KR20180035965A - Touch display apparatus and touch-performance maintaining method - Google Patents

Abstract

In a force touch type display device of a method for cutting a part of a cover bottom which is a rear supporting structure of a display panel, embodiments of the present invention can uniformly maintain an air gap which is a gap between both electrodes and secure uniform force touch performance by arranging an adhesive member for maintaining the gap between the outer surface of the cover bottom of a display module and the inner surface of a mid-frame of a set device and providing a function for correcting force calibration data after the impact/vibration test of the touch display device.

Description

TECHNICAL FIELD [0001] The present invention relates to a touch display device and a touch performance maintaining method.

The embodiments relate to a touch display device and a touch performance maintaining method thereof.

BACKGROUND ART [0002] As an information-oriented society develops, there have been various demands for display devices for displaying images, and various types of display devices such as a liquid crystal display device, a plasma display device, and an organic light emitting display device have been utilized.

Of these display devices, mobile devices such as smart phones and tablets, and medium and large-sized devices such as smart TVs, etc., provide touch-based input processing in accordance with user convenience and device characteristics.

Such a display device capable of input processing of a touch method has been developed to provide a variety of functions, and user demands are also diversified.

However, the currently applied touch-type input processing is a method of sensing only a user's touch position (touch coordinates) and performing related input processing at a sensed touch position, and it provides various functions of various types in various forms There is a limit to the present situation in which the needs of various users must be met.

It is an object of the embodiments of the present invention to provide a touch display device capable of sensing a touch position by sensing a touch force corresponding to a force of a user pressing the screen when touching.

Another object of the present invention is to provide a display device which senses a touch force corresponding to a pressing force of a screen when a user touched the touch screen by uniformly maintaining an air gap which is a gap between both electrodes, Which is capable of securing a touch panel.

Another object of these embodiments is to provide a gap holding adhesive member between the outer surface of the cover bottom of the display module and the mid frame of the setting device in the force-touched display device so that the gap between the two electrodes for force- Touch display device capable of maintaining a high-speed display.

Another object of the present invention is to provide a touch performance maintaining method capable of maintaining the same force touch performance before and after the vibration / impact test by correcting the force calibration data after the shock / vibration test of the touch display device .

In one aspect, the embodiments include a cut cover bottom (first support portion) supporting only an edge region of a display panel including a first electrode for touch sensing, a midframe covering the entire rear surface of the display panel And a supporting portion), wherein a gap holding adhesive member is disposed between the cut cover bottom and the mid frame.

The gap holding adhesive member may be composed of a nonconductive material including a first bonding surface bonded to the outer surface of the cut cover bottom and a second bonding surface bonded to the inner surface of the midframe, have.

In addition, the touch driver may include a configuration in which one of the cover bottom and the mid frame, which is cut according to the force touch sensing position, is selected as the second electrode to apply the second electrode driving signal GND. More specifically, In the case of sensing the touch pressure in the center area A1 of the first electrode where the cut cover bottom does not overlap, the mid frame is selected as the second electrode, and the edge area A2 of the first electrode partially overlapped with the cut cover bottom When the touch pressure is sensed, the ground signal may be applied by selecting the cut cover bottom as the second electrode.

A method of holding a touch performance of a touch display device in a display device including the gap holding adhesive member includes the steps of applying a touch driving signal to the second electrode, A function of measuring an inductive signal induced at the first electrode by a signal, comparing the measured induction signal with a plurality of pre-stored standard values, and compensating the force touch calibration data for the first electrode according to the comparison result .

At this time, before applying the touch driving signal, the plurality of touch electrode blocks constituting the first electrode are pressed with a constant pressure, and the capacitance value is measured for each touch electrode block, and the capacitance value of the measured touch electrode block is The force touch calibration process can be further standardized.

The step of measuring the induction signal and the step of compensating the force touch calibration data may be performed for each of the plurality of touch electrode blocks constituting the first electrode.

The reference value is a lookup table prepared for each display device before the vibration / impact test. The reference value includes a reference value of an induced signal according to a change amount of a gap between a cover bottom (first support portion) and a second support portion Lt; / RTI >

According to the embodiments of the present invention, it is possible to provide a force-touch-type display device capable of sensing a touch position by sensing a touch force corresponding to a force pressing the screen when the user touches the touch screen.

In particular, the thickness of the force-touch type display device can be reduced by using a structure in which the cover bottom constituting the display module is cut so as to cover only the edge area without covering the entire rear surface of the display device.

In addition, in the display device which senses a touch force corresponding to the force pressing the screen when the user touches, by arranging a gap holding adhesive member between the outer surface of the cover bottom of the display module and the inner surface of the mid frame of the setting device, It is possible to uniformly maintain an air gap which is a gap between both electrodes, thereby ensuring a uniform force touch performance.

Further, by correcting the force calibration data after the shock / vibration test of the touch display device, it is possible to maintain the same force touch performance before and after the vibration / impact test.

1 and 2 are views showing a schematic configuration of a force-touch type display device.
3 is a cross-sectional view of a force-touch type display device.
4 is a view illustrating a situation in which a gap is changed in a force-touch-type display device and a principle of sensing a force-touch according to the gap.
5 and 6 illustrate various methods of constructing the first electrode and the second electrode for force touch sensing in the force-touch type display device.
Fig. 7 shows a cross-sectional structure of a force-touch type display device of a cover bottom cutting structure to which this embodiment can be applied.
FIG. 8 is a plan view showing the arrangement of the first electrodes of the force-touched display device according to the present embodiment, in which the center region where the first electrode does not overlap the cover bottom and the edge region where the first electrode overlaps the cover bottom .
9 is a cross-sectional view of the force-touch type display device according to the present embodiment, in which the touch control unit has a configuration for switching the second electrode when the force touch of the center region and the edge region is sensed, And a bonding member for bonding is disposed.
10 shows an example of the arrangement of the first electrodes of the force-touch type display device according to the present embodiment, in which two touch electrode groups are symmetrically arranged, and each of the touch electrode groups has k (k = 9 ) Number of touch electrode blocks.
11 shows a flow of the force touch performance checking method of the touch display apparatus according to the present embodiment.
FIG. 12 shows an overall flow of a touch performance maintenance method including an automatic baseline tracking process for correcting force calibration data after a vibration / impact test.
FIG. 13 shows a detailed flow of an automatic baseline tracking process for correcting force calibration data after a vibration / impact test.

Hereinafter, some embodiments of the present invention will be described in detail with reference to exemplary drawings. In the drawings, like reference numerals are used to denote like elements throughout the drawings, even if they are shown on different drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

In describing the components of the present invention, terms such as first, second, A, B, (a), and (b) may be used. These terms are intended to distinguish the components from other components, and the terms do not limit the nature, order, order, or number of the components. When a component is described as being "connected", "coupled", or "connected" to another component, the component may be directly connected or connected to the other component, Quot; intervening "or that each component may be" connected, "" coupled, "or " connected" through other components.

1 and 2 are views showing a schematic configuration of a force-touch type display device.

1, the force-touch type touch display device 100 includes a plurality of first electrodes E1 for sensing the presence or absence of touch by a user and a touch position (touch coordinates), a touch force of a user, A display panel 110 in which a plurality of first electrodes E1 are embedded and a driving circuit for driving the plurality of first electrodes E1 and second electrodes E2, And a gap structure unit 130 for maintaining a gap between the first electrode E1 and the second electrode E2.

The touch-type touch display device 100 may operate in a display mode for displaying an image or may operate in a touch mode for sensing a user's touch (presence / absence of touch, touch position, touch force).

When the touch display device 100 operates in the display mode, the data lines and gate lines disposed on the display panel 110 are driven to display an image.

At this time, a plurality of first electrodes E1 embedded in the display panel 110 are applied with a display driving voltage for displaying an image. That is, the plurality of first electrodes E1 serve as electrodes for display driving in the display mode period.

Specifically, the first electrode E1 is simultaneously used as a common electrode function for applying the common voltage Vcom to the pixel and a touch electrode for touch recognition.

When the touch display device 100 operates in the touch mode, it may sense the touch position (touch coordinates) of the user or may sense the touch force of the user.

That is, the touch sensing may include two modes. Firstly, the touch position is sensed by measuring the self-capacitance at the first electrode after applying the touch driving signal DS to the first electrode. For convenience, this first touch sensing is referred to as an in-cell touch mode or an in-cell touch operation.

In the second touch method, a first electrode driving signal DS1 and a second electrode driving signal DS2 are applied to the first electrode and the second electrode, respectively, and then a gap between the first electrode and the second electrode The touch position is recognized by measuring the capacitance change between both electrodes which is generated when the gap is changed. For convenience, the second touch method is referred to as force touch mode or force touch operation.

That is, in the in-cell touch mode, the driving circuit 120 sequentially applies the first electrode driving signal DS1 to the plurality of first electrodes E1 during a constant in-cell touch driving period, and the self- And senses the touch position (touch coordinates) of the user.

Also, during a constant force touch driving period, the driving circuit 120 applies the first electrode driving signal DS1 to the first electrodes E1 and the second electrode driving signal to the second electrode E2 Sensing the user's touch force.

The touch-type touch display apparatus 100 is configured to display a user's vertical load using a change in gap between the first electrode E1 and the second electrode E2 when a user's vertical load is applied to the display panel 110 Sensing Touch Force.

That is, the capacitance between both electrodes is measured in the state that different driving signals (DS1, DS2) are applied to the first electrode and the second electrode, and when the user touches the gap, The change of the capacitance occurs, and the touch position is determined by detecting the change of the capacitance.

Therefore, a gap must exist between a plurality of first electrodes E1 built in the display panel 110 and a second electrode E2 located outside the display panel 110. In order to maintain such a gap, The gap structure unit 130 may be disposed between the first electrode E1 and the second electrode E2.

That is, it is possible to change the size of the gap between the first electrode E1 and the second electrode E2 when the touch of the user is generated through the gap structure unit 130, Not only the user's touch position (touch coordinates) but also the touch force can be sensed.

Hereinafter, a more detailed structure of the force-touch type touch display device 100 to which the present embodiment can be applied will be described with reference to FIG.

Referring to FIG. 2, the touch display panel 110 of the touch display device 100 according to the present embodiment includes a first substrate 111 on which a thin film transistor (TFT) And a second substrate 112 on which a CF (Color Filter) or the like is disposed.

The driving chip 140 may be mounted, bonded, or connected to the non-active area N / A of the first substrate 111.

Here, the driving chip 140 may be a chip implementing all or a part of the driving circuit 120, a data driving chip, or a display driving chip including all or a part of the driving circuit 120 and the data driving chip have.

The data driving chip may be represented by a D-IC. The data driving chip includes a data driver for applying a data signal to a data line of a display panel to control a display, and a touch driver for applying a touch driving signal to the touch electrode. And a touch driver for recognizing the touch panel.

However, the touch driver is not necessarily included in the data driver chip, and may be provided separately from the data driver.

The lower structure 131 may be positioned below the display panel 110 and the second electrode E2 may be positioned below or inside the lower structure 131. [

The lower structure 131 may be, for example, a backlight unit of a liquid crystal display device.

In this case, the second electrode E2 may be positioned under the backlight unit. Thus, the second electrode E2 can be disposed without interfering with the light irradiation function of the back light unit.

The gap structure unit 130 may be located at the bottom, inside or at the side of the lower structure 131. In addition, the second electrode E2 may be located under the gap structure unit 130 or inside thereof.

The position of the second electrode E2 or the position of the gap structure unit 130 may be variously designed so that the display panel 110 and the touch force suitable for the design structure of the touch display device 100 Force sensing structure, which will be described in more detail below with reference to FIGS. 5 and 6. FIG.

Hereinafter, a method of sensing the touch position (touch coordinates) and the touch force of the user of the force-touch-type display device 100 will be described with reference to FIGS. 3 and 4. For convenience of explanation, A case where the touch display device 100 according to the embodiments is a liquid crystal display device will be described as an example.

FIG. 3 is a cross-sectional view of the force-touch type touch display device 100. FIG. 4 is a cross-sectional view of a force-touch type touch display device 100 according to a first embodiment of the present invention. E2) in the first embodiment are changed.

3, the display panel 110 of the touch display device 100 includes a first polarizer 310, a first substrate 111, a plurality of first electrodes E1, a second substrate 112, A second polarizing plate 320, and the like.

A bonding layer 330 and an upper cover 340 are disposed on the display panel 110.

The touch display apparatus 100 applies the first electrode driving signal DS1 to a plurality of first electrodes E1 in an in-cell touch operation period using only the first electrode in the touch mode.

When the touch of the user is generated, a change in the magnitude of the self-capacitance (SC) between the pointer, such as a user's finger, and the first electrodes E1 is sensed to sense the touch position of the user.

The touch display apparatus 100 applies a first electrode driving signal DS1 to a plurality of first electrodes E1 during a force touch operation period for sensing a touch force of a user during a touch mode, And applies the second electrode driving signal DS2 to the second electrode E2.

At this time, the second electrode driving signal DS2 applied to the second electrode E2 may be a ground voltage signal.

The change of the mutual capacitance (MC) according to the change of the gap G between the first electrode E1 and the second electrode E2 when the vertical load is generated by the touch of the user is sensed, Sensing the user's touch force.

That is, at the time of the in-cell touch operation, the touch position (touch coordinates) is sensed by sensing the change of the self capacitance (SC) generated at the first electrode at the time of touch generation by the user, Sensing the touch force through sensing the change of the mutual capacitance MC between the second electrodes.

For this purpose, in order for the force touch to operate, a gap is formed between the first electrode E1 and the second electrode E2 so that a change in the mutual capacitance MC between the first electrode and the second electrode may occur. (G) should be formed.

Referring to FIG. 4, when a vertical load is generated by a user's touch, the upper cover 340, the display panel 110, and the like are slightly bent downward.

Accordingly, the size of the gap G such as an air gap or a dielectric gap existing between the first electrode E1 and the second electrode E2 can be changed.

As shown in FIG. 4, when the gap G is G1 before the vertical load is generated by the user's touch, and the gap G after the vertical load due to the touch of the user is G2, G2 becomes smaller than G1.

The gap G between the first electrode E1 and the second electrode E2 is reduced from G1 to G2 due to the vertical load caused by the touch of the user so that the mutual capacitance MC And the user's touch force can be sensed.

Meanwhile, the second electrode E2 for sensing a touch force of the user may be added to the touch display device 100 for sensing a touch force. However, in the touch display device 100, The second electrode E2 may be used as the second electrode E2.

For example, the back cover of the back light unit included in the liquid crystal display device can be used as the second electrode E2 to sense the touch force of the user.

5 and 6 illustrate various methods of constructing the first electrode and the second electrode for force touch sensing in the force-touch type display device.

The term "display device" is used herein to refer not only to a display device such as a liquid crystal module (LCM) including a display panel and a driver for driving the display panel, but also to a notebook Such as a computer, a television, a computer monitor, a mobile electronic device such as a smart phone or an electronic pad, and the like.

In particular, in the present specification, a display device of a narrow sense including a display panel and a supporting structure for supporting a driving part for controlling touch and image display of the display panel and a display panel thereof is expressed as a 'display module' A set electronic device as a finished product is expressed as a 'set device' or a 'display device'.

5 and 6, a liquid crystal display panel 510, a backlight unit 520 for providing a backlight to the liquid crystal display panel 510, and a cover bottom 530 as a supporting structure for supporting the back surface of the backlight unit are formed as a liquid crystal display module And a finished device including a cover glass 540 for protecting the front surface of the liquid crystal display panel and a mid frame 550 for supporting the entire set device supporting the rear of the liquid crystal display module can be referred to as a ' Display device '.

5, the cover bottom 530 of the liquid crystal display module LCM is used as the second electrode for the force touch.

That is, a first electrode 512, which is a touch electrode used as a common electrode, is disposed in the liquid crystal display panel 510, and the first electrode is used as a touch electrode in an in- And is used as a touch electrode corresponding to the second electrode during operation.

5, the cover bottom 530 of the liquid crystal display module is used as a second electrode for the force touch, and the ground signal, which is the second electrode driving signal DS2, may be input to the cover bottom.

5, the first electrode driving signal DS1 is applied to the first electrode 512 disposed inside the liquid crystal display panel, and the second electrode driving signal DS1 is applied to the cover bottom 530 used as the second electrode. And detects a force touch in a state where a ground (GND) signal is applied as a two-electrode driving signal.

For this purpose, a gap, which is a space for force touch sensing, should be formed between the first electrode 512 and the cover bottom 530 as a second electrode, and a liquid crystal display panel 510 including a first electrode, (530) may be used as such a gap.

Particularly, the force touch sensing needs to be a gap that can be varied by the pressing pressure of the user. Therefore, the backlight unit as a fixture disposed between the first electrode and the second electrode can not be used as a gap structure, A first air gap AG1 having a variable gap is formed between the rear surface of the backlight unit 510 and the backlight unit 520.

5, a first electrode in the display panel and a second electrode in the cover bottom are used, and a variable gap in between the back surface of the liquid crystal display panel 510 and the backlight unit 520 1 force touch is sensed by measuring the change of the first capacitance C1 between the electrodes in accordance with the change of the air gap AG1.

5, the force-touch type display device includes a cover glass 540 for protecting the front surface of the liquid crystal display panel separately from the liquid crystal display module described above, and a cover glass 540 for supporting the entire rear surface of the liquid crystal display module. Frame 550, but this midframe 550 is a part independent of force-touch sensing.

6 is a cross-sectional view of another type of force-touched display device in which a separate cover bottom is not used.

 In the structure of Fig. 6, the cover bottom, which is the rear supporting structure of the liquid crystal display module, is not used, and the mid frame, which is the rear structure of the setting apparatus, is disposed directly behind the backlight unit.

6, the midframe 550 functions as a second electrode, a second air gap AG2 is formed between the backlight unit 520 and the midframe 550, The size of the second air gap AG2 is changed during the operation so that the force touch can be recognized.

That is, the first electrode driving signal is applied to the first electrode 512 disposed inside the liquid crystal display panel 510, and the ground signal, which is the second electrode driving signal, is applied to the mid frame 550, which is the second electrode The second capacitance C2 between the first electrode and the second electrode changes in accordance with the size change of the second air gap AG2 in the presence of the user's touch pressure. By measuring the change in the second capacitance (C2), the position of the force touch can be recognized.

On the other hand, the force touch type display device having the structure as shown in FIGS. 5 and 6 has the following disadvantages.

As shown in FIG. 5, in the structure using the cover bottom of the display module as the second electrode, the cover bottom may be bent or twisted during use, which may lower the force touch performance.

In addition, since the first air gap AG1 must be provided between the liquid crystal display panel 510 and the backlight unit 520, there is a problem that the thickness of the entire display device increases.

On the other hand, in the structure using the midframe 550 of the curler as the second electrode as shown in FIG. 6, it is not applicable to a display device without a cover bottom.

That is, since a display module is usually manufactured separately and delivered to an end-product manufacturer, in order to apply the force-touch type display device as shown in FIG. 6, a manufacturer of a display module must manufacture and supply a display module without a cover bottom.

However, since the display module without a cover bottom may have damage to the module during transportation after its manufacture, the structure is not widely used, and thus a force-touch type display device as shown in Fig. 6 can not be universally applied It is.

In order to overcome such a problem, a cover-bottom cutting type force-touch type display device which removes a part of the cover bottom as shown in Fig. 7 can be proposed.

Fig. 7 shows a cross-sectional structure of a force-touch type display device of a cover bottom cutting structure to which this embodiment can be applied.

8 is a plan view showing the arrangement of the first electrodes of the force-touched display device according to the present embodiment.

As shown in Fig. 7, the cover-bottom cut type force-touched display device has a structure taking advantage of the structure of Figs. 5 and 6, in which the display module includes a cover bottom, And the midframe of the set device is used as the second electrode.

7, the force-touched display device includes a display panel 710 including a first electrode 712 therein, a backlight unit 720 providing light to the display panel, A cover glass 740 disposed in front of the display panel, and a cover glass 740 connected to the display device (set device) 740. The cover glass 740 is disposed in front of the display panel and includes a cutting cover bottom 730 for removing only the edge area of the backlight unit. And a mid-frame 750 which is formed as a whole rear surface structure.

At this time, the midframe 750 becomes the second electrode and the ground signal is applied.

A second air gap AG2 defined as a space between the rear surface of the backlight unit and the midframe is defined in the central region of the removed cover bottom.

During the force touch operation period, the first electrode driving signal is applied to the first electrode 712, and the ground signal, which is the second electrode driving signal, is applied to the mid frame 750, which is the second electrode.

In this state, when the user's touch pressure is applied, the gap of the second air gap AG2 is changed at that position, and thus the second capacitance C2 between the first electrode and the second electrode is changed, 2 capacitance C2, it is possible to sense the force touch position.

7 can overcome the disadvantages of the structures of FIGS. 5 and 6, but the cover bottom overlaps with a part of the active area A / A of the display panel, There is a problem in that the force touch performance is different from the central area A1 in which the cover bottom is not present in the overlap area.

As shown in FIG. 8, the first electrode of the force-touch type display device according to the present embodiment includes a central region A1 in which the first electrode does not overlap with the cover bottom, and a central region A1 in which the first electrode overlaps the cover bottom And an edge area A2.

That is, the first electrode is arranged such that a total of M * N touch electrodes are disposed, and one line of touch electrodes disposed at the edges of the entire touch area overlaps with a part of the cut cover bottom part . At this time, the cut cover bottom may be overlapped only with a part of one line of touch electrodes (that is, the outermost touch electrode block) disposed at the edge, and one line of touch electrodes , And the outermost touch electrode block).

In such a structure, as shown in the enlarged view of FIG. 7B, force touch detection can be performed as desired in the central area A1 where the cover bottom is removed, but a part of the edge area A1 where the cut cover bottom is left And a cover bottom of a metal material exists between the mid-frame 750 and the first electrode, which is the second electrode, in the overlapped area, so that desired force touch performance can not be secured .

That is, not only the distance of the air gap between the first electrode and the second electrode (midframe) is different in the edge region A2, but also the cutting cover bottom of the metal is disposed between the electrodes to function as a kind of shielding layer, It is impossible to measure a change in capacitance of the capacitor.

As a result, in the structure as shown in FIG. 7, there is a limit in that the force touch can not be detected in the area where the cut cover bottom touches the display area A / A.

7, the cutting cover bottom 730 and the midframe 750 are spaced apart from each other with a gap G between them. When the vibration / impact test is performed in this state or the display device is used for a long time , The clearance between the cutting cover bottom and the midframe may be different from the original, and the force touch performance may be weakened accordingly.

7, the midframe 750 is adhered and fixed only to the edge region of the cover glass 740 of the display device. Since the adhesion region is narrow, the midframe 750 is likely to fall off, and the midframe 750 is formed of a thin metal There is a high possibility that warpage will occur due to long use or impact.

Therefore, the gap G between the cover bottom 730 and the midframe 750 cut by the adhesion failure or the impact can be changed, and such a change in the gap G can result in the second air gap AG2 required for the force touch, And the performance of the force touch can not be maintained.

10, the display device is subjected to a process of normalizing a second capacitance measured for each touch electrode (block) after fabrication, that is, a force touch calibration process, and thereafter, a shock / vibration test And then re-evaluating the force touch performance.

In this force touch calibration process and vibration / impact test process, if the amount of change of the gap G between the cover bottom and the mid frame is out of a predetermined threshold value, the force touch reevaluation process can not be performed smoothly.

Accordingly, in the present embodiment, by proposing an auto baseline tracking method as a non-touch type touch performance holding method, it is possible to maintain the force touch performance, and as a prerequisite for performing such a touch performance holding method There is proposed a method of disposing a gap holding adhesive member between the cover crotch and the midframe so as to keep the amount of change in gap between the cover butter and the midframe below the threshold value.

9 is a cross-sectional view of the force-touch type display device according to the present embodiment, in which the touch control unit has a configuration for switching the second electrode when the force touch of the center region and the edge region is sensed, And a bonding member for bonding is disposed

9, the force-touch type display device according to the present embodiment includes a display panel 710 including a first electrode 712 for touch sensing, and a display panel 710 covering the rear surface of the edge area of the display panel A cutter cover bottom 730 which is a cut first support part to be disposed, a mid frame 750 which is disposed at the rear of the cut cover bottom to cover the entire rear surface of the display panel, And a gap retaining adhesive member 770 disposed between the cut cover bottom 730 and the mid frame 750. The gap between the cut cover bottom 730 and the mid frame 750 can be adjusted by the adhesive force.

The touch driver 780 may be included in a data driver circuit (D-IC) for controlling the video output of the display panel, and therefore, the touch driver may be represented by a data driver circuit for the sake of convenience, but the present invention is not limited thereto.

Meanwhile, the touch driver 780 according to the present embodiment performs a force touch operation for recognizing the touch pressure of a user applied to the display panel as a force touch, and the force touch operation is performed by applying a first electrode driving signal to the first electrode And applies a second electrode driving signal GND to the mid frame 750 functioning as a second electrode to sense the touch pressure of the user applied to the display panel.

On the other hand, as shown in the enlarged view of FIG. 9, the gap maintaining adhesive member 770 has a first adhesive surface 772 adhered to the lower outer surface of the cut cover bottom, and a second adhesive surface 772 adhered to the inner surface of the mid frame 750 And a base film layer 776 having elasticity, which is further disposed between the two adhesive surfaces.

Further, the gap maintaining bonding member 770 is preferably formed of a nonconductive material.

Since the second capacitance between the first electrode and the second electrode is measured after the ground signal (second electrode driving signal) is applied to the mid frame 750, which is the second electrode, when the force touch is sensed, The frame and the cut bottom cover should be electrically isolated.

This is because when the midframe and the cover bottom are electrically connected, the ground signal GND applied to the midframe is transmitted to the cover bottom so that the ground signal is also applied to the cover bottom. In such a case, ) Is not measured.

Therefore, the gap maintaining bonding member 770 is made of a nonconductive material, thereby electrically insulating the midframe, which is the second electrode, from the cut cover bottom, and the force touch performance can be maintained.

The gap maintaining adhesive member 770 may be composed of a release adhesive film made of a transparent material such as PET or a double-sided tape or the like, but it is not limited thereto, and may be bonded to the cover bottom and the midframe, And may be constituted by other members as long as the gap G between both members can be kept constant.

The gap maintaining adhesive member 770 maintains a constant gap between the cut cover bottom and the midframe to prevent weakening of the force touch performance due to impact / vibration, Auto Baseline Tracking) can be smoothly performed.

The gap maintaining adhesive member 770 also has an effect of preventing foreign matter from flowing into the display area of the display device.

As described later, in order to perform the auto baseline tracking, the amount of change in gap between the cover bottom and the midframe due to impact / vibration must be maintained at 0.5 mm or less. Therefore, the gap maintaining adhesive member 770 The thickness may be 0.5 mm or less.

On the other hand, in the structure shown in FIG. 7, since the midframe 730 is always used as the second electrode, in order to solve the problem that the force touch can not be performed in the edge region partially overlapping the cut cover bottom, The touch driver 780 may further include a function of selecting one of the cover bottom 730 and the mid frame 750 as the second electrode in the force touch operation and applying the ground signal.

That is, according to the present embodiment, the cover bottom 730 cut as shown in FIG. 7 is used as the first support portion of the display module, and the mid frame 750 at the rear side is used as the support structure of the entire display device The second electrode is selected as one of the cover bottom and the midframe cut along the touch sensing area at the time of the force touch. That is, according to the present embodiment, a cut cover bottom 730 cut in addition to the mid frame 750 can also be used as the second electrode for the force touch.

In this case, the second electrode driving signal may be a ground signal, and the touch driving unit may apply a second electrode driving signal, which is a ground signal, to the selected second electrode, measure a change in capacitance between the first electrode and the second electrode, Can be determined.

More specifically, when the touch driver 780 senses the touch pressure in the center area A1 of the first electrode where the cut cover bottom 730 is not overlapped, the touch driver 780 selects the mid frame 750 as the second electrode And selects the cut cover bottom 730 as the second electrode when sensing the touch pressure of the edge region A2 of the partially overlapping first electrode with the cut cover bottom.

At this time, the touch driver can drive the touch input sensing in the center area A1 and the touch input sensing in the edge area A2 in a time division manner.

9, the touch driver 780 according to the present embodiment includes a cut cover bottom 730 for force touch sensing in an edge area A2 partially overlapped with the cut cover bottom in the first electrode area, (First electrode driving signal) applied to the first electrode 712 and the first electrode 712 applied to the first electrode driving signal by measuring a change in the first capacitance C1 formed between the second electrode and the second electrode, Lt; / RTI >

In addition, the touch driver 780 applies a ground signal (the second signal) to the mid frame 750, which is the rear support structure of the set device, for the force touch detection in the central region A1 that does not overlap with the cut cover bottom in the first electrode region, Touch sensing is performed by measuring a change in the second capacitance C2 formed between the first electrode 712 to which the first electrode driving signal is applied and the second electrode after the electrode driving signal is applied.

Thus, unlike the case described with reference to FIG. 7, there is an effect that the force touch can be detected even in the edge area A2 where the cutting cover bottom touches the display area. Therefore, the case where the cut cover bottom is overlapped only with a part of one line of touch electrodes (that is, the outermost touch electrode block) disposed at the edge, and the case where one line of touch electrodes The force touch performance in the outermost touch electrode block can be improved in both cases where the touch electrode block is overlapped with the entire outermost touch electrode block.

On the other hand, a portion not selected as the second electrode among the cut cover bottom and midframe should always be floated and maintained in a high impedance state (Hi-Z).

According to the present embodiment, a backlight unit 720 may be further disposed between the display panel 710 and the cut cover bottom 730 to supply light to the display panel.

In particular, a first air gap AG1 must be formed between the backlight unit 720 and the display panel 710 for force touch sensing in the edge area A2.

9, an adhesive member 714 or the like having a predetermined thickness may be disposed between the edge of the display panel 710 and the cutting cover bottom 730 so that both the backlight unit and the display The first air gap AG1 can be formed between the first air gap AG1 and the second air gap AG2.

Accordingly, when touch operation is performed in the edge area A2, the interval of the first air gap changes, and the touch input position can be determined by sensing the change of the first capacitance C1.

On the other hand, in the central region A1 where the cover bottom is removed, a second air gap AG2 is formed between the backlight unit 720 and the mid frame 750 in addition to the above-described first air gap.

Therefore, when the force touch is sensed in the central area A1, the first air gap AG1 and the second air gap AG2 are all changed in size according to the touch pressure of the user, and the change amount of the second capacitance C2 The position of the force touch can be determined.

At this time, the changeable gap between the positive electrodes in the central region A1 becomes the sum of the first air gap and the second air gap, and the changeable gap between the positive electrodes in the edge region A2 becomes the first air gap.

Meanwhile, the touch driving unit 780 can drive the force touch input sensing in the central area A1 and the touch input sensing in the edge area A2 in a time-division manner, thereby smoothly performing the force touch operation in the entire display panel have.

The cut cover bottom 730 is not limited to the term, but may be a plate bottom, a base frame, a metal frame, a metal chassis, a chassis base Chassis base, m-chassis, etc., and includes any type of frame or plate structure that supports the rear edge of at least one of the display panel and the backlight unit.

However, unlike a general cover bottom, the cut cover bottom 730 used in the present embodiment is not disposed in the central area of the display device, but supports only the edge of the display device.

It should also be understood that the midframe 750 in this specification is not limited to that term and includes all types of support structures that support the rearmost of the set-up device as an end product including a display panel, (Back Cover), Set Cover, and the like.

In the case of a liquid crystal display panel, the display panel 710 used in the present embodiment includes a plurality of gate lines, data lines, pixels defined in the intersecting regions thereof, An array substrate including a thin film transistor as a switching element, an upper substrate provided with a color filter and / or a black matrix, and a liquid crystal material layer formed therebetween.

Of course, the present embodiment is not limited to the liquid crystal display device, and may include a first electrode for sensing the touch and a second electrode for sensing the force touch according to the gap change It can be applied to all types of display methods.

The first electrode 712 according to the present embodiment also functions as a common electrode for supplying common electrodes to pixels included in the display panel, and one first electrode can be arranged to cover a plurality of pixels.

10 shows an example of the arrangement of the first electrodes of the force-touch type display device according to the present embodiment, in which two touch electrode groups are symmetrically arranged, and each of the touch electrode groups has k (k = 9 ) Number of touch electrode blocks.

10, a first electrode, which is a touch electrode included in a display panel, includes a plurality of touch electrode block groups disposed on a display panel, and each touch electrode block group includes a plurality of touch electrode blocks Lt; / RTI >

10, the first electrode includes a first touch electrode block group including k first touch electrode blocks arranged on the left side (first side) of the display panel, and a second touch electrode block group including k first touch electrode block groups on the right side The first touch electrode block and the second touch electrode block including the k second touch electrode blocks arranged symmetrically on the first touch electrode block and the second touch electrode block, ≪ / RTI >

That is, the first touch electrode block group on the left side of the display panel is composed of the first touch electrode block to the ninth first touch electrode block, and the second touch electrode block group on the right side of the display panel is also the first second touch electrode block to 9 Th second touch electrode block.

9, a total of nine first touch electrode blocks are disposed on the left side of the display panel and nine second touch electrode blocks are disposed symmetrically on the right side of the display panel, It consists of 32 touch electrodes in total.

As a result, a total of 18 * 32 first electrodes (touch electrodes) are disposed on the display panel. It is needless to say that each of the touch electrode and the touch electrode block does not have to be the same size and number, and for example, the touch electrode block disposed at the edge of the display panel is composed of a smaller number of blocks or touch electrodes than the remaining touch electrodes, .

In addition, a touch multiplexer (T-MUX) 1190, 1190 'for switching application of a touch driving signal to a plurality of touch electrodes included in the first touch electrode block and the second touch electrode block, The multiplexer T-MUX is composed of a first T-MUX 1190 for the first touch electrode block on the left side and a second T-MUX 1190 'for the second touch electrode block on the right side .

As described below, the first T-MUX 1190 sequentially applies first electrode driving signals to nine first touch electrode blocks to perform touch sensing, and the second T-MUX 1190 ' The first electrode driving signal is sequentially supplied to nine second touch electrode blocks to perform touch sensing.

Meanwhile, operations of the first T-MUX 13190 and the second T-MUX 1190 'may also be performed symmetrically.

That is, when the first T-MUX applies the first electrode driving signal to the i-th first touch electrode block, the second T-MUX also applies the first electrode driving signal to the i-th second touch electrode block.

11 shows a flow of the force touch performance checking method of the touch display apparatus according to the present embodiment.

9, a force calibration process and an inspection process can be performed to equalize the force touch performance.

11 is an overall flowchart of a method for checking the performance of such a display device, which can be performed as follows.

First, after the assembly of the display device (S1110), the force touch calibration process (S1120) is performed.

This force touch calibration process S1120 is a process of calculating a force touch measurement value by pressing a block of the first electrode included in the display device at a constant pressure using a robot or the like and then normalizing the measured value .

That is, under the same conditions as the general force-touch sensing (applying the first electrode driving signal to the first electrode and ground signal to the mid-frame, which is the second electrode), the same pressure is applied to each touch electrode block constituting the first electrode , And measures a second capacitance caused between both electrodes.

The force touch calibration step S1120 is divided into detailed steps. First, each of the plurality of first touch electrode blocks constituting the first electrode is pressed at a constant pressure, and then the capacitance value is measured for each first touch electrode block And standardizing the measured capacitance value of the first touch electrode block.

In the ideal case, the second capacitance value measured for all the touch electrode blocks, that is, the force touch measurement value, may have the same or a distribution characteristic such as a normal distribution. However, due to the assembly tolerance, The measured force touch values may be different from each other or deviate from the normal distribution characteristic.

Therefore, normalization is performed to correct the force touch measurement value to be uniform in all areas.

That is, a normalization process is performed, which is a process of smoothing the force-touch measurement value or compensating for each touch electrode block by a weight or an add-subtract value so as to have a normal distribution characteristic.

In this case, the data to be added to or subtracted from the force touch measurement value may be represented by the compensation data or the force touch calibration data, and the force touch calibration data may have a different value for each touch electrode block of the first electrode.

Next, the first force touch inspection process is performed (S1130)

The first force touch inspection process (S1130) performs force touch evaluation on all the display devices or all the touch electrode blocks, and then measures an error with respect to a predetermined specification.

Next, after the shock / vibration test (S1140) is performed on the display device, a second force touch inspection is performed (S1150)

In the Second Force Touch Inspection, force touch re-evaluation is performed on all the display devices or all the touch electrode blocks in the same manner as the first force touch inspection process after exposure to vibration / test conditions, (Specification) is measured again,

According to the performance testing method of the display device as shown in FIG. 11, when the gap between the cover bottom and the mid frame greatly changes after the vibration / impact test, the force touch measurement value by the secondary force touch test can be greatly changed .

In this case, even if the force touch calibration is performed again, the error caused by the gap change can not be solved, or the force touch calibration may not be performed again.

As a result of the test, if the variation of the gap between the cover bottom and the mid frame according to the vibration / impact test is 0.5 mm or more, the force touch calibration can not be performed again or the error can not be sufficiently corrected after the force touch calibration is performed again .

Therefore, in the present embodiment, as shown in Fig. 9, a gap holding adhesive member is disposed between the cut cover bottom and the midframe to prevent such defects.

FIG. 12 shows an overall flow of a touch performance maintenance method according to the present embodiment including an automatic baseline tracking process for correcting force touch calibration data (Force Calibration Data) after a vibration / impact test.

The touch performance maintaining method according to the present embodiment is similar to the process shown in FIG. 11, but includes an automatic baseline tracking step of correcting force touch calibration data (Force Calibration Data) (S1250) is further added.

In detail, in the touch performance maintaining method according to the present embodiment, first, the force touch calibration process (S1220) is performed after the assembly of the display device (S1210).

Next, a first force touch inspection process is performed (S1230), an impact / vibration test (S1240) is performed on a display device, and then an automatic baseline tracking (S1250) Is performed.

Subsequent to the auto baseline tracking step S1250, a second force touch inspection is performed (S1260)

Among these steps, the force touch calibration process (S1220) and the configurations of the first and second force touch tests are the same as those described with reference to FIG. 11, so that detailed description is omitted in order to avoid redundancy.

On the other hand, the auto baseline tracking step S1250 is a non-touch force touch performance maintaining function for correcting the force calibration data after the vibration / impact test.

FIG. 13 shows a detailed flow of an automatic baseline tracking process for correcting force calibration data after a vibration / impact test.

9, the display device in which automatic baseline tracking according to the present embodiment is performed includes a display panel 710 including a first electrode 712 for touch detection, (750, second support portion) disposed at the rear of the cut cover bottom (730) to cover the entire rear surface of the display panel, and a second cover A touch driver 780 for applying a first electrode driving signal to one electrode and applying a second electrode driving signal to a midframe serving as a second electrode to sense a touch pressure of a user applied to the display panel, And a gap holding bonding member 770 disposed between the cover bottom and the midframe.

Particularly, in order for the automatic baseline tracking according to the present embodiment to be smoothly performed, the amount of change in the clearance between the cover bottom and the midframe must be 0.5 mm or less by the vibration / impact test. And a gap holding adhesive member 770 disposed between the gap holding member 770.

As shown in FIG. 13, the automatic baseline tracking according to this embodiment is performed in the following process.

First, a touch driving signal for autobase line tracking is applied to the second electrode (S1310)

At this time, the touch driving signal is a load free driving signal (LFDS), which may be the same signal as the first electrode driving signal applied to the first electrode of the display panel during a general force touch driving period, no.

The touch driving signal may be a signal that is the same as the common voltage (Vcom) signal applied to the first electrode in the display mode, the load free driving signal (LFDS).

However, since the touch driving signal for auto-base line tracking is applied only to the mid-frame, which is the second electrode, to induce the induction signal to the first electrode which is the opposite electrode, Lt; / RTI > signal.

Next, the induced signal induced in the first electrode is measured by the rod-free driving signal applied to the second electrode (S1320)

In this case, the inductive signal induced at the first electrode may be an inductive capacitance value measured at the first electrode, but is not limited thereto, and may be a load-free driving signal (a touch electrode driving signal for autobase line tracking) applied to the second electrode, Lt; RTI ID = 0.0 > 1 < / RTI >

Next, the induced signal measured at the first electrode is compared with a previously stored standard value (S1330), and the force touch calibration data for the first electrode is compensated according to the comparison result (S1340). That is, The force touch calibration data generated in the above-described force touch calibration step is corrected.

In this case, the standard value refers to a value obtained by previously measuring and storing the induction signal derived from the first electrode through the same process as S1310 and S1320 above according to the amount of change in gap between the cut cover bottom and the midframe.

For example, if the induced signal value at the first electrode and the induced signal value at the first electrode when the gap change amount is 0.1 mm are measured in the state where there is no gap change after assembly of the display device, .

These standard values may be implemented as a look-up table prepared for each display device before the vibration / impact test.

10, when the first electrode is composed of a plurality of touch electrode blocks, the above-mentioned induction signal measurement and port touch calibration data compensation are performed for each touch electrode block, so that more accurate compensation is possible.

That is, even when the standard value is prepared, the calibration signal value based on the difference value from the standard value can be prepared for each of the touch electrode blocks.

The lookup table of this standard value may have the following format, but is not limited thereto.

As shown in the table, the standard value look-up table is divided into a reference value which is an induced signal value (capacitance value) derived from the first electrode and a reference value which is necessary for the force touch calibration And may include a compensation value.

Also, the reference value, which is the induction signal value (capacitance value) derived from the first electrode, and the force touch calibration compensation value required at that time, are set for each touch electrode block of the first electrode (nine first touch electrodes Block and nine touch electrode blocks on the right side).

Therefore, after the vibration / test, the induction signal value at the first electrode is measured in step S1320, and then the force value is compared with reference values (standard values) of the standard value lookup table described above. Then, the corresponding force touch calibration compensation value is extracted, Data is compensated.

The autobase line tracking used in this specification is only one example, and it is also possible to apply the force-free driving signal (touch driving signal) to the second electrode, and then the force touch calibration data And < RTI ID = 0.0 > a < / RTI >

On the other hand, as described above, when the amount of change in the clearance between the cover bottom and the midframe is 0.5 mm or more, the above-described auto baseline tracking function and force touch calibration compensation through it are not possible at all.

Therefore, in this embodiment, the gap change holding member 770 is disposed between the cut cover bottom and the mid frame to minimize the gap change amount? G.

By using such an auto-baseline tracking method, the accuracy of the force touch calibration can be improved, and as a result, the force touch performance can be improved.

Further, by arranging the gap maintaining bonding member 770 between the cut cover bottom and the midframe, the gap variation amount? G can be minimized to perform the auto baseline tracking function and force touch calibration compensation as described above, Thereby improving the force touch accuracy.

As described above, in the touch-type display device according to the present embodiment, in the force-touch method in which a part of the cover bottom, which is the rear support structure of the display panel, is cut, It is possible to secure a touch performance.

More specifically, by arranging a gap holding adhesive member between the outer surface of the cover bottom of the display module and the inner surface of the mid frame of the setting device, it is possible to uniformly maintain the air gap which is the gap between the both electrodes, There is an effect that can be secured.

In addition, since the force calibration data is corrected after the shock / vibration test of the touch display device using the auto-base line tracking function, the same force touch performance can be maintained before and after the vibration / impact test.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the inventions. , Separation, substitution, and alteration of the invention will be apparent to those skilled in the art. Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention should be construed according to the following claims, and all technical ideas within the scope of equivalents should be construed as falling within the scope of the present invention.

710: display panel 712: first electrode (touch electrode)
720: Backlight unit 730: Covered bottom cover (Cover Bottom)
740: Cover Glass 750: Mid Frame
770: gap holding adhesive member 780: touch driving part (D-IC)

Claims (10)

A display panel including a first electrode for touch sensing;
A cut first support portion disposed to cover a rear surface of an edge region of the display panel;
A second support portion disposed behind the cut first support portion and covering the entire rear surface of the display panel;
A touch driver which applies a first electrode driving signal to the first electrode, selects the second supporting portion as a second electrode, and senses a touch pressure of a user applied to the display panel by applying the second electrode driving signal, ;
A gap holding adhesive member disposed between the first support portion and the second support portion;
And a display device. The method according to claim 1,
Wherein the gap maintaining adhesive member is made of a nonconductive material including a first adhesive surface bonded to the outer surface of the first support portion and a second adhesive surface adhered to the inner surface of the second support portion. 3. The method of claim 2,
Wherein the gap maintaining adhesive member has a thickness of 0.5 mm or less. The method according to claim 1,
When the touch pressure is sensed in the central region of the first electrode where the cut cover bottom is not overlapped, the touch support portion may be positioned at the center of the cut- And selects the cut cover bottom as the second electrode when the mid-frame is selected as the second electrode and the touch pressure of the edge region of the first electrode partially overlapped with the cut cover bottom is sensed. A display device comprising: a display panel including a first electrode for touch detection; a cut first support portion disposed to cover a rear surface of an edge region of the display panel; and a second support portion disposed behind the cut first support portion, A touch driver for sensing a touch pressure of a user applied to the display panel and a gap holding adhesive member disposed between the first and second supports, As a touch performance maintaining method,
Applying a touch driving signal to the second electrode;
Measuring an inductive signal induced at the first electrode by a touch driving signal applied to the second electrode;
Comparing the measured induction signal with a plurality of pre-stored standard values, and compensating for force touch calibration data according to the comparison result;
Wherein the touch display device is a touch display device. 6. The method of claim 5,
Before applying the touch driving signal,
Measuring a capacitance value for each touch electrode block after pressing a plurality of touch electrode blocks constituting the first electrode at a constant pressure;
Standardizing the measured capacitance value of each touch electrode block;
And performing a force-touch calibration process including the touch-touch calibration process. 6. The method of claim 5,
In the step of measuring the inductive signal, an induced signal induced in each of the touch electrode blocks constituting the first electrode is measured,
Wherein the compensation of the force touch calibration data compensates the force touch calibration data for each of the touch electrode blocks according to the comparison result. 6. The method of claim 5,
Wherein the standard value is a lookup table provided for each display device before the vibration / impact test, and includes a reference value of the induction signal according to a change amount of a gap between the first support part and the second support part. 6. The method of claim 5,
Wherein the gap maintaining adhesive member comprises a non-conductive material including a first adhesive surface bonded to the outer surface of the first support portion and a second adhesive surface bonded to the inner surface of the second support portion, Maintenance method. 10. The method of claim 9,
Wherein the gap maintaining adhesive member has a thickness of 0.5 mm or less.

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