JP2010277461A - Touch panel, display panel, touch panel substrate, display panel substrate and display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a touch panel, a display panel, a touch panel substrate, a display panel substrate and a display device, with which erroneous detection due to external noises is eliminated. <P>SOLUTION: A light emitting side substrate 140 is a transparent substrate arranged on a side (observer's side) where light modulated by a liquid crystal layer 130 is emitted onto a liquid crystal display panel 60. The light emitting side substrate 140 includes in the order from the liquid crystal layer 130: an alignment film 121; a color filter 122; a transparent substrate 123; an adhesive layer 27; a detection electrode 25 and a shield electrode 26; a transparent substrate 24; and a polarizing plate 124. The detection electrode 25 and the shield electrode 26 are formed in the same layer (outermost surface of the liquid crystal panel 60), and the shield electrode 26 is provided around the detection electrode 25. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a touch panel capable of inputting information by touching an object such as a finger or a pen, a display panel, a touch panel substrate used in the touch panel, a display panel substrate used in the display panel, and a display device.

  Conventionally, a technique for inputting information by touching an object such as a finger is known. Among them, as a technology that attracts particular attention, there is a display device that enables the same information input as when a normal button is pressed with a finger by touching various buttons displayed on the display with an object such as a finger. Can be mentioned. Since this technology enables the common use of the display and buttons, it brings great benefits such as space saving and a reduction in the number of parts.

  There are various types of touch sensors that detect the contact of an object such as a finger. As a widely used touch sensor, for example, a capacitance type sensor can be cited. In this type, a change in the surface electric field of the panel caused by touching the touch panel with an object such as a finger is captured by a capacitive element, and the contact of the object such as a finger is detected.

JP 2008-9750 A

  By the way, the detection method described above is a method of reading a change in the surface electric field of the panel with a capacitive element. Therefore, when noise enters the capacitive element from the outside, the surface electric field of the panel changes due to the noise, and there is a possibility that the contact of an object such as a finger is erroneously detected. In particular, when the user of the display device is picking up external noise as an antenna, when the user touches the panel with an object such as a finger, the external noise is transmitted to the panel through the object such as a finger. There is a problem that the surface electric field of the panel changes, which causes false detection.

  The present invention has been made in view of such problems, and an object of the present invention is to provide a touch panel, a display panel, a touch panel substrate, a display panel substrate, and a display device that can eliminate erroneous detection caused by external noise. Is to provide.

  The touch panel substrate of the present invention includes a plurality of scan electrodes extending in a first direction, and a plurality of detection electrodes provided facing the plurality of scan electrodes and extending in a second direction intersecting the first direction. It is a board | substrate used for the touchscreen provided with these. The touch panel substrate includes a transparent substrate, a plurality of detection electrodes formed on one surface of the transparent substrate, and the same surface as the plurality of detection electrodes among the surfaces of the transparent substrate. And a shield electrode provided around.

  The display panel substrate of the present invention includes a plurality of pixel electrodes, a plurality of common electrodes provided to face the plurality of pixel electrodes and extending in the first direction, a display function layer having a display function, and a plurality of display electrodes. The substrate is used for a display panel provided with a plurality of detection electrodes provided opposite to the common electrode and extending in a second direction intersecting the first direction. The display panel substrate includes a transparent substrate, a plurality of detection electrodes formed on one surface of the transparent substrate, and a plurality of detection electrodes that are in the same plane as the plurality of detection electrodes among the surfaces of the transparent substrate. And a shield electrode provided around.

  The touch panel of the present invention includes a plurality of scan electrodes extending in a first direction and a plurality of detection electrodes provided facing the plurality of scan electrodes and extending in a second direction intersecting the first direction. It is provided. The touch panel further includes a shield electrode within the same plane as the plurality of detection electrodes and around the plurality of detection electrodes.

  The display panel of the present invention includes a plurality of pixel electrodes, a plurality of common electrodes provided facing the plurality of pixel electrodes and extending in the first direction, a display function layer having a display function, and a plurality of common electrodes. And a plurality of detection electrodes provided facing the electrodes and extending in a second direction intersecting the first direction. The display panel further includes a shield electrode within the same plane as the plurality of detection electrodes and around the plurality of detection electrodes.

  The first display device of the present invention includes a plurality of pixel electrodes, a plurality of common electrodes provided to face the plurality of pixel electrodes and extending in a predetermined direction, a display function layer having a display function, And a plurality of scan electrodes extending in the first direction. The display device includes a plurality of detection electrodes provided opposite to the plurality of scanning electrodes and extending in a second direction intersecting with the first direction, and in the same plane as the plurality of detection electrodes. And a shield electrode provided around the detection electrode. The display device further includes a first driving unit that applies a signal voltage corresponding to a video signal between the pixel electrode and the common electrode to exert a display function of the display function layer, and a selection pulse to the plurality of scanning electrodes. A second drive unit that sequentially applies in predetermined units and a detection unit that detects a contact position of an object based on detection signals obtained from a plurality of detection electrodes are provided.

  A second display device of the present invention includes a plurality of pixel electrodes, a plurality of common electrodes provided to face the plurality of pixel electrodes and extending in the first direction, and a display function layer having a display function. It is provided. The display device includes a plurality of detection electrodes that are provided to face a plurality of common electrodes and extend in a second direction intersecting the first direction, and are in the same plane as the plurality of detection electrodes. And a shield electrode provided around the detection electrode.

  In the touch panel substrate, the display panel substrate, the touch panel, the display panel, the first display device, and the second display device of the present invention, they are in the same plane as the plurality of detection electrodes and around the plurality of detection electrodes. A shield electrode is provided. Thereby, the detection electrode 25 is protected from external noise. For example, when a touch panel substrate, a display panel substrate, a display device including a touch panel or a display panel, the first display device, or the second display device is used in a mobile device, the mobile device is held by hand. When the user picks up external noise as an antenna and the picked up noise propagates through the user's hand, the application of the noise to the detection electrode is prevented by the shield electrode.

  According to the touch panel substrate, display panel substrate, touch panel, display panel, first display device, and second display device of the present invention, the application of external noise to the detection electrode is prevented by the shield electrode. As a result, erroneous detection due to external noise can be eliminated.

It is a figure for demonstrating the operation principle of the touch detection system used with the liquid crystal display device which concerns on embodiment of this invention, and is a figure which shows the state at the time of non-contact. It is a figure for demonstrating the principle of operation of the touch detection system used with the liquid crystal display device which concerns on embodiment of this invention, and is a figure which shows the state at the time of a finger contact. It is a figure for demonstrating the operation principle of the touch detection system used with the liquid crystal display device which concerns on embodiment of this invention, and is a figure which shows an example of the drive signal of a touch sensor, and the waveform of a detection signal. It is a figure which shows schematic structure of the liquid crystal display device which concerns on the 1st Embodiment of this invention. FIG. 5 is a diagram illustrating an example of a schematic configuration of a pixel in the liquid crystal display panel illustrated in FIG. 4. It is a figure which shows an example of the cross-sectional structure of the liquid crystal display panel shown in FIG. It is a figure which shows an example of the upper surface structure of the touch panel shown in FIG. It is a figure which expands and shows the touch panel shown in FIG. It is a figure which shows an example of the cross-sectional structure of the touch panel shown in FIG. It is a figure which shows the other example of the upper surface structure of the touchscreen shown in FIG. FIG. 5 is a diagram illustrating an example of a schematic configuration of a scanning line driving circuit illustrated in FIG. 4. FIG. 5 is a diagram illustrating an example of a schematic configuration of a detection circuit illustrated in FIG. 4. It is a figure which shows schematic structure of the liquid crystal display device which concerns on the 2nd Embodiment of this invention. It is a figure which shows an example of the cross-sectional structure of the liquid crystal display panel shown in FIG. It is a figure which shows the other example of a cross-sectional structure of the liquid crystal display panel shown in FIG. FIG. 14 is a diagram illustrating another example of a cross-sectional configuration of the liquid crystal display panel illustrated in FIG. 13. It is a figure which shows an example of the upper surface structure of the liquid crystal display panel shown in FIG. It is a figure which expands and shows the liquid crystal display panel shown in FIG. FIG. 14 is a diagram illustrating another example of a cross-sectional configuration of the liquid crystal display panel illustrated in FIG. 13. FIG. 20 is a diagram illustrating an example of a top surface configuration of the liquid crystal display panel illustrated in FIG. 19. FIG. 18 is a diagram illustrating another example of a top surface configuration of the liquid crystal display panel illustrated in FIG. 17. FIG. 21 is a diagram showing another example of a top surface configuration of the liquid crystal display panel shown in FIG. 20. It is a figure which shows the other example of schematic structure of the liquid crystal display device shown in FIG. FIG. 24 is a diagram illustrating an example of a top surface configuration of the liquid crystal display panel illustrated in FIG. 23. FIG. 24 is a diagram showing another example of the top surface configuration of the liquid crystal display panel shown in FIG. 23. It is a figure which shows the other example of schematic structure of the liquid crystal display device shown in FIG. It is a figure which shows an example of the cross-sectional structure of FPC shown in FIG. It is a perspective view showing the external appearance seen from the (A) front side in the application example 1 of display apparatuses, such as said each embodiment, and the external appearance seen from the (B) back side. (A) is a perspective view showing the external appearance seen from the front side of the application example 2, (B) is a perspective view showing the external appearance seen from the back side. 12 is a perspective view illustrating an appearance of application example 3. FIG. 14 is a perspective view illustrating an appearance of application example 4. FIG. (A) is a front view of the application example 5 in an open state, (B) is a side view thereof, (C) is a front view in a closed state, (D) is a left side view, and (E) is a right side view, (F) is a top view and (G) is a bottom view. It is a figure which shows the other example of the cross-sectional structure of the liquid crystal display device shown in FIG.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the invention will be described in detail with reference to the drawings. The description will be given in the following order.

1. 1. Basic principle of touch detection method First embodiment (example in which a touch panel is provided on the upper surface of a display panel)
3. Second embodiment (example in which a touch panel is provided inside the display panel)
4). 4. Modification of second embodiment Application examples

<Basic principle of touch detection method>
First, the basic principle of the touch detection method used in the display device of the following embodiment will be described. This touch detection method is embodied as a capacitive touch sensor. FIG. 1A schematically shows the touch sensor described above. FIG. 1B illustrates an equivalent circuit of the touch sensor in FIG. 1A and a peripheral circuit connected to the touch sensor. This touch sensor includes a dielectric 101 and a pair of electrodes 102 and 103 arranged to face each other with the dielectric 101 interposed therebetween. In an equivalent circuit, as shown in FIG. It is represented by element 104.

One end (electrode 102) of the capacitive element 104 is connected to the AC signal source 105. The other end (electrode 103) of the capacitor 104 is connected to the voltage detection circuit 106 and further connected to the reference potential line 108 via the resistor 107. AC signal source 105, and outputs the AC rectangular wave S _g of a predetermined frequency (for example, about several kHz~ dozen kHz). The voltage detection circuit 106 detects the peak value of the input signal, and further determines whether or not the finger touches the touch sensor based on the detected voltage. For example, the reference potential line 108 is electrically connected to a member (for example, a ground layer of a printed circuit board or a conductive casing) that supplies a potential that is a reference of circuit operation in a device on which a touch sensor is mounted. When connected to the member, it has the same potential (reference potential) as that member. The reference potential is, for example, a ground potential.

In this touch sensor, when an AC rectangular wave S _g (FIG. 3B) is applied from the AC signal source 105 to the electrode 102, an output waveform (detection signal) as shown in FIG. V _det ) appears.

In a state where an object such as a finger is not in contact with the touch sensor (FIG. 1A), as shown in FIG. 1B, the capacitance value of the capacitive element 104 is increased as the capacitive element 104 is charged / discharged. A corresponding current I ₀ flows. The potential waveform on the electrode 103 side of the capacitor 104 at this time is, for example, a waveform V _{0 in} FIG. 3A, and this is detected by the voltage detection circuit 106.

On the other hand, in a state where an object such as a finger is in contact with the touch sensor (FIG. 2A), the capacitor 109 formed by the object such as a finger is changed to the capacitor 104 as illustrated in FIG. Added in series. In this state, currents I ₁ and I ₂ flow with charge / discharge of the capacitive elements 104 and 109, respectively. At this time, the potential waveform at the electrode 103 is, for example, a waveform V _{1 in} FIG. 3A, which is detected by the voltage detection circuit 106. The potential of the electrode 103 is a divided potential determined by the values of the currents I ₁ and I ₂ flowing through the capacitive elements 104 and 109. For this reason, the waveform V ₁ is smaller than the waveform V ₀ in the non-contact state. Thereafter, the voltage detection circuit 106 compares the detection voltage with a predetermined threshold voltage V _th, and when the detection voltage is less than or equal to the threshold voltage V _th, it is determined that it is in a non-contact state, whereas when it is greater than the threshold voltage V _th The contact state is determined. In this way, touch detection is performed.

<First Embodiment>
FIG. 4 illustrates an example of a cross-sectional configuration of the liquid crystal display device 1 according to the first embodiment of the present invention. The liquid crystal display device 1 is a liquid crystal display device with a touch sensor, and includes a liquid crystal display element as a display element. Further, a capacitive touch sensor is separated from the liquid crystal display element on the surface of the liquid crystal display element. It is prepared by the body.

  For example, as shown in FIG. 4, the liquid crystal display device 1 includes a liquid crystal display panel 10, a touch panel 20, a backlight 30, and a peripheral circuit 40. The touch panel 20 is disposed on the viewer side (front side) of the liquid crystal display panel 10, and the backlight 30 is disposed behind the liquid crystal display panel 10.

[Liquid Crystal Display Panel 10]
The liquid crystal display panel 10 displays images by transmitting and modulating light from a light source (backlight 30) by changing the arrangement of liquid crystal molecules. The liquid crystal display panel 10 is, for example, a transmissive display panel in which a plurality of pixels 11 (see FIG. 5) arranged in a matrix are driven according to the video signal 40A. For example, as illustrated in FIG. 5, the liquid crystal display panel 10 includes a plurality of scanning lines WSL1 arranged in a row and a plurality of signal lines DTL arranged in a column. A plurality of pixels 11 are arranged in a matrix corresponding to the intersection between each scanning line WSL1 and each signal line DTL. In the liquid crystal display panel 10, for example, a plurality of common connection lines COM are arranged in rows. A plurality of common connection lines COM are arranged, for example, for each pixel 11 in one row.

  Each pixel 11 includes, for example, a liquid crystal element 12 and a transistor 13 as shown in FIG. One end of the liquid crystal element 12 is connected to the drain of the transistor 13, and the other end of the liquid crystal element 12 is connected to the common connection line COM. The gate of the transistor 13 is connected to the scanning line WSL1, and the source of the transistor 13 is connected to the signal line DTL. The liquid crystal element 12 modulates light passing therethrough according to the state of an electric field, and is provided in the liquid crystal display panel 10. The internal configuration of the liquid crystal element 12 will be described in detail later. The transistor 13 is for driving the liquid crystal element 12 and is configured by, for example, a TFT (Thin Film Transistor).

  For example, as shown in FIG. 6, the liquid crystal display panel 10 includes a liquid crystal layer 130, and a light incident side substrate 110 and a light emission side substrate 120 that are disposed to face each other with the liquid crystal layer 130 interposed therebetween. The liquid crystal layer 130 modulates light passing therethrough according to the state of the electric field, and includes, for example, liquid crystal molecules in a transverse electric field mode. Here, examples of the liquid crystal molecules in the transverse electric field mode include liquid crystal molecules in an FFS (fringe field switching) mode, liquid crystal molecules in an IPS (in-plane switching) mode, and the like.

  The light incident side substrate 110 is a transparent substrate disposed on the liquid crystal display panel 10 on the side on which light from the backlight 30 is incident (backlight 30 side). The light incident side substrate 110 includes, for example, a polarizing plate 111, a transparent substrate 112, a plurality of common electrodes 113, an insulating layer 114, a plurality of pixel electrodes 115, and an alignment film 116 in order from the backlight 30 side. On the other hand, the light emission side substrate 120 is a transparent substrate disposed on the side (observer side) where the light modulated by the liquid crystal layer 130 is emitted in the liquid crystal display panel 10. The light emission side substrate 120 includes, for example, an alignment film 121, a color filter 122, a transparent substrate 123, and a polarizing plate 124 in this order from the liquid crystal layer 130 side. Note that the color filter 122 may be omitted as necessary.

  Here, the liquid crystal element 12 described above corresponds to a portion facing the one pixel electrode 115 in the liquid crystal display panel 10 as indicated by a broken line in FIG. 6, for example. The liquid crystal element 12 includes, for example, a transparent substrate 112, a common electrode 113, an insulating layer 114, a pixel electrode 115, an alignment film 116, a liquid crystal layer 130, an alignment film 121, a color filter 122, and a transparent substrate 123 in this order. Yes.

  The polarizing plates 111 and 124 are a kind of optical shutter, and allow only light (polarized light) having a certain vibration direction to pass therethrough. These polarizing plates 111 and 124 are arranged in a crossed Nicols state. For example, the polarizing plate 111 is arranged so that the transmission axis is parallel to the column direction, and the polarizing plate 124 is arranged so that the transmission axis is parallel to the row direction. Thereby, the liquid crystal display panel 10 transmits or blocks the light emitted from the backlight 30 through the liquid crystal layer 130.

  The transparent substrates 112 and 123 are made of a substrate that is transparent to visible light, such as plate glass. On the transparent substrate 112, for example, an active driving circuit including the transistor 13, the signal line DTL, the scanning line WSL1, the common connection line COM, and the like is formed.

  The common electrode 113 and the pixel electrode 115 are made of a material transparent to visible light, for example, ITO (Indium Tin Oxide). The common electrode 113 forms the common connection line COM itself or a part of the common connection line COM. The plurality of common electrodes 113 have, for example, a band shape extending in the row direction and are arranged in parallel to each other. The common electrode 113 functions as, for example, a common electrode for the pixels 11 for each row. On the other hand, the plurality of pixel electrodes 115 are, for example, arranged in a lattice arrangement or a delta arrangement on the transparent substrate 112. For example, the pixel electrode 115 functions as an electrode for each pixel 11. For example, the pixel electrode 115 is arranged in parallel with a predetermined gap on a region facing the common electrode 113, and an electric field formed between the pixel electrode 115 and the common electrode 113 is lateral in the region of the liquid crystal layer 130. It faces the direction (row direction).

The insulating layer 114 is for insulating and separating the common electrode 113 and the pixel electrode 115 from each other, and is made of, for example, SiO ₂ . The alignment films 116 and 121 are made of a polymer material such as polyimide, for example, and have a function of aligning the liquid crystal contained in the liquid crystal layer 130. The alignment films 116 and 121 are, for example, rubbed so that the rubbing direction is parallel to one of the transmission axes of the polarizing plates 111 and 124. For example, the rubbing direction of the alignment films 116 and 121 Is parallel to the row direction (extending direction of the common electrode 113). The color filter 122 separates light transmitted through the liquid crystal layer 130 into, for example, three primary colors of red (R), green (G), and blue (B), or R, G, B, and white ( W) for color separation into four colors.

[Touch panel 20]
The touch panel 20 is for inputting information by touching the image display surface 1 </ b> A (the surface of the touch panel 20) of the liquid crystal display device 1 with a finger or a pen. The touch panel 20 is provided separately from the liquid crystal display panel 10, and is bonded to the surface of the liquid crystal display panel 10 via an adhesive (not shown), for example. The touch panel 20 corresponds to a specific example of the capacitive touch sensor described above, and detects contact / non-contact using an XY (matrix) matrix.

  FIG. 7 illustrates an example of a top surface configuration of the touch panel 20. FIG. 8 is an exploded perspective view of the touch panel 20 of FIG. In FIG. 8, an adhesive layer 23 described later is omitted. FIG. 9 illustrates an example of a cross-sectional configuration in the direction of arrows AA of the touch panel 20 illustrated in FIGS. 7 and 8. For example, as illustrated in FIGS. 7 to 9, the touch panel 20 includes a scanning side substrate 210 and a detection side substrate 220 that are disposed to face each other with an adhesive layer 23 interposed therebetween.

  The scanning side substrate 210 is a transparent substrate disposed on the side where the light from the liquid crystal display panel 10 is incident on the touch panel 20 (the liquid crystal display panel 10 side). The scanning side substrate 210 includes, for example, a transparent substrate 21 and a plurality of scanning electrodes 22 in order from the liquid crystal display panel 10 side. On the other hand, the detection-side substrate 220 is a transparent substrate disposed on the side (observer side) from which light transmitted through the touch panel 20 is emitted. For example, the detection-side substrate 220 includes a transparent substrate 24, a plurality of detection electrodes 25, and a shield electrode 26 in order from the liquid crystal display panel 10 side.

  Here, for example, a capacitive element is configured by the adhesive layer 23 and the transparent substrate 24, and the scanning electrode 22 and the detection electrode 25 disposed so as to face each other through the adhesive layer 23 and the transparent substrate 24. Therefore, the capacitive element functions as the capacitive touch sensor described above in the touch panel 20. In the touch panel 20, the arrangement order of the transparent substrate 21, the scanning electrode 22, the adhesive layer 23, the transparent substrate 24, the detection electrode 25, and the shield electrode 26 in the stacking direction is not limited to the above arrangement order. Therefore, the dielectric sandwiched between the electrodes in the capacitor element is not always the adhesive layer 23 and the transparent substrate 24.

  The transparent substrates 21 and 24 are made of a substrate transparent to visible light, for example, a light transmissive resin film. The scanning electrode 22, the detection electrode 25, and the shield electrode 26 are made of a material that is transparent to visible light, for example, ITO.

  The scanning electrode 22 corresponds to one electrode in the above-described capacitive element, and is electrically connected to the scanning line WSL2 (see FIG. 4). For example, the scanning electrode 22 is formed in contact with the surface of the transparent substrate 21. The plurality of scanning electrodes 22 have, for example, a strip shape extending in the row direction, and are arranged in parallel to each other. For example, each scanning electrode 22 extends in a direction parallel to each common electrode 113 in the liquid crystal display panel 10. A connection pad 22 </ b> A that connects to the peripheral circuit 40 is formed at one end of each scanning electrode 22.

  The detection electrode 25 corresponds to the other electrode in the above capacitive element, and is electrically connected to the detection line DET (see FIG. 4). The detection electrode 25 is formed in contact with the surface of the transparent substrate 24, for example. The plurality of detection electrodes 25 have, for example, a band shape extending in the column direction and are arranged in parallel to each other. Each detection electrode 25 extends, for example, in a direction orthogonal to the extending direction of each common electrode 113 and each scanning electrode 22. At one end of each detection electrode 25, a connection pad 25A connected to the peripheral circuit 40 is formed. Each connection pad 25A is preferably arranged near one common side of the surface of the transparent substrate 24, but if necessary, near the plurality of sides of the surface of the transparent substrate 24. It may be distributed. For example, as illustrated in FIG. 10, each connection pad 25 </ b> A may be disposed in the vicinity of two sides corresponding to each other on the surface of the transparent substrate 24.

  The shield electrode 26 is for protecting the detection electrode 25 from external noise. As the external noise, for example, when the liquid crystal display device 1 is used in a mobile device, a user holding the mobile device as an antenna picks up the external noise, and the picked up noise is the user's noise. The noise which invades through the hand.

  The shield electrode 26 is formed in the same plane as the detection electrode 25, and is formed in contact with the surface of the transparent substrate 24, for example. The shield electrode 26 is electrically connected to, for example, a member that applies a potential serving as a reference for circuit operation in the liquid crystal display device 1 and has the same potential (reference potential) as that member. The electrical connection between the shield electrode 26 and its member may be constant or only while the selection pulse is applied to the detection electrode 25. The shield electrode 26 may be electrically connected to a member having a predetermined fixed potential different from the reference potential, instead of the member that provides the reference potential.

  The shield electrode 26 is formed around the detection electrode 25. For example, as shown in FIG. 7, when each connection pad 25 </ b> A is disposed in the vicinity of one common side of the surface of the transparent substrate 24, the shield electrode 26 is included in the periphery of the detection electrode 25. It is arranged so as to surround the three sides where the connection pads 25A are not arranged. Further, for example, as shown in FIG. 10, when each connection pad 25 </ b> A is arranged in the vicinity of two sides corresponding to each other on the surface of the transparent substrate 24, the connection is made around the detection electrode 25. It is arranged so as to surround two sides where the pad 25A is not arranged. For example, when the user holds the mobile device on which the liquid crystal display device 1 is mounted in the hand, the shield electrode 26 is disposed in the gap between the end of the mobile device and the detection electrode 25 that the user's hand contacts. ing.

The shield electrode 26 is preferably disposed on the surface of the transparent substrate 24 other than the image display surface 1 </ b> A (outside the effective display area), for example, on the outer edge of the transparent substrate 24. Here, as shown in FIGS. 7 and 10, the distance between the shield electrode 26 and the detection electrode 25 (distance D _{1 in} the column direction and distance D _{2 in the} row direction) is equal to the two adjacent detection electrodes 25. distance D ₃ and either the same, or preferably it is greater than. In this case, the parasitic capacitance between the shield electrode 26 and the detection electrode 25 can be reduced, and the influence of the parasitic capacitance can be reduced when detecting contact / non-contact. Here, the “distance” refers to a distance at a position where the gap is minimum.

  The shield electrode 26 is preferably made of the same material as the detection electrode 25. In this case, in the manufacturing process, the shield electrode 26 and the detection electrode 25 can be formed at the same time. Compared to the case where the shield electrode 26 and the detection electrode 25 are made of different materials, the number of steps is reduced. And the number of masks can be reduced.

[Backlight 30]
The backlight 30 illuminates the liquid crystal display panel 10 from behind. For example, the light guide plate, a light source arranged on the side surface of the light guide plate, and an optical element arranged on the upper surface (light emission surface) of the light guide plate And. The light guide plate guides the light from the light source to the upper surface of the light guide plate.For example, the light guide plate has a predetermined patterned shape on at least one of the upper surface and the lower surface. It has the function of scattering and homogenizing. The light source is a linear light source, and includes, for example, a hot cathode fluorescent lamp (HCFL), CCFL, or a plurality of LEDs arranged in a row. The optical element is configured by laminating, for example, a diffusion plate, a diffusion sheet, a lens film, a polarization separation sheet, and the like.

[Peripheral circuit 40]
Next, each circuit in the peripheral circuit 40 will be described with reference to FIG. The peripheral circuit 40 drives the liquid crystal display panel 10 and the touch panel 20 and detects the output of the above-described capacitive touch sensor. For example, the peripheral circuit 40 is mounted on the light incident side substrate 110 in the liquid crystal display panel 10 or connected to a flexible printed wiring board (FPC) connected to the liquid crystal display panel 10 or the touch panel 20.

  The video signal processing circuit 41, for example, corrects the digital video signal 40A input from the outside, converts the corrected video signal into analog, and outputs the analog signal to the signal line drive circuit 43. The timing generation circuit 42 controls, for example, the signal line drive circuit 43 and the scanning line drive circuits 44 and 45 to operate in conjunction with each other. For example, the timing generation circuit 42 outputs a control signal 42A to these circuits in response to (in synchronization with) a synchronization signal 40B input from the outside.

  The signal line drive circuit 43 applies an analog video signal (a signal potential corresponding to the video signal 40A) input from the video signal processing circuit 41 to each signal line DTL, and applies the analog video signal to the pixel 11 to be selected. Is what you write. The signal line drive circuit 43 can output a signal potential corresponding to the video signal 40A, for example. The signal line driver circuit 43 can perform frame inversion driving in which, for example, a signal potential whose potential is inverted every frame period with respect to the reference potential is applied to each signal line DTL and is written in the pixel 11 to be selected. It has become. The frame inversion drive is for suppressing deterioration of the liquid crystal element 12 and is used as necessary. Further, for example, the signal line driving circuit 43 may perform 1H inversion driving in which a signal potential whose potential is inverted every 1H period with respect to the reference potential is applied to each signal line DTL and is written in the pixel 11 to be selected. It is possible. The 1H inversion drive is for suppressing the occurrence of flicker for each frame due to the inversion of the polarity of the voltage applied to the liquid crystal element 12, and is used as necessary. Here, the reference potential is a potential of the common connection line COM, for example, a ground potential.

  The scanning line driving circuit 44 sequentially applies a selection pulse to the plurality of scanning lines WSL1 in response to (in synchronization with) the input of the control signal 42A, and sequentially selects the plurality of pixels 11 in units of the scanning line WSL1. is there. The scanning line driving circuit 44 can output, for example, a voltage applied when the transistor 13 is turned on and a voltage applied when the transistor 13 is turned off.

  The scanning line driving circuit 45 sequentially applies selection pulses to the plurality of scanning lines WSL2 in response to the input of the control signal 42A (synchronously), and sequentially selects the plurality of scanning electrodes 22 in units of the scanning line WSL2. It is. The scanning line driving circuit 45 performs inversion driving for inverting the polarity of the voltage supplied to the scanning line WSL2 every predetermined period when the scanning electrode 22 is selected. For example, when the signal line driving circuit 43 performs 1H inversion driving, the scanning line driving circuit 45 generates a potential whose polarity with respect to the reference potential is opposite to the polarity with respect to the reference potential of the signal line DTL. 44 can be applied to the scanning line WSL2 corresponding to the pixel 11 to be selected.

For example, as illustrated in FIG. 11, the scanning line driving circuit 45 includes a switching element 45A connected to one end of the scanning line WSL2. The other end of the scanning line WSL2 is electrically connected to the scanning electrode 22 (connection pad 22A). One switching element 45A is provided for each scanning line WSL2, and has, for example, two input terminals. One input terminal of the switching element 45A, for example, is connected to an AC signal source 45B via the wiring L _1. AC signal source 45B is, for example, and outputs the AC rectangular wave S _g of a predetermined frequency (for example, about several kHz~ dozen kHz). Another input terminal of the switching element 45A, for example, are connected to the logic circuit 45C through the line L _2. The logic circuit 45C outputs, for example, a predetermined fixed potential (for example, a potential within a range of 0V to 5V). The AC signal source 45B and the logic circuit 45C are connected to the above-described reference potential line 108 as shown in FIG. 11, for example. The reference potential line 108 is, for example, a wiring connected to a member that provides a potential that is a reference for circuit operation in the liquid crystal display device 1. Note that the scanning line driving circuit 45 may be configured by a circuit different from the circuit illustrated in FIG.

Next, the detection circuit 46 will be described. FIG. 12 illustrates a configuration example of the detection circuit 46. The detection circuit 46 detects a contact position of an object such as a finger based on detection signals V _det obtained from the plurality of detection electrodes 25. Specifically, the detection circuit 46 first detects contact / non-contact of an object such as a finger to the image display surface 1 _{</ b> A} based on the detection signal V _det obtained from the detection electrode 25. When the detection circuit 46 detects that an object such as a finger has touched the image display surface 1A, the detection circuit 46 performs the following process. Specifically, the detection circuit 46 includes the image display surface 1A based on the application timing of the selection pulse output from the scanning line driving circuit 45 and the detection timing of the detection signal V _{det that is} equal to or lower than the threshold voltage V _th. The position where an object such as a finger contacts is calculated.

The detection circuit 46 includes, for example, an operational amplifier 51 for signal amplification, a low pass filter (LPF) 52 that cuts a high band and passes a low band, a high pass filter (HPF) 53 that passes a high band, and a rectifying and smoothing unit 54 and a comparator 55. The positive input terminal of the operational amplifier 51 (+) is connected the input terminal T _in is the input terminal T _in is electrically connected to the sensing electrode 25 (connection pads 25A). Therefore, to the input terminal T _in, so that the detection signal V _det is input. The output terminal of the operational amplifier 51 is connected to the rectifying / smoothing unit 54 via the LPF 52. An HPF 53 is connected to the LPF 52. For example, the LPF 52 has a configuration in which a resistor 52R and a capacitor 52C are connected in parallel, and the HPF 53 has a configuration in which a resistor 53R and a capacitor 53C are connected in series with the reference potential line 108, for example. The connection point between the LPF 52 and the HPF 53 is connected to the negative input terminal (−) of the operational amplifier 51. The rectifying / smoothing unit 54 includes, for example, a rectifying unit including a diode 54D for half-wave rectification and a smoothing unit including a resistor 54R and a capacitor 52C connected in parallel between the reference potential line 108. The output terminal of the rectifying / smoothing unit 54 is connected to the positive input terminal (+) of the comparator 55. A predetermined threshold voltage V _th (see FIG. 3) is input to the negative input terminal (−) of the comparator 55. An output terminal of the comparator 55 is connected to the output terminal T _out, the output terminal T _out is connected to the arithmetic circuit (not shown). Accordingly, predetermined information processing is performed by the arithmetic circuit based on the detection result (contact / non-contact) output from the output terminal _Tout .

The detection circuit 46 having such a configuration operates as follows. Detection signal V _det input to the input terminal T _in is amplified by the operational amplifier 51, the low-frequency component passes through the LPF 52, high frequency components are removed through the HPF 53. The low-frequency AC component that has passed through the LPF 52 is half-wave rectified by the diode 54 </ b> D of the rectifying / smoothing unit 54, smoothed to become a level signal, and input to the comparator 55. The comparator 55 compares the input level signal with the threshold voltage V _th, and when the level signal is equal to or lower than the threshold voltage V _th , the touch detection signal is output from the comparator 55. When the touch detection signal is input to the arithmetic circuit, the touch position is calculated in the arithmetic circuit based on the application timing of the selection pulse and the detection timing of the detection signal V _{det that is} equal to or lower than the threshold voltage V _th . The detection circuit 46 may be configured by a circuit different from the circuit described in FIG.

[Operation]
Next, an example of the operation of the liquid crystal display device 1 of the present embodiment will be described.

  In this liquid crystal display device 1, a signal potential corresponding to the video signal 40 </ b> A is applied to each signal line DTL by the signal line driving circuit 43, and a selection pulse corresponding to the control signal 42 </ b> A is scanned by the scanning line driving circuit 44. Sequentially applied to the line WSL1. Thereby, a lateral electric field having a magnitude corresponding to the signal potential is applied to the liquid crystal layer 130 for each pixel 11, and the liquid crystal molecules are aligned in a predetermined direction, so that the light from the backlight 30 is transmitted to the liquid crystal layer 130. In FIG. 5, the modulation is performed for each pixel 11 in accordance with the alignment direction of the liquid crystal molecules. As a result, an image is displayed on the image display surface 1A.

In the liquid crystal display device 1, the selection pulse is further sequentially applied to the plurality of scanning lines WSL 2 by the scanning line driving circuit 45. Then, the capacitive elements formed at the intersections of the scanning electrodes 22 and the detection electrodes 25 (capacitive elements corresponding to the above-described capacitive elements 104) are sequentially charged and discharged, and have a size corresponding to the capacitance value of the capacitive elements. A detection signal V _det is output from each of the plurality of detection electrodes 25. Outputs (detection signals V _det ) from the plurality of detection electrodes 25 are input to the detection circuit 46. When the user's finger or the like is not in contact with the surface of the touch panel 20, the magnitude of the detection signal V _det is substantially constant.

It is assumed that an object such as a user's finger contacts a location on the surface of the touch panel 20 at a certain time. Then, a capacitor element formed by an object such as a finger (a capacitor element corresponding to the above-described capacitor element 109) is added to the capacitor element formed at a position where an object such as a finger contacts. Therefore, the value of the detection signal V _det output from the detection electrode 25 when the selection pulse is applied to the scanning electrode 22 corresponding to the contact position is the detection output when the selection pulse is applied to another location. It becomes smaller than the value of the signal V _det . In the detection circuit 46, the detection signal V _det is compared with the threshold voltage V _th . For example, when the detection signal V _det is equal to or lower than the threshold voltage V _th , an object such as a finger contacts the surface of the touch panel 20. It is determined that The contact position is determined by the detection circuit 46 from the application timing of the selection pulse and the detection timing of the detection signal V _{det that is} equal to or lower than the threshold voltage V _th .

[effect]
Next, effects of the liquid crystal display device 1 of the present embodiment will be described.

In the present embodiment, due to the principle of the touch detection method, when a user's finger or the like touches the surface of the touch panel 20, a capacitive element formed by the finger or the like is added to the detection electrode 25 provided in the touch panel 20. It is necessary to Therefore, although the detection electrode 25 is provided on the surface of the touch panel 20 or in the vicinity thereof, external noise is easily applied to the detection electrode 25. In particular, when the liquid crystal display device 1 is used in a mobile device, a user holding the mobile device serves as an antenna to pick up external noise, and the picked up noise is detected through the user's hand. It may be applied to the electrode 25. When noise is applied to the detection electrode 25, the value of the detection signal V _det fluctuates due to the noise, so that there is a possibility that the detection circuit 46 erroneously determines contact / non-contact.

  However, in the present embodiment, the shield electrode 26 is provided around the detection electrode 25, and the detection electrode 25 is protected from external noise by the shield electrode 26. In particular, when the user holds the mobile device on which the liquid crystal display device 1 is mounted, the shield electrode 26 is disposed in the gap between the detection electrode 25 and the end of the mobile device that the user's hand contacts. Therefore, it is possible to effectively prevent noise that has propagated through the user's hand from being applied to the detection electrode 25. For example, when the user grasps a vertically long mobile device with his / her hand, the palm is on the back side of the mobile device, but the fingers are at the right and left ends of the mobile device. Further, for example, when the user holds the horizontally long mobile device with his / her hand, the left hand is at the left end of the mobile device and the right hand is at the right end of the mobile device. In any case, if the shield electrode 26 is provided at least in the gap between the right end of the mobile device and the detection electrode 25 and the gap between the left end of the mobile device and the detection electrode 25, the user's hand has been propagated. It can be seen that application of noise to the detection electrode 25 can be prevented. In the present embodiment, for example, as shown in FIGS. 7 and 10, the shield electrode 26 is provided on the left side and the right side of the detection electrode 25. Therefore, it is possible to effectively prevent the influence of external noise in the mobile device.

  In the present embodiment, the shield electrode 26 is formed in the same plane as the detection electrode 25. Therefore, when the shield electrode 26 and the detection electrode 25 are made of the same material, the shield electrode 26 and the detection electrode 25 can be formed simultaneously in the manufacturing process. As a result, the number of processes and the number of masks can be reduced as compared with the case where the shield electrode 26 and the detection electrode 25 are made of different materials.

<Second Embodiment>
Next, a liquid crystal display device 2 according to a second embodiment of the present invention will be described. In the following description, the same reference numerals are assigned to configurations common to the liquid crystal display device 1 of the above embodiment.

  The liquid crystal display device 2 of the present embodiment is a liquid crystal display device with a touch sensor, as in the above embodiment. The liquid crystal display device 2 includes a liquid crystal display element as a display element, and further includes a capacitive touch sensor inside the liquid crystal display element. That is, the liquid crystal display device 2 includes a touch sensor built-in type (in-cell type) liquid crystal display element. For example, as shown in FIG. 13, the liquid crystal display device 1 includes a liquid crystal display panel 60, a backlight 30, and a peripheral circuit 40.

[Liquid Crystal Display Panel 60]
The liquid crystal display panel 60 performs video display by transmitting and modulating light from a light source (backlight 30) by changing the arrangement of liquid crystal molecules. The liquid crystal display panel 60 is, for example, a transmissive display panel in which a plurality of pixels 11 arranged in a matrix are driven according to the video signal 40A. The liquid crystal display panel 60 has a plurality of scanning lines WSL1 arranged in a row and a plurality of signal lines DTL arranged in a row as shown in FIG. 5, for example, as in the above embodiment. ing. A plurality of pixels 11 are arranged in a matrix corresponding to the intersection between each scanning line WSL1 and each signal line DTL. In the liquid crystal display panel 60, for example, a plurality of common connection lines COM are arranged in rows. The plurality of common connection lines COM are arranged, for example, for each pixel 11 in one row, and are connected to a common line drive circuit 47 described later.

  For example, as shown in FIG. 14, the liquid crystal display panel 60 includes a liquid crystal layer 130, and a light incident side substrate 110 and a light emission side substrate 140 disposed to face each other with the liquid crystal layer 130 interposed therebetween. The light incident side substrate 110 is a transparent substrate disposed on the liquid crystal display panel 60 on the side on which light from the backlight 30 is incident (the backlight 30 side). The internal structure of the light incident side substrate 110 is the same as that in the above embodiment. On the other hand, the light emission side substrate 140 is a transparent substrate disposed on the side (observer side) where the light modulated by the liquid crystal layer 130 is emitted in the liquid crystal display panel 60. The light emission side substrate 140 is, for example, in order from the liquid crystal layer 130 side, an alignment film 121, a color filter 122, a transparent substrate 123, an adhesive layer 27, a detection electrode 25 and a shield electrode 26, a transparent substrate 24, And a polarizing plate 124. As in the above embodiment, the detection electrode 25 and the shield electrode 26 are formed in the same layer, and the shield electrode 26 is provided around the detection electrode 25.

  Note that the color filter 122 can be omitted as necessary. Further, as shown in FIG. 15, the transparent substrate 24 can be eliminated as necessary. In addition, as shown in FIG. 16, in order from the liquid crystal layer 130 side, a laminate including the adhesive layer 27, the detection electrode 25, the shield electrode 26, and the transparent substrate 24 is placed on the upper surface (observer side) of the polarizing plate 124. ). In any of the cases shown in FIGS. 14, 15, and 16, as shown in FIGS. 17 and 18, the detection electrode 25 and the shield electrode 26 are not exposed on the upper surface of the liquid crystal display panel 60.

  Note that FIG. 17 described above shows an example of a top surface configuration of the liquid crystal display panel 60. FIG. 18 mainly shows a portion corresponding to the electrode of the capacitive touch sensor in the liquid crystal display panel 60 of FIG.

  The liquid crystal display panel 60 has, for example, the common electrode 113 as one electrode of the capacitive touch sensor as shown in FIGS. 14, 17, and 18, and the scanning electrode of the above embodiment. 22 is not provided. In addition, the liquid crystal display panel 60 includes the detection electrode 25 as the other electrode of the capacitive touch sensor, as in the above embodiment. Furthermore, the liquid crystal display panel 60 includes, for example, an insulating layer 114, an alignment film 116, a liquid crystal layer 130, an alignment film 121, a color filter 122, a transparent substrate 123, and an adhesive layer 27, as shown in FIG. As a dielectric of the touch sensor of the type. In the liquid crystal display panel 60, the dielectric sandwiched between the pair of electrodes of the capacitive touch sensor may have a configuration different from the above.

  In the present embodiment, the common electrode 113 also serves as the scanning electrode 22 of the above embodiment, and is electrically connected to the common connection line COM. For example, the common electrode 113 is formed in contact with the surface of the transparent substrate 112. The plurality of common electrodes 113 have, for example, a band shape extending in the row direction and are arranged in parallel to each other. A connection pad 113A connected to the peripheral circuit 40 is formed at one end of each common electrode 113 (see FIG. 18). The detection electrode 25 and the shield electrode 26 have the same configuration as in the above embodiment.

[Peripheral circuit 40]
In the present embodiment, the peripheral circuit 40 has a scanning line driving circuit 47 instead of the scanning line driving circuit 45. The scanning line driving circuit 47 sequentially applies selection pulses to the plurality of common connection lines COM in response to the input of the control signal 42A, and sequentially selects the plurality of common electrodes 113 in units of the common connection line COM. To do. When the common electrode 113 is selected, the scanning line driving circuit 47 performs inversion driving in which the polarity of the voltage supplied to the common connection line COM is inverted every predetermined period. For example, when the signal line driving circuit 43 performs 1H inversion driving, the scanning line driving circuit 47 generates a potential whose polarity with respect to the reference potential is opposite to that of the signal line DTL with respect to the reference potential. 44 can be applied to the common connection line COM corresponding to the pixel 11 to be selected.

[Operation]
Next, an example of the operation of the liquid crystal display device 2 of the present embodiment will be described.

  In the liquid crystal display device 2, a signal potential corresponding to the video signal 40A is applied to each signal line DTL by the signal line driving circuit 43, and a selection pulse corresponding to the control signal 42A is scanned by the scanning line driving circuit 44. Sequentially applied to the line WSL1. Thereby, a lateral electric field having a magnitude corresponding to the signal potential is applied to the liquid crystal layer 130 for each pixel 11, and the liquid crystal molecules are aligned in a predetermined direction, so that the light from the backlight 30 is transmitted to the liquid crystal layer 130. In FIG. 5, the modulation is performed for each pixel 11 in accordance with the alignment direction of the liquid crystal molecules. As a result, an image is displayed on the image display surface 2A.

In the liquid crystal display device 2, the selection pulse is further sequentially applied to the plurality of common connection lines COM by the scanning line driving circuit 47. Then, capacitive elements formed at the intersections of the common electrode 113 and the detection electrode 25 (capacitive elements corresponding to the above-described capacitive element 104) are sequentially charged and discharged, and have a size corresponding to the capacitance value of the capacitive element. A detection signal V _det is output from each of the plurality of detection electrodes 25. Outputs (detection signals V _det ) from the plurality of detection electrodes 25 are input to the detection circuit 46. When the user's finger or the like is not in contact with the surface of the liquid crystal display panel 60, the magnitude of the detection signal V _det is almost constant.

It is assumed that a user's finger or the like has touched any place on the surface of the liquid crystal display panel 60 at some time. Then, a capacitor element formed by an object such as a finger (a capacitor element corresponding to the above-described capacitor element 109) is added to the capacitor element formed at a position where an object such as a finger contacts. Therefore, the value of the detection signal V _det output from the detection electrode 25 when the selection pulse is applied to the common electrode 113 corresponding to the contact position is the detection output when the selection pulse is applied to another location. It becomes smaller than the value of the signal V _det . The detection circuit 46 compares the detection signal V _det with the threshold voltage V _th . For example, when the detection signal V _det is equal to or lower than the threshold voltage V _th , a user's finger or the like is placed on the surface of the liquid crystal display panel 60. It is determined that they are touching. The contact position is determined by the detection circuit 46 from the application timing of the selection pulse and the detection timing of the detection signal V _{det that is} equal to or lower than the threshold voltage V _th .

[effect]
Next, effects of the liquid crystal display device 2 of the present embodiment will be described.

  In the present embodiment, a shield electrode 26 is provided around the detection electrode 25 as in the above embodiment, and the detection electrode 25 is protected from external noise by the shield electrode 26. For example, when the user holds the mobile device on which the liquid crystal display device 2 is mounted, the shield electrode 26 is disposed in the gap between the end of the mobile device and the detection electrode 25 that the user's hand contacts. Yes. Therefore, it is possible to effectively prevent noise that has propagated through the user's hand from being applied to the detection electrode 25.

  Also in the present embodiment, the shield electrode 26 is formed in the same plane as the detection electrode 25. Therefore, when the shield electrode 26 and the detection electrode 25 are made of the same material, the shield electrode 26 and the detection electrode 25 can be formed simultaneously in the manufacturing process. As a result, the number of processes and the number of masks can be reduced as compared with the case where the shield electrode 26 and the detection electrode 25 are made of different materials.

  In the present embodiment, a capacitive touch sensor is built in the liquid crystal display panel 60, and the common electrode 113 also serves as the scanning electrode 22 of the above embodiment. Therefore, the thickness of the liquid crystal display device 2 can be reduced as compared with the first embodiment.

<Modification of Second Embodiment>
In the second embodiment, the detection electrode 25 and the shield electrode 26 are not exposed on the upper surface of the liquid crystal display panel 60 and are provided under the polarizing plate 124 or the transparent substrate 24. However, for example, as shown in FIGS. 19 and 20 (a top view of FIG. 19), the detection electrode 25 and the shield electrode 26 may be exposed on the upper surface of the liquid crystal display panel 60. At this time, the detection electrode 25 and the shield electrode 26 are formed in the same layer as in the second embodiment, and the shield electrode 26 is provided around the detection electrode 25.

  Further, in the second embodiment and the modification thereof, for example, as shown in FIGS. 17 and 20, each connection pad 25 </ b> A has a common side of the surface of the polarizing plate 124 or the transparent substrate 24. The case where it arrange | positions in the vicinity was illustrated. However, the connection pads 25A may be distributed in the vicinity of a plurality of sides on the surface of the polarizing plate 124 or the transparent substrate 24 as necessary. For example, as illustrated in FIGS. 21 and 22, each connection pad 25 </ b> A may be disposed in the vicinity of two sides corresponding to each other on the surface of the transparent substrate 24.

  In the second embodiment and its modification, at least a part of the peripheral circuit 40 may be configured by a chip-like element such as an IC (Integrated Circuit). For example, as shown in FIG. 23, each of the signal line driving circuit 43 and the scanning line driving circuits 44 and 47 may be a chip-like element. In this case, each element can be mounted on the light incident side substrate 110, for example.

  As shown in FIG. 23, when the scanning line driving circuits 44 and 47 are arranged at the end in the row direction on the surface of the light incident side substrate 110, for example, as shown in FIG. The shield electrode 26 is preferably formed to extend over the scanning line drive circuits 44 and 47. In this case, the shield electrode 26 can block the noise generated from the scanning line driving circuits 44 and 47 from reaching the detection electrode 25 via the row direction end of the liquid crystal display panel 60. it can. Further, as shown in FIG. 25, the shield electrode 26 is formed not only on the scanning line drive circuits 44 and 47 but also on both ends of the common electrode 113 in the row direction. preferable. In this case, the noise generated from the transistor 13 or the like formed on the transparent substrate 110 reaches the detection electrode 25 through the gap between the common electrode 113 and the shield electrode 26. It can be blocked by the electrode 113.

In the modification of the second embodiment, as shown in FIGS. 23, 24, and 25, a plurality of connection pads 110A connected to wiring (not shown) drawn from the peripheral circuit 40 are provided. It may be provided at one end of the light incident side substrate 110. In this case, for example, as shown in FIG. 26, a flexible printed wiring board (FPC) 70 is connected to a plurality of connection pads 110A, and various signals such as a video signal 40A and a synchronization signal 40B are sent to the FPC 70. It becomes possible to input to the liquid crystal display panel 60 via the. Further, as shown in FIGS. 23, 24, and 25, a plurality of connection pads 25 </ b> A may be provided at one end of the light emission side substrate 140. In this case, for example, as shown in FIG. 26, a flexible printed wiring board (FPC) 80 is connected to the plurality of connection pads 25A, and the detection signal V _det is sent to the liquid crystal display panel 60 via the FPC 80. Can be taken out from. Accordingly, it is possible to provide the detection circuit 46 that requires a lot of calculations outside the liquid crystal display panel 60.

  Incidentally, the FPC 80 shown in FIG. 26 has a flexible base material 81 extending in one direction, for example, as shown in FIG. The base material 81 has a pair of end portions facing each other in the extending direction of the base material 81. One end portion has a width wider than the width of the central portion of the base material 81, for example, and can be connected to a plurality of connection pads 25A. The other end, for example, is wider than the width of the central portion of the base material 81, as in the case of one end. For example, the connection pad (not shown) of the printed circuit board on which the detection circuit 46 is mounted. ) Can be connected. The base material 81 is made of, for example, polyimide.

  On one surface of the base material 81, a plurality of wiring layers 82 made of, for example, copper foil are provided. The plurality of wiring layers 82 are formed in contact with one surface of the substrate 81 and are formed in the same plane. The plurality of wiring layers 82 are linearly formed from one end portion of the base material 81 to the other end portion. Furthermore, one end of the plurality of wiring layers 82 is connected to the plurality of connection pads 25A, and the other end of the plurality of wiring layers 82 is connected to a connection pad (not shown) on the printed circuit board on which the detection circuit 46 is mounted. It is connected.

  An insulating layer 83 is formed on the entire one surface of the substrate 81 including the plurality of wiring layers 82. The insulating layer 83 is for protecting the plurality of wiring layers 82. In addition, a shield layer made of, for example, copper foil is formed on at least one of the upper surface of the insulating layer 83 and the other surface of the substrate 81. Here, when the other surface of the base material 81 faces the upper surface side (the side opposite to the FPC 70), a shield layer 85 is formed on at least this surface, and the surface of the insulating layer 83 as necessary. Also, the shield layer 86 is formed. The shield layers 85 and 86 are for protecting the wiring layer 82 connected to the detection electrode 25 from external noise. Therefore, when the shield layer 85 is provided in the FPC 80, it is possible to prevent the noise that has propagated through the user's hand from being applied to the wiring layer 82, as with the shield electrode 26 of the above embodiment. On the other hand, when the shield layer 86 is provided in the FPC 80, it is possible to prevent noise generated from the transistor 13 and the signal line driving circuit 43 formed on the transparent substrate 110 from reaching the wiring layer 82. .

<Application example>
Next, with reference to FIGS. 28 to 32, application examples of the display device with a touch sensor described in the above embodiment and the modification will be described. The display device in the above embodiment and the like can be applied to electronic devices in various fields such as a television device, a digital camera, a laptop personal computer, a mobile terminal device such as a mobile phone, or a video camera. In other words, the display device according to the above-described embodiment or the like can be applied to electronic devices in various fields that display an externally input video signal or an internally generated video signal as an image or video.

(Application example 1)
FIG. 28 illustrates an appearance of a television device to which the display device of each of the above embodiments is applied. The television apparatus has, for example, a video display screen unit 300 including a front panel 310 and a filter glass 320, and the video display screen unit 300 is configured by the display device according to each of the above embodiments. .

(Application example 2)
FIG. 29 shows the appearance of a digital camera to which the display device of each of the above embodiments is applied. The digital camera includes, for example, a flash light emitting unit 410, a display unit 420, a menu switch 430, and a shutter button 440. The display unit 420 is configured by the display device according to each of the above embodiments. Yes.

(Application example 3)
FIG. 30 shows an appearance of a notebook personal computer to which the display device of each of the above embodiments is applied. The notebook personal computer has, for example, a main body 510, a keyboard 520 for inputting characters and the like, and a display unit 530 for displaying an image. The display unit 530 is a display according to each of the above embodiments. It is comprised by the apparatus.

(Application example 4)
FIG. 31 shows the appearance of a video camera to which the display device of each of the above embodiments is applied. This video camera has, for example, a main body 610, a subject photographing lens 620 provided on the front side surface of the main body 610, a start / stop switch 630 at the time of photographing, and a display 640. Reference numeral 640 denotes the display device according to each of the above embodiments.

(Application example 5)
FIG. 32 shows the appearance of a mobile phone to which the display device of each of the above embodiments is applied. For example, the mobile phone is obtained by connecting an upper housing 710 and a lower housing 720 with a connecting portion (hinge portion) 730, and includes a display 740, a sub-display 750, a picture light 760, and a camera 770. Yes. The display 740 or the sub-display 750 is configured by the display device according to each of the above embodiments.

  The present invention has been described above with reference to the embodiment and its modifications and application examples. However, the present invention is not limited to the embodiment and the like, and various modifications can be made.

  For example, in the above-described embodiment and its modifications, an insulating protective member that covers the upper surfaces of at least the plurality of detection electrodes 25 and the shield electrode 26 may be provided. Specifically, a cover plate that covers the upper surface of the liquid crystal display panels 10 and 60 or the touch panel 20, a housing that covers the liquid crystal display panels 10 and 60, or the touch panel 20 may be provided. For example, as shown in FIG. 33, a housing 90 that covers the liquid crystal display panel 60 can be provided. The housing 90 is made of, for example, an insulating material. As shown in FIG. 33, when the detection electrode 25 and the shield electrode 26 are provided on the outermost surface of the liquid crystal display panel 60, the housing 90 is electrically separated from the detection electrode 25 and the shield electrode 26. Has been.

  In the above-described embodiment and the like, the case where a transmissive element is used as the liquid crystal display element has been described. However, other than the transmissive element, for example, a reflective element can be used. However, in that case, it is necessary to eliminate the light source (backlight 30) or to dispose it on the upper surface side of the liquid crystal display element.

  In the above-described embodiments and the like, the case where the present invention is applied to a display device using a liquid crystal display element as a display element has been described. However, the display device using other display elements, for example, organic EL elements, is used. Is also applicable.

  The series of processes described in the above embodiments can be performed by hardware or can be performed by software. When a series of processing is performed by software, a program constituting the software is installed in a general-purpose computer or the like. Such a program can be recorded in advance in a recording medium built in the computer.

DESCRIPTION OF SYMBOLS 1, 2 ... Liquid crystal display device, 1A, 2A ... Image display surface 10, 60 ... Liquid crystal display panel, 11 ... Pixel, 12 ... Liquid crystal element, 13 ... Transistor, 20 ... Touch panel, 21, 24 ... Transparent substrate, 22 ... Scan electrode, 22A, 25A, 110A ... connection pad, 23, 27 ... adhesive layer, 25 ... detection electrode, 26 ... shield electrode, 30 ... backlight, 40 ... peripheral circuit, 40A ... video signal, 40B ... synchronization signal, 41 ... Video signal processing circuit 42. Timing generating circuit 42 A Control signal 43 Signal line drive circuit 44 45 45 Scan line drive circuit 45 A Switching element 45 B 105 105 AC signal source 45 C Logic circuit 46 ... Detection circuit 51 ... Operational amplifier 52 ... LPF 52C, 53C, 54C ... Capacitor 52R, 53R, 54R, 107 ... Resistance 53 ... HPF, 54 ... rectifying / smoothing part, 54D ... diode, 55 ... comparator, 70,80 ... FPC, 81 ... substrate, 82 ... wiring layer, 83,114 ... insulating layer, 84,85 ... shielding layer, 90 ... Case: 101: Dielectric, 102, 103: Electrode, 104, 109: Capacitance element, 106: Voltage detection circuit, 108: Reference potential line, 110: Incident side substrate, 111, 124: Deflection plate, 112, 123 ... Transparent substrate 113 ... Common electrode 115 ... Pixel electrode 116,121 ... Alignment film 120,140 ... Light emission side substrate 122 ... Color filter 210 ... Scanning side substrate 220 ... Detection side substrate 300 ... Video display Screen unit, 310 ... front panel, 320 ... filter glass, 410 ... light emitting unit, 420, 530, 640 ... display unit, 430 ... menu switch, 440 ... Tatter button, 510 ... main body, 520 ... keyboard, 610 ... main body, 620 ... lens, 630 ... start / stop switch, 710 ... upper housing, 720 ... lower housing, 730 ... connecting portion, 740 ... display, 750 ... Sub display, 760 ... Picture light, 770 ... Camera, COM ... Common line, D ₁ , D ₂ , D ₃ ... Distance, DET ... Detection line, DTL ... Signal line, L ₁ , L ₂ ... Wiring, T _in ... Input Terminal, T _out ... Output terminal, V _det ... Detection signal, V _th ... Threshold voltage, WSL1, WSL2 ... Scanning line.

Claims (14)

A touch panel comprising: a plurality of scan electrodes extending in a first direction; and a plurality of detection electrodes provided opposite to the plurality of scan electrodes and extending in a second direction intersecting the first direction. A touch panel substrate used,
A transparent substrate;
The plurality of detection electrodes formed on one surface of the transparent substrate;
A touch panel substrate comprising: a shield electrode provided in the same plane as the plurality of detection electrodes on the surface of the transparent substrate and provided around the plurality of detection electrodes. Each of the detection electrodes has a connection pad electrically connected to an external circuit at an end thereof,
Each of the connection pads is disposed in the vicinity of one common side of the transparent substrate,
The touch panel substrate according to claim 1, wherein the shield electrode is disposed so as to surround three sides of the plurality of detection electrodes where the connection pads are not disposed. Each of the detection electrodes has a connection pad electrically connected to an external circuit at an end thereof,
Each connection pad is disposed in the vicinity of two sides corresponding to each other in the transparent substrate,
The touch panel substrate according to claim 1, wherein the shield electrode is disposed so as to surround two sides of the plurality of detection electrodes where the connection pads are not disposed. The touchscreen substrate according to any one of claims 1 to 3, wherein the shield electrode is made of the same material as the plurality of detection electrodes. A plurality of pixel electrodes, a plurality of common electrodes provided facing the plurality of pixel electrodes and extending in the first direction, a display function layer having a display function, and facing the plurality of common electrodes A display panel substrate used for a display panel provided with a plurality of detection electrodes provided in a second direction intersecting the first direction,
A transparent substrate;
The plurality of detection electrodes formed on one surface of the transparent substrate;
A display panel substrate, comprising: a shield electrode provided in the same plane as the plurality of detection electrodes on the surface of the transparent substrate and provided around the plurality of detection electrodes. Each of the detection electrodes has a connection pad electrically connected to an external circuit at an end thereof,
Each of the connection pads is disposed in the vicinity of one common side of the transparent substrate,
The display panel substrate according to claim 5, wherein the shield electrode is disposed so as to surround three sides of the plurality of detection electrodes where the connection pads are not disposed. Each of the detection electrodes has a connection pad electrically connected to an external circuit at an end thereof,
Each connection pad is disposed in the vicinity of two sides corresponding to each other in the transparent substrate,
The display panel substrate according to claim 5, wherein the shield electrode is disposed so as to surround two sides of the plurality of detection electrodes where the connection pads are not disposed. The display panel substrate according to claim 5, wherein the shield electrode is made of the same material as the plurality of detection electrodes. A plurality of scan electrodes extending in a first direction;
A plurality of detection electrodes provided opposite to the plurality of scan electrodes and extending in a second direction intersecting the first direction;
A touch panel comprising: a shield electrode provided in the same plane as the plurality of detection electrodes and around the plurality of detection electrodes. A plurality of pixel electrodes;
A plurality of common electrodes provided facing the plurality of pixel electrodes and extending in a first direction;
A display function layer having a display function;
A plurality of detection electrodes provided opposite to the plurality of common electrodes and extending in a second direction intersecting the first direction; and the plurality of detection electrodes are in the same plane as the plurality of detection electrodes. A display panel comprising a shield electrode provided around the electrode. The display panel according to claim 10, wherein the shield electrode is disposed in a non-opposing region with the plurality of pixel electrodes. A plurality of pixel electrodes;
A plurality of common electrodes provided facing the plurality of pixel electrodes and extending in a predetermined direction;
A display function layer having a display function;
A plurality of scan electrodes extending in a first direction;
A plurality of detection electrodes provided opposite to the plurality of scan electrodes and extending in a second direction intersecting the first direction;
A shield electrode provided in the same plane as the plurality of detection electrodes and around the plurality of detection electrodes;
A first driver that applies a signal voltage corresponding to a video signal between the pixel electrode and the common electrode to exert a display function of the display function layer;
A second driving unit that sequentially applies a selection pulse to the plurality of scan electrodes in a predetermined unit;
And a detection unit that detects a contact position of an object based on detection signals obtained from the plurality of detection electrodes. A plurality of pixel electrodes;
A plurality of common electrodes provided facing the plurality of pixel electrodes and extending in a first direction;
A display function layer having a display function;
A plurality of detection electrodes provided opposite to the plurality of common electrodes and extending in a second direction intersecting the first direction;
A shield electrode provided in the same plane as the plurality of detection electrodes and around the plurality of detection electrodes;
A signal voltage corresponding to a video signal is applied between the pixel electrode and the common electrode to exhibit the display function of the display function layer, and a selection pulse is sequentially applied to the plurality of common electrodes in a predetermined unit. A drive unit;
And a detection unit that detects a contact position of an object based on detection signals obtained from the plurality of detection electrodes. The display device according to claim 13, further comprising an insulating protection member that covers at least the upper surfaces of the plurality of detection electrodes and the shield electrode.

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