The present invention relates to a touch sensor-equipped display device.
Patent Document 1 discloses a touch sensor-equipped display device that includes touch drive electrodes and touch detection electrodes. In this touch sensor-equipped display device, touch drive electrodes extend in a direction parallel to a direction in which scanning signals for driving pixel electrodes extend, the touch detection electrodes extend in a direction vertical to the direction in which scanning signals extend. Further, between adjacent ones of the touch detection electrodes, dummy electrodes are provided so that the touch detection electrodes become unnoticeable to human eye.
Here, in a case where the dummy electrodes are provided across a plurality of the touch drive electrodes, there is a possibility that a signal supplied to the touch drive electrodes could interfere via the dummy electrodes. The dummy electrodes, therefore, are divided at least not to be provided across a plurality of the touch drive electrodes.
Patent Document 1: JP-A-2014-130537
However, if the dummy electrodes are divided by lines parallel to the direction in which the touch drive electrodes extend, there is a possibility that during a period while the power source of the display device is OFF, or during a period while a dark image such as a black image is displayed, the dividing lines for the dummy electrodes can be visually recognized under a light source of approximately parallel light such as the sun light of the like.
It is an object of the present invention to provide a touch sensor-equipped display device in which dividing lines of the dummy electrodes are difficult to visually recognize.
A touch sensor-equipped display device in one embodiment of the present invention includes a display panel that includes: a first substrate; a second substrate opposed to the first substrate; and a display function layer interposed between the first substrate and the second substrate, the display function layer including a plurality of display pixels arranged in matrix. The touch sensor-equipped display device further includes: a plurality of touch drive electrodes arranged between the first substrate and the second substrate so as to be arrayed in a first direction, each of the touch drive electrodes extending in a second direction that intersects with the first direction at a right angle; a plurality of touch detection electrodes arranged on a surface of the first substrate, the surface being on an opposite side with respect to the touch drive electrodes, so as to be arrayed in the second direction, each of the touch detection electrodes extending in the first direction; and a dummy electrode arranged between adjacent ones of the touch detection electrodes, wherein a slit is provided in the dummy electrode, the slit being repeatedly bent in a zigzag shape, while extending in the first direction, and the dummy electrode is divided by, as a dividing line, a line parallel with either first edges or second edges, the first edges and the second edges forming the slit in the zigzag shape, so that the dummy electrode should not be provided across a plurality of the touch drive electrodes arrayed in the first direction.
According to the present invention, dividing lines that divide the dummy electrode are difficult to recognize, during a period while the power source of the display device is OFF, or during a period while a dark image such as a black image is displayed.
A touch sensor-equipped display device in one embodiment of the present invention includes a display panel that includes: a first substrate; a second substrate opposed to the first substrate; and a display function layer interposed between the first substrate and the second substrate, the display function layer including a plurality of display pixels arranged in matrix. The touch sensor-equipped display device further includes: a plurality of touch drive electrodes arranged between the first substrate and the second substrate so as to be arrayed in a first direction, each of the touch drive electrodes extending in a second direction that intersects with the first direction at a right angle; a plurality of touch detection electrodes arranged on a surface of the first substrate, the surface being on an opposite side with respect to the touch drive electrodes, so as to be arrayed in the second direction, each of the touch detection electrodes extending in the first direction; and a dummy electrode arranged between adjacent ones of the touch detection electrodes, wherein a slit is provided in the dummy electrode, the slit being repeatedly bent in a zigzag shape, while extending in the first direction, and the dummy electrode is divided by, as a dividing line, a line parallel with either first edges or second edges, the first edges and the second edges forming the slit in the zigzag shape, so that the dummy electrode should not be provided across a plurality of the touch drive electrodes arrayed in the first direction (the first configuration).
According to first configuration, a dividing line that divides the dummy electrode is difficult to recognize, during a period while the power source of the display device is OFF, or during a period while a dark image such as a black image is displayed. This makes it possible to improve appearance of the touch sensor-equipped display device in, for example, a power source OFF state.
In the first configuration, the dummy electrode is divided by, as a dividing line, a line obtained by extending either the first edge or the second edge, the first edges and the second edges forming the slit in the zigzag shape (the second configuration).
According to the second configuration, a line obtained by extending either the first edges or the second edges, the first edges and the second edges forming the slit.
This makes the dividing line more difficult to visually recognize.
The following describes embodiments of the present invention in detail, while referring to the drawings. Identical or equivalent parts in the drawings are denoted by the same reference numerals, and the descriptions of the same are not repeated. To make the description easy to understand, in the drawings referred to hereinafter, the configurations are simply illustrated or schematically illustrated, or the illustration of a part of constituent members is omitted. Further, the dimension ratios of the constituent members illustrated in the drawings do not necessarily indicate the real dimension ratios.
The liquid crystal panel 11 with a touch sensor function has a function of displaying an image, and a touch sensor function of detecting a touched position. More specifically, the liquid crystal panel 11 with a touch sensor function has a configuration that includes: a liquid crystal panel (display panel) that includes a pair of substrates and a display function layer provided between the substrates, the display function layer including a plurality of display pixels provided in matrix; touch drive electrodes provided between the pair of substrates of the liquid crystal panel; and touch detection electrodes provided on a front side of the substrate on the front side of the display panel.
The backlight device 13 is an external light source that emits light toward the liquid crystal panel 11 with a touch sensor function.
The cover 16 is arranged on an outer side of the liquid crystal panel 11 with a touch sensor function so as to protect the liquid crystal panel 11 with a touch sensor function. This cover 16 is made of a material that has excellent impact resistance, for example, tempered glass. The liquid crystal panel 11 with a touch sensor function, and the cover 16, are bonded and integrated with each other with an approximately transparent adhesive (not shown) being interposed therebetween.
The bezel 14 holds the cover 16 and the liquid crystal panel 11 with a touch sensor function together, between the same and the backlight device 13. The bezel 14 is attached to the case 15, and the case 15 houses the backlight device 13.
The liquid crystal panel 11 with a touch sensor function includes a pair of substrates 11a and 11b that are transparent (that have excellent translucency), and a liquid crystal layer 11c interposed between the substrates 11a and 11b, as illustrated in
Each of the substrates 11a and 11b includes an approximately transparent glass substrate, and has such a configuration that a plurality of films are laminated on the glass substrate by a known photolithography method or the like. Among the substrates 11a and 11b, the CF substrate (first substrate) 11a is on the front side, and the array substrate (second substrate) 11b is on the rear side (back side).
On the inner side surfaces of the substrates 11a and 11b, alignment films 11d and 11e for aligning the liquid crystal molecules contained in the liquid crystal layer 11c are formed, respectively, as illustrated in
On the inner side surface of the array substrate 11b (the liquid crystal layer 11c side, the side opposed to the CF substrate 11a), a plurality of thin film transistors (TFTs) 17, which are switching elements, and a plurality of pixel electrodes 18, are provided in matrix, as illustrated in
The gate lines 19 and the source lines 20 are connected to the gate electrodes and the source electrodes of the TFTs 17, respectively, and the pixel electrodes 18 are connected to the drain electrodes of the TFTs 17. Further, each pixel electrode 18 is in a portrait oriented rectangular shape when viewed in a plan view, and is formed with a translucent conductive film made of a material having excellent translucency and conductivity, such as indium tin oxide (ITO) or zinc oxide (ZnO).
On the other hand, as illustrated in
In this liquid crystal panel 11 with a touch sensor function, as illustrated in
The following describes the touch sensor function. The liquid crystal panel 11 with a touch sensor function includes touch drive electrodes 61 and touch detection electrodes 62 that compose the touch sensor. As illustrated in
The following simply explains a method for detecting a touched position. The touch drive electrodes 61 are sequentially scanned so that an input signal is input thereto, and output signals output from the touch detection electrodes 62 are detected. When any area of the surface of the touch sensor-equipped display device 10 is touched, the electrostatic capacitance between the touch drive electrode 61 and the touch detection electrode 62 at the touched position changes. Based on an output signal output from the touch detection electrode 62, the position where the electrostatic capacitance has changed is detected, and the detected position is identified as the touched position.
Between the plurality of the touch detection electrodes 62 provided on the front side of the CF substrate 11a, the dummy electrodes 63 are provided. In other words, in each space between adjacent ones of the plurality of touch detection electrodes 62 arrayed in the X axis direction at predetermined intervals, a plurality of dummy electrodes 63 extending in the Y axis direction are provided.
The dummy electrodes 63 are provided for the purpose of preventing the light transmission rate and the like from becoming different between the positions where the touch detection electrodes 62 are provided and the positions where they are not provided, on the front side of the CF substrate 11a. The dummy electrodes 63, therefore, are formed with conductive films made of the same material as that of the touch detection electrodes 62, that is, a material having excellent translucency, such as ITO or ZnO. It should be noted that the dummy electrodes 63 are not connected with other lines or electrodes, and are in an electrically floating state.
The touch detection electrodes 62 and the dummy electrodes 63 have predetermined refractive indices, though they are transparent. In the touch detection electrodes 62 and the dummy electrodes 63, therefore, a plurality of slits are provided so as to make the touch detection electrodes 62 and the dummy electrodes 63 unnoticeable when the touch sensor-equipped liquid crystal display device 10 is viewed.
The dummy electrode 63 is composed of a plurality of electrode portions 631 formed with translucency conductive films and a plurality of slits 632 formed between the electrode portions 631. Each slit 632 is repeatedly bent in a zigzag shape, while, as an entire slit, extending in the Y axis direction. In other words, the slit 632 is composed of first direction linear portions 632a extending in a first direction, and second direction linear portions 632b extending in a second direction that is different from the first direction.
Here, the first direction linear portions 632a and the second direction linear portions 632b have the same width in the X axis direction, and the same length in the Y axis direction.
Here, as illustrated in
As described above, the dummy electrodes 63 are formed with conductive films made of a material having excellent translucency, such as ITO or ZnO. Since each of edge portions 91 of conductive films 90 is tilted in a taper shape as illustrated in
In a case where the dummy electrode 63 is divided by the lines 80 parallel with the X axis as illustrated in
On the other hand, when viewed in the direction indicated by the arrow Y2 in
In the touch sensor-equipped display device of the present embodiment, therefore, the dummy electrode 63 is divided by dividing lines so that the dummy electrode 63 should not be provided across a plurality of the touch drive electrodes 61 arrayed in the Y axis direction, the dividing lines being lines parallel to either the first direction linear portions 632a or the second direction linear portions 632b that form the slit 632 in the zigzag shape. Particularly in the present embodiment, the dummy electrode 63 is divided by dividing lines that are obtained by extending either the first direction linear portions 632a or the second direction linear portions 632b of the linear portion slit 632.
As described above, slits are provided not only in the dummy electrodes 63 but also in the touch detection electrodes 62.
The touch detection electrode 62 is composed of a plurality of electrode portions 621 formed with translucent conductive films, and a plurality of slits 622 provided between the plurality of electrode portions 621. Each slit 622 is repeatedly bent in a zigzag shape, while extending in the Y axis direction in a plan view. In other words, each slit 622 is composed of first direction linear portions 622a extending in a first direction, and second direction linear portions 622b extending in a second direction that is different from the first direction. Here, the first direction linear portions 622a and the second direction linear portions 622b have the same width in the X axis direction, and the same length in the Y axis direction.
In the present embodiment, an arrangement interval “a” for the slits 622 adjacent in the X axis direction in a plan view satisfies the relationship given as the following expression (1):
a=b×(0.725+n)×√3÷(2×cos θ) (1)
where “b” represents an interval for a plurality of the display pixels adjacent in the X axis direction in a plan view, “θ” represents an angle of the slit 622 with respect to the Y axis direction as a reference direction, and “n” represents an integer equal to or greater than 0 (n=0, 1, 2, . . . ).
Further, the tumback width “c” of the slit 622 in the zigzag shape is set to (the distance between the centers of the subpixels adjacent in the X axis direction among the plurality of subpixels composing one display pixel)×{a natural number equal to or greater than (the number of colors of the subpixels+1)}. The tumback width “c” of the slit 622 is a width of the first direction linear portion 622a (or the second direction linear portion 622b) in the X axis direction. For example, in a case where the subpixels correspond to the three colors of R (red), G (green), and B (blue), the tumback width “c” of the slit 622 is assumed to be {(the distance between the centers of the subpixels)×(a natural number equal to or greater than 4)}. In the present embodiment, the tumback width “c” of the slit 622 is set to {(the distance between the centers of the subpixels)×4}.
It is preferable that the width “d” of the slit 622 in the X axis direction is 20 Lm or less. Further, it is preferable that the arrangement interval “a” of the slits 622 adjacent in the X axis direction is 175 μm or less.
The angle θ of the slit 622 is preferably 25° to 45°, and is set to 30° in the present embodiment.
In the case where the arrangement interval “a” for the slits 622 is set to 1.000 time the arrangement interval “b” for the display pixels, wide horizontal lines are visible as moire, as illustrated in
On the other hand, in the case where the arrangement interval “a” for the slits 622 is set to 1.725 times the arrangement interval “b” for the display pixels so as to satisfy the relationship given as the expression (1), clear moire is not seen as illustrated in
The present invention is not limited to the above-described embodiment. For example, the foregoing description refers to a liquid crystal panel as an exemplary display panel in which a display function layer including a plurality of display pixels arranged in matrix is provided between a pair of substrates, but the display panel may be another display panel such as an organic electroluminescence (EL) panel including organic EL elements.
The foregoing description refers to an example in which the dummy electrode 63 is divided by using, as the dividing lines, the lines obtained by extending the first direction linear portions 632a or the second direction linear portions 632b composing the slit 632 of the dummy electrode 63, but the dummy electrode 63 may be divided by using, as the dividing lines, the lines parallel to the first direction linear portions 632a or the second direction linear portions 632b composing the slit 632, whereby the dividing lines are difficult to recognize.
In the foregoing description, the colors of the subpixels are three colors of R (red), G (green), and B (blue), but the colors may be four colors of R (red), G (green), B (blue), and Y (yellow), or alternatively, five or more colors.
The touch sensor-equipped display device in the present embodiment is used in various types of electronic devices such as mobile phones (including smartphones), notebook computers (including tablet-type notebook computers), portable information terminals (including electronic books and PDAs), digital photoframes, and portable game machines.
Number | Date | Country | Kind |
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2015-033443 | Feb 2015 | JP | national |
Filing Document | Filing Date | Country | Kind |
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PCT/JP2016/055043 | 2/22/2016 | WO | 00 |