WO2020082369A1

WO2020082369A1 - Under-screen biometric feature recognition apparatus and electronic device

Info

Publication number: WO2020082369A1
Application number: PCT/CN2018/112212
Authority: WO
Inventors: 许炜添
Original assignee: 深圳市汇顶科技股份有限公司
Priority date: 2018-10-26
Filing date: 2018-10-26
Publication date: 2020-04-30
Also published as: CN109496311A

Abstract

An under-screen biometric feature recognition apparatus and an electronic device. The under-screen biometric feature recognition apparatus comprises: a lens (210) provided below a display screen, so as to receive an optical signal returned from above the display screen by a finger, the optical signal being used to detect biometric feature information about the finger; a lens barrel (220), the lens (210) being fixed within the lens barrel (220); an optical filter (230) located below the lens (210); and a sensing chip (240) provided below the lens barrel (220), the sensing chip (240) being used for imaging on the basis of the optical signal passing through the lens (210), and a distance between a photosensitive surface of the sensing chip (240) and an imaging surface of the lens (210) being greater than or equal to a preset value. The present invention is able to improve the efficiency of under-screen biometric feature recognition.

Description

Under-screen biometric identification device and electronic equipment

Technical field

The present application relates to the field of biometrics recognition, and more specifically, to an off-screen biometrics recognition device and electronic equipment.

Background technique

With the rapid development of the electronic equipment industry, especially the rapid development of mobile communication devices (for example, mobile phones), biometrics is gaining more and more attention, and more convenient off-screen biometrics, such as off-screen fingerprint recognition technology Practicalization has become a public demand.

At present, under-screen optical fingerprint recognition technology mainly includes under-screen optical fingerprint recognition technology based on periodic micro-hole arrays and under-screen optical fingerprint recognition technology based on integrated microlens. The former optical fingerprint recognition technology is easily affected by moiré fringes, and the optical fingerprint recognition module needs to be attached under the OLED screen, and the process is complicated. The fingerprint identification module of the latter type of under-screen optical fingerprint identification technology is integrated. In the mass production process, the precision requirement for the entire optical fingerprint identification module is very high. The general processing technology cannot meet the actual demand. Due to the existence of the above-mentioned problems, the efficiency of under-screen biometrics recognition is affected.

Therefore, how to improve the efficiency of off-screen biometrics recognition has become an urgent technical problem to be solved.

Summary of the invention

Provided is an off-screen biometric identification device and electronic equipment, which can improve the efficiency of off-screen biometric identification.

In a first aspect, an off-screen biometric identification device is provided, including:

The lens is arranged below the display screen to receive the light signal returned from the human finger above the display screen, the light signal is used to detect the biometric information of the finger;

Lens barrel, the lens is fixed in the lens barrel;

An optical filter, the optical filter is located below the lens;

A sensor chip, the sensor chip is disposed below the lens barrel, the sensor chip is used for imaging based on the optical signal passing through the lens, wherein the photosensitive surface of the sensor chip and the The distance between the imaging surfaces of the lens is greater than or equal to a preset value.

In some possible implementations, the optical filter is fixed on the side wall in the lens barrel by direct contact.

In some possible implementation manners, the optical filter is formed with a first dispensing structure near the lens barrel and the lens, and the optical filter is dispensed in the first dispensing structure Fixed on the side wall in the lens barrel.

In some possible implementations, the optical filter is fixed on the side wall in the lens barrel by dispensing in a gap contacting the lens barrel, or the optical filter is passed through The way of dispensing glue at the edge of the lower surface is fixed on the side wall in the lens barrel.

In some possible implementations, the under-screen biometric identification device further includes a filter holder, the optical filter is fixed on the filter holder, and the filter holder is fixed on the filter holder by direct contact On the side wall inside the lens barrel.

In some possible implementation manners, a first step structure is formed on the upper surface of the filter holder extending in the axis direction of the lens barrel, and the optical filter is fixed in the first step structure.

In some possible implementation manners, the lower surface of the filter holder extends toward the side wall of the lens barrel to form an arc-shaped structure, and the filter holder is fixed on the arc-shaped structure by dispensing On the side wall in the lens barrel.

In some possible implementation manners, the filter holder is formed with a second dispensing structure near the lens barrel and the lens, and the filter holder is dispensed in the second dispensing structure Fixed on the side wall in the lens barrel.

In some possible implementations, the filter holder is fixed on the side wall in the lens barrel by dispensing glue in a gap contacting the lens barrel.

In some possible implementations, the optical filter completely covers the bottom of the lens.

In some possible implementation manners, the optical filter is an infrared cut-off optical filter and / or a blue cut-off optical filter.

In some possible implementations, the imaging surface of the lens is located above or below the photosensitive surface of the sensor chip.

In some possible implementations, the preset value is 10 μm.

In some possible implementations, the lens includes a lens composed of at least one aspherical injection lens.

In some possible implementations, the lens is a macro lens.

In some possible implementation manners, the focal length of the macro lens is 0.4-1.8 mm.

In some possible implementation manners, the off-screen biometric identification device further includes:

A lens holder, the lens holder is used to support the lens barrel.

In some possible implementation manners, a third dispensing structure is formed on the upper surface of the lens holder extending downwards near the peripheral region of the lens barrel, and between the lens holder and the lens barrel The third dispensing structure is fixed by means of dispensing.

In some possible implementations, the lens holder and the lens barrel are an integral structure.

In some possible implementation manners, the lens barrel is formed with a second step structure on an outer wall away from the barrel opening, and the second step structure is used to fix the lens barrel.

In some possible implementations, the lower surface of the lens holder extends downward at an edge away from the lens barrel to form a first fixing structure, and the first fixing structure is used to fix the lens holder.

In some possible implementation manners, the upper surface of the lens barrel extends inward at the barrel opening to form a first convex structure, and the first convex structure is used to fix the lens.

In some possible implementations, the upper surface of the lens barrel is chamfered at the mouth of the barrel to form an oblique angle, so that the inner diameter of the lens barrel at the upper surface is greater than the first protrusion of the lens barrel The inner diameter of the structure.

In some possible implementation manners, a third step structure is formed under the first convex structure on the inner surface of the lens barrel, and the lens passes through the first convex structure and the third step structure It is fixed in the lens barrel.

In some possible implementations, the lens barrel is fixed on the upper surface of the sensor chip.

In some possible implementations, the lens barrel is fixed on the upper surface of the sensor chip by fixing glue.

In some possible implementation manners, the fixing glue has at least one of the following characteristics: impervious to visible light, having a thickness of 0.02 mm to 0.10 mm, a viscosity> 20000 mPas, and a curing shrinkage rate <3%.

A flexible printed circuit board, the sensor chip is fixed on the upper surface of the flexible printed circuit board, and the lower surface of the lens holder and the upper surface of the flexible printed circuit board are on the edge of the sensor chip The area is fixedly connected.

In some possible implementation manners, the lens holder is sealed and adhered by means of fixing glue on the flexible printed circuit board.

In some possible implementations, the mirror base is formed with an exhaust hole, and the exhaust hole is used to adjust the air pressure intensity of the internal space formed by the mirror base and the flexible printed circuit board.

In some possible implementation manners, the sensor chip is fixed on the upper surface of the flexible printed circuit board through die bonding glue, and the sensor chip is electrically connected to the flexible printed circuit board through a bonding wire.

A fixing frame, the lens base is fixed below the display screen through the fixing frame, and the distance between the upper surface of the display screen and the optical center of the lens satisfies imaging conditions.

In some possible implementation manners, the fixing frame and the lens holder are installed and fixed by at least one of the following installation methods: screw installation fixing method, glue material fixing method, welding fixing method, and coupling fixing method .

In some possible implementation manners, the under-screen biometric identification device is applied to an electronic device, the fixing frame is a middle frame of the electronic device, and the middle frame is used to support the display screen.

In some possible implementations, the middle frame is formed with an opening, the lens barrel is at least partially accommodated in the opening, and there is a gap between the outside of the lens barrel and the inside of the opening.

In some possible implementation manners, the upper surface of the middle frame is chamfered at the edge of the opening to form a bevel, the bevel angle makes the opening width of the upper surface of the middle frame larger than the middle frame The opening width of the lower surface.

In a second aspect, an electronic device is provided, including:

The off-screen biometric identification device described in the first aspect.

In some possible implementation manners, the electronic device further includes:

A display screen, the under-screen biometric identification device is disposed below the display screen, and the distance between the upper surface of the display screen and the optical center of the lens in the under-screen biometric identification device satisfies a predetermined Imaging conditions, wherein the biometric collection area of the under-screen biometric identification device is at least partially located in the display area of the display screen.

In some possible implementations, the electronic device further includes: a middle frame, and the under-screen biometric identification device is assembled under the display screen through the middle frame, so that the under-screen biometric identification device There is a gap with the display screen.

In some possible implementations, the electronic device further includes a screen assembly flexible circuit board, the screen assembly flexible circuit board is located between the display screen and the middle frame, and the screen assembly flexible circuit board is The middle frames are sealed and fixed by at least one side of compressible foam glued on the back.

In some possible implementations, if the foam is glued on both sides, the adhesive of the foam to the flexible circuit board of the screen assembly is weaker than the adhesive of the foam to the middle frame The stickiness of the glue.

In some possible implementations, the compression ratio of the foam is> 50%.

On the one hand, in the embodiment of the present application, the optical filter is provided in the lens barrel, and at the same time, by controlling the assembly size of the lens barrel, the distance between the photosensitive surface of the sensor chip and the imaging surface of the lens is greater than or equal to a preset value That is, the photosensitive surface of the sensor chip can be out of focus, thereby achieving the desired optical imaging, thereby reducing the requirements for processing technology, and also solving the batch yield problem of the integrated module in the production and assembly process The problem that the optimal focal length of the integrated module cannot be accurately aligned, thereby improving the efficiency of biometric recognition under the screen.

On the other hand, to avoid sticking the optical fingerprint recognition module to the lower surface of the display screen, it is only necessary to set the under-screen biometric identification device under the display screen, specifically, to set the lens under the display screen, Effectively simplifies the installation process of the under-screen biometric identification device, improves the batch yield during the installation of the under-screen biometric identification device, and reduces the damage rate during the replacement of the under-screen biometric identification device, thereby Effectively reduce costs.

BRIEF DESCRIPTION

FIG. 1 is a schematic plan view of an electronic device to which this application can be applied.

Fig. 2 is a schematic partial cross-sectional view of the electronic device shown in Fig. 1 along A-A '.

FIG. 3 is a schematic diagram of a partial cross-sectional structure of the under-screen biometric identification device provided by the present application.

4 is a schematic diagram of the imaging surface of the lens in the embodiment of the present application above the photosensitive surface of the sensor chip.

FIG. 5 is a schematic diagram of the imaging surface of the lens in the embodiment of the present application below the photosensitive surface of the sensor chip.

6 is a schematic diagram of a partial cross-sectional structure of an under-screen biometric identification device provided by the present application.

7 is a schematic diagram of a partial cross-sectional structure of another off-screen biometric identification device provided by the present application.

8 is a schematic diagram of a partial cross-sectional structure of yet another off-screen biometric identification device provided by the present application.

9 is a schematic diagram of a partial cross-sectional structure of a flexible printed circuit board in an under-screen biometric identification device according to an embodiment of the present application.

FIG. 10 is a schematic structural diagram of a fixing frame in an under-screen biometrics identification device according to an embodiment of the present application.

FIG. 11 is a schematic diagram of fixing an under-screen biometric identification device under a display screen through a middle frame provided by an embodiment of the present application.

FIG. 12 is a schematic diagram of the assembly process of the off-screen biometric identification device according to an embodiment of the present application.

detailed description

The technical solutions in the embodiments of the present application will be described below with reference to the drawings.

As electronic devices enter the era of full screens, the fingerprint collection area on the front of electronic devices is squeezed by full screens. Therefore, under-display (Under-display or Under-screen) fingerprint recognition technology has attracted more and more attention. The off-screen fingerprint recognition technology refers to installing the fingerprint recognition module (such as the fingerprint recognition module) under the display screen, so as to realize the fingerprint recognition operation in the display area of the display screen, without the need for other than the display area on the front of the electronic device Area setting fingerprint collection area.

The fingerprint recognition technology under the optical screen uses the light returned from the top surface of the display component of the device to perform fingerprint sensing and other sensing operations. The returned light carries information of an object (such as a finger) that is in contact with the top surface. By collecting and detecting the returned light, a specific optical sensor module located below the display screen is realized. The design of the optical sensor module may be to achieve the desired optical imaging by appropriately configuring the optical elements for collecting and detecting the returned light.

It should be understood that the technical solutions of the embodiments of the present application may be applied to various electronic devices, such as smart phones, notebook computers, tablet computers, game devices, and other portable or mobile computing devices, as well as electronic databases, automobiles, and bank automated teller machines (Automated Teller Machine) , ATM) and other electronic devices, but this embodiment of the present application is not limited thereto.

1 and 2 show a schematic diagram of an electronic device 100 to which the fingerprint identification device according to an embodiment of the present application can be applied, wherein FIG. 1 is a schematic front view of the electronic device 100, and FIG. 2 is along the electronic device 100 shown in FIG. AA 'partial cross-sectional structure diagram.

As shown in FIG. 1 and FIG. 2, the electronic device 100 includes a display screen 120 and an optical fingerprint recognition device (hereinafter simply referred to as a fingerprint recognition device) 130, wherein the optical fingerprint recognition device 130 has one or more sensors An array, the sensing array is at least disposed in a partial area below the display screen 120, so that the fingerprint collection area (or sensing area) 103 of the optical fingerprint recognition device 130 is at least partially located in the display area 102 of the display screen 120 .

It should be understood that the area of the fingerprint collection area 103 may be different from the area of the sensing array of the optical fingerprint recognition device 130, for example, through optical path design such as lens imaging, reflective folding optical path design, or other optical path design such as light gathering or reflection , The area of the fingerprint collection area 103 of the optical fingerprint identification device 130 may be larger than the area of the sensing array of the optical fingerprint identification device 130. In other alternative implementations, if the light path is guided by, for example, light collimation, the fingerprint collection area 103 of the optical fingerprint identification device 130 may also be designed to be consistent with the area of the sensing array of the optical fingerprint identification device 130.

As shown in FIG. 1, the fingerprint collection area 103 is located in the display area 102 of the display screen 120, therefore, when the user needs to unlock the electronic device or other fingerprint verification, he only needs to press his finger In the fingerprint collection area 103 located in the display screen 120, fingerprint input can be realized. Since fingerprint detection can be implemented within the screen, the electronic device 100 adopting the above structure does not require a special reserved space on the front to set fingerprint keys (such as the Home key), so that a full-screen solution can be adopted, that is, the display area of the display screen 120 102 can be basically extended to the front of the entire electronic device 100.

As an embodiment, the display screen 120 may be a self-luminous display screen that uses a self-luminous display unit as a display pixel, such as an organic light-emitting diode (Organic Light-Emitting Diode, OLED) display screen or a micro light-emitting diode (Micro -LED) display screen. Taking an OLED display screen as an example, the optical fingerprint recognition device 130 may use the OLED display unit (ie, OLED light source) of the OLED display screen 120 located in the fingerprint recognition area 103 as an excitation light source for optical fingerprint detection.

In other embodiments, the optical fingerprint recognition device 130 may also use an internal light source or an external light source to provide an optical signal for fingerprint detection. In this case, the optical fingerprint recognition device 130 may be applicable to non-self-luminous display screens, such as liquid crystal display screens or other passive light-emitting display screens. Taking an LCD screen with a backlight module and a liquid crystal panel as an example, in order to support under-screen fingerprint detection of the LCD screen, the optical fingerprint system of the electronic device 100 may further include an excitation light source for optical fingerprint detection. The excitation light source may specifically be an infrared light source or a light source of a non-visible light of a specific wavelength, which may be provided under the backlight module of the liquid crystal display or the edge area under the protective cover of the electronic device 100, and the The optical fingerprint recognition device 130 may be disposed under the edge area of the liquid crystal panel or the protective cover and guided by the optical path so that the fingerprint detection light can reach the optical fingerprint recognition device 130; or, the optical fingerprint recognition device 130 may also be disposed at the The backlight module is below, and the backlight module allows the fingerprint detection light to pass through the liquid crystal panel and the backlight module and reach the optics through openings or other optical design of the film layers such as the diffusion sheet, the brightness enhancement sheet, the reflection sheet, etc. Fingerprint recognition device 130.

In addition, the sensing array of the optical fingerprint recognition device 130 is specifically a photodetector array, which includes a plurality of photodetectors distributed in an array, and the photodetectors can be used as the optical sensing unit as described above . When a finger touches, presses, or approaches (for ease of description, this application is collectively referred to as touch) on the fingerprint recognition area 103, the light emitted by the display unit of the fingerprint recognition area 103 is reflected on the fingerprint on the finger surface and forms reflected light The reflected light of the ridges and valleys of the finger fingerprint is different. The reflected light is received from the display screen 120 and received by the photodetector array and converted into a corresponding electrical signal, that is, a fingerprint detection signal. Based on the fingerprint detection signal, fingerprint image data can be obtained, and fingerprint matching verification can be further performed, thereby implementing an optical fingerprint recognition function in the electronic device 100.

It should be understood that, in a specific implementation, the electronic device 100 further includes a transparent protective cover 110, and the cover 110 may be specifically a transparent cover, such as a glass cover or a sapphire cover, which is located on the display screen 120 above and covering the front of the electronic device 100. Therefore, in the embodiments of the present application, the so-called finger touch, pressing or approaching on the display screen 120 actually refers to the finger touching, pressing or approaching the cover plate 110 above the display screen 120 or covering the cover plate 110 Surface of the protective layer. In addition, the electronic device 100 may further include a touch sensor, and the touch sensor may be specifically a touch panel, which may be provided on the surface of the display screen 120, or may be partially or wholly integrated into the display screen 120, namely The display screen 120 is specifically a touch display screen.

As an optional implementation manner, as shown in FIG. 2, the optical fingerprint recognition device 130 includes an optical detection unit 134 and an optical component 132. The optical detection unit 134 includes the sensor array and the sensor array. The read circuit and other auxiliary circuits that are sexually connected can be fabricated on a chip through a semiconductor process; that is, the optical detection unit 134 can be fabricated on an optical imaging chip, an image sensor chip, or an optical sensor chip. The optical component 132 may be disposed above the sensing array of the optical detection unit 134, which may specifically include a filter, a light path guiding structure, and other optical elements, and the filter may be used to filter out Ambient light through the finger, and the light path guiding structure is mainly used to guide the light path such as collimating, modulating or converging the downward propagating light so as to guide the reflected light reflected from the surface of the finger to the sensing array Optical inspection.

In a specific implementation, the optical component 132 may be packaged with the optical detection unit 134 in the same optical fingerprint chip, or the optical component 132 may be disposed outside the chip where the optical detection unit 134 is located, such as The optical component 132 is attached to the chip, or a part of the optical component 132 is integrated into the chip. Among them, the optical path guiding structure of the optical component 132 has various implementation solutions, for example, it may be specifically an optical path modulator or an optical path collimator made of a semiconductor silicon chip or other substrate, which has multiple optical path modulation units or A collimating unit, the optical path modulation unit or the collimating unit may be specifically a micro-hole array. Alternatively, the light guide layer may also be an optical lens (Lens) layer, which has one or more lens units, such as a lens group composed of one or more aspheric lenses. After the reflected light reflected from the finger is collimated or condensed by the micro-hole array or the lens unit, and received by the optical sensing unit below it, the sensing array can detect the fingerprint image of the finger .

A circuit board 140, such as a flexible printed circuit (FPC), may also be provided under the optical fingerprint recognition device 130, and the optical fingerprint recognition device 130 may be soldered to the circuit board 140 through pads, for example. In addition, the circuit board 140 realizes electrical interconnection and signal transmission with other peripheral circuits or other elements of the electronic device 100. For example, the optical fingerprint recognition device 130 may receive the control signal of the processing unit of the electronic device 100 through the circuit board 140, and may also output the fingerprint detection signal to the electronic device through the circuit board 140 100 processing unit or control unit.

As mentioned above, in one implementation, the optical fingerprint recognition device 130 may use a periodic micro-hole array to transmit light to the sensing array, which requires the optical fingerprint recognition module to be attached under the OLED screen, which is complicated and costly high. In another implementation, the optical fingerprint recognition device 130 may use an integrated microlens to transmit light to the sensing array. The integrated microlens refers to designing the microlens and the sensing array as a whole to form a whole Type module, because the integrated module requires very high precision in the mass production process, the general processing technology can not meet the actual demand.

In order to solve the above technical problems, the embodiments of the present application provide an improved technical solution. Specifically, an off-screen biometrics recognition device in defocused state (corresponding to the optical fingerprint recognition device 130 in FIG. 2) is proposed. More specifically, the under-screen biometric identification device may include a lens, a lens barrel, an optical filter, and a sensor chip, the lens is disposed below the display screen, and the lens is used to receive An optical signal formed by the reflection of a human finger, the optical signal is used to detect the biometric information of the finger; the lens is fixed in the lens barrel; the optical filter is fixed in the lens barrel, and the The optical filter is located under the lens; the sensor chip is disposed under the lens barrel, the sensor chip is used for imaging based on the optical signal passing through the lens, wherein the sensor chip The distance between the photosensitive surface of the lens and the imaging surface of the lens is greater than or equal to a preset value.

It should be noted that the distance between the photosensitive surface of the sensor chip and the imaging surface of the lens is greater than or equal to a preset value, and it can also be understood that the photosensitive surface of the sensor chip is in a defocused state.

It should be understood that in the embodiment of the present application, in addition to the optical signal formed by the reflection of the human finger from above the display screen, the lens will also receive the optical signal formed by the reflection of the display screen's own structure (eg, internal circuit). The photosensitive surface of the chip is on the same plane as the imaging surface of the lens. The light signal reflected by the structure of the display screen will affect the biological information collection of the finger. Therefore, the distance between the photosensitive surface of the sensor chip and the imaging surface of the lens is greater than Or it is equal to the preset value, that is, the photosensitive surface of the sensor chip is out of focus with respect to the lens. At this time, the light signal reflected by the structure of the display screen will pass from above the display screen when it reaches the photosensitive surface of the sensor chip. The optical signal formed by the reflection of the human finger greatly reduces the impact. When the preset value is 10 μm, the impact is negligible.

It should be noted that in some scenarios, the lens in the embodiment of the present application needs to be configured to be more precise and smaller in size than the assembly process of the front camera used for taking photos Meet the requirements of precise focusing of the optical fingerprint under the screen.

The technical solution of the embodiment of the present application, compared with the previous implementation (using a periodic micro-hole array to transmit light to the sensing array), avoids attaching the optical fingerprint recognition module to the lower surface of the display screen, and only needs to The biometric identification device (corresponding to the optical fingerprint identification device 130 in FIG. 2) may be provided below the display screen. For example, setting the lens under the display screen effectively simplifies the under-screen biometric identification device The installation process improves the batch yield during the installation of the under-screen biometric identification device, reduces the damage rate during the replacement of the under-screen biometric identification device, and effectively reduces the cost.

Compared with the latter implementation method (using an integrated microlens to transmit light to the sensing array), the technical solution of the embodiment of the present application is provided by setting between the photosensitive surface of the sensor chip and the imaging surface of the lens The distance is greater than or equal to the preset value to achieve the desired optical imaging, thereby reducing the requirements for processing technology, effectively solving the problem of excessive precision requirements for the integrated module in mass production, and thus also solving the integrated module The batch yield problem in the production and assembly process solves the problem that the optimal focal length of the integrated module cannot be accurately aligned, thereby improving the efficiency of biometric recognition under the screen.

The display screen used in the technical solutions of the embodiments of the present application may be an OLED screen, a soft screen, or a hard screen. The following uses the OLED screen as an example to elaborate in detail. Under the OLED screen, there is a layer of shading layer, screen protection foam, optical glue, flexible circuit board of the screen assembly, etc. By opening each layer, the OLED screen will leak light downward. When the finger is placed on the bright screen OLED, the finger will reflect the light emitted by the OLED screen, and this reflected light will penetrate the OLED screen until it is below the OLED. It should be noted that the fingerprint is a diffuse reflector, and its reflected light exists in all directions. Put a microporous lens under the OLED screen to collect the light leaking above the fingerprint screen. This part of the light contains the fingerprint signal and the internal structure signal of the OLED screen. The infrared component in the leaked light is filtered through the infrared cut-off optical filter, and the fingerprint image filtered out of the red light is received through the sensor chip. By adjusting the imaging distance of the lens within a tiny defocus range, the imaging of the internal structure of the OLED screen is blurred, but the fingerprint imaging is not affected.

The off-screen biometric identification device 200 in the embodiment of the present application will be described clearly with reference to FIGS. 3 to 11 below. It should be noted that, for ease of description, in the embodiments of the present application, the same reference numerals denote the same components, and for simplicity, in different embodiments, detailed descriptions of the same components are omitted.

3 to 8 show schematic diagrams of the off-screen biometric identification device 200, wherein FIG. 3 is a schematic diagram of a partial cross-sectional structure of the off-screen biometric identification device 200. 4 is a schematic diagram of the imaging surface of the lens 210 above the photosensitive surface of the sensor chip 240. FIG. 5 is a schematic diagram of the imaging surface of the lens 210 under the photosensitive surface of the sensor chip 240. FIG. 6 is a schematic diagram of a partial cross-sectional structure of an under-screen biometric identification device 200. FIG. 7 is a schematic diagram of a partial cross-sectional structure of another off-screen biometric identification device 200. FIG. 8 is a schematic diagram of a partial cross-sectional structure of yet another off-screen biometric identification device 200.

As shown in FIG. 3, the under-screen biometric recognition device 200 may include: a lens 210, a lens barrel 220, an optical filter 230 and a sensor chip 240.

Wherein: the lens 210 is arranged below the display screen to receive the light signal returned from the human finger above the display screen, the light signal is used to detect the biometric information of the finger; the lens 210 Fixed in the lens barrel 220; the optical filter 230 is located below the lens 210; the sensor chip 240 is disposed below the lens barrel 220, the sensor chip 240 is used to pass through The optical signal of the lens 210 is imaged, and the distance between the photosensitive surface of the sensor chip 240 and the imaging surface of the lens 210 is greater than or equal to a preset value.

It should be noted that the display screen may be the display screens shown in FIG. 1 and FIG. 2, and for related descriptions, reference may be made to the above description about the display screen 120, and for the sake of brevity, no further description is provided here.

It should be understood that the photosensitive surface of the sensor chip 240 may be the upper surface thereof.

Optionally, in the embodiment of the present application, the sensor chip 240 may be an optical fingerprint sensor module composed of multiple optical fingerprint sensors.

Optionally, in the embodiment of the present application, the optical filter 230 completely covers the bottom of the lens 210.

Optionally, in the embodiment of the present application, the optical filter 230 may directly contact the lens 210, and there may also be a gap between the optical filter 230 and the lens 210, that is, the optical filter The sheet 230 does not directly contact the lens 210.

It should be noted that the optical filter 230 completely covers the bottom of the lens 210, so that all specific light waves in the optical signal passing through the lens 210 can be filtered out, for example, all Infrared light and / or blue light in the optical signal.

Optionally, in the embodiment of the present application, the optical filter is an infrared cut-off optical filter and / or a blue cut-off optical filter.

It should be understood that the optical filter 230 is used to reduce undesired background light in fingerprint sensing, so as to improve the optical sensing of the received light by the sensor chip 240. The optical filter 230 may be specifically used to filter out the wavelength of ambient light, for example, near infrared light and part of red light. For another example, blue light or part of blue light. For example, human fingers absorb most of the energy of light with wavelengths below ~ 580nm. If one or more optical filters or optical filter coatings can be designed to filter light with wavelengths from 580nm to infrared, the ambient light can be greatly reduced Impact on optical detection in fingerprint sensing.

Optionally, in an embodiment of the present application, the optical filter 230 may include one or more optical filters, and the one or more optical filters may be configured as, for example, a band-pass filter to allow OLED pixels The transmission of the emitted light also blocks infrared light and other light components in sunlight. When the under-screen biometrics recognition device 200 is used outdoors, such optical filtering can effectively reduce the background light caused by sunlight. The one or more optical filters may be implemented as, for example, an optical filter coating formed on one or more continuous interfaces, or may be implemented on one or more discrete interfaces. It should be understood that the optical filter 230 may be fabricated on the surface of any optical component, or along the optical path to the reflected light formed by the finger reflection to the sensor chip 240.

It should be noted that not only does the optical signal formed by the reflection of the human finger from above the display screen pass through the lens 210, but also the structured optical signal inside the display screen passes through the dispatch lens 210. At this time, the internal The structured light signal will affect the biometric information collection of the finger.

It should be understood that after the light emitted by the display screen is reflected by the finger above the display screen, a part of the reflected light may be received by the lens 210.

In the embodiment of the present application, the distance between the photosensitive surface of the sensor chip 240 and the imaging surface of the lens 210 is greater than or equal to a preset value, which can be understood that the photosensitive surface of the sensor chip 240 is out of focus status. The two optical signals passing through the lens 210 are high-frequency signals, but in comparison, when the photosensitive surface of the sensor chip 240 is out of focus, it is formed by reflection from the human finger above the display screen The optical signal passing through the lens 210 can still form a clear image on the photosensitive surface of the sensor chip 240, and the structured optical signal inside the display screen cannot pass through the lens 210 on the photosensitive surface of the sensor chip 240 Imaging (or, the structured light signal inside the display screen is blurred) can not affect the biometric information collection of the finger.

Optionally, in an embodiment of the present application, the imaging condition of the lens 210 may be the following optical imaging formula:

1 / u + 1 / v = 1 / f.

Where u is the object distance, v is the image distance, and f is the focal length. That is, the reciprocal of the object distance plus the reciprocal of the image distance is equal to the reciprocal of the focal length. In the embodiment of the present application, the distance between the upper surface of the display screen and the optical center of the lens 210 is the object distance, and the distance between the optical center of the lens 210 and the photosensitive surface of the sensor chip 240 is the image distance. The focal length of the lens 210 is a fixed value.

In other words, when the lens barrel 220 is fixed below the display screen, the distance between the upper surface of the display screen, the optical center of the lens 210 and the photosensitive surface of the sensor chip 240 needs to satisfy the above optical imaging formula.

Optionally, in order to eliminate the influence of the structured light signal inside the display screen on the imaging of the fingerprint signal, in the embodiment of the present application, the imaging surface of the lens 210 is located above or below the photosensitive surface of the sensor chip 240 . That is, in the imaging conditions of the lens 210 described above, when the object distance remains unchanged, the sensor chip can be realized by changing the relative position of the photosensitive surface of the sensor chip 240 and the imaging surface of the lens 210 240 The photosensitive surface is out of focus.

It should be noted that, in order to allow the sensor chip 240 to be clearly imaged, during design, the photosensitive surface of the sensor chip 240 may be designed to coincide with the imaging surface of the lens 210, and when the module is assembled, In order to overcome the influence of the structured light signal inside the display screen on the biometric information collection of the finger, it is necessary to control the assembly of the lens barrel 220 and / or the sensor chip 240 to make the sensor chip 240 photosensitive The plane is located above or below the imaging plane of the lens 210.

For example, as shown in FIG. 4, when the module is assembled, in order to position the imaging surface B of the lens 210 above the photosensitive surface A of the sensor chip 240, the lens 210 and the transmission The distance between the sensor chips 240 (the distance between the optical center O of the lens 210 and the photosensitive surface A of the sensor chip 240), for example, can increase the height of the lens barrel 220 (the height below the lens 210 in the lens barrel 220 ), And / or, add other filling materials (for example, fixing glue) between the lens barrel 220 and the sensor chip 240 to further realize that the imaging surface B of the lens 210 is located on the sensor chip 240 The purpose above the photosensitive surface A.

For another example, as shown in FIG. 5, when the module is assembled, in order to position the imaging surface B of the lens 210 below the photosensitive surface A of the sensor chip 240, the lens 210 and the The distance between the sensor chip 240 (the distance between the optical center O of the lens 210 and the photosensitive surface A of the sensor chip 240), for example, can reduce the height of the lens barrel 220 (below the lens 210 in the lens barrel 220 Height), or, reduce the height of the lens barrel 220 (the height below the lens 210 in the lens barrel 220) to add an optical filter between the lens barrel 220 and the sensor chip 240, and further realize The imaging surface B of the lens 210 is located below the photosensitive surface A of the sensor chip 240.

It should be understood that the optical center O of the lens 210 is a special point in the lens 210, and the propagation direction of light passing through the special point is unchanged. The optical center of the lens 210 is also called the optical center of the lens 210.

Optionally, in the above FIGS. 4 and 5, the optical filter 230 is fixed in the lens barrel 220, and the optical filter 230 is located below the lens 210. Further, the optical filter 230 is fixed on the side wall in the lens barrel 220 by direct contact.

Preferably, in the implementation of this application, the preset value is 10 μm. In other words, the distance between the photosensitive surface of the sensor chip 240 and the imaging surface of the lens 210 is greater than or equal to 10 μm. At this time, the influence of the structured light signal inside the display screen on the biometric information collection of the finger can be ignored.

Optionally, in some embodiments, the lens 210 may include a lens composed of at least one aspherical injection lens to reduce imaging distortion of the fingerprint image.

It should be noted that the focal length of the lens composed of at least one aspherical injection lens may be smaller than that of the front camera used for taking pictures or the lens 210 is a macro lens, so as to meet the requirements of off-screen fingerprint recognition. For example, the focal length of the macro lens may be 0.4mm-1.8mm. It should be noted that the range is only an exemplary range of gaps that satisfy imaging conditions, and embodiments of the present application are not limited thereto. For example, the focal length of the macro lens may be 2 mm.

Optionally, in the embodiment of the present application, the optical filter 230 may be fixed in the lens barrel 220 in the following two ways.

Manner 1: The optical filter 230 is fixed on the side wall of the lens barrel 220 by direct contact.

Manner 2: The under-screen biometric identification device further includes a filter holder 231, the optical filter 230 is fixed on the filter holder 231, and the filter holder 231 is fixed on the filter holder by direct contact On the side wall inside the lens barrel 220.

Specifically, as shown in FIG. 6, the optical filter 230 is fixed in the lens barrel 220 in the above manner.

Optionally, as shown in FIG. 6, the optical filter 230 forms a first dispensing structure 232 with the lens 210 near the lens barrel 220, and the optical filter 230 passes through the first The dispensing method in the dispensing structure 232 is fixed on the side wall in the lens barrel 220.

For example, organic glue is applied in the first dispensing structure 232 to fix the optical filter 230 on the side wall in the lens barrel 220.

It should be noted that, since the lens 210 may include a lens composed of at least one aspherical injection lens, the first dispensing structure 232 may be the lens 210 and the optical filter 230 in the lens barrel 220 The cavity structure naturally formed during internal assembly may also be a cavity structure actively formed by the lens 210 during assembly.

Optionally, as shown in FIG. 6, the optical filter 230 is fixed on the side wall in the lens barrel 220 by dispensing in the gap 233 in contact with the lens barrel 220.

In other words, the size of the optical filter 230 is smaller than that of the lens barrel 220. When the optical filter 230 is moved to the assembly position, the size between the optical filter 230 and the lens barrel 220 Dispensing in the gap 233 to fix the optical filter 230 on the side wall in the lens barrel 220.

For example, an organic glue is applied in the gap 233 to fix the optical filter 230 on the side wall in the lens barrel 220.

Optionally, as shown in FIG. 6, the optical filter 230 is fixed on the side wall in the lens barrel by dispensing 234 at the edge of its lower surface.

For example, 234 dots of organic glue are placed on the edge of the lower surface of the optical filter 230 to fix the optical filter 230 on the side wall in the lens barrel 220.

Optionally, the optical filter 230 may also be fixed on the side wall in the lens barrel by other means, for example, a step for supporting the optical filter 230 may be provided under the optical filter 230 structure.

Specifically, as shown in FIG. 7, the optical filter 230 is fixed in the lens barrel 220 in the above manner two.

Optionally, as shown in FIG. 7, the upper surface of the filter holder 231 extends toward the axis of the lens barrel 220 to form a first step structure 235, and the optical filter 230 is fixed in the first step structure 235 .

It should be noted that the first step structure 235 is made of a non-transparent material, that is, the optical signal passing through the lens 210 cannot pass through the first step structure 235.

Optionally, the optical filter 230 may be fixed in the first step structure 235 by applying organic glue on the first step structure 235.

Optionally, as shown in FIG. 7, the lower surface of the filter holder 231 extends toward the side wall of the lens barrel 220 to form an arc-shaped structure 236. The filter holder 231 passes through the arc-shaped structure 236 The internal dispensing method is fixed on the side wall in the lens barrel 220.

For example, an organic glue is added in the arc-shaped structure 236 to fix the filter holder 231 on the side wall of the lens barrel 220.

Optionally, as shown in FIG. 7, the filter holder 231 forms a second dispensing structure 237 with the lens 210 near the lens barrel 220, and the filter holder 231 passes through the second The dispensing method in the dispensing structure 237 is fixed on the side wall in the lens barrel 220.

For example, organic glue is added into the second dispensing structure 237 to fix the filter holder 231 on the side wall of the lens barrel 220.

It should be noted that since the lens 210 may include a lens composed of at least one aspherical injection lens, the second dispensing structure 237 may be the lens 210 and the filter holder 231 in the lens barrel 220 The cavity structure naturally formed during internal assembly may also be a cavity structure actively formed by the lens 210 during assembly.

Optionally, as shown in FIG. 7, the filter holder 231 is fixed on the side wall in the lens barrel 220 by dispensing glue in the gap 238 in contact with the lens barrel 220.

For example, an organic glue is applied in the gap 238 to fix the filter holder 231 on the side wall of the lens barrel 220.

Optionally, the filter holder 231 may also be fixed on the side wall in the lens barrel by other means, for example, a step for supporting the filter holder 231 may be provided under the filter holder 231 structure.

It should be noted that, in the embodiment of the present application, the optical filter 230 and the filter holder 231 may constitute an optical filter assembly. During assembly, the optical filter assembly is assembled in the lens barrel 220.

In order to achieve the above assembly purpose, the lens barrel 220 needs to be fixed.

Optionally, in some embodiments, the lens 210 and the lens barrel 220 constitute a semi-finished lens barrel assembly, and the optical filter 230 or the optical filter assembly and the semi-finished lens barrel assembly constitute a finished lens barrel.

Optionally, in the embodiment of the present application, the lens barrel 220 and its fixing components may be integratedly designed, that is, after the module is assembled, the lens barrel 220 (finished lens barrel) has a fixed assembly position, at this time , Which can not only meet the imaging conditions of the lens 210, but also overcome the influence of the structured light signal inside the display screen on the biological information collection of the finger.

Optionally, in an embodiment of the present application, the lens barrel 220 and its fixing components (for example, the lens barrel 220, the lens 210, and the optical filter 230 shown in FIG. 6 may be used, and for example, as shown in FIG. 7 The lens barrel 220, the lens 210, the optical filter 230 and the filter holder 231) are individually designed, that is, after the module is assembled, the lens barrel 220 has a fixed assembly position, and at this time, it can meet the requirements of the lens 210 The imaging conditions can overcome the influence of the structured light signal inside the display screen on the biometric information collection of the finger.

Specifically, as shown in FIG. 6 or FIG. 7, the lens barrel 220 has a second step structure 221 formed on the outer wall away from the barrel opening, and the second step structure 221 is used to fix the lens barrel 220.

It should be noted that the second step structure 221 can enhance the reliability of the connection between the lens barrel 220 and the sensor chip 240.

Optionally, the lens barrel 220 is fixed on the upper surface of the sensor chip 240 by fixing glue.

Optionally, the fixing glue has at least one of the following characteristics: impervious to visible light, having a thickness of 0.02 mm to 0.10 mm, a viscosity> 20000 mPas, and a curing shrinkage rate <3%.

For example, the fixing glue may be an glue belonging to an epoxy system or an acrylic system. The curing method of the fixing glue may be low-temperature curing within 85 ° C, Ultraviolet Rays (UV) curing, or UV curing combined with low-temperature curing within 85 ° C.

It should be noted that the principle of UV curing is that the photoinitiator (or photosensitizer) in the UV curing material generates active radicals or cations after absorbing ultraviolet light under ultraviolet irradiation, which initiates polymerization of monomers and crosslinking chemical reactions, making the adhesive The mixture changes from liquid to solid in seconds.

It should be understood that the second stepped structure 221 may be continuous surrounding and fixing the lens barrel 220, or may be discretely surrounding and fixing the lens barrel 220, which is not specifically limited in this embodiment of the present application.

Specifically, as shown in FIG. 6 or FIG. 7, the lens barrel 220 may be supported by a lens holder 250, and a third dispensing structure 251 is formed between the lens holder 250 and the lens barrel 220. The lens holder The 250 and the lens barrel 220 are fixed by dispensing in the third dispensing structure 251. For example, as shown in FIG. 6 or FIG. 7, the third dispensing structure may include a glue accommodating space formed by the upper surface of the lens holder 250 extending downward near the peripheral area of the lens barrel 220, thereby The lens barrel 220 and the lens holder 250 may be fixedly connected by dispensing in the accommodating space.

It should be understood that the third dispensing structure 251 may include one or more accommodating spaces, which is not specifically limited in the embodiments of the present application.

It should also be understood that the third dispensing structure 251 may be continuous or discrete around the lens barrel 220. The embodiments of the present application are not specifically limited.

Specifically, in order to fix the lens holder 250, the lower surface of the lens holder 250 extends downward at an edge away from the lens barrel 220 to form a first fixing structure 252.

It should be noted that the first fixing structure 252 may be continuous or discrete in a certain direction, which is not limited in this embodiment of the present application.

In order to ensure that the lens 210 can be stably fixed in the lens barrel 220. Optionally, in an embodiment of the present application, a structure for preventing the lens 210 from moving upward may be provided at the mouth of the upper surface of the lens barrel 220. For example, as shown in FIG. 6 or FIG. 7, the upper surface of the lens barrel 220 extends inward at the barrel opening to form a first convex structure 222, and the first convex structure 222 is used to fix the lens. Optionally, in another embodiment of the present application, in order to prevent the lens 210 from moving downward, the inner surface of the lens barrel 220 and the lens 210 may be fixed by means of adhesive material fixing.

Optionally, in an embodiment of the present application, the upper surface of the first convex structure 222 may be designed as a specific structure, such as a funnel structure or a bevel structure, so that the optical signal reflected from the display screen via a human finger Pass through the first convex structure 222 as much as possible, thereby increasing the amount of signal received by the lens 210. For example, as shown in FIG. 6 or FIG. 7, the upper surface of the lens barrel 220 is chamfered at the mouth to form a bevel, so that the inner diameter of the lens barrel 220 at the upper surface is larger than that of the lens barrel 220. The inner diameter of the first convex structure 222.

Optionally, in an embodiment of the present application, an additional space for containing glue may be provided between the inner surface of the lens barrel 220 and the lens 210 to increase the inner surface of the lens barrel 220 and the The reliability of the bonding between the lenses 210. For example, a third step structure 223 is formed on the inner surface of the lens barrel 220 below the first convex structure 222, and the lens 210 passes through the first convex structure 222 and the third step structure 223 It is fixed in the lens barrel 220. Specifically, the third step structure 223 can greatly increase the accommodation space of the glue.

It should be noted that the third step structure 223 may be replaced by the optical filter 230 shown in FIG. 6 or FIG. 7. For example, in the structure shown in FIG. 6, the lens 210 may be fixed on the side wall in the lens barrel 220 by dispensing in the first dispensing structure 232. For another example, in the structure shown in FIG. 7, the lens 210 may be fixed on the side wall in the lens barrel 220 by dispensing in the second dispensing structure 237.

Optionally, in the embodiment of the present application, foam may be provided on the upper surface of the lens holder 250 to achieve the purpose of sealing and dustproof.

Optionally, as shown in FIG. 6 or FIG. 7, the lens holder 250 has a cavity structure formed between the second step structure 221 and the first fixing structure 252. It should be understood that some passive components such as capacitors and microcontroller units (MCUs) may be disposed in the cavity structure formed between the second step structure 221 and the first fixing structure 252.

Optionally, in the embodiment of the present application, as shown in FIG. 8, the lens holder 250 and the lens barrel 220 are an integral structure, which may be referred to as a lens barrel assembly. For details, see the lens barrel assembly 220 in FIG. 8 .

It should be noted that FIG. 8 is a schematic diagram of the overall structure of the lens holder 250 and the lens barrel 220 in the under-screen biometrics identification device 200 shown in FIG. 6. It can be a whole structure, and for the sake of brevity, it will not be repeated here.

It should be understood that, in a specific implementation, the lens 210, the lens barrel 220, and the lens holder 250 may also be designed with other structures. For example, the lens 210 may also be designed with a size mark (a) of the lens 210, the lens barrel 220 may also be designed with a size mark (A1) of the lens barrel 220, and the lens barrel 220 may also be designed with an assembly size, In the assembly process of the module, the lens barrel 220 may be assembled based on the assembly size. For example, different manufacturers may use different apertures and hole depths (that is, the diameter and depth of the lens barrel 220). For example, the lens barrel 220 may also be designed with a hole for fixing the lens barrel 220, such as a screw fixing hole. For another example, the lens holder 250 may also be designed with a hole for fixing the lens holder 250, such as a screw fixing hole.

9 is a schematic diagram of an off-screen biometrics identification device 200 according to an embodiment of the present application. Specifically, as shown in FIG. 9, a schematic diagram of a partial cross-sectional structure of a flexible printed circuit board 260 is also integrated in the under-screen biometric identification device 200.

Specifically, the under-screen biometric identification device 200 may further include a circuit board for transmitting signals, as shown in FIG. 9, the circuit board may be a flexible printed circuit board (Flexible Printed Circuit, FPC) 260.

Alternatively, the sensor chip 240 may be fixed on the upper surface of the flexible printed circuit board 260 by die bonding glue, and the sensor chip 240 is electrically connected to the flexible printed circuit board 260 through a binding wire 261 . The sensor chip 240 may also be soldered to the flexible printed circuit board 260 through pads. Specifically, the sensor chip 240 can realize electrical interconnection and signal transmission with other peripheral circuits or other elements of the electronic device 100 as shown in FIG. 1 or FIG. 2 through the flexible printed circuit board 260. For example, the sensor chip 240 may receive the control signal of the processing unit of the electronic device 100 through the flexible printed circuit board 260, and may also detect the biometric detection signal through the flexible printed circuit board 260 (Eg, fingerprint image) output to the processing unit or control unit of the electronic device 100.

Optionally, as shown in FIG. 9, the lower surface of the first fixing structure 252 and the upper surface of the flexible printed circuit board 260 are fixedly connected in the edge area of the sensor chip 240.

Specifically, the lower surface of the first fixing structure 252 of the lens holder 250 may be sealed and adhered by means of fixing glue on the flexible printed circuit board 260. For example, the fixing adhesive may be an adhesive belonging to an epoxy system or an acrylic system. The fixing adhesive has at least one of the following characteristics: impervious to visible light, a thickness of 0.02 mm to 0.10 mm, a viscosity> 20000 mPas, and a curing shrinkage rate <3%. The curing method of the fixing glue may be low-temperature curing within 85 ° C, Ultraviolet Rays (UV) curing, or UV curing combined with low-temperature curing within 85 ° C.

As shown in FIG. 9, since the lens holder 250 is fixed on the upper surface of the flexible printed circuit board 260, a closed space is formed between the lens holder 250 and the flexible printed circuit board 260. In order to avoid that the pressure of this closed space is too large or too small, the stability of the under-screen biometric identification device 200 is affected.

Optionally, in an embodiment of the present application, a vent hole may be formed on the mirror base 250 as shown in FIG. 9, the vent hole is used to adjust the mirror base 250 and the flexible printed circuit The air pressure intensity of the internal space formed by the plate 260.

Optionally, in an embodiment of the present application, the under-screen biometric identification device 200 further includes a steel plate, and the steel plate is fixed on the lower surface of the flexible printed circuit board 260.

Optionally, in an embodiment of the present application, the under-screen biometric identification device further includes: a fixing frame 270.

Specifically, as shown in FIG. 10, the lens holder 250 is fixed below the display screen by the fixing bracket 270, and the distance between the upper surface of the display screen and the optical center of the lens 210 is satisfied Imaging conditions.

Optionally, the fixing frame 270 and the lens holder 250 can be installed and fixed by at least one of the following installation methods: screw installation fixing method, glue material fixing method, welding fixing method, and coupling fixing the way.

In the embodiment of the present application, the under-screen biometrics identification device 200 can be installed below the display screen by being fixedly connected to a device easily removable inside the terminal device.

In other words, the above-mentioned easily removable device can be used as a fixing frame 270 between the under-screen biometric identification device 200 and the display screen. The under-screen biometrics identification device 200 may be fixedly arranged below the display screen in a non-contact manner through other auxiliary elements. For example, the under-screen biometrics recognition device 200 may be fixed to the fixing frame 270, and fixedly disposed under the display screen through the fixing frame 270.

It should be noted that the above FIGS. 9 and 10 are described by taking the optical filter 230 fixed in the lens barrel 220 in the above manner as an example, that is, the optical filter 230 is fixed in the lens barrel by direct contact The side walls in 220 correspond to Figs. 3 and 6. Of course, the flexible printed circuit board 260 and the fixing frame 270 may also be integrated in the under-screen biometrics identification device 200 as shown in FIG. 7, for the sake of brevity, no further description is provided here.

Optionally, in an embodiment of the present application, when the off-screen biometric identification device 200 is applied to a terminal device (such as a smart phone), the fixing bracket 270 is a middle frame of the terminal device, the middle The frame is used to support the display screen. The under-screen biometrics identification device 200 and the display screen may be fixed below the display screen through a middle frame or other components of the terminal device.

FIG. 11 is a schematic diagram of fixing the under-screen biometric identification device 200 under the display screen 320 through the middle frame 370. The off-screen biometric identification device 200 may be as shown in FIG. 6, may also be as shown in FIG. 7, or may be as shown in FIG. 8. The following description will be made by taking the off-screen biometric identification device 200 as the off-screen biometric identification device 200 shown in FIG. 6 as an example.

Specifically, the display screen 320 may be the OLED display screen 120 shown in FIGS. 1 and 2, and the under-screen biometric identification device 200 may be the optical fingerprint identification device 130 shown in FIGS. 1 and 2. It may include a lens 210, a lens barrel 220, an optical filter 230, a sensor chip 240, a lens holder 250, a flexible printed circuit board 260, and so on. The under-screen biometrics identification device 200 can be used to collect fingerprints or other biometrics, and its biometrics collection area is at least partially within the display area of the display screen 320 shown. For the specific structure, function, and biometric detection and identification process of the display screen 320 and the under-screen biometric identification device 200, reference may be made to the foregoing description about the OLED display 120 and the optical fingerprint identification device 130, and details are not described here.

Optionally, the sensor chip 240 may be an optical fingerprint sensor module composed of multiple optical fingerprint sensors.

The middle frame 370 is a frame of the electronic device that is disposed between the display screen 320 and the back cover and used to carry various internal components. The various internal components include but are not limited to batteries, motherboards, cameras, cables, various sensors, and microphones , Earpieces and other parts.

The middle frame 370 can be made of metal or alloy material, or even made of plastic material. In this case, the middle frame 370 can even be integrally formed with the frame of the mobile terminal, and the integrated molding refers to the internal middle frame and the frame Is a whole. For example, the frame can be just a metal welt, or a metal-like coating can be applied to the middle frame. Further, the middle frame 370 may also be a composite middle frame, for example, including an inner middle frame and an outer middle frame, wherein the inner middle frame is used to carry mobile phone parts (such as a lens holder 250), and the outer middle frame is the inner middle Outside the frame, there are mobile phone buttons on the outer edge of the outer middle frame, and the inner middle frame is integrated with the outer middle frame.

Optionally, in an embodiment of the present application, there is a gap between the under-screen biometric identification device 200 and the display screen 320.

It should be understood that the gap between the under-screen biometric recognition device 200 and the display screen 320 is intended to make the distance between the upper surface of the display screen and the optical center of the lens 210 satisfy imaging conditions. The size and specific meaning of the gap are not limited.

For example, the gap may be determined by a manufacturer through debugging during the installation of the biometric device 200, or may be specified by each manufacturer.

For another example, the gap may be the distance between the upper surface of the lens barrel 220 and the lower surface of the display screen 320, or may be the distance between the upper surface of the lens holder 250 and the lower surface of the display screen 320.

Optionally, in an embodiment of the present application, the gap width between the under-screen biometric identification device 200 and the display screen 320 may be greater than or equal to a first distance, and the first distance is the The minimum distance between the lens barrel 220 and the display screen 320 when the terminal device is in a shock state such as falling or collision.

For example, the gap width may range from 0.3mm to 1mm. It should be noted that the range is only an example range of the gap, and the embodiments of the present application are not limited thereto.

It should be understood that although the middle frame 370 is taken as an example of the fixing frame in the above embodiment, in other embodiments, the under-screen biometric identification device 200 may be fixedly connected inside the terminal device to be easily removable Any device can be installed under the display screen 320 and ensure that there is a gap between the under-screen biometric identification device 200 and the display screen 320. As long as the under-screen biometrics recognition device 200 can be fixedly arranged below the display screen 320 in a non-contact manner. In other embodiments, the under-screen biometric identification device 200 may also be fixed to easily removable devices such as the back cover of the mobile terminal, the motherboard, and the battery, and further fixedly disposed under the display screen 320.

Since the under-screen biometrics identification device 200 is disposed below the display screen 320 in a non-contact manner and does not contact the lower surface of the display screen 320, that is, the under-screen biometrics identification device 200 and all The display screen 320 is completely decoupled, which avoids damage to the display screen 320 when the off-screen biometric identification device 200 is disassembled.

In addition, since the under-screen biometric identification device 200 and the lower surface of the display screen 320 are not in contact, a fixed gap is maintained between the two, and the gap may be an air gap not filled with any auxiliary materials (air gap) ), Which can ensure that when the display screen 320 is pressed or the terminal device falls or crashes, the under-screen biometric identification device 200 does not touch the lower surface of the display screen 320, nor does it affect the The biometric recognition stability and performance of the off-screen biometric recognition device 200.

In summary, the embodiment of the present application can reduce the difficulty of disassembling the under-screen biometric identification device 200 by separating the under-screen biometric identification device 200 from the lower surface of the display screen 320, thereby improving Maintainability of terminal equipment. Further, it is possible to reduce the complexity of installing the under-screen biometric identification device 200 under the display screen 320 during the production process of the under-screen biometric identification device, and improve the under-screen biometric identification device Production success rate, which in turn reduces production costs. In addition, the stability and performance of the biometric recognition device 200 of the off-screen biometric recognition device will not be affected.

It should be noted that, in the embodiment of the present application, the positional relationship between the display screen 320 and the middle frame 370 is relatively fixed.

Optionally, in an embodiment of the present application, as shown in FIG. 11, a screen assembly flexible circuit board 360 is further included between the display screen 320 and the middle frame 370, and the display screen 320 may pass the The screen assembly flexible circuit board 360 realizes electrical interconnection and signal transmission with other peripheral circuits or other elements of the electronic device 100 as shown in FIG. 1 or FIG. 2.

Optionally, as shown in FIG. 11, a foam 340 is provided between the display screen 320 and the flexible circuit board 360 of the screen assembly, and the foam 340 is bonded to the display screen 320 by an optical adhesive 330. The foam 340 adheres the flexible circuit board 360 of the screen assembly through the optical glue 350. In other words, the screen assembly flexible circuit board 360 is fixed below the display screen 320 by the optical glue 330, the foam 340 and the optical glue 350.

It should be noted that in addition to the foam 340 used in conjunction with the optical glue 330 and the optical glue 350 to bond the flexible circuit board 360 of the screen assembly and the display screen 320, it also has a sealed dustproof effect.

Optionally, as shown in FIG. 11, the middle frame 370 and the screen assembly flexible circuit board 360 are hermetically connected by foam 380, which is a compressible foam with adhesive on at least one side. Optionally, the compression rate of the foam 380 is> 50%. When the foam 380 is glued on both sides, the adhesiveness of the adhesive bonded to the flexible circuit board 360 of the screen assembly is weaker than the adhesiveness of the adhesive bonded to the middle frame 370.

It should be noted that the foam 380 not only is used for bonding the flexible circuit board 360 of the screen assembly and the middle frame 370, but also has the effect of sealing and dustproof. When the fixed connection is performed by the double-sided adhesive fixing method or the optical adhesive fixing method, the stability of the fixed connection can be increased.

Optionally, as shown in FIG. 11, a positioning post 253 is provided on the lens holder 250 of the under-screen biometric identification device 200, a positioning hole 371 is provided on the middle frame 370, and the positioning post 253 and the The positioning hole 371 can form precise positioning, and at the same time, the positioning post 253 and the positioning hole 371 are bonded by a double-sided adhesive 390, which is a double-sided adhesive with a certain thickness and size retention .

Optionally, as shown in FIG. 11, each stack between the display screen 320 and the under-screen biometric identification device 200 has an opening formed in the installation area of the under-screen biometric identification device 200, so The under-screen biometrics identification device 200 is disposed below the opening, and its optical sensing array is directly opposed to the lower surface of the display screen 320 through the opening. Therefore, when the under-screen biometric identification device 200 is disposed on the lower surface of the middle frame 370, it can be ensured that the under-screen biometric identification device 200 can receive the above-mentioned reflected light through the opening.

It should be understood that the embodiments of the present application do not specifically limit the size of the opening. For example, the size of the opening of the middle frame 370 may be smaller than or equal to the size of the under-screen biometric identification device 200. For another example, the size of the opening of the middle frame 370 may also be greater than or equal to the size of the lens barrel 220.

Optionally, in an embodiment of the present application, the size of the opening of the middle frame 370 is larger than the size of the lens barrel 220, and the size of the opening 371 of the middle frame 370 is smaller than the under-screen biometrics The size of the identification device 200. In this case, the lens barrel 220 may be partially accommodated in the opening of the middle frame 370, and a buffer space may be formed between the lens barrel 220 and the middle frame 370, which can ensure that when the middle frame 370 is pressed or the terminal When the device is dropped or collided, the lens barrel 220 will not touch the middle frame 370, nor will it affect the stability and performance of the biometric recognition of the under-screen biometric recognition device 200.

It should be noted that the distance from the display screen 320 to the middle frame 370 constitutes a partial image distance of the under-screen biometric identification device 200. Within the distance range of this constituent image distance, the display screen 320 The openings of the materials of each laminated structure underneath must not block the effective optical path, and at the same time, a good seal is formed between the laminated layers to avoid pollution to the lens (mainly referring to the light signal pollution), thereby affecting the imaging quality.

Optionally, in an embodiment of the present application, as shown in FIG. 11, when the under-screen biometric identification device 200 is applied to a terminal device, a cover 310 is further provided on the upper surface of the display screen 320 . The cover plate 310 may be a transparent protective cover plate, such as a glass cover plate or a sapphire cover plate, which may cover the display screen 320, and the lower surface of the cover plate 310 may be The upper surface (that is, the display surface) is bonded. The display screen 320 and the cover plate 310 may be connected by an adhesive layer or other connection methods, which is not limited in the embodiment of the present application.

In the embodiment of the present application, when the off-screen biometric identification device 200 uses optical means to perform biometric identification, such as optical fingerprint identification, the under-screen biometric identification device 200 needs to detect that the optical signal from the display screen 320 passes through the finger Reflection light formed by reflection.

In actual products, if the thickness of the middle frame 370 is thick, optionally, in an embodiment of the present application, the installation area of the under-screen biometric identification device 200 on the middle frame 370 may also be Perform thinning treatment.

Through the above analysis, it can be found that in the embodiment of the present application, the under-screen biometric identification device 200 and the display screen 320 are designed separately, for example, the under-screen biometric identification device 200 can be fixed on the middle frame 370 or the back cover structural member, It solves the problems that the current under-screen biometric identification device directly affixes the under-screen biometric identification device 200 to the display screen 320, which is difficult to disassemble, easy to damage the display screen 320, and has high difficulty in process bonding.

In addition, in the embodiment of the present application, a gap is formed between the under-screen biometric identification device 200 and the lower surface of the display screen 320, the gap can ensure that the display screen 320 is pressed or when the terminal When the device is dropped or collided, the under-screen biometric identification device 200 does not touch the lower surface of the display screen 320 to avoid damaging the display screen 320.

In the embodiment of the present application, the above-mentioned off-screen biometric identification device 200 may also be referred to as a biometric identification module. The photodetector array can also be referred to as a photoelectric sensor array, which can transmit light from the lens 210. For example, the photosensor array may use an array of photodiodes, and the photodiodes convert the optical signals into electrical signals, so that imaging can be performed according to the electrical signals.

12 is a schematic diagram of the assembly process of the off-screen biometric identification device 200. Specifically, the assembly process 400 includes:

401, passive component placement.

Passive components such as capacitors and MCUs are fixed on the sensor chip 240, and the passive components are electrically connected to the sensor chip 240.

402, the sensor chip is attached.

The sensor chip 240 is fixed on the flexible printed circuit board 260 through die bonding glue.

403, sensor chip bonding.

The sensor chip 240 is electrically connected to the flexible printed circuit board 260 through the bonding wire 261.

404, the lens assembly is attached.

In the scheme of the off-screen biometric identification device 200 described in FIGS. 3, 6, 7, and 8, the lens 210 is installed in the lens barrel 220.

405, the optical filter is attached.

Specifically, in the solution of the under-screen biometrics identification device 200 shown in FIG. 6, the optical filter 230 may be fixed in the lens barrel 220 by dispensing in the first dispensing structure 232 On the side wall of the lens barrel; the optical filter 230 can also be fixed on the side wall of the lens barrel 220 by dispensing in the gap 233 in contact with the lens barrel 220; the optical filter 230 also It can be fixed on the side wall in the lens barrel by 234 dispensing at the edge of its lower surface.

Optionally, in step 405, the optical filter assembly may also be attached.

Optionally, in the solution of the under-screen biometrics recognition device 200 shown in FIG. 7, the optical filter 230 is fixed on the filter holder 231, and the filter holder 231 is fixed by direct contact On the side wall inside the lens barrel 220.

Specifically, a first step structure 235 is formed on the upper surface of the filter holder 231 extending in the axis direction of the lens barrel 220, and the optical filter 230 is fixed in the first step structure 235.

For example, the optical filter 230 may be fixed in the first step structure 235 by applying organic glue on the first step structure 235.

The filter holder 231 may be fixed on the side wall of the lens barrel 220 by dispensing in the arc-shaped structure 236; the filter holder 231 may also be installed in the second dispensing structure 237 is fixed on the side wall of the lens barrel 220 by dispensing; the filter holder 231 can also be fixed to the lens barrel by dispensing in the gap 238 in contact with the lens barrel 220 220 on the side wall.

406, the lens holder fits.

Specifically, in the solution of the off-screen biometrics identification device 200 shown in FIG. 6 or FIG. 7, the lens barrel 220 may be fixed by dispensing in the third dispensing structure 251.

Optionally, a second step structure 221 is formed on the outer wall of the lens barrel 220 away from the barrel opening, and the second step structure 221 is used to fix the lens barrel 220. For example, the lens barrel 220 is fixed on the sensor chip 240 by fixing glue under the second step structure 221.

Optionally, the lower surface of the lens holder 250 extends downward at an edge away from the lens barrel 220 to form a first fixing structure 252. For example, the lens holder 250 is fixed on the flexible printed circuit board 260 by fixing glue under the first fixing structure 252.

Specifically, the fixing adhesive may be an adhesive belonging to an epoxy system or an acrylic system. The fixing adhesive has at least one of the following characteristics: impervious to visible light, a thickness of 0.02 mm to 0.10 mm, a viscosity of> 20000 mPas, and curing shrinkage The rate is less than 3%. The curing method of the fixing glue may be low temperature curing within 85 ° C, UV curing, or UV curing combined with low temperature curing within 85 ° C.

407, functional test.

At this time, the test of the off-screen biometric identification device 200 is mainly performed, for example, a fingerprint detection test.

408, Double-sided tape is attached to the surface of the module.

The above-mentioned module is the under-screen biometric identification device 200. When the test is passed in step 407, double-sided tape is attached to the upper surface of the lens holder 250 of the under-screen biometric identification device 200.

409, the module is attached to the middle frame component.

The mirror base 250 and the middle frame 370 (fixing member 270) of the under-screen biometric identification device 200 are fixed by double-sided tape.

410, functional test.

At this time, a comprehensive test is performed, that is, a complete machine test. When the test is suitable, the assembly process is completed.

An embodiment of the present application further provides a biometrics identification component, which may include an off-screen biometrics identification device and a module bracket; when the biometrics identification component is applied to the off-screen biometrics identification device as described above or When the terminal device is installed, it can be directly installed to the middle frame or the fixing frame of the terminal device, and when the under-screen biometric identification device or the under-screen biometric identification device of the terminal device is damaged, the damaged The replacement of the biometric identification component can further reduce the complexity of maintenance and device replacement of the biometric identification device under the replacement screen, and avoid damage to the display screen.

An embodiment of the present application also provides an electronic device. The electronic device may include a display screen and the above-mentioned off-screen biometric identification device in various embodiments of the present application. The under-screen biometric identification device is provided on the display screen. Below, and the distance between the upper surface of the display screen and the optical center of the lens in the biometric identification device under the screen meets the imaging conditions.

The electronic device may be any electronic device with a display screen, which uses the technical solution of the embodiments of the present application to implement off-screen biometric identification. The display screen may be an organic light emitting diode display screen, including a plurality of organic light emitting diode light sources, wherein the under-screen biometric identification device uses at least part of the organic light emitting diode light source as an excitation light source for biometric identification.

It should be understood that the specific examples in the embodiments of the present application are only to help those skilled in the art to better understand the embodiments of the present application, rather than limiting the scope of the embodiments of the present application.

It should be understood that the terms used in the embodiments of the present application and the appended claims are only for the purpose of describing specific embodiments, and are not intended to limit the embodiments of the present application. For example, the singular forms "a", "above", and "said" used in the embodiments of the present application and the appended claims are also intended to include most forms unless the context clearly indicates other meanings.

Those of ordinary skill in the art may realize that the units of the examples described in conjunction with the embodiments disclosed herein can be implemented by electronic hardware, computer software, or a combination of the two, in order to clearly illustrate the interchangeability of hardware and software In the above description, the composition and steps of each example have been generally described according to function. Whether these functions are executed in hardware or software depends on the specific application of the technical solution and design constraints. Professional technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

In the several embodiments provided in this application, it should be understood that the disclosed system and device may be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a division of logical functions. In actual implementation, there may be other divisions, for example, multiple units or components may be combined or Can be integrated into another system, or some features can be ignored, or not implemented. In addition, the displayed or discussed mutual couplings or direct couplings or communication connections may be indirect couplings or communication connections through some interfaces, devices, or units, and may also be electrical, mechanical, or other forms of connection.

The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or may be distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the objectives of the solutions of the embodiments of the present application.

In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The above integrated unit can be implemented in the form of hardware or software function unit.

If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it may be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application is essentially or part of the contribution to the existing technology, or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a The storage medium includes several instructions to enable a computer device (which may be a personal computer, server, or network device, etc.) to perform all or part of the steps of the methods described in the embodiments of the present application. The aforementioned storage media include: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), magnetic disk or optical disk and other media that can store program code .

The above is only the specific implementation of this application, but the scope of protection of this application is not limited to this, any person skilled in the art can easily think of various equivalents within the technical scope disclosed in this application Modifications or replacements, these modifications or replacements should be covered within the scope of protection of this application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

An under-screen biometrics identification device, characterized in that it includes:

The lens is arranged below the display screen to receive the light signal returned from the human finger above the display screen, the light signal is used to detect the biometric information of the finger;

Lens barrel, the lens is fixed in the lens barrel;

An optical filter, the optical filter is located below the lens;

A sensor chip, the sensor chip is disposed below the lens barrel, the sensor chip is used for imaging based on the optical signal passing through the lens, wherein the photosensitive surface of the sensor chip and the The distance between the imaging surfaces of the lens is greater than or equal to a preset value.
The under-screen biometric identification device according to claim 1, wherein the optical filter is fixed on the side wall in the lens barrel by direct contact.
The under-screen biometric identification device according to claim 2, wherein the optical filter forms a first dispensing structure with the lens near the lens barrel, and the optical filter passes through the The dispensing method in the first dispensing structure is fixed on the side wall in the lens barrel.
The under-screen biometrics identification device according to claim 2 or 3, wherein the optical filter is fixed to the side wall of the lens barrel by dispensing in a gap contacting the lens barrel On the top, or alternatively, the optical filter is fixed on the side wall in the lens barrel by dispensing glue on the edge of its lower surface.
The under-screen biometric identification device according to claim 1, wherein the under-screen biometric identification device further comprises a filter holder, the optical filter is fixed on the filter holder, and the filtering The film holder is fixed on the side wall in the lens barrel by direct contact.
The under-screen biometric identification device according to claim 5, wherein a first step structure is formed on the upper surface of the filter holder extending in the direction of the lens barrel axis, and the optical filter is fixed at the first Within the step structure.
The under-screen biometric identification device according to claim 5 or 6, wherein:

The lower surface of the filter holder extends toward the side wall of the lens barrel to form an arc-shaped structure, and the filter holder is fixed to the side wall in the lens barrel by dispensing glue in the arc-shaped structure on.
The under-screen biometric identification device according to any one of claims 5 to 7, wherein the filter holder is formed with a second dispensing structure near the lens barrel and the lens, the The filter holder is fixed on the side wall in the lens barrel by dispensing in the second dispensing structure.
The under-screen biometrics identification device according to any one of claims 5 to 8, wherein the filter holder is fixed to the lens barrel by dispensing in a gap in contact with the lens barrel On the inner side wall.
The under-screen biometrics identification device according to any one of claims 1 to 8, wherein the optical filter completely covers the bottom of the lens.
The under-screen biometric identification device according to any one of claims 1 to 10, wherein the optical filter is an infrared cut-off optical filter and / or a blue cut-off optical filter.
The under-screen biometric identification device according to any one of claims 1 to 11, wherein the imaging surface of the lens is located above or below the photosensitive surface of the sensor chip.
The under-screen biometric identification device according to any one of claims 1 to 12, wherein the preset value is 10 μm.
The under-screen biometric identification device according to any one of claims 1 to 13, wherein the lens includes a lens composed of at least one aspherical injection lens.
The under-screen biometric identification device according to any one of claims 1 to 14, wherein the lens is a macro lens.
The under-screen biometric identification device according to claim 15, wherein the focal length of the macro lens is 0.4mm-1.8mm.
The under-screen biometric identification device according to any one of claims 1 to 16, wherein the under-screen biometric identification device further comprises:

A lens holder, the lens holder is used to support the lens barrel.
The under-screen biometric identification device according to claim 17, characterized in that a third dispensing structure is formed on the upper surface of the lens holder extending downward in the peripheral area near the lens barrel, and the lens holder is The lens barrels are fixed by dispensing in the third dispensing structure.
The under-screen biometrics identification device according to claim 17, wherein the lens holder and the lens barrel have an integral structure.
The under-screen biometric identification device according to any one of claims 17 to 19, wherein the lens barrel is formed with a second step structure on an outer wall away from the barrel opening, the second step structure is used for fixing The lens barrel.
The under-screen biometric identification device according to any one of claims 17 to 20, wherein the lower surface of the lens holder extends downward at an edge away from the lens barrel to form a first fixing structure, so The first fixing structure is used to fix the lens holder.
The under-screen biometric identification device according to any one of claims 17 to 21, wherein the upper surface of the lens barrel extends inward at the barrel opening to form a first convex structure, the first convex The structure is used to fix the lens.
The under-screen biometric identification device according to claim 22, wherein the upper surface of the lens barrel is chamfered at the mouth of the barrel to form a bevel so that the inner diameter of the lens barrel at the upper surface is greater than The inner diameter of the lens barrel at the first convex structure.
The under-screen biometrics identification device according to claim 22 or 23, wherein a third step structure is formed under the first convex structure on the inner surface of the lens barrel, and the lens passes through the The first convex structure and the third step structure are fixed in the lens barrel.
The under-screen biometric identification device according to any one of claims 17 to 24, wherein the lens barrel is fixed on the upper surface of the sensor chip.
The under-screen biometric identification device according to claim 25, wherein the lens barrel is fixed on the upper surface of the sensor chip by a fixing glue.
The under-screen biometric identification device according to claim 26, wherein the fixing glue has at least one of the following characteristics: visible light impermeability, thickness 0.02mm ～ 0.10mm, viscosity> 20000mPas, curing shrinkage <3%.
The under-screen biometric identification device according to any one of claims 17 to 27, wherein the under-screen biometric identification device further comprises:

A flexible printed circuit board, the sensor chip is fixed on the upper surface of the flexible printed circuit board, and the lower surface of the lens holder and the upper surface of the flexible printed circuit board are on the edge of the sensor chip The area is fixedly connected.
The under-screen biometrics identification device according to claim 28, characterized in that the lens holder realizes sealing and bonding by means of spot-fixing glue on the flexible printed circuit board.
The under-screen biometrics identification device according to claim 29, wherein the lens holder is formed with an exhaust hole, and the exhaust hole is used to adjust the lens holder and the flexible printed circuit board. Air pressure intensity in the internal space.
The under-screen biometrics identification device according to any one of claims 28 to 30, wherein the sensor chip is fixed on the upper surface of the flexible printed circuit board by solid crystal glue, and the transmission The sensor chip is electrically connected to the flexible printed circuit board through a binding wire.
The under-screen biometric identification device according to any one of claims 17 to 31, wherein the under-screen biometric identification device further comprises:

A fixing frame, the lens base is fixed below the display screen through the fixing frame, and the distance between the upper surface of the display screen and the optical center of the lens satisfies imaging conditions.
The under-screen biometrics identification device according to claim 32, wherein the fixing frame and the lens holder are installed and fixed by at least one of the following installation methods: screw installation and fixing method, adhesive material bonding Fixing method, welding fixing method and coupling fixing method.
The under-screen biometric identification device according to claim 32 or 33, wherein the under-screen biometric identification device is applied to an electronic device, and the fixing frame is a middle frame of the electronic device, the middle frame Used to support the display screen.
The under-screen biometric identification device according to claim 34, wherein the middle frame is formed with an opening, the lens barrel is at least partially accommodated in the opening, the outside of the lens barrel and the opening There is a gap between the inside of the hole.
The under-screen biometric identification device according to claim 35, wherein the upper surface of the middle frame is formed with a chamfer at the edge of the opening by chamfering, and the bevel angle makes the middle frame The opening width of the surface is larger than the opening width of the lower surface of the middle frame.
An electronic device, characterized in that it includes:

The off-screen biometric identification device according to any one of claims 1 to 36.
The electronic device according to claim 37, wherein the electronic device further comprises:

A display screen, the under-screen biometric identification device is disposed below the display screen, and the distance between the upper surface of the display screen and the optical center of the lens in the under-screen biometric identification device satisfies a predetermined Imaging conditions, wherein the biometric collection area of the under-screen biometric identification device is at least partially located in the display area of the display screen.
The electronic device according to claim 38, wherein the electronic device further comprises: a middle frame, and the under-screen biometric identification device is assembled under the display screen through the middle frame, so that the There is a gap between the under-screen biometric identification device and the display screen.
The electronic device according to claim 39, characterized in that the electronic device further comprises a screen assembly flexible circuit board, the screen assembly flexible circuit board is located between the display screen and the middle frame, and the screen The flexible circuit board of the component is sealed and fixed by the compressible foam with adhesive on at least one side.
The electronic device according to claim 40, wherein if the foam is glued on both sides, the adhesive of the foam and the flexible circuit board of the screen assembly is weaker than the foam and the foam The middle frame is adhesive to the adhesive glue.
The electronic device according to claim 40 or 41, wherein the compression ratio of the foam is> 50%.