CN210052171U

CN210052171U - Optical fingerprint device and electronic equipment

Info

Publication number: CN210052171U
Application number: CN201920910911.6U
Authority: CN
Inventors: 吴宝全; 郭益平
Original assignee: Shenzhen Huiding Technology Co Ltd
Current assignee: Shenzhen Goodix Technology Co Ltd
Priority date: 2019-06-14
Filing date: 2019-06-14
Publication date: 2020-02-11
Anticipated expiration: 2029-06-14

Abstract

An optical fingerprint device and an electronic apparatus, the optical fingerprint device 30 comprising: the optical filter 330, an interconnection pad 332 is formed on the lower surface of the optical filter 330; the optical fingerprint chip 320 is arranged below the optical filter 330, a first bonding pad 321 is arranged on the upper surface of the optical fingerprint chip 320, the optical fingerprint chip 320 is used for receiving a fingerprint optical signal which is reflected or scattered from a human finger and returns, and the fingerprint optical signal is used for detecting fingerprint information of the finger; a flexible circuit board 310 disposed below the optical filter 330, wherein a second pad 311 is disposed on an upper surface of the flexible circuit board 310; the first bonding pad 321 of the optical fingerprint chip 320 is connected to the second bonding pad 311 of the flexible circuit board 310 through the interconnection pad 332.

Description

Optical fingerprint device and electronic equipment

Technical Field

The embodiments of the present application relate to the field of optical fingerprint technology, and more particularly, to an optical fingerprint device and an electronic apparatus.

Background

Along with the high-speed development of the terminal industry, the fingerprint identification technology is more and more emphasized by people, the capacitive fingerprint identification technology cannot meet the requirement of a user on large-area collection, and the optical fingerprint identification technology under the screen is required by the public due to the fact that the display screen is thin and the screen structure is made of a light-transmitting material. Therefore, how to realize the under-screen optical fingerprint identification technology becomes a technical problem to be solved urgently.

SUMMERY OF THE UTILITY MODEL

The embodiment of the application provides an optical fingerprint device and electronic equipment, and optical fingerprint identification under a screen can be realized.

In a first aspect, an optical fingerprint device is provided, wherein an optical filter is formed on a lower surface of the optical filter with an interconnection pad;

the optical fingerprint chip is arranged below the optical filter, a first bonding pad is arranged on the upper surface of the optical fingerprint chip, the optical fingerprint chip is used for receiving a fingerprint optical signal which is reflected or scattered by a human finger and returns, and the fingerprint optical signal is used for detecting fingerprint information of the finger;

the flexible circuit board is arranged below the optical filter, and a second bonding pad is arranged on the upper surface of the flexible circuit board;

the first bonding pad of the optical fingerprint chip is connected with the second bonding pad of the flexible circuit board through the interconnection bonding pad.

In some possible implementations, the flexible circuit board is disposed at a periphery of the optical fingerprint chip.

In some possible implementation manners, a middle region of the flexible circuit board is hollowed out, and the optical fingerprint chip is arranged in the hollowed-out region. In some possible implementations, the flexible circuit board is disposed outside an edge region of the optical fingerprint chip.

In some possible implementations, the first pad is disposed at an edge region of the optical fingerprint chip, and the second pad is disposed at an edge region of the flexible circuit board and near a side of the optical fingerprint chip.

In some possible implementations, the interconnection pad is formed in an edge region of the optical filter and is located above the first pad and the second pad.

In some possible implementation manners, a metal circuit layer is formed on the lower surface of the optical filter, a first protective adhesive is arranged on the surface of the metal circuit layer, and the metal circuit layer forms the interconnection pad through the first protective adhesive.

In some possible implementations, the metal circuit layer is disposed on the lower surface of the optical filter through a transition glue layer.

In some possible implementation manners, the metal circuit layer, the first protective glue layer and the middle area of the transition glue layer are hollowed, the optical fingerprint chip is arranged below the hollowed area to receive a fingerprint optical signal of a finger above the display screen, and the fingerprint optical signal is used for detecting fingerprint information of the finger.

In some possible implementations, the area of the hollowed-out region is larger than the sensing area of the optical fingerprint chip.

In some possible implementations, the first pad is connected to the interconnect pad through a first electrical connection point, and the second pad is connected to the interconnect pad through a second electrical connection point.

In some possible implementations, the first electrical connection point is a gold bump, a copper-tin bump, a solder paste, or an anisotropic conductive adhesive;

the second electric connection point is a gold bump, a copper-tin bump, a soldering paste or anisotropic conductive adhesive.

In some possible implementations, the optical fingerprint device further includes:

and the second protective glue layer is used for coating the first bonding pad, the second bonding pad, the first electric connection point and the second electric connection point.

and the optical component is arranged between the optical filter and the optical fingerprint chip and used for guiding or converging the fingerprint optical signal from the upper part of the display screen to the optical fingerprint chip.

In some possible implementations, the optical assembly includes at least one light blocking layer and a microlens array, the at least one light blocking layer is located below the microlens array and is provided with a plurality of light passing apertures, and the optical fingerprint chip is configured to receive optical signals converged to and passing through the plurality of light passing apertures by the microlens array.

and the retaining wall structure is arranged between the second protective adhesive layer and the optical assembly and used for isolating the optical assembly and the second protective adhesive layer.

In some possible implementations, the retaining wall structure is disposed on an upper surface of the optical fingerprint chip or a lower surface of the first protective adhesive.

In some possible implementations, if the retaining wall structure is disposed on the upper surface of the optical fingerprint chip, the height of the upper surface of the retaining wall structure is lower than the lower surface of the first protective adhesive; or

If retaining wall structure sets up the lower surface of first protection is glued, the height of retaining wall structure's lower surface is higher than the upper surface of optics fingerprint chip.

In some possible implementations, a vertical height from a lower surface of the optical filter to the first pad of the optical fingerprint chip is greater than a vertical height from an upper surface of the optical component to the first pad.

In some possible implementation manners, the upper surface and the lower surface of the optical filter are respectively provided with a coating layer, and the coating layers are used for filtering optical signals of non-target wave bands by penetrating optical signals of target wave bands.

In some possible implementations, the coating layer on the upper surface of the optical filter is between 10 and 50 layers, and the coating layer on the lower surface of the optical filter is between 10 and 50 layers.

In some possible implementations, the target wavelength band is a visible light band.

In some possible implementations, the optical fingerprint device is configured to be disposed below a display screen of an electronic device, and the optical fingerprint chip is configured to receive the fingerprint light signal reflected or scattered from the human finger above the display screen and returned.

In some possible implementations, the display screen is an OLED display screen, and the optical fingerprint chip uses a part of the display units of the OLED display screen as an excitation light source for optical fingerprint detection.

In a second aspect, there is provided an optical fingerprint device comprising: an optical filter;

the flexible circuit board is fixed below the optical filter, the middle area of the flexible circuit board is hollow, and a second bonding pad is arranged on the lower surface of the flexible circuit board;

the optical fingerprint chip is arranged below the hollow area of the flexible circuit board, a first bonding pad is arranged on the upper surface of the optical fingerprint chip, the first bonding pad of the optical fingerprint chip is connected to a second bonding pad of the flexible circuit board, the optical fingerprint chip is used for receiving fingerprint optical signals from fingers, and the fingerprint optical signals are used for detecting fingerprint information of the fingers.

In a possible implementation manner, there is an overlap between an edge area of the flexible circuit board and an edge area of the optical fingerprint chip in a vertical direction, the first pad is disposed at the overlapped edge area of the optical fingerprint chip, and the second pad is disposed at the overlapped edge area of the flexible circuit board.

In one possible implementation, the first pad is connected to the second pad by an electrical connection point.

In one possible implementation, the electrical connection points are gold bumps, copper-tin bumps, solder paste, or anisotropic conductive adhesive.

In one possible implementation, the optical fingerprint device further includes:

and the protective adhesive layer is used for coating the first bonding pad, the second bonding pad and the electric connection point.

In a possible implementation manner, the optical assembly includes at least one light blocking layer and a microlens array, the at least one light blocking layer is located below the microlens array and is provided with a plurality of light passing apertures, and the optical fingerprint chip is configured to receive optical signals converged to the plurality of light passing apertures by the microlens array and passing through the plurality of light passing apertures.

and the retaining wall structure is arranged between the protective glue layer and the optical assembly and used for isolating the optical assembly and the protective glue layer.

In a possible implementation manner, the retaining wall structure is disposed on an upper surface of the optical fingerprint chip or a lower surface of the flexible circuit board.

In a possible implementation manner, if the retaining wall structure is disposed on the upper surface of the overlapping region between the optical fingerprint chip and the flexible circuit board, the height of the upper surface of the retaining wall structure is lower than the lower surface of the flexible circuit board; or

If the retaining wall structure is arranged on the upper surface of the inner side of the overlapping area of the optical fingerprint chip and the flexible circuit board, the height of the upper surface of the retaining wall structure is higher than that of the lower surface of the flexible circuit board;

if the retaining wall structure is arranged on the lower surface of the flexible circuit board, the height of the lower surface of the retaining wall structure is higher than that of the upper surface of the optical fingerprint chip.

In a possible implementation manner, a vertical height from the lower surface of the optical filter to the first pad of the optical fingerprint chip is greater than a vertical height from the upper surface of the optical component to the first pad.

In one possible implementation manner, the flexible circuit board is fixed on the lower surface of the optical filter through an adhesive layer.

In one possible embodiment, the middle region of the adhesive layer is hollowed out.

In a possible implementation manner, the area of the hollowed-out region is larger than the sensing area of the optical fingerprint chip.

In a possible implementation manner, the upper surface and the lower surface of the optical filter are respectively provided with a coating layer, and the coating layers are used for filtering optical signals of non-target wave bands by penetrating optical signals of target wave bands.

In a possible implementation manner, the coating layer on the upper surface of the optical filter is between 10 and 50 layers, and the coating layer on the lower surface of the optical filter is between 10 and 50 layers.

In one possible implementation, the target wavelength band is a visible wavelength band.

In a possible implementation manner, the optical fingerprint device is configured to be disposed below a display screen of an electronic device, and the optical fingerprint chip is configured to receive the fingerprint optical signal reflected or scattered by the human finger above the display screen and returned.

In a possible implementation manner, the display screen is an organic light emitting diode OLED display screen, and the optical fingerprint chip utilizes a part of display units of the OLED display screen as an excitation light source for optical fingerprint detection.

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

a display screen;

and the optical fingerprint device of the first aspect or any possible implementation manner of the first aspect, wherein the optical fingerprint device is disposed below the display screen.

In some possible implementations, the display screen is an organic light emitting diode OLED display screen, and the display screen includes a plurality of OLED light sources, wherein the optical fingerprint device uses at least a portion of the OLED light sources as an excitation light source for optical fingerprint detection.

In a fourth aspect, an electronic device is provided, comprising:

a display screen;

and the optical fingerprint device in the second aspect or any possible implementation manner of the second aspect, wherein the optical fingerprint device is disposed below the display screen.

According to the technical scheme, the interconnection pad is arranged on the lower surface of the optical filter, the pad of the flexible circuit board is electrically connected with the pad of the optical fingerprint chip through the interconnection pad, the optical fingerprint chip is used for receiving fingerprint optical signals reflected or scattered by a user finger from the top of the display screen, the fingerprint optical signals are subjected to photoelectric conversion to obtain corresponding electric signals, the electric signals are further transmitted to the processing circuit through the flexible circuit board, and therefore the processing circuit can perform fingerprint identification on the electric signals.

Drawings

Fig. 1 is a schematic plan view of an electronic device to which the present application may 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 structural diagram of an optical fingerprint device according to an embodiment of the present application.

Fig. 4 is a stacked structure view of a typical optical fingerprint device.

Fig. 5 is a stacked structure view of another exemplary optical fingerprint device.

Fig. 6 is a schematic structural diagram of an optical fingerprint device according to another embodiment of the present application.

FIG. 7 is a schematic block diagram of one implementation of an optical assembly.

FIG. 8 is a schematic block diagram of another implementation of an optical assembly.

Fig. 9 is a schematic structural diagram of an electronic 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 accompanying drawings.

As a common application scenario, the fingerprint identification device provided by the embodiment of the application can be applied to smart phones, tablet computers and other mobile terminals or other terminal devices with display screens; more specifically, in the terminal device described above, the fingerprint recognition device may be embodied as an optical fingerprint device, which may be disposed in a partial area or an entire area below the display screen, thereby forming an Under-screen (Under-display) optical fingerprint system.

Fig. 1 and fig. 2 are schematic diagrams illustrating an electronic device to which an embodiment of the present application may be applied, where fig. 1 is an orientation schematic diagram of an electronic device 10, and fig. 2 is a schematic diagram of a partial cross-sectional structure of the electronic device 10 shown in fig. 1 along a '-a'.

As shown in fig. 1 to 2, the electronic device 10 includes a display screen 120 and an optical fingerprint device 130, wherein the optical fingerprint device 130 is disposed in a partial area below the display screen 120, for example, below a middle area of the display screen. The optical fingerprint device 130 comprises an optical fingerprint sensor, the optical fingerprint sensor comprises a sensing array with a plurality of optical sensing units, and the area where the sensing array is located or the sensing area is the fingerprint detection area 103 of the optical fingerprint device 130. As shown in fig. 1, the fingerprint detection area 103 is located in a display area of the display screen 120.

It should be appreciated that the area of the fingerprint sensing area 103 may be different from the area of the sensing array of the optical fingerprint device 130, for example, by the design of optical path such as lens imaging, reflective folded optical path design or other optical path design such as light converging or reflecting, the area of the fingerprint sensing area 103 of the optical fingerprint device 130 may be larger than the area of the sensing array of the optical fingerprint device 130. In other alternative implementations, the fingerprint sensing area 103 of the optical fingerprint device 130 may be designed to substantially coincide with the area of the sensing array of the optical fingerprint device 130 if optical path guidance is performed, for example, by light collimation.

Therefore, when the user needs to unlock the terminal device or perform other fingerprint verification, the user only needs to press a finger on the fingerprint detection area 103 of the display screen 120, so as to realize fingerprint input. Since fingerprint detection can be implemented in the screen, the electronic device 10 with the above structure does not need to reserve a space on the front surface thereof specially for setting a fingerprint key (such as a Home key), so that a full-screen scheme can be adopted, that is, the display area of the display screen 120 can be substantially extended to the front surface of the whole electronic device 10.

As an alternative implementation, as shown in fig. 2, the optical fingerprint device 130 includes a light detection portion 134 and an optical component 132, where the light detection portion 134 includes the sensing array and a reading circuit and other auxiliary circuits electrically connected to the sensing array, which can be fabricated on a chip (Die) through a semiconductor process, such as an optical imaging chip or an optical fingerprint sensor, the sensing array is specifically a Photo detector (Photo detector) array, which includes a plurality of Photo detectors distributed in an array, and the Photo detectors can be used as the optical sensing units as described above; the optical assembly 132 may be disposed above the sensing array of the light detecting portion 134, and may specifically include a Filter layer (Filter) for filtering out ambient light penetrating the finger, such as infrared light interfering with imaging, and a light guiding layer or light path guiding structure for guiding reflected light reflected from the surface of the finger to the sensing array for optical detection, and other optical elements.

In particular implementations, the optical assembly 132 may be packaged with the same optical fingerprint component as the light detection portion 134. For example, the optical component 132 may be packaged in the same optical fingerprint chip as the optical detection portion 134, or the optical component 132 may be disposed outside the chip where the optical detection portion 134 is located, for example, the optical component 132 is attached to the chip, or some components of the optical component 132 are integrated into the chip.

For example, the light guide layer may specifically be a Collimator (collimater) layer manufactured on a semiconductor silicon wafer, and the collimater unit may specifically be a small hole, and in reflected light reflected from a finger, light perpendicularly incident to the collimater unit may pass through and be received by an optical sensing unit below the collimater unit, and light with an excessively large incident angle is attenuated by multiple reflections inside the collimater unit, so that each optical sensing unit can basically only receive reflected light reflected from a fingerprint pattern directly above the optical sensing unit, and the sensing array can detect a fingerprint image of the finger.

In another embodiment, the light guiding layer or the light path guiding structure 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, and is used to focus the reflected light reflected from the finger to the sensing array of the light detecting portion 134 therebelow, so that the sensing array can perform imaging based on the reflected light, thereby obtaining the fingerprint image of the finger. Optionally, the optical lens layer may further form a pinhole in the optical path of the lens unit, and the pinhole may cooperate with the optical lens layer to enlarge the field of view of the optical fingerprint device, so as to improve the fingerprint imaging effect of the optical fingerprint device 130.

In other embodiments, the light guide layer or the light path guiding structure may also specifically adopt a Micro-Lens (Micro-Lens) layer, the Micro-Lens layer has a Micro-Lens array formed by a plurality of Micro-lenses, which may be formed above the sensing array of the light detecting portion 134 through a semiconductor growth process or other processes, and each Micro-Lens may respectively correspond to one of the sensing units of the sensing array. And another optical film layer, such as a dielectric layer or a passivation layer, may be further formed between the microlens layer and the sensing unit, and more specifically, a light blocking layer having micro holes may be further included between the microlens layer and the sensing unit, where the micro holes are formed between the corresponding microlenses and the sensing unit, and the light blocking layer may block optical interference between adjacent microlenses and the sensing unit, and enable light corresponding to the sensing unit to be converged inside the micro holes through the microlenses and transmitted to the sensing unit through the micro holes for optical fingerprint imaging.

It should be understood that several implementations of the above-mentioned optical path guiding structure may be used alone or in combination, for example, a microlens layer may be further disposed below the collimator layer or the optical lens layer. Of course, when the collimator layer or the optical lens layer is used in combination with the microlens layer, the specific lamination structure or optical path thereof may need to be adjusted according to actual needs.

As an alternative embodiment, the display screen 120 may adopt a display screen having a self-Light Emitting display unit, such as an Organic Light-Emitting Diode (OLED) display screen or a Micro-LED (Micro-LED) display screen. Taking an OLED display screen as an example, the optical fingerprint device 130 may use the display unit (i.e., OLED light source) of the OLED display screen 120 located in the fingerprint detection area 103 as an excitation light source for optical fingerprint detection. When a finger is pressed against the fingerprint detection area 103, the display 120 emits a beam of light to a target finger above the fingerprint detection area 103, the light being reflected at the surface of the finger to form reflected light or scattered light by scattering inside the finger, which is collectively referred to as reflected light for convenience of description in the related patent application. Because ridges (ridges) and valleys (vally) of a fingerprint have different light reflection capacities, reflected light from the ridges and emitted light from the valleys have different light intensities, and the reflected light is received by the sensing array in the optical fingerprint device 130 and converted into corresponding electric signals, i.e., fingerprint detection signals, after passing through the optical assembly; fingerprint image data can be obtained based on the fingerprint detection signal, and fingerprint matching verification can be further performed, so that an optical fingerprint identification function is realized in the electronic device 10. In other embodiments, the optical fingerprint device 130 may also use an internal light source or an external light source to provide an optical signal for fingerprint detection.

It should be appreciated that in particular implementations, the electronic device 10 also includes a transparent protective cover positioned over the display screen 120 and covering the front of the electronic device 10. Because, in the present embodiment, the pressing of the finger on the display screen 120 actually means pressing on the cover plate above the display screen 120 or the surface of the protective layer covering the cover plate.

On the other hand, in some embodiments, the optical fingerprint device 130 may include only one optical fingerprint sensor, where the area of the fingerprint detection area 103 of the optical fingerprint device 130 is small and the location is fixed, so that the user needs to press a finger to a specific location of the fingerprint detection area 103 when performing a fingerprint input, otherwise the optical fingerprint device 130 may not acquire a fingerprint image and the user experience is poor. In other alternative embodiments, the optical fingerprint device 130 may specifically include a plurality of optical fingerprint sensors; the plurality of optical fingerprint sensors may be disposed in the middle area of the display screen 120 side by side in a splicing manner, and sensing areas of the plurality of optical fingerprint sensors jointly form the fingerprint detection area 103 of the optical fingerprint device 130. That is, the fingerprint detection area 103 of the optical fingerprint device 130 may include a plurality of sub-areas, each of which corresponds to a sensing area of one of the optical fingerprint sensors, so that the fingerprint capture area 103 of the optical fingerprint device 130 may be extended to a main area of the middle portion of the display screen, i.e., to a usual finger pressing area, thereby implementing a blind-touch fingerprint input operation. Alternatively, when the number of optical fingerprint sensors is sufficient, the fingerprint detection area 130 may also be extended to half or even the entire display area, thereby enabling half-screen or full-screen fingerprint detection.

Optionally, in some embodiments of the present application, the optical fingerprint device 130 may further include a Circuit board for transmitting signals (e.g., the fingerprint detection signals), for example, the Circuit board may be a Flexible Printed Circuit (FPC). The optical fingerprint sensor may be connected to the FPC and enable electrical interconnection and signal transmission through the FPC with other peripheral circuits or other components in the electronic device. For example, the optical fingerprint sensor may receive a control signal of a processing unit of the electronic device through the FPC, and may also output a fingerprint detection signal (e.g., a fingerprint image) to the processing unit or the control unit of the electronic device through the FPC, or the like.

It is to be noted that, in the embodiments shown below, the same reference numerals are given to the same structures among the structures shown in the different embodiments for the convenience of understanding, and a detailed description of the same structures is omitted for the sake of brevity.

It should be understood that the heights or thicknesses of the various structural members in the embodiments of the present application shown below, as well as the overall thickness of the optical fingerprint device, are illustrative only and should not be construed as limiting the present application in any way.

Fig. 3 is a schematic structural diagram of an optical fingerprint device 30 according to an embodiment of the present application, where the optical fingerprint device 30 is configured to be disposed below a display screen of an electronic device to realize off-screen fingerprint identification, and as shown in fig. 3, the optical fingerprint device 30 includes:

the optical filter 330, an interconnection pad 332 is formed on the lower surface of the optical filter 330;

the optical fingerprint chip 320 is arranged below the optical filter 330, a first bonding pad 321 is arranged on the upper surface of the optical fingerprint chip 320, the optical fingerprint chip 320 is used for receiving a fingerprint optical signal which is reflected or scattered from a human finger and returns, and the fingerprint optical signal is used for detecting fingerprint information of the finger;

a flexible circuit board 310 disposed below the optical filter 330, wherein a second pad 311 is disposed on an upper surface of the flexible circuit board 310;

the first bonding pad 321 of the optical fingerprint chip 320 is connected to the second bonding pad 311 of the flexible circuit board 310 through the interconnection pad 332.

The interconnection bonding pad is arranged on the lower surface of the optical filter, the bonding pad of the flexible circuit board is electrically connected with the bonding pad of the optical fingerprint chip through the interconnection bonding pad, the optical fingerprint chip is used for receiving fingerprint optical signals reflected or scattered by a finger of a user above the display screen, the fingerprint optical signals are subjected to photoelectric conversion to obtain corresponding electric signals, and the electric signals are further transmitted to other peripheral circuits or other elements in electronic equipment through the flexible circuit board, such as a processing circuit, so that the processing circuit can further process the electric signals, such as fingerprint identification.

It should be understood that, in the embodiment of the present application, the optical fingerprint chip 320 may correspond to the light detecting portion 134 shown in fig. 2, which may have an array of a plurality of sensing units 322, and each sensing unit 322 may be used to form one pixel of the captured image.

The filter 330 may be used to filter out interference light affecting fingerprint recognition, for example, ambient light penetrating through a finger, such as infrared light, i.e., the filter 330 may be an infrared filter.

Optionally, in an embodiment of the present application, the optical fingerprint device 30 further includes:

and an optical assembly 340 disposed between the optical filter 330 and the optical fingerprint chip 320 for guiding or converging the fingerprint light signal from above the display screen to the optical fingerprint chip 320.

Optionally, the optical component 340 may correspond to the optical component 132 described in fig. 2, and for specific implementation, reference may be made to the description related to the embodiment shown in fig. 2, and for brevity, description is not repeated here.

Optionally, the optical assembly 340 may specifically include a Filter layer (Filter) for filtering out ambient light penetrating through the finger, a light guiding layer or a light path guiding structure for guiding reflected light reflected from the surface of the finger to the sensor array for optical detection, and other optical elements.

In a specific implementation, the optical component 340 may be packaged in the optical fingerprint sensing chip 320, or the optical component 340 may be disposed outside the optical fingerprint sensing chip 320, for example, the optical component 340 is attached on the optical fingerprint sensing chip 320, or some components of the optical component 320 are integrated in the optical fingerprint sensing chip 320.

In one possible embodiment, as shown in fig. 7, the optical assembly 340 includes: at least one light blocking layer 341 and a microlens array 342;

the at least one light blocking layer 341 is provided with a plurality of light passing small holes;

the micro lens array 342 is disposed above the at least one light blocking layer 341, and configured to converge the light signal to the plurality of light passing holes of the at least one light blocking layer 341, and the light signal is transmitted to the optical fingerprint chip 320 through the plurality of light passing holes of the at least one light blocking layer 341.

The at least one light blocking layer 341 may be formed by a semiconductor process growth or other processes, for example, a non-light-transmissive material film is prepared by atomic layer deposition, sputter coating, electron beam evaporation coating, ion beam coating, and the like, and then photolithography and etching are performed to form a plurality of light-transmissive holes. The at least one light blocking layer 341 may block optical interference between adjacent microlenses, and enable an optical signal corresponding to a pixel unit to be converged inside the light passing aperture through the microlenses and transmitted to the pixel unit in the optical fingerprint chip through the light passing aperture for optical fingerprint imaging.

The microlens array 342 is formed of a plurality of microlenses, which may be formed over the at least one light blocking layer 341 through a semiconductor growth process or other processes, and each microlens may correspond to one of the pixel units 322 of the optical fingerprint sensing chip 320, respectively.

In another possible embodiment, the optical assembly 340 includes a lens assembly 344 having at least one lens group formed by spherical or aspherical optical lenses, and configured to focus the reflected light reflected from the finger to a plurality of pixel units of the optical fingerprint sensing chip below the lens group, so that the plurality of pixel units can be imaged based on the reflected light, thereby obtaining the fingerprint image of the finger. Optionally, the optical lens layer may further form a pinhole in the optical path of the lens unit, and the pinhole may cooperate with the optical lens layer to enlarge the field of view of the fingerprint identification device, so as to improve the fingerprint imaging effect of the fingerprint identification device 20.

Alternatively, as shown in FIG. 8, the lens assembly 344 may be disposed between the optical filter 330 and the optical fingerprint chip 320 by a fixture 345.

Optionally, the fixing device 345 may be a bracket or a lens barrel, one or more optical lenses in the lens assembly 344 are fixed in the lens barrel or the bracket, the lens barrel or the bracket is used to fix the lens assembly 344 above the optical fingerprint sensing chip 320, and the optical signal passes through the lens assembly 344 and then enters the optical fingerprint sensing chip 320. Optionally, when the fixing device 345 is a lens barrel, the fixing device 345 may further include a lens base, the lens barrel and the lens base may be two separate components and may be fixed together by a threaded connection, and the lens base may also be an integrated structure with the lens barrel.

Optionally, the optical assembly 340 may be fixed above the optical fingerprint chip 320 by a light-transmissive adhesive material such as an adhesive 324.

Optionally, in an embodiment of the present application, a metal circuit layer is formed on a lower surface of the optical filter 330, a first protective adhesive 333 is disposed on a surface of the metal circuit layer, and the metal circuit layer forms the interconnection pad 332 through the first protective adhesive 333.

Optionally, the metal circuit layer is connected to the lower surface of the optical filter 330 through a transition glue layer 331.

Since the optical filter is usually manufactured on a transparent substrate material (hereinafter, a glass substrate is taken as an example) such as glass or crystal, a metal circuit layer is directly manufactured on the glass substrate and is easy to peel off, in order to increase the bonding force of the metal circuit layer on the optical filter 330, a transition adhesive layer 331 is firstly manufactured on the lower surface of the optical filter 330, a metal circuit layer is further manufactured on the transition adhesive layer 331, then a first protective adhesive 333 is arranged on the metal circuit layer, and a position of an interconnection pad 332 is formed through the first protective adhesive 333, specifically, a position of the metal circuit layer which is not covered (or covered) by the first protective adhesive 333 is a position of the interconnection pad 332 for connecting the second pad 311 of the flexible circuit board 310 and the first pad 321 of the optical fingerprint chip 320.

It should be noted that the upper surface and the lower surface of the optical filter and other structural members described in the embodiments of the present application are the upper surface and the lower surface in actual use, and in the manufacturing process, there may be a case where the upper surface and the lower surface are inverted, for example, the optical filter is manufactured first, the transition adhesive layer 331 is further manufactured on the upper surface of the optical filter (where the upper surface is the lower surface in actual use), then the metal circuit layer is manufactured on the transition adhesive layer 331, and the first protective adhesive 333 is further manufactured on the metal circuit layer, so as to form the interconnection pad 332.

Optionally, in an embodiment of the present application, the first pad 321 is connected to the interconnection pad 332 through a first electrical connection point 325, and the second pad 311 is connected to the interconnection pad 332 through a second electrical connection point 312.

Optionally, in an embodiment of the present application, the first electrical connection point 325 is an electrical connection structure such as a gold bump, a copper-tin bump, a solder paste, or an Anisotropic Conductive Film (ACF);

similarly, the second electrical connection points 312 are electrically connected structures such as gold bumps, copper-tin bumps, solder paste, or anisotropic conductive adhesive.

Because the flexible circuit board 310 is relatively flexible, the flexible circuit board is generally required to be supported by a reinforcing plate, and the thickness of the reinforcing plate is thicker, generally more than 100 μm, the thickness of the optical fingerprint device is greatly increased, in the embodiment of the present application, the optical filter 330 is a glass substrate material and has a certain supporting effect, the flexible circuit board 310 is connected to the interconnection pad 332 on the optical filter 330 through the second electrical connection point 312, and because the second electrical connection point 312 has a supporting and fixing effect relative to a gold wire, the flexible circuit board 310 can play a role in reinforcing and supporting through the optical filter 330, therefore, in the optical fingerprint device of the embodiment of the present application, the reinforcing plate may not be arranged below the flexible circuit board 310, the overall thickness of the optical fingerprint device can be effectively reduced, and the requirement for thinning electronic equipment can be satisfied.

Alternatively, in some cases, if the assembly space of the electronic device is sufficient, a reinforcing plate may be disposed below the flexible circuit board 310 to provide further support and reinforcement for the flexible circuit board 310.

Optionally, in an embodiment of the present application, the flexible circuit board 310 is disposed at the periphery of the optical fingerprint chip 320. That is, there is no overlap in the vertical direction of the flexible circuit board 310 and the optical fingerprint chip 320.

In a specific embodiment, the middle area of the flexible circuit board is hollowed, and the optical fingerprint chip is arranged in the hollowed area. And the thickness of the flexible circuit board is saved, so that the whole thickness of the optical fingerprint device is reduced. In this case, in a top view, the flexible circuit board is located around the optical fingerprint chip.

In other alternative embodiments, the flexible circuit board may be disposed outside an edge region of the optical fingerprint chip. In this case, the flexible circuit board is located on one side of the optical fingerprint chip in a plan view.

Alternatively, a hole may be formed in one side of the flexible circuit board, and the optical fingerprint chip may be disposed in the hole, or the flexible circuit board may be directly disposed outside an edge area of the optical fingerprint chip.

Optionally, in an embodiment of the present application, the first pad 321 is disposed at an edge region of the optical fingerprint chip 320, and the second pad 311 is disposed at an edge region of the flexible circuit board 310 and near a side of the optical fingerprint chip 320. That is, the first bonding pad 321 and the second bonding pad 311 are respectively disposed at one end of the optical fingerprint chip 320 and the end of the flexible circuit board 310 close to each other. The interconnection pad 332 is formed at an edge region of the filter 330 and is located above the first pad 321 and the second pad 311. Thus, the first pad 321 and the second pad 311 can be electrically connected through the electrical connection point in the vertical direction, which is simple and easy to implement, and can improve the stability and reliability of the electrical connection between the pads, and can better provide reinforcement and support for the flexible circuit board.

and a second protective adhesive layer 335 for covering the first pad 321, the second pad 311, the first electrical connection point 325 and the second electrical connection point 312.

After the first protective paste 333 is formed, a second protective paste layer 335 may be further formed at the electrical connection region to protect and reinforce the pad and the electrical connection point. Specifically, the electrical connection region may be dispensed to form the second protective adhesive layer 335.

Further, in order to avoid overflowing to the area of the optical component 340 when preparing the second protective glue layer 335, the optical fingerprint device 30 further includes:

and a retaining wall structure 334 disposed between the second protective adhesive layer 335 and the optical component 340 for isolating the optical component 340 from the second protective adhesive layer 335.

By arranging the first bonding pad 321 in the edge region of the optical fingerprint chip 320, the second bonding pad 311 of the flexible circuit board 310 is arranged on the flexible circuit board 310 near one side of the optical fingerprint chip 320, and the metal circuit layer and the first protective adhesive layer 331 are arranged in the edge region of the optical filter 330 and above the first bonding pad 321 and the second bonding pad 311, so that the second protective adhesive layer 335 for covering the electrical connection region is also formed in the edge region of the optical filter 330. Further, by arranging the retaining wall structure 334 at a position of the optical filter 330 close to the inner side, it can be avoided that the optical assembly 340 overflows to the lower side of the middle area of the optical filter 330 to affect the fingerprint identification performance when the second protective adhesive layer 335 is prepared.

In some embodiments, the retaining wall structure 334 is disposed inside the first pad 321 and outside the optical component 340, i.e., the retaining wall structure 334 is disposed between the first pad 321 and the optical component 340.

Optionally, the retaining wall structure 334 is disposed on the upper surface of the optical fingerprint chip 320, or the lower surface of the first protective adhesive 333.

For example, the retaining wall structure 334 may be further prepared on the surface of the first protective glue 333 after the first protective glue 333 is prepared, for example, the retaining wall structure 334 may be prepared on the surface of the first protective glue 333 near the inner side. Optionally, the height of the lower surface of the retaining wall structure 334 is higher than the upper surface of the optical fingerprint chip, so as to avoid a cold joint between the first electrical connection point 325 and the first pad 321 when the first electrical connection point 325 is formed subsequently, and a cold joint between the second electrical connection point 312 and the second pad 311 when the second electrical connection point 312 is formed subsequently.

For another example, the retaining wall structure 334 may be prepared on the surface of the optical fingerprint chip 320, for example, the retaining wall structure 334 may be prepared on the surface of the optical fingerprint chip 320 inside the first bonding pad 311 and outside the optical component 340. Optionally, the height of the upper surface of the retaining wall structure 334 is lower than the lower surface of the first protective glue 333, so as to avoid a cold joint between the first electrical connection point 325 and the first pad 321, and a cold joint between the second electrical connection point 312 and the second pad 311.

It should be noted that in the example shown in fig. 3, the second protective glue layer 335 is disposed on two sides of the optical filter, and in a top view, the second protective glue layer 335 may be filled around the optical filter 330, so that a sealed space may be formed between the optical fingerprint chip 320 and the optical filter 330 through the second protective glue layer 335, and an air gap is formed between the optical assembly and the optical filter, which may ensure that the optical filter does not contact the upper surface of the optical assembly when the display screen is pressed or the electronic device falls or collides, and may not affect the stability and performance of fingerprint identification of the optical fingerprint apparatus 30.

Optionally, in an embodiment of the present application, the metal circuit layer, the first protective glue and the middle area of the transition glue layer are hollowed, the optical component 340 and the optical fingerprint chip 320 are disposed below the hollowed area, the optical component 340 is configured to converge a fingerprint optical signal from a finger above the display screen to the optical fingerprint chip 320, and the optical fingerprint chip 320 is configured to receive the fingerprint optical signal and convert the fingerprint optical signal into a corresponding electrical signal, so as to obtain fingerprint information of the finger.

That is to say, the structure for realizing the electrical connection is arranged in the edge area below the optical filter, and the middle area of the optical filter is hollowed out and is used for transmitting the optical signal for fingerprint identification.

In a specific embodiment, the area of the hollowed-out region is larger than the sensing area of the optical fingerprint chip, or the area of the hollowed-out region is larger than the area of the microlens array, so that the optical fingerprint chip can receive enough optical signals for optical fingerprint identification.

Optionally, in an embodiment of the present application, a vertical height from the lower surface of the optical filter 330 to the first pad 321 of the optical fingerprint chip 320 is greater than a vertical height from the upper surface of the optical component 340 to the first pad 321.

That is, the optical assembly 340 is disposed in a hollow region from the optical filter 330 to the optical fingerprint chip 320, and an air gap is formed between the optical assembly 340 and the optical filter 330.

It should be noted that, in an actual product, the thicknesses of the transition glue layer, the first protective glue, the first electrical connection point, the second electrical connection point, and the second protective glue layer are relatively thin, and in the laminated structure shown in fig. 3, in order to better illustrate each structure and a specific electrical connection relationship, the thicknesses of each structure in the laminated structure and the relative thicknesses between each structure are merely illustrative, and should not constitute any limitation to the embodiment of the present application.

Optionally, in an embodiment of the present application, the upper surface and the lower surface of the optical filter 330 are provided with coating layers, and the coating layers are configured to transmit optical signals in a target wavelength band and filter optical signals in a non-target wavelength band.

Optionally, the coating layer is 10 to 50 layers, and the coating layer may include an oxide layer of silicon and an oxide layer of titanium.

Optionally, the target wavelength band is a visible light wavelength band, for example, a wavelength band range of 340nm to 650 nm.

Optionally, the transmittance of the optical filter for the optical signal of the target wavelength band is greater than a first threshold, for example, 90%, and the transmittance for the optical signal of the non-target wavelength band is less than a second threshold, for example, 10%.

Fig. 4 and 5 are stacked structure views of two typical optical fingerprint devices, as shown in fig. 4, in which a first pad 221 of an optical fingerprint chip 220 and a second pad 211 of a flexible circuit board 210 are connected by a gold wire 213, while a reinforcing plate 250 is disposed under the flexible circuit board 210. A filter layer 230 is disposed above the optical fingerprint chip 220, and the filter layer 230 is directly formed on the optical fingerprint chip 220, for example, on the surface of the optical fingerprint chip 220 by evaporation or sputtering process. The optical adhesive layer 243 is disposed on the filter layer 230, and the microlens array 240 is disposed on the optical adhesive layer 243, and the thickness of the optical fingerprint device implemented by the stacked structure shown in fig. 4 is usually over 500 μm, which cannot meet the requirement of electronic equipment for light weight and thinness.

The optical fingerprint device shown in fig. 5 has a substantially identical stack structure to the optical fingerprint device shown in fig. 4, except that the filter layer 230 is deposited on the glass substrate and further adhered above the microlens array 240 by the optical adhesive 260, and compared to the stack structure shown in fig. 4, since the optical filter has a thicker thickness, the stack structure shown in fig. 5 is thicker than the stack structure shown in fig. 4, and cannot meet the requirement of electronic equipment for thinning.

In an actual product, the thickness of the flexible circuit board is generally thicker, which is about 60 to 70 μm, and the overall thickness of the transition adhesive layer, the first protective adhesive layer and the second protective adhesive layer is generally smaller than the thickness of the flexible circuit board, so that the laminated structure of the optical fingerprint device in the embodiment of the present application is equivalent to the thickness of the reinforcing plate and the flexible circuit board which are omitted, compared with the laminated structure of the optical fingerprint device shown in fig. 4 and 5, and the overall thickness is not more than 350 μm, which is beneficial to meeting the requirement of electronic equipment on the thickness.

Fig. 6 is a schematic structural diagram of an optical fingerprint device 40 according to another embodiment of the present application, where the optical fingerprint device 40 is configured to be disposed below a display screen of an electronic device, as shown in fig. 6, the optical fingerprint device 40 includes:

a filter 430;

a flexible circuit board 410; the lower surface of the optical filter 430 is fixed, the middle area of the flexible circuit board 410 is hollow, and the lower surface of the flexible circuit board 410 is provided with a second bonding pad 411;

optics fingerprint chip 420 sets up the regional below of the fretwork of flexible circuit board 410, the upper surface of optics fingerprint chip 420 is provided with first pad 421, optics fingerprint chip 420's first pad 421 is connected to flexible circuit board 410's second pad 411, optics fingerprint chip 420 is used for receiving to come from the fingerprint light signal of display screen top, fingerprint light signal is used for detecting the fingerprint information of finger.

The flexible circuit board 410 is arranged below the optical filter 430, the optical fingerprint chip 420 is arranged below the flexible circuit board 410, so that the electrical connection between a pad on the lower surface of the flexible circuit board 410 and a pad on the upper surface of the optical fingerprint chip 420 can be realized, and the middle area of the flexible circuit board 410 is hollowed out, so that the optical fingerprint chip 420 can receive a fingerprint optical signal reflected or scattered by a finger of a user above a display screen, perform photoelectric conversion on the fingerprint optical signal to obtain a corresponding electrical signal, and further transmit the electrical signal to other peripheral circuits or other elements in electronic equipment, such as a processing circuit, through the flexible circuit board 410, so that the processing circuit further processes the electrical signal, such as fingerprint identification.

The filter 430 may be used to filter out interference light affecting fingerprint recognition, for example, ambient light penetrating through a finger, such as infrared light, i.e., the filter 430 may be an infrared filter.

Optionally, in an embodiment of the present application, the optical fingerprint device 40 further includes:

and an optical assembly 440 disposed between the optical filter 430 and the optical fingerprint chip 420, for guiding or converging the fingerprint light signal from above the display screen to the optical fingerprint chip 420.

Optionally, the optical component 440 may correspond to the optical component 132 illustrated in fig. 2, and for specific implementation, reference may be made to the description related to the embodiment illustrated in fig. 2, and for brevity, description is not repeated here.

It should be understood that the optical assembly 440 may adopt the related structure of the optical assembly 340 in the foregoing embodiments, and specific implementation references to the detailed description in the foregoing embodiments and is not repeated here.

Optionally, the optical assembly 440 may be fixed above the optical fingerprint chip 420 by a light-transmissive adhesive material such as an adhesive glue 424.

Optionally, in an embodiment of the present application, the first pad 421 is connected to the second pad 411 through an electrical connection point 426.

Optionally, in an embodiment of the present application, the electrical connection points 426 are electrical connection structures such as gold bumps, copper-tin bumps, solder paste, or anisotropic conductive adhesive.

Alternatively, in one embodiment of the present application, the flexible circuit board 410 may be fixed to the lower surface of the optical filter 430 by an adhesive layer 436.

Because flexible circuit board 410 is softer, needs the stiffening plate to support, and the stiffening plate thickness is thicker, generally more than 100 μm, greatly increased optical fingerprint device's thickness, in the embodiment of this application, light filter 430 is glass substrate material, has certain supporting role, and flexible circuit board 410 passes through bond line 436 and fixes to light filter 430's lower surface, like this, flexible circuit board 410 can play reinforcement and supporting role through light filter 430, consequently, the optical fingerprint device of the embodiment of this application, flexible circuit board's below can not set up the stiffening plate, can effectively reduce optical fingerprint device's whole thickness, is favorable to satisfying the demand of electronic equipment's frivolousization.

Optionally, in an embodiment of the present application, there is an overlap between an edge area of the flexible circuit board 410 and an edge area of the optical fingerprint chip 420 in a vertical direction, the first pad 421 is disposed at the overlapped edge area of the optical fingerprint chip 421, and the second pad 411 is disposed at the overlapped edge area of the flexible circuit board 410.

Thus, the first bonding pad 411 and the second bonding pad 421 can be electrically connected through the electrical connection point in the vertical direction, and are simple and easy to implement, and the stability and reliability of the electrical connection between the bonding pads can be improved, and the optical fingerprint chip can be better reinforced and supported.

Similarly to the previous embodiment, the upper and lower surfaces of the optical filter and other structural members described in this embodiment are the upper and lower surfaces in actual use, and in the manufacturing process, there may be a case where the upper and lower surfaces are inverted, for example, the optical filter is first manufactured, the adhesive layer 436 is further manufactured on the upper surface of the optical filter (here, the upper surface is the lower surface in actual use), then the flexible circuit board 410 is fixed on the adhesive layer 436, and the second bonding pad 411 of the flexible circuit board 410 and the first bonding pad 421 of the optical fingerprint chip 420 are further connected through the electrical connection point.

and a protective adhesive layer 435 for covering the first pad 421, the second pad 411 and the electrical connection point 426.

After the electrical connection of the first pad 421 and the second pad 411 is achieved, a protective adhesive layer 435 may be further formed at the electrical connection region to protect and reinforce the pads and the electrical connection points. Specifically, the electrical connection region may be dispensed to form the protective adhesive layer 435.

Further, in order to avoid overflowing to the area of the optical assembly 440 when preparing the protective adhesive layer 435, the optical fingerprint device 40 further includes:

and the retaining wall structure 434 is arranged between the protective adhesive layer 435 and the optical assembly 440 and used for isolating the optical assembly 440 from the protective adhesive layer 435.

The overlapped area of the optical fingerprint chip 420 and the flexible circuit board 410 is located at the edge area of the optical filter 430, and the protective adhesive layer 435 for covering the electric connection area is also formed at the edge area of the optical filter 430 by arranging the first bonding pad 421 at the overlapped edge area of the optical fingerprint chip 420 and arranging the second bonding pad 411 of the flexible circuit board 410 at the overlapped edge area of the flexible circuit board 410. Further, by disposing the retaining wall structure 434 at a position close to the inner side of the electrical connection region, it can be avoided that the optical assembly 440 overflows to the lower side of the middle region of the optical filter 430 to affect the fingerprint identification performance when the protective adhesive layer 435 is prepared.

In some embodiments, the retaining wall structure 434 is disposed inside the first pad 421 and outside the optical component 440, i.e., the retaining wall structure 434 is disposed between the first pad 421 and the optical component 440.

Optionally, the retaining wall structure 434 is disposed on the upper surface of the optical fingerprint chip 420 or the lower surface of the flexible circuit board 410.

For example, after the flexible circuit board 410 is fixed on the optical filter 430, the retaining wall structure 434 may be further prepared on the surface of the flexible circuit board 410, for example, the retaining wall structure 434 may be prepared on the surface of the flexible circuit board 410 near the inner side (this structure is not shown in fig. 6). Optionally, the height of the lower surface of the retaining wall structure 434 is higher than the upper surface of the optical fingerprint chip, so as to avoid cold joint between the first bonding pad 421 and the second bonding pad 411 when the electrical connection point 426 is formed subsequently.

For another example, the retaining wall structure 434 may be prepared on the surface of the optical fingerprint chip 420, for example, the retaining wall structure 434 may be prepared on the surface of the optical fingerprint chip 420 inside the first bonding pad 411 and outside the optical assembly 440. In some embodiments, if the dam structure 434 is prepared in the overlapping region of the optical fingerprint chip 420 and the flexible circuit board 410, the height of the upper surface of the dam structure 434 is lower than the lower surface of the flexible circuit board 410 (this structure is not shown in fig. 6) to avoid cold joint between the first pad 421 and the second pad 411 when the electrical connection point 426 is formed subsequently. In other embodiments, if the dam structure 434 is prepared inside the overlapped region of the optical fingerprint chip 420 and the flexible circuit board 410, the height of the upper surface of the dam structure 434 is higher than the lower surface of the flexible circuit board 410 (as shown in fig. 6) to avoid cold joint between the first bonding pad 421 and the second bonding pad 411 when the electrical connection point 426 is formed subsequently.

It should be noted that, in the stacked structure shown in fig. 6, the protective adhesive layer 435 is disposed on two sides of the optical filter 430, and in a top view, the protective adhesive layer 435 may be filled around the optical filter 430, so that a sealed space may be formed between the optical fingerprint chip 420, the optical assembly 440 and the optical filter 430 by the protective adhesive layer 435, and an air gap may be formed between the optical assembly 440 and the optical filter 430, which may ensure that the optical filter does not contact the upper surface of the optical assembly when the display screen is pressed or the electronic device falls or collides, and may not affect the stability and performance of fingerprint identification of the optical fingerprint apparatus 40.

Optionally, in this embodiment of the present application, a middle region between the adhesive layer 436 and the flexible circuit board 410 is hollowed, the optical component 440 and the optical fingerprint chip 420 are disposed below the hollowed region, the optical component 440 is configured to converge a fingerprint optical signal from a finger above the display screen to the optical fingerprint chip 420, and the optical fingerprint chip 420 is configured to receive the fingerprint optical signal and convert the fingerprint optical signal into a corresponding electrical signal, so as to obtain fingerprint information of the finger.

Optionally, in an embodiment of the present application, a vertical height from a lower surface of the optical filter 430 to the first pad 421 of the optical fingerprint chip 420 is greater than a vertical height from an upper surface of the optical component 440 to the first pad 421.

That is, the optical assembly 440 is disposed in a hollow region from the optical filter 430 to the optical fingerprint chip 420, and an air gap is formed between the optical assembly 440 and the optical filter 430.

Optionally, in an embodiment of the present application, the upper surface and the lower surface of the optical filter 430 are provided with coatings, and the coatings are used for transmitting optical signals in a target wavelength band and filtering optical signals in a non-target wavelength band.

Optionally, the target wavelength band is a visible light wavelength band, for example, a wavelength band range of 440nm to 650 nm.

Optionally, the transmittance of the optical filter 430 for the optical signals of the target wavelength band is greater than a first threshold, for example, 90%, and the transmittance for the optical signals of the non-target wavelength band is less than a second threshold, for example, 10%.

In the stacked structure of the optical fingerprint device shown in fig. 6, the optical component 440 and the flexible circuit board 410 are arranged side by side in the horizontal direction, and the flexible circuit board 410 provides a reinforcing effect through the optical filter 430, so that a reinforcing plate is not needed, and the thickness of the optical fingerprint device is not more than 350 μm compared with the thickness of the optical component and the reinforcing plate, which is omitted, and is beneficial to meeting the requirement of electronic equipment on the thickness.

The embodiment of the present application also provides an electronic device, as shown in fig. 9, the electronic device 700 may include a display screen 710 and an optical fingerprint device 720, where the optical fingerprint device 720 is disposed below the display screen 710.

Optionally, the optical fingerprint device 720 may be the optical fingerprint device 30 in the embodiment shown in fig. 3 or the optical fingerprint device 40 in the embodiment shown in fig. 6, and the specific structure may refer to the related description above, which is not repeated herein.

Alternatively, in one embodiment of the present application, the display screen 710 may be embodied as a self-luminous display screen (such as an OLED display screen) and includes a plurality of self-luminous display units (such as OLED pixels or OLED light sources). When the optical image acquisition system is a biometric identification system, a part of the self-luminous display units in the display screen can be used as an excitation light source for biometric identification of the biometric identification system, and is used for emitting optical signals to the biometric detection area for biometric detection.

It should be understood that the specific examples in the embodiments of the present application are for the purpose of promoting a better understanding of the embodiments of the present application and are not intended to limit the scope of the embodiments of the present application.

It is to be understood that the terminology used in the embodiments of the present application and the appended claims is for the purpose of describing particular embodiments only and is not intended to be limiting of the embodiments of the present application. For example, as used in the examples of this application and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

Those of ordinary skill in the art will appreciate that the elements of the examples described in connection with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or combinations of both, and that the components and steps of the examples have been described above generally in terms of their functionality in order to clearly illustrate the interchangeability of hardware and software. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

In the several embodiments provided in the present application, it should be understood that the disclosed system and apparatus may be implemented in other manners. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the units is only one logical division, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may also be an electric, mechanical or other form of connection.

The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiments of the present application.

In addition, functional units in the embodiments 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 integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit.

The integrated unit, if implemented in the form of a software functional unit and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present application may be substantially or partially contributed by the prior art, or all or part of the technical solution may be embodied in a software product, which is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present application. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read-only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk, and other various media capable of storing program codes.

While the invention has been described with reference to specific embodiments, the scope of the invention is not limited thereto, and those skilled in the art can easily conceive various equivalent modifications or substitutions within the technical scope of the invention. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. An optical fingerprint device, wherein the optical fingerprint device is disposed below a display screen of an electronic device, the optical fingerprint device comprising:

the optical filter is provided with an interconnection bonding pad on the lower surface;

the optical fingerprint chip is arranged below the optical filter, a first bonding pad is arranged on the upper surface of the optical fingerprint chip, the optical fingerprint chip is used for receiving a fingerprint optical signal which is reflected or scattered by a human finger above the display screen and returns, and the fingerprint optical signal is used for detecting fingerprint information of the finger;

2. The optical fingerprint device of claim 1, wherein the flexible circuit board is disposed at a periphery of the optical fingerprint chip.

3. The optical fingerprint device according to claim 2, wherein the middle region of the flexible circuit board is hollowed out, and the optical fingerprint chip is disposed in the hollowed-out region.

4. The optical fingerprint device of claim 2, wherein the flexible circuit board is disposed outside an edge region of the optical fingerprint chip.

5. The optical fingerprint device according to any one of claims 2 to 4, wherein the first pad is disposed at an edge region of the optical fingerprint chip, and the second pad is disposed at an edge region of the flexible circuit board and near a side of the optical fingerprint chip.

6. The optical fingerprint device of claim 5, wherein the interconnect pads are formed on an edge region of the filter over the first pads and the second pads.

7. The optical fingerprint device according to any one of claims 1 to 4, wherein a metal circuit layer is formed on a lower surface of the optical filter, a first protective adhesive is disposed on a surface of the metal circuit layer, and the metal circuit layer forms the interconnection pad through the first protective adhesive.

8. The optical fingerprint device of claim 7, wherein the metal circuit layer is disposed on the lower surface of the optical filter through a transition glue layer.

9. The optical fingerprint device according to claim 8, wherein the metal circuit layer, the first protective glue and the transition glue layer are hollowed in the middle area, and the optical fingerprint chip is disposed below the hollowed area to receive the fingerprint optical signal from the human finger above the display screen.

10. The optical fingerprint device of claim 9, wherein the area of the hollowed-out area is larger than the sensing area of the optical fingerprint chip.

11. The optical fingerprint device of claim 7 wherein the first pad is connected to the interconnect pad by a first electrical connection point and the second pad is connected to the interconnect pad by a second electrical connection point.

12. The optical fingerprint device of claim 11,

the first electric connection point is a gold bump, a copper-tin bump, a soldering paste or anisotropic conductive adhesive;

13. The optical fingerprint device of claim 11 or 12, further comprising:

14. The optical fingerprint device of claim 13, further comprising:

15. The optical fingerprint device of claim 14, wherein the optical assembly comprises at least one light blocking layer and a microlens array, the at least one light blocking layer is located below the microlens array and is provided with a plurality of light passing apertures, and the optical fingerprint chip is configured to receive optical signals that are converged to and passed through the plurality of light passing apertures via the microlens array.

16. The optical fingerprint device of claim 14, further comprising:

17. The optical fingerprint device according to claim 16, wherein the retaining wall structure is disposed on an upper surface of the optical fingerprint chip or a lower surface of the first protective adhesive.

18. The optical fingerprint device according to claim 17, wherein if the retaining wall structure is disposed on the upper surface of the optical fingerprint chip, the height of the upper surface of the retaining wall structure is lower than the lower surface of the first protective adhesive; or

19. The optical fingerprint device of any one of claims 14 to 18, wherein a vertical height from a lower surface of the optical filter to the first pad of the optical fingerprint chip is greater than a vertical height from an upper surface of the optical assembly to the first pad.

20. The optical fingerprint device according to any one of claims 1 to 4, wherein the optical filter is provided with a coating layer on the upper surface and the lower surface respectively, and the coating layer is used for transmitting optical signals of target wave bands and filtering optical signals of non-target wave bands.

21. The optical fingerprint device of claim 20, wherein the top surface of the filter is coated with between 10 and 50 layers and the bottom surface of the filter is coated with between 10 and 50 layers.

22. The optical fingerprint device of claim 20, wherein the target wavelength band is a visible wavelength band.

23. The optical fingerprint device of claim 1, wherein the display screen is an OLED display screen, and the optical fingerprint chip utilizes a portion of the display unit of the OLED display screen as an excitation light source for optical fingerprint detection.

24. An optical fingerprint device, comprising:

an optical filter;

25. The optical fingerprint device of claim 24, wherein an edge area of the flexible circuit board and an edge area of the optical fingerprint chip overlap in a vertical direction, the first pad is disposed at the overlapping edge area of the optical fingerprint chip, and the second pad is disposed at the overlapping edge area of the flexible circuit board.

26. The optical fingerprint device of claim 24, wherein the first pad is connected to the second pad by an electrical connection point.

27. The optical fingerprint device of claim 26, wherein the electrical connection points are gold bumps, copper-tin bumps, solder paste, or anisotropic conductive adhesive.

28. The optical fingerprint device of claim 26, further comprising:

29. The optical fingerprint device of claim 28, further comprising:

30. The optical fingerprint device of claim 29, wherein the optical assembly comprises at least one light blocking layer and a microlens array, the at least one light blocking layer is disposed below the microlens array and has a plurality of light passing apertures, and the optical fingerprint chip is configured to receive optical signals that are focused through the plurality of light passing apertures by the microlens array.

31. The optical fingerprint device of claim 30, further comprising:

32. The optical fingerprint device according to claim 31, wherein the retaining wall structure is disposed on an upper surface of the optical fingerprint chip or a lower surface of the flexible circuit board.

33. The optical fingerprint device according to claim 32, wherein if the retaining wall structure is disposed on the upper surface of the overlapping region of the optical fingerprint chip and the flexible circuit board, the height of the upper surface of the retaining wall structure is lower than the lower surface of the flexible circuit board; or

34. The optical fingerprint device of any one of claims 29 to 33, wherein a vertical height from a lower surface of the optical filter to the first pad of the optical fingerprint chip is greater than a vertical height from an upper surface of the optical assembly to the first pad.

35. The optical fingerprint device of any one of claims 24 to 33, wherein the flexible circuit board is fixed to the lower surface of the optical filter by an adhesive layer.

36. The optical fingerprint device of claim 35 wherein an area in the middle of the adhesive layer is hollowed out.

37. The optical fingerprint device of claim 36, wherein the area of the hollowed-out area is larger than the sensing area of the optical fingerprint chip.

38. The optical fingerprint device of any one of claims 24 to 33 wherein the filter has a coating on each of the top and bottom surfaces thereof, the coating being configured to transmit optical signals in a target wavelength band and filter optical signals in a non-target wavelength band.

39. The optical fingerprint device of claim 38, wherein the top surface of the filter is coated with between 10 and 50 layers and the bottom surface of the filter is coated with between 10 and 50 layers.

40. The optical fingerprint device of claim 38, wherein the target wavelength band is a visible wavelength band.

41. The optical fingerprint device of any one of claims 24 to 33, wherein the optical fingerprint device is configured to be disposed below a display screen of an electronic device, and the optical fingerprint chip is configured to receive the fingerprint light signal reflected or scattered from the finger above the display screen.

42. The optical fingerprint device of claim 41, wherein the display screen is an Organic Light Emitting Diode (OLED) display screen, and the optical fingerprint chip utilizes a portion of the display unit of the OLED display screen as an excitation light source for optical fingerprint detection.

43. An electronic device, comprising:

a display screen;

the optical fingerprint device of any one of claims 1 to 23, wherein the optical fingerprint device is disposed below the display screen.

44. The electronic device of claim 43, wherein the display screen is an Organic Light Emitting Diode (OLED) display screen, the display screen comprising a plurality of OLED light sources, and wherein the optical fingerprint device employs at least some of the OLED light sources as excitation light sources for optical fingerprint detection.

45. An electronic device, comprising: a display screen;

the optical fingerprint device of any one of claims 24 to 42, wherein the optical fingerprint device is disposed below the display screen.

46. The electronic device of claim 45, wherein the display screen is an Organic Light Emitting Diode (OLED) display screen, the display screen comprising a plurality of OLED light sources, and wherein the optical fingerprint device employs at least some of the OLED light sources as excitation light sources for optical fingerprint detection.