CN210038815U

CN210038815U - Optical image acquisition unit, optical image acquisition system, display screen and electronic equipment

Info

Publication number: CN210038815U
Application number: CN201920848607.3U
Authority: CN
Inventors: 王文轩; 沈健; 姚国峰
Original assignee: Shenzhen Huiding Technology Co Ltd
Current assignee: Shenzhen Goodix Technology Co Ltd
Priority date: 2019-06-05
Filing date: 2019-06-05
Publication date: 2020-02-07
Anticipated expiration: 2029-06-05

Abstract

The application discloses an optical image acquisition unit, an optical image acquisition system, a display screen and an electronic device. The optical image pickup unit includes: the photoelectric sensing unit is arranged on a Thin Film Transistor (TFT) layer of the display screen; an optical converging device disposed over the TFT layer; a diaphragm disposed between the TFT layer and the optical converging device, wherein the diaphragm is provided with a window; the optical converging device is used for transmitting an optical signal reflected by a target object above the display screen to the window, and the optical signal is transmitted to the photoelectric sensing unit through the window. According to the technical scheme, the performance of optical image acquisition can be improved.

Description

Optical image acquisition unit, optical image acquisition system, display screen and electronic equipment

Technical Field

The embodiments of the present application relate to the field of information technology, and more particularly, to an optical image capturing unit, an optical image capturing system, a display screen, and an electronic device.

Background

With the rapid development of the terminal industry, biometric identification technology, such as fingerprint identification technology, is receiving more and more attention.

In the biometric identification technology, the optical image acquisition mode is an important implementation mode. With the development of end products, the requirements for biometric identification are higher and higher, for example, a larger identification area and a smaller assembly space are required, and accordingly, the requirements for optical image capturing products are also higher and higher.

Therefore, how to improve the performance of the optical image capturing product becomes a technical problem to be solved urgently.

SUMMERY OF THE UTILITY MODEL

The embodiment of the application provides an optical image acquisition unit, an optical image acquisition system, a display screen and electronic equipment, and can improve the performance of optical image acquisition products.

In a first aspect, an optical image acquisition unit is provided, comprising: .

The photoelectric sensing unit is arranged on a Thin Film Transistor (TFT) layer of the display screen;

an optical converging device disposed over the TFT layer;

a diaphragm disposed between the TFT layer and the optical converging device, wherein the diaphragm is provided with a window;

the optical converging device is used for converging an optical signal reflected by a target object above the display screen to the window, and the optical signal is transmitted to the photoelectric sensing unit through the window.

In some possible implementations, the light emitting layer of the display screen is disposed between the optical converging device and the TFT layer, and the aperture is disposed in the light emitting layer of the display screen.

In some possible implementations, the light emitting layer of the display screen is disposed below the TFT layer, and the stop is disposed on the base layer of the display screen above the TFT layer.

In some possible implementations, the light emitting layer of the display screen includes a plurality of organic light emitting diode OLED light emitting units, and the diaphragm is disposed between adjacent OLED light emitting units.

In some possible implementations, the optical image acquisition unit further includes:

and the filtering unit is arranged in a light path from the target object to the photoelectric sensing unit and is used for filtering optical signals in a non-target waveband and transmitting the optical signals in a target waveband.

In some possible implementations, the optical filtering unit is disposed above the optical converging device, or disposed on a lower surface of the optical converging device, or disposed on an upper surface of the photoelectric sensing unit.

In some possible implementations, the distance from the lower surface of the optical converging device to the diaphragm is a difference between a focal length of the optical converging device and a distance from an optical center of the optical converging device to a lower plane of the optical converging device.

In some possible implementations, the distance from the lower surface of the diaphragm to the photoelectric sensing unit is determined according to the area of the photoelectric sensing unit and the divergence angle of the light passing through the focal point of the optical converging device.

In some possible implementations, the light signal detected by the photo-sensing unit is used to form one pixel of the captured image.

In some possible implementations, the photo sensor unit is configured to receive the light signal to obtain fingerprint information of the target.

In some possible implementations, the photo-sensing unit is disposed between the TFT devices of the TFT layer.

In some possible implementations, the photo-sensing unit multiplexes the circuits of the TFT layer to implement a photo-detection function.

In a second aspect, an optical image capturing system is provided, which includes the array of optical image capturing units in the first aspect or any possible implementation manner of the first aspect.

In a third aspect, an optical image acquisition system is provided, comprising:

the photoelectric sensing array comprises a plurality of photoelectric sensing units distributed in an array manner and a Thin Film Transistor (TFT) layer arranged on the display screen;

an array of optical converging devices disposed over the TFT layer;

an array of apertures disposed between the TFT layer and the array of optical converging devices, wherein each aperture in the array of apertures is provided with a window;

the optical converging device array is used for converging an optical signal reflected by a target above the display screen to a window of the diaphragm array, and the optical signal is transmitted to the photoelectric sensing array through the window.

In some possible implementations, the light emitting layer of the display screen is disposed between the optical converging device and the TFT layer, and the aperture array is disposed in the light emitting layer of the display screen.

In some possible implementations, the light emitting layer of the display screen is disposed below the TFT layer, and the aperture array is disposed on the base layer of the display screen above the TFT layer.

In some possible implementations, the light emitting layer of the display screen includes a plurality of OLED display units, and the aperture array includes a plurality of apertures, and the plurality of apertures are arranged at intervals in the plurality of OLED light emitting units of the display screen.

In some possible implementations, the optical image acquisition system further includes:

and the filtering layer is arranged in a light path from the target to the photoelectric sensing array and used for filtering optical signals of non-target wave bands and transmitting the optical signals of the target wave bands.

In some possible implementations, the filter layer is disposed above the array of optical converging devices, or disposed on a lower surface of the array of optical converging devices, or disposed on an upper surface of the photo-electric sensing array.

In some possible implementations, the filter layer includes a plurality of filtering units, and each filtering unit corresponds to one photoelectric sensing unit or corresponds to a plurality of photoelectric sensing units.

In some possible implementations, the size of the optical converging device in the optical converging device layer covers only the photo sensing unit, or covers both the photo sensing unit and the light emitting unit of the display screen.

In some possible implementations, the distance from the plane of the diaphragm layer to the sensing array is determined according to the area of the photoelectric sensing unit and the divergence angle of the light passing through the focal point of the optical converging device.

In some possible implementations, the display screen is an OLED screen having a plurality of OLED display units, and the fingerprint detection area of the optical image acquisition system is located in the display area of the OLED screen, and the light emitting unit of the OLED in the fingerprint detection area is used as an excitation light source; the optical signal received by the optical image acquisition system is reflected light formed by irradiating the optical signal emitted by the OLED light-emitting unit to a target object above the OLED screen, and the reflected light carries biological characteristic information of the target object.

In a fourth aspect, there is provided a display screen comprising:

an optical image acquisition system as in the first aspect or any possible implementation form thereof, or an optical image acquisition system as in the second aspect or any possible implementation form thereof.

In some possible implementations, the display screen further includes:

and the first basal layer is arranged above the TFT layer of the display screen, wherein the diaphragm array of the optical image acquisition system is arranged on the basal layer.

In some possible implementations, the display screen further includes:

and the light emitting layer is arranged below the TFT layer.

In some possible implementations, the display screen further includes:

and the second substrate layer is arranged below the light emitting layer of the display screen.

In some possible implementations, the display screen further includes: and the transparent medium layer is arranged between the first basal layer of the display screen and the TFT layer of the display screen.

In some possible implementations, the display screen further includes:

and the light emitting layer is arranged above the TFT layer, wherein the diaphragm array of the optical image acquisition system is arranged on the light emitting layer.

In some possible implementations, the display screen further includes:

and the base layer is arranged below the TFT layer of the display screen.

In some possible implementations, the display screen further includes:

and the display screen accessory layer is arranged above the optical convergence device array of the optical image acquisition system, and comprises a polaroid, a touch device and protective glass.

In some possible implementation manners, the display screen is an OLED screen having a plurality of organic light emitting diode OLED display units, and the fingerprint detection area of the optical image acquisition system is located in the display area of the OLED screen, and the light emitting unit of the OLED in the fingerprint detection area is used as an excitation light source; the optical signal received by the optical image acquisition system is reflected light formed by irradiating the optical signal emitted by the OLED light-emitting unit to a target object above the OLED screen, and the reflected light carries biological characteristic information of the target object.

In a fifth aspect, an electronic device is provided, comprising: a display screen; and the optical image acquisition system of the first aspect or any possible implementation manner of the first aspect, or the optical image acquisition system of the second aspect or any possible implementation manner of the second aspect, wherein the optical image acquisition system is disposed in the display screen.

In some possible implementations, the display screen is an organic light emitting diode OLED display screen, and a light emitting layer of the display screen includes a plurality of OLED light emitting units, where when the optical image capturing system is a biometric identification system, the biometric identification system uses at least a part of the OLED light emitting unit sources as excitation light sources for biometric identification.

In a sixth aspect, an electronic device is provided, comprising: such as the display screen of the fourth aspect or any possible implementation manner of the fourth aspect.

According to the technical scheme, the photoelectric sensing unit is integrated in the TFT layer of the display screen, the optical signal from the top of the display screen is converged to the window of the diaphragm through the optical convergence device, and the optical signal is transmitted to the photoelectric sensing unit through the window to realize image acquisition.

Drawings

FIG. 1 is a schematic view of an optical image acquisition unit according to an embodiment of the present application.

Fig. 2 is a schematic diagram of the operation of the filter unit.

Fig. 3 to 5 are schematic structural views of an optical image pickup unit based on an OLED panel of an ejection type.

Fig. 6 is a schematic view of an optical image capturing unit according to another embodiment of the present application.

Fig. 7 to 9 are schematic structural views of an optical image pickup unit based on a bottom emission type OLED panel.

Fig. 10 to 12 are schematic structural views of an optical image pickup system based on an top-emission type OLED panel.

Fig. 13 to 15 are schematic structural views of an optical image pickup system based on a bottom emission type OLED panel.

Detailed Description

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

The technical solution of the embodiment of the present application may be applied to various electronic devices, for example, portable or mobile computing devices such as smart phones, notebook computers, tablet computers, and game devices, and other electronic devices such as electronic databases, automobiles, and Automated Teller Machines (ATMs), but the embodiment of the present application is not limited thereto.

The technical solution of the embodiment of the present application may be used for optical biometric identification or other optical image acquisition, where the optical biometric identification may be other biometric identification besides optical fingerprint identification, for example, living body identification, and the like, and the embodiment of the present application is not limited thereto. In order to facilitate understanding of the technical solutions of the embodiments of the present application, the following first describes an optical biometric identification technology.

Optical biometric identification technology uses light returned from the top surface of the device display assembly for fingerprint sensing and other sensing operations. The returning light carries information about the object (e.g., a finger) in contact with the top surface, and a specific optical sensing module is implemented by collecting and detecting the returning light. The design of the optical sensing module may be such that the desired optical imaging is achieved by appropriately configuring the optical elements for collecting and detecting the returned light.

Optical biometric identification module, such as optical fingerprint module, it mainly used gathers user's biometric information (for example fingerprint image information). As an example, the biometric identification module may specifically include an optical biometric sensor having an optical sensing array, such as an optical fingerprint sensor; the optical sensing array comprises a plurality of optical sensing units (photosensitive units), and the area of the optical sensing array corresponds to the biological characteristic acquisition area of the biological characteristic identification module. For example, the biometric feature acquisition area is located in the display area of the display screen, so that when a user needs to unlock or verify other biometric features of the electronic device, the user only needs to press a finger on the biometric feature acquisition area located on the display screen, and thus the biometric feature input operation can be achieved. Because the biological characteristic acquisition and detection can be realized in the display area of the display screen, the electronic equipment adopting the structure does not need to specially reserve space on the front surface to set a fingerprint key (such as a Home key), and therefore, a comprehensive screen scheme can be adopted. Thus, the display area of the display screen may extend substantially over the entire front side of the electronic device.

The display screen may be a self-luminous display screen which uses display units having self-luminous properties as display pixels. For example, the display screen may be an Organic Light-Emitting Diode (OLED) display screen, an Active-Matrix Organic Light-Emitting Diode (AMOLED) display screen, or a Micro-LED (Micro-LED) display screen. In other alternative embodiments, the Display screen may also be a Liquid Crystal Display (LCD) or other passive light emitting Display screens, which is not limited in this embodiment of the present application.

On the other hand, the display screen is specifically a touch display screen, which not only can perform image display, but also can detect touch or pressing operation of a user, thereby providing a human-computer interaction interface for the user. For example, in one embodiment, the electronic device may include a Touch sensor, which may be embodied as a Touch Panel (TP), which may be disposed on a surface of the display screen, or may be partially or entirely integrated within the display screen, thereby forming the Touch display screen.

Taking the display screen adopting the OLED screen as an example, the light emitting layer of the display screen has an array of OLED display units arranged in an array, and the biometric identification module can use the OLED display units (i.e., OLED light emitting units) of the OLED screen located in the biometric acquisition area as the excitation light source for biometric detection and identification. Of course, it should be understood that in other alternative implementations, the biometric identification module may also use an internal light source or an external light source to provide the light signal for biometric detection and identification. In this case, the biometric identification module can be applied not only to self-luminous display screens such as OLED screens, but also to non-self-luminous display screens such as liquid crystal display screens or other passive luminous display screens. Moreover, the optical sensing array of the biometric identification module is specifically a Photo detector (or called Photo detector array, or called photosensitive cell array), and includes a plurality of Photo detector/photosensitive cells distributed in an array, and the Photo detector/photosensitive cells can be used as the optical sensing units.

When a finger touches, presses or approaches (for convenience of description, collectively referred to as pressing) a biometric acquisition area, light emitted by a display unit of the biometric acquisition area is reflected at the finger and forms reflected light, wherein the reflected light can carry biometric information of the finger of the user. For example, after the light is reflected by the fingerprint on the surface of the finger of the user, the reflected light carries the fingerprint information of the user because the reflected light of the fingerprint ridge and the fingerprint valley of the fingerprint is different. The reflected light returns to the display screen and is received by the photodetector array of the biometric identification module below the display screen and converted into a corresponding electrical signal, i.e., a biometric detection signal. The electronic device can obtain the biological feature information of the user based on the biological feature detection signal, and can further perform biological feature matching verification, so that the identity verification of the current user is completed, and whether the user has the right to perform corresponding operation on the electronic device is convenient to confirm.

It should be understood that in a specific implementation, the electronic device further includes a protective cover plate, which may be a transparent cover plate, such as a glass cover plate or a sapphire cover plate, located above the display screen and covering the front surface of the electronic device, and the protective cover plate may be further provided with a protective layer. Therefore, in the embodiment of the present application, the pressing of the display screen by the finger may actually mean that the finger presses the cover plate above the display screen or the surface of the protective layer covering the cover plate.

In one embodiment, the optical biometric identification module may be disposed below the display screen to form an off-screen biometric identification module. With the increasing demand for identification areas, the thickness of the modules increases accordingly, which in turn takes up more space. In view of this, the embodiment of the present application provides an improved optical image capturing scheme, which can dispose the module in the display screen, thereby improving the performance of the optical image capturing product.

Fig. 1 shows a schematic diagram of an optical image capturing unit 10 according to an embodiment of the present application, where the optical image capturing unit 10 may constitute one pixel unit of an optical image capturing system.

As shown in fig. 1, the optical image pickup unit 10 may include:

a photoelectric sensing unit 201 arranged on the thin film transistor TFT layer 200 of the display screen;

an optical converging device 401 disposed over the TFT layer 200;

an optical diaphragm 301 disposed between the TFT layer 200 and the optical converging device 401, wherein the optical diaphragm 301 is provided with a window 303;

the optical converging device 401 is configured to converge an optical signal reflected from a target object above the display screen to the window 303, and the optical signal is transmitted to the photoelectric sensing unit 201 through the window 303.

By the arrangement of the optical converging device 401, the diaphragm 301, the window 303 and the photoelectric sensing unit 201, the optical signal from above the optical converging device 401 is converged to the window 303 and transmitted to the photoelectric sensing unit 201 through the window 303. In this way, the photo-sensing unit 201 can detect the light signal from the corresponding region above the optical converging device 401, and can further acquire the pixel value according to the light intensity of the light signal.

The optical signal detected by the photo-sensing unit 201 can be used to form a pixel of the captured image, which pixel represents a characteristic value of the corresponding area above the optical image capturing unit 10. That is, the signal collected by one optical image collection unit 10 forms one pixel of an image, so that one image can be obtained by the signals collected by a plurality of optical image collection units 10.

For example, in the case of fingerprint detection, each optical image capturing unit 10 senses the light intensity converged above the optical image capturing unit, and then converts the light intensity into an electrical signal through the photoelectric sensing unit 201 to form an original fingerprint value, and then forms a fingerprint image of the entire identification area in rows and columns.

In the present embodiment, the optical image capturing unit 10 may be disposed within the display screen, so that the inherent structure within the display screen may be maximally reused.

Specifically, the photo sensor unit 201 is configured to convert an optical signal into an electrical signal. The Photo sensing unit 201 may include a Photodiode (PD), a Photo transistor (Photo transistor), and a TFT device controlling the PD or the Photo transistor. Therefore, the photo-sensing unit 201 may be disposed on a Thin Film Transistor (TFT) layer 200 of the display screen, and the TFT layer 200 may include a plurality of TFT devices 202 for controlling light emission of the OLED light emitting unit, and in an alternative embodiment, the TFT devices in the TFT layer may be multiplexed to be used as TFT devices for controlling PD or photonic. Alternatively, in other embodiments, the optical signal detection circuit may adopt a separate circuit, that is, a circuit without multiplexing the TFT layer, for example, a circuit for realizing the function of the photo sensor unit is added.

In the TFT layer 200, the photo sensing units 201 may be periodically arranged at intervals, for example, one photo sensing unit 201 is arranged at intervals of M TFT devices 202, or one TFT device 202 is replaced with one photo sensing unit 201 in every M +1 TFT devices 202. The distance between the optical sensing units can be set according to factors such as image resolution requirements, the size of an image acquisition area and the like.

In the embodiment of the present application, the photoelectric sensing unit 201 is fabricated by a fabrication process that is the same as or compatible with the TFT device 202, so as to ensure that the photoelectric image capturing unit and the display screen can be integrated together.

The optical converging device 401 may be various devices having a converging function, such as a lens or a microlens. Optionally, the focal point of the optical converging device 401 is located within the window 403.

The periphery of the optical collection device 401 may be filled with a high transmittance low index material, which needs to have a lower index of refraction than the optical collection device 401 to ensure that the most adequate optical signal is collected to the window 303. Alternatively, the optical converging device 401 may be an organic material, such as SiO2, a resin, a transparent adhesive, or the like. Alternatively, the optical converging device 401 may be fabricated by a thermal reflow or gray-scale mask process.

The window 403 is used for light condensed by the optical condensing device 401. Optionally, the number of the windows 403 in the diaphragm 401 may be one or more. Alternatively, the window 403 may be cylindrical, i.e., the window 403 may be a small hole in the diaphragm 401. Optionally, the window 403 has a diameter greater than 100nm to facilitate transmission of the light required for imaging. The diameter of the window 403 is also smaller than a predetermined value to ensure that the stop 401 is able to block unwanted light. That is, the parameters of the window 403 are set such that the optical signal required for imaging by the optical image capturing unit 10 is maximally transmitted to the photo-sensing unit 201, while the undesired light is maximally blocked. For example, the parameters of the window 403 may be set to maximize the transmission of the optical signal incident substantially vertically downward from the corresponding region above the optical image capturing unit 10 to the photo-electric sensing unit 201, and maximize the blocking of other optical signals.

In the embodiment of the present application, the optical converging device 401 may also multiplex optical converging devices in the display screen, or may also use a separate optical converging device, which is not limited in the embodiment of the present application.

Therefore, the optical image collecting unit 10 can be arranged in the display screen, so that the assembly space of the optical image collecting product is saved, and in addition, the optical signal is collected by the optical collecting device, so that the imaging quality can be improved, and the performance of the optical image collecting product can be improved.

It should be understood that the various designs of the embodiments of the present application are applicable to all Light Emitting Diode (LED) type screens, such as OLED, AMOLED, Micro-LED, etc. Hereinafter, a specific structure of the optical image capturing unit will be described by taking the display screen as an OLED screen as an example.

Typical OLED screens may include Top emission type (Top emission) OLED screens and bottom emission type (bottom emission) OLED screens, fig. 1 is a typical structure of an optical image collecting unit based on the Top emission OLED screens, and fig. 6 is a typical structure of an optical image collecting unit based on the bottom emission OLED screens.

Specific structures of the optical image capturing unit based on the top emission type OLED panel and the bottom emission type OLED panel are described below with reference to fig. 1 to 9, respectively.

For a top-emitting OLED panel, the light-emitting layer 300 of the panel is disposed between the optical converging device 401 and the TFT layer 200, and in order to dispose the aperture 301 above the TFT layer 200, in an alternative implementation, the aperture 301 may be disposed in the light-emitting layer 300 of the panel.

Specifically, the light emitting layer 300 of the display screen includes a plurality of OLED light emitting units (or OLED display units, or light emitting pixels) 302, the stop 301 may be disposed between adjacent OLED light emitting units, for example, one stop 301 may be disposed at intervals of N OLED light emitting units, and the stop 301 may correspond to one photo-sensing unit 201 in the TFT layer 200.

With reference to fig. 1, taking fingerprint detection as an example to illustrate a specific working principle, the OLED light-emitting unit 302 of the display screen may emit light to a fingerprint detection area of the display screen, irradiate on the surface of a finger of a user, reflected light with different light intensities enters the display screen after being reflected by the valley and the ridge of the finger, is converged by the optical converging device 401, and is focused on the window 303 of the diaphragm 301, further, the reflected light passes through the window 303 and is transmitted to the photoelectric sensing unit 201, the reflected light carries fingerprint information of the finger of the user, the photoelectric sensing unit 201 receives the reflected light and converts the reflected light into a corresponding electrical signal, i.e., a fingerprint detection signal, and the electronic device may obtain the fingerprint information of the finger of the user based on the fingerprint detection signal.

It should be understood that, in the embodiment of the present application, the OLED light-emitting units and the photoelectric sensing units of the display screen may be in one-to-one correspondence, or one OLED light-emitting unit may correspond to a plurality of photoelectric sensing units, or a plurality of OLED light-emitting units may correspond to one photoelectric sensing unit.

In the embodiment of the present application, the distance d1 between the optical converging device 401 and the stop 301 (i.e. the thickness of the light-emitting layer 300 of the display screen) needs to be set to enable the light signal transmitted through the lens to be converged in the window of the stop, and specifically, the thickness d1 of the light-emitting layer 300 of the display screen can be determined according to the focal length F of the optical converging device 401 and the position of the optical center of the optical converging device 401.

Taking the optical converging device 401 as an example of a lens, in the case of a lens specification, the thickness d1 of the light-emitting layer 300 of the display panel needs to be set to satisfy the formula d1 ═ F-t, where F is the focal length of the lens 401 (i.e., the distance from the optical center O of the lens to the focal point F), and t is the distance from the optical center of the lens 401 to the lower plane of the lens 401, and it should be noted that when the optical center of the lens 401 is above the lower plane of the lens 401, t is a positive value, and when the optical center of the lens 401 is below the lower plane of the lens 401, t is a negative value. Therefore, the thickness of the light-emitting layer 300 of the display panel can be controlled by controlling the values of f and t, and the overall thickness of the display panel can be further controlled.

In the embodiment of the present application, the distance d2 from the plane where the diaphragm 301 is located to the optical sensing unit 201 may be determined according to the photosensitive area of the optical sensing unit 201 and the divergence angle of the light passing through the focal point F of the optical converging device 401. For example, the distance d2 may be set to be small if the light sensing area of the optical sensing unit 201 is large, or the distance d2 may be set to be large if the divergence angle of the light rays of the focal point F is large. Therefore, the thickness of the TFT layer 200 can be controlled by controlling the photosensitive area of the photo-sensing unit 201 and the divergence angle of the light passing through the focal point F of the optical converging device 401, and further the overall thickness of the display screen can be controlled.

Further, in some embodiments of the present application, the optical image capturing unit 10 further includes:

the filtering unit 402 is disposed in an optical path from the target object to the photoelectric sensing unit 201, and is configured to filter an optical signal in a non-target wavelength band and transmit an optical signal in a target wavelength band (i.e., an optical signal in a wavelength band required for optical image acquisition).

The filter unit 402 allows only optical signals in a target wavelength band to pass therethrough (i.e., has high transmittance for optical signals in the target wavelength band), and optical signals other than the target wavelength band have only extremely low transmittance.

Fig. 2 is a schematic diagram of the optical filtering unit, in which an effective light emitting signal for fingerprint detection is incident on the surface of a target object, and enters the display screen after being reflected by the target object, and in the process of being transmitted to the photoelectric sensing unit, in addition to the effective light reflecting signal, an ineffective interference light signal such as ambient stray light, for example, sunlight, also enters the display screen at the same time and is transmitted to the photoelectric sensing unit. By arranging the filtering unit in the optical path from the target object to the photoelectric sensing unit 201, it can be ensured that the optical signal entering the photoelectric sensing unit is an effective light reflection optical signal required by optical image acquisition, and further processing is performed according to the optical signal to obtain required image information, such as a fingerprint image.

Optionally, in some embodiments, the filtering unit may be formed by coating any dielectric layer in the middle of the optical path from the target object to the photoelectric sensing unit. Optionally, the transmittance of the filter unit for light in the target wavelength band is greater than a first threshold, for example 80%, and the transmittance for light in the non-target wavelength band is less than a second threshold, for example 20%.

Optionally, the filtering unit 402 may adopt a stacked structure of multiple layers of inorganic salt metals, oxides, non-metal oxides, and the like, or may also be an organic material having a certain thickness, which is not limited in this embodiment of the application.

Optionally, the filtering unit 402 may be prepared by evaporation, sputtering, spin coating, and the like, which is not limited in this application.

Optionally, the area projection of the filtering unit 402 on the photoelectric sensing unit 201 needs to completely cover the photoelectric sensing unit 201, so as to ensure that the interference light signal is filtered to the maximum extent.

Fig. 3 to 5 illustrate several typical arrangements of the filter unit 402, but the embodiment of the present application is not limited thereto.

For example, the filter unit 402 may be disposed above the optical converging device 401, as shown in fig. 3.

For another example, the filter unit 402 may be disposed on a lower surface of the optical converging device 401, as shown in fig. 4.

For another example, the filter unit 402 may be disposed on an upper surface of the photo sensor unit 201, as shown in fig. 5.

Optionally, the top-emitting OLED panel may further include a substrate layer 100, and optionally, for a non-flexible display panel, the substrate layer 100 may be a hard substrate such as glass, and for a flexible display panel, the substrate layer 100 may be a flexible substrate.

Optionally, the top-emission OLED display may further include a display accessory layer 500, and optionally, the display accessory layer 500 may include a polarizer, a touch-related device, a cover glass, and other accessories, and in practical use, the display accessory layer 500 is usually located at the outermost portion of the display, which is a direct finger touch area.

Specific structures of the optical image capturing unit based on the bottom emission type OLED panel are described with reference to fig. 6 to 8.

For a bottom emission type OLED panel, the light emitting layer 300 of the display panel is disposed below the TFT layer 200, and the first substrate layer 100 is disposed above the TFT layer, and in order to dispose the diaphragm above the photoelectric sensing unit 201, in an alternative implementation, the diaphragm 301 may be disposed on the first substrate layer 100 above the TFT layer 200.

With reference to fig. 6, taking fingerprint detection as an example, explaining the working principle of the optical image acquisition unit based on the bottom-emission OLED screen, an OLED light-emitting unit 302 of the display screen emits light to a fingerprint detection area of the display screen, and irradiates the light on the surface of a finger of a user, after reflection of the finger in the valley and ridge, reflected light with different light intensities enters the display screen, is converged by an optical converging device 401, and is focused on a window 303 of an aperture 301, further, the reflected light passes through the window 303 and is transmitted to a photoelectric sensing unit 201, the reflected light carries fingerprint information of the finger of the user, the photoelectric sensing unit 201 receives the reflected light and converts the reflected light into a corresponding electrical signal, i.e., a fingerprint detection signal, and the electronic device can obtain the fingerprint information of the finger of the user based on the fingerprint detection signal.

In this embodiment, the distance d1 between the optical converging device 401 and the stop 301 (i.e. the thickness of the first substrate layer 100) is also specially designed, for example, determined according to the focal length f of the optical converging device 401 and the position of the optical center of the optical converging device 401, and specific implementation refers to the related description of the foregoing embodiments, and is not repeated here. Therefore, the thickness of the first substrate layer 100 can be controlled by controlling the focal length f of the optical converging device 401 and the distance t from the optical center of the optical converging device 401 to the lower surface of the optical converging device 401, and the overall thickness of the display screen can be further controlled.

In this embodiment, a transparent dielectric layer 600 may further be included between the substrate layer and the TFT layer, and a thickness of the transparent dielectric layer 600, that is, a distance d2 from the plane where the diaphragm is located to the optical sensing unit 201 may be determined according to a photosensitive area of the optical sensing unit 201 and a divergence angle of a light ray passing through a focal point F of the optical converging device 401, which is specifically implemented with reference to the related description of the foregoing embodiment and is not described herein again. Therefore, the thickness of the transparent medium layer 600 can be controlled by controlling the photosensitive area of the optical sensing unit 201 and the divergence angle of the light passing through the focal point F of the optical converging device 401, thereby further controlling the overall thickness of the display screen.

Similar to the previous embodiment, a filtering unit 402 may be disposed in the optical path between the target object and the photoelectric sensing unit 201, for filtering out the optical signal in the non-target wavelength band and transmitting the optical signal in the target wavelength band (i.e. the optical signal in the wavelength band required for optical image acquisition).

Similar to the setting manner of the filtering units in the embodiments shown in fig. 3 to fig. 5, in the optical image capturing unit based on the bottom emission type display screen, the setting manner of the filtering units may be respectively as shown in fig. 7, fig. 8 and fig. 9, and the specific principle refers to the related description of the foregoing embodiments, which is not repeated here.

Optionally, the top-emission OLED panel may further include a second substrate layer 700 disposed below the light-emitting layer 300 of the display panel, optionally, for a non-flexible display panel, the second substrate layer 700 may be a rigid substrate such as glass, for a flexible display panel, the second substrate layer 700 may be a flexible substrate, and the second substrate layer 700 may be integrated with the light-emitting layer 300 of the display panel to protect the light-emitting layer 300 of the display panel.

Therefore, the technical scheme of this application embodiment, through in the TFT layer with photoelectric sensing unit integration at the display screen, through the window that optical convergence device will come from the light signal convergence of display screen top to the diaphragm to make light signal transmit to photoelectric sensing unit in order to realize image acquisition via the window, for with the module setting in the display screen below, can reduce the thickness of product, can also improve imaging quality simultaneously, thereby can promote the performance of optical image acquisition product.

Hereinafter, an optical image capturing system according to an embodiment of the present application will be described with reference to fig. 10 to 15. Fig. 10 to 12 are schematic structural diagrams of an optical image capturing system based on an upper-emission OLED panel, and fig. 13 to 15 are schematic structural diagrams of an optical image capturing system based on a lower-emission OLED panel. Specifically, the optical image acquisition system may include:

an array of optical converging devices disposed over the TFT layer;

The optical image capturing system may be an array of the optical image capturing units 10 described above. Optionally, in some specific embodiments, the number of optical image capturing units in each row or each column of the array is not less than 10.

In some embodiments, in the optical image capturing system, the optical converging device 401 may be disposed only above the photo-sensing unit 201, and the size of the optical converging device 401 may cover only the photo-sensing unit 202, as shown in fig. 10 or 13.

In other embodiments, the optical converging device 401 in the optical image capturing system may be disposed in other manners, for example, the optical converging device 401 may be disposed above the light emitting unit of the display screen, and the optical converging device 401 may be sized to cover both the optical sensing unit 202 and the light emitting unit 302 of the display screen, as shown in fig. 11, 12, 14, and 15.

It should be understood that the above arrangement of the optical converging device is only an example, and the embodiment of the present application is not particularly limited in this regard as long as it can converge the effective reflected light signal above the display screen to the window of the diaphragm to the maximum extent.

It should be noted that, regarding the foregoing description about the photoelectric sensing unit 201, the optical converging device 401, and the diaphragm 301, the setting manner and the working principle of the photoelectric sensing array, the optical converging device array, and the diaphragm array in the optical image acquisition system may be referred to, and for brevity, are not described herein again.

Optionally, in some embodiments, the optical image acquisition system may further include:

Optionally, the filter layer includes a plurality of filter units, and each filter unit corresponds to one photoelectric sensing unit, or corresponds to a plurality of photoelectric sensing units.

Here, the specific arrangement manner and the operation principle of the filter layer refer to the description of the filter unit 402 in the foregoing, and are not described herein again.

It should be understood that in the optical image capturing system, the setting period or number of the optical image capturing units may be set according to the requirements of image resolution, the size of the image capturing area, and other factors, and the embodiment of the present application is not limited thereto.

In the optical image acquisition system, each optical image acquisition unit corresponds to one pixel of an acquired image, and the optical image acquisition system obtains the acquired image through an array of a plurality of optical image acquisition units.

Optionally, the optical image acquisition system may further include:

and the light incidence angle screening unit is arranged above the array and used for transmitting light in a specific incidence angle range and blocking light outside the specific incidence angle range.

For example, the light incident angle screening unit may require a very small incident angle to select a light signal that is incident substantially vertically downward.

Optionally, the optical image capturing system may further include a corresponding processing chip, which is used to further process the captured image, for example, fingerprint identification, fingerprint verification, and the like, which is not limited in this embodiment of the present application.

Embodiments of the present application also provide a display screen, which may include an optical image acquisition system as described above. Therefore, the display screen has not only an image display function but also an optical image capturing function.

It should be understood that the display screen may include various structures included in the display screen in the foregoing embodiments, and the setting manner and the working principle of the optical image acquisition system in the display screen may refer to the description related to the foregoing embodiments, which is not described herein again.

In a specific embodiment, the display screen is an OLED screen having a plurality of organic light emitting diode OLED light emitting units, and the fingerprint detection area of the optical image acquisition system is located in the display area of the OLED screen, and the OLED display unit of the fingerprint detection area is used as an excitation light source; the optical signal received by the optical image acquisition system is reflected light formed by irradiating the optical signal emitted by the OLED display unit to a target object above the OLED screen, and the reflected light carries biological characteristic information of the target object.

The embodiment of the present application further provides an electronic device, which may include a display screen and the optical image capturing system according to the embodiment of the present application, wherein the optical image capturing system is disposed in the display screen. The electronic device may be any electronic device having a display screen.

The display screen may be the display screen described above, such as an OLED screen or other display screens, and for the description of the display screen, reference may be made to the description of the display screen in the above description, and for brevity, no further description is provided here.

Optionally, the display screen is an OLED display screen, a light emitting layer of the display screen includes a plurality of OLED light emitting units, and when the optical image acquisition system is a biometric identification system, the biometric identification system uses at least part of the OLED light emitting units as an excitation light source for biometric identification.

It should be understood that the specific examples in the embodiments of the present application are for the purpose of promoting a better understanding of the embodiments of the present application and are not intended to limit the scope of the embodiments of the present application.

It is to be understood that the terminology used in the embodiments of the present application and the appended claims is for the purpose of describing particular embodiments only and is not intended to be limiting of the embodiments of the present application. For example, as used in the examples of this application and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

Those of ordinary skill in the art will appreciate that the elements of the examples described in connection with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or combinations of both, and that the components and steps of the examples have been described above generally in terms of their functionality in order to clearly illustrate the interchangeability of hardware and software. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

In the several embodiments provided in the present application, it should be understood that the disclosed system and apparatus may be implemented in other manners. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the units is only one logical division, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may also be an electric, mechanical or other form of connection.

The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiments of the present application.

In addition, functional units in the embodiments of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit.

The integrated unit, if implemented in the form of a software functional unit and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present application may be substantially or partially contributed by the prior art, or all or part of the technical solution may be embodied in a software product, which is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present application. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read-only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk, and other various media capable of storing program codes.

While the invention has been described with reference to specific embodiments, the scope of the invention is not limited thereto, and those skilled in the art can easily conceive various equivalent modifications or substitutions within the technical scope of the invention. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. An optical image acquisition unit, comprising:

an optical converging device disposed over the TFT layer;

2. The optical image capturing unit of claim 1, wherein the light emitting layer of the display screen is disposed between the optical converging device and the TFT layer, and the aperture is disposed in the light emitting layer of the display screen.

3. The optical image capturing unit of claim 1, wherein the light emitting layer of the display screen is disposed below the TFT layer and the aperture is disposed in a base layer of the display screen above the TFT layer.

4. The optical image capturing unit of claim 2 or 3, wherein the light emitting layer of the display screen comprises a plurality of OLED light emitting units, and the aperture is disposed between adjacent OLED light emitting units.

5. The optical image capturing unit of any one of claims 1 to 3, further comprising:

6. The optical image capturing unit of claim 5, wherein the filter unit is disposed above the optical converging device, or disposed on a lower surface of the optical converging device, or disposed on an upper surface of the photoelectric sensing unit.

7. The optical image capturing unit of any one of claims 1 to 3, wherein the distance from the lower surface of the optical converging device to the diaphragm is the difference between the focal length of the optical converging device and the distance from the optical center of the optical converging device to the lower plane of the optical converging device.

8. The optical image capturing unit according to any one of claims 1 to 3, wherein a distance from a lower surface of the diaphragm to the photoelectric sensing unit is determined according to an area of the photoelectric sensing unit and a divergence angle of light passing through a focal point of the optical converging device.

9. The optical image capturing unit of any one of claims 1 to 3, wherein the photo-sensing unit is arranged between the TFT devices of the TFT layer.

10. The optical image capturing unit of any one of claims 1 to 3, wherein the optical signal detected by the photo-sensing unit is used to form one pixel of the captured image.

11. An optical image acquisition system, comprising:

an array of optical image acquisition units according to any one of claims 1 to 10.

12. An optical image acquisition system, comprising:

an array of optical converging devices disposed over the TFT layer;

13. The optical image capturing system of claim 12, wherein the light emitting layer of the display screen is disposed between the optical converging device and the TFT layer, and the aperture array is disposed in the light emitting layer of the display screen.

14. The optical image capturing system of claim 12, wherein the light emitting layer of the display screen is disposed below the TFT layer and the aperture array is disposed in a base layer of the display screen above the TFT layer.

15. The optical image capturing system of claim 13 or 14, wherein the light emitting layer of the display screen comprises a plurality of OLED display units, and the aperture array comprises a plurality of apertures, and the plurality of apertures are arranged at intervals in the plurality of OLED light emitting units of the display screen.

16. The optical image acquisition system according to any one of claims 12 to 14, further comprising:

17. The optical image capturing system of claim 16, wherein the filter layer is disposed above the array of optical converging devices, or disposed on a lower surface of the array of optical converging devices, or disposed on an upper surface of the photo-electric sensing array.

18. The optical image capturing system of claim 16, wherein the filter layer comprises a plurality of filter units, each filter unit corresponding to one or more photo sensor units.

19. The optical image capturing system of any one of claims 12 to 14, wherein the size of the optical converging device in the optical converging device layer covers only the photo-sensing unit, or covers both the photo-sensing unit and the light emitting unit of the display screen.

20. The optical image capturing system of any one of claims 12 to 14, wherein the distance from the lower surface of the optical converging device to the stop is the difference between the focal length of the optical converging device and the distance from the optical center of the optical converging device to the lower plane of the optical converging device.

21. The optical image capturing system of any one of claims 12 to 14, wherein the distance from the plane of the stop layer to the sensing array is determined according to the area of the photoelectric sensing unit and the divergence angle of the light passing through the focal point of the optical converging device.

22. The optical image capturing system of any one of claims 12 to 14, wherein the display screen is an OLED screen having a plurality of OLED display units, and the fingerprint detection area of the optical image capturing system is located in the display area of the OLED screen, and the light emitting unit of the OLED of the fingerprint detection area is used as an excitation light source; the optical signal received by the optical image acquisition system is reflected light formed by irradiating the optical signal emitted by the OLED light-emitting unit to a target object above the OLED screen, and the reflected light carries biological characteristic information of the target object.

23. A display screen, comprising:

an optical image acquisition system according to claim 11, or an optical image acquisition system according to any one of claims 12 to 22.

24. The display screen of claim 23, further comprising:

25. The display screen of claim 24, further comprising:

and the light emitting layer is arranged below the TFT layer.

26. The display screen of claim 25, further comprising:

27. A display screen as recited in any one of claims 24-26, wherein the display screen further comprises:

and the transparent medium layer is arranged between the first basal layer of the display screen and the TFT layer of the display screen.

28. The display screen of claim 23, further comprising:

29. The display screen of claim 28, further comprising:

and the base layer is arranged below the TFT layer of the display screen.

30. A display screen as recited in any one of claims 23-26, wherein the display screen further comprises:

31. The display screen according to any one of claims 23 to 26, wherein the display screen is an OLED screen having a plurality of organic light emitting diode OLED light emitting units, and the fingerprint detection area of the optical image capturing system is located in the display area of the OLED screen, and the display unit of the OLED of the fingerprint detection area is used as an excitation light source; the optical signal received by the optical image acquisition system is reflected light formed by irradiating the optical signal emitted by the OLED display unit to a target object above the OLED screen, and the reflected light carries biological characteristic information of the target object.

32. An electronic device, comprising:

a display screen; and

the optical image acquisition system of claim 11, or the optical image acquisition system of any one of claims 12 to 22;

wherein, the optical image acquisition system is arranged in the display screen.

33. The electronic device of claim 32, wherein the display screen is an Organic Light Emitting Diode (OLED) display screen, and wherein the light emitting layer of the display screen comprises a plurality of OLED light emitting units, and wherein when the optical image capture system is a biometric identification system, the biometric identification system employs at least a portion of the OLED light emitting unit sources as excitation light sources for biometric identification.

34. An electronic device, comprising:

a display screen as claimed in any one of claims 23 to 31.