JPH0762819B2 - Position detector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention will be described in the following order.

A Industrial field of use B Outline of the invention C Conventional technology D Problems to be solved by the invention E Means for solving problems F Action G Example G-1 Position detection plate unit (Fig. 1, Fig. 1 2) G-2 voltage detecting means (FIGS. 1 and 2) G-3 output signal forming circuit section (FIGS. 1 and 2) G-4 Modification H Effect of the invention A Industrial field of application The present invention relates to a position suitable for use in constructing a portion including a tablet plate and a stylus in a graphic display or creating device or the like in which the position of the stylus on the tablet plate is sequentially detected to obtain data such as a graphic. Regarding a detection device.

B. Summary of the Invention The present invention provides a drive circuit unit for performing voltage or current supply scanning for sequentially supplying a predetermined voltage or current to a plurality of strip conductors in a position detection plate in which a plurality of strip conductors are arranged according to the arrangement order. The detection means placed on the position detection plate is used to obtain a detection output signal corresponding to the position of one of a plurality of strip conductors to which a voltage or current is applied, and detection is performed based on this detection output signal. In a position detection device for obtaining a position detection output representing the position on the position detection plate of the means,
From the drive circuit section, through the control signal deriving section, a start signal is output at the start time of the voltage or current supply scan or at a predetermined time point thereafter, and an end signal at the end time of the voltage or current supply scan or at a predetermined time point thereafter. The effective detection period is the period from the time of the start signal to the time of the end signal, and the position detection output is obtained from the detection output signal obtained during this effective detection period. The output signal forming circuit unit for obtaining the detection output can be made common to a plurality of position detecting plate units formed by including position detecting plates of different scales and drive circuit units accompanying it, Also, the configuration is simplified.

C Conventional technology When a figure or the like is drawn on a tablet board by a stylus, a figure display device or figure creating apparatus is provided in which the position of the stylus on the tablet board is sequentially detected to obtain data of the figure or the like. In the device, a position detecting device used as a part that includes a tablet plate and a stylus has a position detecting plate that forms the tablet plate and a stylus whose position on the position detecting plate is detected. However, as one of the types, a stylus position is detected by an electrostatic method, for example, Japanese Patent Laid-Open No. 59-87583.
It is proposed as described in Japanese Patent Publication.

In such a position detecting device, for example, the position detecting plate constituting the tablet plate is configured such that a plurality of strip conductors are arranged at a constant interval, and the plurality of strip conductors are arranged at a constant time interval. The driving circuit unit performs voltage supply scanning in which a constant voltage is sequentially supplied in the order of arrangement, and the stylus is composed of voltage detection means for generating an output signal according to the position of the strip conductor to which the voltage is applied. Then, the position of the plurality of strip conductors in the arrangement direction on the position detecting plate forming the tablet plate of the voltage detecting means is detected by the output signal of the voltage detecting means forming the stylus.

The voltage detecting means is specifically configured by including an electrode grounded via a fixed capacitance, and the magnitude of the voltage detected by this electrode is the position of the strip conductor to which the voltage is applied with respect to the voltage detecting means. When a constant voltage is sequentially supplied to the plurality of strip conductors in the order of their arrangement at a constant time interval, the detection output signal from the voltage detecting means outputs a constant voltage at every constant time interval. It takes a maximum level when a voltage is applied to the strip conductor that is changed stepwise and is closest to the voltage detecting means, and as a whole, for example, changes from zero to a certain positive value, and again from this certain positive value. It will return to zero.
Then, from the reference time point, for example, the start time point of the voltage supply scan to the position detection plate, the detection output signal of the voltage detection means passes through a predetermined bandpass filter, and the level of the output signal reaches a predetermined level, or Then, the time required until the point of crossing a specific level thereafter corresponds to the position in the arrangement direction of the plurality of strip conductors on the position detection plate of the voltage detection means. Therefore, the detection output signal from the voltage detecting means is appropriately processed to form a position detecting signal corresponding to the above-mentioned required time, and based on the position detecting signal, the position detecting plate of the voltage detecting means is detected. The positions of the plurality of strip conductors in the arrangement direction are detected.

In such a position detection device, in forming the position detection signal corresponding to the above-described required time, for example, an output signal forming circuit unit including a counter is used, and the counter is
An output obtained by starting the measurement at the same time as the start of the voltage supply scan to the position detection plate or at a predetermined delay time with respect to the start of the voltage supply scan and outputting the detection output signal of the voltage detection means through a predetermined band pass filter. The time length of the above-described required time is measured by controlling the measurement so that the measurement is ended when the signal level reaches a predetermined level or when the signal level crosses a specific level thereafter. Then, after the counter starts measuring, for example, the voltage detection means is placed at a position outside the effective detection range on the position detection plate, and the detection output signal of the voltage detection means is obtained through a predetermined bandpass filter. When the output signal is not obtained, the time length is set when the count value of the counter exceeds the maximum count value set in advance for the counter, which is determined by the scale of the position detection plate, and the counter overflows. It is supposed to end the measurement.

D Problems to be Solved by the Invention However, in the output signal forming circuit section in which the counter is controlled as described above, the setting of the measurement start time point for the counter is set according to the scale of each position detection plate. Therefore, it is necessary to set the maximum count value for detecting the overflow state, and therefore, a plurality of position detection plate units formed by including the position detection plates of different scales and the drive circuit section associated therewith. However, the output signal forming circuit unit cannot be shared, and further, it corresponds to a plurality of position detecting plate units formed by including position detecting plates of different scales and drive circuit units accompanying them. It becomes difficult to use a general-purpose integrated circuit component in the output signal forming circuit section, and the output signal forming circuit section is diversified, resulting in an increase in cost.

In view of such a point, the present invention provides a plurality of strip conductors from the detection means placed on the position detection plate when a voltage or a current is sequentially supplied to the plurality of strip conductors of the position detection plate according to the arrangement order. A detection output signal corresponding to the position of the one to which the voltage or current is applied is obtained, and the position detection output is obtained based on this detection output signal,
An output signal forming circuit section for obtaining a position detection output based on a detection output signal from the detecting means has a plurality of positions formed by including position detecting plates of different scales and a drive circuit section accompanying it. It is an object of the present invention to provide a position detecting device which can be commonly used for a detecting plate unit and which can be simplified in structure and can be obtained at low cost.

E Means for Solving the Problems In order to achieve the above-mentioned object, the position detecting device according to the present invention includes a position detecting plate in which a plurality of strip conductors are arranged in parallel at a predetermined interval, and a plurality of thin detecting conductors. A drive circuit section for performing a voltage or current supply scan for supplying a predetermined voltage or current to the strip conductors in order of their arrangement, and the drive circuit section supplies the strip conductors immediately after the start of the voltage or current supply scan. A start signal is obtained based on a predetermined voltage or current that is supplied or a predetermined voltage or current that is supplied to a predesignated one of the plurality of strip conductors, and the voltage or current is output from the drive circuit unit. A predetermined voltage or current supplied to the strip conductor immediately before the end of the supply scan, or a predetermined voltage or current supplied to the strip conductor immediately before the end of the voltage or current supply scan. Alternatively, a control signal derivation unit that obtains an end signal based on the voltage or current formed by delaying the current and a voltage or current of a plurality of strip conductors when applied to the position detection plate However, the start signal and the end signal from the control signal deriving unit are supplied in addition to the detection output signal from the detection means and the detection output signal from the detection means. An output signal forming circuit section that obtains a position detection output indicating the position of the detection means on the position detection plate based on the detection output signal obtained from the detection means during the effective detection period with the period up to the time point as the effective detection period. Configured.

F Action In the position detecting device according to the present invention as described above, based on the voltage or current supplied to the strip conductors from the drive circuit unit that performs the voltage or current supply scanning to the plurality of strip conductors of the position detection plate. The start signal and the end signal obtained by the control signal deriving unit are supplied to the output signal forming circuit unit, and in the output signal forming circuit unit, the detection output signal from the detecting means placed on the position detection plate from the time of the start signal. The time length until the time when the predetermined state is obtained is detected, and the position detection output indicating the position of the detection means on the position detection plate is obtained based on the time length. Then, after the start signal is supplied to the output signal forming circuit section, if the predetermined state in the detection output signal from the detecting means is not obtained, at the time when the end signal is supplied to the output signal forming circuit section, The position detection operation ends automatically. That is, the start signal and the end signal define the effective detection period for the output signal forming circuit unit, and the output signal forming circuit unit forms the position detection output based on the detection output signal obtained from the detecting means in the effective detection period.

As described above, the start signal and the end signal derived by the control signal deriving unit are obtained based on the voltage or the current supplied from the drive circuit unit to the strip conductor, so that the drive circuit unit In addition to simplifying the configuration, the output signal forming circuit section does not need to be separately set, and therefore, a plurality of positions including the position detection plate of different scale and the accompanying drive circuit section are provided. It can be shared with the detection plate unit,
In addition, the structure can be simplified.

G Embodiment G-1 Position detection plate unit (FIGS. 1 and 2) FIG. 1 shows an example of the position detection device according to the present invention. First, a position detection plate and a drive circuit section accompanying it are shown. The position detection plate unit including it will be described.

In this example, the position detection plate that constitutes the tablet plate
10, strip conductors Y ₁ on the insulating layer 11, together with Y ₂ · · · Ym are arranged in parallel at regular intervals, strip conductors Y ₁ to the insulating layer 11 through the insulating layer value 12 ~ Strip conductor X ₁ , X orthogonal to Ym
₂ ... Xn are arranged in parallel at regular intervals, and although not shown in the drawing, an insulating layer is further deposited on the insulating layer 12 to form a structure.

The strip conductors X _{1 to} Xn and the strip conductors Y _{1 to} Ym of this position detection plate 10
At one end of the switch circuit, which forms part of the drive circuit
32 n of switches 32 ₁ , 32 ₂ ... 32 n and switches 34 ₁ , 34 ₂ ... 34 m of the switch circuit 34 are provided respectively. Then, within a predetermined period, pulse signals are sequentially supplied to the switches 32 _{1 to} 32n from the output terminals N ₁ , N ₂ ... Nn of the shift register 31 which also forms a part of the drive circuit section at regular time intervals. Then, the switches 32 _{1 to} 32 n are sequentially switched from the terminal A side to the terminal B side for a fixed time, so that the strip conductors X _{1 to} Xn are sequentially driven to a constant positive voltage from the power supply terminal 35 for a fixed time. Voltage + Vcc is supposed to be applied. Further, within a predetermined period different from this, similarly, the output terminals M ₁ and M of the shift register 33 forming a part of the drive circuit are similarly provided.
₂ ... The pulse signals are sequentially supplied from Mm to the switches 34 ₁ to 34 m at a constant time interval, and the switches 34 _{1 to} 34 m are sequentially switched from the terminal A side to the terminal B side at a constant time interval. Power supply terminal 35 for each fixed time on the strip conductors Y _{1 to} Ym
More constant positive voltage + Vcc is sequentially applied.

On the other hand, from the clock pulse generation circuit 41, for example, 2400 kH
A basic clock pulse Co of z is obtained, and this clock pulse Co is supplied to the frequency dividing circuit 42 and is frequency-divided.
Clock pulse Cs as shown in Fig. 2 set to kHz
Is obtained. This clock pulse Cs is supplied to the signal generating circuit 43 and has a cycle corresponding to the unit detection periods Tx and Ty as shown in FIG. 2 from the signal generating circuit 43, and a pulse corresponding to one cycle of the clock pulse Cs. Detection start signal with width
Sp and, for example, the drive start signal St delayed by one cycle of the clock pulse Cs with respect to this detection start signal Sp
A detection period identification signal Sxy whose level is inverted every cycle of the detection start signal Sp, a signal Stx composed of pulses in a period Tx in which the detection period identification signal Sxy of the drive start signal St is at a high level, and A signal Sty including a pulse in the period Ty in which the detection period identification signal Sxy in the start signal St is at a low level is obtained.

Then, the clock pulse Cs is supplied to the shift register 31 as a shift pulse, and the signal Stx is supplied to the shift register 31 as a start pulse, and the period of the clock pulse Cs is n cycles from the leading edge of the signal Stx in the period Tx. In the drive period until the time of time elapses, as shown in FIG. 2, the output terminals N _{1 to} Nn of the shift register 31 each have a pulse signal P _x1 having a pulse width of one cycle of the clock pulse Cs. , P _x2 ... Pxn is 1 of the clock pulse Cs
These pulse signals are obtained in sequence for each unit time Ts of the cycle.
P _x1 ~Pxn is supplied to the switch 32 ₁ ～32N switch circuit 32, as described before, a strip conductor X ₁ to Xn voltage + Vcc of the power source terminal 35 are sequentially supplied to, strip conductors X ₁ ~ The voltage supply scan for Xn is performed with a state in which it starts at the time of the leading edge of the signal Stx, sends the pulse signal P _x1 immediately after the start thereof, and ends immediately after sending the pulse signal Pxn.

Similarly, the clock pulse Cs is supplied to the shift register 33 as a shift pulse, and the signal Sty is supplied to the shift register 33 as a start pulse, so that m cycles of the clock pulse Cs from the time point of the leading edge of the signal Sty within the period Ty. During the driving period until the time of minutes elapses, the output terminals M _{1 to} Mm of the shift register 33 each have a pulse signal P _y1 having a pulse width of one cycle of the clock pulse Cs, as shown in FIG. , P _y2・ ・ ・ Pym is 1 of the clock pulse Cs
These pulse signals are obtained in sequence for each unit time Ts of the cycle.
P _{y1 to} Pyn are supplied to the switches 34 _{1 to} 34m of the switch circuit 34, and as described above, the voltage + Vcc from the power supply terminal 35 is sequentially supplied to the strip conductors Y ₁ to Ym, and the strip conductor Y _{1 to} Pm. The voltage supply scan for Ym is performed in a state where it starts at the time of the leading edge of the signal Sty, sends the pulse signal P _y1 immediately after the start thereof, and ends immediately after sending the pulse signal Pym.

G-2 Voltage detecting means (Figs. 1 and 2) The voltage detecting means 20 forming a stylus for drawing a figure on the position detecting plate 10 forming the tablet plate is the detection electrode 20 '.
This detection electrode 20 'has its head exposed to the outside of the grounded shield case 21 and a position detection plate.
It is placed on top of and is either fixed inside the shield case 21 or grounded via a capacitance C _L formed between it and the shield case 21. Furthermore, the detection electrode 2
0 ′ is connected to the gate of the field effect transistor 22 inside the shield case 21, and
A bias resistor Rr is connected between the gate of the and the ground.

Then, within the period Tx or Ty, the strip conductors X _{1 to} Xn
Alternatively, voltage + Vc can be applied to the strip conductors Y _{1 to} Ym in sequence for a fixed time.
The signal obtained at the detection electrode 20 'as the capacitance formed between the strip conductor to which the voltage + Vcc is applied and the detection electrode 20' is sequentially changed at a constant time interval. and the level change of the voltage Vo, when the strip conductor X ₁ to Xn or strip conductor Y ₁ closest ones to the voltage + Vcc to the position of the detection electrode 20 'of the ~Ym is given, the level of the signal voltage Vo It will be maximum. The signal voltage Vo obtained at the detection electrode 20 'is impedance-converted by the field effect transistor 22, and the tuning frequency forming the bandpass filter, that is, the center frequency of the passband is, for example, 7.5 kHz. Is supplied to.

G-3 Output Signal Forming Circuit Section (FIGS. 1 and 2) From the tuning amplifier circuit 51 to which the signal voltage Vo from the voltage detecting means 20 is supplied, the signal voltage Vo as shown in FIG. At two time points, which are delayed by a predetermined time from the time point when the maximum value is reached, a signal that changes so as to cross the ground level from the positive direction to the negative direction after having a large level peak portion, respectively, is Scx during the period Tx.
, And as Scy in the period Ty.
These signals Scx and Scy are the Schmitt trigger circuit.
2, the signals Scx and Scy fall from a high level to a low level when the signals Scx and Scy exceed a certain positive voltage threshold Vs, and then the signals Scx and Scy are supplied.
A signal Sz rising from a low level to a high level is obtained when cy crosses the ground level from the positive direction to the negative direction.

Then, the drive start signal St from the signal generation circuit 43 is supplied to the set terminal S of the RS flip-flop circuit 53, and the signal Sz obtained from the Schmitt trigger circuit 52 is supplied to the reset terminal R of the RS flip-flop circuit 53. Been RS
The flip-flop circuit 53 rises at the rising edge of the drive start signal St, and thereafter, in each period Tx or Ty, the signal Scx or Scy from the tuning amplifier circuit 51 is first changed from positive to negative after exceeding the voltage threshold Vs. The time tx or ty at which the ground level is crossed in the direction. A signal Gc is obtained, as shown in FIG. 2, which falls at the first rising edge of the signal Sz indicated by the upward arrow.

On the other hand, the pulse signal P _x2 obtained from the second output terminal N ₂ of the shift register 31 or the pulse signal P _y2 obtained from the second output terminal M ₂ of the shift register 33 is
The signal is derived as a start signal Ss via an OR gate circuit 60 forming a control signal derivation unit, and is supplied to the set terminal S of the RS flip-flop circuit 58. In addition, the pulse signal Px obtained from the output terminal Nn at the end of the shift register 31
n, or a pulse signal Pym obtained from the output terminal Mm at the end of the shift register 33 is derived as an end signal Se via an OR gate circuit 61 and a delay circuit 62 which also form a control signal deriving unit, and It is supplied to the reset terminal R of the gate circuit 58. At this time, as shown in FIG. 2, the pulse signal Pxn or Pym is delayed by the delay circuit 62 by the time T ₁ to become the end signal Se, and the delay time T ₁ in the delay circuit 62 is determined by the voltage detection means 20. As a result of the signal processing in the internal circuit, the tuning amplifier circuit 51, the Schmitt trigger circuit 52, etc., it corresponds to the total delay time when the first rising edge shown by the upward arrow of the signal Sz is obtained, and each period Tx Or at Ty, end signal
The falling edge of Se is selected to be before the leading edge of the detection start signal Sp.

As a result, the RS flip-flop circuit 58 rises at the trailing edge of the start signal Ss, that is, the pulse signal P _x2 or P _y2 , and falls at the rising edge of the end signal Se, as shown in FIG. , The signal Gb is obtained.

And 2400kH obtained from the clock pulse generation circuit 41
The clock pulse Co of z, the signal Gc obtained from the RS flip-flop circuit 53, and the signal Gb obtained from the RS flip-flop circuit 58 are supplied to the AND gate circuit 54,
A period in which both the signals Gc and Gb are at a high level, that is, the start signal Ss in the period Tx, that is, from the time t _2x at the trailing edge of the pulse signal P _x2 to the time tx at the falling edge of the signal Gc, or the period Ty. In the period from the start signal Ss at, that is, the time t _2y at the trailing edge of the pulse signal P _y2 to the time ty at the falling edge of the signal Gc, the clock pulse Co is extracted.

Then, the detection start signal Sp is the clear terminal CLR of the counter 55.
To the signal Gc obtained from the RS flip-flop circuit 53 and the signal obtained from the RS flip-flop circuit 58 after the counter 55 is cleared.
While both Gb are at high level, the clock pulse Cc obtained from the AND gate circuit 54 is
Is supplied to the clock terminal CK of and is counted. This causes the counter to be at 55 at time t _{2x in the} period Tx.
The measurement of the clock pulse Cc is performed in the period up to the time tx from and the time length from time point t _2x to time tx is measured, output data corresponding to the time length can be obtained and the period Ty
In the measurement of the clock pulse Cc is performed in a period from time t _2y to time ty, and the time length from time point t _2y to time ty is measured, output data corresponding to the time length is obtained.

Here, the time point t _2x and the time point t _2y are the period Tx and the time period, respectively.
Of the strip conductors X ₂ and Y ₂ in Ty, that is, the _{second of} the strip conductors X _{1 to} Xn arranged in the X direction and the strip conductors Y _{1 to} Ym arranged in the Y direction. Is the time when the voltage supply to the second one of the
Is a reference time point relating to the voltage supply to the strip conductors X _{1 to} Xn and Y _{1 to} Ym. When the detection electrode 20 'is placed on the strip conductor X ₁ , the falling time point tx of the signal Gc obtained in one period Tx is after the time point t _2x , and the detection electrode 20' is Falling time ty of signal Gc obtained in one period Ty when placed on conductor Y ₁
Is supposed to be after time t _2y .

Therefore, the time length from the time point t _2x to the time point tx in the period Tx, and therefore the output data of the counter 55 corresponding to this time length, is the fine data arranged in the X direction on the position detection plate 10 of the detection electrode 20 ′. Standard _{one of the} strip conductors X _{1 to} Xn (1
The distance from the second strip conductor X ₁ ), that is, the position in the X direction, and the time t in the period Ty.
Time length from _2y to time ty, therefore, output data of the time length counter 55 corresponding to, among the strip conductors Y ₁ ～Ym arranged in the Y direction on the position detection plate 10 of the detection electrode 20 ' Distance from the standard one (first strip conductor Y ₁ ),
That is, it corresponds to the position in the Y direction. As a result, the counter 55 makes the RS in the middle of every other period Tx.
In the period from the fall of the signal Gc obtained from the flip-flop circuit 53 to the leading edge of the detection start signal Sp thereafter, the contents indicating the position of the detection electrode 20 'on the position detection plate 10 in the X direction at that time. Output data of the RS flip-flop circuit 53 in the middle of every other period Ty.
In the period from the fall of the obtained signal Gc to the leading edge of the subsequent detection start signal Sp, the detection electrode 2 at that time is
The output data having the content indicating the position in the Y direction on the position detection plate 10 of 0'is held.

Further, the detection start signal Sp is supplied to the reset terminal R of the RS flip-flop circuit 56, and the Schmitt trigger circuit
The signal Sz obtained from 52 is supplied to the set terminal S of the RS flip-flop circuit 56,
From 56, the output of the counter 55 indicates the position of the detection electrode 20 'on the position detection plate 10 in the X direction or the Y direction, and the next detection start signal Sp A signal Da that is at a high level is obtained until the rising time.

Then, the detection period identification signal Sxy from the signal generation circuit 43
The output data of the counter 55 and the output data of the counter 55 obtained from the RS flip-flop circuit 56 have contents indicating the position of the detection electrode 20 'on the position detection plate 10 in the X direction or the Y direction. A signal Da indicating the period is supplied to the data processing circuit 57, which causes the data processing circuit 57 to detect the detection electrode.
A position data output indicating the position of the 20 'position detecting plate 10 in the X and Y directions is obtained.

Next, in the period Tx or the period Ty, for example, the voltage detection means 20 is placed at a position outside the effective detection range on the position detection plate 10, and the strip conductors X _{1 to} Xn or the strip conductors Y ₁ to
Even if the voltage supply scan for Ym is performed, the tuning amplifier circuit 51
From the symbol Scx or S with an amplitude exceeding the voltage threshold Vs
If cy cannot be obtained, Schmidt trigger circuit 52
The signal Sz from does not have a level change, and therefore the signal Gc from the RS flip-flop circuit 53 that rises at the time of rising of the drive start signal St does not fall and continuously takes a high level. Becomes

At this time, the counter 55 has an RS flip-flop circuit.
During the period from the time point t _2x to the time point tnx in the period Tx, or the time period from the time point t _2y to the time point tmy in the period Ty, in which the signal Gb from 58 is at the high level, the clock pulse Co is supplied through the AND gate circuit 54. It is supplied and measured, and the measurement is stopped at time t _2x or time t _2y , which is the time of the leading edge of the end signal Se. And in such cases, R
The signal Da from the S flip-flop circuit 56 does not take the high level, and the output data of the counter 55 indicates the position of the detection electrode 20 'on the position detection plate 10 in the X direction or the Y direction. Since this does not occur, the position detection operation in the period Tx or the period Ty ends without the position data output from the data processing circuit 57 being obtained.

In this way, the signal Sz obtained from the Schmitt trigger circuit 52 based on the signal voltage Vo from the voltage detection means 20.
RS flip-flop circuits 53, 56 and 58, an AND gate circuit 54, and a counter 5 which form a position data output according to
5 and the data processing circuit 57 and the like constitute an output signal forming circuit unit that forms a position detection output, and this output signal forming circuit unit, in addition to the signal Sz from the Schmitt trigger circuit 52, is an OR gate. The start signal Ss from the circuit 60 and the end signal Se from the delay circuit 62 are supplied, and the start signal Ss is supplied by the start signal Ss and the end signal Se.
The effective detection period from the time point of the leading edge of the end signal Se to the time point of the leading edge of the end signal Se is defined, and the position detection output based on the signal Sz obtained from the Schmitt trigger circuit 52 is formed in the effective detection period. .

G-4 Modified Example In the above example, the position detection plate unit including the position detection plate 10 and the switch circuits 32 and 34 and the drive circuit units including the shift registers 31 and 32, etc. Voltage detection is performed by supplying voltage + Vcc to the plurality of strip conductors X _{1 to} Xn and Y _{1 to} Ym of the detection plate 10 in sequence, and the voltage detection means 20 is arranged on the position detection plate 10 to detect the position. However, in the position detection device according to the present invention, the position detection plate unit including the position detection plate and the drive circuit section associated with the position detection plate is arranged in order on the plurality of strip conductors of the position detection plate. The current supply scan for supplying the current is performed, and the current detection means may be arranged on the position detection plate to detect the position, which can be configured in the same manner as in the above-described example.

H Effect of the Invention As is apparent from the above description, according to the position detecting device of the present invention, the position detection based on the detection output signal supplied to the output signal forming circuit section and obtained from the detecting means in the output signal forming circuit section. The start signal and the end signal that determine the effective detection period in which the operation of forming the output is performed do not require a separate setting in the output signal forming circuit section, and the voltage or current supply scan to the plurality of strip conductors of the position detection plate is performed. The control signal deriving unit obtains the voltage or current based on the voltage or current supplied from the drive circuit unit for performing the drive circuit unit to the drive circuit unit. Can be made common to a plurality of position detection plate units each having a position detection plate of a different scale and a drive circuit unit accompanying it. Become things, also be configured using a general purpose integrated circuit components, Hakare simplification of the structure, it shall can be obtained at low cost.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing an example of the position detecting device according to the present invention, and FIG. 2 is a waveform diagram used for explaining the operation of the example shown in FIG. In the figure, 10 is a position detection plate, 20 is voltage detection means, 20 'is detection electrodes, 31 and 33 are shift registers, 32 and 34 are switch circuits, 60 and 61 are OR gate circuits, 62 is a delay circuit, 52
Is a Schmitt trigger circuit, 53, 56 and 58 are RS flip-flop circuits, 54 is an AND gate circuit, 55 is a counter, 57 is a data processing circuit, and X _{1 to} Xn and Y _{1 to} Ym are strip conductors. .

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akio Sakano 6-735 Kita-Shinagawa, Shinagawa-ku, Tokyo Sony Corporation (72) Inventor Eiji Tamaru 6-35 Kita-Shinagawa, Shinagawa-ku, Tokyo Sony Corporation (56) References JP-A-55-83979 (JP, A)

Claims (1)

[Claims] 1. A position detecting plate in which a plurality of strip conductors are arranged in parallel at a predetermined interval, and an order of arrangement of the plurality of strip conductors at a predetermined time interval in each of the plurality of strip conductors. A drive circuit section for sequentially performing a voltage or current supply scan for supplying a predetermined voltage or current, and the predetermined voltage supplied from the drive circuit section to the strip conductor immediately after the start of the voltage or current supply scan. Alternatively, a start signal is obtained based on the current or the predetermined voltage or current supplied to a predesignated one of the plurality of strip conductors, and the voltage or current supply scan is performed from the drive circuit unit. The predetermined voltage or current supplied to the strip conductor immediately before the end of, or the predetermined voltage supplied to the strip conductor immediately before the end of the voltage or current supply scanning. A control signal derivation unit that obtains an end signal based on a voltage or current formed by delaying a voltage or current, and the predetermined voltage of the plurality of strip conductors when placed on the position detection plate. Alternatively, the detection means for generating a detection output signal according to the position of the current being applied, the detection output signal, the start signal and the end signal are supplied, and the end signal from the time of the start signal to the time of the end signal. Up to the effective detection period, and based on the detection output signal obtained in the effective detection period, an output signal forming circuit section for obtaining a position detection output representing the position of the detecting means on the position detection plate, Position detection device.