JPH0384615A - Touch panel device - Google Patents

Abstract

PURPOSE:To prevent the occurrence of a Newton ring by applying a reinforcing plate to one of both sides of a touch panel via a dot-shaped spacer. CONSTITUTION:A flexible touch panel 8 made of two transparent conductive films 1 is backed with a transparent plastic plate 4 for reinforcement with use of minute dot spacers 3. As a result, the minute gaps are produced when the film 1 having a smooth surface is put close to the plate 4 having a smooth surface. Thus the Newton rings are produced to deteriorate the transmissibility of the transparent panel 8. In this respect, th spacers 3 having the height of several tens of mum are previously provided. Thus the occurrence of the Newton rings can be prevented.

Description

[Detailed Description of the Invention] [Summary] Regarding the structure of a touch panel device, the purpose is to prevent Newton's rings from occurring even if a plastic reinforcing plate is attached to a touch panel composed of two transparent conductive films. The touch panel is made up of two transparent conductive films stacked one on top of the other, and a reinforcing plate is brought into contact with one surface of the touch panel via a dot-shaped spacer.

[Industrial application field]

The present invention relates to a touch panel device, and more particularly to a touch panel device in which Newton's rings do not occur even when a reinforcing transparent plastic is laminated to a touch panel device made of a transparent conductive film.

In recent years, with the advancement of information processing devices, input/output devices used for exchanging information between humans and machines have become widespread.

For inputting information, a keyboard with an array of key switches is often used, while for outputting information, CR
Display devices based on cathode ray tubes (T) are often used.

However, recently, in order to make it easier for an unspecified number of so-called amateur users to use it, a transparent manual device has been integrated on top of a display device, and necessary items can be displayed on the display device. So-called item display manual devices, in which items are displayed and human input is performed using an input device while looking at the display, are becoming popular.

In such devices, for example, bank terminals, a so-called touch manual input method is used, in which input is performed by directly touching the surface of the input device with a finger.

A touch-type human-powered device is also called a touch panel device, and has a feature that a touch sensor portion corresponding to a key switch of a keyboard can be configured transparently.

Therefore, touch panel devices such as CRT and LCD
(liquid crystal display), FDP (gas discharge display), etc., or stacked on top of a medium on which something is drawn to form an integrated structure, and the necessary items depending on the display device, etc. Information is displayed on the screen, and while viewing through the transparent touch panel device, users can select and touch the desired content with their fingers to read information manually. In other words, one device can simultaneously input and output (display) information.

With the popularization of information, such item display input devices are becoming increasingly popular as simple input/output terminal devices that anyone can use.As a human-powered device that is integrated with such a display device, Touch panel devices are attracting the most attention.

[Conventional technology]

FIG. 2 is a diagram showing an example of how the touch panel device is used.

In the figure, the touch panel device 10 is, for example, a CRT.
It is often used as an integrated structure in close contact with a display device 11 such as a display device 11.

Currently, the display device 11 is difficult to handle because of its curved display surface, but because of its good display performance and low cost, CRTs are often used, but LCDs, which have a flat display surface and are called flat displays, and PDPs are also beginning to be used.

On the other hand, the touch panel device 10 includes, for example, a transparent conductive film made of relatively heat-resistant and transparent polyester, which is provided with a well-known transparent conductive film of ITO (indium oxide/tin oxide). Alternatively, there is a structure in which a transparent conductive film and transparent conductive glass provided with a transparent conductive film of ITO are stacked.

First, a matrix method is well known in which a transparent conductive film 1 in which a transparent conductive film is provided in a striped manner and a transparent conductive glass 6 are overlapped in a crossed manner, and the position is read from the presence or absence of conduction at the position pressed with a finger. There is. This method is a digital position detection method because the resolution is determined by the pitch of the striped matrix.

On the other hand, there is a method in which the transparent conductive film is a transparent resistive film, the transparent resistive film and the transparent resistive glass are overlapped, and the position is read from the change in electrical resistance at the position pressed with a finger. Depending on how it is made, this method can have a very small detection resolution, and is an analog method of position detection.

Alternatively, when pressed with a finger, the gap between the superimposed transparent conductive film l and the transparent conductive glass 6 changes, so
There is also a method that reads the position as a change in capacitance, or detects the capacitance of the human body when it is touched with a finger and reads the position.

Furthermore, a light emitting element and a light receiving element are arranged on two opposing sides of the touch panel device 10, and the position can be read by blocking the light with a finger or the like, or magnetostrictive wires can be stretched across each other to detect the position when the finger touches the device. There are also methods that read the position from changes in magnetostriction.

Among these various methods, the resolution is comparable to the contact area of a human finger, and the structure is simple. The mainstream is a matrix electrode system in which shaped electrodes are stacked orthogonally.

FIG. 4 is a cross-sectional view of a conventional touch panel device.

The figure shows the case of a matrix type touch panel device.
6 is a transparent conductive film made of a polyester film such as polyethylene terephthalate, provided with a striped electrode 5a of a transparent conductive film, and 6 is a transparent conductive glass provided with a striped electrode 5c of a transparent conductive film.

When the transparent conductive film 1 and the transparent conductive glass 6 are overlaid so that the striped electrodes 5a and 50 are perpendicular to each other, and the peripheral portions are adhered with an adhesive 7, a so-called touch panel 8 is completed.

Then, in the gap between the transparent conductive film l and the transparent conductive glass 6, for example, the size of the transparent conductive glass 6 is 20 mm.
A fine spacer 12 with a diameter of 0 μm and a height of 25 μm is
They were provided at intervals of about mm. The spacer 12 is arranged by printing, for example, an ultraviolet curable acrylic resin by screen printing, and maintains the distance between the transparent conductive film l and the transparent conductive glass 6.

By the way, the basic operation of a touch panel device is to touch or press with a finger, or depending on the method, a gloved finger. Therefore, the surface of the touch panel device is inevitably subjected to constant impact even during normal usage. In addition, it is difficult to prevent a large number of unspecified users from touching the touch panel device with hard objects other than their fingers, and if the surface of the touch panel device is scratched, damage may occur.

For example, if an ITO film is provided on a transparent plastic plate such as acrylic resin or polycarbonate and put into practical use, it can be used in place of glass. However, currently, as a second-best solution, a touch panel has been developed that has a structure made of transparent conductive films layered on top of each other, and transparent plastic plates are pasted together to strengthen the soft and flimsy body.

[Problem to be solved by the invention]

As mentioned above, the item display input device, which has an integrated structure of a display device that displays information and a touch panel that inputs information with your finger, is used as an information input/output terminal device for the general public in all kinds of daily life. It is becoming popular.

However, since the basic operation of a touch panel device is to touch it mechanically, breakage of the glass due to this is unavoidable.

Therefore, touch panels that have a structure in which transparent conductive films are stacked on top of each other, and a transparent plastic plate is pasted together to strengthen the weak back of the user's backs, are attracting attention.

However, in the construction of a touch panel, when the smooth surfaces of a transparent conductive film and a transparent plastic reinforcing plate are pasted together, air bubbles will enter the adhered surface, so it is necessary to close them closely to avoid uneven gaps. is extremely difficult. And if the adhesion of the adhered surface is uneven,
Fine gaps are created between the transparent conductive film and the transparent plastic reinforcing plate, resulting in the formation of Newton rings.

FIG. 3 is an explanatory diagram of Newton's rings that occur when the closeness is uneven.

In the figure, 4 is a plastic reinforcing plate, 8 is a touch panel, and the relationship between the poor contact between the reinforcing plate 4 and the touch panel 8 and the Newton ring 9 is schematically shown.

According to the JIS standard, Newton's ring 9 is described as a concentric circle of equal thickness interference that appears near the contact area of two spherical surfaces with different radii of curvature, and if the two contact areas are not spherical, the shape Interference fringes of various shapes appear depending on the

This Newton's ring 9 forms a rainbow-colored interference stripe against disturbance natural light, and as shown in FIG. 2, there is a problem in that it becomes difficult to see the display screen of the display device 11 on which the touch panel device W10 is superimposed, for example.

On the other hand, the interference of Newton's ring 9 also causes moiré, especially when the display device 11 is a raster scan CRT display device.

According to the JIS standard, moire is described as a rough pattern caused by the overlapping of two regularly changing patterns, and moire also occurs when the screen displayed on the display device 11 is viewed through the touch panel 8. There was a problem that caused the problem.

[Means to solve the problem]

This problem is solved by a touch panel device configured such that a reinforcing plate is brought into contact with one surface of the touch panel via a dot-shaped spacer.

[For production]

In the present invention, when a flexible touch panel made of two transparent conductive films is backed and reinforced with a transparent plastic plate, they are overlapped with a fine dot-shaped spacer in between.

In other words, when a film with a smooth surface and a plastic plate with a smooth surface are brought into close contact with each other, it is unavoidable that minute voids will form in the gap, which causes Newton rings. Although the transparency of the transparent touch panel is impaired, in the present invention, a spacer with a height of several tens of micrometers is interposed in advance in the gap.

By doing so, it is possible to prevent the formation of minute gaps that would cause Newton's rings, and therefore it is possible to prevent the formation of Newton's rings.

〔Example〕

FIG. 1 is a detailed explanatory diagram of the present invention.

In the same figure, two transparent conductive films l are made of ITO.
A 120 μm thick polyethylene terephthalate film coated with a membrane was used. Then, striped electrodes 5a and 5b having a pattern width of 3 mm and a pitch of 5 mm were provided on each transparent conductive film 1 by etching.

On the other hand, a spacer 12 formed by printing an ultraviolet curing acrylic resin using a silk screen printing method was provided in the gap between the striped electrodes 5b. The spacers 12 had a thickness of 200 μmφ, a height of 20 μm, and were arranged at intervals of 5 mm vertically and horizontally. The two transparent conductive films 1 processed in this way were overlapped so that the striped electrodes 5a and 5b were perpendicular to each other, and the periphery was fixed with an adhesive 7 to obtain a touch panel 8.

Next, spacers 3 with a size of 200 umφ and a height of 30 μm were placed on a polycarbonate plate with a thickness of 2 mm at intervals of 5 vertically and horizontally by printing an ultraviolet curable acrylic resin using a silk screen printing method. A reinforcing plate 4 was created.

The touch panel 8 was placed on the reinforcing plate 4, and the spacers 3 were positioned between the spacers 12 provided on the touch panel 8, and the periphery was fixed with the adhesive 7.

In the thus manufactured touch panel 8 with the reinforcing plate 4 of the present invention, since the spacer 3 separates the transparent conductive film l and the reinforcing plate 4, it was confirmed that Newton's rings did not occur at all.

In this example, a polyethylene terephthalate film with an ITO film was used as the transparent conductive film, and a polycarbonate plate was used as the reinforcing plate, but various modifications can be made to the material, thickness, etc.

Next, the spacers were formed using an ultraviolet curable resin using a silk screen printing method, but room temperature curable resins or photoresists can also be used, and various modifications can be made to the dimensions and arrangement of the spacers. is possible.

〔Effect of the invention〕

As described above, according to the present invention, a touch panel is constructed using two transparent conductive films, and the stiffness of the panel is compensated for by fixing a plastic reinforcing plate. By arranging a spacer between the touch panel and the reinforcing plate, it is possible to prevent Newton's rings from occurring.

In this way, it is possible to completely eliminate the damage that sometimes occurs in the case of a conventional touch panel constructed by combining a transparent conductive film and a transparent conductive glass. Furthermore, by combining a touch panel made of transparent conductive films with a plastic reinforcing plate, it is expected that the touch panel can be applied not only to flat surfaces but also to various shapes.

Therefore, the present invention greatly contributes to further expanding the field of application of touch panels.

4,

[Brief explanation of drawings]

FIG. 4 is a cross-sectional view of the configuration of a conventional touch panel device. 3.12 is a spacer, and 5a and 5b are striped electrodes. 4 is a reinforcing plate, 7 is an adhesive, and a monthly number for an example of non-invention.
E]

Claims (1)

[Claims] A touch panel (2) configured by overlapping two transparent conductive films (1), wherein a dot-shaped spacer (3) is provided on one surface of the touch panel (2). A touch panel device characterized in that a reinforcing plate (4) is brought into contact with the reinforcing plate (4).