JP2010102627A - Position input device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a position input device for accurately inputting positions or coordinates of respective pressurizing points not only when pressing one point but also when completely simultaneously pressing two points. <P>SOLUTION: An operation part 1 includes a pressurizing operation surface configured such that a first conductor 11 for which a prescribed resistance value is uniformly distributed and a second conductor 12 of a resistance value set sufficiently small are conducted by local pressurization from the surface side. A drive part drives the operation part and includes an energizing aspect switching means for switching a first aspect and a second aspect. A signal processing part processes a current obtained from the first aspect and the second aspect by a current detection means 2 when the operation part is driven by the drive part by a current/position conversion means, a match/mismatch determination means and an input position output means, and detects a position specified by a pressurizing operation. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a position input device used as a touch panel, a tablet, or the like, and more particularly, to a position input device that specifies a pressing point position based on an operation signal obtained through a back-side conductor of a pressing operation surface.

  A position input device used as a touch panel, a tablet, or the like is conventionally known (see, for example, Patent Document 1).

  This position input device includes an operation unit having a pressing operation surface capable of designating a desired position by a pressing operation with a fingertip, a pen tip, etc., a drive unit for energizing and driving the operation unit, and an operation unit by the drive unit. In the driven state, an operation signal detection unit that detects an operation signal corresponding to a pressing operation in the operation unit, and an operation signal detected by the operation signal detection unit are processed to correspond to a position specified by the pressing operation. A signal processing unit for generating position data to be generated.

The operation unit is in the form of a film, a sheet, or a thin plate, and a predetermined electric resistance value is uniformly distributed, and a first electrode is also provided at one end in a predetermined displacement direction that serves as a position reference. The end includes a first conductor on which the second electrode is disposed, and a second conductor disposed on the back side of the first conductor so as to face each other with a slight gap. On the other hand, when the pressure is locally applied from the surface side, the first conductor and the second conductor are electrically connected in the pressure portion.
JP-A-8-190453

  In the above-described position detection device, the driving unit applies a predetermined voltage generated from the power source between the first electrode and the second electrode of the first conductor, and then on the first conductor. When any point is pressed and the first conductor and the second conductor are conducted, the resistance division voltage at the conduction point appears to the second conductor side. The operation signal detection unit includes voltage detection means for detecting the operation signal as a voltage value appearing on the second conductor.

  When two points on the first conductor are pressed at the same time and the two points are simultaneously connected to the second conductor, a potential difference between the two conduction points causes a second difference between the two conduction points. Current flows through the conductor. Then, the voltages at these two points are neutralized or averaged, and the voltage appearing on the second conductor becomes a value corresponding to the midpoint position between these two points, and is thus detected via the voltage detection means. It is not possible to directly generate the position data of the two corresponding pressing points from the voltage.

  Therefore, in order to enable a two-point press input, a complicated process for handling a two-point press must be incorporated in the signal processing unit. FIG. 6 shows an explanatory diagram of the two-point press handling process in the conventional apparatus.

  As shown in the figure, this two-point press corresponding process pays attention to the time difference of operation signals detected in succession, and when those time differences are within a minute time difference equivalent to simultaneous press, The coordinates obtained from the signal are recognized as the first point coordinates (P01), and the coordinates obtained from the subsequent operation signal are recognized as the middle point coordinates (P00), and the second point from these coordinates (P01, P00) is recognized. The coordinates (P02) are obtained by estimation. In the figure, reference numeral 1a denotes a pressing operation surface of the operation unit.

  However, in such a two-point press handling process, (1) since any one of the operation signals must be first, it is not possible to handle a complete simultaneous two-point press, and (2) the first point Since the coordinates of the second point are obtained from the coordinates and the coordinates of the middle point, the error of the second point coordinate is relatively large. (3) Two operation signals obtained with a slight time difference are 2 It is difficult to determine whether it is intended to be point-pressed or whether it has been quickly pressed once and then the middle-point position has been quickly re- pressed. (5) The calculation for specifying the position of the pressing point is complicated, and the software load on the signal processing unit is large. And so on.

  The present invention has been made by paying attention to the above-mentioned problems, and the object of the present invention is (1) not only in the case of one-point pressing but also in the case of two-point pressing at the same time, The position or coordinates of each pressing point can be accurately input. (2) Even if the pressing point slide operation such as widening or narrowing the interval between the pressing points is performed with two points pressed simultaneously The position or coordinates of the two pressing points can be input sequentially and continuously. (3) Whether the two operation signals obtained with a slight time difference are intended for two-point pressing, after one-point pressing The middle point position can be quickly re-determined and input can be made reliably. (4) The calculation for specifying the position of the pressing point is simple and the software load of the signal processing unit is reduced. It is to provide a light position input device.

  Other objects and effects of the present invention should be easily understood by those skilled in the art by referring to the contents of the following specification.

  [Problems to be solved by the invention] described above is considered to be solved by a position input device having the following configuration.

  That is, the position input device includes an operation unit, a drive unit, an operation signal detection unit, and a signal processing unit.

  The operation unit has a pressing operation surface on which a desired position can be designated by a pressing operation with a fingertip or a pen tip. The drive unit is for energizing and driving the operation unit. The operation signal detection unit detects an operation signal corresponding to a pressing operation on the operation unit in a state where the operation unit is driven by the drive unit. The signal processing unit processes the operation signal detected by the operation signal detection unit, and generates position data corresponding to the position designated by the pressing operation.

  The operation unit includes a first conductor and a second conductor. The first conductor has a film shape, a sheet shape, or a thin plate shape, and a predetermined electric resistance value is uniformly distributed, and a first electrode is provided at one end portion in a predetermined displacement direction serving as a position reference. A second electrode is disposed at the other end.

  The second conductor is disposed opposite to the back surface side of the first conductor with a slight gap, and the distributed electric resistance value is negligible compared to the electric resistance value distributed in the first conductor. It is set small enough to be possible.

  When the first conductor is locally pressurized from the surface side, the first conductor and the second conductor are electrically connected to each other at the pressure portion.

  The driving unit applies a predetermined voltage generated from a power source between the first electrode of the first conductor and the second conductor, and the second electrode of the first conductor Switch means for switching between a second energization mode applied between the first conductor and the second conductor.

  The operation signal detection unit includes a current detection unit that detects the operation signal as a current value flowing through the second conductor.

  The signal processing unit includes current / position / conversion means, coincidence / non-coincidence / determination means, and input position output means.

  The current / position / conversion means is obtained with reference to the first electrode side end for the current value detected in the first energized state among the current values output from the current detection means. Based on the known correlation between the current value and the position, the current value is converted to the first position, and the current value output in the second energized state is based on the second electrode side end. The current value is converted to the second position based on the known correlation between the current value to be performed and the position.

  The coincidence / non-coincidence / determination means collates the first position and the second position converted by the current / position / conversion means to determine whether or not they match.

  The input position output means outputs the first position data or the second position as a single input position when the coincidence / non-coincidence / determination means determines that both match, and the coincidence / mismatch / determination means When it is determined that the two do not match, the first position and the second position are output as two input positions, respectively.

  The position input device having such a configuration has the following operation.

  Any one of the two electrodes (first electrode, second electrode) forming a pair on the first conductor (for example, the first electrode), and the second conductor disposed on the back side of the second conductor; When the two-point pressing is performed in the state where the power supply voltage is applied during the first period (first energization mode), the distributed resistance value of the second conductor is almost negligible. The two conduction points are substantially short-circuited via the second conductor.

  Then, the current flowing through the closed circuit via the power supply depends only on the resistance value between the electrode on the power supply side (first electrode) and the conduction point closest to the first electrode (first electrode adjacent conduction point). It becomes the value. In other words, this resistance value corresponds to the distance from the first electrode to the first electrode adjacent pressing point (the position of the first electrode adjacent pressing point).

  Similarly, when the power supply voltage is applied between the second electrode and the second conductor on the first conductor (second energization mode), if two-point pressing is performed, the power supply voltage is closed via the power source. The current flowing through the circuit corresponds to the distance from the second electrode to the second electrode adjacent pressing point (the position of the second electrode adjacent pressing point).

  Therefore, the position of the first electrode adjacent pressing point and the position of the second electrode adjacent pressing point can be obtained by the current / position / conversion means.

  Here, as a matter of course, the position of the first electrode adjacent pressing point determined under the first energization mode and the position of the second electrode adjacent pressing point determined under the second energization mode Are substantially the same when pressed by one point, and different when pressed by two points.

  Therefore, if the position of the first electrode adjacent pressing point and the position of the second electrode adjacent pressing point are collated by the coincidence / non-coincidence / determination means and it is confirmed whether they coincide or not coincide, It is possible to easily determine whether or not the two-point pressing state is set.

  In the one-point pressing state, both the position of the first electrode adjacent pressing point and the position of the second electrode adjacent pressing point can be regarded as the position of a single pressing point, and in the two-point pressing state, The position of the first electrode adjacent pressing point and the position of the second electrode adjacent pressing point can be regarded as the position of the first electrode side pressing point and the position of the second electrode side pressing point constituting the two pressing points. .

  Therefore, the input position output means can output the position of a single pressing point when in the one-point pressing state, and accurately output the two positions constituting the two pressing points when in the two-point pressing state. it can.

  Since the 1st position input device has the above-mentioned operation, it has the following effects.

  That is, according to the first position input device, (1) the position or coordinates of each pressing point can be accurately input, not only in the case of one-point pressing, but also in the case of two-point pressing at the same time, (2) Even if the pressing point sliding operation such as increasing or decreasing the interval between the pressing points is performed while the two points are pressed simultaneously, the positions or coordinates of the two pressing points are successively and sequentially set. (3) Whether the two operation signals obtained with a slight time difference are intended to push two points or whether the middle point position is quickly pushed after one point push. It can be discriminated and input reliably, and (4) has a technical effect that the calculation for specifying the position of the pressing point is simple and the software load on the signal processing unit is light.

  In the position input device described above, the coincidence / mismatch / determination means determines that the two match when the deviation between the first position and the second position is within a predetermined reference deviation, If it is determined that they do not match when the deviation from the second position deviates from a predetermined reference deviation, an optimum determination is made according to the required position detection resolution by adjusting the reference deviation value. Processing can be realized.

  That is, when a unit region determined by position detection resolution is assumed, whether the first position and the second position described above coincide with each other or not coincides with each other. Result in the question of whether or not Accordingly, by making the above-described reference deviation value correspond to the size of the unit area determined by the position detection resolution, it is possible to determine the optimum match / mismatch.

  In the position input device described above, when the conduction point on the first conductor moves along the predetermined displacement direction, the distributed resistance value on the first conductor is changed to a predetermined first electrode or a second electrode. If the resistance value between the current and the conduction point is distributed so as to change linearly, a program for current / position / conversion can be simplified.

  In the above-described position input device, if the predetermined displacement direction is two linear orthogonal directions, and at least switch means is provided for each of the two displacement directions, an XY coordinate value can be input.

  In the above-described position input device, if both the first conductor and the second conductor are transparent, they are arranged on the front surface of the screen of the image display device to form a touch panel.

  According to the position input device of the present invention, (1) the position or coordinates of each pressing point can be accurately input even in the case of one-point pressing as well as in the case of two-point pressing at the same time. ) Even if two points are pressed at the same time, and a pressing point slide operation such as widening or narrowing the interval between the pressing points, the position or coordinates of these two pressing points are sequentially input continuously. (3) It is determined whether the two operation signals obtained with a slight time difference are intended to push two points or whether the middle point position is quickly pushed after one point is pushed. (4) The effect of having the technical effect that the calculation for specifying the position of the pressing point is simple and the software load of the signal processing unit is light. There is.

  Hereinafter, a preferred embodiment of a position input device according to the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a block diagram schematically showing the entire apparatus of the present invention with the structure of the operation unit as the center.

  The position input device includes an operation unit 1 having a pressing operation surface capable of designating a desired position by a pressing operation with a fingertip, a pen tip or the like, and a drive unit (details will be described later) for energizing and driving the operation unit 1. In the state where the operation unit is driven by the drive unit, an operation signal detection unit (details will be described later) for detecting an operation signal corresponding to the pressing operation in the operation unit, and an operation signal detected by the operation signal detection unit are processed. And a signal processing unit (details will be described later) for generating position data corresponding to the position designated by the pressing operation.

  The operation unit 1 has a film shape, a sheet shape, or a thin plate shape, and a predetermined electric resistance value is uniformly distributed, and a first electrode is also provided at one end portion in a predetermined displacement direction serving as a position reference. The other end is opposed to the first conductor 11 on which the second electrode is disposed, and the back surface side of the first conductor via a slight gap, and the distributed electrical resistance value is And the second conductor 12 set to be sufficiently small so as to be negligible as compared with the electric resistance value distributed on the conductor 11, and is locally applied to the first conductor 11 from the surface side thereof. When pressed, the first conductor 11 and the second conductor 12 are configured to conduct at the pressing portion.

  In the illustrated embodiment, the position input device according to the present invention is embodied as a transparent touch panel disposed on the front side of a display screen of an image display device (not shown).

  Therefore, as the first conductor 11, a film body having a rectangular shape made of a transparent film-like conductive material (for example, PET resin or the like) in which a predetermined electric resistance value is uniformly distributed (hereinafter referred to as “high resistance”). 11a) is adopted.

  A first electrode 111 in the X direction is disposed at one end portion in the X direction along the long side of the high resistance conductor film 11a, and a second electrode 112 in the X direction is disposed at the other end portion. These electrodes 111 and 112 are extended linearly along the corresponding short sides.

  A Y-direction first electrode 113 is disposed at one end portion in the Y direction along the short side of the high-resistance conductor film 11a, and a Y-direction second electrode 114 is disposed at the other end portion. These electrodes 113 and 114 are linearly extended along the corresponding long sides.

  As the second conductor 12, a film body having a similar rectangular shape made of a transparent film-like conductive material (for example, indium oxide or the like) having an electric resistance value of almost 0 (hereinafter referred to as “0 resistance conductor film”). 12a) is adopted.

  A first electrode 121 in the X direction is disposed at one end portion in the X direction along the long side of the zero-resistance conductive film 12a, and a second electrode 122 in the X direction is disposed at the other end portion. The electrodes 121 and 122 are linearly extended along the corresponding short sides.

  A Y-direction first electrode 123 is disposed at one end in the Y direction along the short side of the high-resistance conductor film 12a, and a Y-direction second electrode 124 is disposed at the other end. The electrodes 123 and 124 are linearly extended along the corresponding long sides.

  The high-resistance conductor film 11a and the zero-resistance conductor film 12a are stacked one above the other via spacer protrusions (not shown) that are uniformly distributed between the two. A slight gap is formed to prevent body conduction. When the high-resistance conductor film 11a is locally pressurized from the surface side, the high-resistance conductor film 11a and the zero-resistance conductor film 12a are electrically connected in the pressure portion.

  The drive unit applies a predetermined voltage generated from the power source E between the first electrode 111 in the X direction of the high-resistance conductor film 11a and the zero-resistance conductor film 12a, and a high resistance A second energization mode in the X direction applied between the second X-direction electrode 112 of the conductor film 11a and the zero-resistance conductor film 12a, and the first Y-direction electrode 113 and the zero-resistance conductor film of the high-resistance conductor film 11a A first energization mode in the Y direction applied between the second resistance direction film 12a and a second energization mode in the Y direction applied between the second Y direction electrode 114 of the high resistance conductive film 11a and the zero resistance conductive film 12a. Includes switch means for switching.

  In the illustrated example, the switch means includes a first switch S11 in the X direction, a second switch S12 in the X direction, a first switch S21 in the Y direction, a second switch S22 in the Y direction, The XY change-over switch S31 and the second XY change-over switch X32 are included.

The relationship between the first and second energization modes in the X direction and the Y direction and the state of each switch constituting the switch means is as follows. It is assumed that the positive potential of the power source E is + E (V) and the negative potential is 0 (V).
[First energization mode in X direction]
The first XY changeover switch S31 is set to the a side, the second XY changeover switch S32 is set to the a side, the X direction first switch S11 is turned OFF, and the X direction second switch S12 is turned ON.

  Then, the potential of the first electrode 111 in the X direction of the high-resistance conductor film 11a is + E (V), the potential of the second electrode 112 is 0 (V), and the potential of the second electrode 122 in the X direction of the zero-resistance conductor film 12a. The potential is 0 (V).

As a result, the power supply voltage E (V) is applied between the first electrode 111 in the X direction of the high resistance conductor film 11a and the second electrode 122 in the X direction of the zero resistance conductor film 12a.
[Second energization mode in X direction]
The first XY changeover switch S31 is set to the a side, the second XY changeover switch S32 is set to the a side, the first switch S11 in the X direction is turned on, and the second switch S12 in the X direction is turned off.

  Then, the potential of the first electrode 111 in the X direction of the high-resistance conductor film 11a is + E (V), the potential of the second electrode 112 is 0 (V), and the potential of the first electrode 121 in the X direction of the zero-resistance conductor film 12a. The potential is E (V).

As a result, the power supply voltage E (V) is applied between the second electrode 112 in the X direction of the high resistance conductive film 11a and the first electrode 121 in the X direction of the zero resistance conductive film 12a.
[First energization mode in Y direction]
The first XY selector switch S31 is on the b side, the second XY selector switch S32 is on the b side, the first switch S21 in the Y direction is OFF, and the second switch S22 in the Y direction is ON.

  Then, the potential of the first electrode 113 in the Y direction of the high-resistance conductor film 11a is + E (V), the potential of the second electrode 114 is 0 (V), and the potential of the second electrode 124 in the Y direction of the zero-resistance conductor film 12a. The potential is 0 (V).

As a result, the power supply voltage E (V) is applied between the first electrode 113 in the Y direction of the high resistance conductor film 11a and the second electrode 124 in the Y direction of the zero resistance conductor film 12a.
[Second energization mode in Y direction]
The first XY selector switch S31 is on the b side, the second XY selector switch S32 is on the b side, the first switch S21 in the Y direction is ON, and the second switch S22 in the Y direction is OFF.

  Then, the potential of the first electrode 113 in the Y direction of the high-resistance conductor film 11a is + E (V), the potential of the second electrode 114 is 0 (V), and the potential of the second electrode 124 in the Y direction of the zero-resistance conductor film 12a. The potential is 0 (V).

  As a result, the power supply voltage E (V) is applied between the second electrode 114 in the Y direction of the high resistance conductor film 11a and the first electrode 123 in the Y direction of the zero resistance conductor film 12a.

  The operation signal detection unit includes current detection means 2 that detects the operation signal as a current value flowing through a closed circuit via the zero-resistance conductive film 12. As will be described later, the current detection means 2 detects the value of the current flowing between the high-resistance conductor film 11a and the zero-resistance conductor film 12a through the pressing conduction point in each of the four conduction modes described above. So connected.

  The current value detected by the current detection means 2 can be read from the CPU 4 via the A / D converter 3.

  The CPU 4 is mainly composed of a microprocessor, a ROM, a RAM, and the like, and is detected by the above-described four energization mode switching processes and the current detection means 2 by operating according to the flowcharts of FIGS. 4 and 5. The signal processing for generating and outputting the coordinate data D (X, Y) of the pressing point from the current value is executed.

  Next, the principle of detecting the position of the pressing point in the position input device having the above configuration will be described.

  FIG. 2 shows a configuration diagram (in the case of one-point pressing) schematically showing the entire apparatus of the present invention with the equivalent circuit of the operation unit as the center. In addition, this figure demonstrates the position detection principle of the X direction regarding the press point P1.

  When the first switch S11 in the X direction is turned off, the second switch S12 is turned on, and the first energization mode is selected, the first electrode 111 of the high resistance conductive film 11a and the second of the zero resistance conductive film 12a A voltage E (V) of the power source E is applied between the electrodes 122.

  In this state, when the point P1 on the high-resistance conductor film 11a is pressed and the high-resistance conductor film 11a and the zero-resistance conductor film 12a conduct, the resistance R2 between the conduction point P1 and the second electrode 112 is Since it is short-circuited by the zero-resistance conductive film 12a, the current flowing through the current detection means 2 indicated by the wavy line in the figure reflects only the value of the resistance R1 between the first electrode 111 and the first electrode adjacent conduction point P1. Current (hereinafter referred to as “first resistance side current”) I1.

  The resistance value R1 also corresponds to the X-direction distance L1 between the first electrode 111 and the conduction point P1. Therefore, by applying the first resistance-side current I1 detected by the current detection means 2 to the relationship (known correlation) between the current I1 and the distance L1, the X-direction distance L1 with respect to the first electrode 111 is defined as: An X-direction position (hereinafter referred to as “first position”) with the first electrode at the pressing point P1 as a reference can be obtained.

  In this example, the relationship (known correlation) between the first resistance-side current I1 and the distance L1 is set to a linear relationship so that the distance L1 can be easily calculated. This can be easily realized by appropriately selecting the distributed resistance on the high resistance conductive film 11a, the shape of the first electrode 111, and the like.

  The first switch S11 in the X direction is ON (S11 ′ surrounded by a virtual line in the figure), the second switch S12 is OFF (S12 ′ surrounded by a virtual line in the figure), and the second energization mode is When selected, the voltage E (V) of the power source E is applied between the second electrode 112 of the high resistance conductor film 11a and the second electrode 122 of the zero resistance conductor film 12a.

  In this state, when the point P1 on the high-resistance conductor film 11a is pressed and the high-resistance conductor film 11a and the zero-resistance conductor film 12a conduct, the resistance R1 between the conduction point P1 and the first electrode 111 is Since it is short-circuited by the zero-resistance conductive film 12a, the current flowing through the current detection means 2 indicated by a solid line in the drawing is a current that reflects only the value of the resistance R2 between the first electrode 112 and the conduction point P1 (hereinafter, (Referred to as “second resistance side current”).

  The value of the resistance value R2 also corresponds to the X-direction distance L2 between the second electrode 112 and the conduction point P1. Therefore, by applying the current value I2 detected by the current detection means 2 to the relationship between the current value I2 and the distance L2 (known correlation), the X-direction distance L2 with respect to the second electrode 112 is set as the pressing point. The position in the X direction (hereinafter referred to as “second position”) with reference to the second electrode of P1 can be obtained.

  In this example, the relationship (known correlation) between the second resistance-side current I2 and the distance L2 is set to a linear relationship so that the distance L2 can be easily calculated. This can be easily realized by appropriately selecting the distributed resistance on the high resistance conductive film 11a, the shape of the second electrode 112, and the like.

  FIG. 3 shows a configuration diagram (in the case of two-point simultaneous pressing) schematically showing the entire apparatus of the present invention with the equivalent circuit of the operation unit as the center. This figure explains the principle of position detection in the X direction with respect to the two simultaneous pressing points P11 and P12.

  When the first switch S11 in the X direction is turned off, the second switch S12 is turned on, and the first energization mode is selected, the first electrode 111 of the high resistance conductive film 11a and the second of the zero resistance conductive film 12a A voltage E (V) of the power source E is applied between the electrodes 122.

  In this state, when the two points P11 and P12 on the high-resistance conductor film 11a are pressed and the high-resistance conductor film 11a and the zero-resistance conductor film 12a conduct at two points, the conduction point P11 and the second electrode 112 Is short-circuited by the zero-resistance conductor film 12a, the current flowing through the current detection means 2 indicated by the wavy line in the figure is only the value of the resistance R1 between the first electrode 111 and the conduction point P11. The reflected first resistance side current I1 is obtained.

  The resistance value R1 also corresponds to the X-direction distance L1 between the first electrode 111 and the conduction point P11. Therefore, by applying the first resistance-side current I1 detected by the current detection means 2 to the relationship (known correlation) between the current I1 and the distance L1, the X-direction distance L1 with respect to the first electrode 111 is defined as: The first position of the pressing point P11 can be obtained.

  The first switch S11 in the X direction is ON (S11 ′ surrounded by a virtual line in the figure), the second switch S12 is OFF (S12 ′ surrounded by a virtual line in the figure), and the second energization mode is When selected, the voltage E (V) of the power source E is applied between the second electrode 112 of the high resistance conductor film 11a and the second electrode 122 of the zero resistance conductor film 12a.

  In this state, when the two points P11 and P12 on the high-resistance conductor film 11a are pressed down and the high-resistance conductor film 11a and the zero-resistance conductor film 12a conduct at two points, the conduction point P12 and the first electrode 111 Is short-circuited by the 0-resistance conductor film 12a, the current flowing through the current detection means 2 indicated by the solid line in the figure is only the value of the resistance R2 between the second electrode 112 and the conduction point P12. The reflected second resistance side current I2 is obtained.

  The value of the resistance value R2 also corresponds to the X-direction distance L2 between the second electrode 112 and the conduction point P12. Therefore, by applying the second resistance side current I2 detected by the current detection means 2 to the relationship (known correlation) between the current value I2 and the distance L2, the X-direction distance L2 with respect to the second electrode 112 is obtained. The second position of the pressing point P12 can be obtained.

  Here, as is clear from the comparison between FIG. 2 and FIG. 3, the first position obtained under the first energization mode and the second position obtained under the second energization mode are as follows. In the case of the one-point press shown in FIG. 2, they are almost the same, and in the case of the two-point press shown in FIG.

  Therefore, if the first position and the second position are collated and it is confirmed whether or not they match, it is possible to easily determine whether the one-point pressing state or the two-point pressing state.

  In the one-point pressing state, both the first position and the second position can be regarded as the position of the single pressing point P1, and in the two-point pressing state, the first position and the second position are 2 It can be considered as the position of the 1st electrode side press point P11 which comprises a piece of press point, and the position P12 of the 2nd electrode side press point.

  Therefore, the position of a single pressing point can be output when the point is pressed, and the two positions constituting the two pressing points can be output accurately when the point is pressed.

  Next, based on the above-described position measurement principle, the operation of the position input device will be described in detail with reference to FIGS.

  FIG. 4 shows a flowchart schematically showing the entire control program executed by the CPU constituting the signal processing unit. As shown in the figure, in the CPU 4, after initializing various flags and registers in the initialization process (step 10), the X-axis side process (step 20) and the Y-axis side process (step 30). , And the coordinate data output process (step 40) are repeated in order.

  FIG. 5 is a flowchart showing details of the X-axis side processing in the flowchart of FIG. As shown in the figure, when the X-axis side processing is started, first, both the first and second changeover switches S31 and S32 are set to the a side and then set to the first energization mode. Therefore, the first switch S11 in the X direction is set to OFF, and the second switch S12 in the X direction is set to ON (step 2001).

  Subsequently, the first resistance side current I1 is read by reading the detection current of the current detection means 2 through the A / D converter 3 (step 2002).

  Subsequently, the first position corresponding to the read first resistance side current I1 is applied by fitting the value of the first resistance side current I1 read in the above to the known relationship between the current I1 and the first position. Is obtained (step 2003).

  This fitting may be performed by substituting the read current value I1 into a function expression indicating a known relationship between the current I1 and the first position, or reading a current value I1 from a function table indicating such a relationship. A table lookup method may be used in which is referred to as an argument. In any case, since the known relationship between the current I1 and the first position is linear, the target first position can be easily obtained.

  Subsequently, in order to set the second energization mode while maintaining both the first and second changeover switches S31 and S32 on the a side, the first switch S11 in the X direction is turned on and the second switch in the X direction is turned on. Each of the switches S12 is set to OFF (step 2004).

  Subsequently, the second resistance side current I2 is read by reading the detection current of the current detection means 2 via the A / D converter 3 (step 2005).

  Subsequently, by applying the value of the second resistance side current I2 read above to the known relationship between the current I2 and the second position, the second position corresponding to the read second resistance side current I2 is obtained. Is obtained (step 2006).

  This fitting may be performed by substituting the read current value I2 into a function equation indicating a known relationship between the current I1 and the first position, or reading a current value I2 from a function table indicating such a relationship. A table lookup method may be used in which is referred to as an argument. In any case, since the known relationship between the current I2 and the second position is linear, the target first position can be easily obtained.

  Subsequently, it is determined whether or not the first position and the second position obtained above match (step 2007). In this coincidence / non-coincidence / determination, when the deviation (| first position−second position |) between the first position and the second position is within a predetermined reference deviation a, it is determined that the two coincide with each other. When the deviation between the position 1 and the second position deviates from a predetermined reference deviation, it is determined that the two do not match. At this time, by adjusting the value of the reference deviation, an optimum determination process can be realized according to the required position detection resolution.

  That is, assuming a unit region determined by the position detection resolution, whether the first position and the second position match or does not match depends on whether or not the two positions are within the same unit region. This results in a problem. Accordingly, by making the above-described reference deviation value correspond to the size of the unit area determined by the position detection resolution, it is possible to determine the optimum match / mismatch.

  As is clear from the above explanation of the principle, the fact that they match each other means that the point is one-point press, and that both do not match means that the point is two-point press. Here, as for the value of the reference deviation a, if it is large, the accuracy of determining whether to press one point or two points increases, but the input position resolution decreases. On the other hand, if it is small, the accuracy of determining whether to press one point or two points decreases, but the input position resolution increases. Therefore, by adjusting the value of the reference deviation a, it is possible to obtain the target one-point press / two-point press / determination accuracy and the input position resolution.

  Subsequently, when it is determined that they match (step 2007 YES), the first position or the second position is temporarily stored as a single input position P1 (step 2008), and when it is determined that they do not match (step 2008) 2007NO), the first position and the second position are stored as two input positions P11 and P12, respectively (step 2010).

  Subsequently, these stored values are collated with each previous stored value (step 2009 or step 2011), and the collation is performed a predetermined number of times n which becomes an error elimination criterion due to noise or the like in either one point push or two point push. If a match is confirmed (YES in step 2012), the X-axis side processing ends, and the process proceeds to Y-axis side processing (step 30). Note that the switching cycle between the first energization mode and the second energization mode may be appropriately determined in consideration of the intended input responsiveness. In this embodiment, the switching cycle is 150 times / second.

  The details of the Y-axis side processing (step 30) are not shown, but are the same as the details of the X-axis side processing shown in FIG. 5 except that the X-axis side is changed to the Y-axis side.

  When the Y-axis side processing (step 30) is completed, the single input position P1 or two input positions simultaneously pressed are output as the input coordinate data D (X, Y). The coordinate data D (X, Y) output in this way is taken into an input target device (for example, an input device for a work device, a personal computer, a game machine, etc.) and is subjected to a predetermined calculation process.

  According to the above embodiment, there are the following effects.

  According to this position input device, (1) the position or coordinates of each pressing point can be accurately input even in the case of one-point pressing as well as in the case of two-point pressing at the same time. Even if the pressing point slide operation such as widening or narrowing the interval between the pressing points with the simultaneous pressing of the points is performed, the positions or coordinates of the two pressing points can be sequentially input continuously. (3) It is possible to determine whether the two operation signals obtained with a slight time difference are intended to push two points or whether the middle point position is quickly pushed again after pushing one point. (4) Easy calculation for specifying the position of the pressing point, reducing the software burden on the signal processing unit, (5) Providing a touch panel that allows XY coordinate input What can be done, (5) Accuracy of 1-point press or 2-point press, and input It can be appropriately set the coordinate resolution, the technical effect of said obtained.

  In the above-described embodiment, some of the components of the position input device can be modified as follows.

  The drive unit is not limited to the circuit configuration shown in the drawing. In short, a predetermined voltage generated from the power source is applied between the first electrode 111 of the high-resistance conductor film 11a and the zero-resistance conductor film 12a. As long as it includes switch means for switching between the first energization mode and the second energization mode applied between the second electrode 112 of the high-resistance conductor film 11a and the 0-resistance conductor film 12a. Good.

  Therefore, for example, the positive side of the power source E is selectively switched to the first point electrode or the second electrode in the X direction of the high resistance conductive film 11 via the changeover switch, while the negative side of the power source E is A similar purpose can be achieved even in a configuration in which the electrode is fixedly connected to any electrode of the zero-resistance conductor film 12.

  Further, instead of the DC power supply E, an AC power supply may be employed. In that case, an alternating current type must be adopted as the current detection means 2.

  As another embodiment other than the touch panel of the position input device according to the present invention, the following may be considered.

  That is, the position input device according to the present invention can be embodied as a tablet used for handwritten input to a personal computer or the like.

  In that case, the first and second conductors 11 and 12 do not need to be transparent. In addition, the first conductor needs to be in the form of a film, a sheet, or a thin plate, but the second conductor 12 may be a material having a resistance value distribution close to 0, and is not necessarily in the form of a film. It is not necessary to have a sheet shape or a thin plate shape.

  The present invention improves usability because a two-point press input can be performed simultaneously on a transparent touch panel arranged on the front of the screen of the image display or a tablet for pen-inputting a handwritten figure to a personal computer.

It is a block diagram which shows typically the whole this invention apparatus centering on the structure of an operation part. It is a block diagram (in the case of one point push) which shows typically the whole apparatus of this invention centering on the equivalent circuit of an operation part. It is a block diagram (in the case of two-point simultaneous pushing) which shows typically the whole device of the present invention centering on the equivalent circuit of an operation part. It is a flowchart which shows roughly the whole control program performed with CPU which comprises a signal processing part. 5 is a flowchart showing details of X-axis side processing in the flowchart of FIG. 4. It is explanatory drawing which shows an example of the 2 point press corresponding | compatible process in a conventional apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Operation part 1a Press operation surface 2 Current detection means 3 A / D converter 4 CPU
DESCRIPTION OF SYMBOLS 11 1st conductor 12 2nd conductor 11a High resistance conductor film 12a 0 resistance conductor film 111 1st electrode (high resistance conductor film) of X direction
112 X-direction second electrode (high resistance conductor film)
113 Y direction first electrode (high resistance conductor film)
114 Second electrode in Y direction (high resistance conductive film)
121 X direction first electrode (0 resistance conductor film)
122 X direction second electrode (0 resistance conductor film)
123 1st electrode in Y direction (0 resistance conductor film)
124 Y-direction second electrode (0-resistance conductor film)
P1 Pressing point when one point is pressed P11 First pressing point when pressing two points P12 Second pressing point when pressing two points S11 First switch in X direction (first switching state)
S11 ′ X direction first switch (second switching state)
S12 X direction second switch (first switching state)
S12 'X direction second switch (second switching state)
S21 First switch in Y direction S22 Second switch in Y direction S31 First XY changeover switch S32 Second XY changeover switch E Power supply R1 First electrode adjacent resistance value R2 Second electrode adjacent resistance value L1 First electrode to first Distance from 1 electrode adjacent pressing point L2 Distance from 2nd electrode to 2nd electrode adjacent pressing point

Claims (5)

An operation unit having a pressing operation surface capable of designating a desired position by a pressing operation with a fingertip or a pen tip, a driving unit for energizing and driving the operating unit, and a state in which the operating unit is driven by the driving unit An operation signal detection unit that detects an operation signal corresponding to the pressing operation in the operation unit, and processing the operation signal detected by the operation signal detection unit, and position data corresponding to a position specified by the pressing operation A signal processing unit for generating
The operation unit is
It is in the form of a film, a sheet, or a thin plate, and a predetermined electrical resistance value is uniformly distributed, and a first electrode is provided at one end in a predetermined displacement direction that serves as a position reference, and a second electrode is provided at the other end. A first conductor having a second electrode disposed thereon;
The first conductor is oppositely disposed on the back side of the first conductor with a slight gap, and the distributed electric resistance value is sufficiently negligible compared to the electric resistance value distributed on the first conductor. And a second conductor set to be small,
When the first conductor is locally pressed from the surface side, the first conductor and the second conductor are configured to be electrically connected to each other at the pressing portion.
The drive unit is
A first energization mode in which a predetermined voltage generated from a power supply is applied between the first electrode of the first conductor and the second conductor; the second electrode of the first conductor; Including switch means for switching between a second energization mode applied between the second conductor and the second conductor;
The operation signal detector is
Current detection means for detecting the operation signal as a current value flowing through the second conductor;
The signal processing unit
Among the current values output from the current detection means, the current value detected in the first energization state is a known current value and position obtained with reference to the first electrode side end. Based on the correlation, the current value is converted to the first position, and the current value output in the second energization state is calculated by comparing the current value and the position with reference to the second electrode side end. Current / position converting means for converting the current value to the second position based on the known correlation;
A match / mismatch / determination means for comparing the first position and the second position converted by the current / position / conversion means to determine whether or not they match,
When the match / mismatch / determination means determines that both match, the first position or the second position is output as a single input position, and the match / mismatch / determination means A position input device comprising: input position output means for outputting the first position and the second position as two input positions when it is determined that they do not match.   The coincidence / non-coincidence / determination means determines that the first position and the second position match when the deviation between the first position and the second position is within a predetermined reference deviation. 2. The position input device according to claim 1, wherein when the deviation of the distance deviates from a predetermined reference deviation, it is determined that the two do not coincide with each other.   The distributed resistance value on the first conductor is such that when the conduction point on the first conductor moves along the predetermined displacement direction, the conduction point with the predetermined first electrode or the second electrode. 2. The position input device according to claim 1, wherein the resistance values are distributed so as to change linearly.   2. The position input device according to claim 1, wherein the predetermined displacement directions are two orthogonal orthogonal directions, and at least the energization mode switching means is provided for each of the two displacement directions. .   The position input device according to claim 1, wherein each of the first conductor and the second conductor is transparent.

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