JPH0630042B2 - Position detector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention is an improvement of a position detecting device capable of detecting coordinate values of a position on a tablet specified by a position specifying magnetic generator that generates a stationary magnetic field. It is about.

(Prior Art) In this type of conventional position detecting device, the power switch is turned on, the control circuit starts the position detecting operation, and the position specifying magnetic generator enters the position detecting range of the tablet (accurately). Speaking of, when the strength of the magnetic field applied to the tablet from the position specifying magnetic generator exceeds a certain level at which the position can be detected, the position specifying magnetic generator moves (moves or stops). Position detection is performed in a predetermined cycle (for example, about 200 times per second) regardless of whether or not the coordinate values are obtained.

A large number of coordinate values thus obtained in time series are
It contains many coordinate values and the same coordinate values corresponding to each position of the position specifying magnetic generator that is moving from one input position to another input position, and all of them should be input. It does not correspond to the position.

Therefore, conventionally, a switch is provided on the position specifying magnetic generator, and a timing signal indicating that the switch is turned on (or off) is sent to the tablet side via a code or using ultrasonic waves or infrared rays. The control signal is sent to the connected control circuit, and the coordinate signal corresponding to the position to be input is specified from the plurality of coordinate values by the timing signal, that is, the position to be input is specified.

(Problems to be Solved by the Invention) However, in the case of transmitting a timing signal via a code, the code deteriorates the operability of the position specifying magnetic generator, and the timing signal is transmitted using ultrasonic waves or infrared rays. In this case, the position specifying magnetic generator must be provided with these transmitters, signal generating circuits, batteries, etc., which makes the structure complicated and expensive, and also makes it large and heavy, and in this case also operability at the time of input There was a problem that was worse.

(Means for Solving the Problem) In the present invention, in order to solve the above-mentioned problems, the position on the tablet to which a stationary magnetic field is applied from a substantially rod-shaped position-designating magnetic generator that can be moved to an arbitrary position is used. In a position detecting device that repeatedly detects coordinate values while the magnetic field strength is above a certain level, a portion on the tablet where the hand having the substantially rod-shaped position specifying magnetic generator contacts the tablet, and A touch panel having a switch matrix structure consisting of a number of substantially square switches whose one side length is smaller than the average distance between one end of a substantially rod-shaped position specifying magnetic generator and the part in contact with the tablet is stacked. While matching, select a switch including the detected position in the touch panel, and detect the timing when the substantially bar-shaped position specifying magnetic generator contacts the switch. Then, the timing signal generating means for generating the timing signal for specifying the coordinate value corresponding to the position to be input among the obtained coordinate values is provided.

In addition, the coordinate value of the position on the tablet to which a steady magnetic field is applied from a substantially rod-shaped position specifying magnetic generator that can be moved to any position is repeatedly detected while the magnetic field strength is above a certain level. In the position detecting device, a flat display panel is overlaid on the tablet, and the portion having the substantially rod-shaped position specifying magnetic generator on the tablet and the portion for contacting the tablet with the substantially rod-shaped position specifying device. A translucent touch panel having a switch matrix structure composed of a large number of substantially square switches whose one side length is smaller than the average distance between the one end of the magnetic generator and the tablet contacting portion is stacked. , Selecting a switch including the detected position in the touch panel, and detecting the timing when the substantially bar-shaped position specifying magnetic generator contacts the switch. , Provided a timing signal generating means for generating a timing signal for specifying the coordinate values corresponding to be the input position of the resulting coordinate values.

(Operation) According to the present invention, the timing signal for specifying the coordinate value corresponding to the position to be input among the obtained coordinate values only by pressing the substantially bar-shaped position specifying magnetic generator on the touch panel. Therefore, it is not necessary to install a transmitter for sending timing signals, a signal generation circuit, a battery, etc. to the magnetic field generator for specifying the position, and it is as natural as an ordinary writing instrument. In addition to being operable, the timing signal can be extracted from only the switch that includes the detected position in the switch matrix that makes up the touch panel, and the timing signal is output even when a hand other than the position specifying magnetic generator touches the touch panel. Therefore, there is no risk of inputting incorrect coordinate values.
Further, according to the display panel provided, it is possible to operate while displaying the input character or figure.

(Embodiment) FIG. 1 shows a basic configuration of the present invention.
Is an input / output panel, 2 is a control device, 3 is a position specifying magnetic generator, and 4 is a power supply device.

In the input / output panel 1, as shown in FIGS. 1 and 2, a backlight 30 and a flat display panel, for example, a liquid crystal display panel 40 are mounted on a tablet 10 via a shield plate 20. It is integrally housed in a case 50 made of non-magnetic metal or the like.
A translucent touch panel 60 is rotatably attached to the upper surface of the case 50 at its rear end.

As shown in FIG. 3, the control device 2 controls a tablet control circuit 5 for controlling the tablet 10, a touch panel control circuit 6 for controlling the touch panel 60, a liquid crystal display panel control circuit 7 for controlling the liquid crystal display panel 40, and controls these. It is composed of an electronic computer 8 which is controlled dynamically.

Magnetic generator for position specification (hereinafter referred to as input pen) 3
Is a pen shaft 301 made of synthetic resin or the like as shown in FIG.
A bar magnet 303 having a tapered tip is housed in one end 302 of the.
A protective cover 304 made of plastic or the like is attached to the tip of the bar magnet 303.

The power supply device 4 includes a well-known rectifier, transformer, DC-DC converter, and the like, and supplies necessary power to the backlight 30 and each circuit in the control device 2.

FIG. 5 is a plan view showing the structure of the tablet 10, and FIG. 6 is a sectional view taken along the line VI-VI in FIG. In the figure, 11 is a magnetostrictive transmission medium, and a plurality of magnetostrictive transmission media are provided in the X direction and the Y direction,
They are arranged substantially parallel to each other. The magnetostriction transmission medium 11 can be used as long as it is a ferromagnetic material, but a material having a large magnetostriction effect, for example, an amorphous alloy containing a large amount of iron is particularly desirable in order to generate a strong magnetostriction vibration wave. Further, it is preferable to use a material having a small holding force that is hard to be magnetized even when the magnet is brought close to it. As the amorphous alloy, for example, Fe ₆₇ Co ₁₈ B ₁₄ Si
₁ (atomic%), Fe ₈₁ B _13.5 Si _3.5 C ₂ (atomic%), etc. can be used. The magnetostrictive transmission medium 11 has an elongated shape, and its cross section is preferably a rectangular thin strip or a circular linear shape. In the case of a thin strip, the width is about several mm and the thickness is several μm to several 1
When the thickness is about 0 μm, the production is easy and the characteristics are good. Since an amorphous alloy having a thickness of 20 to 50 μm can be manufactured, it may be cut into a thin plate or a linear shape. In this embodiment, a magnetostrictive transmission medium made of Fe ₈₁ B _13.5 Si _3.5 C ₂ (atomic%) having a width of 2 mm and a thickness of 0.02 mm is used.

Reference numeral 12 is an elongated cylindrical reinforcing member made of an alloy resin or the like, and accommodates the magnetostrictive transmission media 11 therein.

Reference numeral 13 is an X-direction first coil arranged on the reinforcing material 12 at one end of the magnetostrictive transmission medium 11 arranged in the X-direction. The X-direction first coil 13 is twisted between the adjacent reinforcing members 12 and is wound in the opposite direction for each of the magnetostrictive transfer media 11 adjacent to each other. When a current is passed through the coil 13, each magnetostrictive transfer medium 11 is twisted. The magnetic flux generated from the portion corresponding to the above, or the voltage generated in each portion when the magnetic flux in one direction is applied to the coil 13 has the opposite direction. For this reason,
Pulse noise generated when a pulse current is passed through the coil 13 and external induction cancel each other out between adjacent parts of the coil 13 and are weakened. Although the number of windings is one in the illustrated example, it may be two or more. This X
The first directional coil 13 is for generating a momentary magnetic field fluctuation to generate a magnetostrictive oscillating wave in each winding portion of the magnetostrictive transmission medium 11, and one end of the coil 13 is connected to the tablet control circuit 5. The other end is grounded.

Reference numeral 14 denotes a Y-direction first coil arranged on the reinforcing material 12 at one end of the magnetostrictive transmission medium 11 arranged in the Y direction, which is twisted between the adjacent reinforcing materials 12 and is adjacent to each other. Each 11 is wound in the opposite direction. This Y
Similar to the coil 13, one end of the first directional coil 14 is connected to the tablet control circuit 5, and the other end is grounded. The operation is similar to that of the coil 13.

Reference numeral 15 is a reference position specifying magnetic generator, for example, an angular magnet, for applying a bias magnetic field parallel to the longitudinal direction to the winding portion of the X-direction first coil 13 and the winding portion of the Y-direction first coil 14, respectively. It is a thing. The reason for applying the bias magnetic field in this way is to enable generation of a large magnetostrictive vibration wave with a small current and to specify the generation position of this magnetostrictive vibration wave. That is, the electromechanical coupling coefficient of the magnetostrictive transmission medium 11 (from mechanical energy to electrical energy,
Alternatively, the coefficient indicating the conversion efficiency from electrical energy to mechanical energy) becomes maximum at a certain bias magnetic field, as shown in FIG. 7, so that such magnetic bias is applied to the X-direction first coil 13, Y. By applying the directional first coil 14 to the wound portion, the magnetostrictive vibration wave can be efficiently generated.

Reference numeral 16 denotes an X-direction second coil arranged on the reinforcing material 12 over a wide range of the magnetostrictive transmission medium 11 arranged in the X direction. The coils 16 are all wound in the same direction (counterclockwise in this embodiment) on each magnetostrictive transmission medium 11, and are connected in series so that adjacent coils have opposite polarities. Therefore, the direction of the voltage and the current generated in each coil 16 when the magnetic flux in one direction is applied to all the coils 16 or the direction of the magnetic flux generated in each coil 16 when the current flows through the entire coil 16 is adjacent. The coils have opposite directions, and external induction and noise are canceled by adjacent coils and weakened.

The winding pitch of the coil 16 is gradually wound from one end on the side close to the first coil 13 in the X direction toward the other end on the opposite side, and the induced voltage decreases due to the attenuation of the magnetostrictive vibration wave. Is compensating for. Generally, a larger winding pitch is preferable to increase the induced electromotive force. The X-direction second coil 16 is for detecting an induced voltage due to a magnetostrictive vibration wave propagating in the magnetostrictive transmission medium 11, and has one end connected to the tablet control circuit 5 and the other end grounded and wound. The area that is opened is the position detection area.

Reference numeral 17 denotes a second Y-direction element provided on the reinforcing material 12 over a wide range of the magnetostrictive transmission medium 11 arranged in the Y-direction.
The coils 17 are all wound in the same direction (left-handed in this embodiment) on each magnetostrictive transmission medium 11, and are connected in series so that adjacent coils have opposite connection polarities. . Further, the winding pitch of the coil 17 is gradually and densely wound from one end on the side close to the Y-direction first coil 14 to the other end on the opposite side, and one end thereof is the same as the coil 16. Is connected to the tablet control circuit 5, and the other end is grounded. The operation is similar to that of the coil 16.

The X including the magnetostrictive transmission medium 11 in the X direction, the reinforcing material 12, the X direction first coil 13, and the X direction second coil 16 described above.
Direction position detector, Y-direction magnetostrictive transmission medium 11, reinforcing member 12, Y-direction first coil 14, and Y-direction second coil 17
And a position detection section in the Y direction composed of and are stacked so as to be orthogonal to each other, housed in the bottom of the case 50, and fixed with an adhesive or the like. Further, although the reference position specifying angle magnet 15 is fixed to the bottom of the case 50 so as to face the end of the magnetostrictive transmission medium 11, it may be arranged above, below, or side by side of the magnetostrictive transmission medium 11 in parallel. good.

FIG. 8 is a circuit block diagram showing a schematic configuration of the tablet control circuit 5. Hereinafter, the position detection operation by the tablet 10 will be described in detail together with the description of each circuit block.

Now, in the input / output panel 1, the input pen 3 passes through the touch panel 60 to the shield plate 20,
_On the magnetostrictive transmission medium 11 at a distance l _{1 in} the X-axis direction from the coil surface center of the first directional coil 13 and also on the Y-direction first coil 1
It is assumed that magnetism is present on the magnetostriction transmission medium 11 at a distance l _{2 in} the Y-axis direction from the center of the coil plane of No. 4 and has a large electromechanical coupling coefficient.

When the electronic calculator 8 sends a measurement start command signal to the microprocessor 501 of the tablet control circuit 5, the microprocessor 501 sends a switching signal for selecting X of the X and Y switching signals to the multiplexers 502 and 503. The X-direction pulse current generator 504 and the X-direction second coil 16 are selected, and the trigger pulse is applied to the X-direction pulse current generator 504 via the multiplexer 502 to apply the pulse current to the X-direction first coil 13. The trigger pulse is also applied to a counter 506 via a monostable multivibrator (monomulti) 505, the counter 506 is reset and starts counting clock pulses supplied from a clock generator 507. The pulse repetition frequency of the clock pulse of the clock generator 507 is
For example, it is 100 MHz.

The X direction pulse current generator 504 operates and the pulse current becomes X.
When applied to the first directional coil 13, a momentary magnetic field change occurs in the first X-directional coil 13, which causes a magnetostrictive vibration wave to occur in the winding portion of the first X-directional directional coil 13 of the magnetostrictive transmission medium 11. To do. The magnetostrictive vibration wave propagates along the longitudinal direction in the magnetostriction transmission medium 11 at a propagation velocity (5000 m / sec) unique to the magnetostriction transmission medium 11. During this propagation, the mechanical energy is converted to the magnetic energy at the site of the magnetostrictive transmission medium 11 where the magnetostrictive vibration wave exists, depending on the magnitude of the electromechanical coupling coefficient at that site, and therefore the X direction. An induced electromotive force is generated in the second coil 16.

FIG. 9 shows an example of the temporal change of the induced electromotive force generated in the X-direction second coil 16 when the time when the pulse current is applied to the X-direction first coil 13 is t = 0.
As shown in the figure, the amplitude of the induced electromotive force increases from the time t = 0 immediately after the time t ₀ around a lapse t ₁ ~t ₂ seconds, small at other times. The reason why the amplitude of the induced electromotive force increases immediately after the time t = 0 is due to the electromagnetic induction action between the X-direction first coil 13 and the X-direction second coil 16, and is _{1 at} the time t = t _{1 to} t ₂ . The amplitude of the induced electromotive force (induced voltage due to the magnetostrictive vibration wave) of the cycle becomes large because the magnetostrictive vibration wave generated in the winding portion of the X-direction first coil 13 propagates through the magnetostrictive transmission medium 11 and the input pen 3 The reason for this is that the electromechanical coupling coefficient increased near the point immediately below, and the electromechanical coupling coefficient increased at that point. When the input pen 3 is moved along the longitudinal direction of the magnetostrictive transmission medium, the induced voltage due to the magnetostrictive vibration wave also moves on the time axis accordingly. Therefore, from time t ₀ to t
By measuring the time from _{1 to} t _2, it is possible to calculate the position in the X direction designated by the input pen 3, that is, the distance l ₁ . As the propagation time for calculating the position, for example, as shown in FIG. 9, a time point t ₃ when the amplitude of the induced voltage due to the magnetostrictive vibration becomes smaller than the threshold value −E ₁ , and a threshold value E ₁
The time point t ₄ that becomes larger may be used, or the zero-cross point t ₅ may be used.

The induced electromotive force generated in the X-direction second coil 16 described above is sent to the amplifier 508 via the multiplexer 503, amplified, and further sent to the comparator (comparator) 509.
The comparator 509 compares the induced electromotive force with a reference voltage, for example, the threshold value E ₁ described above, and the induced electromotive force is compared with the threshold value E _1.
When it becomes larger than ₁ , that is, when the positive polarity portion of the induced voltage due to the magnetostrictive vibration wave is detected, a stop pulse is sent to the counter 506 and the counting of the counter 506 is stopped.

At this time, the counter 506 obtains a digital value corresponding to the time from the time when the pulse current is applied to the X-direction first coil 13 to the time when the induced voltage due to the magnetostrictive vibration wave appears in the X-direction second coil 16. Further, this value corresponds to the distance l ₁ in the X direction from the X direction first coil 13 to the input pen 3 as the magnetostrictive vibration wave advances at a speed of about 5000 m / s. The microprocessor 501 reads the count value of the counter 506 at this time, that is, the X-direction position data.

Then, the microprocessor 501 sends a Y-direction switching signal to the multiplexers 502 and 503, selects the Y-direction pulse current generator 510 and the Y-direction second coil 17, and in the same manner as above, the Y-direction position data of the input pen 3. Read in.

The X-coordinate value and the Y-coordinate value of the digital value thus obtained are temporarily stored in the memory in the microprocessor 501 and sent to the electronic computer 8. However, a signal indicating the start of measurement is issued. During that time, the measurement as described above is repeated and its value is updated.

The electronic computer 8 sends the X and Y coordinate values to the touch panel control circuit 6 and, if necessary, the liquid crystal display panel control circuit 7 to display them on the liquid crystal display panel 40. Further, as will be described later, when timing signals are transmitted from the touch panel 60 and the touch panel control circuit 6, the X and Y coordinate values at that point are
It is recognized as a coordinate value (designated coordinate value) corresponding to the position designated by the input pen 3.

In the embodiment, the X-direction first coil 13 and the Y-direction first coil 14 are used for generating the magnetostrictive vibration wave, and the X-direction second coil 16 and the Y-direction second coil 17 are used for detecting the magnetostrictive vibration wave. However, it may be reversed. In that case, a magnetostrictive vibration wave is generated immediately below the input pen 3 and the second coils 13 and 14 are generated.
The induced voltage is generated at.

As the shield plate 20, a non-magnetic metal, for example, a metal plate of aluminum, copper or the like, or a plate material made of an alloy resin with a non-magnetic metal deposited on the surface thereof is used.

The backlight 30 emits light by, for example, interposing a phosphor layer in which phosphor powder is dispersed in a high dielectric constant medium between a transparent planar electrode and a back electrode, and applying an AC voltage between the electrodes. Well-known electroluminescence (EL)
An illumination device utilizing (electroluminescence) is used. In addition,
The AC voltage is supplied from the power supply device 4.

The liquid crystal display panel 40 uses, for example, a well-known matrix type display cell in which liquid crystal is interposed between a plurality of intersecting horizontal electrodes and vertical electrodes, and is driven and controlled by a well-known liquid crystal display panel control circuit 7.

The touch panel 60 includes a transparent base film 61 such as a polyester film as shown in FIGS.
On the surface of a, indium oxide (InO ₃ ) and tin oxide (S
nO ₃ ) and the like, a conductive film 61 in which a plurality of strip-shaped transparent resistance layers (electrodes) 61b-1 to 61b-24 each having a width of about 10 to 15 mm are vapor-deposited in a substantially parallel manner with a predetermined interval therebetween.
The same base film 62a and electrode 62b-1
To 62b-16, the conductive film 62 including the electrodes 61b-1 to 61b-24 and the electrodes 62b-1 to 62b.
-16 are orthogonal to each other, and are opposed to each other through a transparent dot spacer 63 made of silicon resin or the like which is vertically and horizontally provided on the conductive film 62 at a predetermined interval, and is made to face this. It is sandwiched between 64 and a protective sheet 65 such as a polyester film, and is further surrounded by a frame 66 of a non-magnetic metal such as aluminum. The touch panel 60 is attached to the case 50 with a protective sheet 65 facing upward through a hinge 67. The dot spacer 63 is made of the conductive film 6
Alternatively, instead of the dot spacer 63, the electrodes 61b-1 to 61b-24 and 62b-1 to 6 may be provided.
A spacer having an opening corresponding to the intersection of 2b-16 may be used.

As shown in FIG. 13, the width of the electrode is 20 mm on average on the part A of the touch panel 60 that can be pressed by the hand holding the input pen 3 and the part B of the other hand that is pressed by the pen tip. It was set because it was more than a distance away,
The present invention is not particularly limited to this, and the point is that A and B are
It suffices that the part of and the switch matrix including C be completely separated and recognized.

The electrodes 61b-1 to 61b-24 and the electrode 62b-
The electrodes 1 to 62b-16 are normally separated from each other by the dot spacers 63 and do not conduct electricity, but when pressed from above the protective sheet 65 to the substrate 64 side with a finger or the input pen 3, the electrodes intersect at the pressed positions. 61b-1 to 61b-24 and the electrodes 62b-1 to 62b-16 are arranged in a matrix to form key switches 68-1 to 68-384. The electrodes 61b-1 to 61b-24 and the electrodes 62b-1 to 62b-16 are connected to the touch panel control circuit 6 via signal lines 69, respectively. The first
About FIG. 0 and FIG. 12, only the thickness direction is expanded and shown.

The touch panel control circuit 6 selects a switch including the coordinates detected by the tablet 10 and the tablet control circuit 5 in the touch panel 60, detects the timing when the input pen 3 touches the switch, and obtains the obtained coordinates. The timing signal generating means for generating a timing signal for specifying the coordinate value (designated coordinate value) corresponding to the position to be input among the values is constructed. FIG. 14 shows the configuration. In the figure, 601 is a microprocessor, 6
02 is an address decoder, 603-605 are latch circuits, 606, 6
07 is a decoder driver, 608 to 610 are multiplexers, 62
0 is a level determination circuit.

As described above, the tablet control circuit 5 causes the computer 8
When the X and Y coordinate values of the input pen 3 are sent to the microprocessor 601 via the
Is the position of the switch including the coordinate value of the input pen 3 from the positional relationship between the position coordinates of the tablet 10 and each switch of the touch panel 60 stored in advance, for example, 68-
Detecting 78, converting this into data (BCD code) corresponding to the position of the electrode of the touch panel 60, and latching circuit
603 to 605. Note that this data is sent to each latch circuit from the data bus, but at this time, the address decoder 602 selectively stores predetermined data in each latch circuit.

The data sent to the latch circuit 603 is the decoder driver 6
A high level (+ 5V) voltage is applied to a selected one of the electrodes 62b-1 to 62b-16, here 62b-4, decoded at 06 and 607. On the other hand, the latch circuits 604 and 6
The data sent to 05 is decoded by the multiplexers 608 to 610, and the selected one of the electrodes 61b-1 to 61b-24, here 61b-6, is connected to the level determination circuit 620.

The level determination circuit 620 includes an operational amplifier 621, a reference voltage source 622,
When the input voltage is equal to or lower than the reference voltage V _T , a low level (OV) signal is output and the reference voltage V _T
When the above voltage is input, a high level signal is output.

At this time, even if the switches other than the selected switches 68-78 are pressed by the hand holding the input pen 3 or the like and the conduction occurs, the input voltage remains at the low level.
When the input pen 3 is pressed, a high level voltage is input to the level determination circuit 620, and accordingly, the level determination circuit 620
A higher level signal, that is, a timing signal is output. This timing signal is sent from the microprocessor 601 to the electronic computer 8.

When the electronic computer 8 receives the timing signal, the tablet 10 and the tablet control circuit 5 at that time point are received.
The X and Y coordinate values from are recognized as the designated coordinate values.

When the input pen 3 is moved, the position of the selected switch on the touch panel 60 also changes accordingly, and only the position pressed by the input pen 3 is recognized by the electronic computer 8 as the designated coordinate value.

Further, the designated coordinate values can be displayed on the liquid crystal display panel 40 as they are, or after being subjected to predetermined program processing.

Therefore, the handwriting of characters and figures written by the input pen 3 on the input / output panel 1 can be displayed in the same handwriting on the liquid crystal display panel 40 by optical display, and this display is performed by the translucent touch panel 60. Visible through.
At this time, by operating the backlight 30, a clear display can be obtained even in the dark surroundings, and the shield plate 2
With 0, noise can be blocked and the position detection accuracy does not deteriorate. Further, the touch panel 60 is lifted upward, and forms such as figures are drawn between the liquid crystal display panel 40 and the touch panel 60, and the touch panel 60 is inserted.
By tracing the figure or the like from above, the position of the figure or the like can be easily input. Further, the input result is displayed on the liquid crystal display panel 40 in the same manner as described above when the forms are removed.

Although the touch panel is translucent in the above embodiment, it may be opaque with conductive rubber sandwiched between the electrodes. However, in this case, it is not possible to display an image on the display panel or sandwich the form under the touch panel.

FIG. 15 shows a second embodiment of the present invention, in which an example in which a touch panel and a liquid crystal display panel are integrated is shown. In the figure, reference numerals 41 and 42 denote transparent substrates made of a plastic film or the like, and a large number of well-known horizontal electrodes 43 and vertical electrodes 44 are provided on the surfaces facing each other, and a liquid crystal 45 is enclosed between them. There is. Also,
Reference numerals 46 and 47 denote a pair of polarizing plates provided on both outer sides of the transparent substrates 41 and 42, and electrodes 62b-1 to 62b-16 of the touch panel 60 are provided on the upper surface of the upper polarizing plate 46.
(However, only one of them is shown in the drawing.) Is vapor-deposited, and a dot spacer 63 is further provided. Further, the conductive film 61 and the protective sheet 65 are provided on the electrodes 62b-1 to 62b-16 via the dot spacers 63. Therefore, according to this embodiment, the base film and the base substrate on the lower side can be omitted as compared with the above-described embodiments, the configuration is simpler, and the reduction of the display light from the liquid crystal display panel 40 is reduced. It is possible and can make a clearer display. Incidentally, the light transmittance of one conductive film is about 80%, which corresponds to this in the case of the present embodiment, but in the above-mentioned embodiment, this is two, and the transmittance is about 64%. Become.

FIG. 16 shows another example of the tablet. The tablet 70 has a shield plate 710 from above as shown in FIG.
a, magnetic plate 720a, 720b, conductor plate 730a, 730b, magnetic plate 720
c, 720d, conductor plates 730c, 730d, magnetic plates 720e, 720f, and shield plate 710b.

As the shield plates 710a and 710b, a printed board in which a copper plate 712 is adhered to one surface of an insulating substrate 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 in parallel, 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 takes a value of 0 to 1) is suitable.

The 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 both ends (17 in the illustrated example). It will be.

Between the magnetic plates 720a and 720b, between 720c and 720d, and 720e,
The 720f are bonded and fixed by thermocompression bonding, and the other substrates are bonded and fixed via a bonding sheet. At this time, the magnetic plate 720
a, 720c, 720e magnetic material is Y direction, magnetic material plate 720b, 720
The magnetic materials of d and 720f are arranged along the X direction, and the conductor plate 730
Conductors a, 730c are orthogonal to the Y direction, conductor plates 730b, 7
The conductor of 30d is 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, conductor plate 73
It is also possible to create a set of 0b, the magnetic plates 720c and 720d, the conductor plate 730c, and a set of the conductor plate 730d, the magnetic plates 720e and 720f, and the shield plate 710b, and further bond and fix them. The thickness of the entire tablet 70 is actually about 3 to 5 mm, but in the drawing, only the thickness direction is shown in an enlarged scale. In the tablet 70, the magnetic plates 720a, 72
Reference numerals 0b, 720e, and 720f are for forming a path of a magnetic flux generated around the excitation line by the magnetic material 721 therein to obtain a larger electromagnetic induction, and it is not necessary to provide them in particular. 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 conductor plates 730b of the excitation lines 740a to 740i are connected to the other ends of the adjacent excitation lines 740a to 740i on the side of the conductor plate 730d, that is, connected in series, and the other end of the excitation lines 740a and the excitation line 74 are connected.
The other end of 0i is connected to a drive current source in the position detection circuit 80 described later. The other ends of the detection lines 750a to 750h on the conductor plate 730b side are connected to the multiplexer 780, respectively, and the other ends of the detection lines 750a to 750h on the conductor plate 730d side 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 770a
The other ends of the conductor lines 730a to 770h on the conductor plate 730a side are 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. 17 is a circuit block diagram showing a specific configuration of the tablet control circuit 9 corresponding to the tablet 70. Less than,
The operation will be described in detail together with the description of each circuit block.

When the power of the tablet control circuit 9 is turned on, the driving current source is applied to the excitation lines 740a to 740i and 760a to 760i of the tablet 70.
A sine wave alternating current is applied from 901. At this time, the detection line 750
An induced voltage is generated in a to 750h and 770a to 770h by electromagnetic induction based on the alternating current flowing through the exciting wires 740a to 740i and 760a to 760i. This electromagnetic induction is applied to the magnetic plates 720a-72
Since it is performed via the magnetic body 721 of 0f, the larger the magnetic permeability of the magnetic body 721, the larger the voltage value of the induced voltage.

By the way, the magnetic permeability of the magnetic material 721 largely 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, but here it becomes maximum when a slight magnetic bias is applied, as shown in FIG. The more the magnetic bias is applied, the more it decreases.

When the tip of the input pen 3 is positioned above the magnetic body 721,
The magnetic flux emitted from the bar magnet 302 is substantially orthogonal to the magnetic body 721 immediately below the tip, and gradually follows the magnetic body 721 on both sides thereof. The amount of magnetic bias applied to the magnetic body 721 becomes larger as the angle at which the magnetic flux intersects the magnetic body 721 becomes smaller. Therefore, the magnetic bias amount becomes smallest immediately below the tip of the input pen 3 and gradually increases as the distance from the input pen 3 is increased.

Therefore, when the tip of the input pen 3 is applied to the input surface normally formed on the upper portion of the tablet 70, the magnetic bias amount applied to the magnetic body 721 immediately below the tip is set to the slight magnetic bias amount. Connect the tip of the input pen 3 to the detection line
When pressed to the position of the input surface at a distance x _s from the 750a in the X direction and a distance y _s from the detection line 770a in the Y direction, for example, the detection lines 750a to 750h in the X direction are as shown in FIG. Induction voltages V _{1 to} V ₈ that gradually decrease with distance from the designated position are generated with the voltage value generated on the detection line closest to the position (designated position) where the input pen 3 is placed as the maximum value. In FIG. 19, the horizontal axis represents the detection lines 750a to 750h.
Indicates the coordinate position in the X direction with the positions of x ₁ to x ₈ respectively, and the vertical axis indicates the voltage value.

On the other hand, at this time, when a measurement start command signal is sent from the electronic computer 8 to the arithmetic processing circuit 902 at this time, the arithmetic processing circuit 902 causes the multiplexer 780 via the output buffer 903.
A control signal is sent to the amplifier 904 to sequentially input the induced voltage of the detection lines 750a to 750h in the X direction. The induced voltages are amplified by an amplifier 904, rectified by a detector 905 and converted into a DC voltage, and further an analog-digital (A / D) converter 906.
Is converted into a digital value at and is sent to the arithmetic processing circuit 902 via the input buffer 907. The arithmetic processing circuit 902 temporarily stores the induced voltages (digital values) in the memory 908, and obtains the coordinate value x _s in the X direction from them.

Although various methods of calculating the coordinate value x _s are possible, the induced voltage is approximated to the induced voltage near the maximum value by paying attention to the fact that the voltage directly below the input pen 3 has a maximum value and decreases on both sides thereof. There is a method of obtaining a function and obtaining a coordinate value x _s as the coordinate of the maximum value of the function. Here, for example, each detection line
The interval of 750a to 750h is Δx, and the coordinate x in FIG.
_{When 3} to the coordinate x ₅ is approximated by a quadratic function (shown by a solid line in the figure), it can be calculated as follows. First, V ₃ = _a than the voltage coordinate value of each detection line ^{_{(x 3 -x s) 2 +}} b ... (1) V 4 = a (x 4 -x s) 2 + b ... (2) V 5 = a ( ^{_{x 5 -x s) 2 + b}} ... becomes (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 , and V ₅ induced in the above and the coordinate value x ₃ (known) of the detection line 750c (known).

The arithmetic processing circuit 902 first detects the induced voltage V _k having the maximum value (here, the maximum voltage value) from among the induced voltages. Further, the arithmetic processing circuit 902 reads the induced voltage V _k and the induced voltages V _k−1 , V before and after the induced voltage V _k from the memory 908.
_{The k + 1} is taken out, and these are used as the voltages V ₃ , V ₄ , and V _{5 in the} equation (6), respectively, and the arithmetic processing of the equation (6) is performed to obtain the X coordinate value x _s .

Next, the arithmetic processing circuit 902 sends a control signal to the multiplexer 790 via the output buffer 903, and the detection lines 770a to 770a-7
Sequentially inputs the induced voltage of 70h, obtains the Y-coordinate value y _s performs processing similar to that described above.

The X and Y coordinate values of the digital value thus obtained are temporarily stored in the memory 908 and sent to the electronic calculator 8. While the signal indicating the measurement start is being issued,
The above-mentioned measurement and calculation are repeated every predetermined time,
Its value is updated.

In the electronic computer 8, similarly to the above, the X and Y coordinate values are sent to the touch panel control circuit 6 and, if necessary, sent to the liquid crystal display panel control circuit 7 and displayed on the liquid crystal display panel 40. In addition, as described above, when the timing signal is transmitted from the touch panel 60 and the touch panel control circuit 6, the X and Y coordinate values at that time are input as the designated coordinate values.

FIG. 20 shows a concrete example of the drive current source 901.
In the figure, reference numeral 901a denotes an integrating circuit, which is an arithmetic processing circuit 90.
The clock pulse of 2 (or a pulse obtained by dividing this) is used as an input signal, which is integrated and converted into a triangular wave signal.
Reference numeral 901b is a NAND pass filter, which converts the triangular wave signal into a sine wave signal. A power driver 901c 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 for synchronization with the tablet control circuit 9.

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.
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.

Although the liquid crystal display panel is used as the flat display in the above-mentioned embodiment, the invention is not limited to this, and a plasma display panel, an EL display panel, or the like may be used.

(Effect of the Invention) As described above, according to the present invention, the coordinate value of the position on the tablet to which a stationary magnetic field is applied from the substantially rod-shaped position specifying magnetic generator that can be moved to an arbitrary position, In a position detecting device for repeatedly detecting while the strength of the magnetic field is above a certain level, a portion of the tablet having a substantially rod-shaped position specifying magnetic generator on the tablet and the substantially rod-shaped position. The touch panel having a switch matrix structure composed of a large number of substantially rectangular switches each having a side length smaller than the average distance between one end of the designated magnetic generator and the portion in contact with the tablet is stacked, and The coordinates obtained by selecting a switch including the detected position in the touch panel and detecting the timing at which the substantially bar-shaped position specifying magnetic generator contacts the switch. Since the timing signal generating means for generating the timing signal for specifying the coordinate value corresponding to the position to be input among the values is provided, it is possible to obtain it by simply pressing the substantially rod-shaped position specifying magnetic generator on the touch panel. It is possible to extract a timing signal for specifying the coordinate value corresponding to the position to be input among the coordinate values, and therefore, a transmitter for sending a conventional timing signal to the position specifying magnetic generator, There is no need to provide a signal generation circuit, battery, etc., and it can be operated like a normal writing instrument with a natural feeling, and a timing signal is extracted from only the switch including the detected position in the switch matrix that constitutes the touch panel. The timing signal is not output even when a hand other than the position specifying magnetic generator touches the touch panel. There is no possibility that the coordinate value is input.
Further, according to the one in which a flat type display panel is superposed on the tablet, a translucent touch panel having the same switch matrix configuration is superposed on it, and the same timing detecting means is provided, There are advantages such as being able to operate while displaying input characters and figures.

[Brief description of drawings]

The drawings show an embodiment of the position detecting device of the present invention,
FIG. 1 is a perspective view showing a basic structure, FIG. 2 is an enlarged cross-sectional view with a part omitted showing a schematic structure of an input / output panel 1, FIG. 3 is a block diagram showing a schematic structure of a control device 2, and FIG. Is a sectional view of the input pen 3, FIG. 5 is a plan view showing the structure of the tablet 10, FIG. 6 is a sectional view taken along line VI-VI of FIG. 5, and FIG. 7 is a characteristic of magnetic bias vs. electromechanical coupling coefficient. FIG. 8 and FIG. 8 are block diagrams of the tablet control circuit 5, and FIG.
FIG. 10 is a diagram showing an example of a temporal change of the induced electromotive force generated in the coil 16, FIG. 10 is an exploded perspective view of a main part of the touch panel 60, FIG. 11 is an enlarged perspective view of the touch panel 60, and FIG. 14 is a cross-sectional view of a main part of FIG. 13, and FIG. 13 is an explanatory view showing the relationship between the hand holding the input pen 3 on the touch panel and the other hand and the position of the pen tip of the input pen 3, FIG.
FIG. 15 is a block diagram of the touch panel control circuit 6, FIG. 15 is a schematic perspective view showing a second embodiment of the present invention, FIG. 16 is a diagram showing a specific structure of another tablet 70, and FIG. 18 is a block diagram of the tablet control circuit 80, FIG. 18 is a characteristic diagram of magnetic bias vs. permeability, FIG. 19 is a graph showing an example of an induced voltage generated in each detection line in the X direction, and FIG.
The figure is an electric circuit diagram showing a specific example of the drive current source 81. 1 ... Input / output panel, 2 ... Control device, 3 ... Input pen, 4 ...
Power supply device, 5 ... Tablet control circuit, 6 ... Touch panel control circuit, 7 ... Liquid crystal display panel control circuit, 10
… Tablet, 40… Liquid crystal display panel, 60…
Touch panel.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Tsuguya Yamanami 1342-3 Tohokudori, Sugaya, Ageo City, Saitama Prefecture Wacom Co., Ltd.

Claims (3)

[Claims] 1. A coordinate value of a position on a tablet to which a stationary magnetic field is applied from a substantially rod-shaped position-designating magnetic generator that can be moved to an arbitrary position while the strength of the magnetic field is above a certain level. In a position detecting device for repeatedly detecting, a portion of the tablet having the substantially rod-shaped position specifying magnetic generator touches the tablet and one end of the substantially rod-shaped position specifying magnetic generator contacts the tablet. A touch panel having a switch matrix structure composed of a large number of substantially square switches each having a side length smaller than the average distance between the touch panel and the switch, and a switch including the detected position in the touch panel. Is selected, and the timing at which the substantially rod-shaped position specifying magnetic generator contacts the switch is detected, and the position corresponding to the position to be input of the obtained coordinate values is detected. Position detecting device characterized by providing a timing signal generating means for generating a timing signal for specifying the target value. 2. A coordinate value of a position on a tablet to which a stationary magnetic field is applied by a substantially rod-shaped position specifying magnetic generator that can be moved to an arbitrary position while the strength of the magnetic field is above a certain level. In a position detecting device for repeatedly detecting, a flat display panel is superposed on the tablet, and a portion having a hand of the substantially bar-shaped position specifying magnetic generator on the tablet and a part of the bar which are in contact with the tablet. A translucent touch panel having a switch matrix configuration composed of a large number of substantially rectangular switches each having a side length smaller than the average distance between one end of the position specifying magnetic generator and the portion in contact with the tablet. Timing at which the switch including the detected position in the touch panel is selected while being overlapped, and the switch is contacted by the substantially rod-shaped position specifying magnetic generator Detecting and position detecting device characterized by providing the timing signal generating means for generating a timing signal for specifying the coordinate values corresponding to the position to be input among the obtained coordinate values. 3. The position detecting device according to claim 2, wherein the touch panel and the display panel are integrated.