WO2020133277A1

WO2020133277A1 - Bending detection device and flexible display device

Info

Publication number: WO2020133277A1
Application number: PCT/CN2018/125067
Authority: WO
Inventors: 胡小冬; 陶波波; 刘占超; 鄢玖君
Original assignee: 深圳市柔宇科技有限公司
Priority date: 2018-12-28
Filing date: 2018-12-28
Publication date: 2020-07-02
Also published as: CN112912831A

Abstract

A bending detection device (FD), comprising a bending detection module (10) and a bending recognition circuit (12) for detecting the bending state of a flexible display screen body (FB). The bending detection module (10) comprises an elastic sensing element (100), a first conductive assembly (104) and a second conductive assembly (105). The first conductive assembly (104) and the second conductive assembly (105) are disposed opposite to each other and constitute a sensing capacitor (Cx). The elastic sensing element (100) is used for sensing a bending state of the flexible display screen body (FB), and driving the first conductive assembly (104) to generate relative movement relative to the second conductive assembly (105), so as to change a capacitance value of the sensing capacitor (Cx). The bending recognition circuit (12) is electrically connected to the sensing capacitor (Cx), and is used for detecting a change amount of a capacitance value of the sensing capacitor (Cx) and identifying a bending state of the flexible display screen body (FB) according to the change amount of the capacitance value.

Description

Bending detection device and flexible display device

Technical field

The invention relates to the technical field of flexible display, in particular to the technical field for bending detection of a flexible display screen.

Background technique

Currently, the sensing method for bending the flexible display screen is generally implemented by adding additional sensing components outside the electronic device, for example, using an external mechanical or optical sensor outside the electronic device. For example, when the display screen is bent to a certain degree, the button can be mechanically touched to detect the screen bending, or the feedback stroke can be used to realize the folding induction function; the optical sensor can also be used to detect the screen bending function. However, the above-mentioned implementation method of setting the sensing element outside the display screen to detect the screen bending results in a small integration of the display screen, increases the volume of the whole machine, and can only recognize whether the completeness of the screen reaches the threshold state, and cannot be accurate , Real-time detection of screen bending.

Summary of the invention

To solve the foregoing problems, embodiments of the present invention provide a compact bending detection device to accurately identify the bending state of a flexible display screen, thereby improving the integration and user experience of the flexible display device.

Further, a flexible display device including the aforementioned bending detection device is provided.

The embodiment of the invention discloses a bending detection device, which is used for detecting the bending state of a flexible display screen body. The bending detection device includes a bending detection module and a bending recognition circuit. The bending detection module includes an elastic sensing element, a first conductive component and a second conductive component, wherein the first conductive component is disposed opposite to the second conductive component and constitutes a sensing capacitor, and the elastic sensing element is in the flexible When the main body of the display screen is bent, the first conductive component is driven to move relative to the second conductive component, and the capacitance value of the sensing capacitor is generated with the first conductive component relative to the second conductive component Changes in relative movement. The bending recognition circuit is electrically connected to the sensing capacitor, and is used for detecting the change amount of the capacitance value of the sensing capacitor and identifying the bending state of the flexible display body according to the change amount of the capacitance value.

An embodiment of the present invention discloses a flexible display device, which includes a flexible display screen body and the aforementioned bend detection device, the elastic sensor is disposed along a direction in which the flexible display screen body bends, and the first conductive The component and the second conductive component are disposed at the edge of the flexible display screen.

Compared with the prior art, the bending detection device has a compact structure, and can accurately identify the bending state of the flexible display main body, thereby facilitating the flexible display device to execute subsequent other instructions according to the bending state.

BRIEF DESCRIPTION

In order to more clearly explain the technical solutions in the embodiments of the present invention, the drawings required in the embodiments will be briefly described below. Obviously, the drawings in the following description are only some embodiments of the present invention. Those of ordinary skill in the art can obtain other drawings based on these drawings without paying any creative labor.

1 is a schematic diagram of the side structure of a flexible display device;

2 is a partially disassembled schematic view of the side structure of the bending detection device shown in FIG. 1;

3 is an enlarged schematic structural view of a part of the bending detection device shown in FIG. 2;

4 is a schematic perspective view of the structure of the bending detection device shown in FIG. 1;

5 is an exploded schematic view of the bending detection device shown in FIG. 1;

6 is a schematic perspective view of the first conductive component of FIG. 2;

7 is a schematic diagram of a side structure when the flexible display device shown in FIG. 1 is bent;

8 is a schematic diagram of the side structure of the bending detection device shown in FIG. 1 when no bending occurs and when bending occurs;

9 is a block diagram of the circuit structure of the bending recognition circuit;

FIG. 10 is a graph of the coordinate relationship between the voltage signal and the frequency signal.

detailed description

The technical solutions in the embodiments of the present invention will be described clearly and completely in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the present invention.

The specific structure and working principle of the bending detection device will be described in detail below with reference to the drawings.

Please refer to FIG. 1, which is a schematic diagram of the side structure of the flexible display device FD. As shown in FIG. 1, the flexible display device FD includes a flexible display body FB and a bending detection device CD.

Wherein, the bending detection device CD is disposed at the edge position of the side of the flexible display main body FB, and is used to sense the bending state of the flexible display main body FB, and the bending state includes whether the flexible display main body FB is bent and Bending degree.

The flexible display main body FB is used to perform image display and can be bent along the first direction F1. The bending detection device CD includes a bending detection module 10 and a bending recognition circuit 12. In this embodiment, the flexible display main body FB may be an organic light-emitting diode (Organic Light-Emitting Diode, OLED) display.

The bending detection module 10 is used to perform the detection of the bending of the main body FB of the flexible display screen, and converts the detection result into a detection signal in the form of an electrical signal to the bending recognition circuit 12. The bending recognition circuit 12 passes the detection signal The recognition process accurately determines whether the flexible display main body FB is bent and the degree of bending.

Specifically, please refer to FIG. 2, which is a partial disassembly schematic diagram of the side structure of the bending detection device shown in FIG. 1. The bending detection module 10 includes an elastic sensing element 100, a first conductive component 104 and a second conductive component 105.

Wherein, the first conductive component 104 is disposed opposite to the second conductive component 105 and constitutes a sensing capacitor Cx. In this embodiment, the first conductive component 104 and the second conductive component 105 are both made of metal conductive materials, and are both semi-circular flat plate structures with a gap at the center of the circle, and the first conductive component 104 and the second conductive component 105 are arranged in parallel .

The elastic sensing element 100 is used to sense the bending state of the flexible display body FB, that is, the elastic sensing component 100 is synchronized with the flat state and the bending state of the flexible display body FB. In this embodiment, the elastic sensing element 100 is extended in the flexible display body FB along the bending direction of the flexible display body FB, that is, the first direction F1, so that when the flexible display body FB is in a straight state, The sexy sensing element 100 is in a straight state; when the flexible display body FB is in a curved state, the elastic sensing element 100 is also in a curved state simultaneously, and the bending degree of the elastic sensing element 110 is the same as that of the flexible display screen FB.

Preferably, the elastic sensing element 100 is a flexible link or a spring, and at the same time, the elastic sensing element 100 can be all fixed on the flexible display body FB along the first direction F1 and one end is movably connected to the first conductive component 104 Or, one end of the elastic sensing element 100 is fixed on the flexible display body FB, and the other end is movably connected to the first conductive component 104. Preferably, the end of the elastic sensing element 100 connected to the conductive component 104 has a through hole (not marked).

Preferably, the flexible display main body FB is provided with a concave accommodating track (not shown) corresponding to the position of the elastic sensing element 100, that is, the elastic sensing element 100 is disposed in the accommodating track, so that It is ensured that the bending direction of the elastic sensing element 100 when the flexible display main body FB is bent is consistent with the bending direction of the flexible display main body FB.

When the flexible display main body FB is bent, the elastic sensing element 100 follows the bending of the flexible display main body FB and drives the first conductive component 104 to move relative to the second conductive component 105 to change the sensing capacitance Cx Of the capacitor.

Specifically, the elastic sensing element 100 is connected to the first conductive component 104, and when the flexible sensing element 100 bends with the flexible display body FB, the first conductive component 104 is driven to rotate around the first pivot 103. The position of the second conductive component 105 is fixed relative to the first pivot 103, that is, the positions of the second conductive component 105 and the first pivot 103 are fixed. When the first conductive component 104 rotates around the first pivot 103, the first conductive component 104 moves relative to the second conductive component 105, thereby changing the area facing the two and also causing the capacitance value of the sensing capacitor Cx Corresponding changes also occur in real time.

Please refer to FIGS. 3-5 together, wherein FIG. 3 is an enlarged schematic structural view of a part of the bending detection device shown in FIG. 2, FIG. 4 is a perspective structural schematic view of the bending detection device shown in FIG. 1, and FIG. 5 is shown in FIG. A schematic diagram showing the exploded structure of the bending detection device.

As shown in FIGS. 3-5, the bending detection module 10 further includes a second pivot 101 and a first cantilever 102, and the elastic sensing element 100 is fixed to the second pivot 101 through the through hole along the first direction F1. That is, the second pivot 101 passes through the through hole of the elastic sensing element 100 to achieve the fixed connection between the elastic sensing element 100 and the second pivot 101.

The first cantilever 102 includes an opposite first end 102a and a second end 102b, wherein the first end 102a has a first connection portion 1021, the second end 102b has a second connection portion 1022, and the first connection portion 1021 is connected to the second The parts 1022 are all hollow cylindrical structures. The first connecting portion 1021 is pivotally connected to the second pivot 101, that is, the first connecting portion 1021 is sleeved on the second pivot 101 by a hollow cylindrical structure, or the second pivot 101 penetrates the first connecting portion 1021 Hollow cylindrical structure. Wherein, the first cantilever 102 can rotate around the second pivot 101 through the first connecting portion 1021 under the driving of external force. Meanwhile, the second connection portion 1022 of the first cantilever 102 is fixedly connected to the first conductive component 104, that is, the second connection portion 1022 of the first cantilever 102 is fixedly connected to the first conductive component 104, and relative rotation does not occur. In this embodiment, the second direction F2 is different from the first direction F1.

When the elastic sensing element 100 deforms and bends, the second pivot 101 and the first cantilever 102 are displaced along the deformation direction, and at the same time, the first cantilever 102 is driven relative to the second pivot by the second pivot 101 101 rotates, and when the first cantilever 102 rotates, it drives the first conductive component 104 to rotate around the first pivot 103.

In this embodiment, the bending detection module 10 includes two first cantilevers 102 spaced apart by a predetermined distance. The first conductive component 104 is sandwiched between the two first cantilevers 102; the elastic detection element 100 is sandwiched between the two first cantilevers 102, and at the same time, the second pivot 101 passes through the first of the two first cantilevers 102 The connection portion 1021 and the elasticity detection element 100.

Preferably, the second pivot 101 is integrated with the first cantilever 102 and the first conductive component 104 into an integrated structure.

Alternatively, in other embodiments of the present invention, the folding detection module 10 may include only one first cantilever 102.

Please refer to FIG. 6, which is a three-dimensional structural diagram of the first conductive component shown in FIG. 2. The first conductive component 104 further includes a limiting portion 104a. The first conductive component 104 is connected to the second connecting portion 1022 of the first cantilever 102 through the limiting portion 104a, and is used to define the first conductive group 104 relative to The position of the first cantilever 102.

Specifically, the limiting portion 104a includes a circular hollow through portion 104b and a limiting rib 104c, wherein the first pivot 103 passes through the hollow portion in the through portion 104b, so that the first conductive component 104 can surround the first The pivot 103 rotates.

The limiting rib 104c is elongated and protrudingly arranged on the outer surface of the penetrating portion 104, and the limiting rib 104c is locked in the second connecting portion 1022 of the first cantilever 102, thereby defining the first conductive component 104 and the first cantilever The relative position of 102 is fixed to prevent the first conductive component 104 from moving relative to the first cantilever 102. It can be understood that, corresponding to the limiting rib 104c, the hollow portion of the second connecting portion 1022 has a corresponding groove structure, and when the second connecting portion 1022 is connected to the first conductive component 104, the limiting rib 104c is correspondingly locked to the second connecting portion The position of the groove in 1022 makes the position of the second connection portion 1022 and the first conductive component 104 relatively fixed without relative displacement.

Please refer to FIGS. 7 and 8. FIG. 7 is a schematic side view of the flexible display device shown in FIG. 1 when it is bent, and FIG. 8 is a side view of the bending detection device shown in FIG. 1 when it is not bent and when it is bent. The schematic diagram illustrates the corresponding relationship between the bending state of the flexible display main body FB and the change in the capacitance value of the sensing capacitor Cx with reference to FIGS. 1 and 7-8.

As shown in FIGS. 1 and 8, when the flexible display main body FB is not bent, the first conductive component 104 and the second conductive component 105 are arranged directly around the first pivot 103, and the first conductive component 104 and the second conductive member 105 have an area A1 (hatched by hatching).

Among them, the calculation formula of capacitance is: C=ε*ε0*A/d, where ε is the relative dielectric constant between the plates, ε0 vacuum dielectric constant, A is the area between the two electrode plates, d is The distance between the two plates. It can be seen from the calculation formula of the capacitance in combination with this embodiment, that the environment where the first conductive component 104 and the second conductive component as two plates are located (ε*ε0) and the distance between them (d) remain unchanged, the two When the area (A) facing each electrode plate changes, the capacitance value C as the sensing capacitance Cx changes accordingly.

At this time, the sensing capacitance Cx formed by the first conductive element 104 and the second conductive element 105 has a first capacitance value C0.

As shown in FIGS. 7-8, when the flexible display main body FB is bent, the first conductive component 104 rotates relative to the second conductive component 105 about the first pivot 103 to produce relative motion. The facing area S1 of the second conductive element 105 is changed to A1-ΔA, according to the formula of the capacitance, and the sensing capacitance Cx correspondingly has the second capacitance value C0-ΔC.

It can be seen that the bending state of the flexible display body FB is characterized by the capacitance value through the bending detection module 10 in the bending detection device CD, that is, the bending detection module 10 can The bending state is converted into the capacitance value corresponding to the sensing capacitor Cx. Then, by identifying the change in the capacitance value of the sensing capacitor Cx, it can be identified whether the flexible display main body FB is bent and the degree of the bending.

In other modified embodiments of the present invention, if the flexible display body FB changes from a flat non-bent state to a bent state, the corresponding elastic detection element 100 drives the first conductive component 104 to move such that the sensing capacitance Cx The facing area A of the two middle plates changes from small to large, that is, the facing area changes from A1 to A1+ΔA, and the capacitance value of the sensing capacitor Cx changes from C0 to C0-+ΔC.

Please refer to FIG. 9, which is a block diagram of a circuit structure of a bending recognition circuit. As shown in FIG. 9, the bending recognition circuit 12 is electrically connected to the sensing capacitor Cx for detecting the amount of change in the capacitance value of the sensing capacitor Cx and identifying the bending of the flexible display body FB Fold state.

In this embodiment, the bend recognition circuit 12 uses the form of a frequency-modulated measurement circuit to recognize the amount of change formed when the capacitance value of the sensing capacitor Cx changes, that is, the bend recognition circuit 12 will change the capacitance value of the sensing capacitor Cx And the amount of change is converted into a change in the frequency of the oscillator, and then the frequency change of the oscillator is converted into a change in the corresponding voltage. At the same time, the change in the voltage value and the amount of change can know whether the flexible display main body FB is bent or not. Degree.

Specifically, the bending recognition circuit includes an oscillation inductance L, an oscillator 121, a limiting amplifier 122, and a frequency discriminator 123.

The oscillation capacitor L is electrically connected to the two poles of the sensing capacitor Cx, that is, the first conductive element 104 and the second conductive element 105 that are electrically connected to the two poles of the sensing capacitor Cx. In this embodiment, the sensing capacitor Cx and the oscillation inductance L are connected in parallel with each other.

The oscillator 121 is electrically connected to the oscillating inductance L. The sensing capacitor Cx and the oscillating inductance L are used as the oscillator 121 as part of the resonant circuit of the oscillator 121. When the capacitance value of the sensing capacitor Cx changes, the frequency of the oscillator occurs Variety.

Specifically, the corresponding relationship between the frequency f of the oscillator 121 and the sensing capacitance Cx is:

C1 is the inherent capacitance value of the oscillator;

C2 is the distributed capacitance value of the oscillator;

Cx is the capacitance value of the sensing capacitor Cx.

In this way, when the flexible display body FB is in an unbent state, such as a flat state, the frequency of the oscillator 121

When the flexible display body FB is in a bent state, the frequency of the oscillator 121

Among them, △C represents the amount of change in capacitance.

The oscillator 121 outputs a frequency signal corresponding to the sensing capacitor Cx.

The limiting amplifier 122 is electrically connected to the oscillator 121 and is used to amplify the frequency signal contained in the oscillator 121.

The frequency discriminator 123 is electrically connected to the limiting amplifier 122 and used for converting the frequency signal into a voltage signal. Among them, please refer to FIG. 10 for the corresponding relationship between the voltage signal output by the frequency discriminator 123 and the frequency signal. FIG. 10 is a graph showing the relationship between the frequency (abscissa, f) change of the oscillator 121 and the voltage (ordinate, u) coordinate, as shown in FIG. 10 As shown, when the sensing capacitance Cx changes by the change amount ΔC, the frequency of the oscillator 121 will correspondingly change by Δf, so that the voltage will also change correspondingly by ΔU.

In this way, the bending state of the flexible display main body FB can be known by the change of ΔU in the acquired voltage signal, that is, whether the flexible display main body FB is bent and the degree of bending can be accurately known.

It can be understood that, in other real-time modes of the present invention, the first conductive component 104 and the second conductive component 105 constituting the sensing capacitor Cx may also have other shapes according to actual needs, such as a circular ring, cylindrical, rectangular, etc., and Not limited to this.

Compared with the prior art, the bending detection device CD has a compact structure, and can accurately recognize the bending state of the flexible display main body FB, thereby facilitating the flexible display device FD to execute subsequent other instructions according to the bending state, such as executing extinction Screen, image segmentation, etc.

This article uses specific examples to explain the principles and implementation of the present invention. The descriptions of the above examples are only used to help understand the core idea of the present invention. At the same time, for those of ordinary skill in the art, based on the idea of the present invention, There will be changes in the specific implementation and the scope of application. In summary, the content of this specification should not be construed as limiting the present invention.

Claims

A bending detection device for detecting the bending state of the main body of a flexible display screen, characterized in that it includes:

The bending detection module includes an elastic sensing element, a first conductive component and a second conductive component, wherein the first conductive component is disposed opposite to the second conductive component and constitutes a sensing capacitor, and the elastic sensing element is located in the When the main body of the flexible display screen is bent, the first conductive component is driven to move relative to the second conductive component, and the capacitance of the sensing capacitor varies with the first conductive component relative to the second conductive component Changes in the relative motion produced;

The bending recognition circuit is electrically connected to the sensing capacitor, and is used for detecting the change amount of the capacitance value of the sensing capacitor and identifying the bending state of the flexible display body according to the change amount of the capacitance value.
The bend detection device according to claim 1, wherein the elastic sensing element is disposed in a direction in which the flexible display body bends.
The bending detection device according to claim 2, wherein the first conductive component is rotatably connected to the first pivot, the elastic sensing element is connected to the first conductive component, and the elastic The bending of the sensing element with the main body of the flexible display screen drives the first conductive component to rotate about the first pivot, so that the first conductive component moves relative to the second electric component.
The bending detection device according to claim 3, wherein the second conductive component is fixed at a position directly opposite to the first conductive component relative to the first pivot, when the flexible display body When no bending occurs, the first conductive component is completely opposite to the second conductive component; when the flexible display body is bent, the first conductive component is wound relative to the second conductive component The first pivot rotates and changes the area where the first conductive component and the second conductive component are facing each other and changes the capacitance value of the sensing capacitor.
The bending detection device according to claim 4, wherein the bending detection module further comprises a second pivot and a first cantilever, and the elastic sensing element is fixed on the second pivot , The first end of the first cantilever is rotatably connected to the second pivot, the second end of the first cantilever is fixedly connected to the first conductive component, when the elastic sensing element is in the When the main body of the flexible display screen bends, the second pivot is driven to move along the bending direction, and the first end of the first cantilever rotates around the second pivot to drive the first conductive component Rotate about the first pivot.
The bending detection device according to claim 5, wherein the first end has a first connection portion, the second end has a second connection portion, and both the first connection portion and the second connection portion are hollow Cylindrical structure.
The bending detection device according to claim 6, wherein the first conductive component further comprises a limiting portion, and the first conductive component is fixedly connected to the first cantilever through the limiting portion Two connecting portions, the limiting portion cooperates with the second connecting portion to define a position of the first conductive component relative to the first cantilever.
The bend detection device according to claim 1, wherein the bend recognition circuit includes an oscillating inductance, an oscillator and a frequency discriminator, the oscillating inductance is in parallel with the sensing capacitance, and the oscillator Electrically connected to the oscillating inductance and the sensing capacitor for sensing a change in the capacitance value of the sensing capacitor and outputting a corresponding frequency signal, the oscillating inductance and the sensing capacitor serving as the oscillation In a part of the resonator resonant circuit, the frequency signal changes corresponding to the change in the capacitance value of the sensing capacitor, and the frequency discriminator is electrically connected to the oscillator and used to convert the frequency signal into a voltage signal.
The bend detection device according to claim 8, wherein the bend recognition circuit further includes a limiting amplifier, the limiting amplifier is electrically connected between the oscillator and the frequency discriminator, It is used for performing amplification processing on the frequency signal, and transmitting the amplified frequency signal to the frequency discriminator.
A flexible display device includes a flexible display screen main body and a bending detection device according to any one of claims 1-9, and the elastic sensing element is arranged along a direction in which the flexible display screen main body bends. The first conductive component and the second conductive component are disposed on the edge of the flexible display screen.