WO2020243936A1 - Under-screen biometric feature identification apparatus and electronic device - Google Patents

Abstract

Embodiments of the present application provide an under-screen biometric feature identification apparatus and an electronic device capable of performing biometric feature identification on a fingerprint, a palm print, and a face by means of a beam eye lens array. The under-screen biometric feature identification apparatus is suitable for an electronic device having a display screen, and comprises: a beam eye lens array, provided below the display screen, wherein the beam eye lens array comprises multiple beam eye lens units, and each beam eye lens unit comprises a vertically distributed multi-layer micro lens; and an image sensor, provided below the beam eye lens array. Each of the multiple beam eye lens units is used to form on the image sensor, according to a specific ratio, an exact image of a partial region of a target object on the display screen. Images formed on the image sensor by the multiple beam eye lens units are combined to acquire an image of the target object.

Description

Under-screen biometric identification device and electronic equipment Technical field

This application relates to the field of biometric identification, and more specifically, to an under-screen biometric identification device and electronic equipment.

Background technique

There are three main types of under-screen optical fingerprint recognition device technologies that have been disclosed. The first is the under-screen optical fingerprint recognition technology based on periodic micro-hole arrays, which has a large loss of light energy and the fingerprint recognition device needs to be close to the mobile phone screen; the second is the under-screen optical fingerprint recognition based on macro lenses Technology, the thickness of the fingerprint identification device of this scheme is usually thick and bulky, and the intensity of the image received by the fingerprint identification device is not uniform; the third is the under-screen fingerprint identification technology based on the microlens array, and the lens unit of this scheme is too small , The acceptable energy is lower and the exposure time is longer.

Summary of the invention

In view of this, the embodiments of the present application provide an under-screen biometric identification device and electronic equipment. Compared with the periodic micro-hole array solution, it can be directly installed in the electronic equipment without being close to the screen. Frame, keep a safe distance from the display screen of the electronic device, while not affecting the amount of signals such as fingerprints, palm prints, and faces. Compared with the micro-lens solution, the thickness of the biometric identification device under the screen is reduced and separated from the display screen, which can realize large-area biometric identification. Compared with the microlens array solution, the problems of low exposure energy and low optical resolution can be avoided. Therefore, the under-screen biometric identification device of the embodiment of the present application realizes biometric identification such as fingerprints, palm prints, and human faces through the beam eye lens array, and at the same time, it can be ultra-thin, and the imaging quality of biometric identification can be obtained. Great improvement.

In the first aspect, an under-screen biometric identification device is provided, which is suitable for electronic equipment with a display screen, including:

The beam eye lens array is configured to be arranged below the display screen, wherein the beam eye lens array includes a plurality of beam eye lens units, and each of the plurality of beam eye lens units includes a vertical distribution Multi-layer micro lens;

An image sensor arranged under the beam eye lens array;

Wherein, each of the plurality of beam eye lens units is used to image a partial area of the target object on the display screen on the image sensor according to a specific ratio, and the plurality of beam eyes The image formed by the lens unit on the image sensor is used for stitching to obtain an image of the target object.

In a possible implementation manner, the specific ratio is μ, 0.8≤μ≤1.2.

In a possible implementation manner, the imaging of adjacent beam eye lens units among the multiple beam eye lens units on the image sensor has an overlapping area.

In a possible implementation manner, the aperture of the beam eye lens unit is R1, and 3 μm≦R1≦300 μm.

In a possible implementation manner, the distance between the micro lens close to the display screen and the micro lens close to the image sensor in the beam eye lens unit is D1, and 0.61 mm≤D1≤3 mm.

In a possible implementation manner, each layer of microlenses in the multilayer microlens includes at least one microlens or a microlens array.

In a possible implementation manner, the aperture of the microlens in the multilayer microlens is R2, and R2 is less than or equal to 75 μm.

In a possible implementation manner, the microlens in the multilayer microlens is a polygonal microlens whose object-side surface and/or the image-side surface is spherical or aspherical.

In a possible implementation manner, the duty cycle of the microlens in the multilayer microlens is 50%-100%.

In a possible implementation manner, the aperture of a layer of microlens with the largest aperture in the beam eye lens array is used as the distribution period of the beam eye lens unit.

In a possible implementation manner, the multilayer microlenses in the beam eye lens unit are symmetrically distributed.

In a possible implementation manner, the object side surfaces of the microlenses in different layers in the beam eye lens unit have different surface shapes, and/or the microlenses in different layers in the beam eye lens unit The image side surface has different surface shapes.

In a possible implementation manner, the beam eye lens unit sequentially includes from the object side to the image side:

The first micro lens, the second micro lens and the third micro lens;

Wherein, the radius of curvature of the object side surface of the first microlens is k1, the radius of curvature of the image side surface of the first microlens is k2, the radius of curvature of the object side surface of the second microlens is k3, and the The radius of curvature of the image side surface of the second microlens is k4, the radius of curvature of the object side surface of the third microlens is k5, and the radius of curvature of the image side surface of the third microlens is k6, which satisfies the following conditions: k1=- k6, k2=k5, k3=-k4.

In a possible implementation, 0.209≤k1≤0.314, k2 is infinite, and 0.066≤k3≤0.099.

In a possible implementation manner, the multilayer microlenses in the beam eye lens unit are distributed asymmetrically.

In a possible implementation manner, the object side surfaces of the microlenses in different layers in the beam eye lens unit have the same surface shape, and/or the microlenses in different layers in the beam eye lens unit The image side surface has the same shape.

In a possible implementation manner, the beam eye lens unit sequentially includes from the object side to the image side:

The first micro lens, the second micro lens and the third micro lens;

Wherein, the radius of curvature of the object side surface of the first microlens is k1, the radius of curvature of the image side surface of the first microlens is k2, the radius of curvature of the object side surface of the second microlens is k3, and the The radius of curvature of the image side surface of the two microlenses is k4, the radius of curvature of the object side surface of the third microlens is k5, and the radius of curvature of the image side surface of the third microlens is k6, which satisfies the following conditions: 0.104≤k1 ≤0.156, k2 is infinity, 0.077≤k3≤0.115, k4 is infinity, 0.047≤k5≤0.07, k6 is infinity.

In a possible implementation manner, the beam eye lens unit sequentially includes from the object side to the image side:

The first micro lens, the second micro lens and the third micro lens;

Wherein, the radius of curvature of the object side surface of the first microlens is k1, the radius of curvature of the image side surface of the first microlens is k2, the radius of curvature of the object side surface of the second microlens is k3, and the The radius of curvature of the image side surface of the two microlenses is k4, the radius of curvature of the object side surface of the third microlens is k5, and the radius of curvature of the image side surface of the third microlens is k6, which satisfies the following conditions: 0.116≤k1 ≤0.174, -0.67≤k2≤-0.446, 0.068≤k3≤0.102, -0.067≤k4≤-0.045, 0.034≤k5≤0.051, k6 is infinite.

In a possible implementation manner, the microlenses included in each layer of the microlenses in the multilayer microlenses and the pixel units of the image sensor satisfy a one-to-one or one-to-many correspondence relationship.

In a possible implementation manner, a support structure is provided between the microlenses of different layers in the beam eye lens unit to support or fix the microlenses in the beam eye lens unit, and the support structure does not affect all micro lenses. The beam eye lens unit forms an image on the image sensor.

In a possible implementation manner, each layer of microlenses in the multilayer microlens is grown on the surface of a glass substrate or a plastic substrate.

In a possible implementation, a transition layer is provided between the microlens in the multilayer microlens and the glass substrate or the plastic substrate, so that the microlens in the multilayer microlens grows on the Glass substrate or plastic substrate surface.

In a possible implementation manner, the edge area of the microlens in the multilayer microlens is covered with a light shielding layer to eliminate the influence of stray light.

In a possible implementation manner, the light shielding layer covers the edge area of the microlens in the multilayer microlens by more than 1.5 μm.

In a possible implementation, the biometric identification device further includes:

The filter layer is arranged between the display screen and the image sensor, and is used to filter out the light signal of the non-target waveband and transmit the light signal of the target waveband.

In a possible implementation manner, the filter layer is grown on the surface of the image sensor, or the filter layer is disposed between the beam eye lens array and the image sensor, or the filter layer It is arranged between the display screen and the beam eye lens array.

In a possible implementation, the biometric identification device further includes:

A plurality of microlens arrays, wherein each microlens array of the plurality of microlens arrays is arranged on the surface of a pixel unit of the image sensor, and part or all of the pixel unit surfaces of the image sensor are provided with the multiple A microlens array in a microlens array.

In a possible implementation manner, the target object is at least one of a finger, a palm, and a human face.

In a possible implementation manner, the distance between the biometric identification device and the display screen is D2, and 50 μm≦D2≦1000 μm.

In a second aspect, an electronic device is provided, including: a display screen and the first aspect or the biometric identification device in any possible implementation of the first aspect;

Wherein, the distance between the biometric identification device and the display screen is D2, and 50 μm≤D2≤1000 μm.

In a possible implementation manner, the electronic device further includes: a low-pass filter, the low-pass filter is a low-pass filter used for image processing to eliminate the pair of apertures of the beam eye lens unit The influence of the image formed by the beam eye lens unit.

In a possible implementation, 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 The distance between the device and the display screen is D2.

In the embodiment of the present application, the beam eye lens unit in the beam eye lens array can image a partial area of the target object on the display screen on the image sensor according to a specific ratio. The multiple beam eye lens units are formed on the image sensor. The image is used for stitching to obtain the image of the target object, thereby realizing the collection of biometric information such as fingerprints, palm prints, and human faces, and at the same time improving the utilization of the imaging beam.

And by miniaturizing and arraying the beam eye lens unit, imaging such as fingerprints, palm prints, and faces within a certain distance can be realized. Compared with the periodic microhole array solution, it can be separated from the display screen, improve the utilization of the imaging beam, avoid light loss in the vertical direction, and reduce the exposure time of the image sensor. Compared with the micro-lens solution, the biometric identification device under the screen can also reduce the imaging distortion of the entire system, and can realize large-area optical biometric identification. The biometric identification device under the screen can realize erect image splicing and achieve better collimation and imaging quality.

At the same time, the image sensor and the beam eye lens array adopt a separable assembly structure, which is convenient for assembly, and the distance between the two can be flexibly adjusted, so as to obtain a better collimation than the solution of directly growing a microlens array on the surface of the image sensor Sex and image quality. In addition, there is a gap between the beam eye lens array and the display screen, which can be installed and fixed in the middle frame, so that it can be flexibly assembled, and it is convenient to replace the beam eye lens array with appropriate parameters to achieve better imaging effects. In addition, a light-shielding layer is provided in the transparent glass or plastic substrate, and the light-shielding layer covers the edge area of the microlens in the multilayer microlens in the beam eye lens unit, which can reduce the interference of ambient light and stray light on the imaging of the beam eye lens unit. It can also reduce the crosstalk of optical signals between adjacent microlenses, and further obtain better imaging quality and effects.

Description of the drawings

FIG. 1 is a schematic structural diagram of an electronic device to which an embodiment of the present application is applied.

Fig. 2 is a schematic structural diagram of an under-screen biometric identification device provided by an embodiment of the present application.

Fig. 3 is a schematic structural diagram of a beam eye lens unit provided by an embodiment of the present application.

Fig. 4 is a schematic structural diagram of another beam eye lens unit provided by an embodiment of the present application.

Fig. 5 is a schematic structural diagram of another beam eye lens unit provided by an embodiment of the present application.

FIG. 6 is a schematic structural diagram of still another beam eye lens unit provided by an embodiment of the present application.

FIG. 7 is a schematic structural diagram of an electronic device provided by an embodiment of the present application.

Detailed ways

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

As smart terminals enter the era of full screens, the fingerprint collection area on the front of electronic devices is squeezed by the full screen, so under-display (under-screen) biometric identification technology has attracted more and more attention. Under-screen biometric identification technology refers to the installation of under-screen biometric identification devices (such as fingerprint identification modules) below the display screen, so as to realize the biometric identification operation inside the display area of the display screen, without removing the front of the electronic device. The area outside the display area sets the biometric collection area.

Taking the under-screen fingerprint identification technology as an example, the under-screen fingerprint identification technology may include under-screen optical fingerprint identification technology, under-screen ultrasonic fingerprint identification technology or other types of under-screen fingerprint identification technology.

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

It should be understood that the technical solutions of the embodiments of the present application can be applied to various electronic devices, and more specifically, can be applied to electronic devices with display screens. For example, portable or mobile computing devices such as smart phones, laptops, tablet computers, and gaming devices, as well as other electronic devices such as electronic databases, automobiles, and automated teller machines (ATM) in banks, but the embodiments of this application are not limited to this .

It should also be understood that the technical solutions of the embodiments of the present application can perform biometric recognition such as fingerprints, palm prints, and human faces, and can also perform biometric recognition based on the foregoing biometrics, which is not limited in the embodiments of the present application.

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

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 brevity, detailed descriptions of the same components are omitted in different embodiments.

It should be understood that the thickness, length, width and other dimensions of the various components in the embodiments of the application shown in the drawings, as well as the overall thickness, length and width, etc. of the biometric identification device under the screen are only exemplary descriptions, and should not be used here. The application constitutes any restriction.

The electronic device 1 to which the embodiment of the present application can be applied is described below with reference to FIG. 1, and the under-screen biometric identification device is taken as an example of the under-screen fingerprint identification device 20. Of course, other biometric identification such as palm prints and human faces are the same. It is applicable to the electronic device 1, which is not limited in the embodiment of the present application.

Figure 1 is a schematic structural diagram of an electronic device to which the embodiments of the application can be applied. The electronic device 1 includes a display screen 10 and an under-screen fingerprint identification device 20, wherein the under-screen fingerprint identification device 20 is provided in the The partial area below the display screen 10. The under-screen fingerprint recognition device 20 includes an optical fingerprint sensor. The optical fingerprint sensor has a light detection array 400 with a plurality of pixel units 401, and the area where the light detection array 400 is located or its sensing area is the under-screen fingerprint recognition device 20 of the fingerprint detection area 103. As shown in FIG. 1, the fingerprint detection area 103 is located in the display area of the display screen 10. In an alternative embodiment, the under-screen fingerprint identification device 20 can also be arranged in other positions, such as the side of the display screen 10 or the non-transparent area of the edge of the electronic device 1, and the optical path design is used to The light signal of at least a part of the display area of the display screen 10 is guided to the under-screen fingerprint identification device 20 so that the fingerprint detection area 103 is actually located in the display area of the display screen 10.

It should be understood that the area of the fingerprint detection area 103 may be different from the area of the sensing array of the under-screen fingerprint recognition device 20, for example, through a light path design such as lens imaging, a reflective folding light path design, or other light converging or reflecting light paths. The design can make the area of the fingerprint detection area 103 of the fingerprint identification device 20 under the screen larger than the area of the sensing array of the fingerprint identification device 20 under the screen. In other alternative implementations, if the light path is guided by, for example, light collimation, the fingerprint detection area 103 of the under-screen fingerprint identification device 20 can also be designed to be substantially equal to the area of the sensing array of the under-screen fingerprint identification device 20. Consistent.

Therefore, when the user needs to unlock the electronic device or perform other fingerprint verification, he only needs to press his finger on the fingerprint detection area 103 located in the display screen 10 to realize fingerprint input. Since fingerprint detection can be implemented under the screen, the electronic device 1 adopting the above structure does not need to reserve space on the front side for the fingerprint button (such as the Home button), so that a full screen solution can be adopted, that is, the display area of the display screen 10 It can be basically extended to the front of the entire electronic device 1.

As an optional implementation, as shown in FIG. 1, the under-screen fingerprint identification device 20 includes an optical assembly 30 and a light detection part 40, and the light detection part 40 includes the light detection array 400 and the light The reading circuit and other auxiliary circuits that detect the electrical connection of the array can be fabricated on a chip (Die) by a semiconductor process, such as an optical imaging chip or an optical fingerprint sensor. The sensing array is specifically a photodetector (Photodetector) The array includes a plurality of photodetectors distributed in an array, and the photodetectors can be used as the above-mentioned pixel unit; the optical component 30 can be arranged above the sensing array of the photodetection part 40.

In terms of specific implementation, the optical assembly 30 and the light detecting part 40 may be packaged in the same optical fingerprint component. For example, the optical component 30 and the light detecting part 40 may be packaged in the same optical fingerprint chip, or the optical component 30 may be arranged outside the chip where the light detecting part 40 is located, for example, the optical component 30 is attached above the chip, or some components of the optical assembly 30 are integrated into the chip.

It should be understood that, in specific implementation, the electronic device 1 further includes a transparent protective cover 130. The cover may be a glass cover or a sapphire cover, which is located above the display screen 10 and covers the The front of the electronic device 1. Because, in the embodiment of the present application, the so-called finger pressing on the display screen 10 actually refers to pressing the cover plate above the display screen 10 or covering the surface of the protective layer of the cover plate.

On the other hand, in some embodiments, the under-screen fingerprint recognition device 20 may include only one optical fingerprint sensor. At this time, the fingerprint detection area 103 of the under-screen fingerprint recognition device 20 has a small area and a fixed position, so the user When performing fingerprint input, it is necessary to press the finger to a specific position of the fingerprint detection area 103, otherwise the fingerprint recognition device 20 under the screen may not be able to collect fingerprint images, which may result in poor user experience. In other alternative embodiments, the under-screen fingerprint identification device 20 may specifically include multiple optical fingerprint sensors; the multiple optical fingerprint sensors may be arranged side by side under the display screen 10 in a splicing manner, and the multiple The sensing areas of the two optical fingerprint sensors collectively constitute the fingerprint detection area 103 of the under-screen fingerprint identification device 20. In other words, the fingerprint detection area 103 of the under-screen fingerprint identification device 20 may include multiple sub-areas, and each sub-area corresponds to the sensing area of one of the optical fingerprint sensors, so that the fingerprint of the optical fingerprint module 130 The detection area 103 can be extended to the main area of the lower half of the display screen, that is, to the area where the finger is habitually pressed, so as to realize the blind fingerprint input operation. Alternatively, when the number of optical fingerprint sensors is sufficient, the fingerprint detection area 103 can also be extended to half of the display area or even the entire display area, thereby realizing half-screen or full-screen fingerprint detection.

It should be understood that a circuit board 150, such as a flexible printed circuit (FPC), may also be provided under the fingerprint identification device 20 under the screen. The under-screen fingerprint recognition device 20 can be adhered to the circuit board 150 through adhesive, and is electrically connected to the circuit board 150 through bonding pads and metal wires. The optical fingerprint identification device 20 can realize electrical interconnection and signal transmission with other peripheral circuits or other components of the electronic device 1 through the circuit board 150. For example, the under-screen fingerprint recognition device 20 can receive the control signal of the processing unit of the electronic device 1 through the circuit board 150, and can also output the fingerprint detection signal from the under-screen fingerprint recognition device 20 to the electronic device 1 through the circuit board 150. Unit or control unit, etc.

It should be noted that the optical fingerprint device in the embodiments of the present application may also be referred to as an optical fingerprint recognition module, a fingerprint recognition device, a fingerprint recognition module, a fingerprint module, a fingerprint acquisition device, etc., and the above terms can be replaced with each other.

It should be noted that when the display screen 10 is a display screen with a self-luminous display unit, such as an OLED display screen or a Micro-Light-Emitting Diode (Micro-LED) display screen. Taking an OLED display screen as an example, the under-screen fingerprint identification device 20 may use the display unit (ie, OLED light source) of the OLED display screen 10 located in the fingerprint detection area 103 as an excitation light source for optical fingerprint detection. The display screen 10 emits a beam of light to the target finger 140 above the fingerprint detection area 103, and the light is reflected on the surface of the finger 140 to form reflected light or scattered inside the finger 140 to form scattered light. In related patent applications For ease of description, the above reflected light and scattered light are collectively referred to as reflected light. Since the ridge and valley of the fingerprint have different light reflection capabilities, the reflected light from the fingerprint ridge and the reflected light from the fingerprint ridge have different light intensities. After the reflected light passes through the optical component 30, it is screened. The light detection array 400 in the lower fingerprint identification device 20 receives and converts it 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, so that The electronic device 1 realizes the optical fingerprint recognition function.

When the display screen 10 is a display screen without a self-luminous display unit, such as a liquid crystal display screen or other passive light-emitting display screens, a backlight module needs to be used as the light source of the display screen 10. Taking a liquid crystal display with a backlight module and a liquid crystal panel as an example, in order to support fingerprint detection under the liquid crystal display, as shown in FIG. 1, the display 10 includes a liquid crystal panel 110 and a backlight module 120. The backlight module is used to send a light signal to the liquid crystal panel, and the liquid crystal panel 110 includes a liquid crystal layer and a control circuit for controlling the deflection of the liquid crystal to transmit the light signal. The electronic device 1 may also include an excitation light source 160 for optical fingerprint detection. The under-screen fingerprint identification device 20 is arranged under the backlight module 120. When the finger 140 is pressed against the fingerprint detection area 103, the The light source 160 emits excitation light 111 to the target finger 140 above the fingerprint detection area 103, and the excitation light 111 is reflected on the surface of the finger 140 to form the first reflected light 151 of the fingerprint ridge 141 and the second reflected light 152 of the fingerprint ridge 142 , The first reflected light 151 and the second reflected light 152 need to pass through the liquid crystal panel 110 and the backlight module 120, and then pass through the optical assembly 30, and are received by the light detection array 400 in the under-screen fingerprint identification device 20 and converted into fingerprints Heartbeat.

In one implementation, the under-screen fingerprint identification device 20 can use a periodic micro-hole array to transmit light to the sensing array. This solution has a large loss of light energy and a long sensor exposure time, in order to obtain better fingerprint signals. The under-screen fingerprint identification device 20 needs to be close to the mobile phone screen.

In another implementation manner, the under-screen fingerprint identification device 20 may use microlens to transmit light to the sensing array. The under-screen fingerprint identification device 20 is generally thicker and larger in volume. The intensity of the fingerprint image received by the fingerprint identification device 20 is not uniform.

In another implementation manner, the under-screen fingerprint identification device 20 may use a microlens array to transmit light to the sensing array. In this solution, the lens unit is too small, the energy that can be received is lower, and the exposure time is longer.

It should be understood that when the ordinary lens unit system forms a real image, such as a mobile phone, a single-lens reflex camera, and a sports camera, it becomes an inverted image. The beam eye lens array is formed by a microlens unit array that can image in a positive phase, and can image a specific area of the object in a positive image.

In order to solve the above-mentioned various problems, embodiments of the present application provide a biometric identification device. The biometric identification device can be arranged under the display screen, and the biometric positive image can be imaged on the image sensor through the beam eye lens array. Biometric recognition can be ultra-thin, and the imaging quality of biometric recognition can be greatly improved. Specifically, as shown in Figure 2.

FIG. 2 is a schematic structural diagram of an under-screen biometric identification device 200 according to an embodiment of the present application, which is suitable for electronic equipment with a display screen 10.

It should be noted that, when the biometric feature is a fingerprint, the off-screen biometric identification device 200 may be the above-mentioned under-screen fingerprint identification device 20 in FIG. 1.

Specifically, as shown in FIG. 2, the off-screen biometric identification device 200 may include:

The beam eye lens array 210 is configured to be arranged under the display screen 10, wherein the beam eye lens array 210 includes a plurality of beam eye lens units 211, and each of the plurality of beam eye lens units 211 is a beam eye lens The unit 211 includes vertically distributed multilayer microlenses 2110;

The image sensor 220 is arranged under the beam eye lens array 210;

Wherein, each of the plurality of beam eye lens units 211 is used to image a partial area of the target object on the display screen 10 on the image sensor 220 according to a specific ratio. The images formed by the plurality of beam eye lens units 211 on the image sensor 220 are used for stitching to obtain an image of the target object.

For example, each of the plurality of beam eye lens units 211 includes 2-5 layers of microlenses 2110 distributed vertically. FIG. 2 is an example in which each of the plurality of beam-eye lens units 211 includes three layers of microlenses 2110 distributed vertically, and does not limit the embodiment of the present application.

Optionally, the specific ratio is μ, 0.8≤μ≤1.2.

It should be noted that when the specific ratio μ is less than 1, the images formed by the multiple beam eye lens units 211 on the image sensor 220 can be overlapped and stitched, that is, the formed images have certain Overlapping area. When the specific ratio μ is equal to 1, the images formed by the plurality of beam eye lens units 211 on the image sensor 220 can be seamlessly stitched, that is, each beam eye lens unit 211 is used to combine all the images The partial area of the target object on the display screen 10 is imaged on the image sensor 220 according to a 1:1 erect image, and the imaging effect is the best in this case. When the specific ratio μ is greater than 1, the images formed by the plurality of beam eye lens units 211 on the image sensor 220 can be stitched together, that is, the formed images have a certain interval.

In the embodiment of the present application, the material of the beam eye lens array 210 may be plastic or glass. And the production of the beam eye lens array 210 can be achieved through a thermal reflow process, a stamping process, and a grayscale photolithography process.

The beam eye lens array 210 and the image sensor 220 can be assembled by fixing the ultra-thin double-sided tape frame. It may also be other adhesives with adhesive properties, as long as the image sensor 220 and the beam eye lens array 210 can be frame-attached and fixed, which is not limited in this embodiment.

In the embodiment of the present application, the splicing method of the images formed by the plurality of beam eye lens units 211 on the image sensor 220 may be physical splicing.

It should be noted that, the display screen 10 described in the embodiment of the present application may be, for example, a liquid crystal display (LCD) or an organic light-emitting diode (OLED) display.

Optionally, the optical assembly 30 in FIG. 1 may include the beam eye lens array 210.

Optionally, the light detection array 400 in FIG. 1 may be the image sensor 220.

Optionally, the image sensor 220 may be a complementary metal oxide semiconductor (Complementary Metal Oxide Semiconductor, CMOS) image sensor.

Optionally, the target object is at least one of a finger, a palm, and a human face. Of course, the target object may also be some other biological feature information, which is not limited in this application.

Optionally, in the embodiment of the present application, adjacent beam eye lens units 211 of the plurality of beam eye lens units 211 have overlapping areas in imaging on the image sensor 220. Of course, this overlapping area will be relatively small, and under the premise that the unevenness of the illuminance of the splicing area can be reduced, the distribution period of the beam eye lens unit 211 in the beam eye lens array 210 will not be greatly affected.

In other words, the adjacent beam eye lens units 211 of the plurality of beam eye lens units 211 can image each other in the imaging area of each other, so that the unevenness of the illuminance of the splicing area can be reduced.

Optionally, the aperture of the beam eye lens unit 211 is R1, and 3 μm≦R1≦300 μm.

Optionally, in the embodiment of the present application, the aperture of a layer of microlenses with the largest aperture in the beam eye lens array 210 is used as the distribution period of the beam eye lens unit 211.

Optionally, as shown in FIG. 2, the distance between the microlens close to the display screen 10 and the microlens close to the image sensor 220 in the beam eye lens unit 211 is D1, 0.61mm≤D1≤3mm .

Optionally, each layer of microlenses in the multilayer microlens 2110 includes at least one microlens or a microlens array. FIG. 2 only takes one microlens in each layer of the multilayer microlens 2110 as an example for illustration, and does not limit the application.

Optionally, the aperture of the microlens in the multilayer microlens 2110 is R2, R2≤75 μm.

It should be noted that the aperture of the microlens in the multilayer microlens 2110 needs to meet the requirements of biometric sampling. For example, when fingerprint collection is performed, R2 generally needs to be less than or equal to 75 μm. In other words, the spatial sampling period of the image sensor 220 needs to meet the biometric sampling requirement. For example, when fingerprint collection is performed, the spatial sampling period of the image sensor 220 generally needs to be less than or equal to 75 μm.

Optionally, the microlenses in the multilayer microlens 2110 are polygonal microlenses whose object-side surface and/or image-side surface are spherical or aspherical.

The above-mentioned polygon may be, for example, a quadrilateral or a hexagon, of course, it may also be other polygons. Compared with a circular microlens, a polygonal microlens may have a larger duty ratio in the beam eye lens unit 211. For example, when the microlenses in the multilayer microlens 2110 adopt a square arrangement, the duty ratio of the microlenses can be as high as 100%.

For example, the microlens in the multilayer microlens 2110 is a polygonal microlens whose object side surface is spherical. For another example, the microlens in the multilayer microlens 2110 is a polygonal microlens with an aspheric surface on the object side. For another example, the microlens in the multilayer microlens 2110 is a polygonal microlens whose image side surface is spherical. For another example, the microlens in the multilayer microlens 2110 is a polygonal microlens whose image side surface is aspherical.

The spherical microlens may be, for example, a convex lens, and the aspherical microlens may be, for example, a plane lens.

Optionally, the surface shape of the object side surface and the image side surface of the microlens in the multilayer microlens 2110 may be the same or different. The shape of the object side surface and the image side surface of the microlens in the multilayer microlens 2110 may be the same or different.

It should be noted that the object side surface of the microlens in the multilayer microlens 2110 may be the surface on the side close to the display screen 10, and the image side surface of the microlens in the multilayer microlens 2110 may be The surface on the side close to the image sensor 220.

Optionally, the duty cycle of the microlens in the multilayer microlens is 50%-100%. That is, in the beam eye lens unit 211, the duty ratio of the microlenses of each layer may be 50% to 100%. In the beam eye lens unit 211, the duty ratios of the micro lenses of different layers may be the same or different.

Optionally, in the embodiment of the present application, the multilayer microlenses 2110 in the beam eye lens unit 211 are symmetrically distributed.

Optionally, the object side surfaces of the microlenses in different layers in the beam eye lens unit 211 have different surface shapes, and/or the image side surfaces of the microlenses in different layers in the beam eye lens unit 211 Have different face shapes.

In other words, the object side surfaces of the microlenses in different layers in the beam eye lens unit 211 have different orientations, and/or, the image side surfaces of the microlenses in different layers in the beam eye lens unit 211 have Different orientations.

Optionally, in the case where the multi-layer microlenses 2110 in the beam eye lens unit 211 are symmetrically distributed, the beam eye lens unit 211 may sequentially include from the object side to the image side:

The first microlens 51, the second microlens 52 and the third microlens 53;

Wherein, the curvature radius of the object side surface of the first microlens 51 is k1, the curvature radius of the image side surface of the first microlens 51 is k2, and the curvature radius of the object side surface of the second microlens 52 is k3, The radius of curvature of the image side surface of the second microlens 52 is k4, the radius of curvature of the object side surface of the third microlens 53 is k5, and the radius of curvature of the image side surface of the third microlens 53 is k6, which satisfies The following conditions: k1=-k6, k2=k5, k3=-k4.

Optionally, 0.209≤k1≤0.314, k2 is infinity, and 0.066≤k3≤0.099.

That is, the image-side surface of the first microlens 51 and the object-side surface of the third microlens 53 may be aspherical, for example, a plane lens.

For example, as shown in FIG. 3, the beam eye lens unit 211 includes, from the object side to the image side, a first microlens 51, a second microlens 52, and a third microlens 53, wherein the first microlens 51, the second microlens The microlens 52 and the third microlens 53 are symmetrically distributed, k1=-k6, k2=k5, k3=-k4, and k1=2.62E-01, k2=infinity, k3=8.23E-02, k4=-8.23 E-02, k5=infinity, k6=-2.62E-01. On the imaging optical path of the beam eye lens unit 211, specific optical path parameters may be shown in Table 1 below.

Table 1

It should be noted that H-K9L is glass, that is, the display screen, the first microlens, the second microlens, and the third microlens can be made of glass materials, of course, they can also be made of other transparent materials. This application does not limit this.

Optionally, in the imaging optical path shown in FIG. 3, a plane mirror may be provided at position A and/or position B (position A and position B are respectively located on both sides of the second microlens 52), for example, as shown in FIG. 4 As shown, a flat mirror 54 is set at the A position. In this case, on the imaging optical path of the beam eye lens unit 211, specific optical path parameters may be shown in Table 2 below.

Table 2

Optionally, in the embodiment of the present application, the multilayer microlenses 2110 in the beam eye lens unit 211 are distributed asymmetrically.

Optionally, the object side surfaces of the microlenses in different layers in the beam eye lens unit 211 have the same surface shape, and/or the image side surfaces of the microlenses in different layers in the beam eye lens unit 211 Have the same face shape.

In other words, the object side surfaces of the microlenses in different layers in the beam eye lens unit 211 have the same orientation, and/or, the image side surfaces of the microlenses in different layers in the beam eye lens unit 211 have The same orientation.

Optionally, in the case where the multilayer microlenses 2110 in the beam eye lens unit 211 are distributed asymmetrically, the beam eye lens unit 211 includes in order from the object side to the image side:

The first microlens 51, the second microlens 52 and the third microlens 53;

Wherein, the curvature radius of the object side surface of the first microlens 51 is k1, the curvature radius of the image side surface of the first microlens 51 is k2, and the curvature radius of the object side surface of the second microlens 52 is k3, The radius of curvature of the image side surface of the second microlens 52 is k4, the radius of curvature of the object side surface of the third microlens 53 is k5, and the radius of curvature of the image side surface of the third microlens 53 is k6, which satisfies The following conditions: 0.104≤k1≤0.156, k2 is infinity, 0.077≤k3≤0.115, k4 is infinity, 0.047≤k5≤0.07, k6 is infinity.

That is, the image-side surface of the first microlens 51, the image-side surface of the second microlens 52, and the image-side surface of the third microlens 53 may be aspherical, for example, a plane lens, and the first The image side surface and the object side surface of the microlens 51, the second microlens 52, and the third microlens 53 have the same orientation.

For example, as shown in FIG. 5, the beam eye lens unit 211 includes a first microlens 51, a second microlens 52, and a third microlens 53, from the object side to the image side. Among them, the first microlens 51, the second microlens The image side surface and the object side surface of the microlens 52 and the third microlens 53 have the same orientation, and k1=1.30E-01, k2=infinity, k3=9.57E-02, k4=infinity, k5=5.83E- 02, k6=infinity. On the imaging optical path of the beam eye lens unit 211, specific optical path parameters may be shown in Table 3 below.

table 3

Optionally, in the case of asymmetrical distribution of the multilayer microlenses 2110 in the beam eye lens unit 211, an ultra-short optical path design can be implemented, for example, the length of the under-screen optical path part is less than 0.78 mm. Specifically, the beam eye lens unit 211 sequentially includes from the object side to the image side:

The first microlens 51, the second microlens 52 and the third microlens 53;

Wherein, the curvature radius of the object side surface of the first microlens 51 is k1, the curvature radius of the image side surface of the first microlens 51 is k2, and the curvature radius of the object side surface of the second microlens 52 is k3, The radius of curvature of the image side surface of the second microlens 52 is k4, the radius of curvature of the object side surface of the third microlens 53 is k5, and the radius of curvature of the image side surface of the third microlens 53 is k6, which satisfies The following conditions: 0.116≤k1≤0.174, -0.67≤k2≤-0.446, 0.068≤k3≤0.102, -0.067≤k4≤-0.045, 0.034≤k5≤0.051, k6 is infinite.

For example, as shown in FIG. 6, the beam eye lens unit 211 sequentially includes a first microlens 51, a second microlens 52, and a third microlens 53, from the object side to the image side, where k1=1.45E-01, k2 = -5.58E-01, k3 = 8.46E-02, k4 = -5.60E-02, k5 = 4.24E-02, k6 = infinity, the second microlens 52 consists of microlenses X and The microlens Y is combined, the radius of curvature of the connecting surface of the microlens X and the microlens Y is infinity, the thickness of the microlens X in the second microlens 52 is 1.20E-01mm, and the thickness of the microlens Y is 6.96E-02mm . On the imaging optical path of the beam eye lens unit 211, specific optical path parameters may be shown in Table 4 below.

Table 4

It should be noted that, in the embodiments of the present application, the embodiments of the present application can be implemented by changing the refractive material, changing the radius of curvature of the lens, and using more lenses.

Optionally, in the embodiment of the present application, the microlenses included in each layer of the microlenses in the multilayer microlens 2110 and the pixel units of the image sensor 220 satisfy a one-to-one or one-to-many correspondence relationship. That is, the pixel density of the image sensor 220 under the beam eye lens array 210 can be flexibly set according to actual requirements, or the image sensor 220 with a specific pixel density can be flexibly selected according to actual requirements.

It should be noted that the pixel unit of the image sensor 220 corresponding to each beam eye lens unit 211 needs to meet the imaging requirements of the beam eye lens unit 211.

Optionally, in the embodiment of the present application, a supporting structure 2111 is provided between the microlenses of different layers in the beam eye lens unit 211 to support or fix the micro lenses in the beam eye lens unit 211. The supporting structure 2111 does not affect the imaging of the beam eye lens unit 211 on the image sensor 220.

Optionally, the supporting structure 2111 may be disposed in the peripheral area of the beam eye lens unit 211, and only serves to support or fix the micro lens in the beam eye lens unit 211, and does not affect the beam eye The optical signal transmission in the lens unit 211 will not affect the imaging of the beam eye lens unit 211 on the image sensor 220.

Optionally, in the embodiment of the present application, each layer of microlenses in the multilayer microlens 2110 is grown on the surface of a glass substrate or a plastic substrate.

Optionally, a transition layer is provided between the microlenses in the multilayer microlens 2110 and the glass substrate or plastic substrate, so that the microlenses in the multilayer microlens 2110 grow on the glass substrate or Plastic substrate surface.

Optionally, the edge area of the microlens in the multilayer microlens 2110 is covered with a light-shielding layer to eliminate the influence of stray light.

For example, the light shielding layer covers the edge area of the microlens in the multilayer microlens by more than 1.5 μm.

Optionally, the light-shielding layer may be disposed above or below the transition layer, which is not limited in this application.

Optionally, in the embodiment of the present application, as shown in FIG. 2, the biometric identification device 200 further includes:

The filter layer 230 is disposed between the display screen 10 and the image sensor 220, and is used to filter out the light signal of the non-target waveband and transmit the light signal of the target waveband.

Optionally, the filter layer 230 is grown on the surface of the image sensor 220, or the filter layer 230 is disposed between the beam eye lens array 210 and the image sensor 220, or the filter layer 230 is arranged between the display screen 10 and the beam eye lens array 210.

It should be noted that the filter layer 230 may be one or more filters or optical filter coatings. For example, the filter layer 230 may be an infrared cut filter.

Optionally, the filter layer 230 is not limited to being provided by a growth process, and may also be provided on the image sensor 220 through other processes, such as an evaporation process, which is not limited in this embodiment.

It should be understood that the filter layer 230 may be used to reduce undesired background light in the collection of biological features, so as to improve the optical sensitivity of the image sensor to the received light. The filter layer 230 can specifically be 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, a human finger absorbs most of the energy of light with a wavelength lower than 580nm. If the filter layer 230 can be designed to filter light with a wavelength from 580nm to infrared, the influence of ambient light on the imaging effect in biological feature collection can be greatly reduced. .

Optionally, in this embodiment of the present application, the biometric identification device 200 further includes:

A plurality of microlens arrays 240, wherein each microlens array of the plurality of microlens arrays 240 is disposed on the surface of a pixel unit of the image sensor 220, and part or all of the pixel units of the image sensor 220 are disposed on the surface There is a micro lens array among the plurality of micro lens arrays 240.

That is to say, in the embodiment of the present application, a microlens array may be provided on part or all of the pixel unit surface of the image sensor 220 to increase the light-gathering effect of the image sensor 220, thereby reducing the exposure time.

Optionally, in the embodiment of the present application, as shown in FIG. 2, the distance between the biometric identification device 200 and the display screen 10 is D2, and 50 μm≦D2≦1000 μm. That is to say, the biometric identification device 200 can be installed in a place 50 μm to 1000 μm below the display screen 10, which meets the safety distance between the biometric identification device 200 and the display screen 10, and is not caused by vibration or falling. The display screen 10 is damaged and the biometric identification device 200 is damaged.

Optionally, in the embodiment of the present application, the biometric identification device 200 may be fixed on the middle frame of the electronic device. For example, the biometric identification device 200 can be fixed on the middle frame of an electronic device such as a mobile phone.

As shown in FIG. 7, an embodiment of the present application further provides an electronic device 300, which may include a display screen 10 and the under-screen biometric identification device 200 of the above-mentioned application embodiment, wherein the biometric identification device The distance between 200 and the display screen 10 is D2, 50 μm≦D2≦1000 μm.

Optionally, the electronic device 300 further includes a low-pass filter 310, the low-pass filter 310 is a low-pass filter used for image processing to eliminate the effect of the beam eye lens unit diaphragm on the The influence of the image formed by the beam eye lens unit 211.

Optionally, the electronic device 300 further includes: a middle frame 320, and the under-screen biometric identification device 200 is assembled to the bottom of the display screen 10 through the middle frame 320, so that the under-screen biometric identification The distance between the device 200 and the display screen 10 is D2.

Of course, the electronic device 300 may also include other components or modules such as a processor, a memory, and a power supply, which are not limited in this application.

In the embodiment of the present application, the beam eye lens unit in the beam eye lens array can image a partial area of the target object on the display screen on the image sensor according to a specific ratio. The multiple beam eye lens units are formed on the image sensor. The image is used for stitching to obtain the image of the target object, thereby realizing the collection of biometric information such as fingerprints, palm prints, and human faces, and at the same time improving the utilization of the imaging beam.

And by miniaturizing and arraying the beam eye lens unit, imaging such as fingerprints, palm prints, and faces within a certain distance can be realized. Compared with the periodic microhole array solution, it can be separated from the display screen, improve the utilization of the imaging beam, avoid light loss in the vertical direction, and reduce the exposure time of the image sensor. Compared with the micro-lens solution, the biometric identification device under the screen can also reduce the imaging distortion of the entire system, and can realize large-area optical biometric identification. The biometric identification device under the screen can realize erect image splicing and achieve better collimation and imaging quality.

At the same time, the image sensor and the beam eye lens array adopt a separable assembly structure, which is convenient for assembly, and the distance between the two can be flexibly adjusted, so as to obtain a better collimation than the solution of directly growing a microlens array on the surface of the image sensor Sex and image quality. In addition, there is a gap between the beam eye lens array and the display screen, which can be installed and fixed in the middle frame, so that it can be flexibly assembled, and it is convenient to replace the beam eye lens array with appropriate parameters to achieve better imaging effects. In addition, a light-shielding layer is provided in the transparent glass or plastic substrate, and the light-shielding layer covers the edge area of the microlens in the multilayer microlens in the beam eye lens unit, which can reduce the interference of ambient light and stray light on the imaging of the beam eye lens unit. It can also reduce the crosstalk of optical signals between adjacent microlenses, and further obtain better imaging quality and effects.

It should be understood that the specific examples in the embodiments of the present application are only intended 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 of "a", "above" and "the" used in the embodiments of this application and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.

A person of ordinary skill in the art may be aware that, in combination with the examples described in the embodiments disclosed herein, the units can be implemented by electronic hardware, computer software, or a combination of both, in order to clearly illustrate the interchangeability of hardware and software. In the above description, the composition and steps of each example have been described generally in terms of function. Whether these functions are executed by hardware or software depends on the specific application and design constraint conditions of the technical solution. Professionals and technicians can use different methods for each specific application to implement the described functions, 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 illustrative. For example, the division of the units is only a logical function division, and there may be other divisions in actual implementation, for example, multiple units or components can be combined or It can be integrated into another system, or some features can be ignored or not implemented. In addition, the displayed or discussed mutual coupling or direct coupling or communication connection may be indirect coupling or communication connection 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 they 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, the functional units in the various embodiments of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units may be integrated into one unit. The above-mentioned integrated unit can be implemented in the form of hardware or software functional unit.

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

The above are only specific implementations of this application, but the protection scope of this application is not limited to this. Anyone familiar with the technical field can easily think of various equivalents within the technical scope disclosed in this application. Modifications or replacements, these modifications or replacements shall be covered within the protection scope of this application. Therefore, the protection scope of this application shall be subject to the protection scope of the claims.

Claims (31)

A biometric identification device, characterized in that it is suitable for electronic equipment with a display screen, and includes: The beam eye lens array is configured to be arranged below the display screen, wherein the beam eye lens array includes a plurality of beam eye lens units, and each of the plurality of beam eye lens units includes a vertical distribution Multi-layer micro lens; An image sensor arranged under the beam eye lens array; Wherein, each of the plurality of beam eye lens units is used to image a partial area of the target object on the display screen on the image sensor according to a specific ratio, and the plurality of beam eyes The image formed by the lens unit on the image sensor is used for stitching to obtain an image of the target object. The biometric identification device according to claim 1, wherein the specific ratio is μ, 0.8≤μ≤1.2. The biometric identification device according to claim 1 or 2, wherein adjacent ones of the plurality of beam eye lens units have overlapping areas in imaging on the image sensor. The biometric identification device according to any one of claims 1 to 3, wherein the aperture of the beam eye lens unit is R1, and 3 μm≦R1≦300 μm. The biometric identification device according to any one of claims 1 to 4, wherein the distance between the micro lens close to the display screen and the micro lens close to the image sensor in the beam eye lens unit It is D1, 0.61mm≤D1≤3mm. The biometric identification device according to any one of claims 1 to 5, wherein each layer of microlenses in the multilayer microlens comprises at least one microlens or a microlens array. The biometric identification device according to any one of claims 1 to 6, wherein the aperture of the microlens in the multilayer microlens is R2, and R2≤75μm. The biometric identification device according to any one of claims 1 to 7, wherein the microlens in the multilayer microlens is a polygonal microlens whose object side surface and/or the image side surface is spherical or aspherical. lens. The biometric identification device according to any one of claims 1 to 8, wherein the duty ratio of the microlenses in the multilayer microlenses is 50%-100%. The biometric identification device according to any one of claims 1 to 9, characterized in that the multilayer microlenses in the beam eye lens unit are symmetrically distributed. The biometric identification device according to any one of claims 1 to 10, wherein the object side surfaces of the microlenses in different layers in the beam eye lens unit have different surface shapes, and/or, The image side surfaces of the microlenses in different layers in the beam eye lens unit have different surface shapes. The biometric identification device according to claim 10 or 11, wherein the beam eye lens unit sequentially comprises from the object side to the image side: The first micro lens, the second micro lens and the third micro lens; Wherein, the radius of curvature of the object side surface of the first microlens is k1, the radius of curvature of the image side surface of the first microlens is k2, the radius of curvature of the object side surface of the second microlens is k3, and the The radius of curvature of the image side surface of the second microlens is k4, the radius of curvature of the object side surface of the third microlens is k5, and the radius of curvature of the image side surface of the third microlens is k6, which satisfies the following conditions: k1=- k6, k2=k5, k3=-k4. The biometric identification device according to claim 12, wherein 0.209≤k1≤0.314, k2 is infinite, and 0.066≤k3≤0.099. The biometric identification device according to any one of claims 1 to 10, wherein the multilayer microlenses in the beam eye lens unit are distributed asymmetrically. The biometric identification device according to claim 14, wherein the object side surfaces of the microlenses in different layers in the beam eye lens unit have the same surface shape, and/or, the beam eye lens unit The image-side surfaces of the microlenses in different layers have the same surface shape. The biometric identification device according to claim 14 or 15, wherein the beam eye lens unit sequentially comprises from the object side to the image side: The first micro lens, the second micro lens and the third micro lens; Wherein, the radius of curvature of the object side surface of the first microlens is k1, the radius of curvature of the image side surface of the first microlens is k2, the radius of curvature of the object side surface of the second microlens is k3, and the The radius of curvature of the image side surface of the two microlenses is k4, the radius of curvature of the object side surface of the third microlens is k5, and the radius of curvature of the image side surface of the third microlens is k6, which satisfies the following conditions: 0.104≤k1 ≤0.156, k2 is infinity, 0.077≤k3≤0.115, k4 is infinity, 0.047≤k5≤0.07, k6 is infinity. The biometric identification device according to claim 14, wherein the beam eye lens unit sequentially comprises from the object side to the image side: The first micro lens, the second micro lens and the third micro lens; Wherein, the radius of curvature of the object side surface of the first microlens is k1, the radius of curvature of the image side surface of the first microlens is k2, the radius of curvature of the object side surface of the second microlens is k3, and the The radius of curvature of the image side surface of the two microlenses is k4, the radius of curvature of the object side surface of the third microlens is k5, and the radius of curvature of the image side surface of the third microlens is k6, which satisfies the following conditions: 0.116≤k1 ≤0.174, -0.67≤k2≤-0.446, 0.068≤k3≤0.102, -0.067≤k4≤-0.045, 0.034≤k5≤0.051, k6 is infinite. The biometric identification device according to any one of claims 1 to 17, wherein the microlens included in each layer of microlenses in the multilayer microlens and the pixel unit of the image sensor satisfy a pair of One-to-many correspondence. The biometric identification device according to any one of claims 1 to 18, wherein a supporting structure is provided between the microlenses of different layers in the beam eye lens unit to support or fix the beam eye lens The microlens in the unit, the supporting structure does not affect the imaging of the beam eye lens unit on the image sensor. The biometric identification device according to any one of claims 1 to 19, wherein each layer of microlenses in the multilayer microlenses is grown on the surface of a glass substrate or a plastic substrate. The biometric identification device according to claim 20, wherein a transition layer is provided between the microlens in the multilayer microlens and the glass substrate or the plastic substrate, so that the multilayer microlens The microlenses are grown on the surface of the glass substrate or plastic substrate. The biometric identification device according to claim 20 or 21, wherein the edge area of the microlens in the multilayer microlens is covered with a light shielding layer to eliminate the influence of stray light. The biometric identification device according to claim 22, wherein the light shielding layer covers the edge area of the microlens in the multilayer microlens by more than 1.5 μm. The biometric identification device according to any one of claims 1 to 23, wherein the biometric identification device further comprises: The filter layer is arranged between the display screen and the image sensor, and is used to filter out the light signal of the non-target waveband and transmit the light signal of the target waveband. The biometric identification device according to claim 24, wherein the filter layer is grown on the surface of the image sensor, or the filter layer is disposed between the beam eye lens array and the image sensor Or, the filter layer is arranged between the display screen and the beam eye lens array. The biometric identification device according to any one of claims 1 to 25, wherein the biometric identification device further comprises: A plurality of microlens arrays, wherein each microlens array of the plurality of microlens arrays is arranged on the surface of a pixel unit of the image sensor, and part or all of the pixel unit surfaces of the image sensor are provided with the multiple A microlens array in a microlens array. The biometric identification device according to any one of claims 1 to 26, wherein the target object is at least one of a finger, a palm, and a human face. The biometric identification device according to any one of claims 1 to 27, wherein the distance between the biometric identification device and the display screen is D2, 50 μm≦D2≦1000 μm. An electronic device, characterized by comprising: a display screen and The biometric identification device according to any one of claims 1 to 27, wherein the distance between the biometric identification device and the display screen is D2, 50 μm≦D2≦1000 μm. The electronic device according to claim 29, wherein the electronic device further comprises: a low-pass filter, the low-pass filter being a low-pass filter used for image processing to eliminate the beam eye lens The influence of the unit diaphragm on the image formed by the beam eye lens unit. The electronic device according to claim 29 or 30, 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 distance between the under-screen biometric identification device and the display screen is D2.

Images