Flexible display screen and preparation method and testing device and testing method thereof

Abstract

The application provides a flexible display screen, a preparation method and test equipment and a test method thereof, and solves the problem that the impact resistance of the flexible display screen cannot be quantified in the prior art. The flexible display screen comprises a substrate, a functional film layer on one side of the substrate, and a force sensor corresponding to the functional film layer. The sensing signal generated by the force sensor is used to represent the tolerance performance of the corresponding functional film layer. By means of the force sensor, the sensing signal is generated when the display screen is impacted by the test force, and the test equipment detects the sensing signal, so as to quantify the deformation of the functional film layer caused by the impact. Compared with the conventional artificial subjective judgment method, the tolerance performance of the screen body can be represented in situ.

Description

Technical Field

[0001] This application relates to the field of display technology, specifically to a flexible display screen and its preparation method, testing equipment, and testing method. Background Technology

[0002] As the bending resistance of flexible displays improves, the module materials (e.g., cover plates and polarizers) of flexible displays use thinner flexible films, resulting in reduced impact resistance and increased susceptibility to film breakage, leading to display defects. Current technology typically tests the impact resistance of flexible displays by observing the appearance of colored and black dots on the screen when it is lit, after the screen has been subjected to an impact of a certain weight. This method relies heavily on the subjective judgment of the operator, leading to significant errors in the resulting impact resistance assessments and failing to quantify the screen's impact resistance. Summary of the Invention

[0003] In view of this, the embodiments of this application aim to provide a flexible display screen and its manufacturing method, testing equipment, and testing method to solve the problem that the impact resistance of flexible display screens cannot be quantified in the prior art.

[0004] The first aspect of this application provides a flexible display screen, which includes: a substrate, a functional film layer located on one side of the substrate, and a force sensor corresponding to the functional film layer; the sensing signal generated by the force sensor is used to characterize the tolerance performance of the corresponding functional film layer.

[0005] In some embodiments, a force sensor is used to sense a test force applied to the flexible display screen to generate a sensing signal.

[0006] In some embodiments, the functional membrane layer and its corresponding force sensor are disposed in the same layer and are made of the same material.

[0007] In some embodiments, there is one functional film layer, or multiple functional film layers are stacked along the thickness direction of the substrate, and different functional film layers correspond to different force sensors.

[0008] In some embodiments, the flexible display screen further includes a driving array layer, which includes an active layer, a gate insulating layer, a gate layer, an interlayer insulating layer, and a source / drain layer stacked on one side of the substrate and along the thickness direction of the substrate. The functional film layer includes one or at least two of the active layer, the gate layer, and the source / drain layer.

[0009] In some embodiments, the functional film layer includes a source / drain layer, which includes a metal layer.

[0010] In some embodiments, the source-drain layer includes a first metal layer, a second metal layer, and a third metal layer sequentially stacked along the thickness direction of the substrate, wherein the first metal layer and the third metal layer are made of titanium, and the second metal layer is made of aluminum.

[0011] In some embodiments, the force sensors corresponding to the same functional film layer are multiple and at least distributed in the display area of ​​the flexible display screen.

[0012] In some embodiments, the flexible display screen includes at least two non-bending regions and at least one bending region, with the bending region located between two adjacent non-bending regions; among the force sensors corresponding to the same functional film layer, each bending region is provided with at least one force sensor, and each non-bending region is provided with at least two force sensors.

[0013] In some embodiments, force sensors corresponding to the same functional membrane layer are evenly arranged on both sides with the bending axis of the bending region as the center line.

[0014] In some embodiments, the force sensor is connected to the detection point of the flexible display via a connecting lead.

[0015] In some embodiments, the force sensor includes a resistive sensor and / or a capacitive sensor.

[0016] In some embodiments, the shape of the force sensor includes one or more of the following: herringbone, square wave, wavy, straight, and rectangular.

[0017] A second aspect of this application provides a method for fabricating a flexible display screen, comprising: forming an original film layer on a substrate; patterning the original film layer to obtain a functional film layer and a force sensor, wherein the sensing signal generated by the force sensor is used to characterize the tolerance performance of the corresponding functional film layer.

[0018] A third aspect of this application provides a testing device for testing a flexible display screen provided in any embodiment of this application. The testing device includes: a force-applying element for applying a test force to the flexible display screen; and a signal processing unit for receiving a sensing signal generated by a force sensor.

[0019] In some embodiments, the force-applying element includes a ball and / or a steel needle.

[0020] In some embodiments, the testing equipment further includes a support unit for supporting a flattened flexible display screen.

[0021] A fourth aspect of this application provides a testing method for testing flexible displays provided in any embodiment of this application. The testing method includes: applying the same test force to multiple flexible displays using a force-applying element; determining the tolerance performance of the same functional film layer of the multiple flexible displays based on the sensing signal generated by the force sensor received by the signal processing unit, wherein the smaller the absolute value of the change in the sensing signal, the higher the tolerance performance of the functional film layer of the flexible display; and / or applying a test force to the same flexible display using a force-applying element; determining the tolerance performance of different functional film layers of the same flexible display based on the sensing signal generated by the force sensor received by the signal processing unit.

[0022] According to the flexible display screen provided in this application, the sensing signal generated by the force sensor corresponding to the functional film layer can be used to characterize the tolerance performance of the corresponding functional film layer, which facilitates the detection of the sensing signal by the testing equipment, thereby quantifying the deformation of the flexible display screen caused by the test force. Compared with the conventional human subjective judgment method, designing a force sensor inside the flexible display module can achieve the effect of in-situ testing, thereby characterizing the tolerance performance of the screen. Attached Figure Description

[0023] Figure 1 This is a cross-sectional schematic diagram of a flexible display screen provided in an embodiment of this application.

[0024] Figure 2 This is a cross-sectional schematic diagram of a flexible display panel provided in an embodiment of this application.

[0025] Figure 3 This is a schematic diagram of the structure of a flexible display screen provided in an embodiment of this application.

[0026] Figure 4 This is a schematic diagram of the structure of a flexible display screen provided in another embodiment of this application.

[0027] Figure 5 This is a schematic diagram of the structure of a test device provided in one embodiment of this application.

[0028] Figure 6 This is a flowchart illustrating a testing method provided in one embodiment of this application.

[0029] Figure 7 This is a flowchart illustrating a testing method provided in another embodiment of this application.

[0030] Figure 8 This is a schematic diagram of a test waveform provided in an embodiment of this application.

[0031] Figure 9 This is a schematic diagram of a method for fabricating a flexible display screen according to an embodiment of this application. Detailed Implementation

[0032] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0033] As described in the background section, to achieve flexible folding, the module materials on the screen, such as the cover plate and polarizer, use thin flexible films. Compared to hard screen glass covers, the impact resistance of foldable phone screens is reduced. Because the film layers of the display module are thin and inorganic film layers are brittle, the screen is prone to film layer breakage and display defects when subjected to external impact. Existing technologies primarily test the impact resistance of flexible displays by observing colored or black dots appearing on the screen when it is lit, characterizing the failure of the flexible display after being subjected to impact. However, this characterization method involves a degree of subjective judgment and cannot quantify the screen's impact resistance. Therefore, this application provides a flexible display that introduces a force sensor that can characterize strain in situ within the functional film layers of the display. This force sensor allows the display to output the actual strain value experienced by the display when subjected to external impact. Compared to conventional subjective judgment methods, this method can quantify the screen's impact resistance in situ.

[0034] The flexible display screen will be described in detail below with reference to specific embodiments.

[0035] Figure 1 This is a cross-sectional schematic diagram of a flexible display screen provided in an embodiment of this application. Figure 1As shown, the flexible display screen 10 may include a flexible display panel 20, and one or more of the following stacked on top of the flexible display panel 20: a support sheet 101, a support layer 102, a support film 103, a first pressure-sensitive adhesive layer 104, a second pressure-sensitive adhesive layer 105, a polarizer 106, an optical adhesive layer 107, and a cover plate 108. The support sheet 101 is a metal support or heat sink, and can be a stainless steel sheet or other bendable metal sheet, or a patterned perforated metal sheet to achieve bending. The support layer 102 is double-sided foam adhesive, and the substrate can be foam, polyethylene terephthalate (PET), or polyimide (PI), etc., coated with adhesive on both sides to achieve adhesion to the screen side, preventing metal impact and providing stress protection. The support film 103 can be made of PI or PET, etc. The first pressure-sensitive adhesive layer 104 is a supporting film adhesive material, and the first pressure-sensitive adhesive layer 104 can be made of materials such as acrylate. The polarizer 106 can be a combination of polypropylene alcohol and a phase retardation film.

[0036] The flexible display screen 10 may include a flexible display panel 20. The flexible display panel 20 may include a substrate 201, a functional film layer 200 located on one side of the substrate 201, and a force sensor 300 corresponding to the functional film layer 200.

[0037] Optionally, the sensing signal generated by the force sensor 300 is used to characterize the tolerance performance of the corresponding functional film layer 200. The changes in the force sensor 300 and the corresponding functional film layer 200 under the test force applied to the flexible display screen 10 are the same or similar.

[0038] There may be multiple force sensors 300, and they extend along the lateral direction of the display surface of the flexible display screen 10 (i.e., Figure 1 The L-direction shown is arranged in an array. For example, the display surface of the flexible display screen 10 refers to the side of the flexible display screen 10 that can display images, which is opposite to the non-display surface of the flexible display screen 10.

[0039] For example, the flexible display screen 10 may include an organic light-emitting diode (OLED) display screen, etc. Of course, the OLED display screen may also be a double-sided display, depending on the actual situation. The flexible display screen 10 is foldable.

[0040] The flexible display panel 20 may include a substrate and a driving array layer located on one side of the substrate. The driving array layer may include semiconductor layers, conductive layers, and insulating layers stacked along the thickness direction of the substrate to form structures such as thin-film transistors, storage capacitors, scan lines, data lines, and light-emitting control lines. The functional film layer 200 may be located in the driving array layer. The functional film layer 200 may include the semiconductor layer and / or conductive layer in the driving array layer. The functional film layer 200 may be a conductive layer, such as a metal layer, or a semiconductor layer, such as a polycrystalline silicon film layer; this application does not impose specific limitations on this.

[0041] Optionally, the force sensor 300 is used to sense the test force applied to the flexible display screen 10 to generate a sensing signal. The sensing signal generated by the force sensor 300 can be transmitted to the test equipment.

[0042] For example, when the flexible display screen 10 is subjected to a test force, the force sensor 300 and the corresponding functional film layer 200 deform, and their resistance or capacitance values ​​change linearly.

[0043] For example, under the action of test forces such as impact, the resistance or capacitance value of the force sensor 300 changes, resulting in a change in the sensing signal. The impact resistance performance of the flexible display screen can be characterized by the sensing signal.

[0044] For example, the force sensor 300 includes a resistive sensor and / or a capacitive sensor. The material of the force sensor 300 may be a metal or a semiconductor.

[0045] Optionally, the shape of the force sensor 300 includes one or more of the following: herringbone, square wave, wavy, straight, and rectangular. This application does not specifically limit the type and shape of the force sensor 300, as long as the force sensor 300 can sense the test force applied to the flexible display screen 10.

[0046] Specifically, multiple force sensors 300 can correspond one-to-one with multiple signal acquisition lines. The output terminals of the force sensors 300 are electrically connected to the signal acquisition lines, and the sensed signals are collected through the signal acquisition lines. The multiple force sensors 300 can be arranged in an M×N array. This application is only for illustrative purposes and does not limit the number of force sensors 300 along the row and column directions.

[0047] In some embodiments, the force sensor 300 is a resistive sensor. Resistive sensors exhibit a strain effect, meaning they undergo mechanical deformation under external force, causing a corresponding change in resistance. Specifically, the induced signal generated by the force sensor 300 changes with its resistance value. When the flexible display screen 10 is subjected to an external impact, the resistive sensor undergoes mechanical deformation. The testing equipment can detect the change in the induced signal in the force sensor 300, thus determining the change in its resistance value. By analyzing this change in resistance, the deformation of the functional film layer 200 caused by the impact can be quantified, thereby characterizing the impact resistance of the functional film layer 200 in situ.

[0048] above Figure 1 The module structure shown has multiple force sensors installed on the same layer as the functional film layer of the flexible display screen. By using the sensing signals generated by the force sensors when the display screen is subjected to a test force impact, the deformation of the functional film layer caused by the impact can be quantified. Designing force sensors inside the flexible display screen can achieve the effect of in-situ testing, so as to directly reflect, evaluate or judge the resistance performance (such as brittleness and toughness) of the functional film layer corresponding to the force sensor.

[0049] In some embodiments, the sensing signal generated by the force sensor 300 is used to characterize the resistance performance of the corresponding functional film layer 200. Optionally, the functional film layer 200 and its corresponding force sensor 300 are disposed in the same layer and made of the same material. The functional film layer 200 and its corresponding force sensor 300 can be formed in the same process, obtained by patterning the same original film layer. When the flexible display is subjected to test forces such as impact, the functional film layer 200 and its corresponding force sensor 300 disposed in the same layer change in the same way under the impact force. Therefore, the force sensor 300 can characterize the deformation of the corresponding functional film layer 200 and its resistance performance to test forces in situ. The larger the absolute value of the change in the sensing signal of the force sensor 300 before and during the application of the test force, the worse the resistance performance of the functional film layer 200. The smaller the absolute value of the change in the sensing signal of the force sensor 300 before and during the application of the test force, the better the resistance performance of the functional film layer 200.

[0050] Optionally, there may be one functional film layer 300. Optionally, there may be multiple functional film layers 200 stacked together along the thickness direction Z of the substrate 201. Different functional film layers 200 correspond to different force sensors 300.

[0051] Figure 2 This is a cross-sectional schematic diagram of a flexible display panel provided in one embodiment of this application. Optionally, see [link to relevant documentation]. Figure 2The driving array layer includes an active layer 203, a gate insulating layer 204, a gate layer, an interlayer insulating layer 205, and a source / drain layer, which are stacked on one side of the substrate 201 and along the thickness direction Z of the substrate 201. The functional film layer 200 includes one or at least two of the active layer 203, the gate layer, and the source / drain layer.

[0052] In this design, the gate layer and the source / drain layer are conductive layers, such as metal layers. The gate layer can be metal layer M1. The source / drain layer can be metal layer M3.

[0053] Optional, see Figure 2 The functional film layer 200-1 is the source / drain layer. The force sensor 300-1, corresponding to the source / drain layer, is disposed in the same layer as the source / drain layer and is made of the same material. The sensing signal generated by the force sensor 300-1 is used to characterize the deformation and tolerance performance of the source / drain layer. The force sensor 300-1 is used to sense the test force applied to the flexible display screen to generate a sensing signal, so as to determine the deformation and tolerance performance of the source / drain layer based on the sensing signal generated by the force sensor 300-1.

[0054] Optionally, the functional film layer 200-2 is an active layer 203. The force sensor 300-2 corresponding to the active layer 203 is disposed in the same layer as the active layer 203 and is made of the same material. The force sensor 300-2 corresponding to the active layer 203 is used to characterize the deformation and resilience of the active layer 203. The force sensor 300-2 is used to sense the test force applied to the flexible display screen to generate a sensing signal, so as to determine the deformation and resilience of the active layer 203 based on the sensing signal generated by the force sensor 300-2.

[0055] For example, the strength and durability of the source and drain layers of multiple flexible displays can be compared and judged based on the sensing signals generated by the force sensors 300-1 corresponding to the source and drain layers of the displays.

[0056] For example, the quality of the endurance performance of the active layers 203 of multiple flexible displays can be compared and judged based on the sensing signals generated by the force sensors 300-2 corresponding to the active layers 203 of the multiple flexible displays.

[0057] By continuously increasing the test force until the sensing signal generated by the force sensor 300 reaches its limit value, at which point the resistance of the force sensor 300 becomes infinite, it indicates that the force sensor 300 has broken. Thus, the maximum test force that the functional membrane layer can withstand can be obtained.

[0058] Optionally, when there are multiple functional film layers 200 stacked along the thickness direction Z of the substrate 201, the force sensors 300 corresponding to different functional film layers 200 can be directly opposite or staggered along the thickness direction Z of the substrate 201.

[0059] The durability of different functional layers of the same flexible display screen can be compared and judged based on the sensing signals generated by force sensors corresponding to different functional layers. For example, when there are multiple functional layers 200, where functional layer 200-1 is the source / drain layer and functional layer 200-2 is the active layer, the durability of the source / drain layer and the active layer of the same flexible display screen can be determined based on the sensing signals generated by force sensors 300-1 and 300-2.

[0060] like Figure 2 As shown, optionally, the driving array layer includes a water and oxygen barrier layer 202, an active layer 203, a gate insulating layer 204, a first conductive layer M1, a first interlayer insulating layer 205, a second conductive layer M2, a second interlayer insulating layer 206, a third conductive layer M3, a passivation layer 207, a first planarization layer 208, a fourth conductive layer M4, a second planarization layer 209, an anode layer 219, a pixel defining layer 210, a light-emitting layer 215, a cathode layer 216, an encapsulation layer 217, and a touch layer 218.

[0061] The substrate 201 can be a flexible substrate, such as a resin substrate, paper substrate, or biocomposite film substrate. The material of the substrate 20 can include polyimide, etc. The water and oxygen barrier layer 202 can be an inorganic layer. The material of the water and oxygen barrier layer 202 can be any one or a combination of two or more of silicon oxide, silicon nitride (refractive index 2.05), aluminum oxide (refractive index 1.77), titanium oxide (refractive index 2.65), and zirconium oxide (refractive index 2.17). Optionally, the water and oxygen barrier layer 202 can be made of aluminum oxide, which has a lower refractive index. The gate insulating layer 204 can be an inorganic layer; for example, the material of the gate insulating layer 204 can include one or more of silicon nitride (SiNx) and silicon oxide (SiOx). The first interlayer insulating layer 205 and the second interlayer insulating layer 206 can be inorganic layers; for example, the materials of the first interlayer insulating layer 205 and the second interlayer insulating layer 206 can include one or more of silicon nitride (SiNx) and silicon oxide (SiOx). The first planarization layer 208 and the second planarization layer 209 can be organic layers, for example, the materials of the first planarization layer 208 and the second planarization layer 209 can be polyimide. The pixel defining layer 210 can be an organic layer, and the material of the pixel defining layer 210 can include at least one of polyimide, acrylate-based, and epoxy resin-based materials. The pixel defining layer 210 has multiple openings, and a light-emitting layer 215 is disposed within each opening. The encapsulation layer 217 completely covers the pixel defining layer 210 and the light-emitting layer 215. The first conductive layer M1, the second conductive layer M2, the third conductive layer M3, and the fourth conductive layer M4 can be metal layers.

[0062] In some embodiments, the functional film layer 200 includes a source / drain layer. The source / drain layer may include a metal layer. Optionally, the source / drain layer includes a first metal layer, a second metal layer, and a third metal layer sequentially stacked along the thickness direction Z of the substrate 201. The first and third metal layers are made of titanium, and the second metal layer is made of aluminum. Considering that titanium-aluminum-titanium metal materials have excellent ductility and stretchability, the change in resistance of the source / drain layer can be tested by impact resistance testing, thereby quantifying the deformation of the metal caused by impact, etc. Without affecting the display function of the transistor, the purpose of in-situ characterizing the impact resistance of the screen is achieved.

[0063] For example, the active layer 203 may include a source region 231, a drain region 232, and a channel region 233 located between the source region 231 and the drain region 232. The source-drain layer may be connected to the source region 231 and the drain region 232 via vias.

[0064] For example, a gate insulating layer 204 may be disposed between the first conductive layer M1 and the active layer 203. A first interlayer insulating layer 205 may be disposed between the second conductive layer M2 and the first conductive layer M1. A second interlayer insulating layer 206 may be disposed between the third conductive layer M3 and the second conductive layer M2. A passivation layer 207 and a first planarization layer 208 may be disposed between the fourth conductive layer M4 and the third conductive layer M3.

[0065] For example, the materials of the first conductive layer M1, the second conductive layer M2, the third conductive layer M3 and the fourth conductive layer M4 include, but are not limited to, one or more of the following metallic materials: aluminum, molybdenum, copper, silver, chromium, titanium, titanium-aluminum-titanium, molybdenum-titanium.

[0066] In some embodiments, the gate of the transistor may be formed in the first conductive layer M1, and the source and drain of the transistor may be formed in the third conductive layer M3.

[0067] In some embodiments, the functional film layer 200 can be any one of the active layer 203, the first conductive layer M1, the second conductive layer M2, the third conductive layer M3, and the fourth conductive layer M4. In addition, signal lines such as scan lines, data lines, and power lines can also be disposed within the first conductive layer M1, the second conductive layer M2, the third conductive layer M3, and the fourth conductive layer M4. By detecting changes in the film layer where the force sensor 300 is located using an impact resistance testing device, the impact resistance capability of the screen can be quantitatively characterized in situ.

[0068] In some embodiments, a third conductive layer M3 can be formed above the substrate 201, and a photoresist layer can be formed on the third conductive layer M3. The photoresist layer is exposed and developed. Then, the third conductive layer M3 is patterned to obtain the source and drain patterns of the transistors in the gate drive circuit. A herringbone-shaped force sensor 300-1 can also be obtained. Of course, other shapes of force sensors 300-1, such as square waveforms, wavy shapes, straight lines, and rectangles, can also be obtained through processing. It should be understood that the fabrication method of the force sensor in this embodiment is also applicable to the active layer, the first conductive layer M1, the second conductive layer M2, and the fourth conductive layer M4.

[0069] In some embodiments, multiple force sensors are obtained by patterning the membrane layer containing the functional membrane layer.

[0070] Figure 3 This is a schematic diagram of the structure of a flexible display screen provided in one embodiment of this application. Figure 3 As shown, there are multiple force sensors 300 corresponding to the same functional membrane layer, and they are at least distributed in the display area of ​​the flexible display screen 10.

[0071] Optionally, the flexible display screen 10 includes at least two non-bending areas and at least one bending area, with the bending area located between two adjacent non-bending areas.

[0072] Optionally, among the force sensors corresponding to the same functional membrane layer, at least one force sensor is provided in any bending region, and at least two force sensors are provided in any non-bending region.

[0073] like Figure 3 As shown, the flexible display screen 10 includes a bending area 211 and two non-bending areas located on opposite sides of the bending area 211, namely the first non-bending area 221 and the second non-bending area 222. A force sensor 300 is provided in the bending area 211, and two force sensors 300 are provided in both the first non-bending area 221 and the second non-bending area 222.

[0074] Specifically, due to its inherent folding properties, the material of the bending area 211 possesses a certain degree of flexibility, leading to a decrease in its impact resistance. Therefore, at least one force sensor 300 needs to be installed in the bending area 211 to test its impact resistance. Simultaneously, to characterize the differences in impact resistance at different locations of the flexible display screen 10, at least two force sensors 300 are installed in the first non-bending area 221 and the second non-bending area 222 to test the impact resistance of the non-bending area 220.

[0075] It should be understood that the number of force sensors 300 deployed is not limited to... Figure 3The five force sensors shown can also be other values. The number of force sensors 300 should be sufficient to avoid occupying too much space in the thin-film transistors and affecting the display of the device. As long as the force sensors 300 can characterize the impact resistance of the entire display surface, it is acceptable. The specific number can be set according to the actual situation.

[0076] In some embodiments, continue to refer to Figure 3 Force sensors 300 corresponding to the same functional film layer are evenly arranged on both sides with the bending axis of the bending region 211 as the center line. The number of force sensors 300 in the first non-bending region 221 and the second non-bending region 22 is the same, and the force sensors 300 are evenly distributed, which is more conducive to characterizing the test force on the display surface of the flexible display screen 10.

[0077] Specifically, multiple force sensors 300 are evenly distributed on the display surface of the flexible display screen 10, which can test the difference in impact resistance at different locations of the flexible display screen 10. That is, when a test force is applied to the bending area 211 or the non-bending area of ​​the flexible display screen 10, the actual strain value of the flexible display screen 10 can be output, thus characterizing the impact resistance of the screen in situ.

[0078] In one embodiment, continue to refer to Figure 3 The force sensors 300 in the bending area 211 and the two non-bending areas on opposite sides of the bending area 211 are both in a meander shape (or spiral shape). Compared with the long or square force sensors 300 with a pointed tip, the meander-shaped force sensors 300 make it easier to distribute the impact pressure evenly and better represent the actual strain of the entire screen.

[0079] Figure 4 This is a schematic diagram of the structure of a flexible display screen provided in another embodiment of this application. Figure 4 As shown, the flexible display screen 10 includes a first bending area 212, a second bending area 213, a third non-bending area 223, a fourth non-bending area 224, and a fifth non-bending area 225. The third non-bending area 223 and the fourth non-bending area 224 are located on both sides of the first bending area 212, and the fourth non-bending area 224 and the fifth non-bending area 225 are located on both sides of the second bending area 213. Each of the first bending area 212 and the second bending area 213 is provided with a herringbone-shaped force sensor 300. Each of the third non-bending area 223, the fourth non-bending area 224, and the fifth non-bending area 225 is provided with two herringbone-shaped force sensors 201.

[0080] Optionally, the first bending area 212 can be folded inward or outward. Optionally, the second bending area 213 can be folded inward or outward. It should be understood that the first bending area 212 can be folded inward, and the second bending area 213 can be folded outward. Optionally, the first bending area 212 can be folded outward, and the second bending area 213 can be folded inward.

[0081] When the bend is inward, the display surfaces of adjacent non-bend areas on both sides of the bend face each other, while the non-display surfaces face away from each other. When the bend is outward, the non-display surfaces of adjacent non-bend areas on both sides of the bend face each other, while the display surfaces face away from each other.

[0082] The flexible display screen provided in this application, by setting multiple force sensors 300 evenly distributed on the display surface of the flexible display screen 10, can test the difference in impact resistance at different locations of the flexible display screen 10, thereby characterizing the impact resistance of the screen in situ.

[0083] In some embodiments, the force sensor 300 is connected to the detection point of the flexible display screen 10 via a connecting lead, so that the sensing signal generated by the force sensor 300 is transmitted to the testing equipment through the detection point. The detection point may include pads, etc.

[0084] Specifically, the detection point is used to collect the sensing signals generated by multiple force sensors 300. The multiple force sensors 300 are connected to the detection point of the flexible display screen 10 via connecting leads, which is equivalent to guiding the strain value signals detected by all force sensors 300 to the detection point so that the testing equipment can perform impact resistance testing.

[0085] Optionally, the flexible display also includes a flexible circuit board that can be bonded to the detection site. The flexible circuit board can be electrically connected to the signal processing unit of the test equipment to transmit the sensed signal generated by the force sensor 300 to the test equipment.

[0086] Figure 5 This is a schematic diagram of the structure of a test device provided in one embodiment of this application. Figure 5 As shown, the testing equipment can be used to test the flexible display screen 10 provided in any of the above embodiments. The testing equipment includes: a force-applying element 500 and a signal processing unit 501.

[0087] The force-applying element 500 is used to apply a test force to the flexible display screen 10; the signal processing unit 501 is used to receive the sensing signal generated by the force sensor 300.

[0088] In one embodiment, after the signal processing unit 501 receives the sensing signal generated by the force sensor 300, it analyzes and judges the sensing signal to determine the durability of the flexible display screen 10. The smaller the change in the sensing signal, the higher the durability of the functional film layer 200 of the flexible display screen. When the sensing signal line is broken, the resistance will be infinitely large, indicating that the flexible display screen cannot withstand the excessive test force applied to it by the force-applying element, thus indicating poor durability of the flexible display screen.

[0089] Optionally, the force-applying element 500 includes: a ball and / or a steel needle.

[0090] Optional, such as Figure 5 As shown, the testing equipment also includes a support unit 502 for supporting the flattened flexible display screen 10.

[0091] Figure 6 This is a schematic flowchart illustrating a testing method provided in one embodiment of this application. The testing method can be used to test the flexible display screen provided in any of the above embodiments. Figure 6 As shown, the testing method for this flexible display screen includes the following steps.

[0092] In step S600, the same test force is applied to multiple flexible displays using a force-applying element.

[0093] Step S601: Determine the tolerance performance of the same functional film layer of multiple flexible displays based on the sensing signal generated by the force sensor received by the signal processing unit.

[0094] Among them, the smaller the absolute value of the change in the sensed signal, the higher the tolerance performance of the functional film layer of the flexible display screen 10.

[0095] The testing method provided in this application embodiment can receive the sensing signal generated by the force sensor through the signal processing unit, and determine the resistance performance of the same functional film layer 200 of multiple flexible displays 10 based on the sensing signal of the force sensor 300 corresponding to the same functional film layer 200, so as to achieve the purpose of characterizing the impact resistance of the screen in situ.

[0096] Figure 7 This is a flowchart illustrating a testing method provided in another embodiment of this application. The testing method is used to test the flexible display screen described in any of the above embodiments. Figure 7 As shown, the testing method for this flexible display screen includes the following steps.

[0097] In step S800, a test force is applied to the same flexible display screen using a force-applying element.

[0098] Step S801: Determine the tolerance performance of different functional film layers of the same flexible display screen based on the sensing signal generated by the force sensor received by the signal processing unit.

[0099] In practical applications, different functional film layers of a flexible display screen correspond to different force sensors. When conducting impact resistance testing, the force sensor senses the impact force applied to the flexible display screen and generates a sensing signal. The testing equipment detects the sensing signal and transmits it to the signal processing unit of the testing equipment for analysis, thereby determining the resistance performance of different functional film layers of the same flexible display screen.

[0100] Optionally, the testing method for flexible displays may include steps S600, S601, S800, and S801.

[0101] In this method, by increasing the test force applied to the same flexible display screen by the force-applying element until the sensing signal generated by the force sensor reaches the limit value, the resistance of the force sensor 300 becomes infinite, indicating that the force sensor 300 has broken. Thus, the maximum test force that the functional film layer can withstand can be obtained.

[0102] Figure 8 This is a schematic diagram of a test waveform provided in an embodiment of this application. The horizontal axis represents time T, and the vertical axis represents the resistance value R of the force sensor, as shown below. Figure 8 As shown, before the impact resistance test of the flexible display screen, the resistance of the force sensor is r1 at time 0s. At time t, the instant of impact, the resistance of the force sensor changes to r2. By analyzing the change in resistance during the impact resistance test, the impact resistance of the flexible display screen can be determined.

[0103] Figure 9 This is a schematic diagram illustrating a method for fabricating a flexible display screen according to an embodiment of this application. This method can be used to manufacture the flexible display screen provided in the above embodiment. Figure 9 As shown, the preparation method includes the following steps.

[0104] Step S701: Form the original film layer on the substrate.

[0105] Step S704: Pattern the original membrane layer to obtain the functional membrane layer and the force sensor.

[0106] The method for preparing a flexible display screen provided in this application can be used to manufacture the flexible display screen provided in the above-mentioned embodiments. Therefore, the method for preparing a flexible display screen provided in this application has the technical effects provided in the above-mentioned embodiments, and will not be repeated here.

[0107] Optionally, the sensing signal generated by the force sensor 300 is used to characterize the tolerance performance of the corresponding functional membrane layer 200.

[0108] For example, the active layer 203 and the force sensor 300-2 can be formed through step S704. Optionally, after step S704, the method further includes: forming a second original film layer on the side of the functional film layer and the force sensor away from the substrate 201, and patterning the second original film layer to obtain the corresponding functional film layer and force sensor, for example, forming a source-drain layer and the force sensor 300-1.

[0109] Optionally, after step S701 and before step S704, the method further includes:

[0110] Step S702: A photoresist layer is formed on top of the original film layer.

[0111] Step S703: Expose and develop the photoresist layer.

[0112] Among them, the original film layer can be etched to obtain the functional film layer and the force sensor.

[0113] This application also provides a display device. The display device includes the flexible display screen provided in the above embodiments. This display device can be any product or component with display functionality, such as a mobile phone, tablet computer, television, navigation system, or in-vehicle application.

[0114] It should be understood that the qualifiers “first,” “second,” “third,” “fourth,” “fifth,” and “sixth” used in the description of the embodiments of this application are only used to more clearly illustrate the technical solutions and are not intended to limit the scope of protection of this application.

[0115] The above description has been given for purposes of illustration and description. Furthermore, this description is not intended to limit the embodiments of this application to the forms disclosed herein. Although numerous exemplary aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, alterations, additions, and sub-combinations thereof.

Claims

1. A flexible display screen, characterized in that, include: A substrate, a functional film layer located on one side of the substrate, and a force sensor corresponding to the functional film layer; The force sensor generates an inductive signal to characterize the tolerance performance of the corresponding functional membrane layer. By continuously increasing the test force until the inductive signal generated by the force sensor reaches a limit value, at which point the resistance of the force sensor is infinite, the force sensor breaks, and the maximum test force that the functional membrane layer can withstand is obtained. The flexible display screen further includes a driving array layer, which includes an active layer, a gate insulating layer, a gate layer, an interlayer insulating layer, and a source / drain layer stacked on one side of the substrate and along the thickness direction of the substrate. The functional film layer includes one or at least two of the active layer, the gate layer, and the source / drain layer. The functional film layer includes the source / drain layer, and the source / drain layer includes a metal layer; The source and drain layers include a first metal layer, a second metal layer, and a third metal layer stacked sequentially along the thickness direction of the substrate. The first and third metal layers are made of titanium, and the second metal layer is made of aluminum. The force sensor has a herringbone shape.

2. The flexible display screen according to claim 1, characterized in that, The force sensor is used to sense the test force applied to the flexible display screen to generate a sensing signal; the functional film layer and its corresponding force sensor are disposed in the same layer and are made of the same material.

3. The flexible display screen according to claim 1, characterized in that, The functional film layer may be one, or multiple functional film layers may be stacked along the thickness direction of the substrate, and different functional film layers correspond to different force sensors.

4. The flexible display screen according to any one of claims 1 to 3, characterized in that, Multiple force sensors corresponding to the same functional film layer are distributed at least in the display area of ​​the flexible display screen.

5. The flexible display screen according to any one of claims 1 to 3, wherein the flexible display screen includes at least two non-bending areas and at least one bending area, the bending area being located between two adjacent non-bending areas; among the force sensors corresponding to the same functional film layer, each bending area is provided with at least one force sensor, and each non-bending area is provided with at least two force sensors.

6. The flexible display screen according to any one of claims 1 to 3, characterized in that, The force sensor is connected to the detection point of the flexible display screen via a connecting lead. The detection site is used to collect the sensing signals generated by the multiple force sensors; The flexible display screen also includes a flexible circuit board, which is bonded to the detection site. The flexible circuit board is electrically connected to the signal processing unit of the test equipment to transmit the sensing signal generated by the force sensor to the test equipment.

7. The flexible display screen according to any one of claims 1 to 3, characterized in that, The force sensor includes a resistive sensor and / or a capacitive sensor.

8. The flexible display screen according to any one of claims 1 to 3, characterized in that, The shape of the force sensor includes one or more of the following: square wave, wavy, straight, and rectangular.

9. The flexible display screen according to claim 1, characterized in that, The force sensor is used to achieve in-situ quantitative characterization of the screen's impact resistance. The smaller the absolute value of the change in the force sensor's sensing signal before and during the application of the test force, the better the tolerance performance of the functional membrane layer.

10. The flexible display screen according to claim 3, characterized in that, The force sensors corresponding to the different functional film layers are aligned with each other along the thickness direction of the substrate.

11. The flexible display screen according to claim 3, characterized in that, The force sensors corresponding to different functional film layers are staggered along the thickness direction of the substrate.

12. The flexible display screen according to claim 3, characterized in that, Based on the sensing signals generated by the force sensors corresponding to different functional films of the same flexible display screen, the superiority or inferiority of the resistance performance of different functional films of the same flexible display screen is compared and judged.

13. A method for manufacturing a flexible display screen, characterized in that, include: The original film layer is formed on the substrate; The original membrane layer is patterned to obtain a functional membrane layer and a force sensor. The sensing signal generated by the force sensor is used to characterize the tolerance performance of the corresponding functional membrane layer. By continuously increasing the test force until the sensing signal generated by the force sensor reaches a limit value, at which point the resistance of the force sensor is infinite, the force sensor breaks, and the maximum test force that the functional membrane layer can withstand is obtained. The shape of the force sensor includes a meander shape. The flexible display screen further includes a driving array layer, which includes an active layer, a gate insulating layer, a gate layer, an interlayer insulating layer, and a source / drain layer stacked on one side of the substrate and along the thickness direction of the substrate. The functional film layer includes one or at least two of the active layer, the gate layer, and the source / drain layer. The source and drain layers include a first metal layer, a second metal layer, and a third metal layer stacked sequentially along the thickness direction of the substrate. The first and third metal layers are made of titanium, and the second metal layer is made of aluminum.

14. A testing device, characterized in that, For testing the flexible display screen as described in any one of claims 1 to 12, comprising: A force-applying element is used to apply a test force to the flexible display screen; A signal processing unit is used to receive the sensing signal generated by the force sensor.

15. The testing equipment according to claim 14, characterized in that, The force-applying element includes: a ball and / or a steel needle.

16. The testing equipment according to claim 14, characterized in that, It also includes a support unit for supporting the flattened flexible display screen.

17. A testing method, characterized in that, For testing the flexible display screen as described in any one of claims 1 to 12, comprising: The same test force is applied to multiple flexible displays using a force-applying element; Based on the sensing signal generated by the force sensor received by the signal processing unit, the tolerance performance of the same functional film layer of the multiple flexible displays is determined; And / or, apply a test force to the same flexible display screen via a force-applying element; Based on the sensing signal generated by the force sensor received by the signal processing unit, the tolerance performance of different functional film layers of the same flexible display screen is determined.

18. The test method according to claim 17, characterized in that, Before conducting an impact resistance test on the flexible display screen, the resistance of the force sensor is r1 at time 0s; at time t, the resistance of the force sensor changes to r2 at the moment of impact. By analyzing the change in resistance during the impact resistance test, the impact resistance of the flexible display screen is determined.

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