KR20070044122A - Liquid crystal display - Google Patents

Abstract

The present invention relates to a liquid crystal display device, wherein the liquid crystal display device includes a common electrode display panel having a first common electrode, a thin film transistor array panel facing the common electrode display panel, and having a pixel electrode, the common electrode display panel, and the thin film. A liquid crystal layer formed between the transistor display panel, and a liquid crystal capacitor having the common electrode and the pixel electrode as two terminals, wherein the thin film transistor display panel includes a plurality of image scanning lines, a plurality of image data lines crossing the image scanning line, A plurality of sensing data lines parallel to the image scanning line or the image data line, the plurality of first switching elements connected to the image scanning line, the image data line and the pixel electrode, and the second common and the sensing data lines. It comprises a plurality of second switching elements connected.

Display, Sensor, Pixel, Liquid Crystal Display, Touch Screen, Sensor, LCD

Description

Liquid crystal display {LIQUID CRYSTAL DISPLAY}

1 is a block diagram of a liquid crystal display according to an exemplary embodiment of the present invention, which is a block diagram of the liquid crystal display shown in terms of a pixel.

2 is an equivalent circuit diagram of one pixel of a liquid crystal display according to an exemplary embodiment of the present invention.

3 is a block diagram of a liquid crystal display according to an exemplary embodiment of the present invention, and is a block diagram of the liquid crystal display shown in terms of a sensing unit.

4 is an equivalent circuit diagram of a sensing unit of a liquid crystal display according to an exemplary embodiment of the present invention.

5 is a diagram illustrating a connection relationship between a part of the sensing unit illustrated in FIG. 4 and a pixel electrode.

The present invention relates to a liquid crystal display device.

Typical liquid crystal displays (LCDs) among display devices include two display panels provided with pixel electrodes and a common electrode, and a liquid crystal layer having dielectric anisotropy interposed therebetween. The pixel electrodes are arranged in a matrix and connected to switching elements such as thin film transistors (TFTs) to receive data voltages one by one in sequence. The common electrode is formed over the entire surface of the display panel and receives a common voltage. The pixel electrode, the common electrode, and the liquid crystal layer therebetween form a liquid crystal capacitor, and the liquid crystal capacitor becomes a basic unit that forms a pixel together with a switching element connected thereto.

In such a liquid crystal display, a voltage is applied to two electrodes to generate an electric field in the liquid crystal layer, and the intensity of the electric field is adjusted to adjust the transmittance of light passing through the liquid crystal layer to obtain a desired image.

A touch screen panel is a device that touches a finger or a touch pen (stylus) on the screen to write and draw letters or pictures, or execute icons to perform a desired command on a machine such as a computer. . A liquid crystal display with a touch screen panel may find out whether a user's finger or a touch pen touches the screen and contact position information. However, such a liquid crystal display device has problems such as a cost increase due to a touch screen panel, a decrease in yield due to a process of adhering the touch screen panel to a liquid crystal display panel, a decrease in luminance of the liquid crystal panel, and an increase in product thickness.

Therefore, in order to solve these problems, a technology for embedding a sensing element in a liquid crystal display device instead of a touch screen panel has been developed. The sensing element detects a change in light or pressure applied to the screen by the user's finger or the like so that the liquid crystal display may determine whether the user's finger or the like touches the screen and the contact position information.

However, when such a sensing element is embedded in a liquid crystal display device, a space for designing the reducing element must be secured after securing a separate space for the sensing element, thereby reducing design margin. In addition, in the case of a display device requiring a high resolution, the built-in sensing element adversely affects the resolution, thereby making it impossible to apply the sensing element.

Accordingly, an object of the present invention is to provide a liquid crystal display device which does not reduce the design margin or resolution even when a sensing element is incorporated.

According to an aspect of the present invention, a liquid crystal display device includes: a first display panel having a first electrode, a second display panel facing the first display panel, and having a second electrode; And a liquid crystal layer formed between the display panel and the second display panel, and a liquid crystal capacitor having the first electrode and the second electrode as two terminals, wherein the second display panel crosses a plurality of image scanning lines and the image scanning line. A plurality of image data lines, a plurality of sensing data lines parallel to the image scanning line or the image data line, a plurality of first switching elements connected to the image scanning line, the image data line and the second electrode, and the second And a plurality of second switching elements connected to an electrode and the sensing data line.

The liquid crystal display according to the above characteristic further includes a plurality of voltage applying lines connected to each of the plurality of second switching elements to apply a driving voltage.

Preferably, the first electrode receives a predetermined voltage to reciprocate two values. In this case, the predetermined voltage may be a common voltage.

It is preferable that the capacitance of the liquid crystal capacitor is changed by pressure.

Preferably, the distance between the first electrode and the second electrode is changed by the pressure and accordingly the capacitance of the liquid crystal capacitor is changed.

The liquid crystal display according to the feature further includes a plurality of variable capacitors connected to the second electrode and the first switching element. In this case, the variable capacitor preferably maintains a constant capacitance.

The variable capacitor may be a parasitic accumulator generated by the overlap of the second electrode and the image main line.

DETAILED DESCRIPTION Embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention.

In the drawings, the thickness of layers, films, panels, regions, etc., are exaggerated for clarity. Like parts are designated by like reference numerals throughout the specification. When a part of a layer, film, region, plate, etc. is said to be "on" another part, this includes not only the other part being "right over" but also another part in the middle. On the contrary, when a part is "just above" another part, there is no other part in the middle.

A liquid crystal display, which is an example of a display device according to an exemplary embodiment, will now be described in detail with reference to FIGS. 1 to 5.

1 is a block diagram of a liquid crystal display according to an exemplary embodiment of the present invention, which is a block diagram of a liquid crystal display according to a pixel, and FIG. 2 is a pixel of the liquid crystal display according to the exemplary embodiment of the present invention. Equivalent circuit diagram. 3 is a block diagram of a liquid crystal display according to an exemplary embodiment of the present invention, which is a block diagram of the liquid crystal display according to a sensing unit, and FIG. 4 is a sensing diagram of the liquid crystal display according to the exemplary embodiment of the present invention. Equivalent circuit diagram for negative. 5 is a diagram illustrating a connection relationship between a part of the sensing unit illustrated in FIG. 4 and a pixel electrode.

1 and 3, a liquid crystal display according to an exemplary embodiment of the present invention may include a liquid crystal panel assembly 300, an image scanning unit 400, an image data driver 500, and a liquid crystal panel assembly 300 connected thereto. A sensing signal processor 800, a gray voltage generator 550 connected to the image data driver 500, a contact determiner 700 connected to the sensing signal processor 800, and a signal controller 600 for controlling them. .

1 to 5, the liquid crystal panel assembly 300 includes a plurality of display signal lines G1 -Gn and D1-Dm, a plurality of pixels PX connected to the plurality of display signal lines G1-Gn, D1-Dm, and arranged in a substantially matrix form. Connect to sensing signal lines (SX1-SXα, SY1-SYβ, VL1-VLγ) (where α, β and γ are natural numbers), a plurality of sensing signal lines (SX1-SXα, SY1-SYβ, VL1-VLγ) and pixels (PX) And a plurality of amplifiers AMP arranged in a substantially matrix form.

Referring to FIG. 2, the liquid crystal panel assembly 300 includes a thin film transistor array panel 100 and a common electrode panel 200 facing each other and a liquid crystal layer 3 interposed therebetween.

The display signal lines G1 -Gn and D1 -Dm include a plurality of image scanning lines G1 -Gn for transmitting an image scanning signal and image data lines D1 -Dm for transmitting an image data signal.

The sensing signal lines SX1-SXα, SY1-SYβ, VL1-VLγ are a plurality of horizontal sensing data lines SY1-SYβ and a plurality of vertical sensing data lines SX1-SXα and an amplifier AMP which transmit sensing data signals. And a voltage application line (VL1-VLγ) for applying a drive voltage Vdd from the outside.

The image scanning lines G1 -Gn and the horizontal sensing data lines SY1 -SYβ extend substantially in the row direction and are substantially parallel to each other, and the image data lines D1 -Dm, the sensing data lines SX1 -SXα, and voltage are applied. Lines VL1-VLγ extend approximately in the column direction and are substantially parallel to each other.

Each pixel PX includes a switching element Q connected to the display signal lines G1 -Gn and D1 -Dm, a liquid crystal capacitor Clc, and a storage capacitor Cst connected thereto. . Holding capacitor Cst can be omitted as needed.

The switching element Q is a three-terminal element such as a thin film transistor provided in the thin film transistor array panel 100, the control terminal of which is connected to the image scanning line G1-Gn, and the input terminal of the image data line D1-. Dm), and the output terminal is connected to the liquid crystal capacitor Clc and the storage capacitor Cst. In this case, the thin film transistor includes amorphous silicon or poly crystalline silicon.

The liquid crystal capacitor Clc has two terminals, the pixel electrode 191 of the thin film transistor array panel 100 and the common electrode 270 of the common electrode display panel 200, and the liquid crystal layer 3 between the two electrodes 191 and 270. Functions as a dielectric. The pixel electrode 191 is connected to the switching element Q, and the common electrode 270 is formed on the entire surface of the common electrode display panel 200 and receives the common voltage Vcom. Unlike in FIG. 2, the common electrode 270 may be provided in the thin film transistor array panel 100. In this case, at least one of the two electrodes 191 and 270 may be linear or rod-shaped.

The storage capacitor Cst, which serves as an auxiliary role of the liquid crystal capacitor Clc, is formed by overlapping a separate signal line (not shown) and the pixel electrode 191 provided in the thin film transistor array panel 100 with an insulator interposed therebetween. A predetermined voltage such as the common voltage Vcom is applied to this separate signal line. However, the storage capacitor Cst may be formed such that the pixel electrode 191 overlaps the front end image scanning line directly above the insulator.

On the other hand, in order to implement color display, each pixel PX uniquely displays one of the primary colors (spatial division) or each pixel PX alternately displays the primary colors over time (time division). The desired color is recognized by the spatial and temporal sum of these primary colors. Examples of the primary colors include three primary colors such as red, green, and blue. FIG. 2 illustrates that each pixel PX includes a color filter 230 representing one of the primary colors in an area of the common electrode display panel 200 corresponding to the pixel electrode 191 as an example of spatial division. . Unlike FIG. 2, the color filter 230 may be formed above or below the pixel electrode 191 of the thin film transistor array panel 100.

At least one polarizer (not shown) for polarizing light is attached to an outer surface of the liquid crystal panel assembly 300.

Each amplifier AMP has a control terminal connected to the pixel PX, an input terminal connected to a voltage applying line VL1-VLγ, and an output terminal connected to the corresponding sensing data lines SX1-SXα and SY1-SYβ. A switching element SQ such as a thin film transistor connected (hereinafter, referred to as a "sensing part switching element"). This amplifier AMP functions as a current-voltage amplifier that outputs a voltage of that magnitude in accordance with the magnitude of the current of the signal applied to the control terminal. This thin film transistor includes amorphous silicon or poly crystalline silicon.

Some elements of the pixel PX having such a structure and the amplifier AMP connected to the pixel PX function as a sensing unit SU for determining whether or not a finger or the like is in contact.

Next, the structure of the sensing unit SU will be described in more detail with reference to FIGS. 4 and 5.

In FIG. 4, a horizontal or vertical sensing data line (hereinafter, referred to as a sensing data line) indicated by a reference numeral SL, and VL _k is a k-th voltage applying line.

As shown in FIG. 4, the sensing unit SU includes a capacitor CS and an amplifier AMP.

The capacitor CS of the sensing unit SU includes a liquid crystal capacitor Clc and a reference capacitor Cp of the pixel PX.

As described above, the liquid crystal capacitor Clc is connected to the pixel electrode 191 and the common electrode 230. The reference capacitor Cp uses various parasitic capacitors generated between the switching element Q of the pixel PX and the pixel electrode 191. As shown in FIG. 5, when the pixel electrode 191 overlaps with the corresponding gate line G _{i in} order to improve the aperture ratio and the like, the generated parasitic capacitor may be used as the reference capacitor Cp. The parasitic capacitor used as the reference capacitor Cp preferably maintains a constant capacitance regardless of external influences.

In the sensing unit switching element SQ, which is an amplifier AMP, a control terminal is connected to the pixel electrode 191, which is one terminal of the liquid crystal capacitor Clc, and as described above, an input terminal is connected to the voltage applying line VL _k . The output terminal is connected to the sensing data line SL.

The horizontal sensing data line SL may be formed on the same layer with the same material as the image scanning lines G1-Gn, and the vertical sensing data line SL and the voltage applying line VL _k are the image data lines D1-Dm. It may be formed in the same layer of the same material as).

In addition, in order to connect the control terminal of the sensing unit switching element SQ and the pixel electrode 191, there is no need to form a separate connecting member, and to connect the control terminal of the switching element Q and the liquid crystal capacitor Clc. The formed contact portion (not shown) is used.

The sensing unit SU is disposed between two adjacent pixels PX. The density of the pair of sensing units SU, which are connected to the horizontal and vertical sensing data lines SY1 -SYβ and SX1-SXα, and disposed in the area where they cross, is preferably lower than the dot density. For example, it may be about 1/4 of the dot density. Therefore, one sensing unit SU connected to the horizontal sensing data lines SY1 -SYβ may be formed every four dots, and one sensing unit SU connected to the vertical sensing data lines SX1-SXα may also be formed every four dots. have.

 Here, one dot includes, for example, three pixels PX arranged side by side and displaying three primary colors such as red, green, and blue, displaying one color, and a basic unit representing the resolution of the liquid crystal display device. do. However, one dot may consist of four or more pixels PX. In this case, each pixel PX may display one of three primary colors and white.

An example in which the density of the pair of sensing units SU is 1/4 of the dot density is one in which the horizontal and vertical resolutions of the pair of sensing units SU are 1/2 of the horizontal and vertical resolutions of the liquid crystal display device, respectively. Can be. In this case, there may be a pixel row and a pixel column without the sensing unit SU.

On the other hand, the image data lines D1-Dm are arranged in opposite directions (left or right with respect to the pixel) with respect to the sensing unit SU, and the image data lines D1 -Dm between adjacent dots are also mutually opposite. It is placed in the opposite position. Due to the arrangement of the image data lines D1 to Dm, virtual switching elements having the same shape as the sensing unit switching element SQ are formed at portions where no image data lines D1 to Dm are formed between adjacent dots. Not shown). The virtual switching element is not connected anywhere.

As a result, the distance between the image data lines D1 -Dm and the sensing data lines SX1 -SXα and SY1 -SYβ increases, so that the distortion of the sensing data signal due to the change of the image data signal is reduced. In addition, the gap between the adjacent dots of the corresponding portion is increased by the formation of the sensing unit SU, thereby compensating for the occurrence of the gap between the adjacent dots of the portion where the sensing unit SU is not formed, thereby detecting the sensing unit SU. ) To prevent the deterioration of image quality caused by the gap between the dots due to the formation of the ").

This arrangement structure can be similarly applied to the case where the dot is formed of four or more pixels PX.

Referring back to FIGS. 1 and 3, the gray voltage generator 550 generates two sets of gray voltage sets (or reference gray voltage sets) related to the transmittance of the pixel. One of the two sets has a positive value for the common voltage Vcom and the other set has a negative value.

The image scanning unit 400 is connected to the image scanning lines G1 -Gn of the liquid crystal panel assembly 300 to control the gate-on voltage Von for turning on the switching element Q and the gate-off voltage Voff for turning off. The combined image scan signal is applied to the image scan lines G1 -Gn.

The image data driver 500 is connected to the image data lines D1 -Dm of the liquid crystal panel assembly 300 and selects a gray voltage from the gray voltage generator 550 and uses the image data line as an image data signal. D1-Dm). However, when the gray voltage generator 550 provides only a predetermined number of reference gray voltages instead of providing all of the voltages for all grays, the image data driver 500 divides the reference gray voltages into the total grays. A gray voltage is generated and an image data signal is selected from among them.

The sensing signal processor 800 is connected to the data lines SX1-SXα and SY1-SYβ of the liquid crystal panel assembly 300 to receive the sensing data signals output through the sensing data lines SX1-SXα and SY1-SYβ. After signal processing such as amplification and filtering, analog-to-digital conversion is performed to generate a digital sense signal DSN.

The touch determining unit 700 receives the digital sensing signal DSN from the sensing signal processing unit 800, performs a predetermined calculation process, determines whether the contact is made, and the contact position, and then sends the contact information INF to the external device. The touch determination unit 700 may monitor an operation state of the sensing unit SU based on the digital sensing signal DSN and control signals applied to the sensing unit SU.

The signal controller 600 controls operations of the image scanning unit 400, the image data driver 500, the gray voltage generator 550, and the detection signal processor 800.

Each of the driving devices 400, 500, 550, 600, 700, and 800 may be mounted directly on the liquid crystal panel assembly 300 in the form of at least one integrated circuit chip, or may be a flexible printed circuit film ( It may be mounted on the liquid crystal panel assembly 300 in the form of a tape carrier package (TCP) or mounted on a separate printed circuit board (not shown). In contrast, these driving devices 400, 500, 550, 600, 700, and 800 are connected to the liquid crystal lines along with the signal lines G1-Gn, D1-Dm, SY1-SYβ, SX1-SXα and the thin film transistors Q and SQ. It may be integrated in the display panel assembly 300. In addition, the driving devices 400, 500, 550, 600, 700, and 800 may be integrated into a single chip, in which case at least one of them or at least one circuit element constituting them may be outside the single chip.

Next, the display operation and the detection operation of the liquid crystal display will be described in more detail.

First, the display operation of the liquid crystal display device will be described.

The signal controller 600 receives input image signals R, G, and B and an input control signal for controlling the display thereof from an external device (not shown). The input video signals R, G, and B contain luminance information of each pixel PX, and the luminance is a predetermined number, for example, 1024 (= 2 ¹⁰ ), 256 (= 2 ⁸ ), or 64 (= 2 ⁶ ) It has gray. Examples of the input control signal include a vertical sync signal Vsync, a horizontal sync signal Hsync, a main clock MCLK, and a data enable signal DE.

The signal controller 600 receives the input image signals R, G, and B based on the input image signals R, G, and B and the input control signal, and generates operating conditions of the liquid crystal panel assembly 300 and the image data driver 500. Process the image scan control signal CONT1, the image data control signal CONT2, the sensing data control signal CONT3, and the like, and then output the image scan control signal CONT1 to the image scan unit 400. The image data control signal CONT2 and the processed image signal DAT are sent to the image data driver 500, and the sensing data control signal CONT3 is sent to the detection signal processor 800.

The image scan control signal CONT1 includes a scan start signal STV indicating the start of scanning and at least one clock signal controlling the output of the gate-on voltage Von. The image scan control signal CONT1 may further include an output enable signal OE that defines a duration of the gate-on voltage Von.

The image data control signal CONT2 is a horizontal synchronization start signal STH indicating the start of transmission of the image data DAT in one pixel row and a load signal LOAD for applying the image data signal to the image data lines D1 -Dm. And a data clock signal HCLK. The image data control signal CONT2 is also an inversion signal for inverting the voltage polarity of the image data signal with respect to the common voltage Vcom (hereinafter referred to as the polarity of the image data signal by reducing the voltage polarity of the image data signal with respect to the common voltage). RVS) may be further included.

In response to the image data control signal CONT2 from the signal controller 600, the image data driver 500 receives the digital image signal DAT for the pixel PX of one pixel row, and each digital image signal DAT. By converting the digital image signal DAT into an analog image data signal by selecting a gray scale voltage corresponding to the < RTI ID = 0.0 > 1, < / RTI >

The image scanning unit 400 applies a gate-on voltage Von to the image scanning lines G1 -Gn according to the image scanning control signal CONT1 from the signal controller 600, and is connected to the image scanning lines G1 -Gn. The switching element Q is turned on. Then, the image data signal applied to the image data lines D1 -Dm is applied to the pixel PX through the turned on switching element Q.

The difference between the voltage of the image data signal applied to the pixel PX and the common voltage Vcom is shown as the charging voltage of the liquid crystal capacitor Clc, that is, the pixel voltage. The arrangement of the liquid crystal molecules varies according to the magnitude of the pixel voltage, thereby changing the polarization of light passing through the liquid crystal layer 3. The change in polarization is represented as a change in the transmittance of light by the polarizer attached to the liquid crystal panel assembly 300, and thus a desired image may be displayed.

This process is repeated in units of one horizontal period (also referred to as 1H "and equal to one period of the horizontal sync signal Hsync and the data enable signal DE), so that all image scanning lines G1 to Gn are repeated. In turn, the gate-on voltage Von is applied to apply an image data signal to all the pixels PX, thereby displaying an image of one frame.

When one frame ends, the next frame starts and the state of the inversion signal RVS applied to the image data driver 500 is controlled so that the polarity of the image data signal applied to each pixel PX is opposite to that of the previous frame. ("Frame inversion"). In this case, the polarity of the image data signal flowing through one image data line is changed (eg, inversion of a row, inversion of a point) according to the characteristics of the inversion signal RVS within one frame, or the polarity of the image data signal applied to one pixel row. May differ from one another (eg, nirvana, point inversion).

Next, a sensing operation of the liquid crystal display device will be described.

First, the operation of the sensing unit SU will be described.

When a pressure due to external stimulus such as a user's touch applied to the liquid crystal panel assembly 300 is applied to the common electrode display panel 200, the common electrode 270 of the common electrode display panel 200 and the thin film transistor array panel ( The distance between the pixel electrodes 191 of 100, that is, the distance between two terminals of the liquid crystal capacitor Clc is changed, so that the capacitance of the liquid crystal capacitor Clc of the capacitor unit CS of the sensing unit SU, which is a variable capacitor, changes. ((capacitance) is changed. At this time, since the capacitance of the reference capacitor (Cp) is constant, it is output from the contact between the reference capacitor (Cp) and the liquid crystal capacitor (Clc) according to the capacitance of the liquid crystal capacitor (Clc) that changes). The magnitude of the contact voltage Vs changes.

In this way, the contact voltage Vs that varies according to the capacitance of the liquid crystal capacitor Clc is applied to the control terminal of the amplifier AMP.

In the switching element SQ, which is an amplifier AMP, the degree of turn-on varies depending on the magnitude of the contact voltage Vp to be applied, and thus the amount of current flowing between the input terminal and the output terminal changes, and a voltage having a magnitude corresponding to the amount of current is a sensing data signal. It is output via the sense data lines SXl-SXα and SY1-SYβ.

The sensing signal processor 800 may detect the sensing data signal flowing along the sensing data lines SXl -SXα and SY1-SYβ in a porch section between the frames once every frame according to the sensing data control signal CONT3. Read In the porch section, since the sensing data signal is less affected by the driving signals from the image scanning unit 400, the image data driver 500, and the like, the reliability of the sensing data signal is increased. However, such a read operation is not necessarily performed every frame, and may be performed once every plurality of frames as necessary.

The sensing signal processor 800 converts the read analog sensing data signal into a digital sensing signal DSN after amplifying and filtering the signal and outputs the signal to the contact determination unit 700.

The touch determination unit 700 receives a digital sensing signal DSN, performs appropriate arithmetic processing to find out whether a contact is made and a contact position, and transmits the same to an external device, and the external device transmits the image signals R, G, and B based thereon. Transfer to the liquid crystal display device. As described above, in addition to the contact by the user's finger or the like, the image data signal transmitted through the connected data lines D1 -Dm is used to detect the liquid crystal capacitor Clc of the pixel PX whose charging capacity is changed. Is done. Accordingly, the touch determination unit 700 considers the image data signal applied to the data lines D1 to Dm in addition to the detection signals DSN from the respective sensing data lines SX1 to SXα and SY1 to SYβ. It is good to determine whether or not). To this end, a frame memory or the like is installed inside or outside the contact determining unit 700 to store an image signal for one frame, and then the contact determining unit 700 stores an image signal corresponding to the corresponding pixel on which the sensing unit SU is formed. After reading from the frame memory, it is possible to compare the applied sensing signals and determine whether the corresponding sensing unit is operated in consideration of the amount of change between the two signals.

As described above, the present invention senses whether a finger or the like touches by using the liquid crystal capacitor and the parasitic capacitor of the pixel, so that it is not necessary to design a separate accumulator that changes in capacitance due to contact or the like.

In the exemplary embodiment of the present invention, the liquid crystal display device is described as a display device, but the present invention is not limited thereto, and the same applies to a flat panel display device such as a plasma display device and an organic light emitting display device. Applicable

According to the present invention, a sensing unit for detecting the contact of a finger or the like is designed using a liquid crystal capacitor formed in a pixel and a parasitic capacitor having a constant capacitance, so that a separate capacitor or the like whose capacitance changes according to a pressure change by a finger or the like is designed. Since there is no need to form, the degree of freedom of design increases. In addition, as the space occupied by the sensing unit is reduced, a decrease in resolution due to the built-in sensing unit is reduced.

Furthermore, since the pixel electrode and the sensing switching element are formed using the contact portion for connecting the switching element of the pixel to the pixel electrode, it is not necessary to form a separate contact portion.

Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts of the present invention defined in the following claims are also provided. It belongs to the scope of rights.

Claims (9)

A first display panel having a first electrode, A second display panel facing the first display panel and having a second electrode; A liquid crystal layer formed between the first display panel and the second display panel, and Liquid crystal capacitors having the first electrode and the second electrode as two terminals Including, The second display panel, Multiple scanning lines, A plurality of image data lines intersecting the image scanning lines; A plurality of sensing data lines parallel to the image scanning line or the image data line; A plurality of first switching elements connected to the image scanning line, the image data line, and the second electrode, and A plurality of second switching elements connected to the second electrode and the sensing data line Liquid crystal display comprising a. In claim 1, And a plurality of voltage applying lines connected to each of the plurality of second switching elements to apply a driving voltage. In claim 1, The first electrode is a liquid crystal display device receives a predetermined voltage for reciprocating two values. In claim 3, And the predetermined voltage is a common voltage. In claim 1, The liquid crystal capacitor is a liquid crystal display device in which the capacitance changes due to pressure. In claim 5, The distance between the first electrode and the second electrode is changed by the pressure, and accordingly the capacitance of the liquid crystal capacitor is changed. In claim 1, And a plurality of variable capacitors connected to the second electrode and the first switching element. In claim 7, The variable capacitor maintains a constant capacitance. In claim 8, And the variable capacitor is a parasitic accumulator generated by the overlap of the second electrode and the image main line.

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