CN111461057A

CN111461057A - Under-screen biological characteristic detection system and electronic equipment

Info

Publication number: CN111461057A
Application number: CN202010294172.XA
Authority: CN
Inventors: 陈艺章; 张东虎
Original assignee: Shenzhen Fushi Technology Co Ltd
Current assignee: Shenzhen Fushi Technology Co Ltd
Priority date: 2020-04-15
Filing date: 2020-04-15
Publication date: 2020-07-28
Anticipated expiration: 2040-04-15
Also published as: CN111461057B

Abstract

The application provides a biological characteristic detecting system under a screen and an electronic device comprising the biological characteristic detecting system under the screen. The under-screen biometric detection system includes a passive light-emitting display device and a biometric detection device. The passive light-emitting display device comprises a display panel and a backlight module. The backlight module includes: the display panel comprises a light guide plate, a first light-gathering structure and a second light-gathering structure, wherein one side of the light guide plate facing the display panel is provided with the first light-gathering structure extending towards the display panel, the upper surface of the light guide plate comprises the surface of the first light-gathering structure, and the first light-gathering structure is used for gathering light rays emitted from the interior of the light guide plate to the upper surface of the light guide plate; and a second light condensing structure is arranged in an optical path from the lower surface of the light guide plate to the light sensing surface of the biological characteristic detection device, and the second light condensing structure is used for condensing the light emitted from the lower surface of the light guide plate.

Description

Under-screen biological characteristic detection system and electronic equipment

Technical Field

The embodiment of the application relates to the technical field of detection, and more particularly relates to a backlight module, a liquid crystal display device screen, a biological characteristic detection device, a screen-down biological characteristic detection system and an electronic device.

Background

A non-self-luminous display such as a liquid crystal display (L CD) screen comprises a backlight module for providing visible light and a display panel for realizing information display by using the visible light, a light source for providing active light is needed for realizing the biological characteristic detection under the screen based on the display, a detection light beam is emitted to an external object by using the light source, and then the detection light beam with the biological characteristic information of the external object is received and returned from the external object.

The light guide plate is a key structure in the backlight module, and a microstructure (or a V-cut structure) is formed on an upper surface of the light guide plate, and the microstructure is generally a prism structure distributed in a zigzag manner, as shown in fig. 1, and is used for guiding incident light from an edge direction to a viewing direction, increasing brightness of light, and making light uniform.

Since the detection light beam needs to pass through the backlight module in the display screen to reach the biological feature detection device under the screen after returning from the external object, the microstructure on the light guide plate in the backlight module affects the imaging effect of biological feature detection, the image splitting problem shown in fig. 1 occurs, and the accuracy of biological feature detection is affected.

Disclosure of Invention

The application provides a biological characteristic detecting system and electronic equipment under screen, can improve the degree of accuracy that biological characteristic detected under the screen.

In a first aspect, the present application provides a biological characteristic detecting system under screen, including luminous display device of passive form and biological characteristic detecting device, biological characteristic detecting device is used for setting up luminous display device below of passive form is in order to realize that biological characteristic detects under the screen, luminous display device of passive form includes display panel and backlight unit, backlight unit sets up display panel's below, display panel is used for the display screen, backlight unit is used for display panel realizes that the picture shows and provides visible light, backlight unit includes:

the display panel comprises a light guide plate and a light source, wherein the light guide plate comprises an upper surface and a lower surface which are oppositely arranged, the upper surface of the light guide plate is the surface of one side, facing the display panel, of the light guide plate, the lower surface of the light guide plate is the surface of one side, facing away from the display panel, of the light guide plate, the side, facing the display panel, of the light guide plate is provided with a first light condensation structure extending towards the display panel, the upper surface of the light guide plate comprises the surface of the first light condensation structure, and the first light condensation structure is used for condensing light rays emitted from the interior of the light guide plate to the; a second light condensing structure is arranged in an optical path from the lower surface of the light guide plate to the light sensing surface of the biological characteristic detection device, and the second light condensing structure is used for condensing light rays emitted from the lower surface of the light guide plate;

the biometric detection device includes:

and the image sensor is used for receiving the detection light beams returned from the external object above the passive light-emitting display device through the passive light-emitting display device, wherein the detection light beams returned from the external object are transmitted dispersedly after passing through the first light-focusing structure, the detection light beams transmitted dispersedly are converged after passing through the second light-focusing structure, and the detection light beams converged by the second light-focusing structure are used for the biological characteristic detection device to acquire the biological characteristic information of the external object.

In some optional implementations, the first light concentrating structure and the second light concentrating structure are both prism structures and are disposed opposite to each other; or

The first light gathering structure and the second light gathering structure are both arc-shaped protruding structures and are arranged in a back-to-back mode.

In some optional implementations, the first light-collecting structure includes a plurality of first prisms arranged in parallel, and the second light-collecting structure includes a plurality of second prisms arranged in parallel, where the plurality of first prisms and the plurality of second prisms are arranged opposite to each other and opposite to each other; or

The first light-gathering structure comprises a plurality of first prisms which are arranged in parallel, the second light-gathering structure comprises a single third prism, and the plurality of first prisms and the third prism are arranged in an opposite mode; or

The first light gathering structure comprises a plurality of first arc-shaped protruding structures which are arranged in parallel, the second light gathering structure comprises a plurality of second arc-shaped protruding structures which are arranged in parallel, and the plurality of first arc-shaped protruding structures and the plurality of second arc-shaped protruding structures are arranged opposite to each other one by one and are opposite to each other; or

The first light gathering structure comprises a plurality of first arc-shaped protruding structures which are arranged in parallel, the second light gathering structure comprises a single third arc-shaped protruding structure, and the plurality of first arc-shaped protruding structures and the third arc-shaped protruding structures are arranged in a back-to-back mode.

In some optional implementations, the first prism and the second prism disposed opposite to each other are the same prism; or

The first prism and the third prism are similar in shape, and the third prism is larger in size than the first prism.

In some alternative implementations, the third prisms are sized such that light exiting the lower surface of the light guide plate within the field of view of the biometric detection device is each focused.

In some optional implementation manners, the plurality of parallel first arc-shaped protruding structures are a plurality of first lenses, the plurality of parallel second arc-shaped protruding structures are a plurality of second lenses, focal points of the first lenses and focal points of the second lenses, which are arranged opposite to each other, coincide, and a ratio of diameters of the first lenses and the second lenses is a ratio of focal lengths of the first lenses and the second lenses.

In some alternative implementations, the plurality of first prisms are triangular prisms, the third prisms are also triangular prisms, and the first prisms and the third prisms have equal apex angles and opposite orientations.

In some optional implementations, the backlight module further includes:

and the reflecting sheet is arranged below the lower surface of the light guide plate, and the second light condensing structure is arranged on the lower surface of the reflecting sheet.

In some optional implementations, the second light-condensing structure is disposed on the whole area of the lower surface of the reflective sheet, or on a partial area of the lower surface of the reflective sheet, where the partial area is an area where the field of view of the biometric detection apparatus is directly opposite to the lower surface of the reflective sheet.

In some optional implementations, the backlight module further includes:

the metal reinforcing plate is arranged below the reflector plate, an opening is formed in the metal reinforcing plate, the biological characteristic detection device is arranged below the opening, and the second light condensation structure is arranged below the opening area.

In some alternative implementations, the second light concentrating structure has a size larger than the size of the opening.

In some optional implementations, the second light concentrating structure is disposed at a localized area of the lower surface of the light guide plate; or a local part of one side of the light guide plate, which is opposite to the display panel, extends out of the second light concentrating structure, and the lower surface of the light guide plate comprises the lower surface of the second light concentrating structure; the local area is an area where the view field of the biological feature detection device is over against the lower surface of the light guide plate.

In some optional implementations, a lower surface of the light guide plate is provided with a dot structure, and the local area of the lower surface of the light guide plate is not provided with the dot structure.

In some optional implementations, the distribution of the mesh points of the surrounding area of the local area is configured such that the display screen brightness of the local area and the display screen brightness of the surrounding area are comparable to make the brightness of the display screen uniform.

In some alternative implementations, the second light concentrating structure is disposed on a light-sensing surface of the biometric detection device.

In some optional implementation manners, the light guide plate further includes a light incident surface located between the upper surface and the lower surface, and the backlight module further includes:

the backlight source is arranged on one side of the light incident surface of the light guide plate, wherein visible light emitted by the backlight source enters the light guide plate through the light incident surface and is emitted from the upper surface of the light guide plate, and the arrangement direction of the first light gathering structures is parallel to the light incident surface.

In some optional implementations, when the second light concentrating structure is multiple, both the first light concentrating structure and the second light concentrating structure are elongated structures.

In some optional implementations, the biometric detection device further includes:

the detection light source is used for providing a detection light beam required by the detection of the biological characteristic information;

the detection light beam emitted by the detection light source returns from an external object above the passive light-emitting display device, then enters the backlight module after passing through the panel display panel, is converged by the first light-condensing structure in the backlight module, then is transmitted in a dispersed manner, is further converged by the second light-condensing structure, and finally enters the light-sensing surface of the image sensor.

In some optional implementations, the detection light source is an infrared light source, and the detection light beam is near-infrared light.

and the optical filter is arranged between the backlight module and the photosensitive surface of the image sensor and used for filtering optical signals of wave bands which are not used for biological characteristic detection.

In some alternative implementations, the biometric detection device is a fingerprint detection device for detecting fingerprint information from an external object above the passively illuminated display device.

In a second aspect, the present application further provides an electronic device, including: the system for detecting the underscreen biometric characteristic according to any one of the implementation manners of the first aspect.

Based on the technical scheme, the first light condensation structure can condense the light emitted from the inside of the light guide plate to the upper surface of the light guide plate, and the condensed light is further dispersed and transmitted to realize the light guide effect of the light guide plate. For the detection beam returned from the external object, the first light condensing structure may perform a light-splitting process on the detection beam returned from the external object. Further, a second light condensing structure is arranged between the lower surface of the light guide plate and a light sensing surface of the biological characteristic detection device, light rays which are subjected to light splitting processing through the first light condensing structure are continuously transmitted downwards to the second light condensing structure, the light rays which are subjected to light splitting processing are subjected to light combining processing through the second light condensing structure, detection light beams after light combining are obtained, biological characteristic information detection is carried out based on the detection light beams, the image splitting problem of images can be avoided, and the accuracy of biological characteristic detection is improved.

Drawings

Fig. 1 is a schematic structural view of a light guide plate.

Fig. 2 is a schematic plan view of an electronic device to which the present application may be applied.

FIG. 3 is a schematic partial cross-sectional view of one embodiment of the electronic device shown in FIG. 2.

Fig. 4 is a schematic diagram of an exemplary structure of a backlight module.

FIG. 5 is a schematic diagram of a microstructure of a light guide plate.

Fig. 6 is a schematic structural diagram of a backlight module according to an embodiment of the present application.

Fig. 7 to 8 are schematic views of typical structures of the second light-condensing structure.

FIG. 9 is a schematic view of another microstructure of a light guide plate.

Fig. 10 is a schematic diagram of an optical path of a portion of the microstructure of the light guide plate shown in fig. 9.

Fig. 11 to 13 are schematic views of typical arrangements of the second light-concentrating structure.

Fig. 14 is a schematic structural view of an L CD screen of an embodiment of the present application.

Fig. 15 is a schematic configuration diagram of a biometric detection apparatus according to an embodiment of the present application.

Fig. 16 is a schematic structural diagram of an electronic device according to an embodiment of the present application.

Detailed Description

In the detailed description of the embodiments herein, it will be understood that when a substrate, a sheet, a layer, or a pattern is referred to as being "on" or "under" another substrate, another sheet, another layer, or another pattern, it can be "directly" or "indirectly" on the other substrate, the other sheet, the other layer, or the other pattern, or one or more intervening layers may also be present. The thickness and size of each layer in the drawings of the specification may be exaggerated, omitted, or schematically represented for clarity. Further, the sizes of the elements in the drawings do not completely reflect actual sizes.

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures. Further, the described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

In the following description, numerous specific details are provided to provide a thorough understanding of embodiments of the application. One skilled in the relevant art will recognize, however, that the technology can be practiced without one or more of the specific details, or with other structures, components, etc.

Before describing the technical solution of the embodiment of the present application, first, a brief description is made of an electronic device to which the present application is applied with reference to fig. 2 and 3.

Fig. 2 is a perspective view of an electronic device 100 to which the present application is applied, and fig. 3 is a partial sectional view of the electronic device 100 shown in fig. 2 along a direction a-a.

It should be understood that the electronic device 100 of the present embodiment may include, but is not limited to, a smart phone, a tablet, a computer, a notebook, a smart wearable device, a smart door lock, and the like. In order to realize the basic functions of the electronic device 100, the electronic device 100 in the embodiment of the present application may include other necessary modules or components in addition to the modules or components illustrated below. Taking the electronic device as a smart phone as an example, it may further include a communication module, a speaker, a microphone, a battery, and the like.

For convenience of distinction and illustration, a direction in which the display of the electronic apparatus 100 points or faces the user in the normal use state of the electronic apparatus 100 is defined as "up", and a direction opposite thereto, or a direction away from the user is defined as "down". The electronic device 100 has a length direction, a width direction, and a thickness direction perpendicular to each other, as shown in fig. 2 and 3, which are respectively represented by a Y-axis, an X-axis, and a Z-axis. It should be understood that the definitions of the directions in the embodiments of the present application are only for convenience of description and are not used as limitations of the embodiments of the present application.

In some embodiments, as shown in fig. 3, the electronic device 100 may include a display module 12 and a detection module 19, the detection module 19 is disposed below the display module 12, and the display module 12 has a detection area VA for an external object 1000 to contact. When the external object 1000 contacts the detection area VA, the detection module 19 may acquire a biometric image of the external object 1000 and obtain corresponding biometric information. The external object 1000 may be, for example, a finger, and correspondingly, the detection module 19 may collect a fingerprint image of the finger to obtain corresponding fingerprint feature information.

Optionally, in some embodiments, as shown in fig. 3, the electronic device 100 may further include a protective layer 11 disposed above the display module 12 and covering the front surface of the electronic device 100. That is, the upper surface (not numbered) of the protective layer 11 may be the outermost surface of the electronic device 100. In this case, the sensing area VA is at least a partial area of the upper surface of the protective layer 11. For example, the detection area VA may be any partial area of the upper surface of the protection layer 11, or may be the entire area of the upper surface of the protection layer 11. In one embodiment, the A-A line of the electronic device 100 is parallel to the Y-axis and intersects the detection area VA. More specifically, the line a-a of the electronic device 100 may be a straight line parallel to the Y-axis passing through the center point of the detection area VA.

It should be understood that the protective layer 11 may include a plastic film, a toughened film, or other films that are attached by a user during actual use, and the upper surface of the protective layer 11 is a surface that the external object 1000 directly contacts when performing biometric detection. The upper surface of the protective layer 11 is the outermost surface of the electronic device 100. Here, for example, but not limiting of, the external object 1000 may be a finger and the biometric characteristic may be a fingerprint. In other or alternative embodiments, the biometric characteristic may be, but is not limited to, a fingerprint, a toe print, a palm print, a skin print, a blood vessel, and the like.

In some embodiments, the display module 12 may be a self-luminous display module having self-luminous display units, for example, the display module 12 may be an O L ED display module, or a Micro light emitting diode (Micro-L ED) display module, and the self-luminous display units in the display module 12 may provide detection light beams for detecting biological characteristics, for example, a part of the self-luminous units in the display module 12 may be used as a detection light source for detecting biological characteristics.

In other embodiments, the display module 12 may be a passive light emitting display module, for example, an L CD display module, which may include a liquid crystal display panel (not shown in fig. 3) and a backlight unit (not shown in fig. 3), where the backlight unit is configured to provide visible light to a side where the liquid crystal display panel is located, and the visible light can reach eyes of a user after passing through the liquid crystal display panel and the protective layer 11, so as to realize information display, including but not limited to text display, image display, and the like.

In some embodiments, the liquid crystal display panel may include a multi-layer structure of a cf (color filter) substrate, a liquid crystal layer, a tft (thin Film transistor) substrate, and a polarizer. The backlight unit may include a multi-layer structure of a reflective sheet, a light guide plate, a diffusion sheet, a brightness enhancement sheet, etc.

Further, as shown in fig. 3, the electronic device 100 further includes a detection light source 16, which may provide a detection light beam 101, wherein the detection light beam 101 can penetrate through the protection layer 11 to reach the external object 1000. The detection beam 101 is reflected on the external object 1000 or the detection beam 101 is transmitted after entering the inside of the external object 1000, thereby carrying the biometric information of the external object 1000. The detection light beam 101 carrying the biological characteristic information of the external object 1000 can penetrate through the protective layer 11 and the display module 12 and then be received by the detection module 19, and is used for generating a biological characteristic image of the external object 1000.

In some embodiments, the protective layer 11 includes a non-transparent portion 112 and a transparent portion 114, and the non-transparent portion 112 is located at a periphery or edge of the transparent portion 114. The non-transparent portion 112 is capable of blocking visible light, and the transparent portion 114 is capable of transmitting visible light. The surface of the side of the protection layer 11 opposite to the display module 12 (i.e. the upper surface of the protection layer 11) has the detection area VA, which is a local area of the upper surface of the protection layer 11. Optionally, part or all of the detection area VA is located in the transparent portion 114. The display module 12 can transmit visible light from the transparent portion 114 of the protection layer 11 to display information.

The detection light source 16 is located below the opaque portion 112. The detection light source 16 is capable of providing a detection light beam 101 above the protective layer 11. The wavelength of the detection beam 101 is different from the wavelength of visible light. The wavelength of the detection beam 101 may be different from the visible light. The detection beam 101 may be non-visible light. For example, but not limiting of, the detection beam 101 may be near infrared light having a wavelength in the range of 780 nanometers to 2000 nanometers. Further, the wavelength of the detection beam 101 may be 850 nanometers or 940 nanometers. Both the opaque portion 112 and the transparent portion 114 can transmit the detection beam 101.

Optionally, the electronic device 100 further comprises a middle frame 13, wherein the middle frame 13 comprises a bottom portion 131 and a side portion 132, and the display device 12 is disposed between the middle frame 13 and the protective layer 11. The bottom 131 of the middle frame is provided with a through hole 1311, and the detection module 19 receives a detection beam returned by the external object 1000 through the through hole 1311, for example. The side portion 131 is located at a side of the display module 132 and faces the non-transparent portion 112. The detection light source 16 is disposed on the side portion 132, for example, but not limited to.

Alternatively, the through hole 1311 may not be formed in the bottom 131 of the middle frame, and the detection module 19 may be disposed on a surface of the bottom 131 facing the display module 12.

Optionally, in some embodiments, the detection light source 16 includes a light emitting unit 161 for emitting a detection light beam. Further optionally, the detection light source 16 further includes a conversion unit 162. The conversion unit 162 is disposed on the light emitting unit 161, for example, and is used for converting the emitting angle of the detection light beam emitted by the light emitting unit 161.

However, alternatively, in some other embodiments, the detection light source 16 may also be disposed below the display module 12, or integrated in a backlight light source of a backlight unit, and so on.

Alternatively, in some embodiments, the protective layer 11 may be a single layer structure, or a multi-layer structure. The protective layer 11 is a substantially thin plate having a predetermined length, width and thickness. The protective layer 11 has a longitudinal direction corresponding to the Y axis, a width direction corresponding to the X axis, and a thickness direction corresponding to the Z axis. The protective layer 11 may include a transparent substrate (not shown) capable of transmitting visible light and the detection beam 101, and an optical ink layer (not shown) capable of blocking visible light and transmitting the detection beam 101. The optical ink layer may be disposed on the lower surface of the protective layer 11 near the edge, so that the protective layer 11 forms the opaque portion 112 and the transparent portion 114. Alternatively, the transparent substrate is, for example, but not limited to, glass, plastic, resin, or any other transparent material. The optical ink layer is, for example but not limited to, an infrared ink capable of transmitting near infrared light and blocking visible light, in this case, the detection module 19 may use near infrared light as the detection beam 101 to achieve the biometric detection of the external object 1000.

When the display module 12 is an L CD display module, the working principle of the backlight unit in the L CD display module is described with reference to fig. 4.

As a typical structure, as shown in fig. 4, the backlight unit includes, in order from an upper layer to a lower layer: an incremental sheet 115, a diffusion sheet 116, a light guide plate 117, a backlight source 17, and a reflection sheet 118.

The reflective sheet 118 is configured to totally reflect the visible light emitted from the lower surface of the light guide plate 117 directly above the display panel, the light guide plate 117 is configured to guide the visible light emitted from the backlight source 17 to the whole display panel, the diffusion sheet 116 is configured to diffuse the visible light signal transmitted through the light guide plate 117 and transmit the diffused visible light signal to the brightness enhancement sheet 112, and the brightness enhancement sheet 112 is configured to modify a light exit angle of the received visible light signal to increase the intensity of the visible light signal emitted from the front surface of the display panel.

In order to realize the light guiding function of the light guide plate 117, two layers of microstructures are usually formed on the light guide plate 117, as shown in fig. 5, a light gathering microstructure (V-cut structure) 1172 is formed on one side of the light guide plate 117 facing the display panel, and a dot microstructure 1171 is formed on one side of the light guide plate 117 facing away from the display panel. In a specific implementation, the backlight source 17 may be disposed on one side of the side surface of the light guide plate 117, the visible light emitted from the backlight source enters the light guide plate 117, when the visible light enters the dot microstructures 1171 on the lower surface, the reflected light is diffused at various angles, and then is converged by the light converging microstructures 1172 on the upper surface of the light guide plate 117 and emitted, and the visible light signal emitted from the upper surface of the light guide plate 117 matches with other structures in the backlight unit to realize front emission of the display panel. However, in practical applications, the detection beam 101 returning from the external object 1000 passes through the protection layer 11 and the display module 12 in sequence and reaches the detection module 19. That is, the detection beam 101 is also transmitted in the backlight unit of the display module 12, thus, the transmission of the detection beam 101 is affected by the microstructure of the light guide plate, as shown in FIG. 1, because the light guide plate is provided with the V-cut structure, the detection light beam incident from the upper part of the V-cut structure can be converged after passing through the V-cut structure, the converged detection light beam is further dispersed and transmitted, and the detection light beam is equivalent to a plurality of detection light beams returned from a certain point on the external object 1000, and then further dispersed and transmitted to form a plurality of dispersed detection light beams, then a similar problem of image splitting as shown in fig. 1 occurs when imaging on the detection module 19 based on the plurality of dispersed detection beams, which affects the accuracy of the biometric detection, and the V-cut structure can disperse the detection beam to the lower part of the screen, so that the signal loss is caused, and the imaging effect is influenced.

In view of this, the embodiments of the present application provide a solution, in which a second light converging structure is added in a light path between a light guide plate and a detection module, so that a signal dispersedly transmitted after being converged by a microstructure of the light guide plate can be converged before entering the detection module, thereby reducing or eliminating an influence of the microstructure in the light guide plate on biological feature detection, and further improving accuracy of the biological feature detection.

It should be understood that the detection module of the embodiment of the present application may also be referred to as a biometric detection module, a biometric detection device, a biometric sensing device, and the like, which may be used to collect biometric information of an external object, for example, fingerprint information, palm print information, 3D face information, and the like.

Hereinafter, a backlight module according to an embodiment of the present application will be described with reference to fig. 6 to 13.

It should be understood that the backlight module in the embodiment of the present application is a backlight module in a display module, such as an L CD display module, and the display module may further include a display panel, the backlight module is disposed below the display panel, the display panel is used for displaying pictures, and the backlight module is used for providing visible light for the display panel to realize picture display.

As shown in fig. 6, the lower portion of the backlight module 20 is used for disposing the biometric feature detection device 30 to achieve the under-screen biometric feature information detection, wherein the backlight module 20 includes:

the light guide plate 200 comprises an upper surface 201 and a lower surface 202 which are opposite to each other, wherein the upper surface 201 of the light guide plate 200 is a surface of one side of the light guide plate 200 facing the display panel, the lower surface 202 of the light guide plate 200 is a surface of one side of the light guide plate 200 facing away from the display panel, one side of the light guide plate 200 facing the display panel is provided with a first light condensing structure 210 extending towards the display panel, the upper surface 201 of the light guide plate 200 comprises a surface of the first light condensing structure 210, and the first light condensing structure 210 is used for condensing light rays which are emitted from the inside of the light guide plate 200 to the upper surface 201 of the light guide plate;

wherein, a second light focusing structure 40 is disposed in the light path from the lower surface of the light guide plate 200 to the light sensing surface of the biometric sensing device 30, and the second light focusing structure 40 is used for focusing the sensing light emitted from the lower surface 202 of the light guide plate 200.

Alternatively, a side of the light guide plate 200 facing away from the display panel has a second light concentrating structure 40 extending in a direction away from the display panel (opposite to the Z-axis direction), and the lower surface 202 of the light guide plate 200 includes a surface of the second light concentrating structure 40. Optionally, a partial region of one side of the light guide plate 200 facing away from the display panel extends out of the second light concentrating structure 40.

Here, the first light-focusing structure 210 may correspond to the light-focusing microstructure 1172 in fig. 5, and the biometric detection apparatus 30 may correspond to the detection module 19 in fig. 3, and the related implementation thereof can refer to the related description of the foregoing embodiments, and for brevity, the description thereof is omitted here.

It should be understood that, in the embodiment of the present application, the first light-gathering structure 210 is a structure in the light guide plate 200, that is, the first light-gathering structure 210 belongs to the light guide plate 200, and may be matched with other structures in the backlight module 20 to implement the display function of the display panel, and the present application is not limited to the formation manner of the first light-gathering structure 210, for example, in one implementation, the first light-gathering structure 210 is prepared on a substrate of the light guide plate 200, or in other alternative implementations, the first light-gathering structure 210 and other structures in the light guide plate 200 are an integral structure formed by the same material.

In a specific optical path, the first light-gathering structure 210 may gather light emitted from the inside of the light guide plate 200 to the upper surface 201 of the light guide plate 200, and the gathered light is further dispersed and transmitted so as to achieve a light-guiding effect of the light guide plate 200. For the detection light beam 501 returning from the external object 1000, the first light-condensing structure 210 may perform a converging process on the detection light beam 501, the converged detection light beam is further dispersed and transmitted to form a detection light beam 511, and imaging is performed based on the detection light beam 511, so that the image splitting problem in fig. 1 may occur.

Further, the detection light beam 511 transmitted dispersedly continues to be transmitted downward to the second light focusing structure 40, the second light focusing structure 40 performs convergence processing on the detection light beam 511 transmitted dispersedly to obtain the converged detection light beam 502, the biometric feature detection apparatus 30 receives the detection light beam 502 and performs biometric feature detection based on the detection light beam 502, so that the problem of image splitting during imaging can be avoided, and the accuracy of biometric feature detection can be improved.

It should be understood that the shape, size, arrangement, and the like of the first light collecting structure 210 are not particularly limited in the present application, as long as the first light collecting structure can cooperate with other structures in the backlight module 20 to achieve the display purpose of the display module. The specific structures of the first light concentrating structure 210 and the second light concentrating structure 40 in fig. 6 are only examples, and should not limit the present application in any way.

As an embodiment, the first light-focusing structure 210 is a prism structure, for example, as shown in fig. 8, the first light-focusing structure 210 may include a plurality of first prisms 211 arranged in parallel, or the first light-focusing structure 210 may include a plurality of first prisms arranged in other manners.

As another embodiment, the first light-gathering structure 210 may also be an arc-shaped protrusion structure, for example, as shown in fig. 7, the first light-gathering structure 210 includes a plurality of first arc-shaped protrusions arranged side by side, or may also include a plurality of first arc-shaped protrusions arranged in other manners.

When the first light-gathering structure 210 is a prism structure, the second light-gathering structure 40 may also be designed as a prism structure, and may be designed as a prism structure disposed opposite to the first light-gathering structure 210.

As an example, as shown in fig. 8, the first light-gathering structure 210 includes a plurality of first prisms 211 arranged in parallel, the second light-gathering structure 40 includes a plurality of second prisms 42 arranged in parallel, and the plurality of second prisms 42 and the plurality of first prisms 211 are directly opposite to each other.

The second prisms 42 and the opposite first prisms 211 in the second light-focusing structure 40 are prisms with the same shape and size, and the second prisms 42 and the opposite first prisms 211 are arranged opposite to each other and aligned with each other. In this way, after the detection light beam 501 is converged by the first prism 211 in the first light-converging structure, the converged detection light beam is further dispersed and transmitted to form the detection light beam 511 and transmitted to the second light-converging structure 40, and then converged by the second prism 422 in the second light-converging structure 40 to form the detection light beam 502 and transmitted to the biometric feature detection apparatus 30, and further, the biometric feature detection apparatus 30 can be favorable for eliminating the image splitting problem during imaging based on the biometric feature of the detection light beam 502.

It should be understood that the plurality of first prisms 211 may be the same prisms, or may also be different prisms, which is not limited in the embodiments of the present application.

When the first prisms 211 are the same prisms, the second prisms 42 may also be the same prisms, and the first prisms 211 and the second prisms 42 are arranged opposite to each other and aligned with each other.

When the plurality of first prisms 211 are different prisms, the plurality of second prisms 42 may also be different prisms, but the second prisms 42 and the opposite first prisms 211 are the same prisms, and the first prisms 211 and the opposite second prisms 42 are located on the same optical path of the detection light beam, so that the detection light beam converged and dispersedly transmitted by the first prisms 211 can be converged by the opposite second prisms 42, thereby achieving the purpose of eliminating the image splitting problem.

As another example, as shown in fig. 9, the first light-gathering structure 210 includes a plurality of first prisms 211 arranged side by side, the second light-gathering structure 40 includes a single third prism 43, the third prism 43 and the first prism 211 are prisms having the same shape but different sizes (i.e., they are similar), and the third prism 43 and the plurality of first prisms 211 are disposed opposite to each other. In this case, the third prism 43 does not need to be disposed in alignment with the first prism 211. After the detection light beams 501 returned from the external object 1000 are converged by the plurality of first prisms 211 in the first light converging structure 210, the converged detection light beams are further dispersed and transmitted to form detection light beams 511, and after the detection light beams are transmitted to the second light converging structure 40, the detection light beams 502 are further converged by the third prism 43 in the second light converging structure 40 to form detection light beams 502, and the detection light beams 502 are transmitted to the biometric detection device 30, and further, the biometric detection device 30 performs biometric detection based on the detection light beams 502, which is beneficial to eliminating the image splitting problem during imaging.

As a specific implementation manner, the first prism 211 is a triangular prism, the second prism 42 or the third prism 43 is also a triangular prism, and the vertex angle of the triangular prism in the first light-gathering structure 210 is the same as the vertex angle of the triangular prism in the second light-gathering structure 40, and the directions are opposite.

Alternatively, in some embodiments, as shown in fig. 9, the first light concentrating structure 210 is an arc-shaped convex structure. Referring to fig. 6, the second light-gathering structure 40 may also be designed as a facing arc-shaped protrusion structure, and may be designed as an arc-shaped protrusion structure disposed opposite to the first light-gathering structure 210.

As an embodiment, the first light-gathering structure 210 includes a plurality of first arc-shaped protrusion structures arranged in parallel, in this case, as an implementation manner, the second light-gathering structure 40 may include a plurality of second arc-shaped protrusion structures arranged in parallel, wherein the plurality of first arc-shaped protrusion structures and the plurality of second arc-shaped protrusion structures are directly opposite to each other, and each second arc-shaped protrusion structure and the directly opposite first arc-shaped protrusion structure are arranged in a reverse manner; as another implementation manner, the second light concentrating structure 40 includes a single third arc-shaped protruding structure, wherein the plurality of first arc-shaped protruding structures and the third arc-shaped protruding structures are disposed opposite to each other.

For example, as shown in fig. 10, the plurality of first arc-shaped protrusion structures arranged in parallel may be a plurality of first lenses 2111, and the plurality of second arc-shaped protrusion structures arranged in parallel may be a plurality of second lenses 412, wherein the second lenses 412 are disposed below the opposite first lenses 2111, the focal points f of the first lenses 2111 and the opposite second lenses 412 are coincident, and the ratio between the diameter D1 of the first lenses 2111 and the diameter D2 of the second lenses 412 is the ratio between the focal length f1 of the first lenses 2111 and the focal length f2 of the second lenses 412. Optionally, the diameter D2 of the second lens 412 is smaller than the diameter D1 of the first lens 2111.

Accordingly, after the detection light beam 501 returned from the external object 100 enters the backlight module 20, the detection light beam 511 is converged by the first lens 2111 in the light guide plate 200 of the backlight module 20 to form the detection light beam 511, the detection light beam 511 is further transmitted to the corresponding second lens 412, and the detection light beam 502 is converged by the second lens 412, so that, based on the above arrangement, the detection light beam incident from above the light guide plate 200 can be converged to the photosensitive surface of the biometric detection apparatus 30 to the maximum extent after being transmitted by the first lens 2111 and the second lens 412, which is beneficial to ensuring the lossless or nearly lossless transmission of the detection light beam, and improving the imaging quality of biometric detection.

Optionally, in some embodiments, the plurality of second lenses 412 are disposed in a partial region of the lower surface 202 of the light guide plate 200, or a partial region of a side of the light guide plate 200 facing away from the display panel extends out of the plurality of second lenses 412. The local area is a detection area where the field of view of the biometric detection device 30 is directly opposite to the lower surface 202 of the light guide plate 200. The lower surface 202 of the light guide plate 200 includes surfaces of the plurality of second lenses 412. In this way, the propagation direction of the detection beam vertically downward (in the direction opposite to the Z-axis direction) incident on the surface of the first lens 2111 after passing through the second lens 412 can be substantially unchanged, and thus the accuracy of biometric sensing can be improved.

As a specific implementation manner, the size and arrangement manner of the dot structure in the local area on the lower surface of the light guide plate 200 may be modified according to the size and arrangement manner of the plurality of second lenses 412, so that lossless or near lossless transmission of the detection light beam passing through the local area on the light guide plate 200 can be realized through the processing of the light path by the plurality of first lenses 2111 and the plurality of second lenses 412 in the local area.

In summary of the optical path transmission of the detection beam in the foregoing embodiment, the first light converging structure 210 can converge the detection beam 501 (assuming that the detection beam 501 is two beams from the same point on an external object, and the external object is far away from the imaging plane, and the two beams can be considered as parallel beams approximately) transmitted along a specific direction (e.g. a direction perpendicular to the display panel or a direction opposite to the Z-axis direction), and then the converged detection beam is converted into the detection beam 511 dispersedly transmitted along another direction (e.g. a direction inclined with respect to the display panel), and then imaging based on the dispersedly transmitted detection beam 511 forms images of a plurality of external objects, which leads to the aforementioned image splitting problem. In the embodiment of the present application, the detection light beam 511 that is dispersedly transmitted can be converged by disposing the second light-focusing structure 40 in the light path before entering the biometric detection apparatus 30, and it can be understood that the detection light beam 511 that is dispersedly transmitted after passing through the second light-focusing structure 40 is converted to be transmitted along the original direction (i.e. the transmission direction of the detection light beam 501), that is, the image splitting problem in imaging caused by the microstructure of the light guide plate 200 can be eliminated compared with the elimination of the influence of the first light-focusing structure 210 on the light path transmission of the detection light beam.

Optionally, in some embodiments, the plurality of second light concentrating structures 40 are disposed opposite to the plurality of first light concentrating structures 210, so that when the first light concentrating structures 210 convert the light signals incident to the first light concentrating structures 210 in the first direction into light signals in at least one second direction, the second light concentrating structures 40 are configured to convert the light signals in the at least one second direction transmitted through the first light concentrating structures 210 into light signals in the first direction again and transmit the light signals to the biometric detection apparatus 30. Thus, the problem of the occurrence of image splitting after the detection light beam passes through the first light-condensing structure 210 on the light guide plate 200 can be solved. It should be understood that, in the embodiment of the present application, the second light focusing structure 40 may be fixed at any position from the lower surface of the light guide plate 200 to the light sensing surface of the biometric feature detection apparatus 30, for example, the second light focusing structure 40 may be fixed by an existing structure, or the second light focusing structure 40 may be fixed by an additional structure, such as an additional bracket, a supporting plate, or the like. Alternatively, a second light concentrating structure 40 extends from a local region of the light guide plate 200 on a side opposite to the display panel, that is, the second light concentrating structure 40 is a part of the light guide plate 200 itself.

In some embodiments of the present application, as shown in fig. 11 to 13, the backlight module 20 further includes:

and a reflective sheet 300, wherein the reflective sheet 300 is disposed below the lower surface of the light guide plate 200, and the reflective sheet 300 is used for reflecting the light emitted from the lower surface of the light guide plate 200 back into the light guide plate 300, so as to improve the utilization efficiency of the light.

Further, in other embodiments of the present application, as shown in fig. 11 to 13, the backlight module 20 may further include:

the metal reinforcing plate 400 is disposed below the reflection sheet 300, an opening is disposed in the metal reinforcing plate 400, and the biometric detection device 30 is disposed below the opening and is configured to receive a detection beam returned from an external object and transmitted through the opening to obtain biometric information of the external object.

Hereinafter, referring to fig. 11 to 13, taking the first light-gathering structure 210 and the second light-gathering structure 40 as prism structures as an example, a specific arrangement manner of the second light-gathering structure 40 is described, and in other cases, the arrangement manner of the second light-gathering structure 40 is similar, and is not repeated here for brevity.

As an arrangement, as shown in fig. 11, the second light condensing structure 40 is disposed on the lower surface of the reflective sheet 300.

Since the lower surface of the reflective sheet 300 is a smooth plane, and the second light-focusing structure 40 is disposed on the lower surface of the reflective sheet 300, the first light-focusing structure 210 and the second light-focusing structure 40 can be aligned relatively accurately, and further the second light-focusing structure 40 can perform relatively accurate focusing processing on the detection light beams which are transmitted dispersedly.

Moreover, the adoption of the setting mode can be realized without modifying other structures in the backlight module, and the influence on the display function of the display screen can be reduced.

As a specific implementation, the second light focusing structure 40 may be adhered to the lower surface of the reflective sheet 300, for example, the second light focusing structure 40 may be adhered to the lower surface of the reflective sheet 300 by an optical adhesive, or the second light focusing structure 40 may be fixed to the lower surface of the reflective sheet 300 in other manners.

In some embodiments, the second light concentrating structure 40 is disposed on the entire lower surface of the reflective sheet 300.

In other embodiments, the second light focusing structure 40 is at least disposed in a partial area of the lower surface of the reflective sheet 300, where the partial area is an area where the field of view of the biometric detection apparatus 30 is directly opposite to the lower surface of the reflective sheet 300, that is, the second light focusing structure 40 only needs to combine the detection light beams within the field of view, and the detection light beams outside the field of view cannot be received by the biometric detection apparatus 30, so that the detection light beams may not be processed.

It should be noted that the field of view of the biometric detection device 30 corresponds to a corresponding region in each layer of the backlight module 20, and the field of view of the biometric detection device 30 sequentially decreases from top to bottom in each layer of the structure, as shown in fig. 13, the region where the field of view of the biometric detection device 30 is directly opposite to the lower surface of the light guide plate 200 is a region S1.

As another arrangement, as shown in fig. 12, the second light condensing structure 40 is disposed below the opening region of the metal reinforcing plate 400.

In some implementations, the second light concentrating structure 40 may be fixed to the lower surface of the open area, or may be fixed below the open area by other structures, such as a bracket.

Take the second light concentrating structure 40 as an example of a single triangular prism, the single triangular prism may be fixed to the lower surface of the opening region of the metal reinforcing plate 400, the size of the one surface of the metal reinforcing plate 400 close to the single triangular prism is larger than the size of the opening so that the triangular prism can be fixed to the lower surface of the opening region, for example, the triangular prism may be fixed to the lower surface of the metal reinforcing plate by a double-sided adhesive tape, or in other manners.

In a specific implementation, the size of the single triangular prism is configured to make the lights emitted from the lower surface of the light guide plate 200 within the range of the field of view of the biometric detection apparatus 30 all be converged, so that the detection light beams returning from the external object within the range of the field of view can all be synthesized and further transmitted to the biometric detection apparatus 30, and the imaging quality of biometric detection can be improved.

As another way of providing the image display device, as shown in fig. 13, the second light-focusing structure 40 is at least disposed in a partial region S1 on a side of the light guide plate 200 opposite to the display panel, and the partial region S1 is a region where the field of view of the biometric detection device 30 is directly opposite to the lower surface of the light guide plate. The second light concentrating structure 40 is, for example, a structure extending from a partial region S1 on a side of the light guide plate 200 opposite to the display panel, or the second light concentrating structure 40 is disposed on a lower surface of the light guide plate 200.

As shown in fig. 13, the lower surface of the light guide plate 200 is formed with a dot structure 220, and a partial region S1 in the light guide plate 200 may be modified to provide the second light concentrating structure 40 in the partial region S1. In some implementations, the partial region S1 of the lower surface of the light guide plate 200 is not provided with the dot structure. Or in other implementations, the dot structures, etc. may be disposed in the gaps of the second light concentrating structure 40.

The dot structure 220 may correspond to the dot microstructure 1171 in fig. 5, which is used to diffuse the light incident on the lower surface of the light guide plate 200 to various angles to achieve uniform light emission on the front surface of the display panel, and when the second light condensing structure is disposed on the lower surface of the light guide plate 200, the front surface light emission of the display panel may be affected, so that further, the distribution of the dots in the surrounding area of the local area S1 may be adjusted, so that the brightness of the display panel in the local area is equivalent to that in the surrounding area, so that the brightness of the display screen is uniform.

For example, if the brightness of the display panel in the local area is reduced after the second light-focusing structure 40 is disposed in the local area S1, in this case, the distribution of the dots in the surrounding area of the local area may be set to be denser, or the diffusion angle of the dots in the surrounding area to the light rays may be adjusted, so as to improve the brightness of the display panel corresponding to the local area.

As another arrangement, the second condensing structure 40 is disposed on the photosensitive surface of the biometric detection apparatus 30.

In some embodiments, the second light concentrating structure 40 may be disposed on the light-sensitive surface of the biometric device 30 by an optical glue or a fixed mount, or the like.

Optionally, in some embodiments of the present application, the light guide plate 200 further includes a light incident surface located between the upper surface and the lower surface of the light guide plate 200, or located at a side edge of the light guide plate 200, and the backlight module 20 further includes:

the backlight source is disposed on one side of the light incident surface of the light guide plate 200, wherein visible light emitted from the backlight source enters the light guide plate 200 through the light incident surface and is emitted out from the upper surface of the light guide plate 200, and the arrangement direction of the first light gathering structures 210 is parallel to the light incident surface.

It should be understood that the backlight source may correspond to the backlight source 17 in fig. 4, and the specific implementation may refer to the description related to the embodiment shown in fig. 4, which is not described herein again for brevity.

As shown in fig. 14, an L CD screen 60 is further provided in the present embodiment, and includes a display panel 61 and a backlight module 62, where the backlight module 62 is disposed below the display panel 61, where the display panel 61 may correspond to, for example and without limitation, the liquid crystal display panel in the embodiment of fig. 3, and the backlight module 62 may correspond to the backlight module 20 in the embodiments shown in fig. 6 to 13, and related implementations thereof refer to related descriptions of the foregoing embodiments, and for brevity, no further description is provided herein.

As shown in fig. 15, the present embodiment further provides a biometric detection device 70, which is suitable for an electronic device having a passive light-emitting display device, where the biometric detection device 70 is configured to be disposed below the passive light-emitting display device to achieve an off-screen biometric detection.

The passive light emitting display device is, for example, but not limited to, an L CD display device, for example, the passive light emitting display device is the display device having the backlight module 20.

As described in the above embodiments, the L CD display device includes a display panel and a backlight module 20, the backlight module 20 is disposed below the display panel, the display panel is used for displaying pictures, the backlight module 20 is used for displaying pictures for the display panel, the backlight module 20 includes a light guide plate 200, the light guide plate 200 includes an upper surface 201 and a lower surface 202 opposite to each other, wherein the upper surface 201 of the light guide plate 200 is a surface of the light guide plate 200 facing a side of the display panel, the lower surface 202 of the light guide plate 200 is a surface of the light guide plate 200 facing a side of the display panel, the light guide plate 200 has a first light-gathering structure 210 extending toward the display panel, the upper surface 201 of the light guide plate 200 includes a surface of the first light-gathering structure 210, the first light-gathering structure 210 is used for gathering light rays exiting from the inside of the light guide plate 200 to the upper surface 201 of the light guide plate 200, and the second light-gathering structure 40 is used for gathering light rays exiting from the lower surface 202 of the light guide plate 200 to a light-sensing surface of the biometric detection device 70.

The biometric detection device 70 further includes:

and the image sensor 72 is configured to receive a detection light beam returned from the external object 1000 on the L CD display device, which is converged by the first light-converging structure 210, then transmitted dispersedly, and further converged by the second light-converging structure 40, wherein the detection light beam is used for acquiring the biometric information of the external object 1000.

Here, the biometric feature detection apparatus 70 corresponds to the biometric feature detection apparatus 30 in the foregoing embodiment, and for related implementation, reference may be made to the related description of the foregoing embodiment, and for brevity, detailed description is omitted here.

In some embodiments of the present application, as shown in fig. 15, the biometric detection device 70 further includes: a detection light source 71 for providing a detection light beam required for biometric information detection;

the detection light beam emitted by the detection light source 71 returns from the external object 1000 above the L CD display device, passes through the display panel, enters the backlight module 20, is refracted, dispersed and transmitted by the first light-gathering structure 210 in the backlight module 20, then is further converged by the second light-gathering structure, and finally enters the light-sensing surface of the image sensor 72.

The detection beam is non-visible light. For example, the detection beam may be near infrared light having a wavelength in the range of 780 nm to 2000 nm. More specifically, the detection beam may have a wavelength of 850 nanometers or 940 nanometers. The detection light source may be an infrared light source.

Optionally, in some embodiments of the present application, the detection light source 71 is integrated in the backlight module. More specifically, the detection light source and the backlight light source in the backlight module can be integrally arranged. For example, the detection light source and the backlight light source are integrated in parallel. In other alternative embodiments, the detection light source and the backlight light source may be integrated in a non-parallel manner. This is not particularly limited in the embodiments of the present application.

Further, in some embodiments of the present application, the biometric detection device 70 further includes:

the optical filter (not shown) may be disposed between the backlight module and the light sensing surface of the image sensor, and is configured to filter out optical signals in a wavelength band that is not used for detecting the biological features, so that visible light transmitted to the image sensor may be filtered out by disposing the optical filter, and accuracy of detecting the biological features may be further improved.

In the embodiment of the present application, the optical filter may be specifically configured to filter out visible wavelengths, for example, visible light used for image display. The optical filter may in particular comprise one or more optical filters, which may be configured, for example, as a band-pass filter, to filter out light emitted by the visible light source, while not filtering out infrared light signals. 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.

In some embodiments, the biometric detection device 70 is a fingerprint detection device for detecting fingerprint information from an external object above the L CD display device.

The L CD display device described above may also be referred to as a L CD screen.

As shown in fig. 16, an electronic device 200 is further provided in the embodiment of the present application, and includes an off-screen biometric detection system 80, where the off-screen biometric detection system 80 includes an L CD screen 81, and the L CD screen 81 may be the L CD screen 60 shown in fig. 14, and for specific implementation, reference may be made to the related description of the foregoing embodiment, and for brevity, no further description is provided here.

Further, the electronic device 200 may further include: the biometric characteristic detection device 82, for example, the biometric characteristic detection device 82 may be the biometric characteristic detection device 30 in the embodiment shown in fig. 6 to 13 or the biometric characteristic detection device 70 in fig. 15, and for specific implementation, reference may be made to the related description of the foregoing embodiment, and for brevity, details are not repeated here.

The biometric detection device 82 is configured to receive a detection light beam emitted by a detection light source for biometric detection and passing through the backlight module in the L CD screen after illuminating an external object, where the detection light beam is configured to detect biometric information of the external object.

The electronic device 200 of the embodiment of the present application may include, but is not limited to, a smart phone, a tablet computer, a notebook computer, a smart wearable device, a smart door lock, and the like. In order to realize the basic functions of the electronic device 200, the electronic device 200 in the embodiment of the present application may include other necessary modules or components in addition to the modules or components illustrated below. Taking the electronic device 200 as a smart phone as an example, it may further include a communication module, a speaker, a microphone, a battery, and the like.

When there are a plurality of second light concentrating structures 40, the first light concentrating structure 210 and the second light concentrating structure 40 are both strip-shaped structures. Particularly, when the second light concentrating structure 40 is a second arc-shaped protruding structure and is a structure of the light guide plate 200 itself, the second light concentrating structure 40 is not the same as the dot structure on the light guide plate 200.

In addition, the backlight module 20 according to the above embodiments of the present application may further include a diffusion sheet and a brightness enhancement sheet, and the diffusion sheet and the brightness enhancement sheet are disposed between the light guide plate 200 and the display panel. The diffusion sheet is disposed between the brightness enhancement sheet and the light guide plate 200, or between the display panel and the brightness enhancement sheet.

It should be understood that the upper surface, the lower surface, the light emitting surface, the light incident surface, the light emitting surface, and the like, which may appear in the description of the present application, may be a real surface that actually exists, or may be an imaginary surface, which does not affect the implementation of the technical solution created by the present application, and all belong to the protection scope of the present application. In addition, "overlap", and the like, which may occur in the description of the present application, are to be understood as having the same meaning and being replaceable with each other.

Those skilled in the art will appreciate that the variations, substitutions, alterations, splits, combinations, extensions, etc. of some or all of the embodiments of the present application, and of some or all of the embodiments, without inventive faculty, are intended to be covered by the inventive concepts of the present application and fall within the scope of the present application.

Any reference in this application to "one embodiment," "an embodiment," "example embodiment," etc., means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the application. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment. Further, when a particular feature or structure is described in connection with any embodiment, it is submitted that it is within the purview of one skilled in the art to effect such feature or structure in connection with other ones of the embodiments.

The orientations or positional relationships indicated by "length", "width", "upper", "lower", "left", "right", "front", "rear", "back", "front", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, which may appear in the specification of the present application, are based on the orientations or positional relationships shown in the drawings, and are only for convenience of describing the embodiments of the present application and simplifying the description, but do not indicate or imply that the device or element referred to must have a specific orientation, be constructed in a specific orientation, and be operated, and thus should not be construed as limiting the present application. Like reference numbers and letters refer to like items in the figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures. Meanwhile, in the description of the present application, the terms "first", "second", and the like are used only for distinguishing the description, and are not to be construed as indicating or implying relative importance. In the description of the present application, "plurality" or "a plurality" means at least two or two unless specifically defined otherwise. In the description of the present application, it should also be noted that, unless explicitly stated or limited otherwise, "disposed," "mounted," and "connected" are to be understood in a broad sense, e.g., they may be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; either directly or indirectly through intervening media, or may be interconnected between two elements. The specific meaning of the above terms in the present application can be understood in a specific case by those of ordinary skill in the art.

The above description is only for the specific embodiments of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present application, and shall be covered by the scope of the present application. The terms used in the following claims should not be construed to limit the invention to the specific embodiments disclosed in the specification. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. The utility model provides a biological characteristic detecting system under screen, includes the luminous display device of passive form and biological characteristic detection device, biological characteristic detection device is used for setting up in the luminous display device below of passive form in order to realize that biological characteristic detects under the screen, the luminous display device of passive form includes display panel and backlight unit, backlight unit sets up the below of display panel, display panel is used for the display screen, backlight unit is used for display panel realizes that the picture shows provides visible light, its characterized in that, backlight unit includes:

the biometric detection device includes:

2. The underscreen biometric detection system according to claim 1, wherein the first light gathering structure and the second light gathering structure are both prism structures and are disposed opposite to each other; or

3. The system according to claim 1 or 2, wherein the first light collecting structure comprises a plurality of first prisms arranged in parallel, and the second light collecting structure comprises a plurality of second prisms arranged in parallel, wherein the plurality of first prisms and the plurality of second prisms are arranged opposite to each other and opposite to each other; or

4. The off-screen biometric detection system of claim 3, wherein the first and second prisms disposed opposite one another are identical prisms; or

5. The off-screen biometric detection system of claim 4, wherein the third prisms are sized such that light exiting the lower surface of the light guide plate within a field of view of the biometric detection device is each focused.

6. The system according to claim 3, wherein the first plurality of parallel-arranged arc-shaped protrusions are a plurality of first lenses, the second plurality of parallel-arranged arc-shaped protrusions are a plurality of second lenses, the focal points of the first and second lenses which are opposite to each other coincide, and the ratio of the diameters of the first and second lenses is the ratio of the focal lengths of the first and second lenses.

7. The off-screen biometric detection system of claim 3, wherein the plurality of first prisms are triangular prisms, the third prisms are triangular prisms, and the first and third prisms are at equal apex angles and are oppositely oriented.

8. The system of claim 1, wherein the backlight module further comprises:

9. The system of claim 8, wherein the second focusing structure is disposed on the entire area of the lower surface of the reflective sheet or on a partial area of the lower surface of the reflective sheet, wherein the partial area is an area opposite to the lower surface of the reflective sheet where the field of view of the biometric detection device is located.

10. The system of claim 1, wherein the backlight module further comprises:

11. The underscreen biometric detection system according to claim 1, wherein the second light concentrating structure is disposed at a localized area of the lower surface of the light guide plate; or a local part of one side of the light guide plate, which is opposite to the display panel, extends out of the second light concentrating structure, and the lower surface of the light guide plate comprises the lower surface of the second light concentrating structure; the local area is an area where the view field of the biological feature detection device is over against the lower surface of the light guide plate.