Display device capable of realizing in-screen fingerprint recognition

Abstract

The present invention provides a display device capable of realizing in-screen fingerprint recognition, comprising: an LCD backlight module, including a light source and a diffusion function layer; a TFT substrate located above the LCD backlight module; a collimation layer located between the diffusion function layer and the TFT substrate; a TFT circuit layer disposed on the side of the TFT substrate away from the collimation layer, which has a first light-transmitting area and a non-light-transmitting area; the first light-transmitting area is used for allowing collimated light emitted by the light source and collimated by the collimation layer to pass through; a fingerprint photosensitive module is disposed on the non-light-transmitting area, which is used to receive and sense target signal light, and the target signal light is formed by the collimated light being reflected by the finger above the TFT circuit layer. The display device of the embodiment of the present invention can significantly reduce the manufacturing cost while realizing in-screen fingerprint recognition.

Description

Technical Field

[0001] The present invention relates to the field of fingerprint recognition technology, and in particular to a display device capable of realizing in-screen fingerprint recognition. Background Art

[0002] The description in this section merely provides background information related to the present disclosure and does not constitute prior art.

[0003] When capacitive fingerprint recognition is applied to mobile phones, it is necessary to open holes in the front cover (ink area) / back cover / side frame of the mobile phone. As a result, this type of fingerprint recognition method will reduce the screen-to-body ratio and destroy the structural integrity of the entire device.

[0004] With the existing mature silicon-based optical fingerprint technology, the fingerprint module with a built-in fingerprint sensor chip needs to be attached to the OLED screen or fixed on the middle frame of the mobile phone under the OLED screen. Therefore, the components used to identify fingerprints will not occupy the surface space or area of ​​the mobile phone, thereby increasing the screen-to-body ratio. However, due to the need to use silicon-based chips, for cost and reliability reasons, it is generally only suitable for realizing small-area fingerprint recognition at a fixed position, and cannot realize large-area fingerprint recognition. And silicon-based is difficult to integrate into the screen.

[0005] It should be noted that the above introduction to the technical background is only for the convenience of providing a clear and complete description of the technical solutions of the present invention and for the convenience of understanding by those skilled in the art. It cannot be considered that the above technical solutions are well known to those skilled in the art simply because these solutions are described in the background technology section of the present invention. Summary of the invention

[0006] Based on the aforementioned defects of the prior art, an embodiment of the present invention provides a display device capable of implementing in-screen fingerprint recognition, aiming to achieve in-screen fingerprint recognition while reducing costs.

[0007] In order to achieve the above object, the present invention provides the following technical solutions.

[0008] A display device capable of realizing in-screen fingerprint recognition, comprising:

[0009] An LCD backlight module comprises a light source and a diffusion function layer located on one side of the light source;

[0010] A TFT substrate located at one side of the LCD backlight module, wherein the TFT substrate is located above the diffusion function layer;

[0011] An alignment layer, located between the diffusion function layer and the TFT substrate;

[0012] A TFT circuit layer is arranged on the side of the TFT substrate away from the collimating layer, and the TFT circuit layer has a first light-transmitting area and a non-light-transmitting area; the first light-transmitting area is used for allowing the collimated light emitted by the light source and collimated by the collimating layer to pass through; a fingerprint photosensitive module is arranged on the non-light-transmitting area, and the fingerprint photosensitive module is used for receiving and sensing target signal light, and the target signal light is formed by the collimated light being reflected by the finger above the TFT circuit layer.

[0013] Preferably, a liquid crystal layer is disposed on a side of the TFT circuit layer facing away from the TFT substrate; and a liquid crystal control circuit for controlling the liquid crystal layer is also disposed on the non-light-transmitting area.

[0014] Preferably, a color filter is provided on the side of the liquid crystal layer away from the TFT circuit layer, and a cover is provided on the side of the color filter away from the liquid crystal layer, the cover has a second light-transmitting area, and an operation area for the finger to press is formed on the second light-transmitting area.

[0015] Preferably, the LCD backlight module, the collimating layer and the TFT substrate are stacked in sequence; that is, the collimating layer is arranged between the LCD backlight module and the TFT substrate.

[0016] Preferably, the collimating layer is implanted in the LCD backlight module, and the LCD backlight module is stacked with the TFT substrate.

[0017] Preferably, the LCD backlight module further comprises a lower brightness enhancement film, and the lower brightness enhancement film is located above the diffusion function layer; and the collimating layer is arranged between the diffusion function layer and the lower brightness enhancement film.

[0018] Preferably, the LCD backlight module further comprises a lower brightness enhancement film and an upper brightness enhancement film, wherein the lower brightness enhancement film is located between the upper brightness enhancement film and the diffusion function layer; and the collimating layer is disposed between the lower brightness enhancement film and the upper brightness enhancement film.

[0019] Preferably, the light source is a surface light source disposed below the diffusion function layer; the LCD backlight module further comprises a reflective sheet, the reflective sheet is disposed below the surface light source, and the reflective sheet overlaps the surface light source.

[0020] Preferably, the light source is arranged on a side of the diffusion function layer; the LCD backlight module further comprises a reflective sheet, the reflective sheet is arranged below the diffusion function layer, and the reflective sheet overlaps the diffusion function layer.

[0021] Preferably, the LCD backlight module further comprises a light guide layer, and the light guide layer is arranged between the reflective sheet and the diffusion function layer.

[0022] Preferably, the fingerprint photosensitive module is an electronic component and circuit integrated on the non-light-transmitting area through a TFT process.

[0023] Preferably, the first light-transmitting area is an opening penetrating the upper and lower surfaces of the TFT circuit layer; or, the first light-transmitting area is a partial area on the TFT circuit layer made of a light-transmitting material.

[0024] By integrating the fingerprint photosensitive module used to identify fingerprint signals into the TFT circuit layer, large-area or even full-screen fingerprint recognition becomes possible. Compared with the use of silicon-based optical fingerprint technology to prepare fingerprint chips, the integration of the fingerprint photosensitive module in the TFT circuit layer makes the preparation process simpler, and the consumables cost and process implementation cost are lower, thus significantly reducing the overall cost.

[0025] In addition, by setting a collimation layer between the TFT substrate and the diffusion function layer, the fingerprint signal strength received by each fingerprint photosensitive module at the vertical corresponding position can be maximized, while the fingerprint signal strength received at the adjacent position can be minimized. In this way, an excellent collimation effect can be achieved, and the imaging quality is high.

[0026] Electronic devices using or equipped with the display device of the embodiment of the present invention do not need to dig holes in the front cover, back cover or side frame of the electronic device, nor do they need to fit the fingerprint module to the screen. Moreover, the fingerprint photosensitive module is integrated into the screen, which is thinner than the fingerprint chip prepared by using silicon-based optical fingerprint technology, and is conducive to the thinness of electronic devices.

[0027] With reference to the following description and accompanying drawings, specific embodiments of the present invention are disclosed in detail, indicating the manner in which the principles of the present invention can be adopted. It should be understood that the embodiments of the present invention are not thereby limited in scope. Within the spirit and scope of the appended claims, the embodiments of the present invention include many changes, modifications and equivalents.

[0028] Features described and / or illustrated with respect to one embodiment may be used in the same or similar manner in one or more other embodiments, combined with features in other embodiments, or substituted for features in other embodiments.

[0029] It should be emphasized that the term “include / comprises” when used herein refers to the presence of features, integers, steps or components, but does not exclude the presence or addition of one or more other features, integers, steps or components. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The drawings described herein are only for explanation purposes and are not intended to limit the scope of the present invention in any way. In addition, the shapes and proportional dimensions of the components in the drawings are only for illustration purposes and are used to help understand the present invention. They do not specifically limit the shapes and proportional dimensions of the components of the present invention. Under the guidance of the present invention, those skilled in the art can select various possible shapes and proportional dimensions to implement the present invention according to specific circumstances. In the drawings:

[0031] Figure 1 This is a schematic diagram of the structure of a display device capable of implementing in-screen fingerprint recognition according to a first embodiment of the present invention;

[0032] Figure 2 This is a schematic diagram of the structure of a display device capable of implementing in-screen fingerprint recognition according to a second embodiment of the present invention;

[0033] Figure 3 for Figure 1 and / or Figure 2 A top view of a TFT circuit layer in a display device capable of implementing in-screen fingerprint recognition according to an embodiment of the present invention;

[0034] Figure 4 for Figure 1 and / or Figure 2 An optical path diagram of a display device capable of implementing in-screen fingerprint recognition according to an embodiment of the present invention;

[0035] FIG. 5A to FIG. 5B is a schematic diagram of the structure in which the collimating layer is arranged at different positions in the LCD backlight module when the light source is a direct backlight source; specifically,

[0036] Figure 5A It is a structural schematic diagram of an LCD backlight module when a collimating layer is disposed between a diffusion functional layer and a lower brightness enhancement film;

[0037] Figure 5B It is a structural schematic diagram of an LCD backlight module when a collimating layer is disposed between an upper brightness enhancement film and a lower brightness enhancement film;

[0038] FIG. 6A to FIG. 6B is a schematic diagram of the structure in which the collimating layer is arranged at different positions in the LCD backlight module when the light source is an edge-type backlight source; specifically,

[0039] Fig. 6A It is a structural schematic diagram of an LCD backlight module when a collimating layer is disposed between a diffusion functional layer and a lower brightness enhancement film;

[0040] Figure 6B It is a structural schematic diagram of an LCD backlight module when a collimating layer is arranged between an upper brightness enhancement film and a lower brightness enhancement film.

[0041] Reference numerals:

[0042] 1. LCD backlight module; 2. Collimation layer; 3. TFT substrate; 4. TFT circuit layer; 5. Liquid crystal layer; 6. Color filter film; 7. Cover plate; 101. Light source; 102. Diffusion function layer; 103. Lower brightness enhancement film; 104. Upper brightness enhancement film; 106. Light guide layer; 107. Reflector; 401. First light-transmitting area; 402. Non-light-transmitting area; 403. Fingerprint photosensitive module; 404. Liquid crystal control circuit. DETAILED DESCRIPTION

[0043] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0044] It should be noted that when an element is referred to as being "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only embodiment.

[0045] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0046] In this specification, the direction of the display device capable of implementing in-screen fingerprint recognition in an embodiment of the present invention in normal use state pointing to or facing the user is defined as "up", and the direction opposite thereto or facing away from the user is defined as "down".

[0047] More specifically, Figure 1 to Figure 2 , Figures 4 to 6B The upward direction indicated in the figure is defined as “up”. Figure 1 to Figure 2 , Figures 4 to 6B The downward direction indicated in FIG. 1 is defined as “down”.

[0048] It is worth noting that the definitions of various directions in this specification are only for the convenience of explaining the technical solution of the present invention, and do not limit the directions of the display device of the embodiment of the present invention in other scenarios including but not limited to use, testing, transportation and manufacturing, which may cause the orientation of the display device to be reversed or the position to be changed.

[0049] The display device provided by the embodiment of the present invention can be used in scenarios including but not limited to under-screen fingerprint unlocking, user identity authentication, and permission acquisition.

[0050] Specifically, when the display device of an embodiment of the present invention is configured in an electronic device, the electronic device can obtain the user's fingerprint feature information based on the display device to match it with the stored fingerprint information to achieve identity authentication of the current user, thereby confirming whether he has the corresponding authority to perform relevant operations on the electronic device.

[0051] It should be noted that the fingerprint information obtained above is only a common embodiment of the user's biometrics. Within the foreseeable scope, those skilled in the art can extend the technical solution of the embodiment of the present invention to any suitable biometric verification scenario. For example, the embodiment of the present invention does not limit the scenario of verification by obtaining the user's iris biometric information.

[0052] The following is an explanation based on the main scenario of obtaining user fingerprint information. However, based on the above description, it can be seen that the protection scope of the embodiments of the present invention is not limited thereto.

[0053] The display device of the embodiment of the present invention can be applied to electronic devices including but not limited to mobile smart phones, tablet electronic devices, computers, GPS navigators, personal digital assistants, smart wearable devices, etc.

[0054] In order to realize the basic functions of the electronic device, the above electronic device may also include other necessary modules or components. Taking a mobile smart phone as an example, it may also include a communication module, a battery, etc.

[0055] It should be noted that other necessary modules or components included in the electronic device can be selected from any suitable existing structures. In order to clearly and briefly illustrate the technical solution provided by the present invention, the above parts will not be described in detail here, and the drawings in the specification are also simplified accordingly. However, it should be understood that the scope of the present invention is not limited thereby.

[0056] like Figure 1 and Figure 2 ,as well as FIG. 5A to FIG. 6BAs shown, the display device capable of implementing in-screen fingerprint recognition in the embodiment of the present invention may include an LCD (Liquid Crystal Display) backlight module 1. The display device in the embodiment of the present invention may specifically be an LCD display device or an LCD display.

[0057] The LCD backlight module 1 at least comprises a light source 101 and a diffusion function layer 102 located on one side of the light source 101. In this embodiment, the light source 101 can be any one of a direct-type backlight source and an edge-type backlight source.

[0058] like FIG. 5A to FIG. 5B The illustrated embodiment is an embodiment in which the light source 101 is a direct-lit backlight source. FIG. 6A to FIG. 6B The illustrated embodiment is an embodiment where the light source 101 is an edge-lit backlight.

[0059] like FIG. 5A to FIG. 5B As shown, in the embodiment where the light source 101 is a direct-type backlight source, the light source 101 may be a surface light source disposed below the diffusion function layer 102. Specifically, the surface light source may be a flat panel light source, an LED surface light source, etc. Thus, the display effect of the display device of the embodiment of the present invention tends to be soft and uniform.

[0060] like FIG. 6A to FIG. 6B As shown, in the embodiment where the light source 101 is an edge-type backlight source, the light source 101 can be arranged on the side of the diffusion function layer 102. Similarly, the edge-type backlight source can also be a flat panel light source, an LED surface light source, etc.

[0061] Of course, the light source 101 in the embodiment of the present invention is not limited to using a surface light source. For example, in the embodiment where there is a light guide layer / light guide plate / light guide sheet, since the light guide layer / light guide plate / light guide sheet can evenly achieve the light emitting effect of a point light source, a point light source may also be used in these embodiments.

[0062] In order to improve the display brightness as much as possible, the light emitted by the direct backlight source or the side-entry backlight source can be transmitted upward as much as possible (in actual application, the light is emitted as much as possible to the outside of the electronic device and as little as possible to the inside of the electronic device). The LCD backlight module 1 can also include a reflective sheet 107. The reflective sheet 107 is used to reflect the light emitted by the light source 101 toward the direction of the diffusion function layer 102, that is, to reflect the light emitted by the light source 101 upward.

[0063] In such FIG. 5A to FIG. 5B In the embodiment where the light source 101 is a direct-type backlight source, the reflective sheet 107 is disposed below the surface light source, and the reflective sheet 107 and the surface light source are overlapped. Then, the light emitted downward by the direct-type backlight source is reflected upward by the reflective sheet 107.

[0064] In such FIG. 6A to FIG. 6B In the embodiment where the light source 101 is an edge-type backlight, the reflective sheet 107 is disposed below the diffusion function layer 102, and the reflective sheet 107 overlaps the diffusion function layer 102. The light emitted laterally from the edge-type backlight is reflected upward by the reflective sheet 107.

[0065] Thus, the reflective sheet 107 can direct as much light as possible from the light source 101 toward the diffusion function layer 102 , that is, toward the outside of the electronic device equipped with the display device of the embodiment of the present invention, so as to improve the display brightness of the display device.

[0066] The LCD backlight module 1 may further include a light guide layer 106 disposed between the reflective sheet 107 and the diffusion function layer 102. Based on the above description, the light guide layer 106 may convert a point light source into a surface light source, or may further improve the display uniformity of the surface light source itself.

[0067] In such FIG. 5A to FIG. 5B In the embodiment where the light source 101 is a direct-lit backlight source, the reflective sheet 107, the light source 101, the light guide layer 106 and the diffusion function layer 102 can be stacked in sequence. That is, in this embodiment, the light guide layer 106 is spaced from the reflective sheet 107, and the light source 101 is sandwiched between the two.

[0068] In such FIG. 6A to FIG. 6B In the embodiment where the light source 101 is an edge-type backlight, the reflective sheet 107 , the light guide layer 106 and the diffusion function layer 102 may be stacked in sequence. In this embodiment, the light guide layer 106 and the reflective sheet 107 are stacked.

[0069] In some embodiments, the LCD backlight module 1 may further include a down brightness enhancement film 103 (DBEF) and an up brightness enhancement film 104 (UBEF). FIG. 5A to FIG. 6B As shown, taking the diffusion function layer 102 as a reference, the lower brightness enhancement film 103 and the upper brightness enhancement film 104 are arranged in sequence from bottom to top.

[0070] Specifically, the lower brightness enhancement film 103 is located above the diffusion functional layer 102 . The upper brightness enhancement film 104 is located above the lower brightness enhancement film 103 , that is, the lower brightness enhancement film 103 is located between the upper brightness enhancement film 104 and the diffusion functional layer 102 .

[0071] The lower brightness enhancement film 103 and the upper brightness enhancement film 104 are both made of a light-transmitting material to have light transmittance. The lower brightness enhancement film 103 and the upper brightness enhancement film 104 can improve the luminous efficiency of the backlight system.

[0072] The diffusion function layer 102 can cause light to be refracted, reflected or scattered multiple times to achieve the effects of optical diffusion and uniform display.

[0073] In one embodiment, the diffusion function layer 102 may be a diffusion layer with a light-transmitting material such as PET (Polyetherimide) or PI (polyimide) as a base material, and diffusion particles are distributed on any surface of the base material. That is, the diffusion function layer 102 may have a diffusion film or a diffusion sheet.

[0074] Of course, the diffusion function layer 102 is not limited to the diffusion film or diffusion sheet in the above embodiments. In other feasible embodiments, any layer having or playing the role of optical diffusion can be the diffusion function layer 102 .

[0075] For example, if diffusion particles are distributed on the surface of any one or both of the lower brightness enhancement film 103 and the upper brightness enhancement film 104 , the lower brightness enhancement film 103 and the upper brightness enhancement film 104 can have or perform the optical diffusion function while performing their respective functions.

[0076] That is to say, the diffusion function layer 102 is not limited to the structure of a diffusion film or a diffusion sheet, and it can also be a known or existing structure in the LCD backlight module 1 to achieve the optical diffusion function.

[0077] Furthermore, the display device of the embodiment of the present invention may further include a TFT (Thin Film Transistor) substrate 3 located above the LCD backlight module 1 , and an alignment layer 2 located between the diffusion function layer 102 and the TFT substrate 3 .

[0078] The TFT substrate 3 is used to provide a support and setting position for the TFT circuit layer 4, and it can adopt any suitable existing structure, such as the known embodiments provided by publication numbers CN107275288A, CN105097667A, etc., which are not limited in the embodiments of the present invention.

[0079] Of course, the TFT substrate 3 is not limited to the above embodiment. In other feasible embodiments, the TFT substrate 3 can be a plate or sheet made of any light-transmitting material, such as glass, or a light-transmitting carrier made of PI, PET, etc.

[0080] The collimating layer 2 is used to convert the divergent light into collimated light. After passing through the collimating layer 2, the random light emitted by the backlight source 101 can be emitted substantially perpendicular to the lower brightness enhancement film 103 or the upper brightness enhancement film 104.

[0081] Likewise, the collimation layer 2 may also adopt any suitable existing structure. For example, the collimation layer 2 may be implemented by various collimation schemes such as optical fiber collimation or shutter collimation of hole arrays.

[0082] In this embodiment, since the alignment layer 2 is disposed between the diffusion function layer 102 and the TFT substrate 3, and since the LCD backlight module 1 includes the above-mentioned multiple layer structures, the positional relationship between the TFT substrate 3 and the LCD backlight module 1 changes with the positional relationship between the alignment layer 2 and the LCD backlight module 1.

[0083] like Figure 1 As shown, the alignment layer 2 can be arranged between the LCD backlight module 1 and the TFT substrate 3. The LCD backlight module 1, the alignment layer 2 and the TFT substrate 3 are stacked in sequence, that is, the upper and lower surfaces of the alignment layer 2 are respectively attached to the lower surface of the TFT substrate 3 and the upper surface of the LCD backlight module 1. At this time, the TFT substrate 3 is spaced from the LCD backlight module 1, and the alignment layer 2 is sandwiched between the two.

[0084] like Figure 2 As shown, the alignment layer 2 can be implanted in the LCD backlight module 1. At this time, the LCD backlight module 1 can be overlapped with the TFT substrate 3, that is, the upper surface of the LCD backlight module 1 and the lower surface of the TFT substrate 3 are attached.

[0085] Since the LCD backlight module 1 has the diffusion function layer 102, the light emitted upward by the light source 101 becomes disordered after passing through the diffusion function layer 102. Therefore, the collimating layer 2 for collimating the light should at least be located downstream of the diffusion function layer 102 along the propagation direction of the light emitted by the light source 101.

[0086] Therefore, when the alignment layer 2 is implanted in the LCD backlight module 1 , it is sufficient that the alignment layer 2 is located above the diffusion function layer 102 .

[0087] For example, Figure 5A and Fig. 6A As shown, the alignment layer 2 can be disposed between the diffusion function layer 102 and the lower brightness enhancement film 103. At this time, taking the diffusion function layer 102 as a reference, the diffusion function layer 102, the alignment layer 2, the lower brightness enhancement film 103, and the upper brightness enhancement film 104 are stacked in sequence from bottom to top.

[0088] Or, if Figure 5B and Figure 6B As shown, the alignment layer 2 can also be disposed between the lower brightness enhancement film 103 and the upper brightness enhancement film 104. At this time, taking the diffusion function layer 102 as a reference, the diffusion function layer 102, the lower brightness enhancement film 103, the alignment layer 2, and the upper brightness enhancement film 104 are stacked in sequence from bottom to top.

[0089] The display device of the embodiment of the present invention may further include a TFT circuit layer 4, a liquid crystal layer 5, a color filter film 6 and a cover plate 7. The TFT circuit layer 4, the liquid crystal layer 5, the color filter film 6 and the cover plate 7 may constitute an LCD display module.

[0090] Among them, the TFT circuit layer 4 is arranged on the side of the TFT substrate 3 away from the collimation layer 2, the liquid crystal layer 5 is arranged on the side of the TFT circuit layer 4 away from the TFT substrate 3, the color filter film 6 (CF) is arranged on the side of the liquid crystal layer 5 away from the TFT circuit layer 4, and the cover plate 7 (CP) is arranged on the side of the color filter film 6 away from the liquid crystal layer 5.

[0091] That is, the TFT substrate 3, the TFT circuit layer 4, the liquid crystal layer 5, the color filter film 6 and the cover plate 7 are sequentially arranged from bottom to top. Further, the TFT substrate 3, the TFT circuit layer 4, the liquid crystal layer 5, the color filter film 6 and the cover plate 7 are sequentially stacked from bottom to top.

[0092] The TFT substrate 3 , the TFT circuit layer 4 , the liquid crystal layer 5 , the color filter film 6 and the cover plate 7 may be implemented by any suitable existing structure, which is not limited in the embodiment of the present invention.

[0093] Combination Figure 3 As shown, the TFT circuit layer 4 has a first light-transmitting area 401 and a non-light-transmitting area 402. The first light-transmitting area 401 is used for allowing the collimated light emitted by the light source 101 and collimated by the collimating layer 2 to pass through.

[0094] A fingerprint photosensitive module 403 is disposed on the non-light-transmitting area 402 , and the fingerprint photosensitive module 403 is used to receive and sense target signal light. The target signal light is collimated light formed by reflection of the finger above the TFT circuit layer 4 .

[0095] Specifically, after the collimated light is collimated by the collimating layer 2, it reaches the finger through the first light-transmitting area 401 and is reflected downward by the finger to form target signal light. The target signal light can reach the fingerprint photosensitive module 403, thereby identifying the fingerprint.

[0096] The TFT circuit layer 4 may be in the form of a thin film, and the fingerprint photosensitive module 403 disposed thereon may be an electronic component and circuit integrated on the non-light-transmitting area 402 through a TFT process. Specifically, a gate material film may be sputtered on the TFT substrate 3, and a circuit wiring pattern may be formed after mask exposure, development, and dry etching. The electronic components involved in the fingerprint photosensitive module 403 may include diodes, triodes, capacitors, resistors, and the like.

[0097] The TFT circuit layer 4 can be conductively connected to an external circuit, thereby realizing a signal connection between the fingerprint photosensitive module 403 and an external image processor. The fingerprint photosensitive module 403 can receive the target signal light reflected from the finger above the TFT circuit layer 4, and can convert the target signal light into an electrical signal to generate a fingerprint image. The fingerprint photosensitive module 403 can further send the fingerprint image to the image processor connected to the signal, and the image processor performs image processing to obtain a fingerprint signal, and performs fingerprint recognition on the fingerprint signal through an algorithm.

[0098] The first light-transmitting region 401 of the TFT circuit layer 4 may be an opening penetrating the upper and lower surfaces of the TFT circuit layer 4. In this case, the portion of the TFT circuit layer 4 located at the edge of the opening constitutes the non-light-transmitting region 402.

[0099] Alternatively, the first light-transmitting region 401 may also be a partial region made of a light-transmitting material on the TFT circuit layer 4. Specifically, the TFT circuit layer 4 may include a region made of a light-transmitting material and a region made of an opaque material. The region made of the light-transmitting material constitutes the first light-transmitting region 401, and the region made of the opaque material constitutes the non-light-transmitting region 402.

[0100] Furthermore, a liquid crystal control circuit 404 for controlling the liquid crystal layer 5 is also provided on the non-light-transmitting area 402. The liquid crystal control circuit 404 can also be integrated on the non-light-transmitting area 402 using a TFT process. It should be noted that the liquid crystal control circuit 404 controlling the liquid crystal layer 5 is a relatively mature technology, and the embodiment of the present invention will not be described in detail here.

[0101] In this embodiment, the cover plate 7 has a second light-transmitting area, and an operation area for being pressed by a finger is formed on the second light-transmitting area.

[0102] The second light-transmitting area may occupy the entire upper surface of the cover plate 7. In this case, the entire cover plate 7 may be made of a light-transmitting material, and there is no area on its upper surface through which light cannot penetrate.

[0103] Alternatively, the second light-transmitting area may only occupy part of the upper surface of the cover plate 7. For example, the cover plate 7 may include a central display area made of a light-transmitting material and a frame area made of an opaque material, wherein the central display area may constitute the second light-transmitting area.

[0104] Furthermore, part or all of the second light-transmitting area constitutes the operating area.

[0105] The cover plate 7 with the second light-transmitting area may be a glass cover plate or a sapphire cover plate. A protective layer may be provided on the upper surface of the cover plate 7. It should be understood that the pressing of the finger may actually be the finger pressing on the cover plate 7, or the finger pressing on the protective layer provided on the upper surface of the cover plate 7.

[0106] The principle of fingerprint recognition using the display device according to the embodiment of the present invention is described below.

[0107] like Figure 4 As shown, when a finger presses the identification area corresponding to the display device, it will come into contact with the upper surface of the cover plate 7.

[0108] The fingerprint ridge is in close contact with the upper surface of the cover plate 7. When the light emitted by the backlight source 101 and transmitted vertically upward through the collimating layer 2 and the first light-transmitting area 401 of the TFT circuit layer 4 encounters the fingerprint ridge, a large proportion of the light is transmitted and a small proportion of the light is reflected. Therefore, the light intensity received by the fingerprint photosensitive module 403 vertically corresponding to the fingerprint ridge is relatively weak.

[0109] There is an air gap between the fingerprint valley and the upper surface of the cover plate 7. The light emitted vertically upward by the backlight source 101 through the collimating layer 2 and the first light-transmitting area 401 of the TFT circuit layer 4 encounters the interface between the cover plate 7 and the air, and a large proportion or even all of the light is vertically reflected downward. Therefore, the light intensity received by the fingerprint photosensitive module 403 vertically corresponding to the fingerprint valley is relatively strong.

[0110] Therefore, the fingerprint photosensitive module 403 integrated on the TFT circuit layer 4 can identify different light intensities, so as to distinguish whether the corresponding position is a fingerprint ridge or a fingerprint valley. The fingerprint photosensitive module 403 can convert light signals of different intensities into electrical signals, amplify and process the signals through the control IC, and restore the changes of the fingerprint valley or ridge at the pressed position to complete the collection of fingerprint information.

[0111] It can be seen that by integrating the fingerprint photosensitive module 403 for identifying fingerprint signals in the TFT circuit layer 4, large-area or even full-screen fingerprint identification becomes possible. In addition, the fingerprint photosensitive module 403 is integrated in the TFT circuit layer 4. Compared with the preparation of fingerprint chips using silicon-based optical fingerprint technology, the preparation process is simpler, the consumables cost and process implementation cost are lower, and the overall cost can be greatly reduced.

[0112] In addition, by providing the collimation layer 2 between the TFT substrate 3 and the diffusion function layer 102, the fingerprint signal strength received by each fingerprint photosensitive module 403 at the vertical corresponding position can be maximized, while the fingerprint signal strength received at the adjacent position can be minimized. In this way, an excellent collimation effect can be achieved, and the imaging quality is high.

[0113] Electronic devices using or equipped with the display device of the embodiment of the present invention do not need to dig holes on the front cover, back cover or side frame of the electronic device, nor do they need to fit the fingerprint module to the screen. Moreover, the fingerprint photosensitive module 403 is integrated into the screen, which is thinner than the fingerprint chip prepared by using silicon-based optical fingerprint technology, and is conducive to the thinness of electronic devices.

[0114] It should be noted that, in the description of the present invention, the terms "first", "second", etc. are only used for descriptive purposes and to distinguish similar objects. There is no order of precedence between the two, and they cannot be understood as indicating or implying relative importance. In addition, in the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0115] It should be understood that the above description is for illustration and not for limitation. Many embodiments and many applications beyond the examples provided will be apparent to those skilled in the art upon reading the above description. Therefore, the scope of the present teachings should not be determined with reference to the above description, but rather with reference to the foregoing claims and the full scope of equivalents to which such claims are entitled. For the purpose of comprehensiveness, all articles and references, including disclosures of patent applications and publications, are incorporated herein by reference. The omission of any aspect of the subject matter disclosed herein in the foregoing claims is not intended to be a waiver of such subject matter, nor should it be considered that the applicant has not considered such subject matter to be part of the disclosed inventive subject matter.

Claims

1. A display device capable of realizing in-screen fingerprint recognition, characterized in that: include: An LCD backlight module comprises a light source and a diffusion function layer located on one side of the light source; A TFT substrate, located above the LCD backlight module; A collimating layer, located between the diffusion function layer and the TFT substrate, and used for converting the divergent light into collimated light; A TFT circuit layer is arranged on the side of the TFT substrate away from the collimating layer, and the TFT circuit layer has a first light-transmitting area and a non-light-transmitting area; the first light-transmitting area is used for allowing the collimated light emitted by the light source and collimated by the collimating layer to pass through; a fingerprint photosensitive module is arranged on the non-light-transmitting area, and the fingerprint photosensitive module is used for receiving and sensing target signal light, and the target signal light is formed by the collimated light being reflected by the finger above the TFT circuit layer.

2. The display device according to claim 1, wherein: A liquid crystal layer is arranged on the side of the TFT circuit layer away from the TFT substrate; and a liquid crystal control circuit for controlling the liquid crystal layer is also arranged on the non-light-transmitting area.

3. The display device according to claim 2, wherein: A color filter is disposed on the side of the liquid crystal layer away from the TFT circuit layer, and a cover is disposed on the side of the color filter away from the liquid crystal layer. The cover has a second light-transmitting area, and an operation area for the finger to press is formed on the second light-transmitting area.

4. The display device according to claim 1, wherein: The LCD backlight module, the alignment layer and the TFT substrate are stacked in sequence; that is, the alignment layer is arranged between the LCD backlight module and the TFT substrate.

5. The display device according to claim 1, wherein: The alignment layer is implanted in the LCD backlight module, and the LCD backlight module is stacked with the TFT substrate.

6. The display device according to claim 1, wherein: The LCD backlight module further comprises a lower brightness enhancement film, and the lower brightness enhancement film is located above the diffusion function layer; The collimating layer is disposed between the diffusion function layer and the lower brightness enhancement film.

7. The display device according to claim 1, wherein: The LCD backlight module further comprises a lower brightness enhancement film and an upper brightness enhancement film, wherein the lower brightness enhancement film is located between the upper brightness enhancement film and the diffusion function layer; The collimating layer is disposed between the lower brightness enhancing film and the upper brightness enhancing film.

8. The display device according to claim 1, wherein: The light source is a surface light source arranged below the diffusion function layer; The LCD backlight module further includes a reflective sheet, which is disposed below the surface light source and overlaps with the surface light source.

9. The display device according to claim 1, wherein: The light source is arranged on the side of the diffusion function layer; The LCD backlight module further includes a reflective sheet, which is disposed below the diffusion function layer and overlaps the diffusion function layer.

10. The display device according to claim 8 or 9, characterized in that: The LCD backlight module further includes a light guide layer, and the light guide layer is arranged between the reflective sheet and the diffusion function layer.

11. The display device according to claim 1, wherein: The fingerprint photosensitive module is an electronic component and circuit integrated on the non-light-transmitting area through a TFT process.

12. The display device according to claim 1, wherein: The first light-transmitting area is an opening that passes through the upper and lower surfaces of the TFT circuit layer; or, The first light-transmitting area is a partial area on the TFT circuit layer made of a light-transmitting material.

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