JP2022170309A - Liquid crystal display device - Google Patents

Abstract

To provide a liquid crystal display device with which touch sensor wiring is facilitated and sensor sensitivity can be improved.SOLUTION: The liquid crystal display device includes: a first and a second substrate 10, 11 that are arranged face to face; a liquid crystal layer 20 sandwiched between the first and second substrates 10, 11; a plurality of sensor electrodes 13 provided on the first substrate 10; a first insulating layer 22 provided on the plurality of sensor electrodes 13; a plurality of wirings TL provided on the first insulating layer 22 so as to correspond to the plurality of sensor electrodes 13, and extending in a first direction; a plurality of contacts 14 for connecting the plurality of sensor electrodes 13 and the plurality of wirings TL, respectively; a second insulating layer 27 provided on the plurality of wirings TL; a plurality of pixel electrodes 18 provided on the second insulation layer 27 as to correspond to a plurality of pixels; a color filter 29 provided on the second substrate 11; and a common electrode 15 provided on the color filter 29.SELECTED DRAWING: Figure 5

Description

The present invention relates to a liquid crystal display device.

An in-cell liquid crystal display device is known in which a touch sensor for detecting a user's touch position is incorporated in the display panel. In this liquid crystal display device, a common electrode for supplying a common voltage to the pixels of the liquid crystal display panel is divided into a plurality of common electrodes, and these common electrodes are also used as touch sensor electrodes. A common voltage is supplied to the multiple common electrodes during the image display period, and a touch drive signal for touch detection is supplied to the multiple common electrodes during the touch detection period.

In liquid crystal display devices such as IPS (In-Plane Switching) mode and FFS (Fringe Field Switching) mode, a common electrode is provided on an array substrate on which a TFT array is arranged. Then, on the array substrate, the touch sensor electrode also serving as a common electrode and the integrated circuit are wired.

On the other hand, in a VA (Vertical Alignment) mode liquid crystal display device, a common electrode is provided on a color filter substrate on which color filters are arranged. Therefore, when wiring the touch sensor electrode, which also serves as a common electrode, and the integrated circuit, it is necessary to wire between the two substrates across the liquid crystal layer.

Japanese Patent No. 5670991

The present invention provides a liquid crystal display device in which wiring of touch sensors is easy and sensor sensitivity can be improved.

According to the first aspect of the present invention, first and second substrates are arranged to face each other, a liquid crystal layer is sandwiched between the first and second substrates, and a plurality of sensor electrodes are provided on the first substrate. a first insulating layer provided on the plurality of sensor electrodes; a plurality of wirings provided on the first insulating layer so as to correspond to the plurality of sensor electrodes and extending in a first direction; a plurality of contacts respectively connecting the plurality of sensor electrodes and the plurality of wirings; a second insulating layer provided on the plurality of wirings; and a plurality of pixels on the second insulating layer corresponding to each other. A liquid crystal display device is provided, comprising a plurality of provided pixel electrodes, a color filter provided on the second substrate, and a common electrode provided on the color filter.

According to a second aspect of the present invention, the liquid crystal display according to the first aspect further comprises a detection circuit provided on the first substrate, connected to the plurality of wirings, and configured to detect changes in capacitance of the plurality of sensor electrodes. An apparatus is provided.

A third aspect of the present invention provides the liquid crystal display device according to the first or second aspect, wherein the second substrate is arranged on the backlight side.

A fourth aspect of the present invention provides the liquid crystal display device according to the third aspect, further comprising a backlight for irradiating illumination light toward the second substrate.

A fifth aspect of the present invention provides the liquid crystal display device according to any one of the first to fourth aspects, wherein the plurality of pixel electrodes and the plurality of sensor electrodes form auxiliary capacitances.

A sixth aspect of the present invention provides the liquid crystal display device according to any one of the first to fifth aspects, wherein the liquid crystal layer is of a vertical alignment type.

According to the present invention, it is possible to provide a liquid crystal display device in which wiring of a touch sensor is easy and sensor sensitivity can be improved.

FIG. 1 is a block diagram of a liquid crystal display device according to an embodiment of the invention. FIG. 2 is a circuit diagram of a pixel array included in the liquid crystal display panel. FIG. 3 is a layout diagram of the liquid crystal display panel. FIG. 4 is a layout diagram of a plurality of pixels and a plurality of sensor electrodes. FIG. 5 is a cross-sectional view of the liquid crystal display panel.

Hereinafter, embodiments will be described with reference to the drawings. However, the drawings are schematic or conceptual, and the dimensions and proportions of each drawing are not necessarily the same as the actual ones. Also, even when the same parts are shown in the drawings, there are cases in which the dimensional relationships and ratios are shown differently. In particular, several embodiments shown below are examples of apparatuses and methods for embodying the technical idea of the present invention, and the technical idea of the present invention can be is not specified. In the following description, elements having the same functions and configurations are denoted by the same reference numerals, and overlapping descriptions are omitted.

[1] Configuration of Liquid Crystal Display Device 1 The liquid crystal display device 1 according to the embodiment of the present invention is an in-cell type in which a touch sensor is built in between two glass substrates. Further, as a touch sensor method, a projective capacitance method that detects a change in capacitance according to a touch operation is used.

FIG. 1 is a block diagram of a liquid crystal display device 1 according to an embodiment of the invention. The liquid crystal display device 1 includes a liquid crystal display panel 2 , an illumination device 3 , a scanning line drive circuit 4 , a signal line drive circuit 5 , a common electrode drive circuit 6 , a touch detection circuit 7 , a voltage generation circuit 8 and a control circuit 9 .

The liquid crystal display panel 2 has a pixel array in which a plurality of pixels PX are arranged in a matrix. The liquid crystal display panel 2 is provided with a plurality of scanning lines GL1 to GLm each extending in the row direction and a plurality of signal lines SL1 to SLn each extending in the column direction. "m" and "n" are each an integer of 2 or more. Pixels PX are arranged in intersection regions between the scanning lines GL and the signal lines SL.

A lighting device (also referred to as a backlight) 3 is a surface light source that irradiates the back surface of the liquid crystal display panel 2 with light. As the backlight 3, for example, a direct type or sidelight type (edge light type) LED backlight is used.

A scanning line driving circuit (also referred to as scanning line driver) 4 is electrically connected to a plurality of scanning lines GL. The scanning line driving circuit 4 sends scanning signals for turning on/off switching elements included in the pixels PX to the liquid crystal display panel 2 based on control signals sent from the control circuit 9 .

A signal line driving circuit (also referred to as a signal line driver) 5 is electrically connected to a plurality of signal lines SL. The signal line drive circuit 5 receives control signals and display data from the control circuit 9 . The signal line driving circuit 5 sends a signal (driving voltage) corresponding to display data to the liquid crystal display panel 2 based on the control signal.

A common electrode driving circuit (also referred to as a common electrode driver) 6 generates a common voltage Vcom and supplies the common voltage Vcom to common electrodes in the liquid crystal display panel 2 .

The touch detection circuit 7 drives a plurality of sensor electrodes (touch sensor electrodes) built in the liquid crystal display panel 2 . The configuration of the sensor electrodes built into the liquid crystal display panel 2 will be described later. The touch detection circuit 7 detects changes in capacitance of the plurality of sensor electrodes, and also detects the position touched by the user on the display screen.

The voltage generation circuit 8 generates various voltages necessary for the operation of the liquid crystal display device 1 and supplies them to the corresponding circuits.

The control circuit 9 comprehensively controls the operation of the liquid crystal display device 1 . The control circuit 9 receives image data DT and a control signal CNT from the outside. The control circuit 9 generates various control signals based on the image data DT and sends these control signals to the corresponding circuits.

FIG. 2 is a circuit diagram of the pixel array 2A included in the liquid crystal display panel 2. As shown in FIG. The X direction in FIG. 2 is the row direction in which scanning lines extend, and the Y direction is the column direction in which signal lines extend.

The pixel PX includes a switching element (active element) 17, a liquid crystal capacitor (liquid crystal element) Clc, and a storage capacitor Cs. As the switching element 17, for example, a TFT (Thin Film Transistor) is used, or an n-channel TFT is used. Note that although the source and drain of a transistor change depending on the direction of current flowing through the transistor, an example of the connection state of the transistor will be described below. However, it goes without saying that the source and drain are not fixed as the name suggests.

The TFT 17 has a source connected to the signal line SL, a gate connected to the scanning line GL, and a drain connected to one electrode of the liquid crystal capacitor Clc. A liquid crystal capacitor Clc as a liquid crystal element is composed of a pixel electrode, a common electrode, and a liquid crystal layer sandwiched therebetween. A common electrode driving circuit 6 applies a common voltage Vcom to the other electrode of the liquid crystal capacitor Clc.

One electrode of the storage capacitor Cs is connected to one electrode of the liquid crystal capacitor Clc. A common electrode driving circuit 6 applies a common voltage Vcom to the other electrode of the storage capacitor Cs. The storage capacitor Cs has a function of suppressing the potential fluctuation occurring in the pixel electrode and holding the drive voltage applied to the pixel electrode until the drive voltage corresponding to the next signal is applied. The storage capacitor Cs is composed of a pixel electrode, a storage capacitor line, and an insulating layer sandwiched therebetween. A storage capacitor voltage different from the common voltage Vcom may be applied to the other electrode (storage capacitor line) of the storage capacitor Cs.

[2] Configuration of Liquid Crystal Display Panel 2 Next, the configuration of the liquid crystal display panel 2 will be described. FIG. 3 is a layout diagram of the liquid crystal display panel 2. As shown in FIG.

The liquid crystal display panel 2 includes a TFT substrate 10 on which switching elements (TFTs) and pixel electrodes are formed, and a color filter substrate (referred to as a CF substrate) 11 arranged opposite to the TFT substrate 10 and on which color filters and the like are formed. Prepare. Each of the TFT substrate 10 and the CF substrate 11 is composed of a transparent and insulating substrate (for example, a glass substrate or a plastic substrate). The TFT substrate 10 and the CF substrate 11 are bonded using a sealing material 12 . The area surrounded by the sealing material 12 is the display area.

The TFT substrate 10 is provided with a plurality of sensor electrodes 13 arranged in a matrix. A plurality of sensor electrodes 13 are arranged to fill the display area. The planar shape of the sensor electrode 13 is, for example, a quadrangle.

The TFT substrate 10 is provided with a plurality of sensor lines TL each extending in the Y direction. The plurality of sensor wirings TL are provided corresponding to the plurality of sensor electrodes 13, respectively. The plurality of sensor wirings TL are electrically connected to the plurality of sensor electrodes 13 via the plurality of contacts 14, respectively.

An integrated circuit (IC) 16 is provided on the TFT substrate 10 . The integrated circuit 16 includes the scanning line driving circuit 4, the signal line driving circuit 5, the common electrode driving circuit 6, the touch detection circuit 7, the voltage generation circuit 8, and the control circuit 9 shown in FIG. The integrated circuit 16 is configured by, for example, TDDI (Touch Display Driver Integration) in which a touch sensor driver and an image display driver are integrated and integrated. The plurality of sensor wirings TL are drawn out to the integrated circuit 16 and electrically connected to the integrated circuit 16 (specifically, the touch detection circuit 7).

A common electrode 15 is provided on the CF substrate 11 . The common electrode 15 is planarly provided over the entire display area. The common electrode 15 functions as an electrode for driving the pixels PX.

FIG. 4 is a layout diagram of a plurality of pixels PX and a plurality of sensor electrodes 13. As shown in FIG. The area of the sensor electrode 13 is larger than the area of the pixel PX, and one sensor electrode 13 is arranged so as to overlap a plurality of pixels PX. FIG. 4 shows four sensor electrodes 13-1 to 13-4 for simplification.

One sensor electrode 13 is arranged so as to overlap a plurality of pixels PX. In the example of FIG. 4, one sensor electrode 13 has an area overlapping with 18 (6×3) pixels PX.

The sensor electrodes 13-1 to 13-4 are electrically connected to sensor wirings TL1 to TL4 via contacts 14-1 to 14-4, respectively.

A pixel PX includes a switching element 17 and a pixel electrode 18 . Scanning lines GL1 to GL6 and signal lines SL1 to SL12 are arranged in the pixel array.

(Cross-sectional structure of liquid crystal display panel 2)
FIG. 5 is a cross-sectional view of the liquid crystal display panel 2. As shown in FIG. FIG. 5 shows an extracted portion corresponding to one pixel PX. FIG. 5 is a cross-sectional view of one pixel PX cut along the Y direction.

The liquid crystal display panel 2 includes a TFT substrate 10 , a CF substrate 11 and a liquid crystal layer 20 . In this embodiment, of the TFT substrate 10 and the CF substrate 11, the CF substrate 11 is arranged closer to the backlight 3, and the illumination light from the backlight 3 enters the liquid crystal display panel 2 from the CF substrate 11 side.

The liquid crystal layer 20 is sandwiched and filled between the TFT substrate 10 and the CF substrate 11 . Specifically, the liquid crystal layer 20 is enclosed within a display area surrounded by the TFT substrate 10 , the CF substrate 11 and the sealing material 12 . The sealing material 12 is made of, for example, an ultraviolet curable resin, a thermosetting resin, or an ultraviolet/heat curable resin. be hardened.

The liquid crystal material forming the liquid crystal layer 20 changes its optical properties by manipulating the orientation of the liquid crystal molecules according to the applied electric field. The liquid crystal display panel 2 of this embodiment is, for example, a VA mode using vertical alignment (VA) type liquid crystal. Negative (N-type) nematic liquid crystal having negative dielectric anisotropy is used as the liquid crystal layer 20 . The liquid crystal layer 20 is vertically aligned in the initial state (when no electric field is applied). Liquid crystal molecules are oriented substantially perpendicularly to the main surface of the substrate when no voltage (no electric field) is present. When voltage is applied (electric field is applied), the directors of the liquid crystal molecules are tilted in the horizontal direction (direction parallel to the main surface of the substrate).

First, the structure of the TFT substrate 10 will be described. A sensor electrode 13 is provided on the liquid crystal layer 20 side of the TFT substrate 10 . The layout of the plurality of sensor electrodes 13 is as shown in FIGS. 3 and 4. FIG.

An insulating layer 21 is provided on the sensor electrode 13 and the TFT substrate 10 .

A gate electrode GL extending in the X direction is provided on the insulating layer 21 . The gate electrode GL functions as a scanning line. A plurality of pixels for one row arranged in the X direction are commonly connected to one scanning line. A gate insulating film (also referred to as an insulating layer) 22 is provided on the TFT substrate 10 and the gate electrode GL.

A semiconductor layer 23 is provided on the gate insulating film 22 for each pixel. For example, amorphous silicon is used as the semiconductor layer 23 . The type of TFT 17 is not particularly limited. In this embodiment, an etching stopper type TFT will be described as an example. FIG. 5 shows an etching stopper type TFT. In the etching stopper type TFT, a protective film 24 (for example, a silicon oxide film) is formed on the semiconductor layer 23, and the source electrode and the drain electrode are processed using the protective film 24 as an etching stopper.

A source electrode 25 and a drain electrode 26 separated from each other in the Y direction are provided on the semiconductor layer 23 and the gate insulating film 22 . Between the source electrode 25 and the semiconductor layer 23, an n ⁺ -type semiconductor layer into which a high-concentration n-type impurity is introduced may be provided in order to improve electrical connection therebetween. Similarly, an n ⁺ -type semiconductor layer may be provided between the drain electrode 26 and the semiconductor layer 23 .

A sensor wiring TL extending in the Y direction is provided on the gate insulating film 22 . The sensor wiring TL is arranged at the boundary between two pixels adjacent in the X direction. The sensor wiring TL is electrically connected to the sensor electrode 13 via the contact 14 .

Although not shown, a signal line SL extending in the Y direction is provided on the gate insulating film 22 . The signal line SL is arranged at the boundary between two pixels adjacent in the X direction. A plurality of pixels for one column arranged in the Y direction are commonly connected to one signal line SL. The source electrode 25 is electrically connected to the signal line SL.

An insulating layer 27 is provided on the source electrode 25 , the drain electrode 26 , the sensor wiring TL, and the gate insulating film 22 .

A pixel electrode 18 is provided on the insulating layer 27 . The area of the pixel electrode 18 is set slightly smaller than the area of the pixel PX. The pixel electrode 18 is electrically connected to the drain electrode 26 via the contact 28 .

An alignment film (not shown) for controlling the alignment of the liquid crystal layer 20 is provided on the pixel electrode 18 and the insulating layer 27 . The alignment film vertically aligns the liquid crystal molecules in the initial state of the liquid crystal layer 20 .

Next, the configuration on the CF substrate 11 side will be described. A color filter 29 is provided on the liquid crystal layer 20 side of the CF substrate 11 . The color filter 29 includes a red filter 29R, a green filter 29G, and a blue filter 29B. A general color filter is composed of red (R), green (G), and blue (B), which are the three primary colors of light. A set of three adjacent colors of R, G, and B is a display unit (pixel), and a single color portion of one of R, G, and B in one pixel is a minimum called a sub-pixel (sub-pixel). It is a driving unit. A TFT 17 and a pixel electrode 18 are provided for each sub-pixel. In the description of this specification, sub-pixels are referred to as pixels unless there is a particular need to distinguish between pixels and sub-pixels. Arbitrary arrangements including a stripe arrangement, a mosaic arrangement, and a delta arrangement can be applied as the arrangement of the color filters. Adjacent ones of the red filter 29R, the green filter 29G, and the blue filter 29B are in contact with each other. In this specification, the red filter 29R, the green filter 29G, and the blue filter 29B are simply referred to as the color filter 29 when there is no particular need to distinguish them.

A light shielding layer (also called black matrix or black mask) 30 is provided on the CF substrate 11 on the side of the liquid crystal layer 20 . A black matrix 30 is arranged at the boundary of the pixels. The black matrix 30 is arranged so as to cover the TFTs 17, the signal lines SL, and the sensor lines TL in plan view. The black matrix 30 is formed, for example, in a mesh shape so as to surround the pixels. The black matrix 30 has a function of shielding unnecessary light generated at the boundaries of pixels and improving contrast.

A common electrode 15 is provided on the color filter 29 . The common electrode 15 is planarly formed over the entire display area of the liquid crystal display panel 2 .

A protrusion 31 is provided on the common electrode 15 for each pixel. The planar shape of the protrusion 31 is, for example, a circle. The protrusions 31 have a function of controlling the orientation of the liquid crystal layer 20 (that is, the direction in which liquid crystal molecules fall) when a voltage is applied.

An alignment film (not shown) for controlling the alignment of the liquid crystal layer 20 is provided on the common electrode 15 and the protrusions 31 . The alignment film vertically aligns the liquid crystal molecules in the initial state of the liquid crystal layer 20 .

A polarizing plate 32 is provided on the side of the TFT substrate 10 opposite to the liquid crystal layer 20 . A polarizing plate 33 is provided on the side of the CF substrate 11 opposite to the liquid crystal layer 20 . The polarizing plates 32 and 33 are, for example, circularly polarizing plates. A circularly polarizing plate is configured by laminating a retardation plate and a linear polarizer. The retardation plate is composed of a quarter-wave plate (λ/4 plate). λ means wavelength. The slow axis of the retardation plate is set at approximately 45 degrees with respect to the transmission axis of the linear polarizer. The liquid crystal display panel 2 is, for example, normally black mode. In this case, the transmission axis of the polarizing plate 32 is set so as to be substantially orthogonal to the transmission axis of the polarizing plate 33 .

(Examples of materials)
As the gate electrode GL, the source electrode 25, the drain electrode 26, the signal line SL, the sensor wiring TL, and the contact 14, for example, aluminum (Al), molybdenum (Mo), chromium (Cr), or tungsten (W). , or an alloy containing one or more of these is used.

The pixel electrode 18, the contact 28, the common electrode 15, and the sensor electrode 13 are made of a transparent conductive material such as ITO (indium tin oxide).

As the insulating layer 21, the gate insulating film 22, and the insulating layer 27, a transparent insulating material such as silicon nitride (SiN) is used.

[3] Operation The operation of the liquid crystal display device 1 configured as described above will be described.

The backlight 3 emits illumination light toward the liquid crystal display panel 2 . Illumination light from the backlight 3 enters the liquid crystal display panel 2 from the CF substrate 11 side of the liquid crystal display panel 2 and passes through the liquid crystal layer 20 .

A common voltage Vcom is applied to the common electrode 15 by the common electrode driving circuit 6 . The common voltage Vcom is 0V, for example. The OFF state is a state in which no electric field is applied to the liquid crystal layer 20 , and the same common voltage Vcom as the common electrode 15 is applied to the pixel electrode 18 . The ON state is a state in which an electric field is applied to the liquid crystal layer 20 and a positive voltage is applied to the pixel electrode 18 . A positive voltage is a voltage equal to or higher than the threshold voltage of the liquid crystal layer. In practice, inversion driving (AC driving) is performed to invert the polarity of the electric field between the pixel electrode 18 and the common electrode 15 at predetermined intervals. By performing inversion driving, deterioration of the liquid crystal can be suppressed. The cycle of inversion drive can be set arbitrarily.

In the off-state, the liquid crystal molecules are set to the initial state, ie the long axes of the liquid crystal molecules are oriented vertically. Light incident on the liquid crystal display panel 2 is circularly polarized after passing through the polarizing plate 32 and enters the liquid crystal layer 20 . The light incident on the liquid crystal layer 20 is hardly affected by birefringence in the liquid crystal layer 20 and passes through the liquid crystal layer 20 while maintaining the state of circularly polarized light. The light transmitted through the liquid crystal layer 20 enters the polarizing plate 33 . The light incident on the polarizing plate 33 cannot pass through the polarizing plate 33, that is, the liquid crystal display panel 2 displays black (that is, normally black mode).

In the ON state, the liquid crystal molecules are horizontally oriented, ie, the long axes of the liquid crystal molecules are oriented approximately horizontally. Light incident on the liquid crystal display panel 2 is circularly polarized after passing through the polarizing plate 32 and enters the liquid crystal layer 20 . The polarization state of the light incident on the liquid crystal layer 20 changes due to the birefringence of the liquid crystal layer 20 . Therefore, part of the light transmitted through the liquid crystal layer 20 is transmitted through the polarizing plate 33, that is, the liquid crystal display panel 2 provides white display or color display.

Next, operation of the touch sensor will be described. The touch sensor is, for example, self-capacitance.

The touch detection circuit 7 applies sensor drive voltages to the plurality of sensor lines TL. As a result, the sensor drive voltage is applied to the plurality of sensor electrodes 13 and touch sensing is performed by the plurality of sensor electrodes 13 . Sensor signals corresponding to the sensing results of the plurality of sensor electrodes 13 are sent to the touch detection circuit 7 via the plurality of sensor wirings TL.

When an object to be detected such as a user's finger or a touch pen touches the display screen of the liquid crystal display panel 2, a capacitance is generated between the sensor electrode 13 and the object to be detected. increases the parasitic capacitance of In this case, the current increases when the sensor drive voltage is supplied to the sensor electrode 13 . The touch detection circuit 7 detects the touch position based on the variation of this current. A plurality of sensor electrodes 13 are arranged in a matrix in the display area. Therefore, the touch detection circuit 7 can detect the position touched by the user on the display screen.

The sensor sensitivity of the capacitive touch sensor is determined according to the distance between the sensor (sensor electrode) and an object to be sensed, such as a user's finger or touch pen. In this embodiment, the sensor electrodes 13 are provided on the TFT substrate 10, and the TFT substrate 10 is arranged on the display screen side. Thereby, sensor sensitivity can be improved.

In this embodiment, the multiple sensor electrodes 13 also function as storage capacitor electrodes. That is, the sensor electrode 13, the pixel electrode 18, and the insulating layer sandwiched between them form a storage capacitor Cs. Therefore, in this embodiment, it is not necessary to newly provide a storage capacitor line for forming a storage capacitor.

[4] Effect of the Embodiment According to the present embodiment, the plurality of sensor electrodes 13, the plurality of sensor wirings TL, and the integrated circuit 16 (including the touch detection circuit 7) are all provided on the TFT substrate 10. FIG. Therefore, wiring between the plurality of sensor electrodes 13 and the integrated circuit 16 is facilitated.

Moreover, it is not necessary to wire the wiring of the touch sensor across the liquid crystal layer. Therefore, the sensor wiring TL can be shortened. Thereby, sensor sensitivity can be improved.

The CF substrate 11 is arranged on the backlight 3 side, and the TFT substrate 10 is arranged on the display screen side, that is, on the side close to the surface touched by the user. The sensor electrode 13 is provided on the TFT substrate 10 on the side touched by the user. Therefore, the sensor electrode 13 can be arranged closer to the object to be detected. Thereby, the sensitivity of the touch sensor can be improved.

There is a technique in which a common electrode is divided into a plurality of parts and used as sensor electrodes. In this case, it is necessary to operate the image display device and the touch sensor in a time-sharing manner, for example. In contrast, in this embodiment, the sensor electrode 13 and the common electrode 15 are arranged separately. Thereby, the area and shape of the sensor electrode 13 can be freely designed. Also, the operation of the touch sensor can be easily controlled.

In the above embodiment, the case of using the self-capacitance method as the touch sensor has been described, but the plurality of sensor electrodes 13 may be driven using the mutual capacitance method.

In each of the embodiments described above, the VA mode is taken as an example of the liquid crystal mode. The liquid crystal mode may be a TN (Twisted Nematic) mode, an ECB (Electrically Controlled Birefringence) mode, an STN (Super Twisted Nematic) mode, or the like.

The present invention is not limited to the above-described embodiments, and can be modified in various ways without departing from the scope of the present invention at the implementation stage. Further, each embodiment may be implemented in combination as appropriate, in which case the combined effect can be obtained. Furthermore, various inventions are included in the above embodiments, and various inventions can be extracted by combinations selected from a plurality of disclosed constituent elements. For example, even if some constituent elements are deleted from all the constituent elements shown in the embodiments, if the problem can be solved and effects can be obtained, the configuration with the constituent elements deleted can be extracted as an invention.

DESCRIPTION OF SYMBOLS 1... Liquid crystal display device, 2... Liquid crystal display panel, 2A... Pixel array, 3... Lighting device, 4... Scanning line drive circuit, 5... Signal line drive circuit, 6... Common electrode drive circuit, 7... Touch detection circuit, 8 Voltage generating circuit 9 Control circuit 10 TFT substrate 11 CF substrate 12 Sealing material 13 Sensor electrode 14 Contact 15 Common electrode 16 Integrated circuit 17 Switching element 18 20 Liquid crystal layer 21 Insulating layer 22 Gate insulating film 23 Semiconductor layer 24 Protective film 25 Source electrode 26 Drain electrode 27 Insulating layer 28 Contact 29 ... color filter, 30 ... light shielding layer, 31 ... projection, 32, 33 ... polarizing plate.

Claims (6)

first and second substrates arranged to face each other;
a liquid crystal layer sandwiched between the first and second substrates;
a plurality of sensor electrodes provided on the first substrate;
a first insulating layer provided on the plurality of sensor electrodes;
a plurality of wires provided on the first insulating layer so as to correspond to the plurality of sensor electrodes and extending in a first direction;
a plurality of contacts respectively connecting the plurality of sensor electrodes and the plurality of wirings;
a second insulating layer provided on the plurality of wirings;
a plurality of pixel electrodes provided on the second insulating layer so as to correspond to a plurality of pixels;
a color filter provided on the second substrate;
a common electrode provided on the color filter;
A liquid crystal display device comprising: 2. The liquid crystal display device according to claim 1, further comprising a detection circuit provided on said first substrate, connected to said plurality of wirings, and detecting a change in capacitance of said plurality of sensor electrodes. 3. The liquid crystal display device according to claim 1, wherein the second substrate is arranged on the backlight side. 4. The liquid crystal display device according to claim 3, further comprising a backlight that irradiates illumination light toward the second substrate. 5. The liquid crystal display device according to claim 1, wherein the plurality of pixel electrodes and the plurality of sensor electrodes constitute auxiliary capacitors. The liquid crystal display device according to any one of claims 1 to 5, wherein the liquid crystal layer is of a vertical alignment type.

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