CN111108511B

CN111108511B - Fingerprint detection device and electronic equipment

Info

Publication number: CN111108511B
Application number: CN201980004247.1A
Authority: CN
Inventors: 蒋鹏; 马明; 凌伟
Original assignee: Shenzhen Goodix Technology Co Ltd
Current assignee: Shenzhen Goodix Technology Co Ltd
Priority date: 2019-07-12
Filing date: 2019-10-14
Publication date: 2023-08-22
Anticipated expiration: 2039-10-14
Also published as: CN111108511A

Abstract

The embodiment of the application relates to a fingerprint detection device and an electronic device, wherein the fingerprint detection device is applicable to the lower part of a display screen comprising a fingerprint detection area, and comprises: the fingerprint detection units are determined according to the relevant size parameters of each fingerprint detection unit or fingerprint detection area; each fingerprint detection unit comprises from top to bottom: a microlens array; at least one light blocking layer to form a plurality of inclined light guide channels corresponding to each microlens; and each optical sensing pixel is used for receiving optical signals converged by the micro lens and transmitted through the corresponding light guide channel so as to detect fingerprint information of the finger. The fingerprint detection device and the electronic equipment provided by the embodiment of the application can realize the effective identification of the field of view of the same fingerprint by using a smaller chip area, and reduce the cost.

Description

Fingerprint detection device and electronic equipment

The present application claims priority from the chinese patent office, PCT patent application No. PCT/CN2019/095880, PCT patent application No. "fingerprint detection device and electronic device" filed on 7/12, PCT patent application No. PCT/CN2019/099135, PCT patent application No. "fingerprint detection device and electronic device" filed on 8/2, and PCT patent application No. PCT/CN2019/102366, PCT patent application No. "fingerprint detection device, method and electronic device" filed on 23, 2019, 8, and the entire contents of which are incorporated herein by reference.

Technical Field

The present application relates to the field of biometric identification, and in particular, to a fingerprint detection device and an electronic device.

Background

Along with the high-speed development of the mobile phone industry, the biological recognition technology is more and more important, and the practical use of the convenient and low-cost on-screen fingerprint recognition technology is required by the masses. The under-screen optical fingerprint identification technology is to set an optical fingerprint module under a display screen, and realize fingerprint identification by collecting optical fingerprint images. With the development of end products, the requirements on fingerprint identification performance, size and cost are increasing.

For example, in some scenes, the problem of dry fingers occurs, the contact area between the dry fingers and the display screen is very small, the recognition response area is very small, the acquired fingerprints are discontinuous, the feature points are easy to lose, and the performance of fingerprint recognition is affected. In addition, the problem of how to improve the performance of fingerprint identification is solved, and meanwhile, the problems of cost, size and the like when the fingerprint identification device is applied to a special scene under a screen are also considered.

Disclosure of Invention

The application provides a fingerprint detection device and electronic equipment, which can realize effective recognition of the same fingerprint with smaller chip area, thereby reducing the chip area and the cost.

In a first aspect, a fingerprint detection device is provided, the fingerprint detection device being adapted for use in a below of a display screen to enable an under-screen optical fingerprint detection, the display screen comprising a fingerprint detection area for a finger touch for fingerprint detection, the fingerprint detection device comprising: the fingerprint detection device comprises a plurality of fingerprint detection units, wherein the size of each fingerprint detection unit and the distance between two adjacent fingerprint detection units in the plurality of fingerprint detection units are set according to size parameters, and the size parameters comprise at least one of the following parameters: the field of view scope of each fingerprint detection unit, the area of the fingerprint detection area, the thickness of the display screen and the distance from the upper surface of the light path of each fingerprint detection unit to the lower surface of the display screen.

Wherein each fingerprint detection unit comprises: a microlens array, configured to be disposed below the display screen, and including a plurality of microlenses; the light blocking layer is arranged below the micro lens array, and is provided with a plurality of light guide channels corresponding to each micro lens in the plurality of micro lenses, and an included angle between each light guide channel in the plurality of light guide channels corresponding to each micro lens and the optical axis of each micro lens is smaller than 90 degrees; the optical sensing pixel array is arranged below the at least one light blocking layer and comprises a plurality of optical sensing pixels, one optical sensing pixel is arranged below each of a plurality of light guide channels corresponding to each micro lens, and the one optical sensing pixel is used for receiving optical signals converged by the micro lenses and transmitted through the corresponding light guide channels and used for detecting fingerprint information of a finger.

Therefore, the fingerprint detection device including a plurality of fingerprint detection units according to embodiments of the present application can solve the following problems: 1. the problem that the recognition effect of the vertical light signal on the dry finger is poor; 2. the problem of overlong exposure time of a single object space telecentric microlens array scheme; 3. the problem of excessive thickness of the fingerprint detection device; 4. the tolerance of the fingerprint detection device is too bad; 5. the problem of oversized fingerprint detection device; 6. the cost of the fingerprint detection device is too high.

With reference to the first aspect, in an implementation manner of the first aspect, the plurality of fingerprint detection units are the same in size.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in another implementation manner of the first aspect, a spacing distance of a plurality of fingerprint detection units located in a same row in the plurality of fingerprint detection units is equal; and/or the spacing distances of the fingerprint detection units in the same column are equal.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in another implementation manner of the first aspect, the number of the plurality of fingerprint detection units is two.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in another implementation manner of the first aspect, two fingerprint detection units are disposed side by side.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in another implementation manner of the first aspect, the size parameter includes: and when the field of view of the upper surface of the display screen is that the edge of each fingerprint detection unit expands outwards by at least a first value X, the length of the fingerprint detection area is larger than or equal to a second value Y, and the width of the fingerprint detection area is larger than or equal to a third value Z, the length of each fingerprint detection unit is larger than or equal to Y-2X, the width of each fingerprint detection unit is larger than or equal to 0.5Z-2X, and the horizontal distance between the two fingerprint detection units is smaller than or equal to 2X.

For example, the size parameters include: and when the field of view range of the upper surface of the display screen of each fingerprint detection unit is at least 0.3mm when the edge of each fingerprint detection unit is outwards expanded, and the area of the fingerprint detection area is more than or equal to 6mm, the length of each fingerprint detection unit is more than or equal to 5.4mm, the width of each fingerprint detection unit is more than or equal to 2.4mm, and the horizontal distance between the two fingerprint detection units is less than or equal to 0.6mm.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in another implementation manner of the first aspect, a length of each fingerprint detection unit is 6mm, a width of each fingerprint detection unit is 2.3mm, and a horizontal distance between the two fingerprint detection units is 1mm.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in another implementation manner of the first aspect, a length of each fingerprint detection unit is 6.5mm, a width of each fingerprint detection unit is 2.6mm, and a horizontal distance between the two fingerprint detection units is 1mm.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in another implementation manner of the first aspect, the number of the plurality of fingerprint detection units is four.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in another implementation manner of the first aspect, the four fingerprint detection units are arranged according to a matrix of 2×2.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in another implementation manner of the first aspect, the size parameter includes: and when the field of view of the upper surface of the display screen is that the edge of each fingerprint detection unit expands outwards by at least a first value X, the length of the fingerprint detection area is larger than or equal to a second value Y, and the width of the fingerprint detection area is larger than or equal to a third value Z, the length of each fingerprint detection unit is larger than or equal to 0.5Y-2X, the width of each fingerprint detection unit is larger than or equal to 0.5Z-2X, the horizontal distance between two adjacent fingerprint detection units in the horizontal direction is smaller than or equal to 2X, and the vertical distance between two adjacent fingerprint detection units in the vertical direction is smaller than or equal to 2X.

For example, the size parameters include: under the condition that the field of view range of the upper surface of the display screen of each fingerprint detection unit is at least 0.3mm when the edge of each fingerprint detection unit is outwards expanded, and the area of the fingerprint detection area is more than or equal to 6mm, the length of each fingerprint detection unit is more than or equal to 2.4mm, the width of each fingerprint detection unit is more than or equal to 2.4mm, the horizontal distance between two adjacent fingerprint detection units in the horizontal direction is less than or equal to 0.6mm, and the vertical distance between two adjacent fingerprint detection units in the vertical direction is less than or equal to 0.6mm.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in another implementation manner of the first aspect, a length of each fingerprint detection unit is 2.3mm, a width of each fingerprint detection unit is 2.3mm, a horizontal distance between two adjacent fingerprint detection units in a horizontal direction is 1.2mm, and a vertical distance between two adjacent fingerprint detection units in a vertical direction is 1.2mm.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in another implementation manner of the first aspect, a length of each fingerprint detection unit is 2.6mm, a width of each fingerprint detection unit is 2.6mm, a horizontal distance between two adjacent fingerprint detection units in a horizontal direction is 1mm, and a vertical distance between two adjacent fingerprint detection units in a vertical direction is 1mm.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in another implementation manner of the first aspect, bottoms of the plurality of light guide channels corresponding to each microlens extend to below the adjacent plurality of microlenses respectively.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in another implementation manner of the first aspect, bottoms of the plurality of light guide channels corresponding to each microlens are located below the same microlens.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in another implementation manner of the first aspect, the plurality of light guide channels corresponding to each microlens are distributed in a central symmetry manner along an optical axis direction of the same microlens.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in another implementation manner of the first aspect, each light guide channel of the plurality of light guide channels corresponding to each microlens forms a preset included angle with a first plane, so that a plurality of optical sensing pixels disposed below each microlens are respectively used for receiving optical signals converged by one or more microlenses and transmitted through the corresponding light guide channel, where the first plane is a plane parallel to the display screen.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in another implementation manner of the first aspect, the preset included angle ranges from 15 degrees to 60 degrees.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in another implementation manner of the first aspect, projections of the plurality of light guide channels corresponding to each microlens on the first plane are symmetrically distributed with respect to a projection center of an optical axis of the same microlens on the first plane.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in another implementation manner of the first aspect, the optical sensing pixel array includes a plurality of groups of optical sensing pixels, directions of light guide channels through which light signals received by the same group of optical sensing pixels in the plurality of groups of optical sensing pixels pass are the same, the plurality of groups of optical sensing pixels are used for receiving the light signals in a plurality of directions to obtain a plurality of images, and the plurality of images are used for detecting fingerprint information of the finger.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in another implementation manner of the first aspect, a set of optical sensing pixels of the plurality of sets of optical sensing pixels is configured to receive an optical signal in one direction of the plurality of directions to obtain one image of the plurality of images.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in another implementation manner of the first aspect, the number of pixels in each group of pixels in the plurality of groups of pixels is equal, and an arrangement manner is the same.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in another implementation manner of the first aspect, one optical sensing pixel in a group of optical sensing pixels in the plurality of groups of optical sensing pixels corresponds to one pixel point in one image.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in another implementation manner of the first aspect, a plurality of consecutive optical sensing pixels in a group of optical sensing pixels in the plurality of groups of optical sensing pixels corresponds to one pixel point in one image.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in another implementation manner of the first aspect, a distribution of the plurality of optical sensing pixels under each microlens is polygonal.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in another implementation manner of the first aspect, the polygon is a rectangle or a diamond.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in another implementation manner of the first aspect, the at least one light blocking layer is a plurality of light blocking layers, and at least one opening corresponding to each microlens is disposed in a different light blocking layer, so as to form a plurality of light guide channels corresponding to each microlens.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in another implementation manner of the first aspect, the number of openings corresponding to the same microlens in different light blocking layers sequentially increases from top to bottom.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in another implementation manner of the first aspect, apertures of openings corresponding to a same microlens in different light blocking layers sequentially decrease from top to bottom.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in another implementation manner of the first aspect, a plurality of openings corresponding to each microlens are provided in a bottom light blocking layer in the plurality of light blocking layers, and a plurality of light guide channels corresponding to each microlens respectively pass through a plurality of openings corresponding to a same microlens in the bottom light blocking layer.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in another implementation manner of the first aspect, an opening is provided in a middle position of a back focal point of two adjacent microlenses in the plurality of microlenses in the non-bottom light blocking layer, and two light guide channels corresponding to the two adjacent microlenses pass through the openings corresponding to the two adjacent microlenses in the non-bottom light blocking layer, so that bottoms of the light guide channels corresponding to each microlens extend to below the adjacent microlenses respectively.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in another implementation manner of the first aspect, a top light blocking layer of the plurality of light blocking layers is provided with an opening on an optical axis of each microlens, and a plurality of light guide channels corresponding to each microlens all pass through the opening corresponding to the same microlens in the top light blocking layer.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in another implementation manner of the first aspect, the at least one light blocking layer includes only one light blocking layer, and the plurality of light guiding channels are a plurality of inclined through holes corresponding to a same microlens in the one light blocking layer.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in another implementation manner of the first aspect, a thickness of the light blocking layer is greater than a preset threshold, so that a plurality of optical sensing pixels disposed below each microlens are respectively used for receiving optical signals converged by one or more microlenses and transmitted through corresponding light guide channels.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in another implementation manner of the first aspect, each fingerprint detection unit further includes: a transparent dielectric layer disposed at least one of:

the microlens array and the at least one light blocking layer, and the at least one light blocking layer and the optically sensing pixel array.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in another implementation manner of the first aspect, the at least one light blocking layer is integrally disposed with the microlens array, or the at least one light blocking layer is integrally disposed with the optical sensing pixel array.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in another implementation manner of the first aspect, each microlens meets at least one of the following conditions: the projection of the condensing surface of the micro lens on a plane perpendicular to the optical axis of the micro lens is rectangular or circular; the condensing surface of the micro lens is an aspheric surface; the curvatures of the converging surfaces of the microlenses in all directions are the same; the microlens includes at least one lens; and the focal length range of the micro lens is 10um-2mm.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in another implementation manner of the first aspect, the microlens array meets at least one of the following conditions: the microlens array is arranged in a polygonal shape, and the duty ratio of the microlens array ranges from 100% to 50%.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in another implementation manner of the first aspect, a period of the microlens array is not equal to a period of the optical sensing pixel array, and the period of the microlens array is a rational multiple of the period of the optical sensing pixel array.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in another implementation manner of the first aspect, a distance between the fingerprint detection device and the display screen is 20um-3000um.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in another implementation manner of the first aspect, each fingerprint detection unit further includes: a filter layer disposed at least one of: above the microlens array, and between the microlens array and the optically sensitive pixel array.

In a second aspect, there is provided an electronic device comprising: a display screen; and a fingerprint detection device according to the first aspect or any possible implementation of the first aspect.

With reference to the second aspect, in an implementation manner of the second aspect, the display screen includes a fingerprint detection area, and the fingerprint detection area is used for providing a touch interface for a finger.

Drawings

Fig. 1 is a schematic front view of an electronic device of an embodiment of the application.

Fig. 2 is a schematic cross-sectional view of the electronic device of fig. 1 in accordance with an embodiment of the application.

Fig. 3 is a front view of one fingerprint detection unit in the fingerprint detection device according to an embodiment of the present application.

Fig. 4 is a front view of another fingerprint detection unit in the fingerprint detection device according to an embodiment of the present application.

Fig. 5 is a schematic top view of any microlens and its corresponding optical sensing pixel in the fingerprint detection unit according to an embodiment of the present application.

Fig. 6 is another schematic top view of any microlens and its corresponding optically sensitive pixel in the fingerprint detection unit of an embodiment of the present application.

Fig. 7 is a front view of another fingerprint detection unit in the fingerprint detection device according to an embodiment of the present application.

Fig. 8 is a front view of another fingerprint detection unit in the fingerprint detection device according to an embodiment of the present application.

Fig. 9 is a schematic view of fields of view of a fingerprint detection device having a single fingerprint detection unit according to an embodiment of the present application.

Fig. 10 is a schematic diagram of a calculation mode of a field of view of a fingerprint detection device having a single fingerprint detection unit according to an embodiment of the present application.

Fig. 11 is a schematic view of fields of view of a fingerprint detection device having a plurality of fingerprint detection units according to an embodiment of the present application.

Fig. 12 is a schematic front view of an arrangement of two fingerprint detection units according to an embodiment of the present application.

Fig. 13 is a schematic front view of an arrangement of four fingerprint detection units according to an embodiment of the present application.

Fig. 14 is a schematic side view of an arrangement of four fingerprint detection units 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.

The technical scheme of the embodiment of the application can be applied to various electronic equipment. For example, smart phones, notebook computers, tablet computers, gaming devices, and other portable or mobile computing devices, as well as electronic databases, automobiles, bank automated teller machines (Automated Teller Machine, ATM), and other electronic devices. However, the embodiment of the present application is not limited thereto.

The technical scheme of the embodiment of the application can be used for the biological characteristic recognition technology. The biometric technology includes, but is not limited to, fingerprint recognition, palm print recognition, iris recognition, face recognition, living body recognition, and the like. For ease of explanation, fingerprint recognition techniques are described below as examples.

The technical scheme of the embodiment of the application can be used for the under-screen fingerprint identification technology and the in-screen fingerprint identification technology.

The under-screen fingerprint identification technology is characterized in that the fingerprint identification module is arranged below the display screen, so that fingerprint identification operation is carried out in the display area of the display screen, and a fingerprint acquisition area is not required to be arranged in an area except the display area on the front side of the electronic equipment. Specifically, the fingerprint recognition module uses light returned from the top surface of the display assembly of the electronic device for fingerprint sensing and other sensing operations. This returned light carries information about an object (e.g., a finger) in contact with or in proximity to the top surface of the display assembly, and the fingerprint recognition module located below the display assembly performs off-screen fingerprint recognition by capturing and detecting this returned light. The fingerprint recognition module can be designed to realize expected optical imaging by properly configuring optical elements for collecting and detecting returned light, so as to detect fingerprint information of a finger.

Correspondingly, the In-screen (In-display) fingerprint identification technology refers to that a fingerprint identification module or a part of fingerprint identification modules are arranged inside a display screen, so that fingerprint identification operation is carried out In a display area of the display screen, and a fingerprint acquisition area is not required to be arranged In an area except the display area on the front side of the electronic equipment.

Fig. 1 to 2 show schematic diagrams of electronic devices to which embodiments of the present application may be applied. Fig. 1 is a front view of an electronic device 10, and fig. 2 is a schematic cross-sectional view of the electronic device 10 shown in fig. 1.

As shown in fig. 1 and 2, the electronic device 10 may include a display 120 and an optical fingerprint recognition module 130.

The display screen 120 may be a self-luminous display screen employing a display unit having self-luminescence as display pixels. For example, the display 120 may be an Organic Light-Emitting Diode (OLED) display or a Micro-LED (Micro-LED) display. In other alternative embodiments, the display 120 may be a liquid crystal display (Liquid Crystal Display, LCD) or other passive light emitting display, which is not limited in this regard. Further, the display screen 120 may be specifically a touch display screen, which not only can perform screen display, but also can detect touch or press operation of a user, so as to provide a personal computer interaction interface for the user. For example, in one embodiment, the electronic device 10 may include a Touch sensor, which may be embodied as a Touch Panel (TP), which may be disposed on a surface of the display 120, or may be partially integrated or entirely integrated within the display 120, thereby forming a Touch display.

The optical fingerprint module 130 includes an optical fingerprint sensor including a sensing array 133 having a plurality of optical sensing units 131 (which may also be referred to as optical sensing pixels, photosensitive pixels, pixel units, etc.). The sensing area of the sensing array 133 or the sensing area thereof is a fingerprint detection area 103 (also referred to as a fingerprint acquisition area, a fingerprint identification area, etc.) corresponding to the optical fingerprint module 130.

The optical fingerprint module 130 is disposed in a local area under the display screen 120.

As shown in fig. 1, the fingerprint detection area 103 may be located within the display area of the display screen 120. In an alternative embodiment, the optical fingerprint module 130 may be disposed at other locations, such as the side of the display screen 120 or an edge non-transparent area of the electronic device 10, and the optical signals from at least a portion of the display area of the display screen 120 are directed to the optical fingerprint module 130 by an optical path design such that the fingerprint detection area 103 is actually located in the display area of the display screen 120.

For the electronic device 10, when the user needs to unlock the electronic device 10 or perform other fingerprint verification, the user only needs to press the finger on the fingerprint detection area 103 located on the display screen 120, so that fingerprint input can be realized. Since fingerprint detection can be implemented in the screen, the electronic device 10 adopting the above structure does not need to have a special reserved space on the front surface to set fingerprint keys (such as Home keys), so that a full-screen scheme can be adopted, that is, the display area of the display screen 120 can be basically expanded to the front surface of the whole electronic device 10.

As shown in fig. 2, the optical fingerprint module 130 may include a light detecting portion 134 and an optical component 132. The light detecting section 134 includes a sensing array 133 (which may also be referred to as an optical fingerprint sensor) and a reading circuit and other auxiliary circuits electrically connected to the sensing array 133, which may be fabricated on a chip (Die) such as an optical imaging chip or an optical fingerprint sensor by a semiconductor process. The sensor array 133 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 sensor units described above. The optical assembly 132 may be disposed above the sensor array 133 of the light detecting portion 134, and may specifically include a Filter layer (Filter) that may be used to Filter out ambient light that penetrates the finger, a light guiding layer or light path guiding structure that is mainly used to guide reflected light reflected from the finger surface to the sensor array 133 for optical detection, and other optical elements.

In some embodiments of the present application, the optical assembly 132 may be packaged in the same optical fingerprint component as the light detection section 134. For example, the optical component 132 may be packaged in the same optical fingerprint chip as the optical detecting portion 134, or the optical component 132 may be disposed outside the chip in which the optical detecting portion 134 is located, for example, the optical component 132 is attached to the chip, or part of the components of the optical component 132 are integrated in the chip.

In some embodiments of the present application, the area or the photo-sensing range of the sensing array 133 of the optical fingerprint module 130 corresponds to the fingerprint detection area 103 of the optical fingerprint module 130. The fingerprint collection area 103 of the optical fingerprint module 130 may be equal to or different from the area or the light sensing range of the area where the sensing array 133 of the optical fingerprint module 130 is located, which is not limited in the embodiment of the present application.

For example, the fingerprint detection area 103 of the optical fingerprint module 130 may be designed to be substantially identical to the area of the sensing array of the optical fingerprint module 130 by performing light path guidance through light collimation.

For another example, the area of the fingerprint detection area 103 of the optical fingerprint module 130 may be larger than the area of the sensing array 133 of the optical fingerprint module 130, for example, by a light path design such as lens imaging, a reflective folded light path design, or other light path designs such as light converging or reflecting.

The following exemplifies the light path guiding structure that the optical assembly 132 may include.

Taking the optical path guiding structure as an example, the optical Collimator comprises a through hole array with a high aspect ratio, the optical Collimator can be specifically a Collimator (Collimator) layer manufactured on a semiconductor silicon wafer, the optical Collimator is provided with a plurality of collimating units or micropores, the collimating units can be specifically small holes, the light vertically incident to the collimating units can pass through and be received by the sensor chips below the collimating units in the reflected light reflected by fingers, and the light with an excessive incident angle is attenuated in the collimating units through multiple reflections, so that each sensor chip basically only can receive the reflected light reflected by the fingerprint lines right above the sensor chips, the image resolution can be effectively improved, and the fingerprint identification effect is further improved.

Taking an optical path design in which the optical path guiding structure includes an optical Lens as an example, the optical path guiding structure may be an optical Lens (Lens) layer having one or more Lens units, such as a Lens group composed of one or more aspherical lenses, for converging reflected light reflected from a finger to a sensing array 133 of a light detecting portion 134 thereunder so that the sensing array 133 may image based on the reflected light, thereby obtaining a fingerprint image of the finger. Further, the optical lens layer may further be formed with a pinhole or a micropore diaphragm in the optical path of the lens unit, for example, one or more light shielding sheets may be formed in the optical path of the lens unit, wherein at least one light shielding sheet may be formed with a light transmitting micropore as the pinhole or micropore diaphragm in the optical axis or optical center area of the lens unit. The pinhole or microporous diaphragm can be matched with the optical lens layer and/or other optical film layers above the optical lens layer to expand the field of view of the optical fingerprint module 130 so as to improve the fingerprint imaging effect of the optical fingerprint module 130.

Taking an example of an optical path design in which the optical path guiding structure includes a Micro-Lens layer, the optical path guiding structure may be a Micro-Lens array including a plurality of Micro-lenses, which may be formed over the sensing array 133 of the light sensing part 134 by a semiconductor growth process or other processes, and each Micro-Lens may correspond to one of sensing cells of the sensing array 133, respectively. And other optical film layers, such as a dielectric layer or a passivation layer, can be formed between the microlens layer and the sensing unit. More specifically, a light blocking layer (or referred to as a light blocking layer, etc.) having micro holes (or referred to as openings) may be further included between the micro lens layer and the sensing unit, wherein the micro holes are formed between the micro lenses corresponding thereto, the light blocking layer may block optical interference between adjacent micro lenses and the sensing unit, and cause light corresponding to the sensing unit to be condensed into the micro holes through the micro lenses and transmitted to the sensing unit through the micro holes for optical fingerprint imaging.

It should be appreciated that several of the implementations described above for the light path guiding structure may be used alone or in combination with one another.

For example, a microlens layer may be further provided above or 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 laminated structure or the optical path thereof may need to be adjusted as actually needed.

On the other hand, the optical component 132 may further include other optical elements, such as a Filter layer (Filter) or other optical film, which may be disposed between the optical path guiding structure and the optical fingerprint sensor or between the display screen 120 and the optical path guiding structure, mainly for isolating the influence of the external disturbance light on the optical fingerprint detection. The filter layer may be used to filter out ambient light that penetrates through the finger and enters the optical fingerprint sensor through the display 120, similar to the light path guiding structure, and the filter layer may be separately disposed for each optical fingerprint sensor to filter out interference light, or may also use a large-area filter layer to cover the plurality of optical fingerprint sensors simultaneously.

The fingerprint recognition module 140 may be configured to collect fingerprint information (such as fingerprint image information) of a user.

Taking the display screen 120 as an example, a display screen having a self-luminous display unit, such as an Organic Light-Emitting Diode (OLED) display screen or a Micro-Light-Emitting Diode (Micro-LED) display screen, is adopted. The optical fingerprint module 130 can use the display unit (i.e., OLED light source) of the OLED display 120 located in the fingerprint detection area 103 as an excitation light source for optical fingerprint detection. When the finger 140 is pressed against the fingerprint detection area 103, the display 120 emits a beam of light 111 towards the target finger 140 above the fingerprint detection area 103, which light 111 is reflected at the surface of the finger 140 to form reflected light or scattered inside the finger 140 to form scattered light (transmitted light).

In the embodiment of the present application, for convenience of description, the above reflected light and scattered light are collectively referred to as return light. Since the ridge (ridge) 141 and the valley (valley) 142 of the fingerprint have different light reflection capacities, the reflected light 151 from the ridge and the reflected light 152 from the valley have different light intensities, and the reflected light is received by the sensing array 133 in the optical fingerprint module 130 and converted into corresponding electrical signals, i.e. fingerprint detection signals after passing through the optical component 132; fingerprint image data can be obtained based on the fingerprint detection signal, and fingerprint matching verification can be further performed, thereby realizing an optical fingerprint recognition function in the electronic device 10.

In other alternatives, the optical fingerprint module 130 may also use an internal light source or an external light source to provide an optical signal for fingerprint detection and identification. In this case, the optical fingerprint module 130 may be applied to not only a self-luminous display screen such as an OLED display screen, but also a non-self-luminous display screen such as a liquid crystal display screen or other passive light-emitting display screen.

For a liquid crystal display having a backlight module and a liquid crystal panel, to support under-screen fingerprint detection of the liquid crystal display, the optical fingerprint system of the electronic device 10 may further include an excitation light source for optical fingerprint detection, which may be specifically an infrared light source or a light source of non-visible light with a specific wavelength, which may be disposed under the backlight module of the liquid crystal display or an edge region under a protective cover plate of the electronic device 10, and the optical fingerprint module 130 may be disposed under the edge region of the liquid crystal panel or the protective cover plate and guided through an optical path so that fingerprint detection light may reach the optical fingerprint module 130; alternatively, the optical fingerprint module 130 may be disposed below the backlight module, and the backlight module may be provided with holes or other optical designs to allow the fingerprint detection light to pass through the liquid crystal panel and the backlight module and reach the optical fingerprint module 130 by making holes on a film layer such as a diffusion sheet, a brightness enhancement sheet, a reflection sheet, etc. When the optical fingerprint module 130 is used to provide an optical signal for fingerprint detection using an internal light source or an external light source, the detection principle is consistent with that described above.

In particular implementations, the electronic device 10 may also include a transparent protective cover plate, which may be a glass cover plate or a sapphire cover plate, that is positioned over the display screen 120 and covers the front of the electronic device 10. Thus, in embodiments of the present application, the pressing of a finger against the display 120 actually refers to pressing a cover plate over the display 120 or a protective layer surface covering the cover plate.

On the other hand, the optical fingerprint module 130 may only include one optical fingerprint sensor, and at this time, the area of the fingerprint detection area 103 of the optical fingerprint module 130 is smaller and the position is fixed, so that the user needs to press the finger to a specific position of the fingerprint detection area 103 when inputting the fingerprint, otherwise, the optical fingerprint module 130 may not be able to collect the fingerprint image, resulting in poor user experience. In other alternative embodiments, the optical fingerprint module 130 may specifically include a plurality of optical fingerprint sensors. The optical fingerprint sensors can be arranged side by side below the display screen 120 in a splicing manner, and the sensing areas of the optical fingerprint sensors together form the fingerprint detection area 103 of the optical fingerprint module 130. The fingerprint detection area 103 of the optical fingerprint module 130 can be extended to the main area of the lower half of the display screen, i.e. to the usual finger pressing area, so as to realize blind press type fingerprint input operation. Further, when the number of the optical fingerprint sensors is sufficient, the fingerprint detection area 103 may also be extended to half the display area or even the whole display area, thereby realizing half-screen or full-screen fingerprint detection.

With the development of terminal products, requirements on the performance of off-screen fingerprint identification are higher and higher. However, in some scenes, there may be a problem of a dry finger, the contact area between the dry finger and the display screen is very small, the recognition response area is very small, the acquired fingerprint is discontinuous, the feature points are easy to lose, and the performance of fingerprint recognition is affected. Therefore, the embodiment of the application provides a fingerprint detection device, which can solve the problem that the fingerprint identification effect of the existing fingerprint identification scheme on dry fingers is poor, namely the fingerprint identification performance on the dry fingers can be improved.

Specifically, the fingerprint detection device of the embodiment of the application is suitable for being used below a display screen to realize the optical fingerprint detection under the screen. The fingerprint detection device in the embodiment of the application comprises a plurality of fingerprint detection units. Any one of the plurality of fingerprint detection units will be described in detail below with reference to fig. 3 to 8.

Specifically, fig. 3 and 4 each show a schematic diagram of the fingerprint detection unit 20 according to an embodiment of the present application. The fingerprint detection unit 20 may be adapted to the electronic device 10 shown in fig. 1-2, or the fingerprint detection unit 20 may be an optical fingerprint module 130 shown in fig. 1-2.

As shown in fig. 3 and 4, the fingerprint detection unit 20 may include a microlens array 210, at least one light blocking layer, and an optical sensing pixel array 240. The microlens array 210 may be adapted to be disposed under a display screen of an electronic device, the at least one light blocking layer may be disposed under the microlens array 210, and the optical sensing pixel array 240 may be disposed under the at least one light blocking layer.

It should be understood that the microlens array 210 and the at least one light blocking layer may be light guiding structures included in the optical assembly 132 shown in fig. 2, and the optical sensing pixel array 240 may be the sensing array 133 having a plurality of optical sensing units 131 (may also be referred to as optical sensing pixels, photosensitive pixels, pixel units, etc.) shown in fig. 1 to 2, and for brevity, will not be repeated herein.

In an embodiment of the present application, the microlens array 210 may include a plurality of microlenses. For example, as shown in fig. 3 and 4, the microlens array 210 may include a first microlens 211, a second microlens 212, and a third microlens 213. The at least one light blocking layer may include a plurality of light blocking layers, for example, as shown in fig. 3 and 4, the at least one light blocking layer may include a first light blocking layer 220 and a second light blocking layer 230. The photo-sensing pixel array 240 may include a plurality of photo-sensing pixels, for example, as shown in fig. 3 and 4, the photo-sensing pixel array 240 may include a first photo-sensing pixel 241, a second photo-sensing pixel 242, a third photo-sensing pixel 243, a fourth photo-sensing pixel 244, a fifth photo-sensing pixel 245, and a sixth photo-sensing pixel 246.

Alternatively, each microlens in the microlens array 210 may be filled in a circular shape or may be filled in a square shape; in addition, the material of each microlens in the microlens array 210 can be plastic or glass; each microlens production process in the microlens array 210 can be implemented through a micro-nano machining process or a press molding process, and embodiments of the present application are not limited thereto.

In the embodiment of the present application, the at least one light blocking layer and the microlens array 210 may be integrally disposed, or the at least one light blocking layer and the optical sensing pixel array 240 may be integrally disposed, even though the microlens array 210, the at least one light blocking layer and the optical sensing pixel array 240 are integrally disposed as one component, the embodiment of the present application is not limited thereto.

Alternatively, each microlens in the microlens array 210 can satisfy at least one of the following conditions: the projection of the condensing surface of the micro lens on a plane perpendicular to the optical axis is rectangular or circular; the condensing surface of the micro lens is a sphere or an aspheric surface; the curvatures of the converging surfaces of the microlenses in all directions are the same; the microlens includes at least one lens; and the focal length of the micro lens is in the range of 10um-2mm.

In an embodiment of the present application, the microlens array 210 satisfies at least one of the following conditions: the microlens array 210 is arranged in a polygonal shape and the duty cycle of the microlens array 210 ranges from 100% to 50%. For example, the microlens array 210 is arranged in a square or hexagonal shape. For another example, the duty cycle of the microlens array 210 is 85%.

In the embodiment of the present application, the period of the microlens array 210 is not equal to the period of the optical sensing pixel array 240, and the period of the microlens array 210 is a rational multiple of the period of the optical sensing pixel array 240, so as to avoid moire fringes in the fingerprint imaging process and improve fingerprint identification effect.

In the embodiment of the present application, the distance between the fingerprint detection unit 20 and the display screen may be set to 20um-1000um according to practical applications, so as to ensure that the fingerprint detection unit 20 and the display screen have a sufficient safety distance, and further ensure that the fingerprint detection unit 20 cannot impact the display screen to cause damage to devices due to vibration or falling of the electronic device.

It should be understood that at least one light blocking layer of the embodiment of the present application is formed with a plurality of light guiding channels corresponding to each microlens in the microlens array 210, and an included angle between each light guiding channel of the plurality of light guiding channels corresponding to each microlens and an optical axis of the corresponding microlens is smaller than 90 °, that is, for any one microlens, the plurality of light guiding channels corresponding to the microlens is inclined instead of vertical.

It should be noted that the included angle may be an included angle between the central axis of the light guide channel and the optical axis of the micro lens, or an included angle between any straight line passing through the light guide channel and the optical axis; in addition, the included angle may be any range from 0 ° to 90 °, for example, the included angle may be from 15 ° to 60 °, or from 10 ° to 70 °, for example, the included angle may be equal to 20 °, or may be equal to 40 °, but the embodiment of the present application is not limited thereto.

It should be understood that, the included angle between the light guiding channel and the optical axis of the corresponding microlens may be set to any value different from 90 ° according to practical applications, for example, the included angle between the light guiding channel and the optical axis of the corresponding microlens may be adjusted by appropriately adjusting the distances among the microlens array 210, the at least one light blocking layer, and the optical sensing pixel array 240. Since the included angle between the light guide channels and the optical axes of the corresponding microlenses is not equal to 90 °, the bottommost portions of the light guide channels of the same microlens may be located below the same microlens or may be located below different microlenses.

Alternatively, for any one microlens, the bottom of the corresponding plurality of light guide channels of the microlens may still be located below the microlens, for example, as shown in fig. 4.

Alternatively, for any one microlens, the bottoms of the light guide channels corresponding to the microlens may be located not below the microlens but below other different microlenses. For example, the bottoms of the light guide channels corresponding to the same microlens may extend below the adjacent microlenses, for example, as shown in fig. 3; alternatively, the bottoms of the light guide channels corresponding to the same microlens may also extend below the other microlenses that are not adjacent to the microlens, which is not limited by the embodiment of the present application.

It should be understood that, for convenience of explanation, in the following, in connection with fig. 3, an example will be taken that the bottoms of the light guide channels corresponding to each microlens extend below the adjacent microlenses, and in connection with fig. 4, in which the bottoms of the light guide channels corresponding to each microlens are still located below the microlenses, for other cases, the light guide channels and the optical axes of the corresponding microlenses may be adjusted by adjusting the distance between the microlens array 210, the at least one light blocking layer, and the optical sensing pixel array 240, or by adjusting the included angle between the light guide channels and the optical axes of the corresponding microlenses, which will not be described herein for brevity.

Specifically, as shown in fig. 3, at least one opening is provided in each of the first light blocking layer 220 and the second light blocking layer 230 so as to form a plurality of light guide channels corresponding to each of the plurality of microlenses (i.e., the first microlens 211, the second microlens 212, and the third microlens 213). Specifically, for convenience of description, a description will be given here by taking, as an example, a hole included in an area range that can be covered by each microlens at a position below, hereinafter, simply referred to as a coverage of the microlens. For example, in fig. 3, the first light blocking layer 220 is provided with first and second openings 221 and 222 within the coverage of the first microlenses 211; the first light blocking layer 220 is further provided with second and third openings 222 and 223 within the coverage of the second microlenses 212; the first light blocking layer 220 is further provided with third openings 223 and fourth openings 224 within the coverage of the third microlenses 213; for another example, in fig. 4, there is a similar arrangement, and the specific arrangement is shown in fig. 4, and is not described herein.

Similarly, as shown in fig. 3, the second light blocking layer 230 is provided with fifth and sixth openings 231 and 232 within the coverage of the first microlenses 211; the second light blocking layer 230 is further provided with seventh and eighth openings 233 and 234 within the coverage of the second microlenses 212; the second light blocking layer 230 is further provided with ninth and tenth openings 235 and 236 within a coverage area of the third microlenses 213. Similarly, fig. 4 shows a similar arrangement, and the specific arrangement is shown in fig. 4, which is not repeated here.

For convenience of explanation, the second microlens 212 will be mainly described as an example, but the description thereof is equally applicable to the first microlens 211 and the third microlens 213. Specifically, as shown in fig. 3, the plurality of light guide channels corresponding to the second microlenses 212 may include light guide channels formed by the second apertures 222 and the sixth apertures 232, and light guide channels formed by the third apertures 223 and the ninth apertures 235. In addition, the light guide channel formed by the second aperture 222 and the sixth aperture 232 extends below the first microlens 211, and the light guide channel formed by the third aperture 223 and the ninth aperture 235 extends below the third microlens 213. As shown in fig. 4, the plurality of light guide channels corresponding to the second microlenses 212 may include: light guiding channels formed by aperture 226 and aperture 233, light guiding channels formed by aperture 226 and aperture 234, light guiding channels formed by aperture 227 and aperture 233, and light guiding channels formed by aperture 227 and aperture 234. In addition, the four light guide channels extend below the second micro lenses 211.

It should be understood that, in the embodiment of the present application, the hole corresponding to any one of the microlenses refers to a plurality of holes through which the corresponding light guide channel passes, for example, the hole corresponding to the second microlens 212 refers to a plurality of holes through which the light guide channel passes, for example, the hole corresponding to the second microlens 212 in fig. 3 may include the holes through which the two light guide channels pass, that is, the hole corresponding to the second microlens 212 includes at least the second opening 222, the sixth opening 232, the third opening 223, and the ninth opening 235; as another example, the holes corresponding to the second microlenses 212 in fig. 4 can include the holes of the four light guide channels described above, namely, the holes 226, 227, 233, and 234.

Further, an optical sensing pixel may be disposed under each of the plurality of light guiding channels corresponding to each microlens in the microlens array 210.

Still taking the second microlens 212 of fig. 3 as an example, a second photo-sensing pixel 242 is disposed under the light guiding channel formed by the second opening 222 and the sixth opening 232, and a fifth photo-sensing pixel 245 is disposed under the light guiding channel formed by the third opening 223 and the ninth opening 235. With respect to the second microlens 221 in fig. 4, a third photo-sensing pixel 243 is disposed below the light guide channel formed by the aperture 226 and the aperture 233 and the light guide channel formed by the aperture 227 and the aperture 233; a fourth photo-sensing pixel 244 is disposed below the light guide channel formed by aperture 226 and aperture 234 and the light guide channel formed by aperture 227 and aperture 234.

Further, a plurality of optical sensing pixels are disposed under each microlens in the microlens array 210, and the plurality of optical sensing pixels disposed under each microlens are respectively configured to receive optical signals converged by one or more microlenses and transmitted through the corresponding light guide channel, and the optical signals are configured to detect fingerprint information of a finger. That is, for any one microlens, if bottoms of the light guide channels corresponding to the microlens are still located below the microlens, the optical sensing pixels disposed below the microlens are respectively used for receiving the optical signals converged by the microlens and transmitted through the light guide channels corresponding to the microlens; or if bottoms of the light guide channels corresponding to the microlenses extend to the lower parts of the adjacent microlenses, the optical sensing pixels arranged below the microlenses are respectively used for receiving the optical signals converged by the adjacent microlenses and transmitted through the corresponding light guide channels.

Still taking the second microlens 212 of fig. 3 as an example, two optical sensing pixels are disposed within a range directly under the coverage of the second microlens 212 of fig. 3, that is, a third optical sensing pixel 243 and a fourth optical sensing pixel 244 may be disposed under the second microlens 212, wherein the third optical sensing pixel 243 may be used to receive oblique light signals converged by the first microlens 211 and transmitted through the light guide channel formed by the second aperture 222 and the seventh aperture 233, and the fourth optical sensing pixel 244 may be used to receive oblique light signals converged by the third microlens 213 and transmitted through the light guide channel formed by the third aperture 223 and the eighth aperture 234, and the first microlens 211 and the third microlens 213 are adjacent to the second microlens 212.

As another example, as shown in fig. 4, taking the second microlens 212 as an example, two optical sensing pixels are disposed within a range right below the second microlens 212, that is, a third optical sensing pixel 243 and a fourth optical sensing pixel 244 may be disposed below the second microlens 212, wherein the third optical sensing pixel 243 may be used to receive the oblique optical signal converged by the second microlens 212 and transmitted through the light guide channel formed by the aperture 226 and the aperture 233, and the third optical sensing pixel 243 may be used to receive the oblique optical signal converged by the second microlens 212 and transmitted through the light guide channel formed by the aperture 227 and the aperture 233; similarly, the fourth photo-sensing pixel 244 can be used to receive oblique light signals that are converged by the second microlens 212 and transmitted through the light guide channel formed by the aperture 226 and the aperture 234, and the fourth photo-sensing pixel 244 can also be used to receive oblique light signals that are converged by the second microlens 212 and transmitted through the light guide channel formed by the aperture 227 and the aperture 234.

In addition, the number of the plurality of optical sensing pixels under each microlens in the microlens array 210 may be set according to practical applications, for example, in the embodiment of the present application, 4 optical sensing pixels are set under each microlens as an example; alternatively, 9 optical sensing pixels may be disposed below each microlens, or other numbers may be disposed below each microlens, which is not limited by the embodiment of the present application. In addition, the distribution of the plurality of photo-sensing pixels under each microlens may be polygonal. For example, the polygon includes, but is not limited to, a rectangle or a diamond. For another example, the distribution of the plurality of optically sensitive pixels under each microlens in the microlens array 210 can be circular or elliptical.

Because the micro lenses in the micro lens array are distributed in an array mode, when the distribution of a plurality of optical sensing pixels below each micro lens is polygonal, the corresponding modes of the micro lens array and the optical sensing array can be effectively simplified, and the structural design of the fingerprint detection unit is further simplified. Specifically, fig. 5 and 6 are two schematic top views of the second microlenses 212 shown in fig. 3 or 4, respectively. As shown in fig. 5 and 6, it is assumed here that 4 photo-sensing pixels may be disposed under the second microlens 212, wherein the distribution of 4 photo-sensing pixels in fig. 5 may be represented as a rectangle, and the distribution of 4 microlenses in fig. 6 may be represented as a diamond.

It should be noted that, the specific corresponding manner of each microlens and the optical sensing pixel below the microlens is not limited in the embodiment of the present application. Taking the third photo-sensing pixel 243 below the second micro-lens 212 as an example, the second micro-lens 212 may cover a part or all of the photosensitive area (AA) of the third photo-sensing pixel 243. Preferably, taking the light guide channel of fig. 3 as an example, the second micro lens 212 may cover an area, which can be irradiated by the oblique light signal collected by the first micro lens 211 and transmitted through the light guide channel formed by the second opening 222 and the seventh opening 233, in the photosensitive area (PD area, AA) of the third optical sensing pixel 243, for example, a diagonally shaded area in each of the photosensitive areas in fig. 5 and 6, so as to ensure that the third optical sensing pixel 243 can receive enough light signals to enhance the fingerprint recognition effect.

The design of the light guide channels corresponding to each microlens is described in detail below.

In some embodiments of the present application, the plurality of light guide channels corresponding to each microlens in the microlens array 210 may be distributed centrally and symmetrically along the optical axis direction of the same microlens. The plurality of light guide channels corresponding to each microlens are arranged in a central symmetry mode, so that the process complexity of the fingerprint detection unit can be reduced, namely the process complexity of the whole fingerprint detection device can be reduced.

Taking the second microlens 212 in fig. 3 as an example, as shown in fig. 5, the light guide channel that can extend below the upper right-hand microlens and the light guide channel that can extend below the lower left-hand microlens are symmetrical with each other along the optical axis direction of the second microlens 212; among the plurality of light guide channels of the second microlens 212, a light guide channel that can extend below the upper left-hand corner microlens and a light guide channel that can extend below the lower right-hand corner microlens are also center-symmetrical in the optical axis direction of the second microlens 212. The light guide channels in fig. 4 are also similar and are not described in detail herein for brevity.

In some embodiments of the present application, each of the plurality of light guide channels corresponding to each microlens in the microlens array 210 and the first plane may form a preset included angle, so that a plurality of optical sensing pixels disposed below each microlens are respectively used for receiving optical signals converged by one or more microlenses and transmitted through the corresponding light guide channel, where the first plane is a plane parallel to the display screen. The bottom ends of the light guide channels corresponding to each microlens can be ensured to extend to the lower part of the same microlens or to the lower parts of the adjacent microlenses through the preset included angle.

As shown in fig. 3 and 5, taking the second microlens 212 as an example, the plane of the optical sensing pixel array 240 is parallel to the first plane, the light guiding channel formed by the second opening 222 and the sixth opening 232 forms a first angle with the plane of the optical sensing pixel array 240, and the light guiding channel formed by the third opening 223 and the ninth opening 235 forms a second angle with the plane of the optical sensing pixel array 240. Wherein the first angle is equal to the second angle. Of course, in other alternative embodiments, the first angle may not be equal to the second angle, which is not limited by the embodiments of the present application. And the light guide channels in fig. 4 are also similar, and are not described here again for brevity.

It should be noted that, the preset included angle may be an included angle between the central axis of the light guide channel and the first plane, or an included angle between any straight line passing through the light guide channel and the first plane; in addition, the preset included angle may be any range from 0 to 90 degrees, for example, the preset included angle may be from 15 to 60 degrees, or from 10 to 70 degrees, which is not limited in the present application.

In some embodiments of the present application, the projections of the plurality of light guide channels corresponding to each microlens in the microlens array 210 on the first plane may be distributed centrosymmetrically with respect to the projections of the optical axes of the same microlens on the first plane, so as to ensure that each optical sensing pixel in the optical sensing pixel array 240 can receive enough optical signals, thereby improving the resolution of the fingerprint image and the fingerprint identification effect.

As shown in fig. 3 and fig. 5, taking the second micro-lens 212 as an example, since each light guiding channel is an inclined channel, the end face of each light guiding channel on the first plane is elliptical, and the 4 light guiding channels corresponding to the second micro-lens 212 are symmetrically distributed along the projection center of the optical axis of the second micro-lens 212 on the first plane at the end face near the optical sensing pixel array 240.

The implementation of at least one light blocking layer in the fingerprint detection unit 20 is described in detail below.

In some embodiments of the present application, the fingerprint detection unit 20 may include a plurality of light blocking layers, at least one opening corresponding to each microlens being provided in a different light blocking layer to form a plurality of light guiding channels corresponding to the microlens. For example, the at least one light blocking layer may include the first light blocking layer 220 and the second light blocking layer 230 described above with respect to fig. 3 or 4. As another example, the fingerprint detection unit 20 may include further light blocking layers in addition to the two light blocking layers described in fig. 3 and 4, as illustrated in fig. 3, and correspondingly fig. 7 is another schematic structural diagram of the fingerprint detection unit 20 according to an embodiment of the present application. As shown in fig. 7, the fingerprint detection unit 20 may include a third light blocking layer 260 in addition to the first light blocking layer 220 and the second light blocking layer 230 shown in fig. 3, wherein the third light blocking layer 260 includes an eleventh aperture 261, a twelfth aperture 262, and a thirteenth aperture 263. For convenience of explanation, the following description will be mainly given by way of example of fig. 3 and 7.

In some implementations, the number of apertures in different light blocking layers corresponding to the same microlens may be the same, for example as shown in fig. 4; or the number of the openings corresponding to the same micro lens in different light blocking layers can be sequentially increased or decreased from top to bottom so as to form a plurality of light guide channels corresponding to each micro lens.

Taking an example that the number of openings corresponding to the same microlens in different light blocking layers may be sequentially increased from top to bottom, in other words, the pitch between the openings in different light blocking layers may be sequentially decreased from top to bottom. For example, as shown in fig. 3, a distance D between adjacent two openings in the first light blocking layer 220 is larger than a distance D between adjacent two openings in the second light blocking layer 230. The light signal which is not expected to be received by most fingerprint detection units is shielded by the upper light blocking layer with smaller aperture density in the plurality of light blocking layers, and a plurality of light guide channels corresponding to each microlens can be formed by the upper light blocking layer with smaller aperture density and the lower light blocking layer with larger aperture density in the plurality of light blocking layers. In addition, it is also possible to reduce the manufacturing complexity of the at least one light blocking layer and increase the strength of the upper light blocking layer.

In the embodiment of the application, the bottom light blocking layer of the plurality of light blocking layers can be provided with a plurality of openings corresponding to each microlens, and a plurality of light guide channels corresponding to each microlens respectively pass through the plurality of openings corresponding to the same microlens in the bottom light blocking layer. For example, as shown in fig. 3 and fig. 7, taking the second microlens 212 as an example, a sixth opening 232 and a ninth opening 235 corresponding to the second microlens 212 are disposed on the second light blocking layer 230, and two light guiding channels of the plurality of light guiding channels of the second microlens 212 respectively pass through the sixth opening 232 and the ninth opening 235.

In the embodiment of the application, the top light blocking layer of the plurality of light blocking layers can be provided with an opening on the optical axis of each microlens, and the plurality of light guide channels corresponding to the microlenses pass through the opening corresponding to the microlenses in the top light blocking layer. For example, as shown in fig. 7, with respect to the second microlens 212, the third light blocking layer 260 may be provided with a twelfth aperture 262 at a position close to the first light blocking layer 220 in the optical axis direction of the second microlens 260. At this time, one light guiding channel corresponding to the second micro lens 212 passes through the twelfth opening 262, the second opening 222 and the sixth opening 232, and the other light guiding channel corresponding to the second micro lens 212 passes through the twelfth opening 262, the third opening 223 and the ninth opening 235, i.e. both light guiding channels of the second micro lens 212 pass through the twelfth opening 262.

In the embodiment of the present application, in a case where bottoms of a plurality of light guide channels corresponding to the same microlens extend below an adjacent microlens, an opening may be provided in a middle position of a back focus of two adjacent microlenses in the plurality of microlenses in a non-bottom light blocking layer in the plurality of light blocking layers, so that two light guide channels corresponding to the two adjacent microlenses pass through the openings corresponding to the two adjacent microlenses in the non-bottom light blocking layer.

For example, as shown in fig. 3 and 7, for the second microlens 212, the first light blocking layer 220 may be provided with a second opening 222 at an intermediate position of the back focus of the first microlens 211 and the back focus of the second microlens 212, and each of the first microlens 211 and the second microlens 212 may have one light guide passage passing through the second opening 222; similarly, the first light blocking layer 220 may be provided with a third opening 223 at an intermediate position of the rear focal point of the third microlens 213 and the rear focal point of the second microlens 212, and one light guide channel of each of the third microlens 213 and the second microlens 212 may pass through the third opening 223.

In other implementations, the apertures of the openings corresponding to the same microlens in different light blocking layers may also be sequentially increased, decreased, or unchanged from top to bottom to screen out the optical signal that the optical sensing pixel array 240 is expected to receive.

For example, as shown in fig. 7, for three light blocking layers from top to bottom, the aperture of the opening of the third light blocking layer 260 of the upper layer is larger than the aperture of the opening of the first light blocking layer 220 of the middle layer, and the aperture of the opening of the first light blocking layer 220 of the middle layer is larger than the aperture of the opening of the second light blocking layer 230 of the lower layer.

Alternatively, the above description has been given by taking the example in which the fingerprint detection unit 20 includes two or three light blocking layers, respectively, and similarly, the fingerprint detection unit 20 may further include more light blocking layers, or the fingerprint detection unit 20 may also include only one light blocking layer, and the embodiment of the present application is not limited thereto.

For example, in the case where the fingerprint detection unit 20 includes only one light blocking layer, a plurality of inclined through holes may be provided on the one light blocking layer, that is, a plurality of light guide channels of any one microlens may be a plurality of inclined through holes corresponding to the microlens on the light blocking layer. For example, the thickness of the light blocking layer is greater than a preset threshold value, so that a plurality of optical sensing pixels arranged below each microlens are respectively used for receiving optical signals converged by the same microlens or converged by a plurality of adjacent microlenses and transmitted through corresponding light guide channels.

Optionally, the fingerprint detection unit 20 according to an embodiment of the present application may further comprise a transparent medium layer 250. Wherein, as shown in fig. 3, 4 and 7, the transparent dielectric layer 250 may be disposed at least one of the following positions: between the microlens array 210 and the at least one light blocking layer, between the at least one light blocking layer, and between the at least one light blocking layer and the optical sensing pixel array 240.

For example, as shown in fig. 3 and 4, the transparent dielectric layer 250 may include a first dielectric layer 251 between the microlens array 210 and the at least one light blocking layer (i.e., the first light blocking layer 220) and a second dielectric layer 252 between the first light blocking layer 220 and the second light blocking layer 230.

As another example, as shown in fig. 7, the transparent dielectric layer 250 may include: a first dielectric layer 251 between the microlens array 210 and the at least one light blocking layer (i.e., the third light blocking layer 260) and a second dielectric layer 252 between the three light blocking layers, wherein the second dielectric layer 252 includes the second dielectric layer 252 between the third light blocking layer 260 and the first light blocking layer 220 and the second dielectric layer 252 between the first light blocking layer 220 and the second light blocking layer 230.

The material of the transparent dielectric layer 250 is any transparent material transparent to light, such as glass, or may be air or vacuum transition, which is not particularly limited in the present application.

Optionally, the fingerprint detection unit 20 according to an embodiment of the present application may further comprise a filter layer. Fig. 8 is another schematic structural diagram of the fingerprint detection unit 20 according to an embodiment of the present application, and as shown in fig. 8, the fingerprint detection unit 20 may further comprise a filter layer 270, wherein the filter layer 270 may be disposed at least one of the following positions: above the microlens array 210, between the microlens array 210 and the at least one light blocking layer; the at least one light blocking layer; and between the at least one light blocking layer and the photo-sensing pixel array 240. For example, the filter layer 270 may be disposed between the optical sensing pixel array 240 and the second light blocking layer 230. For example, the filter layer 270 may be a filter layer in the optical assembly 132 referred to above.

The filter layer 270 may be used to reduce unwanted ambient light in fingerprint sensing to enhance the optical sensing of the received light by the optical sensing pixel array 240. The filter layer 270 may be particularly used to filter out light of a specific wavelength, for example, near infrared light and a portion of red light, etc. For example, if a human finger absorbs a large portion of the energy of light having a wavelength below 580nm, if one or more optical filters or optical filter layers are designed to filter light having wavelengths from 580nm to infrared, the impact of ambient light on optical detection in fingerprint sensing may be greatly reduced.

For example, the filter layer 270 may include one or more optical filters, which may be configured, for example, as bandpass filters, to allow transmission of light emitted by the OLED screen while blocking other light components, such as infrared light, in sunlight. Such optical filtering can effectively reduce the background light caused by sunlight when the fingerprint detection unit 20 is used outdoors. The one or more optical filters may be implemented, for example, as an optical filter coating formed on one or more continuous interfaces, or may be implemented as one or more discrete interfaces. It should be appreciated that the filter layer 270 may be fabricated at any location along the optical path to the optical sensor pixel array 240 via the reflected light from the finger, as embodiments of the application are not limited in this regard.

In addition, the light-entering surface of the filter layer 270 may be provided with an optical inorganic coating or an organic blackening coating, so that the reflectivity of the light-entering surface of the filter layer 270 is lower than a first threshold, for example, 1%, so that the optical sensing pixel array 240 can be ensured to receive enough light signals, and further fingerprint identification effect is improved.

The filter layer 270 is fixed on the upper surface of the optical sensing pixel array 240 by a fixing device. The filter layer 270 and the optical sensing pixel array 240 may be fixed by dispensing in a non-photosensitive area of the optical sensing pixel array 240, and a gap exists between the filter layer 270 and the photosensitive area of the optical sensing pixel array 240. Or the lower surface of the filter layer 270 is fixed on the upper surface of the optical sensing pixel array 240 by glue having a refractive index lower than a preset refractive index, for example, the preset refractive index includes but is not limited to 1.3.

Therefore, the fingerprint detection device of the embodiment of the application comprises a plurality of fingerprint detection units, and each fingerprint detection unit is set based on the technical scheme, so that at least the following technical problems can be solved: 1. the problem that the recognition effect of the vertical light signal on the dry finger is poor; 2. the problem of overlong exposure time of a single object space telecentric microlens array scheme; 3. the problem of excessive thickness of the fingerprint detection device; 4. the tolerance of the fingerprint detection device is too bad; 5. the fingerprint detection device is oversized.

Aiming at the problem 1, a plurality of light guide channels are designed for each microlens, and the included angle between each light guide channel in the plurality of light guide channels corresponding to each microlens and the optical axis of the corresponding microlens is smaller than 90 degrees, and correspondingly, a plurality of optical sensing pixels under each microlens can respectively receive oblique light signals converged by the same microlens or a plurality of adjacent microlenses and transmitted through the corresponding light guide channels, so that fingerprint information of a dry finger can be detected by utilizing the oblique light signals. When the contact between the dry finger and the OLED screen is poor, the contrast between the fingerprint ridges and the fingerprint valleys of the fingerprint image in the vertical direction is poor, and the fingerprint lines cannot be distinguished from the image blurring. Under normal living scenes, such as hand washing, getting up in the morning, finger plastering, low temperature, etc., the fingers are usually dry, the horny layer is uneven, and poor contact can occur in local areas of the fingers when the fingers are pressed on an OLED screen. The present application has the beneficial effects of raising the imaging effect of dry finger print and making the dry finger print clear.

In addition, the photo-sensing pixel array 240 can also expand the field angle and field of view of the optically sensitive pixel array 240 by receiving oblique light signals, e.g., the field of view of the fingerprint detection unit 20 that can receive oblique light can be made from 6x9mm ² Extended to 7.5x10.5mm ² Further promote fingerprint identification effect.

In addition, a plurality of optical sensing pixels are arranged below each micro lens, so that the space period of the lens array 210 is unequal to the space period of the optical sensing pixel array 240, and moire fringes in the fingerprint image can be avoided and the fingerprint identification effect can be improved.

For problem 2, by designing a plurality of light guide channels for each microlens, and each light guide channel corresponds to an optical sensing pixel, an imaging light path in which a single microlens is matched with multiple optical sensing pixels can be formed to receive the light signal passing through the light guide channel. That is, light signals of multiple angles can be multiplexed through a single microlens (for example, as shown in fig. 5 or 6, light signals of 4 angles can be multiplexed through a single microlens), so that light beams of different object space aperture angles can be split and imaged, the light inlet amount of each fingerprint detection unit is effectively improved, the light inlet amount of the fingerprint detection device is improved, and the exposure time of the optical sensing pixel array can be reduced. The larger the aperture angle of the microlens, the larger the amount of light entering the microlens, which is proportional to the effective diameter of the microlens and inversely proportional to the distance of the focal point.

Specifically, since the plurality of optical sensing pixels under each microlens can respectively receive the oblique light signals transmitted by the corresponding light guide channel, the optical sensing pixel array can be divided into a plurality of optical sensing pixel groups according to the direction of the light guide channel, wherein each optical sensing pixel in each optical sensing pixel group is used for receiving the oblique light signals with the same direction as the direction of the light guide channel corresponding to the same optical sensing pixel group, that is, each optical sensing pixel group can generate one fingerprint image based on the received oblique light signals, so that the plurality of optical sensing pixel groups can be used for generating a plurality of fingerprint images, in this case, the plurality of fingerprint images can be overlapped to obtain one fingerprint image with high resolution, and fingerprint identification can be performed based on the fingerprint image with high resolution.

Referring to fig. 5 or fig. 6, the optical sensing pixel array 240 may respectively converge oblique optical signals to 4 optical sensing pixels through the 4 light guide channels corresponding to each microlens, that is, the optical sensing pixel array 240 may be divided into 4 optical sensing pixel groups to form 4 fingerprint images, and based on the 4 fingerprint images, a fingerprint image with higher resolution may be obtained, so as to further improve fingerprint identification effect.

Therefore, as each micro lens can converge inclined light signals to a plurality of directions through a plurality of light guide channels, or the optical sensing pixel array can acquire a plurality of fingerprint images simultaneously through light path design, even if the exposure time of the optical sensing pixel array is reduced, the resolution ratio of each fingerprint image is lower, the fingerprint images with lower resolution ratio can be processed, and a fingerprint image with higher resolution ratio can be obtained.

That is, based on the above-described technical solution, the exposure time of the optical sensing pixel array 240 (i.e., the image sensor) can be reduced while ensuring the fingerprint recognition effect.

Aiming at the problem 3, the imaging light path matched with the multi-optical sensing pixels through the single micro lens can carry out non-right light imaging (namely oblique light imaging) on the object side light beam of the fingerprint under the screen, and particularly, the plurality of optical sensing pixels arranged below each micro lens are respectively used for receiving the light signals converged by the adjacent micro lenses, so that the object side numerical aperture of the optical system can be enlarged, the thickness of the light path design (namely the at least one light blocking layer) of the optical sensing pixel array can be shortened, and finally, the thickness of each fingerprint detection unit can be effectively reduced, and the thickness of the fingerprint detection device is reduced.

Aiming at the problem 4, the imaging light path matched with the multi-optical sensing pixels through the single micro lens can carry out non-positive light imaging on the object beam of the fingerprint under the screen, so that the object numerical aperture of the optical system can be enlarged, and the robustness of the system and the tolerance of the fingerprint detection unit 20 are improved. Wherein the numerical aperture may be a product of a refractive index (h) of a medium between a front lens of the microlens and the object to be inspected and a sine of half of an aperture angle (u).

Aiming at the problem 5, through the imaging light path matched by a single micro lens and multiple optical sensing pixels and the light guide channel arranged in the at least one light blocking layer, the density of the optical sensing pixels in the optical sensing pixel array 240 can be improved under the condition that two adjacent optical sensing pixels are not mutually influenced, so that the size of each fingerprint detection unit can be reduced, and the size of the fingerprint detection device is reduced.

As can be seen from the above, the technical solution of the present application can make the optical sensing pixel array 240 only receive the optical signals with oblique angles through reasonable design of the plurality of light guide channels corresponding to each microlens, and collect the oblique optical signals with multiple angles through a single microlens, thereby solving the problem of overlong exposure time of the single-object-space telecentric microlens array solution. In other words, the fingerprint detection unit 20 can solve the problems of too large thickness, too poor tolerance and too large size of the fingerprint detection device including a plurality of fingerprint detection units, as well as the problems of too poor recognition effect of the vertical light signal on the dry finger and too long exposure time of the single object space telecentric microlens array scheme.

In the embodiment of the present application, the fingerprint detection device includes a plurality of fingerprint detection units, each fingerprint detection unit may receive oblique light in a plurality of different directions, for example, the fingerprint detection unit 20 shown in fig. 3 to 8 may receive light in four different oblique directions, and the oblique angles in each direction may be the same or different.

Assuming that only one fingerprint detection unit is included in the off-screen fingerprint detection device, the fingerprint detection unit may be adapted to receive light in a plurality of directions that are inclined, in which case the effective imaging field of view of the single fingerprint detection unit will be offset outwardly in its perpendicular direction by a certain distance. For example, fig. 9 shows a schematic view of the field of view of a single fingerprint detection unit, as shown in fig. 9, the electronic device comprises a display screen 310, and a single fingerprint detection unit is included below the display screen 310, which is assumed to be the fingerprint detection unit 20 in fig. 3-8 described above, and which may receive four different oblique directions of light. As shown in fig. 9, since the fingerprint detection unit can receive light in an oblique direction, the size of the upper surface of the fingerprint detection unit (or the field of view of the fingerprint detection unit) is smaller than the area of the effective area of the fingerprint detection area 311 above the display screen 310, that is, the size of the entire fingerprint detection unit is extended outward by Δl with respect to the field of view of the fingerprint detection area 311 on the display screen 310. The effective area of the fingerprint detection area 311 included in the display screen 310 is also referred to as a field of view of the fingerprint detection unit in the fingerprint detection area 311 or a field of view of the fingerprint detection area 311, which refers to a range of effective touches when a finger touches a fingerprint for fingerprint recognition. It will be appreciated that the field of view of the flare is proportional to the distance between the upper surface of the screen and the upper surface of the fingerprint detection unit.

Specifically, fig. 10 is a schematic diagram showing a manner of calculating a field of view range of a single fingerprint detection unit according to an embodiment of the present application, and as shown in fig. 10, the size of the entire fingerprint detection unit 20 is expanded by Δl with respect to the field of view range of the fingerprint detection area 311 on the display screen 310, the Δl may be calculated by the following formula (1):

ΔL＝h ₁ tanθ ₁ +h ₂ tanθ ₂ (1)

wherein, as shown in FIG. 10, h ₁ Is the thickness of the display screen 310; θ ₁ The deflection angle at which light propagates within display screen 310; h is a ₂ Is the thickness of the gap between the fingerprint detection unit 20 and the display screen 310; θ ₂ Is the deflection angle of the light propagating in the gap, e.g. θ when the gap is air ₂ Is the deflection angle of light propagating in air. Alternatively, the θ ₁ And theta ₂ Satisfy formula n ₁ sinθ ₁ ＝n ₂ sinθ ₂ ，n ₁ Representing the refractive index, n, of the display screen 310 ₂ Representing the refractive index of the gap between the fingerprint detection unit 20 and the display screen 310, e.g. if the gap is air, then n ₂ Representing the refractive index of air.

For example, assuming four different oblique directions of light received by the fingerprint detection unit, each direction is at an angle of 40 ° in air, the display screen 310 is an OLED screen having a thickness of 1.4mm. At this time, when the fingerprint detection unit 20 is installed under the display screen 310, the field of view of the fingerprint detection unit's flare may be adjusted to Δl=0.75 mm by adjusting the distance between the fingerprint detection unit 20 and the display screen 310.

In general, the smaller the chip of the fingerprint detection unit, the larger the ratio of the field of view of its outer expansion. For example, assuming a fingerprint sensing unit of minimum size of 2.3mm x2.3mm, which may be the size of the complementary metal oxide semiconductor (Complementary Metal Oxide Semiconductor, CMOS) photosensitive area, the optical path through the fingerprint sensing unit involves extending its field of view effective area to 3.8mm x 3.8mm, and extending the entire field of view area approximately 2.7 times.

According to the experience of using the off-screen fingerprint, the effective area of the under-screen optical fingerprint is usually greater than or equal to 6mmx6mm, and the recognition effect is better, that is, the effective area of the fingerprint detection area 311 included in the display screen 310 is usually greater than or equal to 6mmx6mm, and the fingerprint detection area 311 is used for providing a touch interface for fingerprint recognition of a user. In order to obtain as many fields of view as possible with the smallest possible chip area, therefore, the embodiment of the application provides a fingerprint detection device, which realizes a larger field of view by physically splicing a plurality of fingerprint detection units.

Specifically, the fingerprint detection device according to the embodiment of the present application includes a plurality of fingerprint detection units, fig. 11 shows a schematic diagram of an electronic device 300 according to the embodiment of the present application, as shown in fig. 11, the electronic device 300 includes a display screen 310, the display screen 310 includes a fingerprint detection area 311 for providing a touch interface for fingerprint recognition of a user, and the fingerprint detection device is disposed below the display screen 310, and includes a plurality of fingerprint detection units, for example, any one of the fingerprint detection units may be the fingerprint detection unit 20 described above.

Specifically, the size of each fingerprint detection unit of the plurality of fingerprint detection units and the distance between two adjacent fingerprint detection units are set according to a size parameter comprising at least one of the following parameters: the field of view range of each fingerprint detection unit (i.e. the total area of the field of view including the fields of view that the fingerprint detection units can expand), the area of the fingerprint detection area, the thickness of the display screen, and the distance from the upper surface of the optical path of each fingerprint detection unit to the upper surface of the display screen.

It should be understood that the structures or sizes of the plurality of fingerprint detection units included in the fingerprint detection device according to embodiments of the present application may be the same or different. Specifically, any one of the fingerprint detection units may be the fingerprint detection unit 20 in fig. 3 to 8, but the fingerprint detection units may be fingerprint detection units having the same or different structures, and may be fingerprint detection units having the same or different sizes. For example, in order to facilitate the production process, the structures and dimensions of the fingerprint detection units may be all identical, for example, the fingerprint detection units may be the fingerprint detection unit 20 shown in fig. 3 or fig. 7, but the embodiment of the present application is not limited thereto.

In an embodiment of the present application, a plurality of fingerprint detection units included in the fingerprint detection device may be arranged as a matrix of n×m, where n and m are positive integers. Wherein, the spacing distances of a plurality of fingerprint detection units positioned in the same row are equal; and/or the interval distances of a plurality of fingerprint detection units positioned in the same column in the plurality of fingerprint detection units are equal.

Alternatively, the arrangement of the plurality of fingerprint detection units according to embodiments of the present application will be described in detail below in connection with specific embodiments.

Alternatively, as the first embodiment, the fingerprint detection device may include two fingerprint detection units.

Alternatively, the two fingerprint detection units may be arranged side by side left and right, or may be arranged side by side up and down. For example, fig. 12 is a schematic diagram showing the arrangement of two fingerprint detection units according to an embodiment of the present application. As shown in fig. 12, it is assumed here that two rectangular fingerprint detection units are arranged side by side, wherein each fingerprint detection unit may be the fingerprint detection unit 20 shown in fig. 3 to 8 described above.

Specifically, as shown in fig. 12, where the width of the fingerprint detection unit is denoted as W, the length is denoted as H, the horizontal distance between the two fingerprint detection units is denoted as G, the rectangular box at the periphery of the two fingerprint detection units in fig. 12 may represent the effective range of the fingerprint detection area, which is larger than the area of the fingerprint detection unit. Alternatively, the actual area of the fingerprint detection area may be larger than the effective range thereof, where the effective range represents the smallest area that can be used for fingerprint recognition, for example, other functional areas may be further disposed in the fingerprint detection area, and the embodiment of the present application is not limited thereto.

It should be understood that, as shown in fig. 12, according to the size of the field of view of each fingerprint detection unit on the upper surface of the display screen, in the case where two fingerprint detection units are provided, by reasonably setting the sizes of W, H and G, it is possible to satisfy the requirement of the effective area size of the fingerprint detection area.

Specifically, the size parameters include: in the case that the field of view of the upper surface of the display screen of each fingerprint detection unit extends by at least a first value X (i.e. Δl is greater than or equal to the first value X), and the length of the fingerprint detection area is greater than or equal to a second value Y, and the width of the fingerprint detection area is greater than or equal to a third value Z, then referring to fig. 12, the following parameters may be set correspondingly: the length H of each fingerprint detection unit is greater than or equal to Y-2X, the width W of each fingerprint detection unit is greater than or equal to 0.5Z-2X, and the horizontal distance G between the two fingerprint detection units is less than or equal to 2X.

For example, assume that the size parameters include: the field of view of each fingerprint detection unit on the upper surface of the display screen ranges from at least 0.75mm (i.e. Δl is greater than or equal to 0.75 mm) to the edge of each fingerprint detection unit, and the area of the fingerprint detection area is greater than or equal to 6mm by 6mm, then referring to fig. 12, the following parameters may be set correspondingly: the length H of each fingerprint detection unit is greater than or equal to 4.5mm, the width W of each fingerprint detection unit is greater than or equal to 1.5mm, and the horizontal distance G between the two fingerprint detection units is less than or equal to 1.5mm. For example, the length H of each fingerprint detection unit is set to 6mm, the width W of each fingerprint detection unit is set to 2.3mm, and the horizontal distance G between the two fingerprint detection units is set to 1mm, so that the effective field of view or effective area of the corresponding fingerprint identification area is 7.1mm by 7.5mm according to the above parameter settings.

As another example, assume that the size parameters include: the field of view of each fingerprint detection unit on the upper surface of the display screen ranges from the edge of each fingerprint detection unit to at least 0.6mm (i.e. Δl is greater than or equal to 0.6 mm), and the area of the fingerprint detection area is greater than or equal to 6mm x 6mm, then referring to fig. 12, the following parameters may be set correspondingly: the length H of each fingerprint detection unit is greater than or equal to 4.8mm, the width W of each fingerprint detection unit is greater than or equal to 1.8mm, and the horizontal distance G between the two fingerprint detection units is less than or equal to 1.2mm. For example, the length H of each fingerprint detection unit is set to 6.5mm, the width W of each fingerprint detection unit is set to 2.6mm, and the horizontal distance G between the two fingerprint detection units is set to 1mm, so that the effective field of view or effective area of the corresponding fingerprint identification area is 7.4mm by 7.7mm according to the above parameter settings.

As another example, assume that the size parameters include: the field of view of each fingerprint detection unit on the upper surface of the display screen ranges from at least 0.3mm (i.e. Δl is greater than or equal to 0.3 mm) to the edge of each fingerprint detection unit, and the area of the fingerprint detection area is greater than or equal to 6mm by 6mm, then referring to fig. 12, the following parameters may be set correspondingly: the length H of each fingerprint detection unit is greater than or equal to 5.4mm, the width W of each fingerprint detection unit is greater than or equal to 2.4mm, and the horizontal distance G between the two fingerprint detection units is less than or equal to 0.6mm.

It will be appreciated that the distance DeltaL that each fingerprint detection unit expands outwardly relative to the edge of each fingerprint detection unit over the field of view of the upper surface of the display screen may be calculated according to equation (1) by the parameter h ₁ 、h ₂ 、θ ₁ And theta ₂ The determination is made, and the range of Δl may be set according to the actual application, for example, 0.6mm or 0.75mm as described above may be set, or may be set to a larger or smaller value, for example, Δl is generally set to 0.3mm or more. For example, assume that the thickness h of the display screen ₁ At a deflection angle θ of 1.4mm, the light propagates in air ₂ Is 40 DEG, and the vertical distance h between the upper surface of the light path of the fingerprint detection unit and the display screen is adjusted ₂ Δl may be made to reach 0.6mm, or to reach 0.75mm; for another example, assume that the vertical distance h from the light path upper surface of each fingerprint detection unit to the upper surface of the display screen ₁ +h ₂ At a deflection angle θ of 1.6mm, the light propagates in air ₂ At 20 °, Δl may be set to 0.6mm.

Therefore, according to the above-mentioned mode of setting two fingerprint detection units, namely the method of splicing the double light sensitive areas, three parameters W, G and H are reasonably set so as to meet the requirement of the effective area of the fingerprint detection area, and the low-cost under-screen optical fingerprint identification scheme can be realized. According to the splicing method, the data output by the areas of the two fingerprint detection units can splice the whole view fields through a digital image processing algorithm, so that fingerprint identification is performed.

Alternatively, as a second embodiment, the number of the plurality of fingerprint detection units included in the fingerprint detection device may be four.

Alternatively, the four fingerprint detection units may be arranged in a variety of ways. For example, four fingerprint detection units may be arranged in a row or column, or four fingerprint detection units may be arranged in a matrix of 2×2.

Fig. 13 is a schematic diagram showing the arrangement of four fingerprint detection units according to an embodiment of the present application. As shown in fig. 13, it is assumed here that four rectangular fingerprint detection units are arranged in a matrix of 2×2, where each fingerprint detection unit may be the fingerprint detection unit 20 shown in fig. 3 to 8 described above.

Specifically, as shown in fig. 13, the length of each fingerprint detection unit is denoted herein as H, the width of each fingerprint detection unit is denoted as W, the horizontal distance between two fingerprint detection units adjacent in the horizontal direction is denoted as G1, and the vertical distance between two fingerprint detection units adjacent in the vertical direction is denoted as G2. The rectangular boxes around the four fingerprint detection units in fig. 13 may represent the effective range of the fingerprint detection area, which is larger than the total area of the fingerprint detection units. Alternatively, the actual area of the fingerprint detection area may be larger than the effective range thereof, where the effective range represents the smallest area that can be used for fingerprint recognition, for example, other functional areas may be further disposed in the fingerprint detection area, and the embodiment of the present application is not limited thereto.

It should be understood that, as shown in fig. 13, according to the size of the field of view of each fingerprint detection unit on the upper surface of the display screen, in the case of providing four fingerprint detection units, by reasonably setting the sizes of W, H, G and G2, it is possible to satisfy the requirement of the effective area size of the fingerprint detection area. For example, the size and distance of each fingerprint detection unit may be determined based on the distance that the field of view of each fingerprint detection unit on the upper surface of the display screen expands outward relative to the edge of each fingerprint detection unit, and the minimum value of the effective area of the fingerprint detection area in the display screen, so as to meet the requirements of the fingerprint detection area.

Specifically, the size parameters include: in the case that the field of view of the upper surface of the display screen of each fingerprint detection unit extends by at least a first value X (i.e. Δl is greater than or equal to the first value X), and the length of the fingerprint detection area is greater than or equal to a second value Y, and the width of the fingerprint detection area is greater than or equal to a third value Z, then referring to fig. 13, the following parameters may be set correspondingly: the length H of each fingerprint detection unit is larger than or equal to 0.5Y-2X, the width W of each fingerprint detection unit is larger than or equal to 0.5Z-2X, the horizontal distance G1 between two adjacent fingerprint detection units in the horizontal direction is smaller than or equal to 2X, and the vertical distance G2 between two adjacent fingerprint detection units in the vertical direction is smaller than or equal to 2X.

For example, assume that the dimensional parameters of an embodiment of the present application include: the field of view of each fingerprint detection unit on the upper surface of the display screen is at least 0.75mm (i.e. Δl is greater than or equal to 0.75 mm) and the area of the fingerprint detection area is greater than or equal to 6mm x 6mm, then referring to fig. 13, the following parameters may be set correspondingly: the length H of each fingerprint detection unit may be set to be greater than or equal to 1.5mm, the width W of each fingerprint detection unit may be set to be greater than or equal to 1.5mm, the horizontal distance G1 between two fingerprint detection units adjacent in the horizontal direction may be set to be less than or equal to 1.5mm, and the vertical distance G2 between two fingerprint detection units adjacent in the vertical direction may be set to be less than or equal to 1.5mm.

For example, according to the above-mentioned dimensional parameters, the length H of each fingerprint detection unit may be set to 2.3mm, the width W of each fingerprint detection unit is set to 2.3mm, the horizontal distance G1 between two adjacent fingerprint detection units in the horizontal direction is set to 1.2mm, and the vertical distance G2 between two adjacent fingerprint detection units in the vertical direction is set to 1.2mm, then the effective area of the four-electron-beam eye stitching scheme is (2.3x2+1.2+1.5) ² ＝7.3×7.3(mm ² )。

As another example, assume that the dimensional parameters of an embodiment of the present application include: the field of view of each fingerprint detection unit on the upper surface of the display screen is at least 0.6mm (i.e. Δl is greater than or equal to 0.6 mm) and the area of the fingerprint detection area is greater than or equal to 6mm x 6mm, then referring to fig. 13, the following parameters may be set correspondingly: the length H of each fingerprint detection unit may be set to be greater than or equal to 1.8mm, the width W of each fingerprint detection unit may be set to be greater than or equal to 1.8mm, the horizontal distance G1 between two fingerprint detection units adjacent in the horizontal direction may be set to be less than or equal to 1.2mm, and the vertical distance G2 between two fingerprint detection units adjacent in the vertical direction may be set to be less than or equal to 1.2mm.

FIG. 14 is a schematic view showing the arrangement of four fingerprint detection units according to the embodiment of the present application, as shown in FIG. 14, according to the case that the field of view of each fingerprint detection unit on the upper surface of the display screen is 0.6mm in the edge of each fingerprint detection unit, the length H of each fingerprint detection unit may be set to 2.6mm, the width W of each fingerprint detection unit may be set to 2.6mm, the horizontal distance G1 between two adjacent fingerprint detection units in the horizontal direction may be set to 1mm, and the vertical distance G2 between two adjacent fingerprint detection units in the vertical direction may be set to 1mm, so that the effective area of the fingerprint detection area is (2.6X12+1+1.2) ² ＝7.4×7.4(mm ² ) The fingerprint detection area meets the requirement that the area of the fingerprint detection area is larger than or equal to 6mm and 6mm.

As another example, assume that the dimensional parameters of an embodiment of the present application include: the field of view of each fingerprint detection unit on the upper surface of the display screen is at least 0.3mm (i.e. Δl is greater than or equal to 0.3 mm) and the area of the fingerprint detection area is greater than or equal to 6mm x 6mm, then referring to fig. 13, the following parameters may be set correspondingly: the length H of each fingerprint detection unit may be set to be greater than or equal to 2.4mm, the width W of each fingerprint detection unit may be set to be greater than or equal to 2.4mm, the horizontal distance G1 between two fingerprint detection units adjacent in the horizontal direction may be set to be less than or equal to 0.6mm, and the vertical distance G2 between two fingerprint detection units adjacent in the vertical direction may be set to be less than or equal to 0.6mm.

It will be appreciated that, similarly to when two fingerprint detection units are provided, whether several fingerprint detection units are provided, the field of view of each fingerprint detection unit at the upper surface of the display screen extends over a distance DeltaL relative to the edge of each fingerprint detection unit, by a parameter h according to equation (1) ₁ 、h ₂ 、θ ₁ And theta ₂ The determination is made, and the range of Δl may be set according to practical applications, for example, the foregoing 0.6mm or 0.75mm may be set, or may also be set to a larger or smaller value, for example, Δl is generally set to be greater than or equal to 0.3mm, which is not described herein for brevity.

According to the above two embodiments, the fingerprint detection device may include two or four fingerprint detection units by using a stitching manner, on the basis of which other numbers of fingerprint detection units may be further provided, for example, more than 4 fingerprint detection units may be further provided, and the embodiment of the present application is not limited thereto.

In addition, the splicing scheme of the fingerprint detection unit can be carried out on a single CMOS imaging chip, and can also be realized by splicing a plurality of CMOS imaging chips with small-area fingerprint detection units and light path structures, and the two can realize low-cost, large-field-of-view-area and ultra-thin-screen optical fingerprints.

In the embodiment of the application, the data output by each fingerprint detection unit can be processed by a digital image reconstruction algorithm. Specifically, image data in the same direction of a sensing area of each fingerprint detection unit is shifted by a specific pixel, so that a clearest image of the area is obtained; images of the same corresponding area of different fingerprint detection units can be spliced by moving specific pixels to obtain the clearest image. Interpolation can be used in the splicing process to solve the problem of different sampling of the image data in the non-overlapping area. Compared with a single object space telecentric microlens array scheme, the fingerprint identification device provided by the embodiment of the application has the advantages that the areas of a plurality of fingerprint detection units are smaller, the obtained data volume is smaller, and the software resource consumption is smaller under the same field of view. In addition, the intervals between the AA areas of the fingerprint detection units can be used for layout wiring, or can also be used for placing a driving circuit and a control circuit of the CMOS sensitive unit pixels, so that the area of a chip can be further reduced.

For convenience of explanation, the description will be made herein taking as an example a manner in which an image is processed by an optical sensing pixel array included in one fingerprint detection unit, and each of a plurality of fingerprint detection units included in the fingerprint detection device may perform image processing in the same manner.

Specifically, for a fingerprint detection unit, the fingerprint detection unit includes an optical sensing pixel array, where the optical sensing pixel array includes a plurality of optical sensing pixels, the plurality of optical sensing pixels are divided into a plurality of groups of optical sensing pixels, and the same group of optical sensing pixels are used for receiving optical signals in the same direction, that is, directions of light guide channels through which the optical signals received by the same group of optical sensing pixels pass are the same.

The optical sensing pixel array is divided into a plurality of groups of optical sensing pixels, and the groups of optical sensing pixels are used for receiving light signals in a plurality of directions to obtain a plurality of images, and the images are used for detecting fingerprint information of the finger. For example, each fingerprint detection unit may directly output the plurality of images, or may reconstruct the plurality of images into one image, the reconstructed image being used for fingerprint identification.

Optionally, one of the plurality of sets of optical sensing pixels is configured to receive an optical signal in one of the plurality of directions to obtain one of the plurality of images. For example, as shown in fig. 5, assuming that the array of photo sensing pixels in the fingerprint detection unit can receive light in four directions in total, that is, the fingerprint detection unit includes four light guiding channels, the array of photo sensing pixels may be divided into four groups of photo sensing pixels, wherein a first group of photo sensing pixels is used to receive light signals in a first direction, for example, the first group of photo sensing pixels may include photo sensing pixels included in the upper left corner in fig. 5, and is converted into a first group of electrical signals, and the first group of electrical signals is used to form a first image; by analogy, a second set of photo-sensing pixels is used to receive the light signal in a second direction, e.g., the second set of photo-sensing pixels may comprise the photo-sensing pixels included in the upper right corner of fig. 5 and are converted into a second set of electrical signals that are used to form a second image; a third set of photo-sensing pixels for receiving light signals in a third direction, e.g. the third set of photo-sensing pixels may comprise photo-sensing pixels comprised in the lower left corner of fig. 5, and converting into a third set of electrical signals for forming a third image, and a fourth set of photo-sensing pixels for receiving light signals in a fourth direction, e.g. the fourth set of photo-sensing pixels may comprise photo-sensing pixels comprised in the lower right corner of fig. 5, and converting into a fourth set of electrical signals for forming a fourth image.

Alternatively, the number of pixels in each of the plurality of groups of optically sensitive pixels may be equal or unequal; if the numbers of the groups of optical sensing pixels are equal, the same arrangement mode can be adopted. For example, as shown in fig. 5, assuming that four optical sensing pixels are correspondingly distributed under each microlens like the second microlens 212, when the optical sensing pixel arrays are grouped, the optical sensing pixels on the upper left of each microlens may be grouped into the same group, and the optical signal directions received by the optical sensing pixels of the same group are the same; similarly, a total of four groups of the photo-sensing pixels may be divided into four groups, and the four groups of the photo-sensing pixels may be arranged in the same manner and located at positions corresponding to the upper left corners of the microlenses.

It should be understood that, the optical sensing pixel array is divided into multiple groups of optical sensing pixels, and each optical sensing pixel in each group of optical sensing pixels may correspond to one pixel point in one image, that is, each optical sensing pixel in the optical sensing pixel array corresponds to only one pixel point, so that the corresponding generated image is clearer and the relative calculation amount is larger.

In view of reducing the calculation amount, alternatively, for any one of the groups of the optical sensing pixels, a pixel point may be generated by a plurality of optical sensing pixels. For example, assuming that the number of the optical sensing pixels included in the plurality of groups of optical sensing pixels is the same, a pixel point can be correspondingly output by a preset number of optical sensing pixels which are continuous in positions in one group of optical sensing pixels, so that the calculated amount can be greatly reduced.

The above-mentioned consecutive photo-sensing pixels in the same group of photo-sensing pixels outputting the same pixel point may not be adjacent to each other, that is, for any consecutive photo-sensing pixels outputting the same pixel point, there may be other photo-sensing pixels at positions between any two photo-sensing pixels in the consecutive plurality of photo-sensing pixels, but the directions of the light signals received by the other photo-sensing pixels are different from the directions of the light signals received by the consecutive plurality of photo-sensing pixels, that is, the following photo-sensing pixels may not exist at positions between any two photo-sensing pixels in the consecutive plurality of photo-sensing pixels: the direction of the light signal received by the optical sensing pixels is the same as the direction of the light signal received by the continuous plurality of optical sensing pixels.

For example, taking fig. 5 as an example, assuming that each microlens is identical to the second microlens 212 and corresponds to four photo-sensing pixels, the photo-sensing pixels in the upper left corner of each microlens belong to the same group, and for this group of photo-sensing pixels, one or more photo-sensing pixels consecutive to the third photo-sensing pixel 243 may include: among one or more microlenses adjacent to the second microlens 212 (e.g., the first microlens 211 and the third microlens 213 shown in fig. 3), an upper left corner of each microlens corresponds to an optically sensed pixel; meanwhile, one or more photo-sensing pixels consecutive to the third photo-sensing pixel 243 do not include: the photo-sensing pixels corresponding to the microlenses not adjacent to the second microlenses 212, for example, do not include photo-sensing pixels corresponding to any one of the microlenses separated by other microlenses from the second microlenses 212. And, the third photo-sensing pixel 243 and one or more photo-sensing pixels connected thereto may be used to output a pixel point together.

It will be appreciated that in the manner described above, each fingerprint detection unit may output one or more images, for example, the multiple images may be combined for fingerprint detection provided that the multiple fingerprint detection units ultimately each output one fingerprint image. Or if each fingerprint detection unit of the plurality of fingerprint detection units outputs a plurality of images, for example, the plurality of images correspond to the light signals in a plurality of directions, fingerprint images with the same light signals in all the images output by the plurality of fingerprint detection units can be combined, for example, image data in the same direction of a sensing area of each fingerprint detection unit is shifted by a specific pixel, so as to obtain the clearest image of the area; images of the same corresponding area of different fingerprint detection units can be spliced by moving specific pixels to obtain the clearest image.

In addition, the fingerprint detection device of the embodiment of the application can also be used for distinguishing true fingerprints from false fingerprints of 2D and 3D. Since each fingerprint detection unit can receive images in multiple directions, for example four directions. In the case where the valleys and ridges of the fingerprint are pressed against the upper surface of the OLED screen, when light is received in an oblique direction, the linearly polarized light is reflected by the upper surface of the OLED screen at the valleys to penetrate into the cell phone due to the characteristics of brewster's angle. When the reflected linear polarized light is parallel to the linear polaroid of the mobile phone, the light intensity received by the lower sensor is maximum; when the reflected linear polarized light is perpendicular to the direction of the linear polaroid of the mobile phone screen, the light received by the lower sensor is weakest. That is, the 3D fingerprint is pressed on the upper surface of the OLED screen, the original data of images in different directions of the electronic beam eye and the linear polaroid of the mobile phone screen are different, but the difference of the 2D fingerprint is not obvious. Thus, by distinguishing the differences of the raw data of the light in different directions, the 2D fake fingerprint and the 3D fingerprint can be distinguished to some extent.

Therefore, the fingerprint detection device provided by the embodiment of the application comprises a plurality of fingerprint detection units, and by reasonably splicing the fingerprint detection units, large view field and light oblique receiving can be realized, so that the actual chip area can be reduced, the chip cost is reduced, the software resource consumption is reduced, and the imaging effect of the dry fingerprint can be improved.

The embodiment of the application also provides electronic equipment which can comprise a display screen and the fingerprint detection device in the embodiment of the application, wherein the fingerprint detection device is arranged below the display screen so as to realize the optical fingerprint detection under the screen.

The electronic device may be any electronic device having a display screen.

The display screen may be a display screen in the above description, for example, an OLED display screen or other display screens, and the description of the display screen may refer to the description of the display screen in the above description, which is not repeated herein for brevity.

The electronic device may further comprise at least one processor for processing data output by the plurality of fingerprint detection units. For example, the electronic device may receive the image data output by each fingerprint detection unit via a processor, for example, via a serial peripheral interface (Serial Peripheral Interface, SPI), and process the data of the plurality of fingerprint detection units. Or, the electronic device may further receive the image data output by each fingerprint detection unit through SPI interfaces of a plurality of processors, and after each processor processes the image data respectively, the combination process is performed by one of the processors, which is not limited in the embodiment of the present application.

It should be understood that the specific examples of the embodiments of the present application are intended to facilitate a better understanding of the embodiments of the present application by those skilled in the art, 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 application and in the appended claims is for the purpose of describing particular embodiments only, and is not intended to be limiting of the embodiments of the application. For example, as used in the embodiments of the 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 various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the solution. 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.

It will be clear to those skilled in the art that, for convenience and brevity of description, specific working procedures of the above-described systems, apparatuses and units may refer to corresponding procedures in the foregoing method embodiments, and are not repeated herein.

In the several embodiments provided by the present application, it should be understood that the disclosed systems, devices, and methods may be implemented in other manners. For example, the apparatus embodiments described above are merely illustrative, e.g., the division of the units is merely a logical function division, and there may be additional divisions when actually implemented, e.g., multiple units or components may be combined or integrated into another system, or some features may be omitted or not performed. Alternatively, the coupling or direct coupling or communication connection shown or discussed with each other may be an indirect coupling or communication connection via some interfaces, devices or units, which may be in electrical, mechanical or other form.

The units described as separate units may or may not be physically separate, and units shown 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 may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

In addition, each functional unit in the embodiments of the present application may be integrated in one processing unit, or each unit may exist alone physically, or two or more units may be integrated in one unit.

The functions, if implemented in the form of software functional units and sold or used as a stand-alone product, may be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application may be embodied essentially or in a part contributing to the prior art or in a part of the technical solution, in the form of a software product stored in a storage medium, comprising several instructions for causing a computer device (which may be a personal computer, a server, a network device, etc.) to perform 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 (random access memory, RAM), a magnetic disk, or an optical disk, or other various media capable of storing program codes.

The foregoing is merely illustrative of the present application, and the present application is not limited thereto, and any person skilled in the art will readily recognize that variations or substitutions are within the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A fingerprint detection device, characterized in that is applicable to the below of display screen in order to realize the optical fingerprint detection under the screen, the display screen includes fingerprint detection area, fingerprint detection area is used for the finger touch in order to carry out fingerprint detection, fingerprint detection device includes:

a plurality of fingerprint detection units, the smallest dimension of each fingerprint detection unit of the plurality of fingerprint detection units and the largest distance between two adjacent fingerprint detection units being set according to a dimension parameter, the dimension parameter comprising at least one of the following parameters: the field of view range of each fingerprint detection unit, the area of the fingerprint detection area, the thickness of the display screen and the distance from the upper surface of the light path of each fingerprint detection unit to the lower surface of the display screen;

wherein the effective range of the fingerprint detection area is greater than or equal to the minimum value of the area of the fingerprint detection area, and the effective range is the minimum area for fingerprint identification;

wherein each fingerprint detection unit comprises:

a microlens array, configured to be disposed below the display screen, and including a plurality of microlenses;

the light blocking layer is arranged below the micro lens array, and is provided with a plurality of light guide channels corresponding to each micro lens in the plurality of micro lenses, and an included angle between each light guide channel in the plurality of light guide channels corresponding to each micro lens and the optical axis of each micro lens is smaller than 90 degrees;

The optical sensing pixel array is arranged below the at least one light blocking layer and comprises a plurality of optical sensing pixels, one optical sensing pixel is arranged below each of a plurality of light guide channels corresponding to each micro lens, and the one optical sensing pixel is used for receiving optical signals converged by the micro lenses and transmitted through the corresponding light guide channels and used for detecting fingerprint information of a finger.

2. The fingerprint detection device according to claim 1 wherein said plurality of fingerprint detection units are of the same size.

3. The fingerprint detection device according to claim 2 wherein a plurality of fingerprint detection units located in the same row of the plurality of fingerprint detection units are equally spaced apart; and/or the number of the groups of groups,

the spacing distances of the fingerprint detection units in the same column are equal.

4. The fingerprint detection device according to claim 1 wherein the number of the plurality of fingerprint detection units is two.

5. The fingerprint detection device according to claim 4 wherein two fingerprint detection units are arranged side by side.

6. The fingerprint detection device according to claim 5 wherein, at said dimensional parameter, comprises: and when the field of view of the upper surface of the display screen is that the edge of each fingerprint detection unit expands outwards by at least a first value X, the length of the fingerprint detection area is larger than or equal to a second value Y, and the width of the fingerprint detection area is larger than or equal to a third value Z, the length of each fingerprint detection unit is larger than or equal to Y-2X, the width of each fingerprint detection unit is larger than or equal to 0.5Z-2X, and the horizontal distance between the two fingerprint detection units is smaller than or equal to 2X.

7. The fingerprint detection device according to claim 1 wherein the number of fingerprint detection units is four.

8. The fingerprint detection device according to claim 7 wherein four fingerprint detection units are arranged in a matrix of 2x 2.

9. The fingerprint detection device according to claim 8, wherein the size parameter comprises: and when the field of view of the upper surface of the display screen is that the edge of each fingerprint detection unit expands outwards by at least a first value X, the length of the fingerprint detection area is larger than or equal to a second value Y, and the width of the fingerprint detection area is larger than or equal to a third value Z, the length of each fingerprint detection unit is larger than or equal to 0.5Y-2X, the width of each fingerprint detection unit is larger than or equal to 0.5Z-2X, the horizontal distance between two adjacent fingerprint detection units in the horizontal direction is smaller than or equal to 2X, and the vertical distance between two adjacent fingerprint detection units in the vertical direction is smaller than or equal to 2X.

10. The fingerprint detection device according to any one of claims 1 to 9 wherein,

the bottoms of the light guide channels corresponding to each microlens extend to the lower parts of the adjacent microlenses respectively; or alternatively, the process may be performed,

the bottoms of the light guide channels corresponding to each microlens are positioned below the same microlens.

11. The fingerprint detection device according to any one of claims 1 to 9 wherein the plurality of light guide channels corresponding to each microlens are centrally and symmetrically distributed along the optical axis direction of the same microlens.

12. The fingerprint detection device according to any one of claims 1-9 wherein each of the plurality of light guide channels corresponding to each microlens forms a preset included angle with a first plane, such that a plurality of optical sensing pixels disposed below each microlens are respectively configured to receive optical signals converged by the microlens and transmitted through the corresponding light guide channel, wherein the first plane is a plane parallel to the display screen.

13. The fingerprint sensing device according to claim 12, wherein said predetermined included angle is in the range of 15 degrees to 60 degrees.

14. The fingerprint sensing device according to claim 13, wherein the projections of said plurality of light guide channels corresponding to each microlens are symmetrically distributed with respect to the center of the projection of the optical axis of the same microlens on said first plane.

15. The fingerprint detection device according to claim 14 wherein said array of photo-sensing pixels comprises a plurality of groups of photo-sensing pixels, wherein the directions of light guide channels through which light signals received by the same group of photo-sensing pixels are identical, wherein said plurality of groups of photo-sensing pixels are configured to receive light signals in a plurality of directions to obtain a plurality of images, and wherein said plurality of images are configured to detect fingerprint information of a finger.

16. The fingerprint detection device according to claim 15 wherein one of said plurality of sets of photo-sensing pixels is configured to receive light signals in one of said plurality of directions to obtain one of said plurality of images.

17. The fingerprint sensing device according to claim 16, wherein the plurality of sets of pixels are equal in number and arrangement.

18. The fingerprint sensing device according to claim 16, wherein one of said plurality of sets of photo-sensing pixels corresponds to a pixel point in an image.

19. The fingerprint sensing device according to claim 16 wherein successive ones of said plurality of sets of photo-sensing pixels correspond to a pixel point in an image.

20. The fingerprint detection device according to any one of claims 1 to 9 wherein the distribution of the plurality of optically sensitive pixels under each microlens is rectangular or diamond shaped.

21. The fingerprint detection device according to any one of claims 1 to 9 wherein said at least one light blocking layer is a plurality of light blocking layers, and wherein at least one aperture corresponding to each microlens is provided in a different light blocking layer to form a plurality of light guiding channels corresponding to each microlens.

22. The fingerprint detection device according to claim 21, wherein the number of openings in different light blocking layers corresponding to the same microlens increases sequentially from top to bottom.

23. The fingerprint detection device according to claim 21, wherein the apertures of the openings in the different light blocking layers corresponding to the same microlens decrease sequentially from top to bottom.

24. The fingerprint detection device according to claim 21 wherein a plurality of openings corresponding to each microlens are provided in a bottom light blocking layer of the plurality of light blocking layers, and wherein a plurality of light guide channels corresponding to each microlens respectively pass through a plurality of openings corresponding to the same microlens in the bottom light blocking layer.

25. The fingerprint detection device according to claim 21 wherein a top light blocking layer of the plurality of light blocking layers is provided with openings on the optical axis of each microlens, and wherein the plurality of light guide channels corresponding to each microlens each pass through openings corresponding to the same microlens in the top light blocking layer.

26. The fingerprint detection device according to claim 21 wherein a non-underlying light blocking layer of the plurality of light blocking layers is provided with an aperture in a middle position of a back focal point of two adjacent microlenses of the plurality of microlenses, and wherein two light guide channels corresponding to the two adjacent microlenses each pass through the aperture corresponding to the two adjacent microlenses of the non-underlying light blocking layer such that bottoms of the plurality of light guide channels corresponding to each microlens extend below the adjacent plurality of microlenses, respectively.

27. The fingerprint detection device according to any one of claims 1 to 9 wherein said at least one light blocking layer comprises only one light blocking layer, said plurality of light guiding channels being a plurality of slanted through holes corresponding to the same microlens in said one light blocking layer.

28. The fingerprint detection device according to claim 27 wherein the thickness of said one light blocking layer is greater than a predetermined threshold such that a plurality of optically sensitive pixels disposed under each of said microlenses are respectively configured to receive optical signals collected via the microlenses and transmitted through the corresponding light guide channels.

29. The fingerprint detection device according to any one of claims 1 to 9, wherein each fingerprint detection unit further comprises:

a transparent dielectric layer disposed at least one of:

between the microlens array and the at least one light blocking layer,

between the at least one light-blocking layers, and

the at least one light blocking layer and the array of optically sensitive pixels.

30. The fingerprint detection device according to any one of claims 1 to 9 wherein said at least one light blocking layer is provided integrally with said microlens array or said at least one light blocking layer is provided integrally with said optically sensitive pixel array.

31. The fingerprint detection device according to any one of claims 1-9 wherein each microlens satisfies at least one of the following conditions:

the projection of the condensing surface of the micro lens on a plane perpendicular to the optical axis of the micro lens is rectangular or circular;

the condensing surface of the micro lens is an aspheric surface;

the curvatures of the converging surfaces of the microlenses in all directions are the same;

the microlens includes at least one lens; and

the focal length range of the micro lens is 10um-2mm.

32. The fingerprint detection device according to any one of claims 1 to 9 wherein said microlens array satisfies at least one of the following conditions:

the micro lens array is arranged in a polygonal shape; and

the duty cycle of the microlens array ranges from 100% to 50%.

33. The fingerprint detection device according to any one of claims 1 to 9 wherein the period of said microlens array is not equal to the period of said optically sensitive pixel array and the period of said microlens array is a rational multiple of the period of said optically sensitive pixel array.

34. The fingerprint detection device according to any one of claims 1-9, wherein a distance between the fingerprint detection device and the display screen is 20um-3000um.

35. The fingerprint detection device according to any one of claims 1 to 9, wherein each fingerprint detection unit further comprises:

a filter layer disposed at least one of:

above the microlens array, and

the microlens array is between the optical sensing pixel array.

36. An electronic device, comprising:

a display screen; and

A fingerprint detection device according to any one of claims 1 to 35.

37. The electronic device of claim 36, wherein the display screen includes a fingerprint detection area for providing a touch interface for a finger.