Foldable display panel and display device

Abstract

The invention discloses a foldable display panel and a display device. The foldable display panel comprises at least one bending area and a plurality of non-bending areas, and one bending area is located between every two adjacent non-bending areas. The bending area is configured to be switched between a folded state and a flattened state; the foldable display panel comprises a flexible display module and an electro-osmotic pump structure layer which are arranged in a stacked mode, and parts of the flexible display module and the electro-osmotic pump structure layer are both located in the bending area; the electro-osmotic pump structure layer is configured to adjust the flatness of the flexible display module located in the bending area when the bending area is in the flattened state, and the flatness of the flexible display module can be improved.

Description

Technical Field

[0001] This disclosure relates to, but is not limited to, the field of display technologies, and more particularly to a foldable display panel and a display device. Background Art

[0002] Organic Light Emitting Diode (OLED) and Quantum-dot Light Emitting Diodes (QLED) are active light-emitting display devices, which have the advantages of self-luminescence, wide viewing angle, high contrast ratio, low power consumption, extremely high response speed, thinness, flexibility, and low cost. With the continuous development of display technologies, flexible display devices (Flexible Display) using OLED or QLED as light-emitting devices and controlled by Thin Film Transistors (TFT) have become the mainstream products in the current display field.

[0003] However, currently, there are situations where the reflected images on the screen surface of flexible display devices are distorted and deformed, resulting in a decline in the user experience. Summary of the Invention

[0004] Embodiments of the present disclosure provide a foldable display panel and a display device, which can solve the problem of poor flatness in the bending area of the existing foldable display panel.

[0005] On the one hand, embodiments of the present disclosure provide a foldable display panel, including at least one bending area and a plurality of non-bending areas, and one of the bending areas is located between two adjacent non-bending areas; the bending area is configured to be switchable between a folded state and a flattened state;

[0006] The foldable display panel includes a flexible display module and an electroosmotic pump structure layer stacked, and parts of the flexible display module and the electroosmotic pump structure layer are both located in the bending area; the electroosmotic pump structure layer is configured to adjust the flatness of the flexible display module located in the bending area when the bending area is in the flattened state.

[0007] In an exemplary embodiment, the electroosmotic pump structure layer includes a substrate, a second electrode layer, a porous dielectric film, a first electrode layer, and a flexible layer stacked in sequence; the flexible layer is closer to the flexible display module than the substrate, and at least part of the flexible layer is located in the bending area; the porous dielectric film has a plurality of microchannels, the microchannels are filled with an electrolyte, and the porous dielectric film and the electrolyte form an electric double layer;

[0008] The first electrode layer and the second electrode layer are configured to form an electric field to drive the movement of ions in the double electric layer, so that the flexible layer deforms.

[0009] In an exemplary embodiment, the foldable display panel further includes a detection component and a control chip, and the detection component and the electroosmotic pump structure layer are both electrically connected to the control chip, and the detection component is located in the bending area; the detection component includes at least one sensor, and the sensor is configured to detect the strain of the flexible display module in the flattening state and located in the bending area, and transmit the detected strain to the control chip;

[0010] The control chip is configured to control the amount of deformation of the flexible layer according to the received strain.

[0011] In an exemplary embodiment, the control chip is configured to control the electric field formed by the second electrode layer and the first electrode layer according to the received strain, so as to control the amount of deformation of the flexible layer.

[0012] In an exemplary embodiment, at least one of the second electrode layer and the first electrode layer includes a plurality of electrodes arranged at intervals.

[0013] In an exemplary embodiment, the range of the amount of deformation is 0.1 mm to 0.2 mm.

[0014] In an exemplary embodiment, the detection component is located on a side of the flexible display module away from the electroosmotic pump structure layer; or at least a part of the detection component is embedded in the flexible display module.

[0015] In an exemplary embodiment, in a plane perpendicular to the plane where the foldable display panel is located, in the structure where the flexible layer is deformed, the shape of the surface of the flexible layer on the side away from the substrate includes at least one of a circular arc shape and a wavy shape.

[0016] In an exemplary embodiment, the thickness range of the electroosmotic pump structure layer is 0.25 mm to 0.5 mm.

[0017] On the other hand, an embodiment of the present disclosure provides a display device, including the foldable display panel according to any one of the foregoing embodiments.

[0018] Other features and advantages of the present application will be described in the subsequent specification, and some of them will become obvious from the specification, or be understood by implementing the present application. Other advantages of the present application can be realized and obtained by the solutions described in the specification and the drawings. Description of the Drawings

[0019] The accompanying drawings are used to provide an understanding of the technical solution of the present application, and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the technical solution of the present application, and do not constitute a limitation on the technical solution of the present application.

[0020] Figure 1 It is a schematic cross-sectional structure diagram of a foldable display device;

[0021] Figure 2A It is a schematic structural diagram of a foldable display device in a folded state;

[0022] Figure 2B It is a schematic structural diagram of a foldable display device in a flattened state;

[0023] Figure 3A It is a schematic structural diagram of another foldable display device in a folded state;

[0024] Figure 3B It is a schematic structural diagram of another foldable display device in a flattened state;

[0025] Figure 4 It is a schematic cross-sectional structure diagram of a foldable display panel according to an embodiment of the present disclosure;

[0026] Figure 5A It is a schematic cross-sectional structure diagram of an electroosmotic pump structure layer according to an embodiment of the present disclosure;

[0027] Figure 5B It is a schematic circuit principle diagram of an electroosmotic pump structure layer according to an embodiment of the present disclosure;

[0028] Figure 6A It is a schematic structural diagram of a foldable display panel according to an embodiment of the present disclosure in a folded state;

[0029] Figure 6B It is a schematic structural diagram of a foldable display panel according to an embodiment of the present disclosure in a flattened state;

[0030] Figure 7A It is a schematic structural diagram of a foldable display panel according to another embodiment of the present disclosure in a folded state;

[0031] Figure 7B It is a schematic structural diagram of a foldable display panel according to another embodiment of the present disclosure in a flattened state;

[0032] Figure 8A It is a schematic diagram of the deformation of the flexible layer of the electroosmotic pump structure layer according to an embodiment of the present disclosure;

[0033] Figure 8B It is a schematic diagram of the deformation of the flexible layer of the electroosmotic pump structure layer according to another embodiment of the present disclosure;

[0034] Figure 8C Schematic diagram of deformation of the flexible layer of the electroosmotic pump structure layer according to another embodiment of the present disclosure. Detailed implementation manners

[0035] To make the objectives, technical solutions and advantages of the present disclosure clearer and more understandable, the embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. The implementation manners can be implemented in multiple different forms. It is easy for those of ordinary skill in the art to understand a fact that the manners and contents can be transformed into one or more forms without departing from the gist and scope of the present disclosure. Therefore, the present disclosure should not be construed as being limited only to the contents described in the following implementation manners. Without conflict, the embodiments and features in the embodiments of the present disclosure can be combined with each other arbitrarily.

[0036] In the drawings, sometimes for clarity, the sizes, thicknesses of layers or regions of one or more constituent elements are exaggerated. Therefore, one manner of the present disclosure is not necessarily limited to such dimensions, and the shapes and sizes of the components in the drawings do not reflect the true proportions. In addition, the drawings schematically show ideal examples, and one manner of the present disclosure is not limited to the shapes or numerical values shown in the drawings.

[0037] The ordinal numbers such as "first", "second", "third", etc. in the present disclosure are set to avoid confusion of constituent elements, rather than to limit in terms of quantity. "Multiple" in the present disclosure includes two and more than two quantities.

[0038] In the present disclosure, for convenience, terms indicating orientation or positional relationships such as "middle", "upper", "lower", "front", "rear", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. are used to describe the positional relationships of the constituent elements with reference to the drawings, which are only for facilitating the description of this specification and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and thus cannot be construed as a limitation to the present disclosure. The positional relationships of the constituent elements are appropriately changed according to the directions for describing the constituent elements. Therefore, it is not limited to the terms described in the specification and can be appropriately replaced according to the situation.

[0039] In the present disclosure, unless otherwise clearly specified and limited, the terms "installed", "connected", "coupled" shall be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection; it can be directly connected, or indirectly connected through an intermediate member, or the internal communication of two elements. For those of ordinary skill in the art, the meanings of the above terms in the present disclosure can be understood according to the circumstances.

[0040] In the present disclosure, a transistor refers to an element including at least three terminals: a gate electrode, a drain electrode, and a source electrode. The transistor has a channel region between the drain electrode (drain electrode terminal, drain region, or drain) and the source electrode (source electrode terminal, source region, or source), and current can flow through the drain electrode, the channel region, and the source electrode. In the present disclosure, the channel region refers to the region through which current mainly flows.

[0041] In the present disclosure, the first pole can be the drain electrode and the second pole can be the source electrode, or the first pole can be the source electrode and the second pole can be the drain electrode. In cases where transistors with opposite polarities are used or the direction of current changes during circuit operation, etc., the functions of the "source electrode" and "drain electrode" sometimes switch with each other. Therefore, in the present disclosure, the "source electrode" and "drain electrode" can be switched with each other.

[0042] In the present disclosure, "electrically connected" includes cases where components are connected together through an element having a certain electrical effect. There are no particular limitations on the "element having a certain electrical effect" as long as it can transmit electrical signals between the components to be connected. Examples of the "element having a certain electrical effect" include not only electrodes and wirings, but also switching elements such as transistors, resistors, inductors, capacitors, and other elements having one or more functions.

[0043] In the present disclosure, "parallel" refers to a state where the angle formed by two straight lines is -10° or more and 10° or less, and thus, it can include a state where the angle is -5° or more and 5° or less. In addition, "perpendicular" refers to a state where the angle formed by two straight lines is 80° or more and 100° or less, and thus, it can include a state where the angle is 85° or more and 95° or less.

[0044] In the present disclosure, "film" and "layer" can be switched with each other. For example, sometimes the "conductive layer" can be changed to the "conductive film". Similarly, sometimes the "insulating film" can be changed to the "insulating layer".

[0045] "About" in the present disclosure means that the boundary is not strictly defined and allows values within the range of process and measurement errors.

[0046] Figure 1 It is a schematic cross-sectional structure diagram of a foldable display device. As Figure 1 shown, the foldable display device 100 may include a first non-bending region 101, a bending region 103, and a second non-bending region 102 arranged in sequence. Both the first non-bending region 101 and the second non-bending region 102 include a display region, and the display region can be used to display still or dynamic images, etc. The foldable display device 100 can be bent via the bending region 103.

[0047] Figure 2ASchematic structural diagram of a foldable display device in a folded state Figure 2B Schematic structural diagram of a foldable display device in a flattened state Figure 3A Schematic structural diagram of another foldable display device in a folded state Figure 3B Schematic structural diagram of another foldable display device in a flattened state. As Figure 2A , Figure 2B , Figure 3A and Figure 3B shown, the bending region 103 can be switched between a folded state and a flattened state, so that the foldable display device 100 can be switched between a folded state and a flattened state. That is, when the bending region 103 is in the folded state, the foldable display device 100 is in the folded state, and when the bending region 103 is in the flattened state, the foldable display device 100 is in the flattened state.

[0048] As Figure 2B , Figure 3B shown, after the foldable display device 100 is folded multiple times, different degrees of wrinkles will appear in the bending region 103, as shown in the dashed boxes in Figure 2B , Figure 3B . As a result, when the display device displays an image, partial image distortion will occur. Even when the display device is in the off-screen state, due to the unevenness of the bending region, the reflected image on the surface of the bending region will also be distorted and deformed, affecting the product quality and causing a decline in the user experience.

[0049] Therefore, an embodiment of the present disclosure provides a foldable display panel, including at least one bending region and a plurality of non-bending regions, and one of the bending regions is located between two adjacent non-bending regions; the bending region is configured to be switchable between a folded state and a flattened state;

[0050] The foldable display panel includes a flexible display module and an electroosmotic pump structure layer arranged in a stacked manner, and parts of the flexible display module and the electroosmotic pump structure layer are both located in the bending region; the electroosmotic pump structure layer is configured to adjust the flatness of the flexible display module located in the bending region when the bending region is in the flattened state.

[0051] In the embodiment of the present disclosure, by providing an electroosmotic pump structure layer and configuring the electroosmotic pump structure layer to adjust the flatness of the flexible display module located in the bending region when the bending region is in the flattened state, the flatness of the flexible display module can be improved, the display quality of the foldable display panel can be improved, and the user experience can be enhanced.

[0052] Figure 4 Schematic cross-sectional structure diagram of a foldable display panel according to an embodiment of the present disclosure. As Figure 4As shown in the figure, in the direction perpendicular to the plane where the foldable display panel 200 is located, the foldable display panel 200 may include a flexible display module 201, an adhesive layer 202, a support layer 203, and an electroosmotic pump structure layer 204 that are sequentially stacked. The foldable display panel 200 may include a display side and a non-display side that are oppositely arranged. Among them, the display side may be the side where the foldable display panel 200 can display an image. When a human eye is on the display side, the image displayed by the foldable display panel 200 can be viewed. The flexible display module 201 is closer to the display side than the electroosmotic pump structure layer 204. The foldable display panel 200 may further include other film layers, such as a touch control structure layer, etc., which are not limited in this disclosure. In some examples, the electroosmotic pump structure layer 204 may be in contact with the side of the flexible display module 201 away from the display side.

[0053] As Figure 4 shown, the foldable display panel 200 may include at least one bending area BB and a plurality of non-bending areas, and one bending area BB may be located between two adjacent non-bending areas. For example, the foldable display panel 200 may include one bending area BB and two non-bending areas, or the foldable display panel 200 may include two bending areas BB and three non-bending areas, etc. The number, division method, and positional relationship of the bending area and the non-bending area may be determined according to actual needs, which are not limited in this disclosure. In the embodiment of this disclosure, taking the foldable display panel 200 including one bending area BB and two non-bending areas as an example, the two non-bending areas are respectively the first non-bending area AA1 and the second non-bending area AA2, and the first non-bending area AA1 and the second non-bending area AA2 are respectively located on both sides of the bending area BB. In the embodiment of this disclosure, the bending area BB may be switched between a folded state and a flattened state, so that the foldable display panel 200 can be switched between a folded state and a flattened state, that is, when the bending area BB is in the folded state, the foldable display panel 200 is in the folded state, and when the bending area BB is in the flattened state, the foldable display panel 200 is in the flattened state. In the embodiment of this disclosure, the bending area refers to the area that needs to be bent when the foldable display panel is bent, and the non-bending area refers to the area that does not bend or bends less when the foldable display panel is bent.

[0054] As Figure 4As shown, at least a part of the electroosmotic pump structure layer 204 is located in the bending region BB. At least one bending region BB and the projection of the electroosmotic pump structure layer 204 on the plane where the foldable display panel 200 is located overlap at least partially. For example, the projection of the electroosmotic pump structure layer 204 on the plane where the foldable display panel 200 is located includes the projection of one bending region BB on the plane where the foldable display panel 200 is located, or the projection of the electroosmotic pump structure layer 204 on the plane where the foldable display panel 200 is located includes the projection of one bending region BB on the plane where the foldable display panel 200 is located, and the projection of the electroosmotic pump structure layer 204 on the plane where the foldable display panel 200 is located and the projection of at least one non-bending region on the plane where the foldable display panel 200 is located overlap at least partially, or the projection of the electroosmotic pump structure layer 204 on the plane where the foldable display panel 200 is located includes the projections of all bending regions BB on the plane where the foldable display panel 200 is located. In the embodiments of the present disclosure, the electroosmotic pump structure layer 204 is configured to apply a force to the flexible display module 201 located in the bending region BB to adjust the flatness of the flexible display module 201 located in the bending region BB.

[0055] In an exemplary embodiment, the bending region BB may include a first edge region BB1, a middle region BB3, and a second edge region BB2 arranged in sequence. The first edge region BB1 is closer to the first non-bending region AA1 than the second edge region BB2, and the second edge region BB2 is closer to the second non-bending region AA2 than the first edge region BB1. The bending region BB is in a folded state, and the deformation of the middle region BB3 is greater than that of the first edge region BB1 and the second edge region BB2. Therefore, when the bending region BB is in a flattened state, the flatness of the middle region BB3 is worse than that of the first edge region BB1 and the second edge region BB2, and thus more adjustment is needed. The projection of the electroosmotic pump structure layer 204 on the plane where the foldable display panel 200 is located and the projection of at least one middle region BB3 on the plane where the foldable display panel 200 is located overlap at least partially. For example, the projection of the electroosmotic pump structure layer 204 on the plane where the foldable display panel 200 is located includes the projection of at least one middle region BB3 on the plane where the foldable display panel 200 is located. With such a design, the setting area of the electroosmotic pump structure layer 204 can be reduced, and the cost of the foldable display panel 200 can be lowered.

[0056] In an exemplary embodiment, along the direction of the first non-bending region AA1 towards the second non-bending region AA2, the bending region BB can be evenly divided into three equal parts, and the first edge region BB1, the middle region BB3, and the second edge region BB2 can each account for one-third of them. Alternatively, the bending region BB can be evenly divided into four equal parts, the first edge region BB1 and the second edge region BB2 can each account for one-fourth of them, and the middle region BB3 accounts for two-fourths of them. Alternatively, the bending region BB can be evenly divided into five equal parts, the first edge region BB1 and the second edge region BB2 can each account for one-fifth of them, and the middle region BB3 accounts for three-fifths of them, etc.

[0057] In an exemplary embodiment, the first non-bending region AA1 can include a first display region and a first peripheral region located on at least one side of the first display region. The second non-bending region AA2 can include a second display region and a second peripheral region located on at least one side of the second display region. Exemplarily, the orthographic projections of the first non-bending region AA1 and the second non-bending region AA2 on the plane where the foldable display panel 200 is located can both be rectangles.

[0058] In an exemplary embodiment, the flexible display module 201 located in the first display region can include a display structure layer. The display structure layer can include a plurality of pixel units (each pixel unit includes a plurality of sub-pixels), a plurality of scan signal lines, and a plurality of data signal lines. The plurality of data signal lines can extend along a first direction, and the plurality of scan signal lines can extend along a second direction. The orthographic projections of the plurality of scan signal lines and the plurality of data signal lines on the support layer 203 can intersect to form a plurality of sub-pixel regions. One sub-pixel is disposed in one sub-pixel region. The plurality of data signal lines are electrically connected to the plurality of sub-pixels, and the plurality of data signal lines are configured to provide data signals to the plurality of sub-pixels. The plurality of scan signal lines are electrically connected to the plurality of sub-pixels, and the plurality of scan signal lines are configured to provide gate drive signals to the plurality of sub-pixels. The first direction intersects with the second direction, and the plane formed thereby is parallel to the plane where the foldable display panel 200 is located.

[0059] In an exemplary embodiment, one pixel unit can include at least three sub-pixels, which are a red sub-pixel, a green sub-pixel, and a blue sub-pixel respectively. The three sub-pixels can be arranged in a horizontal side-by-side, vertical side-by-side, or triangular arrangement, and the present disclosure does not limit this. Exemplarily, one pixel unit can include four sub-pixels, which are a red sub-pixel, a green sub-pixel, a blue sub-pixel, and a white sub-pixel respectively. The four sub-pixels can be arranged in a horizontal side-by-side, vertical side-by-side, or square arrangement.

[0060] In an exemplary embodiment, at least one sub-pixel may include a pixel driving circuit and a light-emitting element. The pixel driving circuit may be configured to drive the electrically connected light-emitting element. For example, the pixel driving circuit may include a plurality of transistors and at least one capacitor. By way of example, the pixel driving circuit may be a 3T1C, 4T1C, 5T1C, 5T2C, 6T1C, 7T1C or 8T1C structure. Herein, T in the above circuit structures refers to a transistor, C refers to a capacitor, the number before T represents the number of transistors in the circuit, and the number before C represents the number of capacitors in the circuit.

[0061] In an exemplary embodiment, the plurality of transistors in the pixel driving circuit may be P-type transistors, or may be N-type transistors. Using transistors of the same type in the pixel driving circuit can simplify the process flow, reduce the process difficulty of the foldable display panel, and improve the yield of the product. In some other examples, the plurality of transistors in the pixel driving circuit may include P-type transistors and N-type transistors.

[0062] In an exemplary embodiment, the plurality of transistors in the pixel driving circuit may employ low-temperature polysilicon thin-film transistors, or may employ oxide thin-film transistors, or may employ low-temperature polysilicon thin-film transistors and oxide thin-film transistors. The active layer of the low-temperature polysilicon thin-film transistor uses low-temperature polysilicon (LTPS, Low Temperature Poly-Silicon), and the active layer of the oxide thin-film transistor uses an oxide semiconductor (Oxide). The low-temperature polysilicon thin-film transistor has advantages such as high mobility and fast charging, and the oxide thin-film transistor has advantages such as low leakage current. Integrating the low-temperature polysilicon thin-film transistor and the oxide thin-film transistor on a foldable display panel, that is, an LTPS+Oxide (abbreviated as LTPO) display panel, can utilize the advantages of both, can achieve low-frequency driving, can reduce power consumption, and can improve the display quality.

[0063] In an exemplary embodiment, the light-emitting element may be any one of a light-emitting diode (LED), an organic light-emitting diode (OLED), a quantum dot light-emitting diode (QLED), a micro-LED (including: mini-LED or micro-LED), etc. For example, the light-emitting element may be an OLED, and the light-emitting element can emit red light, green light, blue light, white light, etc. under the drive of its corresponding pixel driving circuit. The color of the light emitted by the light-emitting element can be determined as needed. In some examples, the light-emitting element may include an anode, a cathode, and an organic light-emitting layer located between the anode and the cathode. The anode of the light-emitting element may be electrically connected to the corresponding pixel driving circuit, and the present disclosure does not limit this.

[0064] In an exemplary embodiment, the flexible display module 201 located in the first peripheral area may include a bonding circuit for connecting signal lines to an external driving device. For example, the bonding circuit may be electrically connected to the external driving device via a chip on film. The first peripheral area may further include a gate driving circuit, a power supply line for transmitting voltage signals to a plurality of sub-pixels, etc. The second peripheral area may be designed with reference to the first peripheral area, and the second display area may be designed with reference to the first display area, which will not be elaborated here.

[0065] In an exemplary embodiment, the adhesive layer 202 may be an optical adhesive layer, and the material of the optical adhesive layer includes optically clear adhesive (OCA). The optical adhesive has advantages such as high cleanliness, high light transmittance, low haze, high adhesion, no crystal points, no bubbles, water resistance, high temperature resistance, ultraviolet resistance, etc., and has a relatively high thickness uniformity and flatness.

[0066] In an exemplary embodiment, the support layer 203 may include a first flexible material layer, a first inorganic material layer, a second flexible material layer, and a second inorganic material layer stacked. Among them, the materials of the first flexible material layer and the second flexible material layer may be polyimide (PI), polyethylene terephthalate (PET), or a surface-treated polymer soft film, etc., and the materials of the first inorganic material layer and the second inorganic material layer may be silicon nitride (SiNx) or silicon oxide (SiOx), etc., which can improve the water and oxygen resistance of the support layer 203. The present disclosure does not limit this.

[0067] Figure 5A It is a schematic cross-sectional structure diagram of an electroosmotic pump structure layer according to an embodiment of the present disclosure. Figure 5B It is a schematic circuit principle diagram of an electroosmotic pump structure layer according to an embodiment of the present disclosure. As Figure 5A 、 Figure 5BAs shown, the electroosmotic pump structure layer 204 may include a substrate 204-5, a second electrode layer 204-2, a porous medium membrane 204-4, a first electrode layer 204-1, and a flexible layer 204-3 that are sequentially stacked. The flexible layer 204-3 is closer to the display side than the substrate 204-5. The porous medium membrane 204-4 may have a plurality of microchannels, and the microchannels are filled with an electrolyte. The surface of the porous medium membrane 204-4 is charged (for example, negatively charged), forming an electric double layer (EDL) with the electrolyte. Both the first electrode layer 204-1 and the second electrode layer 204-2 include a plurality of electrodes. The plurality of electrodes can form an electric field, and the electric field can drive the movement of ions in the electric double layer to drive the movement of the electrolyte, thereby forming an electroosmotic flow, as shown by the dotted arrow lines in Figure 5B . The electroosmotic flow will push the electrolyte to gather in the direction of the flexible layer 204-3, thereby generating a force to deform the flexible layer 204-3. The deformed flexible layer 204-3 will transfer the force to the flexible display module 201 located in the bending area BB, so that the electroosmotic pump structure layer 204 can be used to adjust the flatness of the flexible display module 201 located in the bending area BB. Exemplarily, a part of the flexible layer 204-3 can protrude towards the flexible display module 201 to apply a force to the flexible display module 201 to achieve the adjustment of the flatness of the flexible display module 201.

[0068] In an exemplary embodiment, the material of the substrate 204-5 can be polyimide (PI) or polyethylene terephthalate (PET), etc. The substrate 204-5 can be a single-layer structure, or can be a laminated structure composed of an inorganic material layer and a flexible material layer. The present disclosure does not limit this here.

[0069] In an exemplary embodiment, the material of the first electrode layer 204-1 may include an inert metal, such as platinum (Pt) or gold (Au), etc. Using an inert metal can avoid the corrosion of the electrolyte and improve the service life of the first electrode layer 204-1. Alternatively, the material of the first electrode layer 204-1 can be a transparent conductive material, such as indium tin oxide (ITO) or indium zinc oxide (IZO). Using a transparent conductive material can facilitate the integration of the electroosmotic pump structure layer 204 with other components. The structure and material of the second electrode layer 204-2 can be designed with reference to the first electrode layer 204-1.

[0070] In an exemplary embodiment, at least one of the first electrode layer 204-1 and the second electrode layer 204-2 may include a plurality of electrodes arranged at intervals to achieve zonal control of the flexible layer 204-3, which can improve the flexibility and accuracy of the adjustment of the electroosmotic pump structure layer 204. For example, the first electrode layer 204-1 may include a plurality of electrodes arranged at intervals, and the second electrode layer 204-2 may be a planar electrode. For example, the second electrode layer 204-2 may be grounded. Alternatively, the second electrode layer 204-2 may include a plurality of electrodes arranged at intervals, and the first electrode layer 204-1 may be a planar electrode.

[0071] In an exemplary embodiment, the thickness range of the first electrode layer 204-1 may be from 100 nanometers to 300 nanometers.

[0072] In an exemplary embodiment, the porous medium film 204-4 may be a polyimide (PI)-based porous film, a porous polydimethylsiloxane (PDMS) film, a transparent nanocellulose film, a porous alumina film, a glass fiber porous film, or the like.

[0073] In an exemplary embodiment, the material of the flexible layer 204-3 may include an elastic polymer, such as polydimethylsiloxane (PDMS) or polyurethane. The thickness range of the flexible layer 204-3 may be from 50 micrometers to 200 micrometers.

[0074] In an exemplary embodiment, the flexible layer 204-3 may be pre-stretched to avoid problems such as wrinkling when the flexible layer 204-3 deforms, which is beneficial to adjusting the flatness of the flexible display module 201 located in the bending area BB and can improve the accuracy of the adjustment.

[0075] In an exemplary embodiment, the thickness range of the electroosmotic pump structure layer 204 may be from 0.25 millimeters to 0.5 millimeters, which is beneficial to the thin and light design of the foldable display panel.

[0076] In an exemplary embodiment, the deformation amount range of the flexible layer 204-3 when deforming may be from 0.1 millimeter to 0.2 millimeter.

[0077] In an exemplary embodiment, as Figure 4As shown, the foldable display panel 200 may further include a detection component. The detection component may include at least one sensor 205. When the foldable display panel 200 is in a flattened state, the sensor 205 is configured to detect the local strain state of the flexible display module 201. The sensor 205 may be disposed on the side of the flexible display module 201 close to the display side, and the orthographic projection of the sensor 205 on the plane where the foldable display panel 200 is located is within the orthographic projection of the bending region BB on the plane where the foldable display panel 200 is located. Alternatively, the sensor 205 may be embedded within the flexible display module 201, and the surface of the sensor 205 on the side away from the electroosmotic pump structure layer 204 may be substantially flush with the surface of the flexible display module 201 on the side away from the electroosmotic pump structure layer 204. By way of example, the surface of the sensor 205 on the side away from the electroosmotic pump structure layer 204 may be flush with the surface of the flexible display module 201 on the side away from the electroosmotic pump structure layer 204, or the distance between the surface of the sensor 205 on the side away from the electroosmotic pump structure layer 204 and the surface of the flexible display module 201 on the side away from the electroosmotic pump structure layer 204 is within a set range. In the embodiments of the present disclosure, arranging the sensor 205 as close as possible to the display side can improve the accuracy of detection and the accuracy of flatness adjustment.

[0078] In an exemplary embodiment, as Figure 4 shown, the foldable display panel 200 may further include a control chip 206. The control chip 206 may be embedded within the flexible display module 201, or the control chip 206 may be located between the adhesive layer 202 and the support layer 203, or the control chip 206 may be disposed between the base material 204-5 and the second electrode layer 204-2. The present disclosure does not limit the specific arrangement position of the control chip 206, and the control chip 206 may be integrated with other chips of the foldable display panel 200. The orthographic projection of the control chip 206 on the plane where the foldable display panel 200 is located does not overlap with the orthographic projection of the bending region BB on the plane where the foldable display panel 200 is located, avoiding the influence of bending on the performance of the control chip 206, reducing the design requirements for the control chip 206, and reducing the manufacturing cost of the control chip 206.

[0079] The detection component and the electroosmotic pump structure layer 204 are both electrically connected to the control chip 206, and the detection component transmits the detected strain to the control chip 206. Then, the control chip 206 can compare the received strain with the corresponding reference strain to control the operation of the electroosmotic pump structure layer 204, and adjust the flatness of the flexible display module 201 by controlling the amount of deformation and the position of deformation of the flexible layer 204-3. The reference strain is data pre-stored in the control chip 206. By way of example, the reference strain may be the strain of the corresponding area between the flexible display module 201 and the detection component when the bending area BB is in a flattened state and the flatness of the flexible display module 201 meets the design state.

[0080] By way of example, the detection component may include two sensors 205. The reference strains of the flexible display module 201 corresponding to the two sensors 205 may be the same or different. The two sensors 205 transmit the detected strain to the control chip 206, and then the control chip 206 compares the two received strains with the corresponding reference strains to control the operation of the electroosmotic pump structure layer 204. By way of example, by controlling the different amounts of deformation of the flexible layer 204-3 in the areas corresponding to the two sensors 205, the zonal adjustment of the flexible display module 201 corresponding to the two sensors 205 can be achieved.

[0081] In an exemplary embodiment, the sensor 205 may be an ultra-thin resistive strain sensor, a capacitive flexible sensor, a flexible stretchable strain sensor, or the like.

[0082] Figure 6A FIG. is a schematic structural diagram of a foldable display panel according to an embodiment of the present disclosure in a folded state. Figure 6B FIG. is a schematic structural diagram of a foldable display panel according to an embodiment of the present disclosure in a flattened state. Figure 7A FIG. is a schematic structural diagram of a foldable display panel according to another embodiment of the present disclosure in a folded state. Figure 7B FIG. is a schematic structural diagram of a foldable display panel according to another embodiment of the present disclosure in a flattened state. As Figure 6A 、 Figure 6B 、 Figure 7A and Figure 7B shown, the foldable display panel is in different folded states, resulting in different flattened states of the foldable display panel, and different deformations of the flexible layer 204-3 of the electroosmotic pump structure layer 204 located in the bending area BB, as shown by the dashed boxes in Figure 6B and Figure 7B . The electroosmotic pump structure layer 204 can adjust the flexible display module 201 with different flatnesses located in the bending area BB to make the flatness of the flexible display module 201 located in the bending area BB meet the design requirements. As Figure 6B andFigure 7B As shown, all are flexible display modules 201 after the electroosmotic pump structure layer 204 is adjusted.

[0083] Figure 8A It is a schematic diagram of the deformation of the flexible layer of the electroosmotic pump structure layer according to an embodiment of the present disclosure. Figure 8B It is a schematic diagram of the deformation of the flexible layer of the electroosmotic pump structure layer according to another embodiment of the present disclosure. Figure 8C It is a schematic diagram of the deformation of the flexible layer of the electroosmotic pump structure layer according to still another embodiment of the present disclosure. As Figure 8A 、 Figure 8B and Figure 8C shown, the shape of the flexible layer 204-3 after deformation can be any shape. By way of example, in a plane perpendicular to the plane of the foldable display panel, the shape of the surface of the flexible layer 204-3 on the side away from the substrate 204-5 can be arc-shaped or wavy or include a plurality of spaced-apart arcs, etc. However, the present disclosure does not limit this.

[0084] The embodiments of the present disclosure provide a display device, and the display device may include the foldable display panel of any of the foregoing embodiments. The display device of the present disclosure may be a foldable display device, and the display device may be: a mobile phone, a tablet computer, a television, a monitor, a laptop computer, a digital photo frame, a navigator, or any other product or component with a display function. The present disclosure does not limit this here.

[0085] Although the disclosed embodiments are as above, the content described is only an embodiment adopted for the convenience of understanding the present invention and is not used to limit the present invention. It should be noted that the above embodiments or embodiments are merely exemplary and not restrictive. Therefore, the present disclosure is not limited to the content specifically shown and described herein. Various modifications, substitutions or omissions can be made to the form and details of the implementation without departing from the scope of the present disclosure.

Claims

1. A foldable display panel, characterized in that, It includes at least one bending area and multiple non-bending areas, and one of the bending areas is located between two adjacent non-bending areas; the bending area is configured to be switchable between a folded state and a flattened state; The foldable display panel includes a flexible display module and an electroosmotic pump structure layer arranged in a stacked manner, and parts of the flexible display module and the electroosmotic pump structure layer are both located in the bending area; the electroosmotic pump structure layer is configured to adjust the flatness of the flexible display module located in the bending area when the bending area is in the flattened state.

2. The foldable display panel according to claim 1, wherein The electroosmotic pump structure layer includes a substrate, a second electrode layer, a porous dielectric film, a first electrode layer, and a flexible layer arranged in a stacked manner in sequence; the flexible layer is closer to the flexible display module than the substrate, and at least part of the flexible layer is located in the bending area; The porous dielectric film has a plurality of microchannels, the microchannels are filled with an electrolyte, and the porous dielectric film and the electrolyte form an electric double layer; The first electrode layer and the second electrode layer are configured to form an electric field to drive the movement of ions in the electric double layer, so that the flexible layer deforms.

3. The foldable display panel according to claim 2, wherein The foldable display panel further includes a detection component and a control chip, and the detection component and the electroosmotic pump structure layer are both electrically connected to the control chip, and the detection component is located in the bending area; the detection component includes at least one sensor, and the sensor is configured to detect the strain of the flexible display module located in the bending area and in the flattened state, and transmit the detected strain to the control chip; The control chip is configured to control the amount of deformation of the flexible layer according to the received strain.

4. The foldable display panel according to claim 3, wherein The control chip is configured to control the electric field formed by the second electrode layer and the first electrode layer according to the received strain, so as to control the amount of deformation of the flexible layer.

5. The foldable display panel according to claim 4, wherein At least one of the second electrode layer and the first electrode layer includes a plurality of electrodes arranged at intervals.

6. The foldable display panel according to claim 3, wherein The range of the amount of deformation is from 0.1 mm to 0.2 mm.

7. The foldable display panel according to claim 3, wherein The detection component is located on the side of the flexible display module away from the electroosmotic pump structure layer; or at least part of the detection component is embedded in the flexible display module.

8. The foldable display panel according to claim 2, wherein In a plane perpendicular to the plane where the foldable display panel is located, in the structure where the flexible layer deforms, the shape of the surface of the flexible layer away from the substrate side includes at least one of an arc shape or a wavy shape.

9. The foldable display panel according to any one of claims 1 to 8, characterized in that, The thickness range of the electroosmotic pump structure layer is from 0.25 mm to 0.5 mm.

10. A display device, characterized in that, It includes the foldable display panel according to any one of claims 1 to 9.

Images