JP7221618B2 - Display device - Google Patents

Description

The present invention relates to display devices, and is particularly applicable to display devices having a touch detection function.

A display panel having a touch sensor is used in smartphones, tablet terminals, and the like. A display panel having this type of touch sensor may detect and recognize capacitance variations due to noise or the like, for example. Such recognition based on capacitance variation due to noise or the like is called erroneous touch recognition (touch ghost).

JP 2016-177343 A JP 2015-228053 A JP 2015-69469 A

An object of the present invention is to provide a display device capable of avoiding erroneous touch recognition.

Other problems and novel features will become apparent from the description of the specification and the accompanying drawings.

A brief outline of a representative one of the present invention is as follows.

That is, the display device includes an array substrate, a counter substrate, a flexible circuit substrate connected to the counter substrate, a touch detection control section provided on the array substrate or on the flexible circuit substrate, It includes touch detection electrodes provided on the counter substrate, lead wirings, and first detection wirings. The touch detection electrodes are connected to the touch detection control unit by the lead wires through the flexible circuit board. The first detection wiring is arranged adjacent to the lead wiring and connected to the touch detection control section.

Further, the display device includes an array substrate, a counter substrate, a flexible circuit substrate connected to at least one of the counter substrate and the array substrate, and arranged on the flexible circuit substrate or on the array substrate. and a detection wiring provided on the flexible circuit board and connected to the control unit.

Further, the display device includes: a first substrate; a second substrate facing the first substrate and provided with a plurality of touch detection electrodes; a first flexible circuit substrate connected to the first substrate; A second flexible circuit board connected to two boards, and a touch detection control unit provided on the first board or on the first flexible circuit board. The second flexible circuit board includes: a plurality of lead wires electrically connected to the plurality of touch detection electrodes; and a second flexible circuit board arranged adjacent to the plurality of lead wires and not connected to any of the plurality of touch detection electrodes. 1 detection wiring; The plurality of extraction wirings and the first detection wiring are connected to the touch detection control section.

1 is a diagram showing a schematic configuration of a display device in a sensor-equipped display device DSP according to an embodiment; FIG. 1 is a cross-sectional view showing the structure of a sensor-equipped display device DSP according to an embodiment; FIG. It is a figure which shows the typical basic composition of the mutual detection system of display apparatus DSP with a sensor which concerns on embodiment. 1 is a diagram showing a typical basic configuration of a self-detection method according to an embodiment; FIG. It is a figure for demonstrating the driving method of the mutual detection system of the display apparatus DSP with a sensor which concerns on embodiment. It is a figure for demonstrating the self-detection system and the driving method of the display apparatus DSP with a sensor which concerns on embodiment. 1 is a diagram illustrating a schematic configuration of a display device according to an embodiment; FIG. It is a figure explaining the touch detection function of the display apparatus which concerns on embodiment. FIG. 7 is a diagram showing a partially enlarged view of FIG. 6; FIG. 10 is a diagram showing an arrangement example 1 of lead wirings and first detection wirings; FIG. 11 is a diagram showing an arrangement example 2 of lead wirings and first detection wirings; It is a figure explaining other schematic structures of the display apparatus which concerns on embodiment. 3 is a circuit diagram showing a detection method when first detection wiring 3 and shield wiring SHL are set at a fixed potential (reference potential); FIG. FIG. 10 is a circuit diagram showing a detection method when the first detection wiring 3 and the shield wiring SHL are driven by a signal having the same phase as that of the detection electrodes Rx (active guard driving); 3 is a circuit diagram showing a detection method when the first detection wiring 3 and the shield wiring SHL are driven by a self-detection circuit; FIG. 4 is a diagram conceptually showing the relationship between the first detection wiring and the noise source; FIG. 4 is a diagram conceptually showing the relationship between the first detection wiring and the noise source; FIG. It is a figure which shows the 1st touch coordinate detection method which concerns on embodiment. It is a figure which shows the 2nd touch coordinate detection method which concerns on embodiment. FIG. 8B is a cross-sectional view showing the first state of the arrangement example 1 shown in FIG. 8A; FIG. 8B is a cross-sectional view showing a second state of the arrangement example 1 shown in FIG. 8A; FIG. 8B is a cross-sectional view showing a third state of the arrangement example 1 shown in FIG. 8A; 8B is a cross-sectional view showing a fourth state of the arrangement example 1 shown in FIG. 8A; FIG. FIG. 8C is a cross-sectional view showing a first state of the arrangement example 2 shown in FIG. 8B; FIG. 8C is a cross-sectional view showing a second state of the arrangement example 2 shown in FIG. 8B; FIG. 8C is a cross-sectional view showing a third state of the arrangement example 2 shown in FIG. 8B; FIG. 8C is a cross-sectional view showing a fourth state of the arrangement example 2 shown in FIG. 8B; It is a figure explaining other schematic structures of the display apparatus which concerns on the aspect of embodiment. 17 is a cross-sectional view conceptually showing a state in which the flexible printed circuit board of the display device shown in FIG. 16 is bent; FIG. FIG. 10 is a diagram showing another arrangement example of lead wirings and first detection wirings; It is a figure explaining other schematic structures of the display apparatus which concerns on the aspect of embodiment. FIG. 4 is a cross-sectional view showing a bent state of the flexible printed circuit board FPC1; FIG. 4 is a cross-sectional view showing a state in which a gap between the backlight BLT and the flexible printed circuit board FPC1 is opened; FIG. 4 is a cross-sectional view showing a state in which a space between the shield sheet SHLS and the flexible printed circuit board FPC1 is opened; FIG. 10 is a diagram illustrating still another schematic configuration of the display device according to the embodiment; FIG. 22 is a diagram showing the back surface of the display device when the flexible printed circuit board FPC1 of FIG. 21 is folded; FIG. 22 is a cross-sectional view conceptually showing a state in which the flexible printed circuit board of the display device shown in FIG. 21 is bent; It is a figure which shows the detection method which detects peeling of a flexible printed circuit board.

Each embodiment of the present invention will be described below with reference to the drawings.

It should be noted that the disclosure is merely an example, and those skilled in the art will naturally include within the scope of the present invention any appropriate modifications that can be easily conceived while maintaining the gist of the invention. In addition, in order to make the description clearer, the drawings may schematically show the width, thickness, shape, etc. of each part compared to the actual embodiment, but this is only an example, and the interpretation of the present invention is not intended. It is not limited.

In addition, in this specification and each figure, the same reference numerals may be given to the same elements as those described above with respect to the existing figures, and detailed description thereof may be omitted as appropriate.

In this embodiment, a liquid crystal display device is disclosed as an example of the display device. This liquid crystal display device can be used, for example, in various devices such as smart phones, tablet terminals, mobile phone terminals, personal computers, television receivers, in-vehicle devices, and game machines.

In the present specification and claims, expressions such as “above” and “below” when describing the drawings express the relative positional relationship between the structure of interest and other structures. there is Specifically, when viewed from the side, the direction from the first substrate (array substrate) to the second substrate (counter substrate) is defined as "up", and the opposite direction is defined as "down".

Also, the terms “inner” and “outer” indicate the relative positional relationship between the two parts with respect to the display area. That is, "inner side" refers to the side relatively close to the display area with respect to one part, and "outside" refers to the side relatively far from the display area with respect to one part. However, the definitions of "inner side" and "outer side" as used herein refer to the state in which the liquid crystal display device is not folded.

A “display device” refers to general display devices that display images using a display panel. A "display panel" refers to a structure that displays images using an electro-optic layer. For example, the term display panel may refer to a display cell including an electro-optic layer, or to a structure in which other optical members (e.g., polarizing member, backlight, touch panel, etc.) are attached to the display cell. In some cases. Here, the "electro-optical layer" may include a liquid crystal layer, an electrochromic (EC) layer, and the like, as long as there is no technical contradiction. Therefore, the embodiments described later will be described by exemplifying a liquid crystal panel including a liquid crystal layer as a display panel, but application to display panels including other electro-optical layers described above is not excluded.

(embodiment)
FIG. 1 is a diagram showing a schematic configuration of a display device in a sensor-equipped display device DSP according to an embodiment. In addition, in the embodiment, the display device is a liquid crystal display device.

The sensor-equipped display device DSP includes a display panel PNL and a backlight BLT that illuminates the display panel PNL from the back side. The display panel PNL is provided with a display portion including display pixels PX arranged in a matrix.

As shown in FIG. 1, in the display section, gate lines G (G1, G2, . Source lines S (S1, S2, . there is Each of the plurality of display pixels PX has a pixel electrode PE and a common electrode COME, and has a liquid crystal layer between the opposing pixel electrode PE and common electrode. A plurality of common electrodes COME extending in the row direction (X) are arranged in the column direction (Y). A plurality of common electrodes COME extending in the column direction (Y) may be arranged in the row direction (X).

The pixel switch SW includes a thin film transistor (TFT). A gate electrode of the pixel switch SW is electrically connected to the corresponding gate line G. A source electrode of the pixel switch SW is electrically connected to the corresponding source line S. A drain electrode of the pixel switch SW is electrically connected to the corresponding pixel electrode PE.

Further, gate drivers GD (left GD-L and right GD-R), a source driver SD, and a common electrode driving circuit CD are provided as driving means for driving the plurality of display pixels PX. A plurality of gate lines G are electrically connected to output portions of gate drivers GD, respectively. Each of the plurality of source lines S is electrically connected to the output section of the source driver SD. The common electrode COME is electrically connected to the output section of the common electrode drive circuit CD. In FIG. 1, the source driver SD and the common electrode drive circuit CD are depicted as being provided within the drive circuit DRC.

The gate driver GD, the source driver SD, and the common electrode driver circuit CD are arranged on a flexible substrate connected to a peripheral area (frame area) around the display section or the display panel PNL. A gate driver GD sequentially applies an ON voltage to a plurality of gate lines G, and supplies the ON voltage to gate electrodes of pixel switches SW electrically connected to the selected gate line G. FIG. Conduction is established between the source electrode and the drain electrode of the pixel switch SW whose gate electrode is supplied with ON voltage. The source driver SD supplies output signals corresponding to the plurality of source lines S, respectively. A signal supplied to the source line S is supplied to the corresponding pixel electrode PE through the pixel switch SW that conducts between the source electrode and the drain electrode.

The operations of the gate driver GD, the source driver SD, and the common electrode drive circuit CD are controlled by a control circuit CTR arranged outside or inside the display panel PNL. Furthermore, the control circuit CTR controls the operation of the backlight BLT.

FIG. 2 is a cross-sectional view showing the structure of the sensor-equipped display device DSP of the embodiment.

The sensor-equipped display device DSP has an in-cell touch sensor, and includes a display panel PNL, a backlight BLT, a first optical element OD1 and a second optical element OD2. In the illustrated example, the display panel PNL is a liquid crystal display panel, but it may be another flat panel such as an organic electroluminescence display panel or micro (μ) LED. Further, the illustrated display panel PNL has a configuration corresponding to the horizontal electric field mode as a display mode, but may have a configuration corresponding to other display modes.

The display panel PNL includes a first substrate SUB1, a second substrate SUB2, and a liquid crystal layer LQ. The first substrate SUB1 and the second substrate SUB2 are bonded together with a predetermined cell gap formed therebetween. The liquid crystal layer LQ is held in a cell gap between the first substrate SUB1 and the second substrate SUB2. It can also be said that the first substrate SUB1 is an array substrate and the second substrate SUB2 is a counter substrate.

The first substrate SUB1 is formed using a first insulating substrate 10 having optical transparency such as a glass substrate or a resin substrate. The first substrate SUB1 includes source lines S, a common electrode COME, pixel electrodes PE, a first insulating film 11, a second insulating film 12, and a third insulating film on the side of the second insulating substrate 20 facing the second substrate SUB2. 13, a first alignment film AL1, and the like.

Here, the pixel electrode PE and the common electrode COME form a display pixel together with a pixel region of the liquid crystal layer arranged between these electrodes, and the display pixels are arranged in a matrix on the display panel PNL.

The first insulating film 11 is arranged on the first insulating substrate 10 . Although not described in detail, between the first insulating substrate 10 and the first insulating film 11, gate lines G, gate electrodes of switching elements, semiconductor layers, and the like are arranged. A source line S is formed on the first insulating film 11 . Source electrodes and drain electrodes of switching elements are also formed on the first insulating film 11 . In the illustrated example, the source line S extends in the second direction Y in parallel with the common electrode COME.

The second insulating film 12 is arranged on the source line S and the first insulating film 11 . A common electrode COME is formed on the second insulating film 12 . In the illustrated example, the common electrode COME is composed of a plurality of segments. Each segment of the common electrode COME extends in the second direction Y and is arranged in the first direction X at intervals. Such a common electrode COME is made of a transparent conductive material such as indium tin oxide (ITO) or indium zinc oxide (IZO). In the illustrated example, the metal layer ML is formed on the common electrode COME to reduce the resistance of the common electrode COME, but the metal layer ML may be omitted.

The third insulating film 13 is arranged on the common electrode COME, the metal layer ML, and the second insulating film 12 . A pixel electrode PE is formed on the third insulating film 13 . Each pixel electrode PE is positioned between adjacent source lines S and faces the common electrode COME. Each pixel electrode PE has a slit SL at a position facing the common electrode COME. Such pixel electrodes PE are made of, for example, a transparent conductive material such as ITO or IZO. The first alignment film AL1 covers the pixel electrode PE and the third insulating film 13 .

On the other hand, the second substrate SUB2 is formed using a second insulating substrate 20 having optical transparency such as a glass substrate or a resin substrate. The second substrate SUB2 includes a black matrix BM, color filters CFR, CFG, CFB, an overcoat layer OC, a second alignment film AL2, etc. on the side of the first insulating substrate 10 facing the first substrate SUB1.

A black matrix BM is formed on the inner surface of the second insulating substrate 20 to partition each pixel. Color filters CFR, CFG, and CFB are formed on the inner surface of the second insulating substrate 20, and partially overlap the black matrix BM. The color filter CFR is, for example, a red color filter, the color filter CFG is, for example, a green color filter, and the color filter CFB is, for example, a blue color filter. An overcoat layer OC covers the color filters CFR, CFG, and CFB. The overcoat layer OC is made of a transparent resin material. The second alignment film AL2 covers the overcoat layer OC.

The detection electrodes DETE are formed on the outer surface of the second insulating substrate 20 . The detection electrode DETE extends in a direction intersecting each segment of the common electrode COME, and extends in the first direction X in the illustrated example. Such detection electrodes DETE are made of, for example, a transparent conductive material such as ITO or IZO.

The backlight BLT is arranged on the back side of the display panel PNL. Various forms can be applied as the backlight BLT, and any of those using light emitting diodes (LEDs) and cold cathode fluorescent lamps (CCFLs) as light sources can be applied.

The first optical element OD1 is arranged between the first insulating substrate 10 and the backlight BLT. The second optical element OD2 is arranged above the detection electrode DETE. Each of the first optical element OD1 and the second optical element OD2 includes at least a polarizing plate, and may include a retardation plate if necessary.

Next, a touch sensor used in the sensor-equipped display device DSP will be described. As a method for detecting that an external proximity object such as a user's finger or a pen is in contact with the touch panel as described above, or is in proximity to the touch panel, there are a mutual detection method and a self detection method. There is a method.

<Mutual detection method>
FIG. 3A is a diagram showing a typical basic configuration of the mutual detection method of the sensor-equipped display device DSP according to the embodiment. Common electrodes COME (Tx) and detection electrodes DETE (Rx) are used as sensors.

The common electrode COME (Tx) includes a plurality of common electrodes Come1, Come2, Come3, . The plurality of common electrodes Come1, Come2, Come3, . . . are, for example, striped. The plurality of common electrodes Come1, Come2, Come3, . . . are arranged in the scanning (driving) direction (Y direction or X direction).

On the other hand, the detection electrodes DETE (Rx) include a plurality of detection electrodes Dete1, Dete2, Dete3, . . . (thinner than the common electrode). The plurality of detection electrodes Dete1, Dete2, Dete3, . . . are, for example, striped. The plurality of detection electrodes Dete1, Dete2, Dete3, .

The common electrode COME and the detection electrode DETE are spaced apart. Therefore, between the plurality of common electrodes Come1, Come2, Come3, . . . and the plurality of detection electrodes Dete1, Dete2, Dete3, . exist.

A predetermined voltage is commonly applied to the plurality of common electrodes (Come) during an image display period (display period), and a pulsed drive pulse is applied during a touch detection period (detection period). Therefore, in the detection period, the common electrode (Come) can also be called the drive electrode (Tx).

A plurality of common electrodes Come1, Come2, Come3, . It is now assumed that the user's finger is present in the vicinity of the intersection of the detection electrode Dete2 and the drive electrode Tx2. At this time, when a drive pulse (Sig) is supplied to the drive electrode Tx2, a pulse-like waveform is obtained at the detection electrodes Rx (Dete1, Dete2, Dete3, . A pulse is obtained that has a lower amplitude level than the pulse obtained from the sensing electrode. The detection electrodes Rx (Dete1, Dete2, Dete3, . . . ) monitor fringe electric fields from the drive electrodes Tx (Come1, Come2, Come3, . . . ). There is an effect of shielding this fringe electric field. Shielding of the fringe electric field reduces the detection potential of the detection electrode Rx.

In mutual detection, this detection potential difference can be treated as a position DETP detection pulse. The illustrated capacitance Cc differs depending on whether the user's finger is closer to or farther from the detection electrode DETE. For this reason, the level of the detection pulse also differs depending on whether the user's finger is close to the detection electrode DETE or far from it. Therefore, the proximity of the finger to the plane of the touch panel can be determined by the amplitude level of the detection pulse. The two-dimensional position of the finger on the plane of the touch panel can be detected by the electrode driving timing by the driving pulse Sig and the output timing of the detection pulse.

<Self detection method>
FIG. 3B is a diagram showing a typical basic configuration of the self-detection method according to the embodiment. In the self-detection method, pulse-shaped self-detection drive pulses are sequentially supplied to the detection electrodes DETE (Rx) and the common electrode COME (Tx) to detect the position and coordinates of the user's finger, which is an external proximity object. do. FIG. 3B exemplarily shows the detection electrode Dete2 (Rx2) and the common electrode Come2 (Tx2). It shows a case where the finger O1 is approaching or in contact. User's finger O1 causes the capacitance of detection electrode Dete2 (Rx2) to increase to the sum of the self-capacitance of Dete2 (Rx2) and the capacitance Cx1 of user's finger O1. Similarly, the capacitance of the common electrode Come2 (Tx2) increases to the sum of the self-capacitance of the common electrode Come2 (Tx2) and the capacitance Cx2 of the user's finger O1. In this state, for example, first, the detection electrode Dete2 (Rx2) is driven by the self-detection drive pulse Sig1 through the resistor R1, and the increased electrostatic capacitance of the detection electrode Dete2 (Rx2) increases with the self-detection drive pulse. Charged by Sig1. The detection circuit DET1 detects that the user's finger O1 is present on the detection electrode Dete2 (Rx2) based on the value of the charging voltage changed by the capacitor Cx1. Next, the common electrode Come2 (Tx2) is driven by the self-detection drive pulse Sig2 via the resistor R2, and the increased electrostatic capacitance of the common electrode Come2 (Tx2) is charged by the self-detection drive pulse Sig2. The common electrode Come2 (Tx2) detects that the user's finger O1 is near the common electrode Come2 (Tx2) based on the value of the charging voltage changed by the capacitor Cx2. As a result, it is detected that the user's finger O1 is at the intersection of the detection electrode Dete2 (Rx2) and the common electrode Come2 (Tx2), and the position and coordinates of the user's finger O1 on the plane of the touch panel are detected.

Although not shown in FIG. 3B, the common electrode COME (Tx) and the detection electrode DETE (Rx) are used as sensors, as in FIG. 3A. The common electrodes COME, which are sequentially driven (scanned) by the self-detection drive pulse Sig2, are composed of a plurality of striped common electrodes Come1 (Tx1), Come2 (TX2), Come3 (Tx3), . . . including. The plurality of common electrodes Come1 (Tx1), Come2 (Tx2), Come3 (Tx3), . . . are arranged in the Y direction or the X direction. Similarly, the detection electrodes DETE sequentially driven (scanned) by the self-detection driving pulse Sig1 are composed of a plurality of striped detection electrodes Dete1 (Rx1), Dete2 (Rx2), Dete3 (Rx3), . , which is thinner than the striped common electrode), similar to FIG. 3A. The plurality of detection electrodes Dete1 (Rx1), Dete2 (Rx2), Dete3 (Rx3), ... are orthogonal to the plurality of common electrodes Come1 (Tx1), Come2 (Tx2), Come3 (Tx3) ... Alternatively, they are arranged in a crossing direction (X direction or Y direction). Using the configuration as shown in FIG. 3B, a plurality of detection electrodes Dete1 (Rx1), Dete2 (Rx2), Dete3 (Rx3), . By sequentially driving (scanning) both of Come3 (Tx3) . The position of the external proximity object O1 at the intersection of the common electrodes Come1 (Tx1), Come2 (Tx2), Come3 (Tx3), . . . can be detected. In the detection period in the self-detection method, the plurality of detection electrodes Dete1 (Rx1), Dete2 (Rx2), Dete3 (Rx3), ... and the plurality of common electrodes Come1 (Tx1), Come2 (Tx2), Come3 ( Tx3) . . . can be regarded as detection electrodes.

Further, in such a self-detection method, only the detection electrodes Dete1 (Rx1), Dete2 (Rx2), Dete3 (Rx3), . Alternatively, only the presence or absence of an external proximity object such as a finger may be detected, and the coordinates of the external proximity object may be detected by switching to mutual detection.

Although not shown in FIGS. 3A and 3B, a switch or the like may be used to switch between the Mutual detection method and the Self detection method. Also, the configuration of the self-detection method shown in FIG. 3B is an example, and the present invention is not limited to this.

4A and 4B are diagrams for explaining driving methods of the mutual detection method and the self-detection method of the sensor-equipped display device DSP according to the embodiment. As described above, since the common electrode COME used for image display is also used as an electrode for touch position detection, the image display operation and the touch position detection operation are driven in a time-sharing manner.

In the mutual detection method shown in FIG. 4A, a period for displaying an image and a period for detecting a touch position are divided, and the divided image display period and the divided touch position detection period are alternately repeated to display one frame. configure a period; That is, after executing the operation of outputting the video signal (SIGn) for each color corresponding to the signal (SELR/G/B) for selecting the three colors of RGB for a plurality of divided display rows, , the mutual detection operation is performed by inputting the drive pulse Sig to the drive electrodes Tx. Then, this operation is sequentially repeated for the plurality of divided display rows and the plurality of drive electrodes Tx. In this example, two frames of touch detection are performed during one frame display period. During the touch detection period of one frame, the drive electrodes Tx1, Tx2, Tx3, .

In the self-detection method shown in FIG. 4B, after displaying one frame of video, a self-detection drive pulse (Sig1) is input to all the detection electrodes DETE to perform the self-detection operation. That is, after executing the operation of outputting the video signal (SIGn) for each color in response to the signal (SELR/G/B) for selecting the three colors of RGB for all display rows, all the detection electrodes DETE are subjected to self detection. A drive pulse for detection (Sig1) is input to execute the self-detection operation. All the detection electrodes DETE (Rx) are scanned with the self-detection drive pulse (Sig1), and then all the common electrodes COME (Tx) are scanned with the self-detection drive pulse (Sig2) to perform the self-detection operation. may The reason why the sensing operation is collectively performed without division in the self-detection method is that the sensing sensitivity can be increased by collectively obtaining the sensing data. The self-detection method is a method capable of sensing with higher sensitivity than the mutual detection method. Further, the method is not limited to the method of FIG. 4B, and self-sensing may be performed during the detection period shown in FIG. 4A (divided method).

Next, the configuration of the display device according to the embodiment will be described with reference to the drawings. In the following description, a plurality of common electrodes Come1, Come2, Come3, . Also, the plurality of detection electrodes Dete1, Dete2, Dete3, .

FIG. 5 is a diagram illustrating a schematic configuration of the display device according to the embodiment.

The display device DSP includes a display panel PNL, a flexible printed circuit board FPC1, a flexible printed circuit board FPC2, and an IC chip1. The display panel PNL is a liquid crystal display panel, and includes a first substrate (also called TFT substrate or array substrate) SUB1 and a second substrate (also called counter substrate) SUB2. The flexible printed circuit board FPC1 and the flexible printed circuit board FPC2 are also called flexible circuit board FPC1 (first flexible circuit board) and flexible circuit board FPC2 (second flexible circuit board).

The display panel PNL includes a display portion (display area) DA for displaying an image, and a frame-shaped non-display portion (non-display area) NDA surrounding the outer circumference of the display portion DA. A plurality of display pixels PX are arranged in a matrix in the display section (display area) DA.

The second substrate SUB2 faces the first substrate SUB1. The first substrate SUB1 has a mounting portion extending in the Y direction more than the second substrate SUB2. A plurality of external terminals are formed on the mounting portion. A flexible printed circuit board FPC1 is connected to a plurality of external terminals of the mounting portion.

The IC chip 1 is mounted on a flexible printed circuit board FPC1 in this example. The IC chip 1 may be mounted on the mounting portion of the first substrate SUB1. In that case, the flexible printed circuit board FPC1 may be omitted and the flexible printed circuit board FPC2 may be connected to the mounting portion of the first substrate SUB1. The IC chip 1 incorporates a display driver DD that outputs signals necessary for image display in a display mode for displaying an image. In the illustrated example, the IC chip 1 incorporates a touch detection controller TC that controls a touch sensing mode for detecting the approach or contact of an object to the display device DSP. The display driver DD section and the touch detection control section TC may be separate IC chips. When the display driver DD section and the touch detection control section TC are formed as separate IC chips, the touch detection control section TC may be provided on the flexible printed circuit board FPC1 or on the flexible printed circuit board FPC2. The flexible printed circuit board FPC2 is connected to the second board SUB2 and the flexible printed circuit board FPC1. The flexible printed circuit board FPC2 has a portion provided above the flexible printed circuit board FPC1.

Although omitted in FIG. 5 and other drawings for the sake of simplification, the wiring of each substrate is connected to the terminal portion provided on each substrate, and the terminal portion of one substrate and the terminal of the other substrate are connected to each other. Wiring between the substrates is connected by electrically connecting the portions.

FIG. 6 is a diagram for explaining the touch detection function of the display device according to the embodiment. 7 is a diagram showing a partially enlarged view of FIG. 6. FIG. FIG. 6 exemplarily shows a display device DSP having seven drive electrodes Tx1 to Tx7 and five touch detection electrodes Rx1 to Rx5 in the mutual detection method. 6 and 7, for the sake of simplification of the drawings, only one lead wire 2 is drawn, but in practice, the same number as the touch detection electrodes Rx1, Rx2, Rx3, . . . is provided. In the case of the self (Self) detection method, the drive electrodes Tx1 to Tx7 and the five touch detection electrodes Rx1 to Rx5 are regarded as touch detection electrodes.

6 and 7, the display area DA of the display device DSP includes a plurality of drive electrodes Tx1, Tx2, Tx3, . . . extending in the X direction, and a plurality of touch electrodes extending in the Y direction. Detecting electrodes Rx1, Rx2, Rx3, . . . are provided. Therefore, the display area DA can also be called a touch detection area. Each of the plurality of touch detection electrodes Rx1, Rx2, Rx3, . The lead wiring 2 is arranged on the second substrate SUB2, the flexible printed circuit board FPC2, and the flexible printed circuit board FPC1, and is connected to the touch detection control section TC of the IC chip 1. FIG. A first detection wiring 3 for detecting noise and capacitance variation is arranged in parallel with or adjacent to the lead wiring 2 . The first detection wiring 3 is connected to the touch detection control section TC of the IC chip 1 in the same manner as the lead wiring 2 . The first detection wiring 3 is driven by a self-detection method by the touch detection controller TC. Further, when the signal that becomes the noise source is the signal of the drive electrodes Tx1 to Tx7 or other AC signal, it is also possible to perform detection by performing a mutual detection method using this signal and the first detection wiring 3. . This makes it possible to detect noise and capacitance variation.

Distortion of the cover glass on the display panel DSP when the screen is touched, interference between the display panel DSP and a set housing such as a mobile phone, or bending parts such as flexible printed circuit boards FPC1 and FPC2 and other parts, A change in the distance (interference with a conductive object) between the wiring NOS, which is a noise source on the flexible printed circuit board FPC1, and the lead wiring 2 on the flexible printed circuit board FPC2 causes a change in the capacitance of the lead wiring 2. False touch recognition (touch ghost) may occur. In the present embodiment, by providing the first detection wiring 3, it is possible to detect capacitance value fluctuations other than the display area (touch detection area) DA of the touch sensor, thereby avoiding erroneous touch recognition.

Next, an arrangement example of the first detection wiring will be described. FIG. 8A is a diagram showing an arrangement example 1 of the extraction wiring 2 and the first detection wiring 3. FIG. FIG. 8B is a diagram showing an arrangement example 2 of the lead wiring 2 and the first detection wiring 3. As shown in FIG. 8A and 8B exemplarily show a state in which each of the touch detection electrodes Rx1 to Rx5 is connected to one lead wire 2. FIG. In addition, in FIGS. 8A and 8B, other lead wires 2 that are not connected to the touch detection electrodes Rx1 to Rx5 are similarly connected to the touch detection electrodes Rx (not shown).

As shown in FIG. 8A, arrangement example 1 is an arrangement example in which each of the plurality of lead wires 2 is sandwiched between two of the plurality of first detection wires 3 in the flexible printed circuit board FPC2. That is, one of the plurality of first detection wirings 3 is arranged next to each of the plurality of lead wirings 2 . In this case, the detection sensitivity of capacitance variation can be increased. However, since the total number of lead wires 2 and first detection wires 3 is large, it is necessary to ensure a wide wiring area in the flexible printed circuit board FPC2.

As shown in FIG. 8B, arrangement example 2 is an arrangement example in which a plurality of lead wires 2 are sandwiched between two first detection wires 3 in a flexible printed circuit board FPC2. That is, the first detection wirings 3 are arranged on the left and right sides of the plurality of lead wirings 2 . In this case, the detection sensitivity of capacitance variation is slightly lower than the detection sensitivity of FIG. 8A. However, since it can be shared with the guard wiring described in FIG. 9, it is possible to reduce the increase in wiring in the flexible printed circuit board FPC2. The first detection wiring 3 is not limited to be arranged adjacent to all the lead wirings 2, and one first detection wiring may be arranged adjacent to every predetermined number of lead wirings.

FIG. 9 is a diagram illustrating another schematic configuration of the display device according to the embodiment. 9 is different from FIG. 6 in that the shield wiring SHL is provided so as to surround the touch detection electrodes Rx1 to Rx5 and that the shield wiring SHL is connected to the first detection wiring 3. be. Other configurations are the same as in FIG.

The shield wiring SHL is provided in the non-display area NDA, and is provided in a ring shape so as to surround the display area DA in which the drive electrodes Tx1 to Tx7 and the touch detection electrodes Rx1 to Rx5 are formed. there is The shield wiring SHL can also be called a guard ring wiring or a shield ring wiring. Also, the shield wiring may be cut in the middle instead of being circular (ring-shaped).

Next, a detection method using the first detection wiring 3 and the shield wiring SHL will be described with reference to FIGS. 10A to 10C.

10A to 10C are circuit diagrams showing detection methods using the first detection wiring 3 and the shield wiring SHL. FIG. 10A is a circuit diagram showing a detection method when the first detection wiring 3 and the shield wiring SHL are set at a fixed potential (reference potential). FIG. 10B is a circuit diagram showing a detection method when the first detection wiring 3 and the shield wiring SHL are driven by signals having the same phase as the detection electrodes Rx (active guard driving). FIG. 10C is a circuit diagram showing a detection method when the first detection wiring 3 and the shield wiring SHL are driven by a self-detection circuit.

As shown in FIG. 10A, the touch detection controller TC has two resistive elements R11 and R12 and a detection circuit DTEC1. Two resistance elements R11 and R12 are connected in series between a first reference potential VDD such as a power supply potential and a second reference potential GND different from the first reference potential VDD such as a ground potential. An input of the detection circuit DTEC1 is connected to a common connection point between the resistance element R11 and the resistance element R12. The shield wiring SHL is connected via the first detection wiring 3 to a common connection point between the resistive element R11 and the resistive element R12. The detection circuit DTEC1 can use, for example, an amplifier circuit such as a voltage follower circuit.

As a result, the shield line SHL and the first detection line 3 are supplied with the reference potential obtained by dividing the voltage difference between the first reference potential VDD and the second reference potential GND by the resistance elements R11 and R12. Therefore, when the potential of the shield wiring SHL or the first detection wiring 3 fluctuates due to noise or the like, the output potential of the detection circuit DTEC1 fluctuates, so that the touch detection controller TC can detect noise.

As shown in FIG. 10B, the touch detection controller TC has a drive signal source SIGS1, two resistance elements R21 and R22, and a detection circuit DTEC2. Two resistance elements R21 and R22 are connected in series between the output of the driving signal source SIGS1 and the second reference potential GND. An input of the detection circuit DTEC2 is connected to a common connection point between the resistance element R21 and the resistance element R22. The shield wiring SHL is connected via the first detection wiring 3 to a common connection point between the resistive element R21 and the resistive element R22. The detection circuit DTEC2 can use, for example, an amplifier circuit such as a voltage follower circuit.

As a result, the shield wiring SHL and the first detection wiring 3 are driven by the drive signal having the same phase as the detection electrode Rx from the drive signal source SIGS1. Therefore, when the shield wiring SHL or the first detection wiring 3 is affected by noise or the like, the output potential of the detection circuit DTEC2 fluctuates, so that the touch detection control unit TC can detect noise. If the shield wiring SHL is not provided, a drive signal having the same phase as that of the detection electrodes Rx is input to the first detection wiring 3 . It is desirable that the signal to be driven as the active guard should be driven not only in phase with the detection electrode Rx but also with substantially the same amplitude.

As shown in FIG. 10C, the touch detection controller TC has a drive signal source SIGS2, a capacitive element 31, two resistive elements R31 and R32, and a detection circuit DTEC3. Two resistance elements R31 and R32 are connected in series between the first reference potential VDD and the second reference potential GND. The output of the driving signal source SIGS2 is connected via the capacitive element C31 to the common connection point between the resistive elements R31 and R32. An input of the detection circuit DTEC3 is connected to a common connection point between the resistance element R31 and the resistance element R32. The shield wiring SHL is connected via the first detection wiring 3 to a common connection point between the resistive element R31 and the resistive element R32.

As a result, the shield wiring SHL and the first detection wiring 3 are driven by the self-detection driving pulse from the driving signal source SIGS2. Noise detection and capacitance variation detection in the wiring 3 can be performed. Also in this case, when the shield wiring SHL is not provided, the drive signal having the same phase as that of the detection electrode Rx is input to the first detection wiring 3 . It is desirable that the signal to be driven as the active guard should be driven not only in phase with the detection electrode Rx but also with substantially the same amplitude.

11A and 11B are diagrams conceptually showing the relationship between the first detection wiring and the noise source. As shown in FIG. 11A, the wiring NOS that becomes a noise source is provided on the flexible printed circuit board FPC1, and the first detection wiring 3 is provided on the flexible printed circuit board FPC2. Let d be the distance between the first detection wiring 3 and the wiring NOS. For example, when the flexible printed circuit board FPC2 is pushed downward, the distance between the first detection wiring 3 and the wiring NOS becomes shorter than the distance d. Therefore, the parasitic capacitance between the first detection wiring 3 and the wiring NOS changes with respect to the parasitic capacitance in the case of the distance d between the first detection wiring 3 and the wiring NOS. This change in parasitic capacitance is detected by the touch detection control unit TC using the first detection wiring 3 to avoid erroneous touch recognition. As shown in FIG. 11B, the wiring NOS that becomes a noise source may be provided not only on the flexible printed circuit board FPC1 but also on the first substrate SUB1 that overlaps the flexible printed circuit board FPC2.

FIG. 12 is a diagram showing a first touch coordinate detection method according to the embodiment. The first touch coordinate detection method has the following steps during the touch position detection period. As for the detection method, either the mutual detection method or the self detection method may be used.

Step S1: The touch detection controller TC drives the touch sensors using the drive electrodes Tx1, Tx2, Tx3, . . . and the touch detection electrodes Rx1, Rx2, Rx3, .

Step S2: A touch is detected by the touch detection controller TC. In the case of the mutual detection method, the touch detection control unit TC obtains detection values based on pulse waveforms obtained from the touch detection electrodes Rx1, Rx2, Rx3, . Detect touch. Further, in the case of the self-detection method, the touch detection control unit TC detects based on the charged voltage values of the drive electrodes Tx1, Tx2, Tx3, ... and the touch detection electrodes Rx1, Rx2, Rx3, ... A touch on the touch detection area of the touch panel is detected by obtaining the value. Also, a reaction such as a potential change of the first detection wiring 3 is detected by the touch detection control unit TC.

When the plane of the touch panel is touched, in many cases, the potential fluctuation of the first detection wiring 3 does not occur. On the other hand, as described with reference to FIGS. 11A and 11B, when the distance d between the first detection wiring 3 and the wiring NOS serving as a noise source changes due to a pressing force or the like applied to the display device from the outside, the first A reaction such as a potential change appears in the first detection wiring 3 based on the change in the value of the parasitic capacitance between the detection wiring 3 and the wiring NOS that is a noise source. In this case, the potential of the lead wires 2 connected to the drive electrodes Tx1, Tx2, Tx3, . . . and the touch detection electrodes Rx1, Rx2, Rx3, . A similar reaction may occur. In addition, there is a case where the potential of the lead-out wiring 2 is unreacted.

Step S3: It is determined by the touch detection control unit TC whether or not there is a reaction such as a potential change of the first detection wiring 3 . If the first detection wiring 3 reacts such as potential fluctuation (Yes), the process proceeds to step S4. On the other hand, if the first detection wiring 3 does not respond to changes in potential (No), the process proceeds to step 5 . If the fluctuation width of the potential of the first detection wiring 3 is equal to or greater than a predetermined threshold value, it is determined that there is a reaction, and if it is equal to or less than the predetermined threshold value, it is determined that there is no reaction.

Step S4: Detection of touch coordinates is stopped. After that, the process proceeds to step S1 in order to perform the next touch position detection period.

Step S5: Touch coordinates are detected. After that, the process proceeds to step S1 in order to perform the next touch position detection period.

According to the first touch coordinate detection method, as described with reference to FIGS. 11A and 11B, when the distance d between the first detection wiring 3 and the wiring NOS serving as a noise source changes, step S4 indicates to stop detecting touch coordinates. Therefore, recognition of an erroneous touch by the touch detection control unit TC can be avoided.

FIG. 13 is a diagram showing a second touch coordinate detection method according to the embodiment. 13 differs from the first touch coordinate detection method shown in FIG. 12 in step S41 shown in FIG. Other steps S1, S2, S3 and S5 are the same as those in FIG. 12, so description thereof is omitted.

In step S41, the "detection value from the first detection wiring 3" is subtracted from the "detection value from the touch detection electrodes Rx (Rx1, Rx2, Rx3, . . . )" ((detection value from the touch detection electrodes Rx). - (detection value from the first detection wiring 3)) is performed by the touch detection control unit TC. That is, the capacitance variation of the first detection wiring 3 generated based on the change in the value of the parasitic capacitance between the first detection wiring 3 and the noise source wiring NOS is regarded as a capacitance offset, and touch detection is performed. A capacitance offset is added to the detection values from the electrodes Rx1, Rx2, Rx3, . . .

As shown in FIG. 13, touch coordinates are detected based on the calculation result in step S41 (step S5).

According to the second touch coordinate detection method, as described with reference to FIGS. 11A and 11B, when the distance d between the first detection wiring 3 and the wiring NOS serving as a noise source changes, in step S41 Since touch coordinates are detected based on the calculation result, accurate touch coordinates are detected by the touch detection control unit TC. Therefore, erroneous touch recognition can be avoided.

14A to 14D are cross-sectional views showing first to fourth states of Arrangement Example 1 shown in FIG. 8A. 14A and 14B show the case where the distance between the flexible printed circuit board FPC1 and the flexible printed circuit board FPC2 is relatively long. On the other hand, FIGS. 14C and 14D show a state in which the distance between the flexible printed circuit board FPC1 and the flexible printed circuit board FPC2 is narrowed compared to FIGS. 14A and 14B. Also, FIGS. 14A and 14C show a state where the wiring NOS, which is a noise source, is arranged near the left end of the flexible printed circuit board FPC1. On the other hand, FIGS. 14B and 14D show a state in which the wiring NOS, which is a noise source, is arranged in the central portion of the flexible printed circuit board FPC1.

In FIGS. 14A and 14B, since the wiring NOS that is a noise source is far from the plurality of lead wirings 2 and the plurality of first detection wirings 3 arranged on the flexible printed circuit board FPC2, the plurality of lead wirings 2 and the plurality of first detection wirings 3 are far from each other. There is no influence of noise on the first detection wiring 3 of .

14C and 14D, since one of the plurality of first detection wirings 3 is arranged next to each of the plurality of lead wirings 2, the influence of noise on each of the plurality of lead wirings 2 is 1 can be detected by the detection wiring 3 . Therefore, the touch detection control unit TC can perform accurate touch coordinate detection using step S41 of the second touch coordinate detection method described with reference to FIG. 13 . Alternatively, step S4 described in FIG. 12 may be used to stop detecting touch coordinates.

15A to 15D are cross-sectional views showing first to fourth states of Arrangement Example 2 shown in FIG. 8B. 15A and 15B show the case where the distance between the flexible printed circuit board FPC1 and the flexible printed circuit board FPC2 is relatively long. On the other hand, FIGS. 15C and 15D show a state in which the distance between the flexible printed circuit board FPC1 and the flexible printed circuit board FPC2 is narrowed compared to FIGS. 15A and 15B. Also, FIGS. 15A and 15C show a state in which the wiring NOS, which is a noise source, is arranged near the left end of the flexible printed circuit board FPC1. On the other hand, FIGS. 15B and 15D show a state in which the wiring NOS, which is a noise source, is arranged in the central portion of the flexible printed circuit board FPC1. 15B and 15D, two second detection wirings 31 are provided at positions of the flexible printed circuit board FPC1 facing the two first detection wirings 3 provided on the flexible printed circuit board FPC2. there is For example, the second reference potential GND is supplied to the two second detection wirings 31 .

In FIG. 15A, since the wiring NOS that is a noise source is far from the plurality of lead wirings 2 and the two first detection wirings 3 arranged on the flexible printed circuit board FPC2, the plurality of lead wirings 2 and the two first detection wirings 3 The first detection wiring 3 is not affected by noise.

In FIG. 15C, noise affects the extraction wiring 2 and the first detection wiring 3 arranged on the left side. The touch detection control unit TC can determine that there is a capacitance change in the lead-out wiring 2 and the first detection wiring 3 from the detection values of the lead-out wiring 2 and the first detection wiring 3, and also recognizes that there is a reaction outside the display area DA. can. Therefore, the touch detection control unit TC can stop coordinate detection using step S4 of the first touch coordinate detection method described with reference to FIG.

However, in FIG. 15C, when the first detection wiring 3 is far from the noise source wiring NOS (when the wiring NOS is near the center of the flexible printed circuit board FPC1), the capacitance fluctuation in the first detection wiring 3 becomes small. , the noise detection sensitivity drops. In that case, as shown in FIGS. 15B and 15D, it is preferable to provide two second detection wirings 31 on the flexible printed circuit board FPC1.

In FIG. 15B, since the wiring NOS that is a noise source is far from the plurality of lead wirings 2 and the two first detection wirings 3 arranged on the flexible printed circuit board FPC2, the plurality of lead wirings 2 and the two first detection wirings 3 are far. The first detection wiring 3 is not affected by noise.

In FIG. 15D, a plurality of lead wirings 2 facing the wiring NOS, which is a noise source, is affected by the noise source and causes a change in capacitance. Since the two first detection wirings 3 are separated from the wiring NOS which is a noise source, they are not affected by the noise source. However, when the first detection wiring 3 and the second detection wiring 31 provided facing the first detection wiring 3 approach each other, a capacitance change occurs between the first detection wiring 3 and the second detection wiring 31. . At that time, if the lead wire 2 is affected by a noise source, coordinate detection can be stopped using step S4 of the first touch coordinate detection method described with reference to FIG. Alternatively, if the capacitance between the first detection wiring 3 and the second detection wiring 31 is equal to or greater than a predetermined value, it is determined that the flexible printed circuit board FPC1 and the flexible printed circuit board FPC2 are close enough to be affected by the noise source. to stop coordinate detection.

The first detection wiring 3 can detect the capacitance value between the first detection wiring 3 and the second detection wiring 31 by driving the first detection wiring 3 with a drive pulse based on the self-detection method. Alternatively, mutual detection may be performed by using one of the first detection wiring 3 and the second detection wiring 31 as the drive electrode (Tx) and the other as the detection electrode (Rx). For example, the second detection wiring 31 is used as the drive electrode (Tx), and the first detection wiring 3 is used as the detection electrode (Rx). In this case, the drive electrodes (Tx) and the detection electrodes (Rx) are connected to the touch detection control unit, and the touch detection control unit applies an AC voltage to the wires that become the drive electrodes (Tx), which become the detection electrodes (Rx). Detect wiring variations.

If the wiring on the flexible printed circuit board FPC1 that becomes a noise source is known in advance, a first line is placed on the flexible printed circuit board FPC2 at a position corresponding to the wiring that becomes a noise source on the flexible printed circuit board FPC1. A detection wiring may be arranged. In this case, the first detection wirings 3 may be arranged at positions corresponding to all noise source wirings, or the first detection wirings 3 may be arranged only at positions corresponding to noise source wirings having a relatively large influence. may be placed.

FIG. 16 is a diagram illustrating another schematic configuration of the display device according to the embodiment. FIG. 16 shows an on-cell type display device DSP with a touch panel. Note that the on-cell method is a method in which the touch panel TPNL is mounted on the display panel PNL. The touch panel TPNL is provided with drive electrodes Tx1 to Tx7, touch detection electrodes Rx1 to Rx5, and shield wiring SHL. 16 differs from FIG. 9 in that the flexible printed circuit board FPC2 in FIG. The point is that the detection control unit TC is mounted on the flexible printed circuit board FPC3 in the form of an IC chip. With this change, the flexible circuit board FPC3 is connected to the touch panel TPNL. Further, the lead wiring 2 and the first detection wiring 3 are provided on the flexible printed circuit board FPC3 and connected to the touch detection controller TC. Other configurations are the same as in FIG. The IC chip 1 (DD) may be mounted on the mounting portion of the first substrate SUB1.

In FIG. 16, the bending part BP exemplarily shows the part where the flexible printed circuit boards FPC1 and FPC3 are bent. As a result, the IC chip 1 and the touch detection control unit TC can be arranged on the back side of the backlight BLT, so that various devices in which the display device DSP is mounted can be miniaturized.

17 is a sectional view conceptually showing a state in which the flexible printed circuit board of the display device shown in FIG. 16 is bent.

As shown in FIG. 17, the display device DSP has a backlight BLT, a display panel PNL, a touch panel TPNL, a polarizing plate POL, and a cover glass CG. The back surface of the backlight BLT is connected to the second reference potential GND, and the display panel PNL, the touch panel TPNL, the polarizing plate POL and the cover glass CG are mounted in this order on the upper side of the backlight BLT. A flexible printed circuit board FPC3 provided with the first detection wiring 3 is connected to the touch panel TPNL. A touch detection controller TC is mounted on the flexible printed circuit board FPC3, and the touch detection controller TC is connected to the first detection wiring 3. As shown in FIG. The flexible printed circuit board FPC3 is bent, and the touch detection controller TC is arranged on the back side of the backlight BLT.

According to the present embodiment, even when the flexible printed circuit board FPC3 is bent, the first detection wiring 3 can detect the influence of noise and the change in capacitance due to the variation in the space interval d1 in the bent portion and other portions. It is possible.

FIG. 18 is a diagram showing another arrangement example of the lead wiring and the first detection wiring.

A plurality of lead wires 2 and a plurality of first detection wires 3 are arranged on the flexible printed circuit board FPC3 in the same manner as in arrangement example 2 of FIG. 8B. Each of the plurality of lead wirings 2 is connected to the touch detection control section TC. On the other hand, the plurality of first detection wirings 3 are combined into one first detection wiring 3G in the vicinity of the touch detection controller TC, and only the first detection wiring 3G is connected to the touch detection controller TC. According to such an arrangement example, the number of terminals of the touch detection control unit TC can be reduced.

FIG. 19 is a diagram illustrating another schematic configuration of the display device according to the embodiment; 19 differs from FIG. 9 in that two pairs of first detection wiring 3a and lead wiring 2a and one pair of first detection wiring 3b and lead wiring 2b are provided on the flexible printed circuit board FPC1. The point is that Two pairs of first detection wiring 3a and lead wiring 2a and one pair of first detection wiring 3b and lead wiring 2b are provided so as to cross the bent portion of flexible printed circuit board FPC1. Two pairs of first detection wiring 3 a and lead wiring 2 a and one pair of first detection wiring 3 b and lead wiring 2 b are each connected to touch detection control section TC of IC chip 1 . Other configurations are the same as in FIG. In addition, in the case of FIG. 19, the lead wirings 2a and 2b can also be regarded as sensor lines.

20A to 20C are cross-sectional views conceptually showing states in which the flexible printed circuit board of the display device according to the embodiment is folded. FIG. 20A is a sectional view showing a bent state of the flexible printed circuit board FPC1. FIG. 20B is a cross-sectional view showing a state in which the space between the backlight BLT and the flexible printed circuit board FPC1 is opened. FIG. 20C is a cross-sectional view showing a state in which the shield sheet SHLS and the flexible printed circuit board FPC1 are opened.

20A, 20B and 20C, the display device DSP has a backlight BLT, a display panel PNL, a polarizing plate POL and a cover glass CG. The back surface of the backlight BLT is connected to the second reference potential GND, and the display panel PNL, the polarizing plate POL and the cover glass CG are mounted in this order on the upper side of the backlight BLT. As shown in FIG. 19, the display panel PNL is connected to a flexible printed circuit board FPC1 provided with first detection wirings 3a and 3b. An IC chip 1 is mounted on the flexible printed circuit board FPC1, and a touch detection control section TC of the IC chip 1 is connected to first detection wirings 3a and 3b. Also, the flexible printed circuit board FPC1 is bent, and the IC chip 1 is arranged on the back side of the backlight BLT.

As shown in FIG. 20A, even when the flexible printed circuit board FPC1 is bent, it is possible to detect the influence of noise and the change in capacitance due to the variation in the space interval d2 of the bent portion by the first detection wirings 3a and 3b.

Further, as shown in FIG. 20B, even when the space between the backlight BLT and the flexible printed circuit board FPC1 is widened as indicated by the distance d3, the capacitance change between the backlight BLT and the flexible printed circuit board FPC1 can be detected by the first detection wirings 3a and 3b.

Furthermore, as shown in FIG. 20C, when a shield sheet SHLS is attached to the surface of the flexible printed circuit board FPC1 as a countermeasure against noise interference with the set, as shown in FIG. , the shield sheet SHLS and the flexible printed circuit board FPC1 are opened as indicated by a gap d4. Even in such a case, the change in capacitance between the shield sheet SHLS and the flexible printed circuit board FPC1 can be detected by the first detection wirings 3a and 3b. The flexible printed circuit board FPC1 is bent and the IC chip 1 is arranged on the back side of the backlight BLT.

FIG. 21 is a diagram illustrating still another schematic configuration of the display device according to the embodiment. In the display device DSP shown in FIG. 21, the first detection wirings 3c and 3d are arranged from the IC chip 1 to the lower end of the flexible printed circuit board FPC2 via the flexible printed circuit board FPC1. ing. A pair of lead wires 2a are arranged in the same manner as in FIG. Each of the first detection wirings 3 c and 3 d and the lead wiring 2 a is connected to the touch detection control section TC of the IC chip 1 . A bending portion BP exemplarily shows a portion where the flexible printed circuit board FPC1 is bent.

FIG. 22 is a diagram showing the back surface of the display device when the flexible printed circuit board FPC1 of FIG. 21 is folded. As shown in FIG. 22, the flexible printed circuit board FPC1 is bent at the bending portion BP, and the flexible printed circuit board FPC1 and the flexible printed circuit board FPC2 are arranged on the back side of the backlight BLT. In FIG. 22, only the first detection wirings 3c and 3d provided on the flexible printed circuit board FPC1 are drawn for simplification of the drawing, and the IC chip 1 and the lead wiring 2a are not drawn.

By providing the first detection wirings 3c and 3d, it is possible to detect and observe the adhesion between the flexible printed circuit board FPC2 and the back surface of the backlight BLT by means of the capacitance value in the region PC indicated by the round dotted line in FIG. It is possible. It is also possible to detect and observe the adhesion between the flexible printed circuit board FPC1 and the back surface of the backlight BLT based on the capacitance value.

23 is a sectional view conceptually showing a state in which the flexible printed circuit board of the display device shown in FIG. 21 is folded. In FIG. 23, the flexible printed circuit board FPC2 is peeled off from the back surface of the backlight BLT in the region PC indicated by the round dotted line, and a gap such as the distance d5 is generated between the flexible printed circuit board FPC2 and the back surface of the backlight BLT. It is in a state of

The first detection wirings 3c and 3d provided on the flexible printed circuit board FPC2 are driven by the touch detection controller TC of the IC chip 1 based on the self-detection method. As a result, the touch detection controller TC of the IC chip 1 can detect the capacitance values of the first detection wirings 3c and 3d. The occurrence of various gaps can be detected. That is, it is possible to electrically detect the occurrence of peeling between the flexible printed circuit board FPC2 and the back surface of the backlight BLT.

FIG. 24 is a diagram showing a detection method for detecting peeling of the flexible printed circuit board FPC2.

Step S20: The touch detection controller TC drives the touch sensors using the drive electrodes Tx1, Tx2, Tx3, . . . and the touch detection electrodes Rx1, Rx2, Rx3, .

Step S21: The touch detection controller TC drives the first detection wirings 3c and 3d based on the self-detection method. Thereby, the capacitance values of the first detection wirings 3c and 3d are detected.

Step S22: The touch detection controller TC determines whether the detected capacitance values of the first detection wirings 3c and 3d are lower than a predetermined value. If the detected capacitance values of the first detection wirings 3c and 3d are lower than the predetermined value (Yes), the process proceeds to step S23. Further, when the detected capacitance values of the first detection wirings 3c and 3d are higher than the predetermined value (No), the process proceeds to step S24.

Step S23: Since the detected capacitance values of the first detection lines 3c and 3d are lower than the predetermined value, the flexible printed circuit board FPC2 is peeled off from the back surface of the backlight BLT. Therefore, the touch detection control unit TC recognizes that a gap such as the distance d5 is generated between the flexible printed circuit board FPC2 and the back surface of the backlight BLT.

Step S24: Since the detected capacitance values of the first detection lines 3c and 3d are higher than the predetermined value, the flexible printed circuit board FPC2 is not peeled off from the back surface of the backlight BLT. Therefore, the touch detection control unit TC recognizes that the flexible printed circuit board FPC2 and the back surface of the backlight BLT are normally attached to each other.

The recognition results of steps S23 and S24 are notified to the host device connected to the flexible printed circuit board FPC2. For example, the host device notifies the user of the recognition results by displaying the recognition results on the display panel PNL. can.

Based on the display device described above as an embodiment of the present invention, all display devices that can be implemented by a person skilled in the art by appropriately modifying the design also belong to the scope of the present invention as long as they include the gist of the present invention.

Within the scope of the idea of the present invention, those skilled in the art can conceive of various modifications and modifications, and it is understood that these modifications and modifications also fall within the scope of the present invention. For example, additions, deletions, or design changes of components, or additions, omissions, or changes of conditions to the above-described embodiments by those skilled in the art are also subject to the gist of the present invention. is included in the scope of the present invention as long as it has

In addition, other actions and effects brought about by the aspects described in the present embodiment that are obvious from the description of the present specification or that can be appropriately conceived by those skilled in the art are naturally understood to be brought about by the present invention. .

Various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the above embodiments. For example, some components may be omitted from all components shown in the embodiments. Furthermore, constituent elements of different embodiments may be combined as appropriate.

DSP: display device, PNL: display panel, BTL: backlight device, FPC1, FPC2, FPC3: flexible printed circuit board, PX: display pixel, SUB1: first substrate (array substrate), SUB2: counter substrate, DA: display area, NDA: non-display area, TC: touch detection control unit, Tx1 to TX7: drive wiring, Rx1 to Rx5: detection wiring, SHL: shield wiring, 1: IC chip, 2: lead wiring, 3, 3a, 3b, 3c, 3d, 3G: first detection wiring, 31: second detection wiring, TPNL: touch panel, POL: polarizing plate, NOS: noise source

Claims (17)

an array substrate;
a counter substrate;
a flexible circuit board connected to the counter substrate;
a touch detection control unit provided on the array substrate or on the flexible circuit substrate;
a touch detection electrode provided on the counter substrate;
drawer wiring,
a first detection wiring;
The touch detection electrodes are connected to the touch detection control unit by the lead wires through the flexible circuit board,
the first detection wiring is arranged adjacent to the lead wiring and connected to the touch detection control unit ;
The lead wiring is arranged across the flexible circuit board and the array board,
The first detection wiring is arranged across the flexible circuit board and the array board,
display device. In claim 1,
A plurality of the lead wires are provided,
The display device, wherein the first detection wiring is arranged outside the plurality of lead wirings. In claim 2,
A plurality of the first detection wirings are provided,
The display device, wherein one of the plurality of first detection wirings is arranged next to each of the plurality of lead wirings. In claim 2 or claim 3,
including a shield wiring provided around the touch detection electrode;
The display device, wherein the shield wiring is connected to the first detection wiring. an array substrate;
a counter substrate;
a flexible circuit board connected to the counter substrate;
a touch detection control unit provided on the array substrate or on the flexible circuit substrate;
a touch detection electrode provided on the counter substrate;
drawer wiring,
a first detection wiring;
The touch detection electrodes are connected to the touch detection control unit by the lead wires through the flexible circuit board,
the first detection wiring is arranged adjacent to the lead wiring and connected to the touch detection control unit;
A plurality of the lead wires are provided,
The first detection wiring is arranged outside the plurality of lead wirings ,
The flexible circuit board is
a first flexible circuit board connected to the array board;
a second flexible circuit board connected to the counter substrate;
The second flexible circuit board is provided with the lead wiring and the first detection wiring,
A second detection wiring is provided on the first flexible circuit board at a position facing the first detection wiring,
A reference potential is applied to the second detection wiring,
The display device, wherein the first detection wiring is driven by a self-detection method. In claim 2 or claim 3,
detecting the coordinates of an external proximity object based on the variation of the touch detection electrodes;
A display device that stops detecting coordinates when a change in the first detection wiring is detected. In claim 2 or claim 3,
A display device, wherein the detection value of the first detection wiring is subtracted from the detection value of the touch detection electrode. In claim 2 or claim 3,
The display device, wherein the first detection wiring is connected to a reference potential and detects a change. In claim 2 or claim 3,
The display device, wherein the first detection wiring is driven by a self-detection method. an array substrate;
a counter substrate;
a flexible circuit board connected to at least one of the counter substrate and the array substrate;
a controller arranged on the flexible circuit board or on the array board;
a detection wiring provided on the flexible circuit board and connected to the control unit ;
The detection wiring is arranged across the flexible circuit board and the array board,
display device. In claim 10,
including a lead wiring provided adjacent to the detection wiring,
The lead wiring is driven by the control unit by a self-detection method,
The lead wiring is arranged across the flexible circuit board and the array board,
The detection wiring is driven by the self-detection method,
display device. a first substrate;
a second substrate facing the first substrate and provided with a plurality of touch detection electrodes;
a first flexible circuit board connected to the first substrate;
a second flexible circuit board connected to the second board;
a touch detection control unit provided on the first substrate or on the first flexible circuit substrate;
The second flexible circuit board includes: a plurality of lead wires electrically connected to the plurality of touch detection electrodes; and a plurality of lead wires arranged adjacent to the plurality of lead wires and not connected to any of the plurality of touch detection electrodes. and a first detection wiring,
the plurality of lead wires and the first detection wires are connected to the touch detection control unit ;
The lead wiring is arranged across the first flexible circuit board and the first board,
The first detection wiring is arranged across the first flexible circuit board and the first board,
display device. a first substrate;
a second substrate facing the first substrate and provided with a plurality of touch detection electrodes;
a first flexible circuit board connected to the first substrate;
a second flexible circuit board connected to the second board;
a touch detection control unit provided on the first substrate or on the first flexible circuit substrate;
The second flexible circuit board includes: a plurality of lead wires electrically connected to the plurality of touch detection electrodes; and a plurality of lead wires arranged adjacent to the plurality of lead wires and not connected to any of the plurality of touch detection electrodes. and a first detection wiring,
the plurality of lead wires and the first detection wires are connected to the touch detection control unit;
A display device, wherein the first flexible circuit board has a second detection wiring supplied with a predetermined DC voltage in a region facing the first detection wiring. In claim 13,
The display device, wherein the touch detection control unit detects a change in capacitance of the first detection wiring by a self-capacitance detection method. a first substrate;
a second substrate facing the first substrate and provided with a plurality of touch detection electrodes;
a first flexible circuit board connected to the first substrate;
a second flexible circuit board connected to the second board;
a touch detection control unit provided on the first substrate or on the first flexible circuit substrate;
The second flexible circuit board includes: a plurality of lead wires electrically connected to the plurality of touch detection electrodes; and a plurality of lead wires arranged adjacent to the plurality of lead wires and not connected to any of the plurality of touch detection electrodes. and a first detection wiring,
the plurality of lead wires and the first detection wires are connected to the touch detection control unit;
A display device, wherein the first flexible circuit board has a second detection wiring supplied with a predetermined AC voltage in a region facing the first detection wiring. In claim 15,
The display device, wherein the second detection wiring is connected to the touch detection control unit and detects a change in capacitance between the second detection wiring and the first detection wiring by a mutual detection method. In claim 12,
The display device, wherein the first flexible circuit board has a variation detection unit that detects a variation in potential of the first detection wiring.

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