Display substrate, driving method thereof and display device

Abstract

The invention provides a display substrate, a driving method thereof and a display device, belongs to the technical field of display, and can solve the problems that an existing fingerprint recognition module is large in thickness and complex in structure. The cathode layer of the display substrate disclosed by the invention is naturally broken at the edge of the isolation column to form a plurality of independent cathodes; the display substrate comprises a first control circuit and a second control circuit which are located on a substrate. The first control circuit is connected with the cathode and a second power supply signal line, and is configured to transmit a second power supply signal provided by the second power supply signal line to the cathode; the second control circuit is connected with the cathode and the sensing signal line and is configured to transmit the first reference signal or the second reference signal transmitted by the sensing signal line to the cathode or transmit a sensing signal generated between the cathode and a finger to the sensing signal line; the voltage of the first reference signal is equal to that of the second power supply signal, and the voltage of the second reference signal is not equal to that of the second power supply signal.

Description

Technical Field

[0001] The present disclosure belongs to the field of display technology, and particularly relates to a display substrate and a driving method thereof, and a display device. Background Art

[0002] With the continuous development of display technology, privacy protection has become particularly important. At present, display devices (such as mobile phones, tablets, etc.) basically use fingerprint recognition integration to complete functions such as unlocking, identity authentication, and consumer payment. Summary of the invention

[0003] The present disclosure aims to solve at least one of the technical problems existing in the prior art, and provides a display substrate and a driving method thereof, and a display device.

[0004] In a first aspect, an embodiment of the present disclosure provides a display substrate, the display substrate comprising: a base substrate, a cathode layer and an isolation column located on the base substrate; the cathode layer is naturally broken at the edge of the isolation column to form a plurality of independent cathodes; the display substrate further comprises: a first control circuit and a second control circuit located on the base substrate;

[0005] The first control circuit is connected to the cathode and the second power signal line, and is configured to transmit the second power signal provided by the second power signal line to the cathode;

[0006] The second control circuit is connected to the cathode and the sensing signal line, and is configured to transmit the first reference signal or the second reference signal transmitted by the sensing signal line to the cathode, or transmit the sensing signal generated between the cathode and the finger to the sensing signal line;

[0007] The voltage of the first reference signal is equal to the voltage of the second power signal, and the voltage of the second reference signal is not equal to the voltage of the second power signal.

[0008] In some embodiments, the second power signal line extends along a first direction, the sensing signal line extends along a second direction, and the first direction and the second direction are arranged to intersect.

[0009] In some embodiments, the display substrate further comprises: a fingerprint collection circuit and a reading chip located on the base substrate;

[0010] The fingerprint acquisition circuit is connected to the sensing signal line and the reference signal line, and is configured to acquire the sensing signal transmitted by the sensing signal line, or transmit the first reference signal or the second reference signal provided by the reference signal line to the sensing signal line;

[0011] The reading chip is configured to form a fingerprint distribution image according to the difference between the sensing signals corresponding to the valleys and the ridges to perform fingerprint recognition.

[0012] In some embodiments, the fingerprint acquisition circuit includes: an integrating amplifier, a sensing capacitor, and a switch;

[0013] The first input terminal of the integrating amplifier is connected to the reference signal line, the second input terminal is connected to the sensing signal line, and the output terminal is connected to the reading chip;

[0014] One end of the sensing capacitor is connected to the second input end of the integrating amplifier, and the other end is connected to the output end of the integrating amplifier;

[0015] One end of the switch is connected to the second input end of the integrating amplifier, and the other end of the switch is connected to the output end of the integrating amplifier.

[0016] In some embodiments, the first control circuit includes: a seventh transistor; the second control circuit includes: an eighth transistor;

[0017] The control electrode of the seventh transistor is connected to the third reset signal line, the first electrode is connected to the second power signal line, and the second electrode is connected to the cathode;

[0018] The control electrode of the eighth transistor is connected to the second scanning signal line, the first electrode is connected to the sensing signal line, and the second electrode is connected to the cathode.

[0019] In some embodiments, the display substrate further comprises: a pixel driving circuit located on the base substrate, and an anode disposed opposite to the cathode;

[0020] The pixel driving circuit is configured to provide a driving voltage to the anode in response to a first scanning signal provided by a first scanning signal line and a data signal provided by a data signal line.

[0021] In some embodiments, the pixel driving circuit includes: a first transistor, a second transistor, a third transistor, a fourth transistor, a fifth transistor, a sixth transistor and a storage capacitor;

[0022] The control electrode of the first transistor is connected to the first reset signal line, the first electrode is connected to the first initialization signal line, and the second electrode is connected to the first node;

[0023] The control electrode of the second transistor is connected to the first scanning signal line, the first electrode is connected to the data signal line, and the second electrode is connected to the first node;

[0024] The control electrode of the third transistor is connected to the first node, the first electrode is connected to the second electrode of the fifth transistor, and the second electrode is connected to the second node;

[0025] The control electrode of the fourth transistor is connected to the second reset signal line, the first electrode is connected to the second initialization signal line, and the second electrode is connected to the third node;

[0026] The control electrode of the fifth transistor is connected to the first light-emitting control signal line, the first electrode is connected to the first power signal line, and the second electrode is connected to the first electrode of the third transistor;

[0027] The control electrode of the sixth transistor is connected to the second light emitting control signal line, the first electrode is connected to the second node, and the second electrode is connected to the third node;

[0028] The anode is connected to the third node.

[0029] In some embodiments, each of the first control circuits and each of the second control circuits are connected to the same cathode; or each of the first control circuits and each of the second control circuits are connected to a plurality of adjacent cathodes.

[0030] In a second aspect, an embodiment of the present disclosure provides a display device, which includes a display substrate as provided above.

[0031] In a third aspect, an embodiment of the present disclosure provides a method for driving a display substrate, which is used to drive the display substrate provided above, wherein the driving process of the display substrate is divided into a display stage and a fingerprint recognition stage, wherein the fingerprint recognition stage includes: a reset stage and a charging collection stage; the method for driving the display substrate includes:

[0032] In the display stage, the second power signal provided by the second power signal line is transmitted to the cathode by the first control circuit, and at the same time, the first reference signal transmitted by the sensing signal line is transmitted to the cathode by the second control circuit; the voltage of the first reference signal is equal to the voltage of the second power signal;

[0033] In the reset phase, a second reference signal is transmitted to the sensing signal line, and at the same time, the second reference signal transmitted by the sensing signal line is transmitted to the cathode by using a second control circuit; the voltage of the second reference signal is not equal to the voltage of the second power supply signal;

[0034] In the charging collection stage, the second power signal transmitted by the second power signal line is transmitted to the cathode by the first control circuit, and at the same time, the sensing signal generated between the cathode and the finger is transmitted to the sensing signal line by the second control circuit.

[0035] In a fourth aspect, an embodiment of the present disclosure provides a method for driving a display substrate, which is used to drive a display substrate as provided above, wherein the driving process of the display substrate is divided into a display stage and a fingerprint recognition stage, and the fingerprint recognition stage is maintained within a multi-frame time; wherein the first frame is a reset frame, and the remaining frames are sampling frames; the fingerprint recognition stage includes: a reset stage and a charging acquisition stage; the reset stage is maintained within a reset frame time and a collection frame time, and the charging acquisition stage is maintained within a sampling frame time; the reset stage is divided into a first reset stage, a second reset stage, and a third reset stage;

[0036] In the display stage, the second power signal provided by the second power signal line is transmitted to the cathode by the first control circuit, and at the same time, the first reference signal transmitted by the sensing signal line is transmitted to the cathode by the second control circuit; the voltage of the first reference signal is equal to the voltage of the second power signal;

[0037] In a first reset phase, a second reference signal is transmitted to the sensing signal line; a voltage of the second reference signal is not equal to a voltage of the second power supply signal;

[0038] In a second reset phase, a second reference signal transmitted by the sensing signal line is transmitted to the cathode by using a second control circuit;

[0039] In a third reset phase, transmitting a second reference signal to the sensing signal line;

[0040] In the charging collection stage, the second power signal transmitted by the second power signal line is transmitted to the cathode by the first control circuit, and at the same time, the sensing signal generated between the cathode and the finger is transmitted to the sensing signal line by the second control circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 A schematic structural diagram of a display substrate provided in an embodiment of the present disclosure.

[0042] Figure 2 A schematic diagram of a circuit structure in a display substrate provided in an embodiment of the present disclosure.

[0043] Figure 3 A schematic diagram of another circuit structure in a display substrate provided in an embodiment of the present disclosure.

[0044] Figure 4 A schematic flow chart of a method for driving a display substrate provided in an embodiment of the present disclosure.

[0045] Figure 5 A timing diagram of a fingerprint recognition stage in a driving process of a display substrate provided by an embodiment of the present disclosure.

[0046] Figure 6 A schematic flow chart of another method for driving a display substrate provided in an embodiment of the present disclosure.

[0047] Figure 7 A timing diagram of a fingerprint recognition stage in a driving process of another display substrate provided by an embodiment of the present disclosure. DETAILED DESCRIPTION

[0048] In order to make the purpose, technical scheme and advantages of the embodiments of the present disclosure clearer, the technical scheme in the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings in the embodiments of the present disclosure. Obviously, the described embodiments are only part of the embodiments of the present disclosure, rather than all of the embodiments. The components of the embodiments of the present disclosure generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present disclosure provided in the drawings is not intended to limit the scope of the present disclosure for protection, but merely represents the selected embodiments of the present disclosure. Based on the embodiments of the present disclosure, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present disclosure.

[0049] Unless otherwise defined, the technical terms or scientific terms used in the present disclosure should be understood by people with ordinary skills in the field to which the present disclosure belongs. The "first", "second" and similar words used in the present disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, similar words such as "one", "one" or "the" do not indicate quantitative restrictions, but indicate that there is at least one. "Including" or "comprising" and similar words mean that the elements or objects appearing before the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects.

[0050] The "multiple or several" mentioned in this disclosure refers to two or more. "And / or" describes the association relationship of the associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the associated objects before and after are in an "or" relationship.

[0051] It should be noted that the transistors in the embodiments of the present disclosure may be thin film transistors or field effect transistors or other switching devices with the same characteristics. The thin film transistors may include oxide semiconductor thin film transistors, amorphous silicon thin film transistors or polycrystalline silicon thin film transistors, etc. The source and drain of the transistor may be symmetrical in structure, so the source and drain may be indistinguishable in physical structure. In the embodiments of the present disclosure, in order to distinguish transistors, except for the gate as the control electrode, one of the electrodes is directly described as the first electrode and the other electrode is directly described as the second electrode, so the first electrode and the second electrode of all or part of the transistors in the embodiments of the present disclosure can be interchangeable as needed.

[0052] It should be noted that the thin film transistor can be an N-type thin film transistor or a P-type thin film transistor; wherein, the N-type thin film transistor refers to the thin film transistor active layer being doped with N-type ions; and the P-type thin film transistor refers to the thin film transistor active layer being doped with P-type ions. The working level voltage of the N-type thin film transistor is a high level voltage, that is, when a high level voltage is input to the gate of the N-type thin film transistor, the source and the drain are turned on; the working level voltage of the P-type thin film transistor is a low level voltage, that is, when a low level voltage is input to the gate of the P-type thin film transistor, the source and the drain are turned on. In the description of the embodiments of the present disclosure, the N-type thin film transistor will be used as an example for explanation. It can be understood that the implementation principle of the P-type transistor is similar and will not be described in detail. The P-type transistor is also within the protection scope of the embodiments of the present disclosure.

[0053] It should also be noted that the light-emitting device in the embodiment of the present disclosure is a current-type light-emitting device, and further, it can be a light-emitting diode (Light Emitting Diode, LED), an organic light-emitting diode (Organic Light Emitting Diode, OLED), a quantum dot light-emitting diode (Quantum Dot Light Emitting Diode, QLED), a micro organic light-emitting diode (Micro Organic Light-Emitting Diode, Micro-OLED), etc. In the embodiment of the present disclosure, the light-emitting device is OLED as an example for description.

[0054] Current display devices usually use external capacitive fingerprint recognition modules, ultrasonic fingerprint recognition modules, or add under-screen integrated optical fingerprint recognition modules to achieve fingerprint recognition. In the era of full-screen products that pursue the largest screen-to-body ratio, the ability to realize fingerprint recognition at any position of the full screen is more in line with people's needs.

[0055] However, the external capacitive fingerprint recognition module and ultrasonic fingerprint recognition module will increase the thickness of the module, and the production cost of the ultrasonic fingerprint recognition module is high; the optical design of the under-screen integrated optical fingerprint recognition module is complex, and stray light affects the clarity of fingerprint imaging.

[0056] In view of this, the embodiments of the present disclosure provide a display substrate and a driving method thereof, and a display device. The display substrate and a driving method thereof, and the display device provided by the embodiments of the present disclosure will be further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0057] In a first aspect, an embodiment of the present disclosure provides a display substrate. Figure 1 A schematic diagram of the structure of a display substrate provided in an embodiment of the present disclosure is shown in FIG. Figure 2 A schematic diagram of a circuit structure in a display substrate provided in an embodiment of the present disclosure, such as Figure 1 and Figure 2 As shown, the display substrate includes: a base substrate 101, a cathode layer 102 and an isolation column 103 located on the base substrate 101; the cathode layer 102 is naturally broken at the edge of the isolation column 103 to form a plurality of independent cathodes 1020; the display substrate also includes: a first control circuit 201 and a second control circuit 202 located on the base substrate 101; the first control circuit 201 is connected to the cathode 1020 and the second power signal line VSS, and is configured to transmit the second power signal provided by the second power signal line VSS to the cathode 1020; the second control circuit 202 is connected to the cathode 1020 and the sensing signal line Sensing line, and is configured to transmit the first reference signal or the second reference signal transmitted by the sensing signal line Sensing line to the cathode 1020, or transmit the sensing signal generated between the cathode 1020 and the finger to the sensing signal line Sensing line; the voltage of the first reference signal is equal to the voltage of the second power signal, and the voltage of the second reference signal is not equal to the voltage of the second power signal.

[0058] The base substrate 101 can be made of a rigid material such as glass, which can improve the bearing capacity of the base substrate 101 for other film layers thereon. Of course, the base substrate 101 can also be made of a flexible material such as polyimide (PI), which can improve the overall bending and stretching resistance of the touch display panel, and avoid the stress generated during bending, stretching, and twisting that causes the base substrate 101 to break and cause a short circuit. In practical applications, the material of the base substrate 101 can be reasonably selected according to actual needs to ensure that the touch display panel has good performance.

[0059] A buffer layer 104 is generally provided on the substrate 101. The buffer layer 104 can be made of inorganic materials such as silicon nitride SiN, silicon oxide SiO, silicon oxynitride SiON, etc., which can prevent gases such as water and oxygen from invading from one side of the substrate 101 and avoid corrosion of other organic film layers thereon.

[0060] A driving circuit layer is disposed on the buffer layer 104, and the driving circuit layer includes a semiconductor layer 105, a first gate conductive layer 106, a second gate conductive layer 107, an interlayer dielectric layer 108, and a source-drain conductive layer 109, which are stacked in sequence in a direction away from the base substrate 101. The interlayer dielectric layer 108 is located between two adjacent conductive layers. Specifically, the interlayer dielectric layer 108 may include: a first gate insulating layer, a second gate insulating layer, and an interlayer insulating layer. The first gate insulating layer covers the semiconductor layer 105, the second gate insulating layer covers the first gate conductive layer 106, the interlayer insulating layer covers the second gate conductive layer 107, and the source-drain conductive layer 109 is located on the interlayer insulating layer.

[0061] The driving circuit layer includes a plurality of thin film transistors and storage capacitors, wherein the semiconductor layer 105 can constitute the active layer of the thin film transistor, the first gate conductive layer 106 can constitute the first gate of the thin film transistor and the first plate of the storage capacitor, the second gate conductive layer 107 can constitute the second gate of the thin film transistor and the second plate of the storage capacitor, the source-drain conductive layer 109 can constitute the source and drain of the thin film transistor, and signal wiring, such as the second power signal line VSS and the sensing signal line Sensing line. The source and drain can be connected to the two ends of the semiconductor layer 105 through the via holes of the interlayer dielectric layer 108 to transmit the corresponding signals.

[0062] A planarization layer 110 is provided on the driving circuit layer. The planarization layer 110 may be made of an organic insulating material, such as polyimide, epoxy resin, acrylic, polyester, photoresist, polyacrylate, polyamide, siloxane and other resin materials. For another example, the organic insulating material includes an elastic material, such as urethane, thermoplastic polyurethane (TPU), etc. The planarization layer 110 may planarize the source-drain conductive layer 109 to ensure that it is effectively bonded to other film layers.

[0063] An anode 111 of a light-emitting device and a pixel defining layer 112 are provided on the planarization layer 110. The anode 111 is connected to the drain electrode in the source-drain conductive layer 109 through a via hole penetrating the planarization layer 110. The pixel defining layer 112 is formed with a pixel groove, which can expose the anode 111, and an organic light-emitting layer 113 of the light-emitting device is also formed in the pixel groove. A cathode layer 102 is provided on the organic light-emitting layer 113 and the pixel defining layer 112. And an isolation column 103 is provided on the pixel defining layer 112, and the cathode layer 102 is naturally broken at the edge of the isolation column 103 to form a plurality of independent cathodes 1020. The organic light-emitting layer 113 can emit light under the drive of the electric field between the anode 111 and the cathode 102 to realize the display function. Since each cathode 1020 is independently provided, it can transmit a display signal, and can also be multiplexed as a fingerprint recognition electrode to transmit a fingerprint recognition signal.

[0064] The first control circuit 201 and the second control circuit 202 can both be formed by thin film transistors in the driving circuit layer, wherein the first control circuit 201 is connected to the cathode 1021 and the second power signal line VSS, and the second control circuit 202 is connected to the cathode 1020 and the sensing signal line Sensing line.

[0065] In the display stage, the first control circuit 201 can transmit the second power signal provided by the second power signal line VSS to the cathode 1020. The second power signal can be a low level signal, and its voltage can be 0V. At the same time, the sensing signal line Sensing line can transmit a first reference signal, and the voltage of the first reference signal is equal to the voltage of the second power signal. At this time, the second control circuit 202 can transmit the first reference signal transmitted by the sensing signal line Sensing line to the cathode 1020, playing the same role as the first control circuit 201, and realizing the display function.

[0066] During the fingerprint recognition stage, the sensing signal line Sensing line can transmit a second reference signal, and the voltage of the second reference signal is not equal to the voltage of the second power supply signal. At the same time, the cathode 1020 is multiplexed as a fingerprint recognition electrode. Due to the voltage jump, a sensing signal can be generated between the cathode 1020 and the finger. The second control circuit 202 can transmit the sensing signal to the sensing signal line Sensing line to realize the fingerprint recognition function.

[0067] In the display substrate provided by the embodiment of the present disclosure, the cathode layer 102 is naturally broken at the edge of the isolation column 103 to form a plurality of independent cathodes 1020. The independent cathodes 1020 can be reused as fingerprint recognition electrodes. Under the control of the first control circuit 201 and the second control circuit 202, the display signal (second power supply signal) can be transmitted to the cathode 1020 to realize the display function, and the sensing signal generated between the cathode 1020 and the finger is transmitted to the sensing signal line Sensing line to realize the fingerprint recognition function. In this way, the integration of the fingerprint recognition module can be realized, so that the display substrate can realize the fingerprint recognition function at any position, and there is no need to use an external fingerprint recognition module. Therefore, the thickness of the display module can be reduced, which is conducive to the thinness of the display module. At the same time, the clarity of the display screen of the display module can be improved, the user experience can be improved, and the preparation cost can be reduced.

[0068] In some embodiments, the second power signal line VSS extends along a first direction, the sensing signal line Sensing line extends along a second direction, and the first direction and the second direction are intersecting.

[0069] The second power signal line VSS can extend in the row direction, and multiple second power signal lines VSS can be arranged side by side. The sensing signal line Sensing line can extend in the column direction, and multiple sensing signal lines Sensing line can be arranged side by side, that is, the first direction is the row direction, and the second direction is the column direction. In the display stage, the second power signal line VSS and the sensing signal line Sensing line transmit signals with equal voltages. The second power signal line VSS and the sensing signal line Sensing line can form a mesh structure, which can reduce the resistance of the signal line and reduce the phenomenon of internal voltage drop (IRDrop) caused by the increase of its own resistance, thereby improving the display brightness uniformity of the display substrate. At the same time, the width of the second power signal line VSS on the periphery of the display substrate can be reduced or the second power signal line VSS on the periphery of the display substrate can be cancelled, so that a narrower frame design can be achieved, and the screen-to-body ratio of the display substrate can be increased, thereby improving the user experience.

[0070] In some embodiments, Figure 1 and Figure 2 As shown, the display substrate further includes: a fingerprint collection circuit 203 ( Figure 1 Not shown) and a read chip ( Figure 1 and Figure 2The fingerprint acquisition circuit 203 is connected to the sensing signal line Sensing line and the reference signal line Vref, and is configured to acquire the sensing signal transmitted by the sensing signal line Sensing line, or transmit the first reference signal or the second reference signal provided by the reference signal line Vref to the sensing signal line Sensing line; the reading chip is configured to form a fingerprint distribution image according to the difference between the sensing signals corresponding to the valley and the ridge, so as to perform fingerprint recognition.

[0071] Specifically, Figure 2 As shown, the fingerprint acquisition circuit 203 includes: an integrating amplifier 2031, a sensing capacitor Cf and a switch SW; the first input terminal + of the integrating amplifier 2031 is connected to the reference signal line Vref, the second input terminal - is connected to the sensing signal line Sensing line, and the output terminal Vout is connected to the reading chip; one end of the sensing capacitor Cf is connected to the second input terminal - of the integrating amplifier 2031, and the other end is connected to the output terminal Vout of the integrating amplifier 2031; one end of the switch SW is connected to the second input terminal - of the integrating amplifier 2031, and the other end is connected to the output terminal Vout of the integrating amplifier 2031.

[0072] In the display stage, the switch SW is closed, the second input terminal - and the output terminal Vout of the integrating amplifier 2031 are short-circuited, and the integrating amplifier 2031 is equivalent to a diode. At this time, the reference signal line Vref provides a first reference signal, which can be transmitted to the sensing signal line Sensing line through the integrating amplifier 2031, and then transmitted to the cathode 1020 through the sensing signal line Sensing line. The voltage of the first reference signal is equal to the voltage of the second power signal, so as to provide a display signal for the cathode 1020 to realize the display function.

[0073] In the fingerprint recognition stage, the switch SW is disconnected, and the reference signal line Vref provides a second reference signal, which can be transmitted to the sensing capacitor Cf to charge the sensing capacitor Cf. In this way, the sensing signal between the cathode 1020 and the finger can be transferred to the sensing capacitor Cf, and then transmitted to the reading chip through the output terminal Vout of the integrating amplifier 2031. The reading chip can form a fingerprint distribution image based on the difference in the sensing signals corresponding to the valley and the ridge for fingerprint recognition.

[0074] In some embodiments, Figure 1 and Figure 2As shown, the first control circuit 201 includes: a seventh transistor TFT7; the second control circuit 202 includes: an eighth transistor TFT8; the control electrode of the seventh transistor TFT7 is connected to the third reset signal line RST3, the first electrode is connected to the second power signal line VSS, and the second electrode is connected to the cathode 1020; the control electrode of the eighth transistor TFT8 is connected to the second scanning signal line GT2, the first electrode is connected to the sensing signal line Sensing line, and the second electrode is connected to the cathode 1020.

[0075] In the display stage, the seventh transistor TFT7 and the eighth transistor TFT8 are both turned on, the second power signal provided by the second power signal line can be transmitted to the cathode 1020, the second reference signal transmitted by the sensing signal line Sensing line can be transmitted to the cathode 1020, and the voltage of the second reference signal is equal to the voltage of the second power signal.

[0076] In the fingerprint recognition stage, the seventh transistor TFT7 is turned off, the eighth transistor TFT8 is turned on, and the sensing signal between the cathode 1020 and the finger can be transmitted to the sensing signal line Sensing line, and then transmitted to the reading chip through the output terminal Vout of the integrating amplifier 2031.

[0077] In some embodiments, Figure 1 and Figure 2 As shown, the display substrate also includes: a pixel driving circuit 204 located on the base substrate 101, and an anode 111 arranged opposite to the cathode 1020; the pixel driving circuit 204 is configured to provide a driving voltage to the anode 111 in response to a first scanning signal provided by the first scanning signal line GT1 and a data signal provided by the data signal line Data.

[0078] Specifically, Figure 2As shown, the pixel driving circuit 204 includes: a first transistor TFT1, a second transistor TFT2, a third transistor TFT3, a fourth transistor TFT4, a fifth transistor TFT5, a sixth transistor TFT6 and a storage capacitor Cst; the control electrode of the first transistor TFT1 is connected to the first reset signal line RST1, the first electrode is connected to the first initialization signal line Vint1, and the second electrode is connected to the first node N1; the control electrode of the second transistor TFT2 is connected to the first scanning signal line GT1, the first electrode is connected to the data signal line Data, and the second electrode is connected to the first node N1; the control electrode of the third transistor TFT3 is connected to the first node N1, the first electrode is connected to the first initialization signal line Vint1, and the second electrode is connected to the first node N1. It is connected to the second electrode of the fifth transistor TFT5, and the second electrode is connected to the second node N2; the control electrode of the fourth transistor TFT4 is connected to the second reset signal line RST2, the first electrode is connected to the second initialization signal line Vint2, and the second electrode is connected to the third node N3; the control electrode of the fifth transistor TFT5 is connected to the first light-emitting control signal line EM1, the first electrode is connected to the first power supply signal line VDD, and the second electrode is connected to the first electrode of the third transistor TFT3; the control electrode of the sixth transistor TFT6 is connected to the second light-emitting control signal line EM2, the first electrode is connected to the second node N2, and the second electrode is connected to the third node N3; the anode 111 is connected to the third node N3.

[0079] The pixel driving circuit in the embodiment of the present disclosure is described by taking the 6T1C structure as an example. The pixel driving circuit may include five switching transistors (a first transistor TFT1, a second transistor TFT2, a fourth transistor TFT4 to a sixth transistor TFT6), a driving transistor (a third transistor TFT3) and a storage capacitor Cst. The pixel driving circuit may also be a 4T2C (i.e., 4 transistors and 2 capacitors) structure, a 3T1C (i.e., 3 transistors and 1 storage capacitor) structure, a 7T1C (i.e., 7 transistors and 1 storage capacitor) structure, a 5T1C (i.e., 5 transistors and 1 storage capacitor) structure, an 8T1C (i.e., 8 transistors and 1 storage capacitor) structure or an 8T2C (i.e., 8 transistors and 2 storage capacitors) structure, etc., which is not limited in this embodiment.

[0080] In some embodiments, the driving transistor and the five switch transistors may all be N-type transistors. Using the same type of transistors in the pixel driving circuit can simplify the process flow, reduce the process difficulty of the display substrate, and improve the yield of the product.

[0081] In some embodiments, the driving transistor and the five switch transistors may be low temperature polysilicon thin film transistors, or may be oxide thin film transistors, or may be low temperature polysilicon thin film transistors and oxide thin film transistors. The active layer of the low temperature polysilicon thin film transistor is low temperature polysilicon (LTPS), and the active layer of the oxide thin film transistor is oxide semiconductor (Oxide).

[0082] Low-temperature polysilicon thin-film transistors have the advantages of high mobility and fast charging, while oxide thin-film transistors have the advantages of low leakage current. Integrating low-temperature polysilicon thin-film transistors and oxide thin-film transistors in a display substrate to form a low-temperature polycrystalline oxide (LTPO) display panel can take advantage of the advantages of both, achieve low-frequency driving, reduce power consumption, and improve display quality.

[0083] like Figure 2 As shown, each first control circuit 201 and each second control circuit 202 are connected to the same cathode 1020 . Figure 3 A schematic diagram of another circuit structure in a display substrate provided in an embodiment of the present disclosure, such as Figure 3 As shown, each first control circuit 201 and each second control circuit 202 are connected to a plurality of adjacent cathodes 1020 .

[0084] Figure 2 In the circuit structure shown, each first control circuit 201 and each second control circuit 202 are connected to the same cathode 1020, and each cathode 1020 can be used as a fingerprint recognition electrode, which can improve the accuracy of fingerprint recognition of the display substrate and improve the user experience. At the same time, the input signal of each cathode 1020 can be adjusted independently, thereby further improving the display effect.

[0085] Figure 3 In the circuit structure shown, each first control circuit 201 and each second control circuit 202 are connected to multiple adjacent cathodes 1020, for example, the cathodes 1020 of three sub-pixels in the same pixel unit, so that each three adjacent cathodes 1020 can be used as a fingerprint recognition electrode. When setting the signal routing, the number of the second power signal line VSS and the sensing signal line Sensing line can be reduced, thereby reducing the routing difficulty.

[0086] In a second aspect, an embodiment of the present disclosure provides a display device, the display device includes a display substrate as provided in any of the above embodiments, and the display device can be, for example, a mobile phone, a tablet computer, a television, a monitor, a notebook computer, a digital photo frame, a vehicle-mounted device, or any other product with a display function. Other essential components of the display device should be understood by those skilled in the art, and will not be described in detail herein, nor should they be used as a limitation to the present disclosure.

[0087] In a third aspect, an embodiment of the present disclosure provides a method for driving a display substrate, which is used to drive a display substrate as provided in any of the above embodiments. The driving process of the display substrate is divided into a display stage and a fingerprint recognition stage, wherein the fingerprint recognition stage includes: a reset stage and a charging collection stage. Figure 4 A schematic diagram of a method for driving a display substrate provided in an embodiment of the present disclosure is shown in FIG. Figure 4 As shown, the driving method of the display substrate includes the following steps S401 to S403.

[0088] Step S401, in the display stage, the second power signal provided by the second power signal line is transmitted to the cathode using the first control circuit, and at the same time, the first reference signal transmitted by the sensing signal line is transmitted to the cathode using the second control circuit; the voltage of the first reference signal is equal to the voltage of the second power signal.

[0089] In the above step S401, in the display stage, in the row direction, the third reset signal provided by the third reset signal line RST3 for each row is a high-level signal, which controls the seventh transistor TFT7 to be in a conducting state, and the second power signal line VSS is formed inside the entire display substrate and is horizontally interconnected with the cathode 1020; in the column direction, each column sensing signal line Sensing line is reset to the first reference signal provided by the reference signal line Vref by closing the switch SW, and the voltage of the first reference signal is equal to the voltage of the second power signal. The second scanning signal provided by the second scanning signal GT2 is a high-level signal, which controls the eighth transistor TFT8 to be turned on, so that the column direction sensing signal line Sensing line is interconnected with the second power signal line VSS to form a horizontal and vertical interconnected mesh connection. The first reference signal and the second power signal are both transmitted to the cathode 1020 to realize the display function.

[0090] Figure 5 The timing diagram of the fingerprint recognition stage in the driving process of a display substrate provided by the embodiment of the present disclosure is as follows. Figure 2 The circuit structure shown is used to describe in detail the fingerprint recognition stage in the display substrate driving method provided by the embodiment of the present disclosure.

[0091] Step S402, in the reset phase, the second reference signal is transmitted to the sensing signal line, and the second reference signal transmitted by the sensing signal line is transmitted to the cathode by the second control circuit; the voltage of the second reference signal is not equal to the voltage of the second power signal.

[0092] In the above step S402, at time T1, the on signal of the switch SW is a high level signal, the switch SW is closed, the second input terminal - and the output terminal Vout of the integrating amplifier 2031 are short-circuited, and the integrating amplifier 2031 is equivalent to a diode. At this time, the second scanning signal of the second scanning signal line GT2 is a high level signal, the eighth transistor TFT8 is turned on, the reference signal line Vref provides a second reference signal, the voltage of the second reference signal is not equal to the voltage of the second power supply signal, and the second reference signal can be transmitted to the sensing signal line Sensing line through the integrating amplifier 2031 and the eighth transistor TFT8, and transmitted to the cathode 1020 through the sensing signal line Sensing line, so as to reset the signal of the cathode 1020 by using the second reference signal.

[0093] Step S403, in the charging collection stage, the second power signal transmitted by the second power signal line is transmitted to the cathode by the first control circuit, and at the same time, the sensing signal generated between the cathode and the finger is transmitted to the sensing signal line by the second control circuit.

[0094] In the above step S403, at time T2, the turn-on signal of the switch SW is a low-level signal, the switch SW is disconnected, and the valley / ridge of the finger pressed on the screen forms a capacitor Cfinger at different positions on the display substrate and the independent cathode 1020 of the lower layer, as shown in the element structure of the dotted line in the figure, and then the seventh transistor TFT7 is turned on row by row through the third reset signal provided by the third reset signal line RST3, and the second power signal provided by the second power signal VSS is transmitted to the fourth node N4. At this time, the charge amount of the capacitor Cfinger increases to ΔQ=C*V=Cfinger*(VSS-Vref).

[0095] At the same time, signals are collected, and the second scanning signal provided by the second scanning signal line GT2 is a high-level signal. The eighth transistor TFT8 is turned on, and the charge of the capacitor Cfinger is transferred to the sensing capacitor Cf. The charge transfer satisfies: ΔQ=Cfinger*(VSS-Vref)=Cf*(Vref-Vout). Since the Cfinger of the fingerprint valley ridges is different, the output voltage of the output voltage Vout is different, and the morphological difference of the output voltage forms a fingerprint valley ridge distribution image; sampling ends at time T3.

[0096] In a fourth aspect, an embodiment of the present disclosure provides a method for driving a display substrate, which is used to drive a display substrate as provided in any of the above embodiments, wherein the driving process of the display substrate is divided into a display stage and a fingerprint recognition stage, and the fingerprint recognition stage is maintained within a multi-frame time; wherein the first frame is a reset frame, and the remaining frames are sampling frames; the fingerprint recognition stage includes: a reset stage and a charging and acquisition stage; the reset stage is maintained within the reset frame time and the acquisition frame time, and the charging and acquisition stage is maintained within the sampling frame time; the reset stage is divided into a first reset stage, a second reset stage, and a third reset stage. Figure 6 A schematic diagram of a process flow of another display substrate driving method provided by an embodiment of the present disclosure is shown in FIG. Figure 6 As shown, the driving method of the display substrate includes the following steps S601 to S606.

[0097] Step S601, in the display stage, the second power signal provided by the second power signal line is transmitted to the cathode using the first control circuit, and at the same time, the first reference signal transmitted by the sensing signal line is transmitted to the cathode using the second control circuit; the voltage of the first reference signal is equal to the voltage of the second power signal.

[0098] In the above step S601, in the display stage, in the row direction, the third reset signal provided by the third reset signal line RST3 for each row is a high-level signal, which controls the seventh transistor TFT7 to be in a conducting state, and the second power signal line VSS is formed inside the entire display substrate and is horizontally interconnected with the cathode 1020; in the column direction, each column sensing signal line Sensing line is reset to the first reference signal provided by the reference signal line Vref by closing the switch SW, and the voltage of the first reference signal is equal to the voltage of the second power signal. The second scanning signal provided by the second scanning signal GT2 is a high-level signal, which controls the eighth transistor TFT8 to be turned on, so that the column direction sensing signal line Sensing line is interconnected with the second power signal line VSS to form a mesh connection that is interconnected horizontally and vertically. The first reference signal and the second power signal are both transmitted to the cathode 1020 to realize the display function.

[0099] Figure 7 This is a timing diagram of the fingerprint recognition stage in the driving process of another display substrate provided by the embodiment of the present disclosure. Figure 2 The circuit structure shown is used to describe in detail the fingerprint recognition stage in the display substrate driving method provided by the embodiment of the present disclosure.

[0100] S602, in a first reset phase, transmitting a second reference signal to a sensing signal line; a voltage of the second reference signal is not equal to a voltage of the second power supply signal.

[0101] In the above step S601, the first frame is used as a reset frame, and the entire sensing signal Sensing line is reset to the second reference signal provided by the reference signal line Vref through the switch SW, and the voltage of the second reference signal is not equal to the voltage of the second power signal.

[0102] S603 , in a second reset phase, using a second control circuit to transmit a second reference signal transmitted by the sensing signal line to the cathode.

[0103] In the above step S603, the second scanning signal provided by the second scanning signal line GT2 is a high-level signal, and the eighth transistor TFT8 is turned on. This process is a pseudo sampling process, and the actual purpose is to reset the suspended fourth node N4 to the second reference signal, and scan row by row so that the fingerprint capacitor of the entire display substrate is reset to the voltage of the second reference signal.

[0104] S604, in a third reset phase, transmitting a second reference signal to a sensing signal line.

[0105] In the above step S604, at the beginning of the second frame, at time T1, the switch SW is turned on and is only responsible for resetting the voltage of the vertical sensing signal line Sensing line to the second reference signal, which is different from Figure 5 In the timing sequence shown, the voltage of the cathode 1020 is no longer reset at this time, and the reduction of the load allows the voltage of the sensing signal line Sensing line to be fully reset in a short time.

[0106] S605, in the charging collection stage, using the first control circuit to transmit the second power signal transmitted by the second power signal line to the cathode, and at the same time, using the second control circuit to transmit the sensing signal generated between the cathode and the finger to the sensing signal line.

[0107] In the above steps, at time T2, the turn-on signal of the switch SW is a low-level signal, the switch SW is disconnected, and the valley / ridge of the finger pressed on the screen forms a capacitor Cfinger at different positions on the display substrate and the independent cathode 1020 of the lower layer, as shown in the element structure of the dotted line in the figure, and then the third reset signal provided by the third reset signal line RST3 turns on the seventh transistor TFT7 row by row, and the second power signal provided by the second power signal VSS is transmitted to the fourth node N4. At this time, the charge amount of the capacitor Cfinger increases to ΔQ=C*V=Cfinger*(VSS-Vref).

[0108] At the same time, signals are collected, and the second scanning signal provided by the second scanning signal line GT2 is a high-level signal. The eighth transistor TFT8 is turned on, and the charge of the capacitor Cfinger is transferred to the sensing capacitor Cf. The charge transfer satisfies: ΔQ=Cfinger*(VSS-Vref)=Cf*(Vref-Vout). Since the Cfinger of the fingerprint valley ridges is different, the output voltage of the output voltage Vout is different, and the morphological difference of the output voltage forms a fingerprint valley ridge distribution image; sampling ends at time T3.

[0109] It should be noted that in the accompanying drawings, the sizes of layers and regions may be exaggerated for clarity of illustration. It is also understood that when an element or layer is referred to as being "on" another element or layer, it may be directly on the other element, or there may be an intermediate layer. In addition, it is understood that when an element or layer is referred to as being "under" another element or layer, it may be directly under the other element, or there may be more than one intermediate layer or element. In addition, it is also understood that when a layer or element is referred to as being "between" two layers or two elements, it may be the only layer between the two layers or two elements, or there may also be more than one intermediate layer or element. Similar reference numerals throughout the text indicate similar elements.

[0110] In the several embodiments provided in the present disclosure, it should be understood that the disclosed device can be implemented in other ways. For example, the device embodiments described above are only schematic, for example, the position of the components shown is only a logical functional position, and there may be other position arrangements in actual implementation.

[0111] It is to be understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of the present disclosure, but the present disclosure is not limited thereto. For those of ordinary skill in the art, various modifications and improvements can be made without departing from the spirit and substance of the present disclosure, and these modifications and improvements are also considered to be within the scope of protection of the present disclosure.

Claims

1. A display substrate, characterized in that: The display substrate comprises: a base substrate, a cathode layer and an isolation column located on the base substrate; the cathode layer is naturally broken at the edge of the isolation column to form a plurality of independent cathodes; the display substrate further comprises: a first control circuit and a second control circuit located on the base substrate; The first control circuit is connected to the cathode and the second power signal line, and is configured to transmit the second power signal provided by the second power signal line to the cathode; The second control circuit is connected to the cathode and the sensing signal line, and is configured to transmit the first reference signal or the second reference signal transmitted by the sensing signal line to the cathode, or transmit the sensing signal generated between the cathode and the finger to the sensing signal line; The voltage of the first reference signal is equal to the voltage of the second power signal, and the voltage of the second reference signal is not equal to the voltage of the second power signal.

2. The display substrate according to claim 1, characterized in that: The second power signal line extends along a first direction, the sensing signal line extends along a second direction, and the first direction and the second direction are arranged to intersect each other.

3. The display substrate according to claim 2, characterized in that: The display substrate further comprises: a fingerprint collection circuit and a reading chip located on the base substrate; The fingerprint acquisition circuit is connected to the sensing signal line and the reference signal line, and is configured to acquire the sensing signal transmitted by the sensing signal line, or transmit the first reference signal or the second reference signal provided by the reference signal line to the sensing signal line; The reading chip is configured to form a fingerprint distribution image according to the difference between the sensing signals corresponding to the valleys and the ridges to perform fingerprint recognition.

4. The display substrate according to claim 3, characterized in that: The fingerprint acquisition circuit comprises: an integrating amplifier, a sensing capacitor and a switch; The first input terminal of the integrating amplifier is connected to the reference signal line, the second input terminal is connected to the sensing signal line, and the output terminal is connected to the reading chip; One end of the sensing capacitor is connected to the second input end of the integrating amplifier, and the other end is connected to the output end of the integrating amplifier; One end of the switch is connected to the second input end of the integrating amplifier, and the other end of the switch is connected to the output end of the integrating amplifier.

5. The display substrate according to claim 1, characterized in that: The first control circuit includes: a seventh transistor; the second control circuit includes: an eighth transistor; The control electrode of the seventh transistor is connected to the third reset signal line, the first electrode is connected to the second power signal line, and the second electrode is connected to the cathode; The control electrode of the eighth transistor is connected to the second scanning signal line, the first electrode is connected to the sensing signal line, and the second electrode is connected to the cathode.

6. The display substrate according to claim 1, characterized in that: The display substrate further comprises: a pixel driving circuit located on the base substrate, and an anode arranged opposite to the cathode; The pixel driving circuit is configured to provide a driving voltage to the anode in response to a first scanning signal provided by a first scanning signal line and a data signal provided by a data signal line.

7. The display substrate according to claim 6, characterized in that: The pixel driving circuit comprises: a first transistor, a second transistor, a third transistor, a fourth transistor, a fifth transistor, a sixth transistor and a storage capacitor; The control electrode of the first transistor is connected to the first reset signal line, the first electrode is connected to the first initialization signal line, and the second electrode is connected to the first node; The control electrode of the second transistor is connected to the first scanning signal line, the first electrode is connected to the data signal line, and the second electrode is connected to the first node; The control electrode of the third transistor is connected to the first node, the first electrode is connected to the second electrode of the fifth transistor, and the second electrode is connected to the second node; The control electrode of the fourth transistor is connected to the second reset signal line, the first electrode is connected to the second initialization signal line, and the second electrode is connected to the third node; The control electrode of the fifth transistor is connected to the first light-emitting control signal line, the first electrode is connected to the first power signal line, and the second electrode is connected to the first electrode of the third transistor; The control electrode of the sixth transistor is connected to the second light emitting control signal line, the first electrode is connected to the second node, and the second electrode is connected to the third node; The anode is connected to the third node.

8. The display substrate according to claim 1, characterized in that: Each of the first control circuits and each of the second control circuits are connected to the same cathode; or each of the first control circuits and each of the second control circuits are connected to a plurality of adjacent cathodes.

9. A display device, characterized in that: The display device comprises the display substrate according to any one of claims 1 to 8.

10. A method for driving a display substrate, for driving the display substrate according to any one of claims 1 to 8, characterized in that: The driving process of the display substrate is divided into a display stage and a fingerprint recognition stage, wherein the fingerprint recognition stage includes: a reset stage and a charging collection stage; the driving method of the display substrate includes: In the display stage, the second power signal provided by the second power signal line is transmitted to the cathode by the first control circuit, and at the same time, the first reference signal transmitted by the sensing signal line is transmitted to the cathode by the second control circuit; the voltage of the first reference signal is equal to the voltage of the second power signal; In the reset phase, a second reference signal is transmitted to the sensing signal line, and at the same time, the second reference signal transmitted by the sensing signal line is transmitted to the cathode by using a second control circuit; the voltage of the second reference signal is not equal to the voltage of the second power supply signal; In the charging collection stage, the second power signal transmitted by the second power signal line is transmitted to the cathode by the first control circuit, and at the same time, the sensing signal generated between the cathode and the finger is transmitted to the sensing signal line by the second control circuit.

11. A method for driving a display substrate, for driving the display substrate according to any one of claims 1 to 8, characterized in that: The driving process of the display substrate is divided into a display stage and a fingerprint recognition stage, and the fingerprint recognition stage is maintained within a multi-frame time; wherein the first frame is a reset frame, and the remaining frames are sampling frames; the fingerprint recognition stage includes: a reset stage and a charging acquisition stage; the reset stage is maintained within the reset frame time and the acquisition frame time, and the charging acquisition stage is maintained within the sampling frame time; the reset stage is divided into a first reset stage, a second reset stage, and a third reset stage; In the display stage, the second power signal provided by the second power signal line is transmitted to the cathode by the first control circuit, and at the same time, the first reference signal transmitted by the sensing signal line is transmitted to the cathode by the second control circuit; the voltage of the first reference signal is equal to the voltage of the second power signal; In a first reset phase, a second reference signal is transmitted to the sensing signal line; a voltage of the second reference signal is not equal to a voltage of the second power supply signal; In a second reset phase, a second reference signal transmitted by the sensing signal line is transmitted to the cathode by using a second control circuit; In a third reset phase, transmitting a second reference signal to the sensing signal line; In the charging collection stage, the second power signal transmitted by the second power signal line is transmitted to the cathode by the first control circuit, and at the same time, the sensing signal generated between the cathode and the finger is transmitted to the sensing signal line by the second control circuit.

Images