JPS6136828A - Tablet type input device - Google Patents

Abstract

PURPOSE:To detect a selected point by setting the drive and detection lines orthogonal to each other with correspondence secured between each intersecting point and each character or mark and providing a magnetic matter at the tip of a selection pen to make use of a fact that the magnetic field produced from the drive line is disturbed with approximation of the selection pen. CONSTITUTION:A magnetic matter 8c is provided at the tip of a selection pen 8 and usually covered by a cylinder 8d. When the matter 8c is pressed to the board surface of a tablet type input device, a coil spring 8e is compressed. Thus the matter 8c has a contact with the board surface. The drive lines D1-Dn and detection lines S1-Sn are set orthogonal to each other on the board surface, and a sheet where the characters and marks to be selected are printed covers over those drive and selection lines. A magnetic field is generated when a current is flowed to the drive lines, and the detection lines produce nothing since said magnetic field does not cross the detection lines. This magnetic field is disturbed at a point where the matter 8c exists. This produces an induced current to the detection lines. Thus a segment selected by the pen 8 can be detected.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a tablet type input device used as a character/symbol code input device in a Japanese document processing system such as a word processor.

[Technical background of the invention and its problems] Tablet-type input devices have been known as input devices for character/symbol codes in Japanese document processing systems such as word processors.

Tablet-type input devices are configured to specify an input code by touching or pressing a dedicated selection pen to characters and symbols printed on a sheet on the top of the tablet. Electrostatic coupling type etc. are known.

The photoelectric type is a method in which a light-emitting part is provided on either the selection pen or the tablet, and a light-detecting part is provided on the other to detect a match between the two, thereby identifying the segment corresponding to the desired character or symbol. The electromagnetic induction method is a method in which a circuit that generates a fluctuating magnetic field is provided on the selection pen side, a detection line is provided on the tablet side, and a segment is specified by detecting the induced current generated in the detection line. The capacitive coupling method is a method in which a selection pen is brought close to an electrode plate provided on the tablet side to which a pulse is applied, and a segment is identified by detecting the pulse applied to the electrode through capacitor coupling.

However, in the conventional tablet input devices using the above-mentioned methods, it is necessary to provide the selection pen with a light emitting part or a variable magnetic field generation part, or to configure a closed circuit between the circuit inside the tablet and the selection pen. Therefore, in both cases, a signal line was connected to the selection pen, which hindered operation.

In the case of a photoelectric type, it is conceivable to provide a battery-powered light emitting part inside the selection pen in order to eliminate the signal line, but configuring the circuit on the selection pen side in this way would make the selection pen larger and heavier. However, there is still a problem in that the operability deteriorates.

[Object of the Invention] The present invention has been made to solve the problems of the conventional tablet type input device, and the signal line between the tablet and the selection pen is omitted, and the selection pen becomes large. The purpose is to provide a tablet-type input device that is not heavy and has good operability.

[Summary of the Invention] In other words, the tablet input device of the present invention includes drive lines arranged in parallel in a plurality of rows, detection lines arranged in a plurality of rows adjacent to and perpendicular to the drive lines, and a drive line control means for sequentially applying a pulse current to a line; a selection pen having a magnetic body at its tip and selecting an orthogonal point between the drive line and a detection line by bringing the magnetic body close to the drive line; It is characterized by comprising a determination means for determining the orthogonal point selected by the selection pen by detecting a drive line driven by the control means and a detection line in which an induced current is generated due to the approach of the magnetic body. There is.

[Embodiments of the Invention] Details of the present invention will be described below with reference to embodiments shown in the drawings.

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention.

In the figure, D1 to Dn are loop-shaped drive lines arranged in parallel in multiple rows, and 81 to S are drive lines D1 to Dn.
It shows loop-shaped detection lines arranged in multiple rows close to and orthogonal to D.

1 is a drive line control circuit that sequentially applies a pulse current to drive lines D1 to D; 2 is a detection line S1 to S;
3 is a scanning signal generation circuit that outputs scanning pulses to the drive line control circuit 1 and the detection line control circuit 2; 4 is a detection line control circuit 8;
Line control circuit 2 that detects the induced current generated in 1 to SIl
5 is a comparison circuit that performs threshold value discrimination of the output of the signal amplification circuit 4;
is a threshold setting circuit that variably sets the threshold of the comparator circuit 5. Further, 7 indicates a designated display signal outputted from the scanning signal generation circuit 3, that is, drive lines D1 to D and detection lines S1 to S designated by the scanning pulse outputted from the scanning signal generation circuit 3. By determining the position information and the output signal of the comparator circuit 5, the segment PHI to P9° selected by the selection pen 8 (described later) having a magnetic material at the tip is specified, and a code signal corresponding to the segment is generated. This is a code signal output circuit.

The tablet type input device of this embodiment, which is composed of the above-mentioned parts, performs the following operations.

First, the scanning signal generation circuit 3 outputs a scanning pulse to the detection line control circuit 2 to designate the detection line S1. Next, the scanning signal generation circuit 3 outputs a scanning pulse to the drive line control circuit 1 so that the drive pulse is sequentially applied to all the drive lines DI, D2, . . . D.

Next, the scanning pulse is outputted to the detection line control circuit 2 again, and this time, after specifying the detection line Sz, the scanning pulse is outputted to the drive line control circuit 1, and the drive pulses are sequentially applied to the drive lines D1 to D. so that it is applied. This operation is repeated up to the detection line S.

By the way, while this operation is being performed, the selection pen 8
(described later), for example, if segment P r o is selected, the following phenomenon occurs.

Since the drive line D1 and the detection line S11 are arranged perpendicularly in the segment Pan, the mutual inductance is O(H), and as it is, the drive lines D1 to D
Even if a drive pulse is applied to , no induced current is generated in the detection line SIl, but when a magnetic body is brought close to the drive line DI, the direction of the magnetic field generated by the drive line D1 is disturbed, and as a result, the mutual inductance increases. An induced current is generated in the detection line S.

Therefore, when the selection pen 8 having a magnetic material at the tip approaches the segment Pea, the direction of the magnetic field generated by the drive line D1 is disturbed, and the drive line D
An induced current is generated in the detection line S, which is orthogonal to the signal amplifier circuit 4.
After being input to and amplified, the signal is input to a comparison circuit 5, and if the instantaneous value of the induced current exceeds a threshold value, a detection signal is output to a code signal output circuit 7.

The code signal detection circuit 7 judges this detection signal and the specified display signal outputted from the scanning signal output circuit 3 mentioned above, and outputs a code signal corresponding to the segment P+u.

Next, the specific structure of the selection pen 8 in this embodiment will be explained in the second section.
This will be explained based on Figures (a) and (b).

The selection pen 8 has a cylindrical portion 8 inside a cylindrical portion 8b at the tip of the main body 8a.
It has a cylindrical magnetic body 8C having a smaller diameter than the inner diameter of b. A cylindrical member 8d made of a magnetic shielding material is movably inserted into the gap between the cylindrical portion 8b and the magnetic body 8C.

Furthermore, a coil spring 8e is fixed to the bottom of the cylindrical portion 8b and the tip of the cylindrical member 8d, thereby urging the cylindrical member 8d outward.

Therefore, normally, as shown in FIG. 2(a), the cylindrical member 8d
protrudes from the tip of magnetic body 8C, so magnetic body 8C
Although the selection pen 8 is not exposed, the selection pen 8 is placed on the board surface of the tablet type input device of this embodiment (the drive line and the detection line are arranged perpendicular to each other, and above it is covered with a sheet on which the characters/symbols to be selected are printed). When the main body 8a is pushed down so as to be pressed against the part that is attached to the main body 8a, the coil spring 8e is compressed and the magnetic body 8C comes into contact with the board surface.

Therefore, as described above, each segment PI in which the drive lines D1 to D and the detection lines 81 to S are orthogonal
When the selection pen 8 having the above configuration is pressed on any of + to P and □, the direction of the magnetic field generated by the drive line in this segment is disturbed due to the approach of the magnetic body 8C, and an induced current is generated in the corresponding detection line. This induced current is detected by the process described above, and a code signal corresponding to the designated segment is output.

In this way, in this embodiment, the magnetic material 8C of the selection pen 8
approaches each segment while being surrounded by the cylindrical member 8d made of a magnetic shielding material, the influence of the magnetic field on adjacent segments can be minimized. Even if some leakage flux occurs, if the threshold value is appropriately set by the threshold value setting circuit 6, the influence on adjacent segments can be suppressed to an almost negligible level, and no malfunction will occur.

[Effects of the Invention] As explained above, the tablet type input device of the present invention has the following effects:
A predetermined number of drive lines and detection lines are orthogonally arranged to set segments corresponding to each character/symbol, and while sequentially specifying the detection lines, drive pulses are sequentially applied to the drive lines to attach a magnetic material to the tip. bringing a selection pen having a structure close to the segment to disturb the direction of the magnetic field generated by the drive line at that location to generate an induced current in the detection line;
Since the device is configured to detect this induced current and output a code corresponding to the selected character/symbol, there is no need to interpose a signal line between the tablet and the selection pen.

Moreover, since the selection pen can be configured to be extremely simple and lightweight, operability is dramatically improved.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention, and FIGS. 2(a) and 2(b) are cross-sectional views showing the structure of a selection pen used in the embodiment of the present invention. 1・・・・・・・・・・・・・Drive 9421111
Circuit 2......Detection line control circuit 3...Scanning signal generation circuit 4... ......Signal amplification circuit 5.
......Comparison circuit 6...
......Threshold setting circuit 7...
...... Code signal output circuit 8 ......
...... Selection pens D1-D,... Drive line 5I-8ll... Detection line

Claims (1)

[Claims] (1) Drive lines arranged in a plurality of parallel rows, detection lines arranged in a plurality of rows adjacent to and perpendicular to the drive lines, and a drive line control means for sequentially applying pulse current to the drive lines. a selection pen that has a magnetic material at its tip and selects the orthogonal point between the drive line and the detection line by bringing the magnetic material close to the drive line; 1. A tablet-type input device comprising: a detection line in which an induced current is generated due to approach; and a determination means for determining the orthogonal point selected by the selection pen by detecting a detection line in which an induced current is generated due to approach.