JP5555142B2 - Display device - Google Patents

Description

  The present invention relates to a display device with a touch panel.

  A terminal that can be intuitively input by overlapping a touch panel on a display surface of a display panel that displays images and character information is used (Patent Document 1). In addition, products that meet the demands for stereoscopic display of images have been developed, and liquid crystal display devices equipped with a parallax barrier liquid crystal panel for naked-eye viewing, such as mobile phones and portable information terminals. Is known (Patent Document 2).

JP-A-8-234162 JP 2004-294862 A

  In the prior art, when an autostereoscopic display device provided with a touch panel is to be configured, three types of liquid crystal display panel, liquid crystal panel for parallax barrier, and touch panel are separately manufactured and stacked. Therefore, there are problems such as an increase in the overall thickness and a decrease in transmittance due to the influence of interface reflection when transmitting through the three types of panels.

  An object of the present invention is to reduce the thickness of a display device that has an input function based on touch detection and enables autostereoscopic viewing, and to suppress deterioration of optical characteristics due to the influence of interface reflection.

  (1) A display device according to the present invention includes a display panel, a parallax barrier panel for separating a left-eye image and a right-eye image displayed on the display panel to enable autostereoscopic viewing, and parallax barrier driving The parallax barrier panel includes a circuit, a capacitive touch panel, a touch panel drive circuit, and a touch input detection circuit, and the parallax barrier panels are opposed to each other so that a gap is formed therebetween. A first electrode pattern formed on a first surface of the first substrate on the second substrate side, a second electrode pattern formed on a second surface of the second substrate on the first substrate side, and the first substrate And a liquid crystal disposed between the first substrate and the second substrate, wherein the first substrate is disposed to face the display panel, and the parallax barrier driving circuit includes the liquid crystal forming a parallax barrier. As described above, the first electrode pattern And a driving voltage of the liquid crystal is applied between the second electrode pattern, the touch panel includes the second substrate, the second electrode pattern formed on the second surface of the second substrate, and the second electrode pattern. A third electrode pattern formed on a third surface opposite to the second surface of the two substrates, wherein the touch panel drive circuit inputs a sensing signal to the second electrode pattern and detects the touch input The circuit measures an output signal generated in the third electrode pattern by the sensing signal by electrostatic induction, and detects presence / absence of a touch input according to a change in the output signal accompanying a change in the capacitance. . According to the present invention, since the parallax barrier panel and the touch panel are shared by the second substrate, the number of substrates can be reduced. Thereby, the thickness of the display device can be reduced, and the deterioration of the optical characteristics due to the influence of interface reflection can be suppressed.

  (2) In the display device described in (1), each of the second electrode pattern and the third electrode pattern includes a plurality of stripe electrodes arranged in parallel, and the second electrode pattern extends in the extending direction. The direction in which the three-electrode pattern extends may be orthogonal.

  (3) In the display device described in (1) or (2), the second electrode pattern includes a plurality of common electrodes to which the liquid crystal driving signal and the sensing signal are applied, and the liquid crystal driving signal. And a plurality of dedicated electrodes to which the sensing signal is not applied.

  (4) In the display device described in (3), one common electrode and two or more dedicated electrodes may be alternately arranged.

  (5) In the display device described in any one of (1) to (4), the third electrode pattern includes a plurality of detection electrodes electrically connected to the touch input detection circuit, and the touch. And a plurality of non-detection electrodes that are not electrically connected to the input detection circuit.

  (6) In the display device described in (5), one detection electrode and two or more non-detection electrodes may be alternately arranged.

  (7) In the display device described in any one of (1) to (6), the driving voltage of the liquid crystal is an AC voltage for inversion driving of the liquid crystal, and the sensing signal is The pulse signal may be shorter than the time required for the response of the liquid crystal.

  (8) In the display device described in (7), the AC voltage is a rectangular wave voltage, and the pulse signal is input while avoiding a timing at which the phase of the rectangular wave voltage is inverted. Good.

  (9) In the display device described in any one of (1) to (8), the touch input detection circuit measures the output signal at a plurality of positions, and measures the measured values at two or more adjacent positions. In comparison, the position where the touch input is made may be specified.

It is sectional drawing which shows the display apparatus with a touchscreen which concerns on embodiment of this invention. It is a top view of the 2nd board | substrate shown in FIG. It is a figure explaining the 2nd board | substrate and circuit shown in FIG. It is a figure explaining the waveform and input timing of the signal input into a 2nd electrode pattern. It is a figure which shows the 2nd board | substrate of the display apparatus which concerns on the modification 1 of embodiment. It is a figure which shows the 2nd board | substrate of the display apparatus which concerns on the modification 2 of embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a cross-sectional view showing a display device with a touch panel according to an embodiment of the present invention.

  The display device has a display panel 10. A display panel 10 shown in FIG. 1 is a liquid crystal panel, and includes a pair of transparent substrates 12 and 14 made of glass or the like, and a liquid crystal 15 is sandwiched between them and sealed with a seal 16. One substrate 12 is a TFT (Thin Film Transistor) substrate, and the other substrate 14 is a color filter substrate. Polarizing plates 18 are attached to the surfaces of the pair of substrates 12 and 14 opposite to each other. An integrated circuit chip 20 is mounted on the substrate 12 and a flexible wiring substrate 22 is attached thereto. The flexible wiring board 22 has a wiring pattern (not shown), and can be electrically connected to the display panel 10 by using an anisotropic conductive film for attachment. The flexible wiring board 22 includes a connector 24 as an interface terminal for electrical connection with the outside.

  A light emitting component 26 such as a light emitting diode is mounted on the flexible wiring board 22. The light emitting component 26 serves as a light source for the backlight 28. The backlight 28 further includes a light guide plate 30, an optical film 32, and a reflective film 34, and the details thereof are well known, and thus description thereof is omitted. The display panel 10 and the backlight 28 are supported by a frame 36 formed by resin molding.

  The liquid crystal panel is not limited to a structure or a system such as a TN (Twisted Nematic) type, an STN (Super Twisted Nematic) type, a VA (Vertical Alignment) system, an IPS (In-Plane Switching) system, etc. The display panel 10 However, the present invention is not limited to the liquid crystal panel, and an organic electroluminescence panel can also be used, etc. The display panel 10 is driven so that an image is displayed.

  The display device according to the present embodiment enables stereoscopic image display. Specifically, different two-dimensional images are recognized by the left and right eyes of the person, and the brain constructs a three-dimensional space based on the two two-dimensional images. Therefore, the left eye image and the right eye image are displayed on the display panel 10.

  The display device includes a parallax barrier panel 38. The parallax barrier panel 38 is for separating a left eye image and a right eye image displayed on the display panel 10 by a parallax barrier method (parallax barrier method) to enable autostereoscopic viewing. The parallax barrier method (parallax barrier method) is a vertical stripe filter (parallax barrier) superimposed on the image display surface, so that only the left-eye image is displayed on the left eye and only the right-eye image is displayed on the right eye This is the method.

  The parallax barrier panel 38 includes a first substrate 40 and a second substrate 42 that face each other so that a gap is formed therebetween. Both the first substrate 40 and the second substrate 42 are made of transparent glass or the like. A liquid crystal 44 is sandwiched between the two and sealed with a seal 46. Polarizing plates 48 are attached to the opposite surfaces of the first substrate 40 and the second substrate 42, respectively. That is, the parallax barrier panel 38 is also a liquid crystal panel. However, in this embodiment, the display panel 10 described above is an active matrix type liquid crystal panel suitable for displaying an image, whereas the parallax barrier panel 38 forms a parallax barrier (a striped filter). Therefore, the passive matrix method is applied because characteristics suitable for moving images and high definition are not required.

  The parallax barrier panel 38 and the display panel 10 described above are overlapped and fixed. The first substrate 40 is disposed so as to face the display panel 10 and is bonded by an adhesive 50 (for example, an ultraviolet curable adhesive). Specifically, the polarizing plate 48 of the parallax barrier panel 38 and the polarizing plate 18 of the display panel 10 are bonded.

  The parallax barrier panel 38 includes a first electrode pattern 54 formed on the first surface 52 of the first substrate 40 on the second substrate 42 side. The first electrode pattern 54 is covered with an alignment film 56. The parallax barrier panel 38 includes a second electrode pattern 60 formed on the second surface 58 of the second substrate 42 on the first substrate 40 side. The second electrode pattern 60 is also covered with the alignment film 56. The liquid crystal 44 is driven by a voltage applied between the first electrode pattern 54 and the second electrode pattern 60. Both the first electrode pattern 54 and the second electrode pattern 60 are made of a transparent conductive material such as ITO (Indium Tin Oxide).

  FIG. 2 is a plan view of the second substrate 42. The second electrode pattern 60 includes a plurality of stripe electrodes corresponding to the stripes in order to form a striped filter (parallax barrier). On the other hand, the first electrode pattern 54 shown in FIG. 1 may be composed of a plurality of stripe electrodes, or may be one common electrode facing the entire second electrode pattern 60.

  FIG. 3 is a diagram illustrating the second substrate 42 and the circuit. The display device includes a parallax barrier driving circuit 62. The parallax barrier driving circuit 62 applies a driving voltage for the liquid crystal 44 between the first electrode pattern 54 and the second electrode pattern 60 shown in FIG. 1 so that the liquid crystal 44 forms a parallax barrier. The drive voltage of the liquid crystal 44 is an alternating voltage for driving the liquid crystal 44 in an inverted manner. By inversion driving, deterioration of the liquid crystal 44 is prevented.

  FIG. 4 is a diagram for explaining the waveform and input timing of a signal input to the second electrode pattern 60. A rectangular wave driving signal SD shown in FIG. 4 (upper) is input to the second electrode pattern 60 so that a rectangular wave voltage is applied as the driving voltage, and the first electrode pattern 54 is set to the ground potential.

  As shown in FIG. 1, the display device includes a capacitive touch panel 64. The touch panel 64 includes the second substrate 42 described above. In other words, the second substrate 42 that is a part of the parallax barrier panel 38 is also a part of the touch panel 64. The touch panel 64 includes a second electrode pattern 60 formed on the second surface 58 of the second substrate 42. In other words, the second electrode pattern 60 that is a part of the parallax barrier panel 38 is also a part of the touch panel 64. As shown in FIG. 2, the second electrode pattern 60 includes a plurality of stripe electrodes arranged in parallel. As shown in FIG. 1, the touch panel 64 includes a third electrode pattern 68 formed on a third surface 66 opposite to the second surface 58 of the second substrate 42. The third electrode pattern 68 is made of a transparent conductive material such as ITO (Indium Tin Oxide) and is covered with a transparent insulating film 69. A polarizing plate 48 is attached on the insulating film 69. The third electrode pattern 68 includes a plurality of stripe electrodes arranged in parallel. The direction in which the stripe electrodes constituting the second electrode pattern 60 extend is perpendicular to the direction in which the stripe electrodes constituting the third electrode pattern 68 extend (see FIG. 2).

  As shown in FIG. 3, the display device includes a touch panel drive circuit 70. The touch panel drive circuit 70 inputs a sensing signal SS to the second electrode pattern 60. The sensing signal SS is a pulse signal having a shorter time than the time required for the response of the liquid crystal 44, as shown in FIG. The pulse signal in FIG. 4 (middle stage) is input while avoiding the timing at which the phase of the drive signal SD (or drive voltage or rectangular wave voltage applied by the drive signal SD) in FIG. 4 (upper stage) is inverted.

  The display device has a touch input detection circuit 72. The touch input detection circuit 72 measures an output signal generated in the third electrode pattern 68 by the sensing signal SS by electrostatic induction. The presence or absence of touch input is detected by the change in the output signal accompanying the change in the capacitance. The touch input detection circuit 72 measures output signals at a plurality of positions, compares the measured values at two or more adjacent positions, and identifies the position where the touch input is made.

  As shown in FIG. 1, a first flexible wiring board 74 is attached to the first board 40. The first flexible wiring board 74 is electrically connected to the first electrode pattern 54 and the second electrode pattern 60. The electrical connection between the second electrode pattern 60 and the first flexible wiring board 74 is made by a conductive member (for example, conductive beads) (not shown) provided between the first board 40 and the second board 42. Then, the second electrode pattern 60 is electrically connected to the parallax barrier driving circuit 62 and the touch panel driving circuit 70 (see FIG. 3) through the first flexible wiring board 74, and the application of the driving voltage of the liquid crystal 44 (the driving signal SD). And the sensing signal SS are input.

  As shown in FIGS. 1 and 2, a second flexible wiring substrate 76 is attached to the second substrate 42. The second flexible wiring board 76 is electrically connected to the third electrode pattern 68. An output signal corresponding to the presence or absence of touch input is output from the third electrode pattern 68 through the second flexible wiring board 76.

  According to this embodiment, since the parallax barrier panel 38 and the touch panel 64 share the second substrate 42, the number of substrates can be reduced. Thereby, the thickness of the display device can be reduced, and the deterioration of the optical characteristics due to the influence of interface reflection can be suppressed.

  In the present embodiment, a left eye image and a right eye image are displayed on the display panel 10 for stereoscopic image display. In order to separate the left eye image and the right eye image, a parallax barrier is formed on the parallax barrier panel 38. Specifically, a voltage is applied between the first electrode pattern 54 and the second electrode pattern 60 sandwiching the liquid crystal 44 to display a striped image corresponding to the parallax barrier on the parallax barrier panel 38. For this purpose, the drive signal SD is input from the parallax barrier drive circuit 62 shown in FIG. 3 to the second electrode pattern 60 as shown in FIG. The drive signal SD is an AC signal (rectangular wave signal) for driving the liquid crystal 44 in an inverted manner.

  In the present embodiment, a sensing signal SS is input to the touch panel 64 for touch input. The sensing signal SS is input to the second electrode pattern 60 by the touch panel drive circuit 70. The sensing signal SS is a pulse signal shorter than the time required for the response of the liquid crystal 44 (see FIG. 4 (middle stage)). The pulse signal is input avoiding the timing at which the phase of the rectangular wave voltage is inverted.

  In the present embodiment, since both the drive signal SD of the liquid crystal 44 and the sensing signal SS are input to the second electrode pattern 60, the synthesized signal SC is as shown in FIG. 4 (lower stage). Accordingly, an output signal is generated in the third electrode pattern 68 by electrostatic induction corresponding to the composite signal SC shown in FIG. 4 (lower stage). The output signal includes a signal corresponding to the sensing signal SS. If a signal corresponding to the drive signal SD of the liquid crystal 44 is removed through a filter (not shown), only an output signal corresponding to the sensing signal SS can be extracted, and this is detected by the touch input detection circuit 72.

  The output signal detected by the touch input detection circuit 72 is a constant signal corresponding to the sensing signal SS if there is no touch input, but if there is a touch input, the waveform of the output signal is distorted. Therefore, the presence or absence of touch input can be detected by comparison with a waveform stored in advance.

  Note that the distortion of the waveform of the output signal may be caused by noise, but by comparing the measured values at two or more adjacent positions and removing the distortion unrelated to the change in capacitance, The position where the touch input is made can be specified more accurately.

[Modification 1]
FIG. 5 is a diagram illustrating a second substrate of the display device according to the first modification of the embodiment. In this example, the second electrode pattern 160 includes a plurality of shared electrodes 178 to which both the drive signal SD and the sensing signal SS of the liquid crystal 44 illustrated in FIG. 1 are applied. The second electrode pattern 160 includes a plurality of dedicated electrodes 180 to which the driving signal SD of the liquid crystal 44 is applied but the sensing signal SS is not applied. One common electrode 178 and two or more dedicated electrodes 180 are alternately arranged. The pitch of the adjacent shared electrodes 178 is about 5 mm.

  According to this, since touch input scanning is not performed for all of the plurality of stripe electrodes constituting the second electrode pattern 160, the scanning time required for the detection can be shortened.

[Modification 2]
FIG. 6 is a diagram illustrating a second substrate of the display device according to the second modification of the embodiment. In this example, the third electrode pattern 268 includes a plurality of detection electrodes 282 that are electrically connected to the touch input detection circuit 72 (see FIG. 3). The third electrode pattern 268 includes a plurality of non-detection electrodes 284 that are not electrically connected to the touch input detection circuit 72 (see FIG. 3). One detection electrode 282 and two or more non-detection electrodes 284 are alternately arranged. The non-detection electrode 284 is in an electrically floating state. The detection electrode 282 and the non-detection electrode 284 are preferably made of the same material, have the same surface reflectance, and preferably have the same width. In addition, it is preferable that the plurality of detection electrodes 282 and the plurality of non-detection electrodes 284 are arranged at an equal pitch.

  According to this, although the several detection electrode 282 is arrange | positioned at intervals, since the non-detection electrode 284 is arrange | positioned at the space | interval, it can improve appearance. In addition, you may combine the content demonstrated in the said modification 1 with this example.

  The present invention is not limited to the above-described embodiments, and various modifications can be made. For example, the configuration described in the embodiment can be replaced with substantially the same configuration, a configuration that exhibits the same operational effects, or a configuration that can achieve the same purpose.

  SD drive signal, SS sensing signal, SC composite signal, 10 display panel, 12 substrate, 14 substrate, 15 liquid crystal, 16 seal, 18 polarizing plate, 20 integrated circuit chip, 22 flexible wiring substrate, 24 connector, 26 light emitting component, 28 Backlight, 30 light guide plate, 32 optical film, 34 reflective film, 36 frame, 38 parallax barrier panel, 40 first substrate, 42 second substrate, 44 liquid crystal, 46 seal, 48 polarizing plate, 50 adhesive, 52 first Surface, 54 first electrode pattern, 56 alignment film, 58 second surface, 60 second electrode pattern, 62 parallax barrier drive circuit, 64 touch panel, 66 third surface, 68 third electrode pattern, 69 insulating film, 70 touch panel drive Circuit, 72 touch input detection circuit, 74 first flexible wiring board, 76 2nd flexible wiring board, 160 2nd electrode pattern, 178 shared electrode, 180 exclusive electrode, 268 3rd electrode pattern, 282 detection electrode, 284 non-detection electrode.

Claims (9)

A display panel;
A parallax barrier panel for separating a left eye image and a right eye image displayed on the display panel to enable autostereoscopic viewing;
A parallax barrier driving circuit;
A capacitive touch panel,
A touch panel drive circuit;
A touch input detection circuit;
Have
The parallax barrier panel includes a first substrate and a second substrate facing each other so as to form a gap, and a first electrode pattern formed on a first surface of the first substrate on the second substrate side, A second electrode pattern formed on a second surface of the two substrates on the first substrate side, and a liquid crystal disposed between the first substrate and the second substrate, wherein the first substrate is the display Arranged to face the panel,
The parallax barrier driving circuit such that said liquid crystal to form a parallax barrier, and applying the liquid crystal driving voltage to the second electrode pattern of the first electrode pattern as a ground potential,
The touch panel is formed on the second substrate, the second electrode pattern formed on the second surface of the second substrate, and a third surface opposite to the second surface of the second substrate. A third electrode pattern,
The touch panel drive circuit inputs a sensing signal to the second electrode pattern,
The touch input detection circuit measures an output signal generated in the third electrode pattern by the sensing signal by electrostatic induction, and detects presence / absence of a touch input by a change in the output signal accompanying a change in the capacitance. A display device. The display device according to claim 1,
Each of the second electrode pattern and the third electrode pattern includes a plurality of stripe electrodes arranged in parallel,
A display device, wherein a direction in which the second electrode pattern extends and a direction in which the third electrode pattern extends are orthogonal to each other. The display device according to claim 1 or 2,
The second electrode pattern includes a plurality of common electrodes to which the liquid crystal driving signal and the sensing signal are applied, and a plurality of dedicated electrodes to which the liquid crystal driving signal is applied but the sensing signal is not applied. A display device including the display device. The display device according to claim 3,
A display device, wherein one shared electrode and two or more dedicated electrodes are alternately arranged. The display device according to any one of claims 1 to 4,
The third electrode pattern includes a plurality of detection electrodes electrically connected to the touch input detection circuit and a plurality of non-detection electrodes not electrically connected to the touch input detection circuit. Display device. The display device according to claim 5,
A display device, wherein one detection electrode and two or more non-detection electrodes are alternately arranged. The display device according to any one of claims 1 to 6,
The driving voltage of the liquid crystal is an alternating voltage for driving the liquid crystal in an inverted manner,
The display device, wherein the sensing signal is a pulse signal having a shorter time than the time required for the response of the liquid crystal. The display device according to claim 7,
The AC voltage is a rectangular wave voltage,
The display device according to claim 1, wherein the pulse signal is inputted avoiding a timing at which a phase of the rectangular wave voltage is inverted. The display device according to any one of claims 1 to 8,
The touch input detection circuit measures the output signal at a plurality of positions, compares measured values at two or more adjacent positions, and identifies a position where the touch input is made. apparatus.

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