JPH0789311B2 - Coordinate input device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a coordinate input device having good operability and high position detection accuracy.

(Prior Art) As a conventional coordinate input device, a pulse current is applied to one end of a magnetostrictive transmission medium or a drive coil provided at the tip of a position indicator to generate a magnetostrictive vibration wave in the magnetostrictive transmission medium. The time required to detect the induced voltage based on the magnetostrictive vibration wave in the detection coil provided at the tip of the position indicator or at one end of the magnetostrictive transmission medium is measured with a processing device, etc., and the designated position of the position indicator is calculated from this There was something I did. Further, as another conventional coordinate input device, a plurality of drive lines and detection lines are arranged orthogonally to each other, and the induced voltage is detected by sequentially applying current to the drive lines and sequentially selecting the detection lines, There has been a device in which a position designated by a position indicator having a magnetic material such as ferrite is detected from the position of a detection line in which a large induced voltage is induced.

(Problems to be Solved by the Invention) However, although the position detection accuracy is relatively good in the former device, a code is required between the position indicator and the processing device or the like in order to exchange the timing signal and the like, There is a problem that the handling thereof is extremely limited and the position indicator has to be used in close proximity to the magnetostrictive transmission medium. Also, in the latter device, the position indicator can be made cordless, but the resolution of the coordinate position is determined by the line spacing, and if the line spacing is reduced to increase the resolution, the SN ratio and stability deteriorate, so However, it is difficult to increase the resolution, it is difficult to detect the position directly above the intersection of the drive line and the detection line, and there is the problem that the position indicator must be brought very close to the line. It was

The present invention solves the above-mentioned problems of the prior art, and provides a device in which a position indicator is not connected to anywhere, has good operability, has high position detection accuracy, and can easily fix or remove a menu sheet, a drawing, or the like. Aim to achieve.

(Means for Solving the Problems) In order to achieve the above-mentioned object in the present invention, as the first invention,
A plurality of X-direction magnetic bodies arranged substantially parallel to each other,
It has a structure in which a plurality of Y-direction magnetic bodies arranged substantially parallel to each other are superposed so as to be substantially orthogonal to each other, and the plurality of X-direction magnetic bodies are orthogonal to their longitudinal directions. A plurality of X-direction excitation lines and detection lines which are alternately arranged, and a plurality of Y-direction excitation lines and detection which are alternately arranged in the plurality of Y-direction magnetic bodies so as to be orthogonal to their longitudinal directions. A tablet having lines, a drive current source for applying an alternating current of a predetermined cycle to each of the X-direction and Y-direction excitation lines, and an X-direction and a Y-direction connected to each of the X-direction and Y-direction detection lines. Signal selecting circuit, a position specifying magnetic generator for applying a local magnetic bias to the magnetic material, and the position specifying magnetic generator from the induced voltages extracted from the X direction and Y direction signal selecting circuits. In the X direction at the specified position by An electrostatic attraction plate including a position detection device including a position detection circuit for obtaining position data in the Y direction, and an electrostatic adsorption plate having an adsorption layer on one surface, and a high DC voltage applied to the electrostatic adsorption plate. A power supply circuit for supplying the electrostatic attraction plate and a coordinate input device in which the electrostatic attraction plate is mounted on a tablet so that the surface opposite to the attraction layer is in contact with the tablet, and as a second invention, a position detection device similar to the above is provided. And an electrostatic adsorption plate having adsorption layers provided on both sides thereof, and a power supply circuit for supplying a high DC voltage to the electrostatic adsorption plate, the electrostatic adsorption plate being in contact with either one of the adsorption layers. We propose a coordinate input device mounted on a tablet.

(Operation) According to the first aspect of the invention, the magnetic flux changes between the excitation line and the detection line only in the magnetic body, the coupling is dense, the detection voltage is large, and the SN ratio is good. It is less susceptible to external noise, less inductive noise is generated to the outside, and the position-specified magnetic generator does not need to send timing signals for position detection to the device side, so it is cordless with the device. Therefore, the operability is good, and since the position can be specified by applying a slight magnetic bias to the magnetic material, it is not necessary to bring the position specifying magnetic generator close to the tablet, and an interval of several cm or more can be set. The position can be detected with high resolution even when opening or interposing an object other than a magnetic material, and the Coulomb force of static electricity generated in the adsorption layer of the electrostatic adsorption plate fixes and holds menu sheets and drawings on the tablet. It can be, also, can be removed only immediately power down.

Further, according to the second aspect of the invention, in addition to the same operation as described above, the electrostatic attraction plate itself can be attached to and detached from the tablet.

(Embodiment) FIGS. 1 to 10 show a first embodiment of the present invention, in which 10 is an electrostatic attraction plate, 20 is a power supply circuit, 40 is a magnetic generator for position designation, and 70 Is a tablet, and 80 is a position detection circuit.

As shown in FIGS. 2 and 3, the electrostatic attraction plate 10 includes a back surface insulating layer 11, comb-shaped electrodes 12 and 13, terminals 14 and 15, and a surface attraction layer 16. As the back insulating layer 11, a material having an electric resistivity of 10 ¹⁵ Ωcm or more and a dielectric constant of 4 or less, for example, a thickness of 5 m
Use a hard vinyl chloride plate of m.

For the electrodes 12 and 13, for example, polyvinyl chloride, conductive carbon black, and plasticizer (polyester) are kneaded in the same weight to form a conductive plastic sheet having a thickness of 0.5 mm, which is punched out to form a comb shape. None, further arranged on the insulating layer 11 so that the teeth of the comb are alternately engaged with each other at equal intervals, heat-bonded by a heat press and embedded in the upper surface of the insulating layer 11, and the surface is finished to be a smooth surface. It was done.

The terminals 14 and 15 are made of normal copper or the like, and are connected to the electrodes 12 and 13 by the same copper flat braided wire which is also heat-bonded.

The adsorption layer 16 has an electric resistivity of 10 ⁵ to 10 ¹² Ωcm and a dielectric constant of 4 to 12
0.5mm thick sheet of plastic dielectric material such as nitrile butadiene rubber and methylmethacrylate resin (for vinyl chloride modification) taken in equal amount, mixed with 1/10 carbon black and kneaded with a hot roll This sheet is formed into a shape by stacking the sheet on the electrode-embedded surface of the insulating layer 11 and bonding them by hot pressing.

The characteristics of the electrostatic attraction plate 10 are as follows, for example.

Electric resistivity of adsorption sheet 10 ¹¹ Ωcm Dielectric constant of adsorption sheet 8 Insulation resistance value between terminals 1000 MΩ Electrode resistivity of electrode 50 Ωcm Electric resistivity of insulating layer 10 ¹⁶ Ωcm Dielectric constant of insulating layer 3 This electrostatic adsorption plate 10 The suction surface 17 is embedded flush with the periphery of the tablet 70 through an insulating sheet (not shown) in the approximate center of the case, and the terminals 14 and 15 are connected to the power supply circuit 2
Connected to 0.

Then, a non-adsorbed material A such as a menu sheet or a drawing is placed on the adsorbing surface 17, and the terminals 14 and 15 are connected to the power supply circuit 20 and the direct current is 1,000 to 5 times.
When a voltage of 1,000 volts is applied, as shown in FIG. 2, electric charges having different signs from those on the electrodes are excited by the dielectric polarization phenomenon, and an electrostatic force is generated between the non-adsorbed substance A, which is attracted and held. Further, when the power supply circuit 20 is disconnected, the electric charge is generated in the adsorption layer 16
The non-adsorbed substance A can be exfoliated very easily.

The power supply circuit 20 includes a well-known rectifier, transformer, DC-DC converter, and the like, and supplies necessary power to the position detection circuit 80 in addition to the DC voltage of 1,000 to 5,000 volts.

FIG. 4 is a cross-sectional view showing the structure of a position specifying magnetic generator (hereinafter referred to as an input pen) 40, and FIG. 5 is an electric circuit diagram thereof. In the figure, 41 is a pen-shaped container made of synthetic resin or the like, and a bar magnet 42 having a tapered tip is accommodated at one end of the pen-shaped container so as to be slidable in the axial direction. Further, an infrared transmitting window 43 made of transparent plastic or the like is provided in the other end side of the container 41 in the circumferential direction, and a reflector 44 having a peripheral surface of a cone body plated with chrome or the like is provided inside thereof. An infrared light emitting diode 45 and is housed. 46a and 46b are operation switches. The operation switch 46a is attached to one side of the front end side of the container 41, and the operation switch 46b is attached to the other end of the bar magnet 42 so as to face it. Further, 47 is a signal generating circuit, and 48 is a battery, which is housed in an appropriate place in the container 41. Signal generation circuit 47
Is to convert a plurality of (here, three) commands to the position detection circuit 80 such as measurement start and position input into a plurality of code signals by combining several pulse signals. The decoder 47a and the code signal generator. 47b and a diode driving transistor 47c are provided, a code signal is generated according to a combination of ON / OFF of the operation switches 46a and 46b, and the light emitting diode 45 is driven. Then, when the operation switch 46a is turned on, an infrared signal indicating a measurement start code is transmitted from the diode 45 through the reflector 44 and the transmission window 43, and the tip of the bar magnet 42 with the cover 49 attached is directly input to the input surface. When pressed against, the bar magnet 42 slides to turn on the switch 46b, and an infrared signal indicating a code signal for position input is transmitted.

FIG. 6 is an exploded perspective view of the tablet 70. Tablet
70 is a shield plate 710a, magnetic plates 720a, 720b, conductor plates 730a, 730b, magnetic plates 720c, 720d,
Conductor plates 730c, 730d, magnetic plates 720e, 720f, shield plate 710b
It consists of 12 layers.

As the shield plates 710a and 710b, a printed board in which a copper plate 712 is attached to one surface of an insulating board 711 such as glass epoxy is used.

The magnetic material plates 720a to 720f are composed of a plurality of (eight in the illustrated example) long magnetic materials 721 arranged substantially parallel to each other, and sandwiched between two insulating substrates such as glass epoxy and thermocompression bonded. Etc. are integrated. Here, as the magnetic body 721, a material that is hard to be magnetized even if a magnet is brought close to it, that is, has a small holding force and a high magnetic permeability (μ), for example, a diameter of about 0.1 m.
An amorphous wire with a circular cross section of m is used. As the amorphous wire, for example, (Fe _1-x Co _x ) ₇₅ Si ₁₀ B
₁₅ (atomic%) (x represents the ratio of Fe and Co, and is 0 to
Takes a value of 1. ) Etc. are suitable.

Conductor plates 730a to 730d are formed by etching a printed circuit board in which a copper plate is attached to one surface of an insulating substrate such as glass epoxy to form a conductor having land holes at a plurality of (17 in the illustrated example) both ends. It will be.

Between the magnetic plates 720a and 720b, between 720c and 720d, and 720e and 720
The f parts are bonded and fixed by thermocompression bonding, and the other substrates are bonded and fixed via a bonding sheet. At this time, the magnetic plates 720a, 7
The magnetic bodies of 20c and 720e are arranged in the Y direction, the magnetic bodies of the magnetic body plates 720b, 720d and 720f are arranged in the X direction, and the conductors of the conductor plates 730a and 730c are orthogonal to the Y direction and the conductor plates 730b and 730d. Conductors are arranged in a direction orthogonal to the X direction.

As another manufacturing method, two magnetic plates are thermocompression-bonded so that the magnetic plates are orthogonal to each other, the printed boards are bonded and fixed to both outer sides thereof, and then a conductor is formed by etching treatment, Or, without forming, the shield plate
710a, magnetic plates 720a, 720b, conductor plate 730a set, conductor plate 730b,
A set of magnetic plates 720c and 720d, a conductor plate 730c, and a conductor plate 730
A set of d, the magnetic plates 720e and 720f, and the shield plate 710b may be created, and these may be further bonded and fixed. The total thickness of the tablet 70 is actually about 3 to 5 mm,
In the drawing, only the thickness direction is shown enlarged. Also,
In tablet 70, magnetic plates 720a, 720b, 720e, 720f
In order to obtain a larger electromagnetic induction by forming a path of magnetic flux generated around the excitation line by the magnetic material 721 therein, it is not necessary to provide it. Further, the shield plates 710a and 710b are for preventing normal noise from being mixed in from the outside and inducing noise to be emitted to the outside.

The conductors of the conductor plates 730b and 730d are such that vertically overlapping conductors are connected to each other by a through hole process at a land hole at one end, and an exciting wire 740a in the X direction that winds around the magnetic body 721 in the magnetic body plate 720d. ~ 740i and detection lines 750a-750h are formed alternately. The other ends of the excitation lines 740a to 740i on the conductor plate 730b side are connected to the other ends of the adjacent excitation lines 740a to 740i on the conductor plate 730d side, that is, connected in series, and the other end of the excitation line 740a and the excitation line 74 are connected.
The other end of 0i is connected to the drive current source in the position detection circuit 80. The other ends of the detection lines 750a to 750h on the side of the conductor plate 730b are connected to the multiplexer 780, respectively.
The other ends of a to 750h on the side of the conductor plate 730d are commonly grounded.

The respective conductors of the conductor plates 730a and 730c are such that conductors that are vertically overlapped with each other are connected by a through hole process at a land hole at one end, and an exciting wire 760a in the Y direction that winds around the magnetic body 721 in the magnetic body plate 720c. ~ 760i and detection lines 770a to 770h are formed alternately. The other ends of the excitation lines 760a to 760i on the side of the conductor plate 730a are connected to the other ends of the adjacent excitation lines 760a to 760i on the side of the conductor plate 730c, that is, connected in series, and the other end of the excitation line 760a and the excitation line 76.
The other end of 0i is connected to the drive current source. In addition, each detection line 77
The other ends of 0a to 770h on the conductor plate 730a side are respectively connected to the multiplexer 790, and the other ends of the detection lines 770a to 770h on the conductor plate 730c side are commonly grounded.

FIG. 7 is a circuit block diagram showing a specific configuration of the position detection circuit 80. The operation of each circuit block will be described in detail below.

When the power of the position detection circuit 80 is turned on, a sinusoidal alternating current is supplied from the drive current source 81 to the excitation lines 740a to 740i and 760a to 760i of the tablet 70. At this time, the excitation lines 740a to 740i and 760a to 760i are connected to the detection lines 750a to 750h and 770a to 770h.
An induction voltage is generated by electromagnetic induction based on the alternating current flowing through the. This electromagnetic induction is applied to the magnetic material 721 of the magnetic material plates 720a to 720f.
Therefore, the larger the magnetic permeability of the magnetic material 721, the larger the voltage value of the induced voltage. By the way, the magnetic permeability of the magnetic body 721 greatly changes due to a magnetic bias applied from the outside. The change is different depending on the composition of the magnetic material, the frequency of the alternating current, or the heat treatment of the magnetic material, and it becomes maximum when a predetermined amount of magnetic bias is applied as shown in FIG. Can be set. Therefore, in this case, when the predetermined amount of magnetic bias is applied to the magnetic body 721, the excitation lines 740a to 740i, 7
The voltage induced from 60a to 760i to the detection lines 750a to 750h and 770a to 770h becomes large.

Now, insert the tip of the bar magnet 42 of the input pen 40 from the detection line 750a to X
It is assumed that the predetermined amount of magnetic bias is applied to the magnetic material 721 by pressing it against the position of the input surface that is separated by the distance x _{s in the} direction and the distance y _{s in the} Y direction from the detection line 770a.

At this time, induced voltages V _{1 to} V ₈ as shown in FIG. 9 are generated on the detection lines 750a to 750h in the X direction. The In FIG. 9, the horizontal axis represents the coordinate position in the X direction to x ₁ ~x ₈ the position of the detection line 750a~750h respectively, although the vertical axis indicates the voltage value, the respective voltage V ₁ ~V ₈ is the maximum value (maximum value) immediately below the input pen 40.

On the other hand, at this time, when the switch 46a of the input pen 40 is turned on, the light emitting diode 45 transmits an infrared signal indicating a measurement start code. The infrared signal is received by the infrared light receiving diode 82, further amplified and shaped by the receiver 83, converted into the original code signal, further converted into the command signal for starting the measurement, and sent to the input buffer 84. When the arithmetic processing circuit 85 reads the command signal from the input buffer 84 and recognizes the start of measurement, it sends a control signal to the multiplexer 780 via the output buffer 86 and the detection lines 750a to 750h in the X direction.
The induced voltage is sequentially input to the amplifier 87. Each of the induced voltages is amplified by an amplifier 87, rectified by a detector 88 and converted into a DC voltage, and further an analog / digital (A / D) converter 89.
Is converted into a digital value at and is sent to the arithmetic processing circuit 85 via the input buffer 84. The arithmetic processing circuit 85 temporarily stores the induced voltages (digital values) in the memory 810, and obtains the coordinate value x _s in the X direction from them.

There are various possible methods of calculating the coordinate value x _s , but the induced voltage is approximated to the induced voltage near the maximum value by focusing on the point that the voltage directly under the input pen 40 is the maximum value and decreases on both sides thereof. Find the function and use the coordinate values as the coordinates of the maximum of that function.
There is a way to find x _s .

Here, for example, the intervals between the detection line 750a~750h and [Delta] x, (in the figure, indicated by a solid line) the secondary function of the coordinates x ₃ to the coordinates x ₅ in Figure 9 is approximated by, in the following manner It can be calculated. First, V ₃ = a (x ₃ -x _s ) ² + b …… (1) V ₄ = a (x ₄ -x _s ) ² + b …… (2) V from the voltage and coordinate value of each detection line ₅ = a (x ₅ -x _s ) ² + b (3) Here, a and b are constants (a <0). Further, x ₄ -x ₃ = Δx (4) x ₅ -x ₃ = 2Δx (5) Substituting equations (4) and (5) into equations (2) and (3) and rearranging, x _s = x ₃ + Δx / 2 {(3V ₃ -4V ₄ + V ₅ ) / (V ₃ -2V ₄ + V ₅ )} ……
(6) Therefore, the detection lines 750c, 750d, 750e are added to the equation (6).
The X-coordinate value x _s can be obtained by substituting the voltages V ₃ , V ₄ , V ₅ induced in the and the coordinate value x ₃ (known) of the detection line 750c for calculation.

Arithmetic processing circuit 85, first the maximum value from among the induced voltage (here, the maximum voltage value) to detect the induced voltage V _k with. Further, the arithmetic processing circuit 85 extracts the induction voltage V _k and the induction voltages V _k−1 and V _{k + 1} before and after the induction voltage V _k from the memory 810, and outputs these as the voltages V ₃ , V ₄ and V ₄ in the equation (6), respectively. The calculation processing of equation (6) is performed as V ₅ , and the X coordinate value x _s is obtained.

Next, the arithmetic processing circuit 85 sends a control signal to the multiplexer 790 via the output buffer 86, and the detection lines 770a to 770 in the Y direction.
Input the induced voltage of h sequentially and perform the same process as above.
Calculate the coordinate value y _s .

The X and Y coordinate values of the digital value obtained in this way are temporarily stored in the memory 810. While the signal indicating the start of measurement is output, the measurement and calculation as described above takes a predetermined time. It is repeated every time and the value is updated. Next, when the tip of the input pen 40 is strongly pressed against the input surface and the switch 46b is turned on, an infrared signal indicating a position input code is transmitted from the light emitting diode 45 and the light receiving diode 8
2, arithmetic processing circuit 85 via receiver 83 and input buffer 84
, The digital value X at that time is recognized.
And the Y coordinate value are sent as input values to a computer or the like. Thereafter, this process is repeated, and the position data to be designated one after another can be obtained.

FIG. 10 shows a specific example of the drive current source 81. In the figure, reference numeral 81a denotes an integrating circuit, which receives a clock pulse of the arithmetic processing circuit 85 (or a pulse obtained by dividing the clock pulse) as an input signal, integrates it, and converts it into a triangular wave signal. 81b is a band pass filter, which converts the triangular wave signal into a sine wave signal. Reference numeral 81c is a power driver, which is composed of an operational amplifier and a current amplifier, and current-amplifies the sine wave signal and sends it to the excitation lines 740a to 740i and 760a to 760i. The clock pulse is used as the reference (input) signal in order to synchronize with the position detection circuit 80.

In addition, it goes without saying that the numbers of magnetic bodies, excitation lines, and detection lines in the examples are merely examples, and are not limited thereto.
Further, it has been confirmed by experiments that the position can be detected relatively accurately if the distance between the detection lines is about 2 to 6 mm. Further, the position specifying magnetic generator is not limited to the bar magnet, and may be a plate, a ring, a rectangular body or the like, or an electromagnet.

FIG. 11 shows a second embodiment of the present invention. In the figure, reference numeral 60 designates an attraction plate, which is formed by joining the electrostatic attraction members 61 and 62 having the same configuration as the above-mentioned electrostatic attraction plate 10 by bonding the insulating layers to each other with an adhesive or the like. . Then, when the attraction plate 60 is placed in the approximate center of the upper surface of the case of the tablet 70 and a high DC voltage is applied to the electrodes of both electrostatic attraction bodies 61 and 62 from the power supply circuit 20, the electrostatic attraction body The attraction plate 62 fixes the attraction plate 60 to the tablet 70, while the non-adsorption substance is fixed by the attraction force of the electrostatic attraction body 61. Therefore, according to this embodiment, the suction plate 60 can be attached to and detached from the tablet 70. Other configurations
The operation is similar to that of the first embodiment.

The suction plate 60 may be integrally configured by providing a plurality of electrodes and suction layers on both surfaces of one insulator.

(Effect of the Invention) As described above, according to the first invention, a plurality of X-direction magnetic bodies arranged substantially parallel to each other and a plurality of Y-direction magnetic bodies arranged substantially parallel to each other are provided. A plurality of X-direction excitation lines and a plurality of detection lines which are superposed so as to be substantially orthogonal to each other and which are alternately arranged in parallel in the plurality of X-direction magnetic bodies so as to be orthogonal to their longitudinal directions. A tablet having a plurality of Y-direction exciting lines and a plurality of Y-direction exciting lines alternately arranged on the plurality of Y-direction magnetic bodies so as to be orthogonal to their longitudinal directions; and each of the X-direction and Y-direction exciting lines. A drive current source for applying an alternating current of a predetermined cycle to
X-direction and Y-direction signal selection circuits respectively connected to the respective detection lines in the Y-direction and the Y-direction, a position-designating magnetic generator for applying a local magnetic bias to the magnetic body, and the X-direction and Y-direction Since the position detecting device is provided with a position detecting circuit for obtaining position data in the X direction and the Y direction of the specified position by the position specifying magnetic generator from each induced voltage taken out from the signal selecting circuit, the excitation line is provided. The magnetic flux between the detection line and the detection line is changed only in the magnetic body, the coupling is dense, the detection voltage is large, the SN ratio is good, and it is difficult to receive induction from the outside and the induction noise to the outside is generated. In addition, the magnetic generator for position specification does not need to send timing signals for position detection to the device side, it can be cordless between the device and the cord, and the cord may be disconnected due to fatigue. It does not get tangled or mess up, so it has good operability, the position specifying magnetic generator can be easily moved to any position, and only a slight magnetic bias is applied to the magnetic material. Since it is possible to specify the position with, it is not necessary to bring the position specifying magnetic generator close to the tablet, it may be spaced by several cm or more, and an object other than a magnetic substance may be interposed. But position can be detected with high resolution. Further, an electrostatic adsorption plate having an adsorption layer provided on one surface and a power supply circuit for supplying a direct current high voltage to the electrostatic adsorption plate are provided, and the electrostatic adsorption plate is in contact with the surface opposite to the adsorption layer. Since it is mounted on the tablet with the electrostatic attraction plate, the menu sheet, drawings, etc. can be fixed and held on the tablet by the Coulomb force of static electricity generated on the electrostatic attraction plate, and it can be immediately removed by simply turning off the power supply. In addition, these sheets can be easily attached and detached, and there is no risk of damage as in the case of using an adhesive tape.

According to the second aspect of the invention, the electrostatic attraction plate is provided with the attraction layers on both sides thereof, and the power supply circuit for supplying a high DC voltage to the electrostatic attraction plate. Since either one of them is placed on the tablet in contact with it, there is an advantage that the electrostatic attraction plate itself can be attached / detached to / from the tablet.

[Brief description of drawings]

FIG. 1 is a perspective view showing the outline of a first embodiment of a coordinate input device of the present invention, FIG. 2 is a longitudinal sectional view of an electrostatic attraction plate, and FIG. 3 is a view taken along the line III-III in FIG. 4 is a sectional view showing the structure of the input pen, FIG. 5 is an electric circuit diagram thereof, FIG. 6 is an exploded perspective view showing a concrete structure of the tablet, and FIG. 7 is a position detecting circuit. Block diagram, FIG. 8 is a characteristic diagram of magnetic bias vs. magnetic permeability, FIG. 9 is a graph showing an example of an induced voltage generated in each detection line in the X direction, and FIG. 10 is an electric diagram showing a concrete example of a drive current source. A circuit diagram, FIG. 11 is a schematic perspective view showing a second embodiment of the present invention. 10,60 ... Electrostatic attraction plate, 11 ... Insulating layer, 12,13 ... Electrode,
14,15 terminals, 16 adsorption layer, 20 power circuit, 40
… Positioning magnetic generator, 70 …… Tablet, 80 …… Position detection circuit.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshinori Taguchi 1342-3 Tohokudori, Sugaya, Ageo City, Saitama Prefecture Wacom Co., Ltd. (56) References JP 58-2985 (JP, A) JP 57 -58872 (JP, B1)

Claims (2)

[Claims] 1. A structure in which a plurality of X-direction magnetic bodies arranged substantially parallel to each other and a plurality of Y-direction magnetic bodies arranged substantially parallel to each other are superposed so as to be substantially orthogonal to each other. And a plurality of X-direction excitation lines and detection lines, which are alternately arranged on the plurality of X-direction magnetic bodies so as to be orthogonal to their longitudinal directions, and the plurality of Y-direction magnetic bodies. A tablet having a plurality of Y-direction excitation lines and detection lines which are alternately arranged so as to be orthogonal to the longitudinal direction, and a drive current for applying an alternating current of a predetermined cycle to each of the X-direction and Y-direction excitation lines. A source, an X-direction and Y-direction signal selection circuit connected to each of the X-direction and Y-direction detection lines, a position-specified magnetic generator that applies a local magnetic bias to the magnetic body, Direction and Y direction signal selection circuit A position detecting device comprising a position detecting circuit for obtaining position data in the X direction and the Y direction of a specified position by the position specifying magnetic generator from each induced voltage outputted, and an adsorption layer on one surface. And a power supply circuit for supplying a high DC voltage to the electrostatic attraction plate, and the electrostatic attraction plate is mounted on the tablet with the surface opposite to the attraction layer in contact with the electrostatic attraction plate. Characteristic coordinate input device. 2. A structure in which a plurality of X-direction magnetic bodies arranged substantially parallel to each other and a plurality of Y-direction magnetic bodies arranged substantially parallel to each other are superposed so as to be substantially orthogonal to each other. And a plurality of X-direction excitation lines and detection lines, which are alternately arranged on the plurality of X-direction magnetic bodies so as to be orthogonal to their longitudinal directions, and the plurality of Y-direction magnetic bodies. A tablet having a plurality of Y-direction excitation lines and detection lines alternately arranged in parallel so as to be orthogonal to the longitudinal direction; and a drive current source for applying an alternating current of a predetermined cycle to each of the X-direction and Y-direction excitation lines. An X-direction and Y-direction signal selection circuit connected to each of the X-direction and Y-direction detection lines; a position specifying magnetic generator that applies a local magnetic bias to the magnetic body; Extracted from the Y direction signal selection circuit A position detecting circuit for obtaining position data in the X direction and the Y direction of a specified position by the position specifying magnetic generator from each induced voltage, and an adsorption layer is provided on both surfaces. And an electric power supply circuit for supplying a high DC voltage to the electrostatic adsorption plate, and the electrostatic adsorption plate is placed on a tablet in contact with either one of the adsorption layers. And coordinate input device.