WO2023155831A1

WO2023155831A1 - Display screen and electronic device

Info

Publication number: WO2023155831A1
Application number: PCT/CN2023/076456
Authority: WO
Inventors: 林华鑫
Original assignee: 维沃移动通信有限公司
Priority date: 2022-02-21
Filing date: 2023-02-16
Publication date: 2023-08-24
Also published as: CN114518813A

Abstract

Provided in the embodiments of the present application are a display screen and an electronic device. The display screen comprises a display panel, a circular polarizer and a cover plate, which are arranged in a stacked manner, wherein a fingerprint module is provided on the side of the display panel that faces away from the circular polarizer; reflected light emitted from the display panel toward the fingerprint module is elliptically polarized light, and the reflected light is light that is emitted from the display panel toward the circular polarizer and is reflected by an object under test on the cover plate; and the fingerprint module comprises a fingerprint sensor, and a filter layer is arranged on the surface of the fingerprint sensor that faces the display panel. The filter layer enables light in a first polarization direction in the elliptically polarized light to transmit therethrough, so as to be emitted to the fingerprint sensor; and the filter layer can also filter part of the light emitted from the display panel toward the fingerprint module. The first polarization direction is a major-axis direction of the elliptical polarized light.

Description

Displays and Electronics

Cross References to Related Applications

This application claims the priority of a Chinese patent application with application number 202210160426.8 and titled "display screen and electronic equipment" filed with the China Patent Office on February 21, 2022, the entire contents of which are incorporated herein by reference.

technical field

The present application relates to the technical field of electronic equipment, in particular to a display screen and electronic equipment.

Background technique

With the development of electronic equipment, full screens have become a trend, and the application of display screens with fingerprint recognition on electronic equipment is becoming more and more popular.

In related technologies, a display screen usually hides a super macro camera under the display screen. When the light-emitting side of the display substrate emits light, the display substrate has light leakage, that is, the part of the light emitted from the backlight side of the display substrate is emitted toward the fingerprint module. Light leakage causes interference when the fingerprint module recognizes the fingerprint texture information, reduces the overall signal-to-noise ratio and affects the display quality, thereby reducing the recognition accuracy of the fingerprint module.

Contents of the invention

Embodiments of the present application provide a display screen and electronic equipment to solve the technical problems of low image signal-to-noise ratio and low recognition accuracy of fingerprint modules caused by light leakage in the display screen in the related art.

In order to solve the above-mentioned technical problems, the application is implemented as follows:

In the first aspect, an embodiment of the present application provides a display screen, including: a stacked display panel, a circular polarizer, and a touch cover, the side of the display panel facing away from the circular polarizer is provided with a fingerprint module ;

The reflected light emitted from the display panel toward the fingerprint module is elliptically polarized light, and the reflected light is emitted from the display panel toward the circular polarizer and reflected by the measured object on the cover;

The fingerprint module includes a fingerprint sensor, and a filter layer is provided on the surface of the fingerprint sensor facing the display panel, and the filter layer can transmit the light of the first polarization direction in the elliptically polarized light to emit to the fingerprint sensor, and can filter part of the non-polarized light emitted by the display panel towards the fingerprint module, and the first polarization direction is the long axis direction of the elliptically polarized light.

In a second aspect, an embodiment of the present application provides an electronic device, including the above-mentioned display screen.

In the embodiment of the present application, by providing a filter layer on the surface of the fingerprint sensor of the fingerprint module facing the display panel, the filter layer can transmit the light of the first polarization direction in the elliptically polarized light to be incident on the fingerprint sensor, The first polarization direction is the long axis direction of the elliptically polarized light, since the light in the long axis direction of the elliptically polarized light accounts for a relatively large proportion, so that more light in the reflected light can be irradiated on the fingerprint sensor to meet the fingerprint identification; at the same time The filter layer can filter part of the light emitted by the display panel toward the fingerprint module, and can filter part of the light leakage existing in the display panel, so as to reduce the interference caused by the light leakage to the fingerprint module's recognition of fingerprint information, improve the overall signal-to-noise ratio and improve the display quality , thereby improving the accuracy of fingerprint recognition.

Description of drawings

FIG. 1 shows a schematic diagram of a display screen provided by an embodiment of the present application;

Fig. 2 shows a schematic diagram of polarization conversion of reflected light in a display screen provided by an embodiment of the present application;

FIG. 3 shows a schematic diagram of a filter layer and a fingerprint sensor in a first viewing angle in a fingerprint module provided by an embodiment of the present application;

Fig. 4 shows the partially enlarged schematic diagram of place A in Fig. 3;

FIG. 5 shows a schematic diagram of the three-dimensional structure of FIG. 4 .

Reference signs:

10: display panel; 11: substrate glass; 12: light-emitting layer; 121: light-emitting pixel; 13: packaging glass; 20: circular polarizer; 21: quarter wave plate; 22: linear polarizer; 30: touch cover board; 40: fingerprint module; 41: filter layer; 411: rectangular hole; 42: fingerprint sensor; 421: receiving pixel; 43: lens assembly; 44: substrate; 50: measured object.

specific embodiment

The following will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of them. Based on the embodiments in this application, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the scope of protection of this application.

It should be understood that reference throughout the specification to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic related to the embodiment is included in at least one embodiment of the present application. Thus, appearances of "in one embodiment" or "in an embodiment" in various places throughout the specification are not necessarily referring to the same embodiment. Furthermore, the particular features, structures or characteristics may be combined in any suitable manner in one or more embodiments.

In the embodiment of the present application, a display screen is provided. Referring to FIGS. One side of the polarizer 20 is provided with a fingerprint module; the reflected light emitted from the display panel 10 toward the fingerprint module 40 is elliptically polarized light, and the reflected light is emitted by the display panel 10 toward the direction of the circular polarizer 20 and is emitted by the cover plate 30 The light reflected by the measured object 50; the fingerprint module 40 includes a fingerprint sensor 42, and the surface of the fingerprint sensor 42 facing the display panel 10 is provided with a filter layer 41, and the filter layer 41 can make the first polarization direction of the elliptically polarized light The light passes through to strike the fingerprint sensor 42 and can filter part of the light emitted by the display panel 10 toward the fingerprint module. The first polarization direction is the long axis direction of the elliptically polarized light. It can be seen that this embodiment can filter part of the light leakage existing in the display panel, so as to reduce the interference caused by the light leakage to the fingerprint module when identifying the fingerprint information, improve the overall signal-to-noise ratio to improve the display quality, and thereby improve the accuracy of fingerprint identification.

Specifically, as shown in FIG. 1 , the display screen may specifically include: a display panel 10, a circular polarizer 20 and a touch cover 30 arranged in layers, that is, in the direction from bottom to top, the display panel 10, Circular polarizer 20 and touch cover 30 . A fingerprint module 40 is provided on the side of the display panel 10 away from the circular polarizer 20 , that is, the fingerprint module 40 is located on the lower side of the display panel 10 . The surface of the touch cover 30 away from the circular polarizer 20 is used for the touch of the measured object 50, that is, the upper surface of the touch cover 30 is used for The touch of the object under test 50 . In practice, the measured object 50 may be a finger or other measured objects, and the following description will be made by taking the measured object 50 as a finger as an example.

Specifically, the display panel 10 can emit light, which is called outgoing light. The outgoing light sequentially passes through the circular polarizer 20 and the touch cover 30 to the finger, and then is reflected by the finger to form light carrying fingerprint information. At this time, The light is called reflected light, and the reflected light passes through the touch cover 30, the circular polarizer 20, and the display panel 10 to the fingerprint sensor 42 of the fingerprint module in sequence, so that the fingerprint sensor 42 detects the light carrying fingerprint information. Wherein, as shown in Figure 2, the reflected light becomes circularly polarized light after being polarized by the circular polarizer 20 (the process is represented by E1 in Figure 2), and then polarized by the display panel 10 (the process is represented by E2 in Figure 2 ). Indicated) becomes elliptically polarized light.

Specifically, as shown in FIG. 1, a filter layer 41 is provided on the surface of the fingerprint sensor 42 facing the display panel 10, that is, a filter layer 41 is provided on the upper surface of the fingerprint sensor 42, and the filter layer 41 is used to make the elliptical polarization The light of the first polarization direction in the light passes through to be incident on the fingerprint sensor 42, so that the fingerprint sensor 42 detects the light carrying the fingerprint information, wherein the first polarization direction is the long axis direction of elliptically polarized light. In the polarized light, the light in the direction of the long axis is relatively heavy, so that more light in the reflected light can be irradiated on the fingerprint sensor 42 to meet the requirements of fingerprint recognition; at the same time, the filter layer 41 can also filter out the The light emitted by the fingerprint module 40, that is, filters out the part of the light leakage existing in the display panel 10 to reduce the transmittance of the light leakage, improve the overall signal-to-noise ratio to improve the display quality, and thereby improve the accuracy of fingerprint recognition. .

In the embodiment of the present application, as shown in FIG. 1, the fingerprint sensor 42 includes a plurality of receiving pixels 421; the material of the filter layer 41 is a non-transparent material, and the filter layer 41 is provided with a light-transmitting structure at a position opposite to each receiving pixel. , the light-transmitting structure includes a plurality of rectangular holes 411 arranged in an array; the first polarization direction is parallel to the long sides of the rectangular holes 411, so that the light of the first polarization direction in the elliptically polarized light passes through the rectangular holes 411 .

Specifically, the fingerprint sensor 42 includes a plurality of receiving pixels 421, and the receiving pixels 421 can convert optical signals into electrical signals for imaging. As shown in FIG. 3 to FIG. 5 , the filter layer 41 is provided with a light-transmitting structure at a position opposite to each receiving pixel 421 , and the light-transmitting structure includes a plurality of rectangular holes 411 arranged in an array. Wherein, the array includes M rows and N columns, and the M rows include a first preset number of matrices The N columns of shaped holes 411 include a second preset number of rectangular holes 411 . It should be noted that each dotted frame in the filter layer in FIG. 3 corresponds to the corresponding receiving pixel 421 , and FIG. 3 only shows one light-transmitting structure, but in practice, each dotted-line frame is provided with a light-transmitting structure.

Since the filter layer 41 is made of a non-transparent material, that is to say, if the reflected light hits the region (non-rectangular hole 411) of the filter layer 41 with material, it cannot pass through the filter layer 41 to the fingerprint sensor 42. The reflected light irradiates the rectangular hole 411 , and can pass through the rectangular hole 411 and irradiate onto the fingerprint sensor 42 .

Specifically, as shown in FIG. 4, since the first polarization direction is parallel to the long side of the rectangular hole 411, that is, the long axis direction of elliptically polarized light (direction E in the figure) is parallel to the long side of the rectangular hole 411, like this, The light of the first polarization direction in the elliptically polarized light can pass through the rectangular hole 411 to be irradiated onto the fingerprint sensor 42 , so that the fingerprint sensor 42 can detect the light carrying fingerprint information more accurately.

Since the light emitted by the display panel 10 towards the fingerprint module 40 (referred to as light leakage) is non-polarized light, part of the light may irradiate the material area on the filter layer 41 and be reflected back, and part of the light may irradiate the rectangular hole 411, but In this part of the light, some light may be irradiated on the hole wall of the rectangular hole 411 to be refracted and/or reflected back, and only another part of the light can pass through the rectangular hole 411. Compared with the prior art, the filter layer 41 provided in this embodiment It can filter out most of the light leakage to reduce the transmittance of light leakage, improve the overall signal-to-noise ratio to improve the display quality, and thus improve the accuracy of fingerprint recognition.

In the embodiment of the present application, the elliptically polarized light also includes the light of the second polarization direction, and the second polarization direction is the short axis direction of the elliptically polarized light; the second polarization direction is parallel to the short side of the rectangular hole, so that the elliptically polarized light The light in the second polarization direction passes through the rectangular hole to be incident on the fingerprint sensor 42 .

Since the major axis of an ellipse is perpendicular to its minor axis, the longer side of a rectangle is perpendicular to its shorter side. When the first polarization direction is parallel to the long side of the rectangular hole 411, the second polarization direction is parallel to the short side of the rectangular hole 411, that is, the short axis direction of the elliptically polarized light is parallel to the short side of the rectangular hole 411, like this, the elliptical The light of the first polarization direction and the second polarization direction in the polarized light can pass through the rectangular hole 411 and shoot onto the fingerprint sensor 42, which further improves the transmittance of the elliptically polarized light through the rectangular hole, so that the fingerprint sensor 42 is opposite to the fingerprint sensor 42. The light carrying the fingerprint information is detected more precisely.

Specifically, the material of the filter layer 41 can be selected from silicon or aluminum, so that the filter layer 41 can be separated from fingerprints. Sensor 42 is better integrated. Of course, the specific material of the filter layer 41 can also be other materials such as metal, which is not limited in this embodiment, and can be selected according to actual conditions.

In the embodiment of the present application, as shown in FIG. 5 and FIG. 6 , a plurality of rectangular holes 411 are arranged in a matrix.

Specifically, the number of rows and columns of the matrix are the same, and the number of rectangular holes 411 included in each row and column is the same as the number of rows/columns. In this way, the rectangular holes 411 can be uniformly distributed, so that the light of the first polarization direction in the elliptically polarized light can pass through the filter layer 41 uniformly, so as to further improve the accuracy of fingerprint information identification by the fingerprint sensor 42 .

In order to reduce the manufacturing difficulty of the filter layer 41, the number of rows and the number of columns of the matrix can be two, and each row and each column respectively include two rectangular holes 411; or, as shown in Figure 5 and Figure 6, the number of rows of the matrix and the number of columns can be three, and each row and each column respectively include three rectangular holes 411; in addition, as shown in Figure 5 and Figure 6, the ratio range of the first length to the second length is [1.2, 2], Wherein, the first length is the length of the long side of the rectangular hole 411 , and the second length is the length of the short side of the rectangular hole 411 . Of course, this embodiment may not limit the specific arrangement form of the matrix, that is, the specific arrangement of the plurality of rectangular holes 411, and the specific ratio of the first length to the second length, and it is determined according to the actual situation. set up.

In addition, in order to increase the area of the light-transmitting region of the filter layer 41 to increase the transmittance of the filter layer 41, thereby improving the accuracy of fingerprint information identification by the fingerprint sensor 42, the ratio between the area of each light-transmitting structure and the area of the corresponding receiving pixel 421 The ratio is greater than or equal to 0.8, that is, the area of one light-transmitting structure corresponding to one receiving pixel 421 accounts for greater than or equal to 80% of the area of the receiving pixel 421 .

In the embodiment of the present application, as shown in FIG. 1 , a display panel 10 includes a laminated base glass 11 , a light-emitting layer 12 and an encapsulation glass 13 , and a circular polarizer 20 includes a quarter wave plate 21 and a linear polarizer 22 The quarter-wave plate 21 is set on the packaging glass 13, the linear polarizer 22 is set on the quarter-wave plate 21, the touch cover 30 is set on the linear polarizer 22, and the fingerprint module is set on the base glass 11 There is a predetermined distance between the side away from the light emitting layer 12 and the surface of the base glass 11 away from the light emitting layer 12 .

Specifically, as shown in FIG. 1 , the display panel 10 includes a laminated base glass 11, a light emitting layer 12, and an encapsulation glass 13, wherein the light emitting layer 12 is composed of a plurality of light emitting pixels 121, and the light emitting image is The pixels 121 serve as light sources of the display panel 10 and emit light upward.

Specifically, as shown in FIG. 1 , from bottom to top, the display screen includes fingerprint module, base glass 11, light emitting layer 12, packaging glass 13, quarter wave plate 21, linear polarizer 22 and Touch the cover plate 30 . Wherein, in order to make more light emitted upward by the light-emitting pixels 121 can be irradiated on the encapsulation glass 13, a surface (lower surface shown in FIG. A certain distance, the specific value of the distance can be set according to actual needs, which is not limited in this embodiment. There is a predetermined distance between the fingerprint module and the surface of the base glass 11 away from the light-emitting layer 12 (the lower surface shown in FIG. 1 ), so that more reflected light can be irradiated on the fingerprint sensor 42 of the fingerprint module, thereby improving The fingerprint sensor 42 recognizes the accuracy of fingerprint information.

It is worth noting that a quarter-wave plate (1/4 wave plate) is a birefringent single-crystal wave plate of a certain thickness, also known as a phase retarder. The 1/4 wave plate can generate λ/4 optical path difference (ie π/2 phase difference) between the outgoing ordinary light (o light) and extraordinary light (e light). When the linearly polarized light is vertically incident on the 1/4 wave plate, the angle between the polarization direction of the linearly polarized light and the optical axis direction of the 1/4 wave plate is θ. When θ=45°, the outgoing light is circularly polarized light; when θ When ≠45°, the outgoing light is elliptically polarized light; among them, the linearly polarized light can be decomposed into o light and e light whose vibration direction is vertical, and the vibration direction of o light is perpendicular to the incident surface, that is, the vertical optical axis; the vibration of e light The direction is parallel to the plane of incidence, that is, parallel to the optical axis.

In this embodiment, when the reflected light passes through the linear polarizer, it becomes linearly polarized light, and when the linearly polarized light passes through the quarter-wave plate 21, it becomes circularly polarized light. Since there is a gap between the encapsulating glass 13 and the base glass 11, when the circularly polarized light passes through the encapsulating glass 13 and irradiates the base glass 11, ordinary light (o light) and extraordinary light (e light) incident on the circularly polarized light Reflection will occur, because o-light and e-light will have reflection loss, and the reflection will be different instantaneously, and will become elliptically polarized light after passing through the base glass 11 .

In practice, the fingerprint module further includes a lens assembly 43 and a substrate 44 , and from top to bottom, the lens assembly 43 , the fingerprint sensor 42 and the substrate 44 are arranged in sequence. The light of the first polarization direction in the elliptically polarized light is first irradiated onto the lens assembly 43, and the lens assembly 43 is used to send the fingerprint information The emitted light is imaged to the fingerprint sensor 42 for fingerprint detection and/or fingerprint recognition.

It should be noted that the up and down described in the figure are only described in the direction shown in the illustration, and do not represent the actual orientation.

The display screen provided by the embodiment of the present application has the following advantages:

In the embodiment of the present application, the display screen includes a stacked display panel, a circular polarizer and a touch cover. A fingerprint module is provided on the side of the display panel away from the circular polarizer; The light is elliptically polarized light, and the reflected light is the light emitted by the display panel toward the circular polarizer and reflected by the object on the cover; the fingerprint module includes a fingerprint sensor, and the fingerprint sensor is provided with a filter on the surface facing the display panel. Layer, the filter layer can transmit the light of the first polarization direction in the elliptically polarized light to be incident on the fingerprint sensor, and can filter part of the light emitted by the display panel towards the fingerprint module, the first polarization direction is the length of the elliptically polarized light axis direction. It can be seen that this embodiment can filter part of the light leakage existing in the display panel, so as to reduce the interference caused by the light leakage to the fingerprint module when identifying the fingerprint information, improve the overall signal-to-noise ratio to improve the display quality, and thereby improve the accuracy of fingerprint identification.

The embodiment of the present application also provides an electronic device, which may specifically include the above-mentioned display screen.

Specifically, in the embodiment of the present application, electronic devices include but are not limited to mobile phones, tablet computers, notebook computers, palmtop computers, vehicle-mounted terminals, wearable devices, and pedometers. An electronic device includes the above-mentioned display screen.

It should be noted that, in addition to fingerprint information, the reflected light formed by the finger reflection can also carry biological sign information such as pulse, blood oxygen, and rest. That is to say, in addition to detecting fingerprints, the fingerprint sensor of this embodiment can also detect other biological sign information such as pulse, blood oxygen, and rest, so as to perform other functions such as living body detection and human health detection, which enriches the functions of electronic devices.

The advantages of the electronic device are the same as those of the above-mentioned display screen, which will not be repeated here.

It should be noted that each embodiment in this specification is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. For the same and similar parts in each embodiment, refer to each other, that is, Can.

Although alternative embodiments of the embodiments of the present application have been described, those skilled in the art once Knowing the basic inventive concept, additional changes and modifications can be made to these embodiments. Therefore, the appended claims are intended to be interpreted to include alternative embodiments and all changes and modifications that fall within the scope of the embodiments of the application.

Finally, it should also be noted that in this article, relational terms such as first and second are only used to distinguish one entity from another, and do not necessarily require or imply any relationship between these entities. This actual relationship or sequence. Furthermore, the term "comprises", "comprises" or any other variation thereof is intended to cover a non-exclusive inclusion such that an article or terminal equipment comprising a series of elements includes not only those elements but also other elements not expressly listed , or also include elements inherent in such an article or terminal equipment. Without further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the article or terminal device comprising the element. In addition, "and/or" in the specification and claims means at least one of the connected objects, and the character "/" generally means that the related objects are an "or" relationship.

The technical solutions provided by this application have been introduced in detail above. In this paper, specific examples have been used to illustrate the principles and implementation methods of this application. At the same time, for those of ordinary skill in the art, based on the principles and implementation methods of this application, There will be changes in specific implementation methods and application ranges. In summary, the contents of this specification should not be construed as limiting the application.

Claims

A display screen, comprising: a laminated display panel, a circular polarizer, and a touch cover, wherein a fingerprint module is provided on the side of the display panel away from the circular polarizer;

The reflected light emitted from the display panel toward the fingerprint module is elliptically polarized light, and the reflected light is emitted by the display panel toward the circular polarizer and reflected by the measured object on the cover plate after the light;

The fingerprint module includes a fingerprint sensor, and a filter layer is provided on the surface of the fingerprint sensor facing the display panel, and the filter layer can transmit the light of the first polarization direction in the elliptically polarized light to emit to the fingerprint sensor, and can filter part of the light emitted by the display panel towards the fingerprint module, and the first polarization direction is the long axis direction of the elliptically polarized light.
The display screen according to claim 1, wherein the fingerprint sensor comprises a plurality of receiving pixels;

The material of the filter layer is a non-light-transmitting material, and the filter layer is provided with a light-transmitting structure at a position opposite to each of the receiving pixels, and the light-transmitting structure includes a plurality of rectangular holes arranged in an array;

The first polarization direction is parallel to the long side of the rectangular hole, so that the light of the first polarization direction in the elliptically polarized light is transmitted through the rectangular hole.
The display screen according to claim 2, wherein the elliptically polarized light further includes light in a second polarization direction, and the second polarization direction is the short axis direction of the elliptically polarized light;

The second polarization direction is parallel to the short side of the rectangular hole, so that the light of the second polarization direction in the elliptically polarized light is transmitted through the rectangular hole to be irradiated on the fingerprint sensor.
The display screen according to claim 2, wherein a plurality of said rectangular holes are arranged in a matrix.
The display screen according to claim 4, wherein the number of rows and the number of columns of the matrix are both two, and each row and each column respectively include two rectangular holes; or,

The number of rows and the number of columns of the matrix are three, and each row and each column respectively include three of the rectangular holes.
The display screen according to claim 2 or 5, wherein the difference between the first length and the second length The ratio range is [1.2, 2], the first length is the length of the long side of the rectangular hole, and the second length is the length of the short side of the rectangular hole.
The display screen according to claim 2, wherein the ratio of the area of each light-transmitting structure to the area of the corresponding receiving pixel is greater than or equal to 0.8.
The display screen according to claim 2, wherein the filter layer is made of silicon or aluminum.
The display screen according to claim 1, wherein the display panel comprises a laminated base glass, a light-emitting layer and an encapsulation glass, and the circular polarizer comprises a quarter wave plate and a linear polarizer;

The quarter-wave plate is set on the packaging glass, the linear polarizer is set on the quarter-wave plate, the cover plate is set on the linear polarizer, and the fingerprint module is set There is a preset distance between the side of the base glass away from the light-emitting layer and the surface of the base glass away from the light-emitting layer.
An electronic device, comprising the display screen according to any one of claims 1-9.