacer 14 is located within the frame adhesive 13.

[0104] In another embodiment, the optical spacer 14 is a long strip-shaped barrier. The long strip-shaped barrier can be formed first on the periphery of the first substrate 11 or the second substrate 12, and then the frame adhesive 13 is applied so that the optical spacer 14 is located within the frame adhesive 13.

[0105] It should be noted that the steps for forming the optical spacer 14 and the frame adhesive 13 are not limited to these steps, and can be borrowed from the manufacturing steps of the optical spacer and frame adhesive in the liquid crystal display panel.

[0106] In this configuration, after the first substrate 11 and the second substrate 12 are bonded together, each second through hole 1262 is aligned with one first through hole 1142. The first light-shielding layer 114, the optical sensor 124, and the second light-shielding layer 126 are located between the first substrate 112 and the second substrate 122. The optical spacer 14 maintains a distance between the first substrate 11 and the second substrate 12, and the area enclosed by the frame adhesive 13 between the first substrate 11 and the second substrate 12 forms a gap 15.

[0107] In one embodiment, the material of the gap 15 is a transparent medium. Step S3 further includes filling the area enclosed by the frame adhesive 13 with the transparent medium. The transparent medium can be a transparent resin.

[0108] In one embodiment, the method further includes providing a fingerprint recognition chip 162, wherein the fingerprint recognition chip 162 is disposed on the second substrate 122 by means of a flexible circuit board carrier chip packaging method or a glass carrier chip packaging method.

[0109] The fingerprint recognition module 10 can be fabricated using the same method as a liquid crystal display panel. By placing an optical spacer 14 between the first substrate 11 and the second substrate 12, a certain thickness can be maintained between the first light-shielding layer 114 and the second light-shielding layer 126, avoiding the need for sequential fabrication of multiple film layers and reducing manufacturing difficulty. Furthermore, regardless of whether the gap 15 is an air gap or filled with a transparent medium, its fabrication is not limited by the area of ​​the fingerprint recognition area FA, further reducing manufacturing difficulty compared to using a lens for fingerprint imaging.

[0110] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A fingerprint recognition module, comprising a fingerprint recognition area and a peripheral area surrounding the fingerprint recognition area, characterized in that, The fingerprint recognition module is used to be disposed on the side of a display panel opposite to the display surface, and the fingerprint recognition module includes: A first substrate, the first substrate including a transparent first base and a first light-shielding layer located on the first base, the first light-shielding layer defining a plurality of first through holes spaced apart; The second substrate includes a transparent second base, a plurality of optical sensors spaced apart on the second base, and a second light-shielding layer located on the side of the optical sensors away from the second base. The second light-shielding layer defines a plurality of spaced second through holes, each second through hole exposing one of the optical sensors and aligning with one of the first through holes. The first light-shielding layer, the optical sensors, and the second light-shielding layer are located between the first base and the second base. A support portion is located between the first substrate and the second substrate, which adheres the first substrate and the second substrate and maintains a distance between the first substrate and the second substrate. The support portion is only disposed in the peripheral area and together with the first substrate and the second substrate, forms an air gap in the fingerprint recognition area. The light signal reflected by the fingerprint is collimated through the first through hole, the air gap, and the second through hole and then received by the optical sensor. The optical sensor senses the light signal to achieve fingerprint imaging.

2. The fingerprint recognition module as described in claim 1, characterized in that, The support portion includes a frame adhesive and an optical spacer located within the frame adhesive, or the support portion is a transparent adhesive layer.

3. The fingerprint recognition module as described in claim 1, characterized in that, Each of the optical sensors acquires fingerprints ranging from 200 micrometers to 400 micrometers.

4. The fingerprint recognition module as described in claim 1, characterized in that, The fingerprint ranges collected by two adjacent optical sensors do not overlap.

5. The fingerprint recognition module as described in claim 1, characterized in that, The first substrate further includes a transparent cover layer located on the side of the first light-shielding layer away from the first substrate, and a third light-shielding layer located on the surface of the cover layer away from the first substrate; The third light-shielding layer is defined with a plurality of third through holes spaced apart, each of the third through holes being aligned with a first through hole and a second through hole; The maximum imaging size of the light signal reflected by the fingerprint on the second substrate after collimation through the first through hole, the third through hole and the air gap is smaller than the distance between two adjacent optical sensors.

6. The fingerprint recognition module as described in claim 1, characterized in that, The fingerprint recognition module also includes a fingerprint recognition chip, and the optical sensor is electrically connected to the fingerprint recognition chip. The fingerprint recognition chip is packaged using a flip-chip method or a glass-based chip packaging method.

7. A method for manufacturing a fingerprint recognition module, characterized in that, include: A first substrate is provided, the first substrate including a transparent first base and a first light-shielding layer located on the first base, the first light-shielding layer defining a plurality of first through holes spaced apart; A second substrate is provided, the second substrate including a transparent second substrate, a plurality of optical sensors spaced apart on the second substrate, and a second light-shielding layer located on the side of the optical sensors away from the second substrate, the second light-shielding layer defining a plurality of spaced second through holes, each second through hole exposing one of the optical sensors; as well as A support portion is formed around the periphery of the first substrate or the second substrate, the support portion bonding the first substrate and the second substrate and maintaining a distance between the first substrate and the second substrate; Each of the second through holes is aligned with one of the first through holes. The first light-shielding layer, the optical sensor, and the second light-shielding layer are located between the first substrate and the second substrate. An air gap is formed in the area enclosed by the support portion between the first substrate and the second substrate.

8. The method for preparing a fingerprint recognition module as described in claim 7, characterized in that, The support portion includes a frame adhesive and an optical spacer located within the frame adhesive, or the support portion is a transparent adhesive layer.

9. An electronic device comprising a display panel and a fingerprint recognition module, characterized in that, The display panel has a display surface, and the fingerprint recognition module is located on the side of the display panel opposite to the display surface. The fingerprint recognition module is the fingerprint recognition module as described in any one of claims 1 to 6.

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