Display assembly, display device and fingerprint identification method

Abstract

The invention provides a display assembly, a display device and a fingerprint identification method. The display assembly comprises a display panel and a fingerprint identification module located on a light-emitting surface of the display panel, the fingerprint identification module comprises a plurality of fingerprint identification units, and each fingerprint identification unit at least comprises a photoelectric transistor and a switching transistor; the photoelectric transistor comprises a first active layer, a first grid electrode, a first source electrode and a first drain electrode, the manufacturing material of the first active layer comprises an organic semiconductor material, and the first drain electrode and the first grid electrode are partially overlapped to form a first capacitor; the switching transistor includes a second active layer, a second gate, a second source, and a second drain. The fingerprint identification module comprises a first metal layer, a first source electrode, a first drain electrode, a second source electrode and a second drain electrode which are located on the first metal layer, and the first drain electrode is connected with the second source electrode. According to the invention, the collimation of fingerprint reflected light can be improved, the accuracy of fingerprint identification is improved, and the complexity of the structure and process of the display assembly is reduced.

Description

Technical Field

[0001] The present invention belongs to the field of display technology, and more specifically relates to a display component, a display device and a fingerprint recognition method. Background Art

[0002] At present, under-screen optical fingerprint recognition has become the mainstream method for identity recognition in current electronic devices. The optical fingerprint recognition module is placed on the back side of the display panel substrate. The light emitted by the fingerprint recognition light source irradiates the finger, penetrates the display panel after being reflected by the finger, and is then received by the photosensitive element, which converts the optical signal into an electrical signal to achieve fingerprint recognition. In the existing technical solution, the light used for fingerprint recognition has a large light loss after penetrating the entire display panel in the thickness direction of the display panel, which seriously affects the amount of light received by the photosensitive element, and thus affects the accuracy of fingerprint recognition. Summary of the invention

[0003] In view of this, the present application provides a display component, a display device and a fingerprint recognition method to solve the technical problem of low fingerprint recognition accuracy in the prior art.

[0004] In a first aspect, an embodiment of the present application provides a display component, comprising: a display panel and a fingerprint recognition module located on a light-emitting surface of the display panel, the fingerprint recognition module comprising a plurality of fingerprint recognition units, each of which comprises at least one phototransistor and one switch transistor;

[0005] The phototransistor comprises a first active layer, a first gate electrode, a first source electrode and a first drain electrode, the first active layer is made of an organic semiconductor material, and in a direction perpendicular to the display component, the first drain electrode and the first gate electrode partially overlap to form a first capacitor;

[0006] The switch transistor includes a second active layer, a second gate, a second source and a second drain;

[0007] The fingerprint recognition module comprises a first metal layer, wherein a first source electrode, a first drain electrode, a second source electrode and a second drain electrode are all located in the first metal layer, and the first drain electrode and the second source electrode are connected.

[0008] The embodiment of the present application sets the fingerprint recognition module on the light-emitting surface of the display panel. During fingerprint recognition, the light reflected by the finger does not need to penetrate the structural film layer of the display panel to be received by the fingerprint recognition module, which shortens the distance that the fingerprint reflected light needs to be transmitted, increases the collimation of the fingerprint reflected light, avoids the fingerprint reflected light penetrating the structural film layer of the display panel to cause light loss, and ensures the accuracy of fingerprint recognition. At the same time, the fingerprint recognition module uses a phototransistor as a photosensitive element. The structure of the phototransistor is similar to that of the switch transistor. During the manufacturing process, the phototransistor and the switch transistor can share at least part of the process, which can reduce the complexity of the display component structure and process, and is also conducive to reducing the overall thickness of the display component.

[0009] Furthermore, the fingerprint recognition module also includes a second metal layer and a first insulating layer, the second metal layer is located on the side of the first metal layer close to the display panel, and the first insulating layer is located between the first metal layer and the second metal layer; wherein the first gate is located in the second metal layer. The phototransistor is a bottom-gate structure transistor, and the first gate does not block the light directed to the first active layer, thereby ensuring that during the fingerprint recognition stage, the fingerprint reflected light can be directed to the first active layer, so that the phototransistor converts the optical signal into an electrical signal.

[0010] Furthermore, the first active layer and the second active layer are both located on the side of the first insulating layer away from the second metal layer, and are both in contact with the first insulating layer. This is equivalent to the first active layer and the second active layer being located at the same film layer height, which can help reduce the film layer thickness of the fingerprint recognition module, and further help reduce the overall thickness of the display component.

[0011] In one embodiment, the first source and the first gate are not connected, and the fingerprint recognition module includes a fingerprint control signal line, a fingerprint data signal line, a first voltage signal line, and a second voltage signal line; the second gate is electrically connected to the fingerprint control signal line, the second drain is electrically connected to the fingerprint data signal line, the first gate is electrically connected to the first voltage signal line, and the first source is electrically connected to the second voltage signal line, wherein, in the fingerprint recognition stage, the voltage provided by the first voltage signal line to the first gate is greater than the voltage provided by the second voltage signal line to the first source.

[0012] In one embodiment, the first source and the first gate are connected through a via hole on the first insulating layer. The first gate and the first source of the phototransistor are turned on, and the phototransistor always works in the off state. When no light irradiates the surface of the first active layer, the leakage current of the phototransistor is very small. However, in the fingerprint recognition stage, when the reflected light of the fingerprint irradiates the surface of the first active layer, the carriers generated inside the first active layer make the leakage current of the phototransistor significantly larger, which can ensure that the phototransistor has a high light sensitivity.

[0013] The fingerprint recognition module includes a fingerprint control signal line, a fingerprint data signal line and a third voltage signal line;

[0014] The second gate is electrically connected to the fingerprint control signal line, the second drain is electrically connected to the fingerprint data signal line, and the first gate and the first source are both electrically connected to the third voltage signal line. In the fingerprint recognition module, only three signal lines, namely the fingerprint control signal line, the fingerprint data signal line and the third voltage signal line, need to be set, which can also simplify the wiring method in the fingerprint recognition module and save the space occupied by the wiring.

[0015] Optionally, the second gate is located at the second metal layer. Then the switch transistor and the phototransistor are both bottom-gate structures, and the switch transistor and the phototransistor have the same structure and can be manufactured in the same process, thereby further reducing the complexity of the display component structure and process while improving the accuracy of fingerprint recognition.

[0016] Optionally, the second active layer and the first active layer are made of the same layer and the same material. Forming the pattern of the first active layer and the pattern of the second active layer simultaneously in the same process can further simplify the process and reduce the complexity of the process.

[0017] Furthermore, the fingerprint recognition module also includes a plurality of shading parts, which are located on the side of the second active layer away from the display panel, and the orthographic projection of the shading parts on the plane where the second active layer is located covers the second active layer. When the second active layer and the first active layer are made of the same layer and the same material, the shading parts can block the light and prevent the light from irradiating the surface of the second active layer, so that the carriers inside the second active layer are increased, avoiding affecting the switching state of the switching transistor, thereby ensuring the accuracy and performance reliability of fingerprint recognition detection.

[0018] In one embodiment, the fingerprint recognition module further includes a third metal layer, the third metal layer is located on a side of the first metal layer away from the display panel, and the second gate is located on the third metal layer. During the fingerprint recognition stage, the second gate located on a side of the second active layer away from the display panel can be reused as a light shielding portion.

[0019] Specifically, the display panel includes a plurality of pixel areas and a non-pixel area between adjacent pixel areas, wherein the positive projection of the fingerprint recognition unit on the display panel is located in the non-pixel area. When displaying, the fingerprint recognition unit will not block the light output of the pixel area, thereby ensuring that the setting of the fingerprint recognition module does not affect the display effect.

[0020] Based on the same inventive concept, an embodiment of the present application provides a display device, characterized in that it includes the display component provided by any embodiment of the present application.

[0021] Based on the same inventive concept, an embodiment of the present application provides a fingerprint recognition method, which is applicable to the display component provided by any embodiment of the present application. The fingerprint recognition method includes:

[0022] The switch transistor and the phototransistor are both controlled to be turned off, and the leakage current of the phototransistor causes the first capacitor to be charged and accumulate an initial charge;

[0023] Control the switch transistor to turn on, discharge the first capacitor, read the initial charge through the second drain, and then control the switch transistor to turn off;

[0024] After the phototransistor receives the light reflected by the finger, the leakage current increases, and the first capacitor is charged to accumulate the fingerprint charge;

[0025] The switch transistor is controlled to be turned on, the first capacitor is discharged, and the fingerprint charge is read through the second drain.

[0026] The display component, display device and fingerprint recognition method provided by the present application have the following beneficial effects:

[0027] The fingerprint recognition module is set on the light-emitting surface of the display panel. During fingerprint recognition, the light reflected by the finger does not need to penetrate the structural film layer of the display panel to be received by the fingerprint recognition module, which shortens the distance that the fingerprint reflected light needs to be transmitted, increases the collimation of the fingerprint reflected light, avoids the fingerprint reflected light penetrating the structural film layer of the display panel to cause light loss, and ensures the accuracy of fingerprint recognition. At the same time, the fingerprint recognition module uses a phototransistor as a photosensitive element. The structure of the phototransistor is similar to that of the switch transistor. During the manufacturing process, the phototransistor and the switch transistor can share at least part of the process, which can reduce the complexity of the display component structure and process, and is also conducive to reducing the overall thickness of the display component. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without paying any creative labor.

[0029] Figure 1 A schematic diagram of a partial film structure of a display component provided in an embodiment of the present application;

[0030] Figure 2 for Figure 1 A schematic diagram of the optical path of the light used by the display component for fingerprint detection during the fingerprint recognition stage in the embodiment;

[0031] Figure 3A schematic diagram of another partial film layer structure of a display component provided in an embodiment of the present application;

[0032] Figure 4 A schematic diagram of another partial film layer structure of a display assembly provided in an embodiment of the present application;

[0033] Figure 5 A schematic diagram of a circuit structure of a fingerprint recognition unit in a display component provided in an embodiment of the present application;

[0034] Figure 6 for Figure 5 Timing diagram of the fingerprint recognition circuit in the embodiment;

[0035] Figure 7 A schematic diagram of a circuit structure of a fingerprint recognition module in a display component provided in an embodiment of the present application;

[0036] Figure 8 A schematic diagram of another partial film layer structure of a display assembly provided in an embodiment of the present application;

[0037] Fig. 9 A schematic diagram of another partial film layer structure of a display assembly provided in an embodiment of the present application;

[0038] Fig.10 Fig. 9 A schematic diagram of a circuit structure of a fingerprint recognition unit in an embodiment;

[0039] Fig.11 A partial top view schematic diagram of a display assembly provided in an embodiment of the present application;

[0040] Fig.12 A schematic diagram of another partial film layer structure of a display assembly provided in an embodiment of the present application;

[0041] Fig.13 A schematic diagram of a display device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0042] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution 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 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 those skilled in the art without creative work are within the scope of protection of the present invention.

[0043] The terms used in the embodiments of the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. The singular forms "a", "said" and "the" used in the embodiments of the present invention and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.

[0044] In order to reduce the light loss when light penetrates the display panel and improve the accuracy of fingerprint recognition. Related technologies have proposed the following technical solutions: integrating the photosensitive element into the array substrate of the display panel, so that during fingerprint recognition, the light reflected by the finger only needs to penetrate the packaging structure of the display panel, the light-emitting device layer and part of the film layer in the array substrate to be received by the photosensitive element; or integrating the photosensitive element between two adjacent light-emitting devices, so that the light reflected by the finger only needs to penetrate the packaging structure of the display panel and part of the film layer of the light-emitting device layer to be received by the photosensitive element. Although the above solution can shorten the distance that the fingerprint reflected light needs to be transmitted to a certain extent, it will also increase the complexity of the panel structure and process, and is usually only applicable to organic light-emitting display devices.

[0045] Another solution is proposed in the related art, which is to place the switch transistor and photosensitive element (photodiode) used for fingerprint identification on the packaging film of the display panel. Although the distance that the fingerprint reflected light needs to be transmitted is further shortened, the switch transistor and the photosensitive element are quite different in structure and preparation process, so the switch transistor and the photosensitive element need to be made separately, which increases the complexity of the panel manufacturing process and the overall thickness of the fingerprint identification module composed of the switch transistor and the photosensitive element is also relatively large.

[0046] Based on the above problems, the embodiments of the present application provide a display component, which is applicable to any type of display device in the prior art, such as LCD (Liquid Crystal Display), OLED (Organic Electroluminesence Display), micro LED (micro Light Emitting Diode) display, etc. The fingerprint recognition module integrated with the phototransistor and the switch transistor is arranged on the light-emitting surface of the display panel, which can improve the accuracy of fingerprint recognition while reducing the complexity of the display component structure and process.

[0047] Figure 1 A schematic diagram of a local film layer structure of a display component provided in an embodiment of the present application. Figure 2 for Figure 1 A schematic diagram of the optical path of the light used by the display component for fingerprint detection during the fingerprint recognition stage in the embodiment.

[0048] like Figure 1As shown, the display assembly includes: a display panel 10 and a fingerprint recognition module 20 located on the light-emitting surface of the display panel 10. The light-emitting surface of the display panel 10 is the surface of the display panel on the side where the display panel displays the picture. The display panel 10 is any one of an organic light-emitting display panel, a liquid crystal display panel, and a micro diode display panel. Figure 1 In the figure, only the display panel is an organic light-emitting display panel for illustration. The display panel 10 includes a base substrate 101, an array substrate 102, a display layer 103 and a packaging structure 104. The light-emitting surface of the display panel 10 is the outer surface of the packaging structure 104 on the side away from the display layer 103. The base substrate 101 can be a flexible substrate or a rigid substrate; the array substrate 102 includes a plurality of pixel circuits, and only a driving transistor 1021 in the pixel circuit is illustrated in the figure; the display layer 103 includes a pixel definition layer 1031 and a plurality of light-emitting devices 1032, and only one light-emitting device 1032 is illustrated in the figure. The light-emitting device 1032 includes an anode 31, a light-emitting layer 32 and a cathode 33 stacked in sequence, and the anode 31 is electrically connected to the driving transistor 1021 through a via; the packaging structure 104 is used to encapsulate the display layer 103 to isolate water and oxygen, so as to ensure the service life of the light-emitting device. The packaging structure 104 may be a rigid packaging, including a packaging cover and a sealing adhesive; the packaging structure 104 may be a thin film packaging, including at least one organic packaging layer and at least one inorganic packaging layer stacked alternately.

[0049] The fingerprint recognition module 20 includes a plurality of fingerprint recognition units, each of which includes at least one phototransistor 1 and a switch transistor 2 connected to the phototransistor 1. The figure shows only one fingerprint recognition unit. The phototransistor 1 is a photosensitive element, which can receive the light reflected from the fingerprint and convert the light signal into an electrical signal during the fingerprint recognition stage. The switch transistor 2 is electrically connected to the phototransistor 1, and the switch transistor 2 is used to read the fingerprint electrical signal and output the electrical signal to the fingerprint data processing module, and finally the electrical signal is processed in the fingerprint data processing module to generate fingerprint information.

[0050] The phototransistor 1 includes a first active layer 11, a first gate 12, a first source 13 and a first drain 14. The material of the first active layer 11 includes an organic semiconductor material. In a direction perpendicular to the display component, the first drain 14 and the first gate 12 partially overlap to form a first capacitor Cs. The organic semiconductor material is pentacene, 6,13-bis(triisopropylsilylethynyl)pentacene (TIPS-pentacene), copper phthalocyanine (CuPc), (bis-naphtho[2,3-b:2′,3′-f]thieno[3,2-b]thiophene) (DNTT), 2,6-bis(methoxyphenyl)anthracene (BOPAnt), poly-3-hexylthiophene (P3HT), poly-[bis(3-dodecyl-2-thienyl)-2,2'-bithiophene-5, Any one or more of] (Poly[bis(3-dodecyl-2-thienyl)-2,2'-dithiophene-5,5'-diyl], PQT-12), PDVT-10 (poly[2,5-bis(alkyl)pyrrolo[3,4-c]-1,4(2H,5H)-dione-alt-5,5'-di(thiophene-2-yl)-2,2'-(E)-2-(2-(thi ophen-2-yl)vinyl)thio-phene]), and dialkyl-substituted pyrrolopyrrole diketo-thiophene-bithiophene-thiophene copolymer (DPP-DTT). The first active layer 11 can be made by solution coating and then etching to form a pattern of the first active layer 11. The first active layer 11 can also be formed by evaporation. Organic semiconductor materials have strong absorption of light. The first active layer 11 serves as a light-sensing layer. When light is irradiated onto the surface of the first active layer 11, each absorbed photon generates an electron-hole pair inside the first active layer 11. Due to the action of the electric field, the electron-hole is separated to generate charge carriers. The charge carriers migrate inside the material to form a current, thereby realizing the conversion of the optical signal into an electrical signal. Different organic semiconductor materials have different sensitive bands to light. In fact, fingerprint recognition can be achieved by matching the light-sensitive band of the organic semiconductor material with the fingerprint recognition light source. The first active layer uses an organic semiconductor material that is sensitive to visible light, such as an organic semiconductor material that is sensitive to green light, and the corresponding fingerprint recognition light source emits green light; the first active layer uses an organic semiconductor material that is sensitive to infrared light, and the corresponding fingerprint recognition light source emits infrared light.

[0051] The working states of the phototransistor 1 include a dark state and a bright state. The dark state of the phototransistor 1 is a state when no light is irradiated to the surface of the first active layer 11. In the dark state, a bias voltage is applied to the phototransistor 1, and a small leakage current will exist in the first active layer 11. Correspondingly, the bright state of the phototransistor 1 is a state when light is irradiated to the surface of the first active layer 11. In the bright state, a small leakage current and a photocurrent generated by light excitation exist in the first active layer 11.

[0052] The switch transistor 2 includes a second active layer 21, a second gate 22, a second source 23 and a second drain 24; wherein the second active layer 21 may be made of a silicon-based semiconductor material, such as a single-crystal silicon semiconductor or a polycrystalline silicon semiconductor; or may be made of an organic semiconductor material. The material for making the second active layer 21 includes any one or more of Pentacene, TIPS-pentacene, CuPc, DNTT, BOPAnt, P3HT, PQT-12, PDVT-10, DPP-DTT, 2,7-dioctyl[1]benzothieno[3,2-b]benzothiophene (C8-BTBT), [4,4,9,9-tetrakis(4-hexylphenyl)-s-benzodiindeno[1,2-b:5,6-b']dithiophene]-benzothiadiazole copolymer (C16-IDTBT), 2,8-difluoro-5,11-bis(triethylsilylethynyl)bithiopheneanthracene (diF-TES-ADT), and 2,9-diphenyl-dinaphthyl[2,3-b:2',3'-f]thieno[3,2-b]thiophene (Dph-DNTT). The second active layer 21 may be made of the same material as the first active layer 11 , or the material of the second active layer 21 may be different from the material of the first active layer 11 .

[0053] The fingerprint recognition module 20 includes a first metal layer 41, wherein the first source 13, the first drain 14, the second source 23 and the second drain 24 are all located in the first metal layer 41, and the first drain 14 and the second source 23 are connected. That is, during the display component manufacturing process, the first source 13, the first drain 14, the second source 23 and the second drain 24 can be manufactured in the same etching process, which can reduce the complexity of the process. Optionally, as Figure 1 As shown, the first drain electrode 14 and the second source electrode 23 are integrally formed to form a common electrode, one end of the common electrode serves as the first drain electrode 14 , and the other end of the common electrode serves as the second source electrode 23 .

[0054] like Figure 1As shown, the fingerprint recognition module 20 also includes a passivation layer 91 on the first active layer 11 and the second active layer 21, wherein the passivation layer 91 can simultaneously play the role of insulation and flattening. The display component also includes a protective cover plate 92 located on the fingerprint recognition module 20, and the protective cover plate 92 can be a rigid cover plate or a flexible cover plate. Optionally, an anti-impact layer (not shown in the figure) is also provided between the passivation layer 91 and the protective cover plate 92, and the anti-impact layer can buffer the external force borne by the display component to protect the components in the display component from external force damage.

[0055] The display component provided in the embodiment of the present application is capable of realizing a fingerprint recognition function, wherein the fingerprint recognition light source required to realize the fingerprint recognition function can be an external light source, such as a visible light source or an infrared light source. When applied, the external light source is set on the side of the display panel away from the fingerprint recognition module; when the display panel is an organic light-emitting display panel, the light-emitting device in the display panel can be reused as a fingerprint recognition light source. Figure 2 Only the light emitting device 1032 is reused as a fingerprint recognition light source for illustration. Figure 2 As shown, in the fingerprint recognition stage, the light emitted by the light emitting device 1032 is emitted from the light emitting surface of the display panel 10, and then penetrates the fingerprint recognition module 20 and the protective cover 92 in sequence before irradiating the user's finger 88. The light reflected by the finger penetrates the protective cover 92 again and irradiates the first active layer of the phototransistor 1. The first active layer absorbs the light reflected by the fingerprint and converts the optical signal into an electrical signal.

[0056] In a fingerprint recognition method applicable to the display component provided in the embodiment of the present application, taking the working process of a fingerprint recognition unit as an example, fingerprint recognition includes: a startup phase, an initial signal reading phase, a fingerprint signal accumulation phase and a fingerprint signal reading phase.

[0057] In the startup phase, the control switch transistor 2 and the phototransistor 1 are both turned off, and the phototransistor 1 is in a dark state. There is a small leakage current in the phototransistor 1, so that the first capacitor Cs formed between the first drain 14 and the first gate 12 of the phototransistor 1 is charged to accumulate a small amount of initial charge, which is recorded as the initial charge Q0.

[0058] In the initial signal reading stage, the switch transistor 2 is controlled to be turned on, so that the second source 23 and the second drain 24 of the switch transistor 2 are connected, and since the first drain 14 and the second source 23 are connected, the first capacitor Cs is discharged, and the initial charge Q0 is read through the second drain 24, and then the switch transistor 2 is controlled to be turned off.

[0059] In the fingerprint signal accumulation stage, after the phototransistor 1 receives the light reflected by the finger, the phototransistor 1 is in the bright state, and the first active layer 11 generates charge carriers inside after being irradiated by light, so the current in the phototransistor 1 increases, so that the amount of charge accumulated by the first capacitor Cs increases, which is recorded as the fingerprint charge Q1. When the finger is pressed on the surface of the display component, the ridge of the fingerprint of the finger is in direct contact with the surface of the display component, and the light emitted by the fingerprint recognition light source is reflected on the interface where the fingerprint ridge and the display component contact, and then received by the phototransistor 1; there is air between the fingerprint valley of the finger and the surface of the display component, and the light emitted by the fingerprint recognition light source penetrates the interface between the display component and the air, and then is reflected by the fingerprint valley, and then penetrates the interface between the display component and the air before being received by the phototransistor 1. Therefore, the light intensity of the light reflected by the ridge is greater than the light intensity of the light reflected by the valley. Correspondingly, in the fingerprint signal accumulation stage, the photocurrent generated in the phototransistor receiving the light reflected by the ridge is greater than the photocurrent generated in the phototransistor receiving the light reflected by the valley, and then the charge accumulated on the first capacitor in the phototransistor receiving the light reflected by the ridge is more. Therefore, in the subsequent calculation and processing, the fingerprint valleys and fingerprint ridges can be distinguished according to the size of the fingerprint charge.

[0060] In the fingerprint signal reading stage, the switch transistor 2 is controlled to be turned on, and the second source 23 and the second drain 24 of the switch transistor 2 are connected again, the first capacitor Cs is discharged, and the fingerprint charge Q1 is read through the second drain 24 .

[0061] The initial charge Q0 and the fingerprint charge Q1 are read respectively through the second drain, and the initial charge Q0 and the fingerprint charge Q1 are transmitted to the fingerprint data processing module (the module in the system mainboard). The fingerprint data processing module collects the fingerprint detection signals returned by multiple fingerprint recognition units and performs calculations to finally generate fingerprint information.

[0062] The display component provided by the embodiment of the present application sets the fingerprint recognition module on the light-emitting surface of the display panel. During fingerprint recognition, the light reflected by the finger does not need to penetrate the structural film layer of the display panel to be received by the fingerprint recognition module, which shortens the distance that the fingerprint reflected light needs to be transmitted, can increase the collimation of the fingerprint reflected light, avoid the fingerprint reflected light penetrating the structural film layer of the display panel to cause light loss, and improve the accuracy of fingerprint recognition. At the same time, the fingerprint recognition module uses a phototransistor as a photosensitive element. The structure of the phototransistor is similar to that of the switch transistor. During the manufacturing process, the phototransistor and the switch transistor can share at least part of the process, which can reduce the complexity of the display component structure and process, and is also conducive to reducing the overall thickness of the display component.

[0063] In addition, the photosensitivity effect (also known as the photosensitivity effect) of the photosensitive element is related to the order of magnitude that can be achieved by dividing the photocurrent by the dark current, that is, the greater the difference between the photocurrent and the dark current, the better the photosensitivity effect, and the more sensitive the fingerprint recognition. Among them, the dark current is the leakage current of the photosensitive element in the dark state (in the state without light irradiation), and the photocurrent is the current generated by the light excitation of the photosensitive element in the bright state (in the state with light irradiation). In the fingerprint recognition scheme of the related art, a photodiode is used as a photosensitive element, and its leakage current in the dark state is at the nA level. It is usually necessary to make the photosensitive area of ​​the photosensitive diode relatively large to ensure the photosensitivity effect of the photosensitive diode, which results in a fingerprint recognition module composed of a switching transistor and a photosensitive diode occupying a large area. The fingerprint recognition module is set on the display surface of the display panel, and the fingerprint recognition module has a high light shielding effect on the display panel, which affects the display effect. In the embodiment of the present application, a fingerprint recognition unit is formed by using a phototransistor and a switching transistor. The leakage current of the phototransistor in the dark state is at the pA level, that is, the leakage current of the phototransistor in the dark state is much smaller than the leakage current of the photodiode in the dark state. Therefore, the phototransistor of the present application can have a good photosensitivity effect while being relatively small in size. The phototransistor is arranged on the light-emitting surface of the display panel without blocking the light emitting of the display panel.

[0064] Continue to refer Figure 1 As shown, the fingerprint recognition module 20 further includes a second metal layer 42 and a first insulating layer 51, wherein the second metal layer 42 is located on the side of the first metal layer 41 close to the display panel 10, and the first insulating layer 51 is located between the first metal layer 41 and the second metal layer 42; wherein the first gate 12 is located on the second metal layer 42. That is, the first gate 12 of the phototransistor 1 is located on the side of the first active layer 11 close to the display panel 10, and the phototransistor 1 is a transistor with a bottom gate structure, and the first gate 12 will not block the light directed to the first active layer 11, thereby ensuring that the fingerprint reflected light can be directed to the first active layer 11 during the fingerprint recognition stage, so that the phototransistor 1 converts the optical signal into an electrical signal.

[0065] In one embodiment, if Figure 1 As shown in the figure, the second gate 22 of the switch transistor 2 is also located in the second metal layer 42. The second gate 22 of the switch transistor 2 can be made of the same layer and material as the first gate 12 of the phototransistor 1. In this embodiment, the switch transistor and the phototransistor are both bottom-gate structures, and the switch transistor and the phototransistor have the same structure and can be made in the same process, which can further reduce the complexity of the display component structure and process while improving the accuracy of fingerprint recognition.

[0066] Continue to refer Figure 1As shown, the first active layer 11 and the second active layer 21 are both located on the side of the first insulating layer 51 away from the second metal layer 42, and are both in contact with the first insulating layer 51. In the manufacturing process, after the patterning process of the first gate 12 is completed, the first insulating layer 51 is manufactured on the first gate 12; then the first metal layer 41 is manufactured on the first insulating layer 51; the first metal layer 41 is patterned to form the first source 13, the first drain 14, the second source 23 and the second drain 24; then the first active layer 11 and the second active layer 21 are manufactured, and the two ends of the first active layer 11 are respectively connected to the first source 13 and the first drain 14, and the two ends of the second active layer 21 are respectively connected to the second source 23 and the second drain 24. The first active layer 11 and the second active layer 21 are both in contact with the first insulating layer 51, which is equivalent to the first active layer 11 and the second active layer 21 being located at the same film layer height, which can help reduce the film thickness of the fingerprint recognition module, and thus help reduce the overall thickness of the display component.

[0067] In one embodiment, the first active layer and the second active layer are made of the same layer and the same material, that is, the pattern of the first active layer and the pattern of the second active layer are formed simultaneously in the same process, which can further simplify the process and reduce the complexity of the process.

[0068] When the second active layer and the first active layer are made of the same material, the second active layer and the first active layer have the same sensitive wavelength band to light. Based on this, in order to ensure the performance reliability of the switching transistor during the fingerprint recognition stage, the present application embodiment proposes another display component, such as Figure 3 As shown, Figure 3 Another schematic diagram of the partial film structure of the display component provided by the embodiment of the present application. The first source electrode 13, the first drain electrode 14, the second source electrode 23 and the second drain electrode 24 are all located in the first metal layer 41; the first gate electrode 12 and the second gate electrode 22 are all located in the second metal layer 42, and the first active layer 11 and the second active layer 21 are made of the same layer and the same material, and are both in contact with the first insulating layer 51. The fingerprint recognition module 20 also includes a plurality of light shielding parts 61 (only one is shown in the figure), one light shielding part 61 corresponds to a switching transistor 2, and the light shielding part 61 is located on the side of the second active layer 21 away from the display panel 10, and the orthographic projection of the light shielding part 61 on the plane where the second active layer 21 is located covers the second active layer 21. Among them, the material of the light shielding part 61 can be a metal material or an organic light-absorbing material, etc. In practice, the light shielding part can be made of a corresponding material according to the photosensitive band of the organic semiconductor material used in the first active layer to ensure that the light shielding part blocks the light of the band. The shading portion can block light and prevent the light from irradiating the surface of the second active layer so as to increase the carriers inside the second active layer, thereby avoiding affecting the switching state of the switching transistor and ensuring the accuracy and performance reliability of fingerprint recognition detection.

[0069] Optionally, in the fingerprint recognition stage, it is necessary to control the moment when the switch transistor 1 is turned on to input a voltage signal to the shading portion 61. The shading portion 61 can be used as the gate of the switch transistor 1, so that the switch transistor 1 forms a dual-gate structure transistor, which can increase the turn-on speed of the switch transistor 1.

[0070] exist Figure 3 In the display assembly provided in the embodiment, a passivation layer 91 is provided on the first active layer 11 and the second active layer 21, and a planarization layer 93 is provided on the light shielding portion 61. The display assembly further includes a protective cover plate 92, and optionally, an anti-impact layer (not shown) is further provided on the protective cover plate 92 and the planarization layer 93.

[0071] In another embodiment, the first active layer and the second active layer are both in contact with the first insulating layer, and the second active layer and the first active layer are made of different materials, so the second active layer is sensitive to light in a different wavelength band from the first active layer. In the fingerprint recognition stage, only the first active layer is sensitive to the light emitted by the fingerprint recognition light source, and even if the fingerprint reflected light is irradiated onto the surface of the second active layer, it will not be absorbed by the second active layer and affect the switching state of the switching transistor. This implementation does not require a light shielding portion to be provided on the second active layer to shield light, which can save the process of making the light shielding portion.

[0072] In another embodiment, the second gate of the switch transistor and the first gate of the phototransistor are located in different metal layers. Figure 4 As shown, Figure 4Another schematic diagram of the partial film layer structure of the display component provided in the embodiment of the present application. The first source 13, the first drain 14, the second source 23 and the second drain 24 are all located in the first metal layer 41; the first gate 12 is located in the second metal layer 42, and the first active layer 11 and the second active layer 21 are both located on the side of the first insulating layer 51 away from the second metal layer 42, and are both in contact with the first insulating layer 51. The fingerprint recognition module 20 also includes a third metal layer 43, which is located on the side of the first metal layer 41 away from the display panel 10, and the second gate 22 is located in the third metal layer 43. An insulating layer 94 is provided on the first active layer 11 and the second active layer 21, and a planarization layer 95 is provided on the second gate 22. A protective cover plate 92 is also provided on the planarization layer 95. In this embodiment, the first active layer and the second active layer can be made of the same layer and the same material to ensure that the switching transistor and the phototransistor share part of the process and reduce the complexity of the manufacturing process. At the same time, during the fingerprint recognition stage, the second gate located on the side of the second active layer away from the display panel can be reused as a light-shielding portion. The second gate can block light to prevent the fingerprint reflected light from irradiating the surface of the second active layer, thereby increasing the carriers inside the second active layer and affecting the switching state of the switching transistor, thereby ensuring the accuracy and performance reliability of fingerprint recognition.

[0073] Continue to refer Figure 1 As shown, the first source 13 and the first gate 12 are connected through the via 511 on the first insulating layer 51. That is, the first gate 12 and the first source 13 of the phototransistor 1 are turned on, and the phototransistor 1 always works in the off state. When no light irradiates the surface of the first active layer 11, the leakage current of the phototransistor 1 is very small. However, in the fingerprint recognition stage, when the reflected light of the fingerprint irradiates the surface of the first active layer 11, the carriers generated inside the first active layer make the leakage current of the phototransistor 1 significantly larger, which can ensure that the phototransistor has a high light sensitivity.

[0074] Figure 5 A schematic diagram of a circuit structure of a fingerprint recognition unit in a display component provided in an embodiment of the present application, Figure 6 for Figure 5 The timing diagram of the fingerprint recognition circuit in the embodiment. Figure 5As shown, the fingerprint recognition module includes a fingerprint control signal line 71, a fingerprint data signal line 72 and a third voltage signal line 73; the second gate of the switch transistor 2 is electrically connected to the fingerprint control signal line 71, the second drain of the switch transistor 2 is electrically connected to the fingerprint data signal line 72, and the first gate 12 and the first source 13 are both electrically connected to the third voltage signal line 73. It should be noted that in the embodiment of the present application, the switch transistor and the phototransistor can be a p-type transistor or an n-type transistor, as long as the switch transistor and the phototransistor are of the same type.

[0075] Specifically, multiple fingerprint recognition units in the fingerprint recognition module are arranged in an array, such as Figure 7 As shown, Figure 7 A schematic diagram of a circuit structure of a fingerprint recognition module in a display component provided in an embodiment of the present application. A plurality of fingerprint recognition units 201 are arranged in an array, each fingerprint recognition unit 201 includes at least one phototransistor 1 and one switch transistor 2, the second gates of the plurality of switch transistors 2 in the same row are electrically connected to a fingerprint control signal line 71, the second drains of the plurality of switch transistors 2 in the same column are electrically connected to a fingerprint data signal line 72, and the first gates 12 and first sources 13 of the plurality of phototransistors 1 in the same row are electrically connected to a third voltage signal line 73.

[0076] In the scheme of the fingerprint recognition module composed of a switching transistor and a photodiode in the related art, the realization of the fingerprint recognition function requires the voltage signal to be respectively passed to the gate, source, drain of the switching transistor, and one of the electrodes of the photodiode, and the driving circuit is relatively complicated. In the embodiment of the present application, the fingerprint recognition function only requires the voltage signal to be passed to the second gate, the second drain of the switching transistor and the first gate (or the first source) of the phototransistor, and the driving circuit is relatively simple. In the fingerprint recognition module, only three signal lines, namely the fingerprint control signal line, the fingerprint data signal line and the third voltage signal line, need to be set, which can also simplify the wiring method in the fingerprint recognition module and save the space occupied by the wiring. Moreover, the fingerprint recognition circuit is independent of the circuit that drives the display panel display, and the fingerprint recognition detection does not need to be time-shared with the scanning time of a frame of the picture, which reduces the complexity of the circuit structure.

[0077] During the fingerprint recognition process: in the startup phase, the fingerprint control signal line 71 provides the fingerprint control signal Vscan to the switch transistor 2. In this phase, the fingerprint control signal line 71 provides a non-valid level signal to control the switch transistor 2 to turn off. The fingerprint data signal line 72 passes a reading potential to the second drain of the switch transistor 2. The first source and the first gate of the phototransistor 1 are turned on, and the bias voltage Vbias is passed through the third voltage signal line 73. The phototransistor 1 is in the off state, that is, the phototransistor 1 is in the dark state (dark). Due to the leakage current of the phototransistor 1, the first capacitor Cs begins to charge and accumulates a small amount of charge, which is recorded as the initial charge amount Q0. In the initial signal reading phase, the fingerprint control signal line 71 provides an effective level signal to the switch transistor 2. The level signal controls the switch transistor 2 to turn on, the first capacitor Cs is discharged, the fingerprint data signal line 72 reads the initial charge Q0 through the second drain 24, and then the fingerprint control signal line 71 provides a non-effective level signal to control the switch transistor 2 to turn off; in the fingerprint signal accumulation stage, after the phototransistor 1 receives the light reflected by the finger, the phototransistor 1 changes from a dark state to a bright state (illumination), and the leakage current of the phototransistor 1 increases, thereby increasing the charge accumulated by the first capacitor Cs, which is recorded as the fingerprint charge Q1; in the fingerprint signal reading stage, the fingerprint control signal line 71 provides an effective level signal to control the switch transistor 2 to turn on, then the first capacitor Cs is discharged, and the fingerprint data signal line 72 reads the fingerprint charge Q1 through the second drain 24.

[0078] Specifically, the fingerprint data signal line 72 and the second drain are located in the same metal layer, that is, the fingerprint data signal line 72 is located in the first metal layer (refer to Figure 1 The fingerprint data signal line 72 can be manufactured in the same process as the second drain, and the fingerprint data signal line 72 and the second drain do not need to be connected through the via of the insulating layer, which simplifies the process. The fingerprint control signal line 71 and the second gate are located in the same metal layer, and the fingerprint control signal line 71 and the second gate are manufactured in the same process, and the fingerprint control signal line 71 and the second gate do not need to be connected through the via of the insulating layer, which simplifies the process. In addition, the third voltage signal line 73 can be located in the same metal layer as the first gate, and can also be located in the same metal layer as the first source.

[0079] In one embodiment, the fingerprint data signal line and the second drain are located in the first metal layer, the fingerprint control signal line and the second gate are located in the third metal layer, and the third voltage signal line and the first gate are located in the second metal layer. The fingerprint data signal line, the fingerprint control signal line and the third voltage signal line are respectively wired in three different metal layers, which can reduce the wiring density in each metal layer.

[0080] In another embodiment, Figure 8Another partial film structure diagram of the display component provided in the embodiment of the present application. The display panel is an organic light emitting display panel, such as Figure 8 As shown, the display panel includes a base substrate 101, an array substrate 102, a display layer 103 and a packaging structure 104 arranged in sequence, wherein the array substrate 102 includes a gate metal layer 44, a capacitor metal layer (not shown), a source-drain metal layer 45 and a fourth metal layer 46, and an insulating layer is provided between two adjacent metal layers. The gate 66 of the driving transistor 1021 and the gate scan line 69 of the display panel (only for illustration in the figure) are located in the gate metal layer 44, the source 67 and drain 68 of the driving transistor 1021, and the data line of the display panel are located in the source-drain metal layer 45, a capacitor plate in the pixel circuit and a reset signal line in the display panel are located in the capacitor metal layer, and the positive power supply signal line in the display panel is located in the fourth metal layer 46. Optionally, the second gate 22 of the switching transistor 2 in the fingerprint recognition module 20 is connected to the gate scan line 69. The figure shows that the second gate 22 is electrically connected to the gate scan line 69 through at least one connecting electrode 461, and optionally, the connecting electrode 461 is located in the fourth metal layer 46. Among them, the second gate 22 is electrically connected to the connection electrode 461 through the via 77 that penetrates the packaging structure 104 and the display layer 103, and the connection electrode 461 is electrically connected to the gate scan line 69 through the via 78 on the insulating layer. That is, in the fingerprint recognition stage, the gate scan line 69 is multiplexed as a fingerprint control signal line, and a control signal is provided to the switch transistor 2 through the gate scan line 69. In addition, the second drain 24 of the switch transistor 2 in the fingerprint recognition module can be electrically connected to the data line located in the source and drain metal layer 45, and the data line is multiplexed as a fingerprint data signal line in the fingerprint recognition stage; the first gate 12 of the phototransistor 1 in the fingerprint recognition module can be electrically connected to the positive power supply signal line in the fourth metal layer 46, and in the fingerprint recognition stage, the positive power supply signal line is multiplexed as a third voltage signal line. In this embodiment, the wiring that drives the display panel display in the array substrate is multiplexed as a signal line in the fingerprint recognition module, and the display function and the fingerprint recognition function can be realized simultaneously through the cooperation of the display drive timing and the fingerprint recognition drive timing.

[0081] In another embodiment, the first source and the first gate are not conducting, and the phototransistor is controlled to operate in an off state by controlling the magnitude of the voltage applied to the first source and the first gate respectively during the fingerprint recognition stage. Fig. 9 A schematic diagram of another partial film layer structure of a display component provided in an embodiment of the present application. Fig.10 Fig. 9 A schematic diagram of a circuit structure of a fingerprint recognition unit in an embodiment.

[0082] like Fig. 9As shown, still taking the display panel 10 as an organic light-emitting display panel as an example, the fingerprint recognition module 20 is located on the light-emitting surface of the display panel 10. The fingerprint recognition module 20 includes a plurality of fingerprint recognition units, each of which includes at least one phototransistor 1 and one switching transistor 2. The phototransistor 1 includes a first active layer 11, a first gate 12, a first source 13 and a first drain 14. The material of the first active layer 11 includes an organic semiconductor material. The first drain 14 and the first gate 12 partially overlap to form a first capacitor Cs. The switching transistor 2 includes a second active layer 21, a second gate 22, a second source 23 and a second drain 24. The first drain 14 and the second source 23 are connected. Figure 1 The difference in the embodiment is that Fig. 9 In the embodiment, there is no conduction between the first source 13 and the first gate 12 .

[0083] like Fig.10 As shown, the fingerprint recognition module includes a fingerprint control signal line 71, a fingerprint data signal line 72, a first voltage signal line 74 and a second voltage signal line 75; the second gate is electrically connected to the fingerprint control signal line 71, the second drain is electrically connected to the fingerprint data signal line 72, the first gate is electrically connected to the first voltage signal line 74, and the first source is electrically connected to the second voltage signal line 75, wherein, in the fingerprint recognition stage, the voltage provided by the first voltage signal line 74 to the first gate is greater than the voltage provided by the second voltage signal line 75 to the first source. Thus, when the first voltage signal 74 passes a voltage signal to the first gate, and the second voltage signal 75 passes a voltage signal to the first source, the phototransistor 1 can be controlled to be in an off state.

[0084] In this embodiment, the working process of the fingerprint recognition unit can refer to the above Figure 5 and Figure 6 The embodiments are for understanding only and will not be described in detail here.

[0085] Furthermore, Fig.11 A partial top view of a display assembly provided in an embodiment of the present application is shown in FIG. Fig.11As shown, the display panel 10 includes a display area 55 and a non-display area 56, and the display area 55 includes a plurality of pixel areas 111 and a non-pixel area 121 located between adjacent pixel areas 111. The pixel area 111 is the pixel light-emitting area, and the non-pixel area 121 is the non-light-emitting area. Taking the organic light-emitting display panel as an example, the pixel area 111 is the area where the light-emitting device is located, and the non-pixel area 121 is the area where the pixel definition layer of the spaced light-emitting device is located. Taking the liquid crystal display panel as an example, the liquid crystal display panel includes a black matrix, and the black matrix includes a plurality of openings. The area exposed by the openings is the pixel area 111, and the area between adjacent openings is the non-pixel area. Among them, the positive projection of the fingerprint recognition unit 201 on the display panel 10 is located in the non-pixel area 121. The orthographic projection direction of the fingerprint recognition unit 201 onto the display panel 10 is the same as the top-view direction, so the fingerprint recognition unit 201 and the orthographic projection of the fingerprint recognition unit 201 on the display panel 10 coincide with each other in the top-view direction. In the top view, the fingerprint recognition unit 201 represents its orthographic projection on the display panel 10. Fig.11 It is only indicated that the fingerprint recognition unit 201 is set in a certain fixed area. Optionally, the fingerprint recognition unit can also be set corresponding to the entire display area. In this embodiment, the fingerprint recognition unit corresponds to the non-pixel area of ​​the display panel. When the display component is displayed, the fingerprint recognition unit will not block the light output of the pixel area, ensuring that the setting of the fingerprint recognition module does not affect the display effect.

[0086] The above embodiments are all illustrated by taking the display panel as an organic light emitting display panel, and in the display assembly provided in the embodiment of the present application, the display panel may also be a liquid crystal display panel. Fig.12 Indicated in Fig.12 Another schematic diagram of the partial film layer structure of the display component provided in the embodiment of the present application. The display panel 10 includes a base substrate 101, an array substrate 105, a liquid crystal molecule layer 106 and a color filter substrate 107 stacked in sequence. The array substrate 105 includes a plurality of pixel circuits, and the figure only schematically shows a driving transistor 1051 in the pixel circuit. The array substrate also includes a pixel electrode 1052 and a common electrode 1053. The driving transistor 1051 is connected to the pixel electrode 1052. The relative positions of the pixel electrode 1052 and the common electrode 1053 in the figure can be interchanged. The color filter substrate 107 includes a color resist layer and a black matrix. The fingerprint recognition module is located on the display panel, and the fingerprint recognition module 20 includes a fingerprint recognition unit, and the fingerprint recognition unit includes at least a phototransistor 1 and a switch transistor 2. The structure of the phototransistor 1 and the switch transistor 2 in the fingerprint recognition module can refer to the description in any of the above embodiments, and will not be repeated here.

[0087] Based on the same inventive concept, the embodiment of the present application further provides a display device, Fig.13 A schematic diagram of a display device provided in an embodiment of the present application, such as Fig.13 As shown, the display device includes the display assembly 100 provided in any embodiment of the present application. The specific structure of the display assembly 100 has been described in detail in the above embodiment and will not be repeated here. Fig.13 The display device shown is for schematic illustration only, and the display device may be any electronic device with a fingerprint recognition function, such as a mobile phone, a tablet computer, a laptop computer, an e-book, or a television. The display device may be a rigid display device or a flexible or foldable display device. In one embodiment, the pixel unit in the display panel is reused as a light source for fingerprint recognition during the fingerprint recognition stage. In another embodiment, the display device includes a fingerprint recognition light source, which is located on a side of the display panel away from the fingerprint recognition module, wherein the fingerprint recognition light source may be an infrared light source or a visible light source.

[0088] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

[0089] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A display component, characterized in that: include: A display panel and a fingerprint recognition module located on a light-emitting surface of the display panel, wherein the fingerprint recognition module includes a phototransistor and a switch transistor; The phototransistor comprises a first active layer, a first gate, a first source electrode and a first drain electrode, the material of the first active layer comprises an organic semiconductor material, and the first drain electrode and the first gate electrode form a first capacitor; The switch transistor comprises a second active layer, a second gate, a second source and a second drain; The fingerprint recognition module includes a first metal layer, wherein the first source, the first drain, the second source and the second drain are all located in the first metal layer, and the first drain is connected to the second source.

2. The display assembly according to claim 1, characterized in that The fingerprint recognition module further includes a second metal layer and a first insulating layer, wherein the second metal layer is located on a side of the first metal layer close to the display panel, and the first insulating layer is located between the first metal layer and the second metal layer; wherein The first gate is located in the second metal layer.

3. The display assembly according to claim 2, characterized in that: The first active layer and the second active layer are both located on a side of the first insulating layer away from the second metal layer, and are both in contact with the first insulating layer.

4. The display assembly according to claim 2, characterized in that: The fingerprint recognition module includes a fingerprint control signal line, a fingerprint data signal line, a first voltage signal line and a second voltage signal line; The second gate is electrically connected to the fingerprint control signal line, the second drain is electrically connected to the fingerprint data signal line, the first gate is electrically connected to the first voltage signal line, and the first source is electrically connected to the second voltage signal line, wherein, In the fingerprint recognition stage, the voltage provided by the first voltage signal line to the first gate is greater than the voltage provided by the second voltage signal line to the first source.

5. The display assembly according to claim 2, characterized in that: The first source and the first gate are connected through a via hole on the first insulating layer.

6. The display assembly according to claim 5, characterized in that: The fingerprint recognition module includes a fingerprint control signal line, a fingerprint data signal line and a third voltage signal line; The second gate is electrically connected to the fingerprint control signal line, the second drain is electrically connected to the fingerprint data signal line, and the first gate and the first source are both electrically connected to the third voltage signal line.

7. The display assembly according to claim 2, characterized in that: The second gate is located in the second metal layer.

8. The display assembly according to claim 7, characterized in that: The second active layer and the first active layer are made of the same layer and the same material.

9. The display assembly according to claim 8, characterized in that: The fingerprint recognition module further includes a plurality of light shielding portions, wherein the light shielding portions are located on a side of the second active layer away from the display panel, and the orthographic projections of the light shielding portions on the plane where the second active layer is located cover the second active layer.

10. The display assembly according to claim 1, characterized in that: The fingerprint recognition module also includes a third metal layer, which is located on a side of the first metal layer away from the display panel, and the second gate is located on the third metal layer.

11. The display assembly according to claim 1, characterized in that: The display panel includes a plurality of pixel areas and a non-pixel area located between adjacent pixel areas, wherein the fingerprint recognition module has an orthographic projection on the display panel located in the non-pixel area.

12. A display device, characterized in that: A display assembly comprising any one of claims 1 to 11.

13. A fingerprint recognition method, applicable to the display assembly according to any one of claims 1 to 11, characterized in that: The fingerprint recognition method comprises: Controlling the switch transistor and the phototransistor to be turned off, so that the leakage current of the phototransistor causes the first capacitor to be charged and accumulate an initial charge; Controlling the switch transistor to turn on, discharging the first capacitor, and controlling the switch transistor to turn off after reading the initial charge amount through the second drain; After the phototransistor receives the light reflected by the finger, the leakage current increases, and the first capacitor is charged to accumulate the fingerprint charge; The switch transistor is controlled to be turned on, the first capacitor is discharged, and the charge amount of the fingerprint is read through the second drain.

Images