JPH0916331A - Display device with tablet - Google Patents

Abstract

PURPOSE: To exactly discriminate the instructed area of a display screen by improving a tablet so as to exactly detect an instructed coordinate. CONSTITUTION: This device is provided with a tablet 2 having two substrates of a transparent glass 3 for which a first transparent electrode is formed on one surface and a transparent film 4 for which a second transparent electrode is formed on one surface and which is stuck on the transparent glass 3, and liquid crystal display panel 1 constituted of the number of dots in one side direction less than the number of dots in the other side direction orthogonal to the one side direction and mounted with the tablet on the display screen, and concerning the tablet 2, the electrode of worse linearity between the first and second transparent electrodes is made to match the side direction of the less number of dots on the liquid crystal display panel 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device with a tablet in which a transparent tablet is arranged on the screen of the display device.

[0002]

2. Description of the Related Art Conventionally, a transparent tablet is arranged on the screen of a display device, and while visually recognizing the displayed screen, the corresponding display position is pressed by a fingertip or the like to indicate the position by the tablet. Various display devices with a tablet called a touch panel, a touch screen, or the like, which are capable of capturing and inputting as coordinate positions, are provided.

A tablet used in such a display device with a tablet is, for example, a first transparent substrate having a first electrode such as a transparent resistance film for detecting the X or Y direction on one surface. And Y or X on one side
A flexible second transparent substrate on which a second electrode such as a transparent resistance film for direction detection is formed, and the first and second transparent substrates are the first and second transparent substrates. The electrodes are placed inside, and the electrodes are attached to each other via a transparent insulating spacer. When the flexible second transparent substrate is pressed with a fingertip or a pen tip, the resistance of the second resistance film changes and
The transparent substrate is curved so that the first resistance film is also pressed to change the resistance, and the coordinates of the pressed portion are detected from the resistance changes of these two resistance films. The first transparent substrate is composed of, for example, a transparent glass plate, and the second transparent substrate is composed of a flexible synthetic resin film such as polyethylene terephthalate.

As described above, since the resistance film and the substrate of the tablet are made of a transparent body, when the tablet is installed in front of a liquid crystal display device or a CRT which is a display device, the display screen is visually recognized through the tablet. can do. Therefore, the user can input the coordinate signal of the pressing portion according to the display content by operating the tablet while visually recognizing the display content of the display screen, and the interactive input operation can be executed with a simple system configuration. .

[0005]

The above-mentioned second problem
When an electrode such as a resistance film is formed on the synthetic resin film which is the transparent substrate of, the synthetic resin film usually wound in a roll shape is pulled out, that is, by vapor deposition along the winding direction of the roll. A resistance film is attached, and extraction electrodes are provided at both ends in the winding direction of the synthetic resin film cut into a desired length. On the other hand, when the resistance film is formed on the glass plate which is the first transparent substrate described above, a predetermined sputtering method or a CVD method in which a liquid resistance material is atomized and sprayed is used. A method of applying a film on the surface of glass cut to the size of is adopted.

Therefore, in the case of a synthetic resin film,
There is little variation in the resistance value with respect to the winding direction of the roll, and the resistance value is almost uniform.However, in the case of a glass plate, the film is attached to each sheet, so there is a variation in which the resistance value varies from sheet to sheet. This is easy, and when the glass plate is put into the production line of the CVD method, the heat of the glass plate itself is different between the line introduction side and the opposite side, and this heat causes variations in the resistance value. For this reason, the linearity of the resistance value on the glass plate side is worse than that on the synthetic resin film side. Therefore, there is a possibility that the tablet side may cause an erroneous detection such that the tablet side cannot accurately detect the finger even though the user's fingertip points at a predetermined area of the display screen.

The first object of the present invention is to provide the first transparent structure by arranging the structure of the conventional tablet in which the electrode having the poor linearity is located at the side of the liquid crystal means having a small number of dots, which is extremely simple. The amount of deviation between the electrode direction and the second transparent electrode direction, that is, the X direction and the Y direction in the tablet can be averaged, the tablet can accurately detect the indicated coordinates, and the indication in the display screen of the display means can be obtained. An object of the present invention is to provide an inexpensive display device with a tablet capable of accurately discriminating the created area.

A second object of the present invention is to apply to a tablet in which a transparent electrode is composed of a resistance film which is likely to cause variations in linearity at the time of manufacture, so that the defect of the resistance film can be improved. To provide.

A third object of the present invention is to even out variations in linearity that occur when the first and second transparent substrates are made of glass and film having different electrode attachment methods. It is to provide a display device with a tablet that can do the above.

[0010]

SUMMARY OF THE INVENTION A first object of the present invention is to:
A tablet in which a first transparent substrate and a second transparent substrate are stacked, and a first transparent electrode and a second transparent electrode are formed on the facing surfaces of the first transparent substrate and the second transparent substrate, respectively. And a display means configured such that the number of dots in one side direction is smaller than the number of dots in the other side direction orthogonal to the one side direction, and the tablet is placed on the display screen thereof. Is achieved by the first means in which the electrode having poor linearity of the first and second transparent electrodes is aligned with the side direction of the display means having a small number of dots.

The second object of the present invention is achieved by the third means in the first means, wherein the first and second transparent electrodes are composed of resistive films.

A third object of the present invention is that in the first means, the first transparent substrate is made of glass, and the second transparent substrate is made of glass.
The transparent substrate of is achieved by the third means which is composed of a film.

[0013]

In the first means, the side of the display screen of the display device having the smaller number of dots in the direction of one side thereof is aligned with the first or second transparent electrode having the poor linearity. By simply arranging the structure of the conventional tablet called "first transparent electrode direction" and "second transparent electrode direction",
Of the transparent electrode, that is, the amount of deviation between the X direction and the Y direction in the tablet can be averaged, and the tablet can accurately detect the designated coordinates and accurately determine the designated area in the display screen of the display means. Can be determined.

In the second means, the defect of the resistance film can be ameliorated by applying it to the tablet in which the transparent electrode is composed of the resistance film which is likely to cause the variation of the linearity at the time of manufacturing.

In the third means, the first and second
Even if the transparent substrate of is composed of glass and film with different electrode attachment methods, the linearity variation caused by it is made to match the side with poor linearity to the side with the smaller number of dots in the display device, Can be averaged.

[0016]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing an embodiment, and FIG.
FIG. 3 is a perspective view showing a disassembled portion of the tablet.

As shown in FIG. 1, the display device with a tablet according to this embodiment has a transparent tablet 2 arranged on a display screen of a rectangular liquid crystal display panel 1. As shown in FIG. 2, the tablet 2 has a transparent glass 3 as a first transparent substrate on the lower side, that is, the liquid crystal display panel 1 side,
A second transparent substrate, which is a transparent film 4 made of a synthetic resin having flexibility such as polyethylene terephthalate, is arranged on the upper side, that is, on the side that is touched with a fingertip or the like. Common electrodes 5 and 5 are attached to both ends of one side of the transparent glass 3 in the longitudinal direction, and a transparent transparent film (not shown) is provided between the common electrodes 5 and 5 in the same manner as in the conventional example described above. It is filmed by. In addition, the segment electrodes 6 and 6 are provided at both ends of the transparent film 4 orthogonal to the longitudinal direction on one side, that is, both ends in the lateral direction.
Is attached, and a transparent transparent film (not shown) is formed between these segment electrodes 6 and 6 by the same method as the above-mentioned conventional example.

As described above, since the linearity of the resistance film formed on the transparent glass 3 is inferior to that of the resistance film formed on the transparent film 4, the linearity on the transparent film 4 side is ± 0.7%. Assuming that the linearity on the side of the transparent glass 3 is ± 1%, the output error of the tablet 2 when the tablet 2 of 1024 divisions is constructed with this is calculated as follows. That is, on the transparent glass 3 side, 1024 × (1/100) = 10.24≈11. On the other hand, on the transparent film 4 side, 1024 × (7/1000) = 7.168≈8. In this way, the output error becomes large on the transparent glass 3 side even for 3 points. Rounding up after the decimal point is because the tablet can output only integers.

Next, an error was calculated when the tablet 2 was arranged on the liquid crystal display panel 1 having 640 dots on the segment electrode 6 side and 200 dots on the common electrode 5 side. The dots on the liquid crystal display panel 1 have a pitch of 0.36 mm.
That is, the deviation on the segment electrode 6 side is (640/1024)
× 8 = 5 dots (1.8 mm), and the deviation on the common electrode 5 side is (200/1024) × 11 = 2.15≈3 dots (1.08 mm). Therefore, by locating the one with less linearity in the liquid crystal panel 1 with the smaller number of dots, it is possible to average the amount of deviation in the segment electrode 6 direction and the common electrode 5 direction, that is, in the X and Y directions of the tablet. it can. Also in this calculation, the fractional part is rounded up, because the dot shift of the liquid crystal display panel can be only an integer.

On the contrary, the segment electrode 6 is provided on the transparent glass 3 side.
When calculating the deviation when the common electrode 5 is provided on the transparent film 4 side, the deviation on the segment electrode 6 side is (640/1024) × 11 = 6.875≈7 dots (2.52 mm), On the other hand, the deviation on the common electrode 5 side is (200/102
4) × 8 = 1.5625≈2 (0.72 mm). As described above, when the liquid crystal panel 1 having the poorer linearity is positioned at the liquid crystal panel 1 having the larger number of dots, the segment electrode 6 direction and the common electrode 5 direction, that is, the X direction and the Y direction of the tablet are compared with the above-described embodiment. There will be a large difference in the amount of deviation in, and as a result, it will be a cause of erroneous detection.

[0021]

According to the first aspect of the present invention, the configuration of the conventional tablet in which the electrode having the poor linearity is located at the side having a small number of dots of the liquid crystal means can be arranged by a very simple arrangement. The amount of deviation between the first transparent electrode direction and the second transparent electrode direction, that is, the X direction and the Y direction in the tablet can be averaged, and the tablet accurately detects the indicated coordinates, and the display screen of the display means. It is possible to inexpensively provide a display device with a tablet capable of accurately discriminating an instructed area inside.

According to the second aspect of the invention, the defect of the resistance film can be ameliorated by applying it to the tablet in which the transparent electrode is composed of the resistance film in which the linearity variation is likely to occur at the time of manufacturing.

According to the third aspect of the present invention, even when the first and second transparent substrates are made of glass and film having different electrode attachment methods, the variation in linearity caused thereby is averaged. be able to.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention.

FIG. 2 is a perspective view showing only the tablet portion in an exploded manner.

[Explanation of symbols]

 1 liquid crystal display panel 2 tablet 3 transparent glass (first transparent substrate) 4 transparent film (second transparent substrate) 5 common electrode 6 segment electrode

Claims (3)

[Claims] 1. A first transparent substrate and a second transparent substrate are stacked, and a first transparent electrode and a second transparent electrode are provided on opposite surfaces of the first transparent substrate and the second transparent substrate. Each of the formed tablets, and the display means in which the number of dots in one side direction is less than the number of dots in the other side direction orthogonal to the one side direction, and the tablet is placed on the display screen. The tablet-equipped display device according to claim 1, wherein the tablet has an electrode having poor linearity among the first and second transparent electrodes aligned with a side direction having a small number of dots of the display means. 2. The display device with a tablet according to claim 1, wherein the first and second transparent electrodes are composed of resistive films. 3. The display device with a tablet according to claim 1, wherein the first transparent substrate is made of glass, and the second transparent substrate is made of a film.