JPS6230450B2 - - Google Patents

Description

[Detailed Description of the Invention] There are two methods for inputting handwritten characters and figures into a computer: one is to optically read and input the written characters and figures, and the other is to input the letters and figures while they are being written. A method of inputting the position coordinates of a writing point every moment is known, and the present invention relates to a character and graphic input device used for the latter method.

It has been a while since the capacitively coupled data tablet was developed by the Rand Corporation in the United States. It consists of three parts: a tablet part for determining the coordinates within the computer, and a code conversion part for encoding the coordinates.

In this device, quantization of the coordinates of the stylus is performed by determining the number of electrodes in each of the x- and y-axis directions depending on the required resolution. Each intersection point formed by each electrode line group in the x-axis direction and the electrode line group in the y-axis direction is a coordinate point of this tablet. The tablet consists of a group of electrode wires forming the x-axis or y-axis, a terminal section that receives time-series driving signals, and a code that receives signals from the terminal section and sends the signals to the electrode wires of the x-axis or y-axis appropriately. conversion part,
It consists of a printed circuit board in which each electrode group, terminal, etc. for the x-axis or y-axis is embedded, and the printed circuit board that makes up the x-axis and the printed circuit board that makes up the y-axis are usually the same shape, and one side is set at 90 degrees. The circuits are rotated and stacked one on top of the other, and the code conversion portion and the terminal portion of each electrode wire group in one of the printed circuits are electrostatically coupled to the terminals of each electrode wire group and the code conversion portion in the other printed circuit, respectively. , when superimposed on both printed circuits, when the stylus is brought close to each coordinate point, due to capacitive coupling, if there is a drive signal on the x-axis electrode line or at the same time on the y-axis electrode line, the stylus will receive the signal. is configured to receive. FIG. 1 conceptually shows how a driving signal is sent to the tablet using this electrostatic coupling, code conversion, etc., and FIG. 2 conceptually shows the use of a stylus.

t ₁ , t ₂ , t ₃ , t ₄ , t ₅ , t ₆ represent drive signals in time series, and when one of them, for example t ₁ , is being driven, the other signals are not sent out. y _{1 ......} y ₈ and (x ₁ ...... ing. When the tablet is configured with 8 electrode lines on the x-axis and 8 electrode lines on the y-axis as in this example, the code conversion part is surrounded by double squares and squares, and the code conversion electrodes are connected to the drive signal. electrically connected.
On the lower side (another printed circuit board) corresponding to the code conversion section, there is a group of terminals connected to the matrix electrodes, which are electrostatically coupled. Now, when a drive signal is sent to the y-axis electrode line from _t1 , _y5 ,
Each electrode wire of y ₆ , y ₇ , y ₈ has a positive potential, and y ₁ ,
Each of the electrode lines y ₂ , y ₃ , and y ₄ has a negative potential. t ₁
disappears and t ₂ is driven, y ₃ , y ₄ , y ₅ , and y ₆ become positive potentials, and y ₁ , y ₂ , y ₇ , and y ₈ become negative potentials. Subsequently, when t ₃ is driven, y ₂ , y ₃ , y ₆ , y ₇
has a positive potential, and y ₁ , y ₄ , y ₅ , and y ₈ have a negative potential. If plus is set to 1 and minus is set to 0, binary codes from y ₁ to y ₈ are obtained as shown. Next, another similar printed circuit (for the x-axis)
A similar binary code can be obtained by sending driving signals t ₄ , t ₅ , and t ₆ . As is clear from the arranged symbols _{in FIG .}
When we look at y ₅ , we find that it differs from y ₄ and y ₆ in only one of the three digit codes, and if the stylus is in the middle of the electrode wires, the error will be minimized no matter which signal is received. (This is called the Gray code). Since the coordinate position of the x-axis can be determined by t ₅ and t ₆ below t ₄ ,
For example, if the stylus is located at the positions y ₄ and x ₅ as shown in Figure 2, the stylus receives the input code (010110) corresponding to y ₄ and x ₅ due to the electrostatic coupling with these electrode lines. This is then transmitted to the processing circuit.

As mentioned above, by the capacitive coupling method,
Although it is possible to input characters, figures, etc. into a computer, the stylus requires a signal line to send the detection signal to the processing circuit because the drive signal for the electrode wire is detected by capacitive coupling using a stylus. be. This signal line is an extremely large hindrance to operability when writing characters or figures, and if the electrode and stylus approach within a certain distance, the tablet surface and stylus will come into contact due to electrostatic coupling. The signal is received even when the tablet surface is not in use, and as a result, the start and end of strokes of characters and figures cannot be detected accurately. A switch is added that turns on when touched. This addition of parts makes it difficult to write letters and figures on the tablet surface, increases the number of parts, and reduces reliability. Furthermore, the aforementioned devices require a special stylus, which precludes the use of conventional writing instruments (pencils, ballpoint pens). For this reason, it is not possible to place a piece of paper on the tablet surface, write on it, and then leave the paper as a hard copy. This is not suitable for purposes such as creating a slip or the like and using it as input.

The present invention is configured so that the identification signal can be taken out from the circuit board itself without the need to take out the identification code from the stylus by interposing pressurized conductive rubber between the circuit boards forming the x-axis and the y-axis. To provide a tablet board for a character/graphic input device that does not require the use of a special stylus as described above.

The present invention will be explained below with reference to embodiments shown in the drawings. FIG. 4 is an exploded perspective view of the tablet board of the character/graphic input device according to the present invention, and FIG.
-S' is a cross-sectional view of the tablet plate.

As shown in Fig. 4, a circuit board consisting of a group of electrode wires 1A in which many electrode wires are arranged in parallel, a code converter section 1B', etc. is placed on the top to form a Y surface, and a back surface is placed on the bottom, in the vertical direction of the front surface. is the opposite, but the X plane having the same structure as the Y plane is turned 90 degrees from the Y plane and laminated. Figure 3 shows the cross section,
1A indicates an electrode line group, and 1B and 1B' are code conversion parts. Each of the above parts has a laminated structure, and the electrode wire group 1A has an insulating layer 1.
1a, shield metal layer 1.2, insulating layer 1.1
a, electrode wire group layer 1.3a, pressurized conductive rubber layer 1.
4. It is formed of an electrode wire group layer 1.3a, an insulating layer 1.1a, a shielding metal layer 1.2, and an insulating layer 1.1a. Code conversion part 1B is insulating layer 1.1
b, an electrode wire layer 1.3b, an insulating layer 1.1b, an electrode wire layer 1.3b, etc. For the electrode line group layer, the value determined by the required resolution is determined, and the required number is arranged at a predetermined interval, but the direction of the electrode line group on the Y plane and the direction of the electrode line group on the lower X plane are perpendicular directions. The electrode lines are lined up, and the intersection of the electrode lines corresponds to the coordinate point on the tablet. Each of the electrode wire groups is extended beyond the tablet constituting surface, and at one end of each electrode wire group, an electrostatic coupling portion is formed between each of the electrode wires arranged separately via an insulating layer in accordance with a predetermined code to be described later. Conversion sections 1B and 1B', a signal injection terminal T, and a signal extraction terminal R are formed.
Further, as described above, a pressurized conductive rubber layer is interposed between the electrode wire group layers on the X plane and the Y plane. The signal that drives the electrode is sent to the injection terminal T of the code converter 1B on the X plane.
The signal for detecting the position coordinates is extracted from the signal extraction terminal R of the code conversion section 1B'.
Note that the shielding metal layer may be formed by metal vapor deposition on an insulating layer, and the shielding metal layer, insulating layer, and pressurized conductive rubber layer must have elasticity with respect to the stylus.

As an example, the operation will be explained assuming that the number of electrode lines on both the X plane and the Y plane is seven. As shown in FIG. 5, drive signals are sequentially injected from the signal injection terminal T to X ₀ , X ₁ , and X ₂ . As described above, Gray code conversion is suitable for the code conversion section. Drive signal injection electrode wire 1 in code converter 1B.
3d and electrode wire _1.3b , which is an extension of electrode wire 1.3a forming x ₀ to x ₀ ~ from the signal injection electrode wire 1, 3d side
Electrostatic coupling is established between the electrode wire 1.3a forming x ₆ and the electrode wire 1.3b connected thereto so that the electrode wire 1.3a is energized. An example of this is shown in Figure 6, where electrodes p are made of a metal film or piece of metal on one or both sides of the insulating layer at the crossing points of the electrode lines where coupling is required.
This forms a capacitor for coupling.
From the X-plane terminal T, as shown in Figures 5 and 7 _,
When a drive signal is injected into , the electrode lines x ₀ , x ₁ , x ₄ , and x ₅ are driven. When a signal is injected into X ₁ , x ₁ , x ₂ ,
The electrode lines x ₃ and x ₄ are driven, and when a signal is injected into X ₂ , x ₃ , x ₄ , x ₅ , and x ₆ are driven. Regarding the Y plane, in the situation shown in Figure 8, y ₀ to _{y 6}
The capacitive coupling between Y ₀ and _{Y 2} is removed and a signal is output to Y ₀ when y ₀ or y ₁ or y ₄ or y ₅ is driven, and a signal is output to Y _1. is when y ₁ or y ₂ or y ₃ or y ₄ is driven, and the signal is output to Y ₂ when y ₃ or y ₄ or
When y ₅ or y ₆ is driven, the signal appears at each signal extraction terminal.

For example, if the coordinates of the stylus are (x ₂ , y ₃ ), if you press the tablet with the stylus at this position, the pressurized conductive rubber layer will lower its resistance and become conductive. , the specific electrode lines of the X plane and the Y plane that are in contact with that position are combined. As understood from Figures 7 and 8, the x ₂ electrode wire is
Y3, which is driven only by _X1 and is in conduction with it in this driven state, is capacitively coupled to _Y1 and _Y2 , so when driven by _X1 , _it is connected to the extraction terminal R. The signals that appear are Y ₀ = 0, Y ₁ = X ₁ , Y ₂
= X ₁ , and when drive signals are sent in _{time series from X 0 , X 1 , and}
By receiving this information, the coordinate position determined by the stylus can be known.

As can be understood from the above explanation, the present invention allows characters and figures to be input without using a special stylus, and can be expected to have extremely great practical effects.

[Brief explanation of the drawing]

FIG. 1 conceptually shows a conventional capacitively coupled tablet, and FIG. 2 conceptually shows the use of a stylus. Figures 3 and 4
The figure shows one embodiment of the present invention, and 1A
is an electrode wire group, 1.1a is an insulating layer, 1.2 is a metal shield layer, 1.3a is an electrode wire group layer, 1.4 is a pressurized conductive rubber layer, 1B and 1B' are code conversion parts, 1 ．．
1b is an insulating layer, 1.3b is an electrode line layer, 1.3d is an electrode line for driving signal injection, T is a signal injection terminal, and R is a signal extraction terminal. Further, FIG. 5 shows the drive signal, FIG. 6 shows an example of electrostatic coupling, and FIGS. 7 and 8 show the connection of the code conversion section.

Claims (1)

[Claims] 1. A first laminated part consisting of an insulating layer, a shielding metal layer, an insulating layer, and a group of electrode wires arranged in parallel, and a second layer consisting of a group of electrode wires arranged in parallel, an insulating layer, a shielding metal layer, and an insulating layer. A laminated portion of the electrode wire groups is arranged so that the electrode wire groups are orthogonal to each other, and a pressurized conductive rubber layer is inserted between the electrode wire groups and laminated, and an extension portion of each of the electrode wire groups is laminated. 1. A tablet for a character/figure input device, characterized in that a code converter is provided by electrostatic coupling between the code converter and a separately arranged electrode wire.