JPS59149537A - Touch screen - Google Patents

Abstract

PURPOSE:To eliminate the misrecognition of a coordinate value due to the variance of voltage and at the same time to attain a simultaneous output of plural areas, by deciding a touch position from the frequency. CONSTITUTION:When a touch is given to an electrically conductive thin film 3 with a finger, the film 3 has a contact with a conduction line 2 at the touch area. Then an alternating current of either frequency is flowed to a frequency analyzer 5 from an AC voltage source 4. The value of the frequency of the alternating current is analyzed by the analyzer 5. Thus the analyzer 5 decides the touch area of the film 3 through a position decider 6 to which said frequency is fed. When plural points are touched at a time, the analyzer 5 can detect plural frequencies. Thus a touch screen can display the positions of plural points.

Description

[Detailed description of the invention] Technical field of invention 1 The present invention relates to touch screens.

[Technical Background of the Invention] Conventionally, various characters, numbers, etc. displayed on a CRT, for example,
For example, a light pen is often used as a means for humans to look at figures, arrows, etc. and think about them, and to transmit the results to a computer via a CRT.

In recent years, a transparent coordinate input device has been developed in which a touch screen, in which a human finger plays the role of a light pen, is attached to the entire surface of a CRT. This touch screen consists of two conductive thin films that do not come into contact unless touched, with a gap of only 1.7 sq. It is constructed by passing a current to generate a potential corresponding to a position in the X direction, and then passing a parallel current in the Y direction (vertical direction) to form a potential corresponding to a position in the Y direction.

In such conventional touch screens, when a person touches the touch screen with a finger, another conductive thin film comes into contact with one point, and at this time, X, X,
Coordinate input is performed by reading the potential in the Y direction.

[Problems with the Background Art] However, in such conventional tap screens, if the touch pressure is weak, the potential of the touch point is not reflected correctly on the conductive thin film due to poor contact, and coordinate values unrelated to the touch point are may be recognized.

Also, if multiple distant points are touched at the same time,
The problem is that multiple coordinate points are not read, but only one point corresponding to an intermediate point is read.

[Object of the invention] The present invention has been made in response to such conventional circumstances.
The aim is to provide a touch screen that can read multiple coordinate points regardless of touch pressure.

[Summary of the Invention] In other words, the present invention comprises a plurality of conductive wires disposed on a non-conductive film surface, and a conductive wire arranged at minute intervals from the conductive wires and covering the entire surface of these conductive wires. An AC voltage source that applies AC voltages of different frequencies to a covering conductive thin film and the conductive wire, respectively, and the frequency of the AC voltage that conducts the conductive VJ film by pressing the conductive thin film in the direction of the conductive wire. This touch screen is characterized by comprising a frequency analyzer that detects the frequency, and a position determiner that inputs the frequency detected by the frequency analyzer and determines the suppressed portion of the conductive thin film.

[Embodiment 1 of the Invention] The details of the present invention will be described below with reference to an embodiment shown in the drawings.

FIG. 1 shows a touch screen according to an embodiment of the present invention. In the figure, reference numeral 1 indicates a non-conductive film surface of a thin film made of glass, for example. A large number of thin film conductive wires 2 are disposed in a sash-like manner in the vertical direction (Y direction). On the front surface of the conductive wire 2, conductive thin films 3 are disposed at small intervals. The insulation between the conductive thin film 3 and the conductive wire 2 can be achieved by a conventional method in which, for example, minute insulators are placed between the conductive thin film 3 and the conductive wire 2 in the form of dots. . An AC voltage source 4 is connected to each conductive wire 2,
AC voltages (f + , f 2 . . . f) of different frequencies are applied to each conductive wire 2 by this AC voltage source 4 . This AC voltage source 4 is connected to a frequency analyzer 5 and
The conductive thin film 3 is also connected to a frequency analyzer 5. Further, the frequency analyzer 5 includes a frequency analyzer 5r:
Manually input the detected frequency and press U based on this frequency.
A position determiner 6 for determining the T1 portion is connected.

That is, the touch screen C configured as above
When the conductive thin film 3 is touched with a finger, the conductive thin film 3 at the touched portion comes into contact with the conductive wire 2, and an alternating current of any frequency from the alternating current voltage source 4 flows through the frequency analyzer 5. The value of the frequency of this alternating current is determined by the frequency analyzer 5.
The position determination unit 6 inputting this frequency from the frequency analyzer 5 determines the touched part of the conductive thin film 3.

In addition, with the touch screen C configured in this way, the wave number analyzer 5 can detect multiple frequencies even when multiple points are touched at the same time. -It is possible.

FIG. 2 shows another embodiment of the present invention, and in this embodiment C, the position of the touch screen in the downward direction (Y direction) is determined.

However, in this embodiment C, a large number of conductive wires are arranged along the left-right direction (X direction) at regular intervals on the front surface of the non-conductive film surface 1. The location can be detected. Other than this, the structure is similar to that of the embodiment described in FIG. 1, so the same parts are denoted by the same reference numerals and the explanation thereof will be omitted.

FIG. 3 shows yet another embodiment of the present invention, in which this touch screen can detect positions in both the Xlj direction and the Y direction.

That is, this touch screen is
It is constructed by combining the touch screens shown in the figure, and in the upper layer of the figure, a non-conductive film surface 1a, a conductive wire 2a, and a conductive thin film 3a for detecting the position in the X direction are arranged in order from the bottom. 83, in the upper layer of the figure, a non-conductive film surface 1b for Y-direction position detection, a conductive line 2b, and a conductive thin film 3b are disposed in order from the bottom.Therefore, the conductive film 3b is arranged from above. By pressing, the position in the X and Y directions can be detected in the same manner as described in FIGS. 1 and 2.

That is, as shown in FIG.
The A device in the Y direction is detected via the frequency analyzer 5b and the position determiner 6b which detect the position in the Y direction, and these signals are input to the coordinate determiner 7, respectively. , this coordinate determiner 7 determines the coordinates on the plane.

[Effects of the Invention] As described above, according to the touch screen of the present invention,
Since the touch position is determined by frequency, it is possible to eliminate misrecognition of coordinate values due to voltage fluctuations. Furthermore, since multiple points can be touched at once ('), outputs from multiple points can be obtained, making simultaneous touching possible and dramatically increasing the selection range of operating points.

That is, for example, if you set N operation points on a touch screen, only N selection points can be obtained in the case of a conventional single touch, but by making a two-point touch, for example, N selection points can be obtained.
(If-1) point selection points can be obtained.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing a touch screen according to one embodiment of the present invention, FIG. 2 is an explanatory diagram showing another embodiment of the touch screen according to the present invention, and FIG. 3 is an explanatory diagram showing another embodiment of the touch screen according to the present invention. FIG. 4 is a cross-sectional view without showing an embodiment, and FIG. 4 is a block diagram showing a signal processing system of the touch screen shown in FIG. 3. 1...Non-conductive film surface 2...
...... Conductive wire 3... Conductive thin film 4...
...... AC voltage source 5 ...... Frequency analyzer 6 ...... Position determiner 7.
・・・・・・・・・Coordinate determiner representative patent attorney
Satoshi Suyama - Figure 1 Figure 4

Claims (1)

[Claims] (1) A plurality of conductive wires arranged on a non-conductive film surface,
a conductive thin film disposed at a minute interval from these conductive wires and covering the entire surface of these conductive wires; an AC voltage source that applies alternating current voltages of different frequencies to the conductive wires; A frequency analyzer detects the frequency of the alternating current voltage that conducts through the conductive thin film by suppressing it in the direction of the conductive line, and the frequency detected by this frequency analyzer is input to determine the suppressed portion of the conductive thin film. A touch screen characterized by comprising a position determination device.