TW201322098A - Electromagnetic induction type touch control device - Google Patents

Abstract

The present invention discloses an electromagnetic induction type touch control device, comprising a touch sensing pad and a signal processing circuit connected to the touch pad. The touch pad allows a user to perform touch operations to make the signal processing circuit generate a control signal. The touch sensing pad is formed by using a non-conductive material as a base coated covered thereon with a material capable of transmitting AC signals. As a result, the present invention can replace a conventional touch structure formed by using an ITO conductive thin film.

Description

Electromagnetic inductive touch device

The present invention relates to a touch device, and more particularly to a touch device that generates a touch signal by using an electromagnetic coupling principle.

The application of touch technology in 3C products is more and more extensive. At present, there are navigation systems in the exhibition area, smart phones, computer game machines, and automated work machines. The main reason is that the touch method has simple operation. Convenient advantages, and no need to prepare additional input controls, anyone can easily get started.

As a touch input technology for detecting a touch position, there are two types of resistive touch and capacitive touch.

Referring to FIG. 9 , the resistive touch device is provided with a ITO glass 202 and an ITO film 203 separated from each other on a display 201 , and a plurality of spacers 204 are disposed between the ITO glass 202 and the ITO film 203 . A voltage of 5 volts is applied between the ITO glass 202 and the ITO film 203. When the user touches the ITO film 203, the recess is brought into contact with the ITO glass 202 to generate a voltage change, and the voltage of the touch point is sensed. Detect the location of the touch point. The analog signal of the voltage change is converted into a digital control signal and input into the display to achieve the purpose of touch. However, the resistive touch technology can only achieve single-point touch, and the touch sensing is less accurate, and the frequent touch and press are likely to cause scratches on the ITO film 203 and the ITO glass 202, resulting in damage.

Referring to FIG. 10, the capacitive touch device has two layers of ITO film 206 on a display 205. The two ITO films 206 are separated by a glass 207, and the outermost layer is a layer of cerium oxide hardened layer 208. A uniform electric field is established on the surface of the glass 207, and the human body touches the static electricity to cause the static electricity to flow into the ground, and the weak current is used to sense the touch position to achieve the purpose of the touch, and the capacitive touch can be used for the resistive touch. The advantage of multi-touch is achieved, and there is no shortage of scratches.

The ITO film used in the conventional touch structure is composed of an oxide of rare element indium. The rare element is not only a rare stock on the earth, but also has difficulty in mining and environmental protection. The use of such rare elements in people's livelihood electronics, such as mobile phones and computers with extremely high replacement rates, is a meaningless and irresponsible waste; if there are other alternatives, it can not only reduce the manufacturing cost of mobile phones and computers. And it can reduce the waste and abuse of the earth's resources.

The present invention achieves the concept of finding an alternative to the existing ITO film process, and is expected to reduce the waste and abuse of the earth's resources. In order to match the particularity of these alternative materials, special electronic circuits are introduced to handle touch signals transmitted through these material interfaces.

The electromagnetic inductive touch device of the present invention comprises: a touch sensing pad comprising a first signal transmitting layer and a protective layer, the protective layer being disposed on the surface of the first signal transmitting layer, the first signal transmitting layer The touch sensing pad generates an induced voltage according to the electromagnetic coupling phenomenon of the human body; at least one signal processing circuit electrically connects the touch sensing pad, receives the induced voltage and outputs a control signal.

Referring to FIG. 1, in the present invention, a touch sensing pad 10 is constructed using a material capable of conducting an alternating current signal, and may be a single layer structure or a double layer structure as the case may be. In the case of a single layer structure, a protective layer 12 is formed on a signal transmission layer 11, and the protective layer 12 may be made of a glass or plastic material. When the invention is applied to a display panel of a mobile phone or a computer or a keyboard/mouse input device, these products are covered with a protective glass or a plastic shell, and the protective glass or plastic shell can be used as the protective layer 12. The material of the signal transmission layer 11 is selected to be an alternating current signal (ie, alternating noise) other than ITO. The experimental materials show that the applicable materials include metal lines, conductive silver glue, conductive aluminum glue, paper (such as coated paper, kraft paper), graphite, soap, advertising pigments, hair, leather, positive/negative photoresist, printing ink. , enamelled metal wire, etc.

Referring to FIG. 2, if the touch sensing pad 10 has a two-layer structure, it can be applied to a two-dimensional array application. The first signal transmission layer 13, the second signal transmission layer 14, and a protective layer 12 are included. When the first signal transmission layer 13 and the second signal transmission layer 14 are metal lines, conductive silver glue or conductive aluminum glue, etc., a continuous flow resistance layer 15 is disposed between the two, so that the first signal transmission layer 13 and the first The two signal transmission layers 14 are insulated and overlapped to avoid direct shorting of the two transfer layers. The protective layer 12 is formed on the surface of the second signal transmission layer 14. The protective layer 12 can also be made of glass or plastic material, and the materials of the first signal transmission layer 13 and the second signal transmission layer 14 are formed as a material capable of conducting an alternating current signal.

Please refer to FIG. 3, which is a block diagram of a circuit according to a first embodiment of the present invention, which is applied to an electronic circuit system using AC power supply. The touch sensing pad 10 is connected to an input terminal of a signal processing circuit 20. The signal processing circuit 20 can be a differential amplifier circuit, such as an operational amplifier or a comparator, and an IC of the model LM358 can be used as the signal processing circuit 20. The AC adapter 30 converts the AC voltage into a DC voltage. Since the power converter 30 uses an AC voltage, such as 110V, 60Hz, the power converter 30 supplies power, and the AC voltage also radiates electromagnetic energy to the surrounding environment. Because the human body has the characteristics of electromagnetic absorption, it will absorb the surrounding power radiation, and the user's body will also absorb the electromagnetic radiation energy, so AC noise will be introduced into the electronic circuit system. When the signal processing circuit 20 passes through the power converter 30, an electromagnetic induction phenomenon occurs, and when the user touches the touch sensor pad 10, an induced voltage is generated on the touch sensor pad 10. The signal processing circuit 20 can generate a control signal, which can be used to control a device to be controlled. The light-emitting diode 40 is taken as an example. When the control signal is output, the light-emitting diode 40 can be driven to be illuminated. Conversely, When the user does not touch the touch sensor pad 10, the light emitting diode 40 is in a non-bright state.

As described above, when the AC signal transmitting layer 11 of the touch sensing pad 10 is tested on coated paper, a paper having a size of 12×0.6 cm is used as a sample, and one end of the wire is used to connect the paper, and the other end of the wire is connected to the signal. In the processing circuit 20, the experimental result shows that when the user touches the coated paper, the signal processing circuit 20 can generate a control signal to illuminate the light-emitting diode 40. When testing in kraft paper, paper having a size of 4 x 0.6 cm is used as a sample, and the light-emitting diode 40 can be smoothly illuminated. The graphite test is carried out using a pencil core for the sample.

Please refer to FIG. 4 , which is a first embodiment of the present invention applied to DC power supply. The foregoing circuit architecture can be integrated into an electronic circuit system inside the electronic device, for example, integrated in a mobile phone or a telephone, and the input end of the signal processing circuit 20 is connected. There are a plurality of touch sensing pads 10, and the signal processing circuit 20 receives a voltage from a DC power source (for example, a battery). If an oscillating circuit is provided in the electronic circuit system, an AC noise (signal) can be generated by the user. When the touch pad 10 is touched, the circuit operates in the same manner as described above, and the user's body can absorb the AC signal generated by the oscillating circuit, so that AC noise is introduced to cause the signal processing circuit 20 to generate a control signal.

Referring to FIG. 5, the second embodiment of the present invention is applied to a DC power supply. The input end of the signal processing circuit 20 is connected to a plurality of touch sensing pads 10, and the signal processing circuit 20 receives a power source (such as a battery) from a DC power source. Voltage, if there is no oscillating circuit in the electronic circuit system, when the user's finger touches the two touch sensing pads 10 at the input end, an equivalent capacitance can be generated between the two touch sensing pads 10. When the equivalent capacitance of the finger occurs, the input equivalent impedance of the signal processing circuit 20 changes, thereby causing a change in its output state, and a control signal can also be generated.

The touch sensing pad 10 can be presented in a one-dimensional arrangement, a two-dimensional cross arrangement, a matrix arrangement, and the like according to actual application conditions. As shown in FIG. 6 , the plurality of touch sensing pads 10 can respectively generate respective control signals, wherein each of the touch sensing pads 10 is elongated and connected to a signal processing circuit 20 to form a single one. Signal channel. When the user touches the different touch sensing pads 10 respectively, the corresponding signal processing circuit 20 can generate a control signal to determine the coordinate position of the touch pressure.

The two-dimensional cross-arrangement shown in FIG. 7 is formed by using the two-layer touch sensing pad 10 as shown in FIG. 2, and the shape thereof can be linear and cross-aligned along the X and Y axes, and the first signal is transmitted. The layer 13 and the second signal transmission layer 14 are respectively used as the sensing lines of the X-axis and the Y-axis, and 16 (4×4) touch points 16 can be provided according to the arrangement of FIG. 7, when any one of the touch points 16 is touched by the user. The corresponding signal processing circuit 20 in the X and Y axis directions can generate a signal, thereby determining the coordinates of the touch point 16.

As shown in FIG. 8, a plurality of touch sensing pads 10 are arranged in a matrix form. Each of the touch sensing pads 10 is an independent touch point and is connected to an independent signal processing circuit 20. The arrangement is suitable for touch. Small mobile handsets with a small number of handles.

10. . . Touch sensor pad

11. . . Signal transmission layer

12. . . The protective layer

13. . . First signal transmission layer

14. . . Second signal transmission layer

15. . . DC blocking layer

16. . . Touch point

20. . . Signal processing circuit

30. . . Power conversion circuit

40. . . Light-emitting diode

FIG. 1 is a schematic structural view of a first embodiment of a touch sensing pad of the present invention.

2 is a schematic structural view of a second embodiment of the touch sensing pad of the present invention.

Figure 3 is a block diagram showing the circuit of the first embodiment of the present invention.

Figure 4 is a block diagram showing the circuit of a second embodiment of the present invention.

Figure 5 is a block diagram showing the circuit of a second embodiment of the present invention.

FIG. 6 is a schematic diagram of the touch device of the present invention arranged in one dimension.

FIG. 7 is a schematic diagram of the touch device of the present invention arranged in two dimensions.

FIG. 8 is a schematic view showing the touch devices of the present invention arranged in a matrix.

FIG. 9 is a schematic structural view of a conventional resistive touch device.

FIG. 10 is a schematic structural view of a conventional capacitive touch device.

10. . . Touch sensor pad

11. . . Signal transmission layer

12. . . The protective layer

Claims (9)

An electromagnetic inductive touch device includes: a touch sensing pad, comprising a first signal transmitting layer and a protective layer, the protective layer is disposed on a surface of the first signal transmitting layer, and the first signal transmitting layer is non- The material of the indium tin oxide is formed by the touch sensing pad according to the electromagnetic coupling phenomenon of the human body; at least one signal processing circuit is electrically connected to the touch sensing pad, receives the induced voltage and outputs a control signal. The touch sensitive pad further includes a second signal transmission layer, and the second signal transmission layer is insulated from the first signal transmission layer, as in the electromagnetic induction touch device of claim 1. The electromagnetic inductive touch device of claim 2, wherein an insulating layer is disposed between the first signal transmission layer and the second signal transmission layer. The electromagnetic induction type touch device according to any one of claims 1 to 3, wherein the signal processing circuit is an operational amplifier. The electromagnetic induction type touch device according to any one of claims 1 to 3, wherein the signal processing circuit is a comparator. The electromagnetic induction type touch device according to any one of claims 1 to 3, wherein the first signal transmission layer of the touch sensor pad is a metal line, a conductive silver paste, a conductive aluminum paste, a paper, a graphite, and a soap. , advertising pigments, hair, leather, positive/negative photoresist, printing ink or enamelled metal wire. The electromagnetic induction type touch device according to claim 2 or 3, wherein the second signal transmission layer of the touch sensor pad is a metal line, a conductive silver paste, a conductive aluminum paste, paper, graphite, soap, and an advertising pigment. , hair, leather, positive/negative photoresist, printing ink or enamelled metal wire. The electromagnetic induction type touch device according to claim 6, wherein the second signal transmission layer of the touch sensor pad is a metal line, a conductive silver paste, a conductive aluminum paste, paper, graphite, soap, an advertising pigment, and a hair. , leather, positive/negative photoresist, printing ink or enamelled metal wire. The electromagnetic inductive touch device according to any one of claims 1 to 3, wherein the protective layer is a glass layer or a plastic layer.