CN107644215B - Optical fingerprint assembly and mobile terminal - Google Patents

Abstract

The invention provides an optical fingerprint assembly and a mobile terminal, wherein the optical fingerprint assembly comprises: the light source comprises a transparent cover plate, a light-emitting display screen and a photosensitive element, wherein the light-emitting display screen is positioned between the transparent cover plate and the photosensitive element, a collimating layer is arranged between the transparent cover plate and the photosensitive element, and the collimating layer is used for converting light rays emitted from the transparent cover plate towards the end face of the photosensitive element into collimated light and transmitting the collimated light rays to the photosensitive element; wherein the light is emitted by the light emitting display screen. Therefore, the definition of fingerprint identification can be effectively improved.

Description

Optical fingerprint assembly and mobile terminal

technical field

The present invention relates to the field of communication technologies, and in particular, to an optical fingerprint assembly and a mobile terminal.

Background technique

With the continuous development of technology, the screen ratio of mobile terminals such as mobile phones is getting higher and higher, and full-screen mobile terminals have become a development trend. For fingerprint recognition of full-screen mobile terminals, conventional capacitive fingerprints cannot penetrate cover glass with a thickness of more than 0.5 mm, so they are no longer suitable for the development trend of full-screen mobile terminals, but optical fingerprints with good penetration. has become a new technological direction.

At present, for the design of fingerprint recognition of a full-screen mobile terminal, the optical fingerprint sensor is generally designed by stacking under the display screen. In the practical application of fingerprint recognition, the fingerprint on the glass cover covered on the display screen is recognized by pressing; however, the light used to identify the fingerprint must at least pass through the display screen and the glass cover, and because the glass cover has a certain Due to the thickness, the light will undergo severe refraction and scattering in the process of returning through the glass cover, resulting in the inability of the fingerprint image to be clearly imaged on the optical fingerprint chip. It can be seen that the existing full-screen optical fingerprint recognition has the problem of low definition; and if the optical fingerprint photosensitive element adopts a silicon-based CMOS (Complementary Metal Oxide Semiconductor) image sensor, although the image recognition clarity can be improved. , but it is only used in small areas. If it is applied to full-screen fingerprint recognition, the size is too large and the cost is too high to be used.

SUMMARY OF THE INVENTION

Embodiments of the present invention provide an optical fingerprint assembly and a mobile terminal to solve the problem of low definition in the existing full-screen optical fingerprint recognition.

An embodiment of the present invention provides an optical fingerprint assembly, comprising: a transparent cover plate, a light-emitting display screen and a photosensitive element, the light-emitting display screen is located between the transparent cover plate and the photosensitive element, and the transparent cover plate is located between the transparent cover plate and the photosensitive element. A collimation layer is arranged between the photosensitive element and the collimation layer is used to convert the light emitted from the transparent cover plate toward the end face of the photosensitive element into collimated light and conduct it to the photosensitive element; Wherein, the light is emitted by the light-emitting display screen.

An embodiment of the present invention further provides a mobile terminal, including the above-mentioned optical fingerprint assembly.

In the embodiment of the present invention, the optical fingerprint assembly includes: a transparent cover plate, a light-emitting display screen and a photosensitive element, the light-emitting display screen is located between the transparent cover plate and the photosensitive element, and the transparent cover plate and the photosensitive element are located between the transparent cover plate and the photosensitive element. A collimation layer is arranged between the photosensitive elements, and the collimation layer is used to convert the light emitted from the transparent cover plate toward the end face of the photosensitive element into collimated light, and conduct it to the photosensitive element; wherein, The light is emitted by the light-emitting display screen. In this way, by arranging a collimation layer between the photosensitive element and the transparent cover plate, the light emitted from the second surface of the transparent cover plate is converted into collimated light, which improves the transmission angle of the light, thereby improving the clarity of the fingerprint image on the photosensitive element. degree, thereby improving the fingerprint recognition function of the optical fingerprint component.

Description of drawings

In order to illustrate the technical solutions of the embodiments of the present invention more clearly, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments of the present invention. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained from these drawings without creative labor.

FIG. 1 is one of the schematic structural diagrams of an optical fingerprint assembly provided by an embodiment of the present invention;

Fig. 2 is a partial enlarged view of area A in Fig. 1;

FIG. 3 is a second schematic structural diagram of an optical fingerprint assembly provided by an embodiment of the present invention.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

Referring to FIGS. 1-3, FIG. 1 is one of the structural schematic diagrams of the optical fingerprint assembly provided by the embodiment of the present invention; FIG. 2 is a partial enlarged view of the area A in FIG. 1; FIG. 3 is the optical fingerprint assembly provided by the embodiment of the present invention. Schematic diagram of the second structure.

As shown in FIG. 1 to FIG. 3 , an embodiment of the present invention provides an optical fingerprint assembly 100 , including: a transparent cover plate 10 , a light-emitting display screen 20 and a photosensitive element 30 , and the light-emitting display screen 20 is located on the transparent cover plate 10 . A collimation layer 40 is provided between the transparent cover plate 10 and the photosensitive element 30 and the photosensitive element 30 , and the collimation layer 40 is used to move from the transparent cover plate 10 to the photosensitive element 30 . The light emitted from the end face of the photosensitive element 30 is converted into collimated light and transmitted to the photosensitive element 30 ; wherein, the light is emitted by the light-emitting display screen 20 .

In the embodiment of the present invention, the transparent cover plate 10 includes a first surface and a second surface disposed opposite to each other, wherein the end surface of the transparent cover plate 10 facing the photosensitive element 30 is the second surface of the transparent cover plate 10, and the transparent cover plate 10 can be a cover plate made of light-transmitting material, such as cover glass, which can encapsulate and protect the optical fingerprint assembly 100; the light-emitting display screen 20 is located on the second side of the transparent cover plate 10, and is used for generating Red, green and blue light are used to display images, and are also used to emit light for fingerprint identification; the photosensitive element 30 is also located on the side of the second surface of the transparent cover 10 to realize the imaging of the fingerprint 200 . Due to a certain thickness of the transparent cover 10 , the light returned by the finger will form part of divergent light after being emitted from the second surface of the transparent cover 10 , so that the fingerprint 200 of the finger cannot be clearly imaged on the photosensitive element 30 . By disposing the collimation layer 40 between the transparent cover plate 10 and the photosensitive element 30 , the light emitted from the second surface of the transparent cover plate 10 can be converted into collimated light by the collimation layer 40 and transmitted to the photosensitive element 30 , so that the fingerprint 200 of the finger can be clearly imaged on the photosensitive element 30 , thereby effectively improving the fingerprint recognition function of the optical fingerprint assembly 100 .

The working principle of the embodiment of the present invention is that in the process of fingerprint recognition, the finger presses on the first surface of the transparent cover plate 10, and the light generated by the light-emitting display screen 20 can be emitted through the transparent cover plate 10; When on the first surface of the transparent cover plate 10, part of the light emitted from the self-luminous display screen 20 will be reflected due to the blocking of fingers, and then emitted from the second surface of the transparent cover plate 10; from the transparent cover plate 10 The light emitted from the second surface of the device is conducted to the photosensitive element 30, so that the fingerprint 200 of the finger is imaged on the photosensitive element 30, thereby realizing the function of fingerprint recognition. Due to a certain thickness of the transparent cover 10 , the light returned by the finger will form part of divergent light after being emitted from the second surface of the transparent cover 10 , so that the fingerprint 200 of the finger cannot be clearly imaged on the photosensitive element 30 . By disposing the collimation layer 40 between the transparent cover plate 10 and the photosensitive element 30 , the light emitted from the second surface of the transparent cover plate 10 can be converted into collimated light by the collimation layer 40 and transmitted to the photosensitive element 30 , so that the fingerprint 200 of the finger can be clearly imaged on the photosensitive element 30 , thereby improving the fingerprint recognition function of the optical fingerprint assembly 100 .

The optical fingerprint assembly 100 provided by the embodiment of the present invention can be applied to a full-screen mobile terminal, and to perform full-screen fingerprint recognition for a full-screen display area, the photosensitive element 30 can be set in a full-screen setting, that is, the photosensitive element 30 is set in the light-emitting In the display area of the display screen 20, at this time, as shown in FIG. The photosensitive element 30 is disposed on the back side of the light-emitting display screen 20 ; and the alignment layer 40 is located between the light-emitting display screen 20 and the photosensitive element 30 .

With the above solution, the collimation layer 40 is located between the light-emitting display screen and the photosensitive element 30. When a finger is pressed on the first surface of the transparent cover 10, the light emitted from the light-emitting display screen 20 emits light. Part of the light will be reflected due to the blocking of the finger, and then emitted from the second surface of the transparent cover 10; the light emitted from the second surface of the transparent cover 10 passes through the light-emitting display screen 20, The collimation layer 40 calibrates the light to be collimated light, and conducts the light to the photosensitive element 30, so that the fingerprint 200 of the finger is imaged on the photosensitive element 30, thereby realizing the function of full-screen fingerprint recognition. Since the collimation layer 40 is arranged to calibrate the light emitted from the transparent cover plate 10 and the light-emitting display screen 20 to the photosensitive element 30, it can solve the problem of the full screen existing in the optical fingerprint identification technology in the prior art. The problem of blurred images during fingerprint recognition, and at the same time solves the problem that large-sized silicon-based CMOS (Complementary Metal Oxide Semiconductor, complementary metal oxide semiconductor) image sensors in the prior art are too expensive and cannot be used to make full-screen fingerprint recognition mobile terminals In addition, the arrangement of the collimation layer 40 can also ensure that the photosensitive area is maximized, so as to solve the problem of insufficient photosensitiveness when the photosensitive element 30 is placed under the light-emitting display screen 20 with low transmittance.

It should be noted that, the optical fingerprint assembly 100 provided by the embodiment of the present invention can also be applied to a full-screen mobile terminal to perform partial fingerprint recognition. That is to say, the photosensitive element 30 is only arranged under the transparent cover 10, and is located outside the display area of the light-emitting display screen 20. This solution can perform partial area fingerprint recognition for a full-screen mobile terminal in the prior art. In the design, when the thickness of the transparent cover plate 10 is large, there is a problem of blurred image when using a common photosensitive element, while using a silicon-based CMOS image sensor for partial fingerprint recognition is expensive, which can improve the image clarity of fingerprint recognition. and to reduce costs.

The following will take the application of the optical fingerprint assembly 100 to a full-screen mobile terminal to perform full-screen fingerprint recognition on the full-screen display area (that is, the alignment layer 40 is disposed between the light-emitting display screen 20 and the photosensitive element 30 ) as an example , to further describe the optical fingerprint assembly provided by the present invention.

In this embodiment, the light-emitting display screen 20 may be a flexible organic light-emitting diode display screen or a glass organic light-emitting diode display screen.

Optionally, the collimation layer 40 is an optical fiber collimation layer.

In this embodiment, the collimation layer 40 may be an optical fiber collimation layer, and the light collimation layer has the characteristics of not only calibrating the angle of the light emitted from the second surface of the transparent cover 10, but also having high light conversion efficiency, which can The weakening of the intensity of the light during the conduction process is effectively reduced, and the light returned by the fingerprint 200 can be clearly imaged on the photosensitive element 30 .

It should be noted that, in other embodiments of the present invention, the collimating layer 40 may also be implemented with other structures, such as a lens structure capable of converting divergent light into collimated light, etc., as long as the collimating layer 40 can realize The structure of the light reflected from the first surface of the lens cover to the transparent cover, and collimated as collimated light after passing through the transparent cover and the light-emitting display screen, shall belong to the protection scope of the present application. Inside.

Optionally, the light-receiving angle of the collimation layer 40 has a positive correlation with the thickness of the display module, wherein the display module includes the transparent cover plate 10 and the light-emitting display screen that are bonded and connected. 20.

In this embodiment, since both the transparent cover 10 and the light-emitting display screen 20 have a certain thickness, the light is blocked by fingers, and the light transmission angle will change during the return process. By setting a certain light receiving angle for the collimating layer 40 , which can effectively increase the light that can pass through the collimation layer 40 , and improve the integrity of the image of the fingerprint 200 on the photosensitive element 30 .

Wherein, there is a mapping relationship that is positively correlated between the light-receiving angle of the collimation layer 40 and the thickness of the display module. The display module includes the transparent cover plate 10 and the light-emitting display screen 20 which are attached and connected, that is, the thickness of the display module is the superposition of the transparent cover plate 10 and the light-emitting display screen 20 . For example, when the thickness of the transparent cover plate 10 and the light-emitting display screen 20 after being superimposed is in the range of 0.9-1.3 mm, the light-receiving angle of the collimation layer 40 is in the range of 6-8°; preferably, the transparent cover plate 10 and the light-emitting display screen 20 The stacked thickness is 1.1 mm, and the light-receiving angle of the collimation layer 40 is 7°.

Optionally, as shown in FIG. 2 , the photosensitive element 30 is an image sensor, and the photosensitive element 30 includes a substrate 31 and a plurality of sensor pixel units 32 arranged on the substrate 31 in an array. The straight layer 40 includes a plurality of optical fiber units 41 .

In this embodiment, the substrate 31 may be a glass substrate, and is used to carry the sensor pixel unit 32; the sensor pixel unit 32 is used for imaging the fingerprint 200, and the optical fiber unit 41 is used to calibrate the light angle. The corresponding relationship between the sensor pixel unit 32 and the optical fiber unit 41 includes one-to-one, one-to-many or many-to-one. For example, as shown in FIG. 1 and FIG. 2 , each of the sensor pixel units 32 corresponds to one of the optical fibers. Unit 41 ; each of the optical fiber units 41 corresponds to at least two of the sensor pixel units 32 ; as shown in FIG. 3 , each of the sensor pixel units 32 corresponds to at least two of the optical fiber units 41 .

Wherein, in the above solution, each of the optical fiber units 41 may be provided with one or more optical fibers.

Optionally, as shown in FIG. 3 , the light-emitting display screen 20 includes at least two light-emitting units 21, and two adjacent light-emitting units 21 are spaced apart, and each of the sensor pixel units 32 is facing the space. set up.

In this embodiment, due to the one-to-one arrangement of the optical fiber unit 41 and the sensor pixel unit 32, the optical fiber collimation layer and the photosensitive element 30 need to be precisely aligned, which is very difficult to manufacture in terms of process, and the cost is high. However, by arranging the sensor pixel units 32 at the distance between two adjacent light-emitting units 21, the space can be fully utilized, thereby maximizing the conduction of the light emitted from the second surface of the transparent cover 10 to the sensor pixel units 32 .

It should be noted that the optical fingerprint assembly 100 is further provided with a switch element 33 , which can be disposed on the substrate 31 , and the switch element 33 is used to control the operation of the light-emitting display screen 20 and the photosensitive element 30 . In this embodiment, in order to make full use of the space and maximally conduct the light emitted from the second surface of the transparent cover 10 to the sensor pixel unit 32 , the switch element 33 may be disposed facing the light emitting unit 21 .

Embodiments of the present invention also relate to a mobile terminal, including the above-mentioned optical fingerprint assembly 100 .

The mobile terminal may be a full-screen mobile terminal, such as a full-screen mobile phone or a full-screen tablet computer.

It should be noted that, the implementation manner of the above embodiment of the optical fingerprint assembly 100 is also applicable to the embodiment of the mobile terminal, and can achieve the same technical effect, which is not repeated here.

The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention. should be included within the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims (13)

1. An optical fingerprint assembly, comprising: a transparent cover plate, a light-emitting display screen and a photosensitive element, the light-emitting display screen is located between the transparent cover plate and the photosensitive element, and the transparent cover plate is located between the transparent cover plate and the photosensitive element. A collimation layer is arranged between the photosensitive element and the collimation layer is used to convert the light emitted from the transparent cover plate toward the end face of the photosensitive element into collimated light and conduct it to the photosensitive element; Wherein, the light is emitted by the light-emitting display screen; The light-emitting display screen includes a light-emitting surface and a back side arranged opposite to each other; wherein, the transparent cover plate is arranged on one side of the light-emitting surface of the light-emitting display screen; the photosensitive element is arranged on the back side of the light-emitting display screen ; and the collimation layer is located between the light-emitting display screen and the photosensitive element; There is a positive correlation between the light-receiving angle of the collimating layer and the thickness of the display module, wherein the display module includes the transparent cover plate and the light-emitting display screen that are attached and connected. 2 . The optical fingerprint assembly according to claim 1 , wherein the alignment layer is an optical fiber alignment layer. 3 . 3 . The optical fingerprint assembly according to claim 2 , wherein when the thickness of the display module ranges from 0.9 to 1.3 mm, the light-receiving angle of the collimation layer ranges from 6 to 8°. 4 . 4 . The optical fingerprint assembly according to claim 3 , wherein the thickness of the display module is 1.1 mm, and the light-receiving angle of the collimating layer is 7°. 5 . 5. The optical fingerprint assembly of claim 1, wherein the photosensitive element is an image sensor. 6 . The optical fingerprint assembly according to claim 5 , wherein the photosensitive element comprises a substrate and a plurality of sensor pixel units arranged on the substrate in an array, and the alignment layer comprises a plurality of optical fiber units. 7 . . 7 . The optical fingerprint assembly of claim 6 , wherein each of the sensor pixel units corresponds to one of the optical fiber units. 8 . 8 . The optical fingerprint assembly of claim 6 , wherein each of the optical fiber units corresponds to at least two of the sensor pixel units. 9 . 9 . The optical fingerprint assembly of claim 6 , wherein each of the sensor pixel units corresponds to at least two of the optical fiber units. 10 . 10 . The optical fingerprint assembly according to claim 6 , wherein the light-emitting display screen comprises at least two light-emitting units, and two adjacent light-emitting units are spaced apart, and each of the sensor pixel units is facing each other. 11 . the spacing settings. 11 . The optical fingerprint assembly according to claim 1 , wherein the light-emitting display screen is a flexible organic light-emitting diode display screen or a glass organic light-emitting diode display screen. 12 . 12. A mobile terminal, characterized by comprising the optical fingerprint assembly according to any one of claims 1 to 11. 13. The mobile terminal according to claim 12, wherein the mobile terminal is a full-screen mobile terminal.

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