JPH0725428U - Touch panel - Google Patents

Abstract

(57) [Summary] [Purpose] The spacer is deleted to prevent the deterioration of the image quality due to the refraction and scattering of light at the spacer. [Structure] The insulating transparent second sheet 4 attached to the display surface 2a has a radius of curvature R2 that is substantially the same as that of the display surface 2a.
And the flexible and insulating transparent first sheet 3 is
The radius of curvature R1 is set to be smaller than the radius of curvature R2 of the seat 4. Further, the peripheral members of each sheet are joined by the adhesive 6. By using laminated glass in which thin glass sheets 3b and 3c are bonded to the first sheet 3 with a translucent resin adhesive 3d, the surface is less likely to be scratched, and impact resistance and flexibility can be improved. Further, by enclosing gas between the first and second sheets to prevent the inner surface from being contaminated, the life can be greatly extended.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a touch panel used by being attached to a display surface of a CRT or the like, and particularly eliminates the need for an intermediate spacer.

[0002]

[Prior art]

 As shown in FIG. 2, the touch panel 1 is used by being attached to a display surface 2 a of a CRT (generally a display device) 2 so that coordinate information of a point touched on the panel can be input to an external device. . The touch panel 1 has a transparent and conductive first sheet 3 such as a PET sheet on which a transparent conductive film (including the case of a resistance film) 3a is formed on the inner surface and a transparent inner surface. An insulating transparent second sheet 4 such as a PET sheet or a glass sheet on which the conductive film 4a is formed is integrally held with a transparent spacer 5 so that the inner surfaces thereof face each other closely.

The touch panel 1 is used by sticking the outer surface of the second sheet 4 (the surface opposite to the inner surface on which the transparent conductive film 4a is adhered) onto the display surface 2a which is curved outwardly convex. . When the outer surface of the first sheet 3 is pressed with, for example, a fingertip, the first sheet is dented, and the second sheet 4 and the conductive film are brought into contact with each other, the coordinate information of the contact point is input to the outside as an electric signal. It has become so.

There are various types of touch panels 1, depending on the type, such as one having transparent conductive films 3a and 4a deposited on one surface, one having a row shape and the other having a column shape. As the spacer 5, for example, a granular or rod-shaped one made of plastic or the like having an outer shape of about 1 mm or less is used.

[0005]

[Problems to be solved by the device]

 In the conventional touch panel, there is a problem that the spacer 5 interposed between the first and second sheets 3 and 4 refracts and scatters light to deteriorate the quality of a display image. The present invention intends to provide a touch panel that does not use a spacer in order to solve this problem.

[0006]

[Means for Solving the Problems]

 (1) In the touch panel according to claim 1, the second sheet is formed to have substantially the same radius of curvature as the display surface of the display, and the first sheet is smaller than the radius of curvature of the second sheet. The first and second sheets are formed so as to have a radius of curvature, and the peripheral portions of the first and second sheets are joined together with an adhesive so that no spacer is interposed between the first and second sheets.

(2) According to a second aspect of the invention, in the touch panel according to the first aspect, the first sheet is formed by bonding a plurality of thin glass sheets with a translucent resin adhesive. (3) In the invention of claim 3, in the touch panel according to (1) or (2), gas is sealed between the first sheet and the second sheet.

[0008]

【Example】

 An embodiment of the present invention is shown in FIG. 1 by giving the same reference numerals to the portions corresponding to those in FIG. 2, and the duplicated description will be omitted. In this invention, the second sheet 4 is formed so as to have a radius of curvature R2 which is substantially the same as that of the display surface 2a. On the other hand, the first sheet 3 is formed to have a radius of curvature R1 smaller than the radius of curvature R2 of the second sheet 4. The peripheral edges of these two sheets are joined together by a flexible adhesive 6 around the entire circumference. In the touch panel 1 configured in this way, the radius of curvature of each sheet is R1 <R2, and therefore the gap between both sheets becomes slightly larger as approaching the center line L from the periphery of the sheets. For example, the peripheral portion has a gap of about 0.1 mm and the central portion has a gap of 0.5 to 1 mm. Since the peripheral portions of the first and second sheets are fixed to each other and R1 <R2, and the first sheet 3 is formed in a dome shape on the second sheet 4, there is no spacer between the sheets. Since the first sheet 3 is flexible and the first sheet 3 is flexible, it can be easily depressed by pressing it with a finger, and can be restored by itself when the finger is released.

A PET sheet or a glass sheet can be used as the first sheet 3, but when the glass sheet is used, it is harder to be scratched than the PET sheet because it is hard. However, in order to improve impact resistance and flexibility, thin glass sheets 3b and 3c (generally a plurality of sheets) are used as a translucent resin adhesive (for example, trade name “Dumilan” manufactured by Takeda Chemical Co., Ltd.) as shown in FIG. 1C. It is preferable to use a laminated glass laminated by 3d (claim 2).

It is also possible to hermetically seal the peripheries of the first and second sheets 3 and 4 with a flexible adhesive 6 so that an inert gas or dry air is enclosed between the sheets (claim 3). The pressure Ps of the enclosed gas is set higher than the maximum atmospheric pressure Pa used. The inside of the space surrounded by the first and second sheets does not flow air, so it does not become dirty and does not condense, and the life of the panel can be greatly extended.

[0011]

[Effect of device]

 According to this invention, the first sheet 3 has a smaller radius of curvature than the second sheet 4, the peripheral portion of the first sheet 3 is joined to the peripheral portion of the second sheet 4, and the second sheet 4 is formed into a dome shape with a gap. Therefore, the conventional spacer can be omitted. Therefore, the problem of deterioration of display quality due to refraction and scattering of light by the spacer, which has been a problem in the past, does not occur.

When a laminated glass obtained by laminating a plurality of thin glass sheets with a translucent resin adhesive is used as the first sheet 3, scratches are less likely to occur, and impact resistance and flexibility can be improved. . Further, when gas is sealed between the first and second sheets, the inner surface does not become dirty and the life of the panel can be greatly extended.

[Brief description of drawings]

1A is a sectional view showing an embodiment of the present invention, B is an enlarged sectional view of a P portion of A, and C is a sectional view of a first sheet 3 of A having a laminated glass structure.

FIG. 2A is a cross-sectional view of a conventional touch panel, and B is a cross-sectional view showing a state where the touch panel of A is pressed with a finger.

Claims (3)

[Scope of utility model registration request] 1. A flexible film having a transparent conductive film formed on its inner surface,
An insulative transparent first sheet and an insulative transparent second sheet having a transparent conductive film formed on the inner surface thereof are integrally held with the inner surfaces thereof closely opposed to each other, and the integrally held Attach the outer surface of the second sheet (the surface opposite to the inner surface) onto the display surface (curved outwardly) of the display,
In a touch panel for inputting coordinate information of a point touched on the outer surface of the first sheet to the outside, the second sheet is formed to have substantially the same radius of curvature as the display surface of the display, and the first sheet is And a radius of curvature smaller than the radius of curvature of the second sheet, peripheral portions of the first and second sheets are joined by an adhesive, and a spacer is not interposed between the first and second sheets. A touch panel. 2. The touch panel according to claim 1, wherein
The first sheet is configured by laminating a plurality of thin glass sheets with a translucent resin adhesive. 3. The touch panel according to claim 1 or 2, wherein gas is sealed between the first sheet and the second sheet.