JP2014099204A - Position detection device and position detection method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a position detection device and a position detection method, capable of preventing a pointer from erroneously detecting a position.SOLUTION: A position detection device 100 comprises: a transmission conductor group 12 consisting of a plurality of conductors arranged in a first direction; a reception conductor group 14 consisting of a plurality of conductors arranged in a second direction intersecting the first direction; a signal detection circuit 34, etc., for detecting a signal generated in the reception conductor group 14 on the basis of position indication by the pointer; a transmission conductor selection circuit 23 for supplying a spectrum diffusion code to the transmission conductor group 12; and a reception conductor selection circuit 31. The transmission conductor group 12 and the reception conductor group 14, respectively, are divided into at least a fist conductor group and a second conductor group adjacent to each other, and a conductor is selected so that a direction selecting each conductor forming a first conductor group and a direction selecting each conductor forming a second conductor group are different from each other.

Description

  The present invention relates to a position detection apparatus and method for detecting the position of an indicator by an electrostatic capacity method.

  Conventionally, a plurality of X-axis electrodes arranged in the X-axis direction and a plurality of Y-axis electrodes arranged in the Y-axis direction are arranged to cross each other, and a voltage having a predetermined frequency is applied by sequentially switching the X-axis electrodes, There is known a position detection device that sequentially switches Y-axis electrodes and processes signals appearing on the respective Y-axis electrodes (see, for example, Patent Document 1). When an indicator such as a human finger approaches the position (cross point) where the X-axis electrode and the Y-axis electrode intersect, the capacitance between the X-axis electrode and the Y-axis electrode changes, and this Y-axis electrode Since the signal appearing on the display changes, the Y-axis electrode is switched in order (scanning the Y-axis electrode) and the state of the change in the signal appearing on each Y-axis electrode is observed. You can know the position.

JP 2009-192306 A (page 1-12, FIG. 1-9) JP 07-319612 A Japanese Patent Application Laid-Open No. 07-104911

  In the position detection device disclosed in Patent Document 1, since the Y-axis electrodes on the signal detection side are sequentially switched, when the range (area) to be position-detected increases and the number of Y-axis electrodes increases, One scan time, that is, time is required for position detection. Regarding the point that it takes time to detect the position, it is conceivable to reduce the scanning time by dividing the scanning area into a plurality of parts and simultaneously scanning each of the divided areas.

  FIG. 15 is a diagram showing a schematic operation in the case where the scanning area is divided into a plurality of parts and scanning is performed for each of the divided areas at the same time. In the example shown in FIG. 15, it is assumed that the entire scanning area is divided into N, and each divided area is indicated by blocks 1, 2,. A vertical line included in each block indicates an electrode (Y-axis electrode or X-axis electrode), and an arrow disposed above each block indicates a scanning order. Thus, by performing scanning in each block in parallel, the scanning time of the entire scanning region can be reduced to 1 / N, and the speed of position detection can be increased.

FIG. 16 is a diagram illustrating a specific example of the changeover switches S _{1 to} S _N used when the X-axis electrode is divided into N parts. As shown in FIG. 16, the X-axis electrodes are sequentially selected in the same direction (from bottom to top) in each of the changeover switches S _{1 to} S _N.

FIG. 17 is a diagram illustrating a specific example of the changeover switches T _{1 to} T _N used when the Y-axis electrode is divided into N parts. As shown in FIG. 17, the Y-axis electrodes are sequentially selected in the same direction (from left to right) in each of the changeover switches T _{1 to} T _N.

  By the way, when the scanning area is divided into a plurality of parts and scanning is performed in parallel for each of the divided areas, when the indicator moves at a high speed, the detection range that should be detected as a continuous area becomes discontinuous. As a result, there is a problem that there is a risk of erroneous detection as if different indicators were detected.

  FIG. 18 is an explanatory diagram of a detection range. FIG. 18A shows the correspondence between the scanning area and the position of the fingertip (indicator) of the human body. FIG. 18B shows the detection result of the fingertip. In FIG. 18, A, B, and C are examples in the case where the fingertip position does not overlap the block boundary, and D and E are examples in which the fingertip position overlaps the block boundary (shown by a one-dot chain line). It is shown. It is assumed that the electrodes are selected in the order from left to right.

  When the position of the fingertip does not overlap the block boundary and the position of the fingertip is stationary, as shown by A, a substantially circular area is obtained as the detection range. When the position of the fingertip is moving upward, as shown in B, an elliptical area in which the major axis is arranged in the upper right diagonal direction is obtained as the detection range. On the other hand, when the position of the fingertip is moving downward, as shown in C, an elliptical area in which the major axis is arranged in the diagonally lower right direction is obtained as the detection range.

  On the other hand, when the position of the fingertip overlaps the boundary of the block, for example, when the position of the fingertip is moving upward, as shown in D, an ellipse having a long axis arranged in the upper right diagonal direction A shape region is obtained as a detection range divided by block boundaries. In this case, when the moving speed of the fingertip increases, as shown by E, the two divided elliptical regions are completely separated.

This is a phenomenon caused by performing simultaneous detection for a plurality of blocks. When detecting adjacent conductors in different blocks, a difference in scanning time for one block occurs as a delay in detection results. For example, in FIG. 17, when focusing on the block to which the conductor X ₇ and the conductor X ₈ belong, the conductors X ₀ , X ₈ ,... Are first selected and signals are detected. Next, the conductors X ₁ , X ₉ ,... Are selected and a signal is detected. There are seven switchings until conductor X ₇ is selected. Therefore, for the conductor X ₇ and the conductor X ₈ , a selection / detection difference of 7 times appears in the detection time. Therefore, when the fingertip moves so as to straddle adjacent blocks, a phenomenon that the detection results are separated occurs.

  Therefore, when the position of the indicator is determined based on the detection result obtained corresponding to one scanning time, two completely separated areas are erroneously detected as corresponding to different indicators. Become.

  The present invention has been created in view of such a point, and an object of the present invention is to provide a position detection apparatus and method that can prevent erroneous detection of the position of a pointer.

  In order to solve the above-described problem, a position detection device of the present invention is arranged in a first conductor pattern composed of a plurality of conductors arranged in a first direction, and in a second direction intersecting the first direction. A second conductor pattern composed of a plurality of conductors, a signal transmission unit connected to the first conductor pattern and supplying a spread spectrum code to the first conductor pattern, and a position indication by an indicator, And a signal detection unit that detects a signal generated in the second conductor pattern, wherein the plurality of conductors constituting the second conductor pattern are connected to at least the first conductor group and the first conductor group adjacent to each other. Divided into two conductor groups, and a plurality of conductors are selected such that the direction of selecting each conductor constituting the first conductor group is different from the direction of selecting each conductor constituting the second conductor group. Together with the first conductor group And a conductor selecting section for selecting a plurality of conductors as the switching timing of the arrangement conductors on the side adjacent the second conductor group matches.

  When a plurality of conductors constituting a conductor pattern are divided into a first conductor group and a second conductor group, a conductor is selected for each conductor group and the selected conductor is switched in a predetermined direction, two adjacent conductors Since the direction of switching the conductors in each conductor group is different from each other, the conductor selection timing in the vicinity of the boundary between these two conductor groups can be matched, and even if the indicator moves, this indicator The region detected in response to is not divided due to a shift in the timing of switching the conductor, and it is possible to prevent erroneous detection of the position of the indicator.

  Further, when the second conductor pattern on the signal detection side is divided, it is possible to reduce a time lag for detecting signals of conductors arranged in the vicinity of the boundary between adjacent conductor groups, and to switch conductors. It is possible to prevent erroneous detection of the position of the indicator that occurs due to a shift in timing.

  In addition, the first conductor pattern is divided into the first conductor group and the second conductor group, and the signal transmission unit has a different spectrum spread for each of the first conductor group and the second conductor group. It is desirable to supply the code in parallel. When the first conductor pattern on the side where the spread spectrum code is supplied is divided, the time lag for supplying the spread spectrum code to the conductors arranged in the vicinity of the boundary between adjacent conductor groups can be reduced. It is possible to prevent erroneous detection of the position of the indicator, which occurs due to a shift in the timing of switching the.

  Further, the above-described division of the plurality of first conductor patterns and the division of the plurality of second conductor patterns may be performed simultaneously. Even in this case, it is possible to prevent erroneous detection of the position of the indicator, which is caused by a shift in the timing of switching the conductor.

  In addition, the above-described conductor selection unit makes one round of selection of each conductor in the direction of selecting each conductor constituting the first conductor group and the direction of selecting each conductor constituting the second conductor group. It is desirable to reverse the order of selection each time. When the order of selection is reversed, distortion of the detection range when the indicator moves can be alleviated by averaging the signals obtained by repeating the selection operation for one round several times. Further, erroneous detection can be prevented.

  In addition, it is preferable that the conductor selection unit described above selects a conductor in at least one of the first conductor group and the second conductor group for a plurality of adjacent conductors. As a result, the level of the signal detected by the signal detector can be increased, and the detection accuracy can be improved by improving the reception sensitivity of the signal.

It is a figure showing the whole position detector of one embodiment. It is sectional drawing of a sensor part. It is a figure which shows the detailed structure of a multifrequency signal supply circuit. It is a figure which shows the detailed structure of a transmission conductor selection circuit. It is a figure which shows the detailed structure of a receiving conductor selection circuit and an amplifier circuit. It is explanatory drawing of the signal level detected by a signal detection circuit. It is a figure which shows the switching order in each of the changeover switch provided in the transmission conductor group side. It is a figure which shows the switching order in each of the changeover switch provided in the receiving conductor group side. It is a figure which shows the detection result when the fingertip set | placed on the sensor part so that the boundary of two blocks may be moved to the upper direction at high speed. It is a figure which shows the switching timing of a transmission conductor. It is a figure which shows the switching timing of a receiving conductor. It is a figure which shows the specific switching order at the time of inverting the switching order of the conductor by the side of a transmission conductor group for every flame | frame. It is a figure which shows the specific switching order at the time of reversing the switching order of the conductor by the side of a receiving conductor group for every flame | frame. It is a figure which shows the specific switching order in the case of selecting two receiving conductors simultaneously. It is a figure which shows schematic operation | movement in the case of dividing | segmenting a scanning area | region into multiple and scanning simultaneously about each division area. It is a figure which shows the specific example of the changeover switch used when an X-axis electrode is divided into N. It is a figure which shows the specific example of the selector switch used when a Y-axis electrode is divided into N. It is explanatory drawing of a detection range.

  Hereinafter, a position detection device according to an embodiment to which the present invention is applied will be described with reference to the drawings.

(First embodiment)
FIG. 1 is a diagram illustrating an overall configuration of the position detection apparatus according to the first embodiment. As shown in FIG. 1, the position detection device 100 of the present embodiment is for detecting the position of an indicator constituted by a human finger or the like, and includes a sensor unit 10, a transmission unit 20, a reception unit 30, A control circuit 40 is provided. The "indicator" is provided with a conductor at the tip, and transmits signals from the pen that is detected by sucking up an electrostatic field using the same principle as finger detection in a path connected to the ground through the human body, or from the pen itself. A pen is also included.

  The sensor unit 10 includes a transmission conductor group 12 (first conductor pattern) including a plurality of transmission conductors 11 arranged at equal intervals in a predetermined direction (first direction), and is orthogonal to the arrangement direction of the plurality of transmission conductors 11. A conductor pattern composed of a reception conductor group 14 (first conductor pattern) composed of a plurality of reception conductors 13 arranged at equal intervals in a direction (second direction).

  FIG. 2 is a cross-sectional view of the sensor unit 10 and shows a partial cross-section along one transmission conductor 11. As shown in FIG. 2, the first glass substrate 15, the transmission conductor 11, the spacer 16, the reception conductor 13, and the second glass substrate 17 are laminated in this order, and the indicator approaches the surface of the second glass substrate 17. Sometimes the position is detected.

The transmission conductor 11 and the reception conductor 13 have a flat plate shape, and are formed using, for example, a transparent electrode film made of an ITO (Indium Tin Oxide) film or a copper foil. In the present embodiment, 64 transmission conductors 11 are arranged in the vertical direction (Y direction) at a predetermined interval (for example, an interval of 3.2 mm). In addition, 128 reception conductors 13 are arranged in a horizontal direction (X direction) at a predetermined interval (for example, an interval of 3.2 mm). In FIG. 1, Y _{0 to} Y ₆₃ correspond to 64 transmission conductors 11, and the transmission conductors 11 are arranged in the order of Y _{0 to} Y ₆₃ . X _{0 to} X ₁₂₇ correspond to each of 128 reception conductors 13, and the reception conductors 13 are arranged in the order of X _{0 to} X ₁₂₇ .

  The spacer 16 is an insulator, and is formed using, for example, PVB (Poly Vinyl Butyral), EVA (Ethylene Vinyl Acetate), silicon rubber, or the like. Instead, the first and second glass substrates 15 and 17 may use a sheet-like (film-like) base material made of synthetic resin or the like.

The transmission unit 20 shown in FIG. 1 includes a clock generation circuit 21, a multi-frequency signal supply circuit 22, and a transmission conductor selection circuit 23. The clock generation circuit 21 generates a reference signal having a predetermined frequency. The multi-frequency signal supply circuit 22 generates signals of 16 types of frequencies f ₀ , f ₁ ,..., F ₁₅ using the reference signal output from the clock generation circuit 21, and these signals are parallelly generated. Output.

FIG. 3 is a diagram showing a detailed configuration of the multi-frequency signal supply circuit 22. Multi-frequency signal supply circuit 22, 16 types of frequency f _0, f _1, · · ·, 16 pieces of signal generator 22-0 and 22-1 for generating separately a signal f _15, · · ·, 22 -15. Each of the signal generators 22-0 to 22-15 generates signals having frequencies f _{0 to} f ₁₅ based on the reference signal output from the clock generator circuit 21. For example, each of the signal generation units 22-0 to 22-15 generates a signal having a predetermined frequency by dividing or multiplying the reference signal output from the clock generation circuit 21. Alternatively, each of the signal generators 22-0 to 22-15 has a waveform data ROM that holds sine wave waveform data having different periods, and is synchronized with the reference signal output from the clock generation circuit 21. by reading the waveform data to generate a sine wave signal of frequency f ₀ ~f _15.

  The transmission conductor selection circuit 23 selects the transmission conductor 11 that is a supply destination of 16 signals output in parallel from the multi-frequency signal supply circuit 22, and sequentially switches the transmission conductor 11 that is the selection destination.

FIG. 4 is a diagram showing a detailed configuration of the transmission conductor selection circuit 23. The transmission conductor selection circuit 23, 16 types of frequency f _0, f _1, ..., 16 pieces of the changeover switch 23-0,23-1 the signal f ₁₅ is input separately, ..., 23- 15 is provided. In the present embodiment, the 64 transmission conductors 11 are divided into 16 blocks B0 to B15 and grouped (divided). One of the two adjacent blocks corresponds to the first conductor group, and the other corresponds to the second conductor group.

The blocks B0 includes four transmission conductors 11 which are adjacent to each other represented by Y ₀ to Y _3. The changeover switch 23-0 connects the transmission conductor 11 to which the signal of the frequency f ₀ output from the signal generation unit 22-0 is supplied at a predetermined time interval in the order of Y ₃ , Y ₂ , Y ₁ , Y _0. Switch repeatedly with. In FIG. 4, the switching direction of the transmission conductor 11 is indicated by arrows illustrated in the changeover switches 23-0 to 23-15.

The block B1 includes _four transmission conductors 11 that are arranged adjacent to each other, indicated by Y ₄ to Y ₇ . The changeover switch 23-1 transmits the transmission conductor 11 that is the supply destination of the signal of the frequency f ₁ output from the signal generator 22-1 at a predetermined time interval in the order of Y ₄ , Y ₅ , Y ₆ , Y _7. Switch repeatedly with.

  The same applies to the other blocks B2 to B15 and the changeover switches 23-2 to 23-15, and each of the changeover switches 23-2 to 23-15 is output from the corresponding signal generation units 22-2 to 22-15. The transmission conductor 11 which is a signal supply destination is repeatedly switched at a predetermined order and time interval. Details of the switching order of the transmission conductors 11 in the changeover switches 23-0 to 23-15 will be described later.

  The receiving unit 30 shown in FIG. 1 includes a reception conductor selection circuit 31, an amplification circuit 32, an analog-digital conversion circuit (A / D) 33, a signal detection circuit 34, and a position calculation circuit 35.

  FIG. 5 is a diagram showing a detailed configuration of the reception conductor selection circuit 31 and the amplification circuit 32. The reception conductor selection circuit 31 includes 16 change-over switches 31-0, 31-1,..., 31-15 that sequentially switch the corresponding eight reception conductors 13. In the present embodiment, the 128 reception conductors 13 are divided into 16 blocks D0 to D15 and grouped (divided). One of the two adjacent blocks corresponds to the first conductor group, and the other corresponds to the second conductor group.

Block D0 includes eight reception conductors 13 which are adjacent to each other represented by X ₀ to X _7. The change-over switch 31-0 selects one of these eight receiving conductors 13 and in the order of X ₀ , X ₁ , X ₂ , X ₃ , X ₄ , X ₅ , X ₆ , X ₇ . This selection state is switched repeatedly at predetermined time intervals. In FIG. 5, the switching direction of the reception conductor 13 is indicated by the arrows illustrated in the changeover switches 31-0 to 31-15.

Block D1 includes eight reception conductors 13 which are adjacent to each other represented by X ₈ to X _15. Selector switch 31-1 is configured to select one from among these eight reception conductors 13, in the order of _{X 15, X 14, X 13} , X 12, X 11, X 10, X 9, X 8 This selection state is switched repeatedly at predetermined time intervals.

  The same applies to the other blocks D2 to D15 and the changeover switches 31-2 to 31-15, and each of the changeover switches 31-2 to 31-15 is arranged adjacent to each other in the corresponding blocks D2 to D15. While selecting one out of the two receiving conductors 13, the selection state is switched repeatedly in a predetermined order and time interval. Details of the switching order of the reception conductors 13 in the changeover switches 31-0 to 31-15 will be described later.

  The amplifier circuit 32 includes 16 current-voltage conversion circuits (I / V) 32-0, 32-1,..., 32-15 and a changeover switch 32A. Each of the current-voltage conversion circuits 32-0 to 32-15 has a one-to-one correspondence with each of the changeover switches 31-0 to 31-15. Each of the current-voltage conversion circuits 32-0 to 32-15 amplifies the current I output from the reception conductor 13 selected by the corresponding changeover switch 31-0 or the like with a predetermined gain and converts it to a voltage V. . The changeover switch 32 </ b> A sequentially selects signals (voltages) output from the 16 current-voltage conversion circuits 32-0 to 32-15 and inputs them to the analog-digital conversion circuit 33.

  The analog-digital converter 33 converts the output voltages of the 16 current-voltage conversion circuits 32-0 to 32-15, which are sequentially selected by the changeover switch 32A, into data having a predetermined number of bits.

Based on the data output from the analog-to-digital converter 33, the signal detection circuit 38 has each of 16 types of frequencies f ₀ , f ₁ ,..., F ₁₅ output from the multi-frequency signal supply circuit 22. The signal level of is detected.

FIG. 6 is an explanatory diagram of signal levels detected by the signal detection circuit 38. FIG. 6A shows a state where the finger of the human body as the indicator is not approaching the cross point (intersection position) between the transmission conductor 11 and the reception conductor 13. FIG. 6B shows a state in which a finger approaches the cross point. As shown in FIG. 6A, when the finger is not approaching the cross point, the transmission conductor 11 and the reception conductor 13 are capacitively coupled via the spacer 16 at the cross point. The emitted electric field converges toward the receiving conductor 13. Therefore, when a signal having a predetermined frequency (any one of f _{0 to} f ₁₅ ) is supplied to the transmission conductor 11, a current corresponding to the degree of capacitive coupling can be extracted from the reception conductor 13 capacitively coupled to the transmission conductor 11. . On the other hand, as shown in FIG. 6B, when the finger is close to the cross point, the current can be taken out from the receiving conductor 13 as in the case where the finger is not approaching. The degree of capacitive coupling between the conductor 11 and the receiving conductor 13 is different. That is, a part of the electric field emitted from the transmission conductor 11 converges toward the finger, so the degree of capacitive coupling with the reception conductor 13 is weakened, and the current extracted from the reception conductor 13 is reduced.

In this embodiment, 16 types of signals of frequencies f ₀ , f ₁ ,..., F ₁₅ are supplied in parallel to each of the 16 transmission conductors 11 intersecting with one reception conductor 13. Therefore, the data corresponding to the reception conductor 13 includes these 16 types of frequency components. The signal detection circuit 34 extracts these 16 types of frequency components separately (for example, extracts by performing synchronous detection), and detects a signal level corresponding to each frequency component.

The signal level detected by the signal detection circuit 34 is stored in correspondence with the position of the cross point. For example, a combination of Y ₀ to Y ₆₃ specifying the transmission conductor 11 and X _{0 to} X ₁₂₇ specifying the reception conductor 13 is an address indicating the position of the cross point, and the address and the signal level corresponding to the cross point are The combination is stored. When 16 types of frequency components included in a signal output from one receiving conductor 13 are considered, a signal is transmitted to any transmission conductor 11 in each of the blocks B0 to B15 of the transmission conductor group 12 at that time. Since it is known whether the signal is supplied, the transmission conductor 11 that is the signal supply destination can be specified for each frequency.

  The position calculation circuit 35 includes a switching operation by the changeover switches 23-0 to 23-15 in the transmission conductor selection circuit 23 and a switching operation by the changeover switches 31-0 to 31-15 in the reception conductor selection circuit 31. The detection operation of the signal level corresponding to all the cross points at which the timing of one round, that is, all the transmission conductors 11 of the transmission conductor group 12 of the sensor unit 10 and all the reception conductors 14 of the reception conductor group 13 intersect is completed. At the timing, the cross point where the signal level is reduced is calculated as the position where the finger is approaching.

  The transmission conductor selection circuit 23 and the reception conductor selection circuit 31 described above correspond to the conductor selection unit, and the amplification circuit 32, the analog-digital conversion circuit 33, and the signal detection circuit 34 correspond to the signal detection unit. The clock generation circuit 21 and the multifrequency signal supply circuit 22 correspond to a signal transmission unit and a multifrequency signal supply unit.

  Next, the switching order of the transmission conductors 11 in the changeover switches 23-0 to 23-15 and the switching order of the reception conductors 13 in the changeover switches 31-0 to 31-15 will be described. In this embodiment, in each of the blocks B0-0 to B0-15 of the transmission conductor group 12, the switching order of the transmission conductors 11 is set so as to be opposite to each other with respect to adjacent blocks. In addition, in each of the blocks D0-0 to D0-15 of the reception conductor group 14, the switching order of the reception conductors 13 is set to be opposite to each other with respect to adjacent blocks.

FIG. 7 is a diagram illustrating a switching order in each of the change-over switches 23-0 to 23-15 provided on the transmission conductor group 12 side. In the change-over switch 23-0 corresponding to the block B0, the transmission conductor 11 that is a signal supply destination is switched in the order of Y ₃ , Y ₂ , Y ₁ , Y ₀ . In the changeover switch 23-1 corresponding to the block B 1, the transmission conductor 11 that is the signal supply destination is Y ₄ , Y ₅ , Y ₆ , Y, opposite to the switching order of the transmission conductors 11 in the adjacent block B 0. It is switched in the order of ₇ . Similarly, in the changeover switch 23-2 corresponding to the block B2, the transmission conductor 11 that is the signal supply destination is Y ₁₁ , Y ₁₀ , Y, opposite to the switching order of the transmission conductors 11 in the adjacent block B1. _9, are switched in the order of Y _8. In the change-over switch 23-3 corresponding to the block B3, the transmission conductor 11 serving as a signal supply destination is opposite to the switching order of the transmission conductors 11 in the adjacent block B2, and Y ₁₂ , Y ₁₃ , Y ₁₄ , Y _It can be switched in the order of ₁₅ . In this way, in the change-over switches corresponding to the blocks up to the block B15, the transmission conductors 11 to which signals are supplied are switched in the order opposite to the switching order of the transmission conductors 11 in the adjacent blocks.

By paying attention to two adjacent blocks by performing the switching operation of the transmission conductor 11 in this way, when attention is paid to two adjacent transmission conductors 11 (for example, block B0 and block B1) in these two blocks. Since the timings at which the two transmission conductors 11) indicated by Y ₃ and Y ₄ are selected can be made to coincide with each other, even when the finger is moving at high speed, The detection range can be avoided from being divided into two areas as indicated by E in FIG.

FIG. 8 is a diagram illustrating the switching order in each of the change-over switches 31-0 to 31-15 provided on the reception conductor group 14 side. In selector switch 31-0 corresponding to the block D0, the reception conductors 13 to take out a signal is switched in the order of _{X 0, X 1, X 2} , X 3, X 4, X 5, X 6, X 7. In the changeover switch 31-1 corresponding to the block D 1, the reception conductor 13 for extracting a signal is X ₁₅ , X ₁₄ , X ₁₃ , X ₁₂ , X ₁₂ , contrary to the switching order of the reception conductors 13 in the adjacent block D 0. ₁₁ , X ₁₀ , X ₉ , X ₈ are switched in this order. Similarly, in the changeover switch 31-2 corresponding to the block D2, the reception conductor 13 for extracting a signal is opposite to the switching order of the reception conductors 13 in the adjacent block D1, and X ₁₆ , X ₁₇ , X ₁₈ , X ₁₉ , X ₂₀ , X ₂₁ , X ₂₂ , X ₂₃ are switched in this order. In selector switch 31-3 corresponding to the block D3, the reception conductors 13 to take out a signal, as opposed to switching order of the reception conductors 13 of adjacent blocks _{D2, X 31, X 30,} X 29, X 28, X ₂₇ , X ₂₆ , X ₂₅ , X ₂₄ can be switched in this order. In this way, in the change-over switches corresponding to the blocks up to the block D15, the reception conductors 11 from which signals are extracted are switched in the order opposite to the switching order of the reception conductors 11 in the adjacent blocks.

By paying attention to two adjacent blocks by performing the switching operation of the reception conductor 13 in this way, when attention is paid to two adjacent reception conductors 13 (for example, block D1 and block D2) in these two blocks. Since the timing at which the two receiving conductors 13) indicated by X ₁₅ and X ₁₆ are selected can be made coincident with each other, even if the finger is moving at high speed, The detection range can be avoided from being divided into two areas as indicated by E in FIG.

  FIG. 9 is a diagram showing a detection result when the fingertip is placed on the sensor unit 10 so as to include the boundary between the two blocks D0 and D1, and the position of the fingertip moves at high speed in the upward direction. is there. As described above, in these two blocks D0 and D1, since the reception conductor is switched in the direction toward the boundary, as shown in FIG. 9A, the fingertip placed so as to include the boundary is placed. In the case of high-speed movement in the upward direction, as shown in FIG. 9B, the detection position of the fingertip is shifted upward as it approaches the boundary, but detection corresponding to each of the two blocks D0 and D1 The ranges d1 and d2 are not divided.

  FIG. 10 is a diagram illustrating the switching timing of the transmission conductor 11. In FIG. 10, T is a time interval (period) for switching the selection state of the transmission conductor 11. Since each block of the transmission conductor group 12 includes four transmission conductors 11, a switching operation for these four transmission conductors 11 is performed at time 4T, and then the switching operation is repeated in the same order at time 4T. .

  FIG. 11 is a diagram showing the switching timing of the receiving conductor 13. In FIG. 11, t is a time interval (period) for switching the selection state of the reception conductor 13. Since each block of the reception conductor group 14 includes eight reception conductors 13, a switching operation for these eight reception conductors 13 is performed at time 8t, and then the switching operation is repeated in the same order at time 8t. . The time 8t corresponds to the switching period T of the transmission conductor 12, and the transmission conductor 11 is switched every time the switching operation for the eight reception conductors 13 is completed.

  As described above, in the position detection device 100 of the present embodiment, each of the plurality of transmission conductors 11 and the plurality of reception conductors 13 is divided into a plurality of blocks (groups), and the transmission conductor 11 or the reception conductor 13 is divided into each block. And switching the selected conductor in a predetermined direction, the switching directions of the conductors in each of the two adjacent blocks are opposite to each other. Therefore, the conductor selection timing in the vicinity of the boundary between these two blocks can be adjusted. Even if the indicator moves, the area detected corresponding to this indicator is not divided by the timing of switching the conductor, and the position of the indicator is erroneously detected. Can be prevented.

  In addition, when the receiving conductors 13 on the side for detecting the electrical characteristics are grouped, the time lag for detecting the electrical characteristics of the receiving conductors 13 arranged in the vicinity of the boundary between adjacent blocks can be reduced. It is possible to prevent erroneous detection of the position of the indicator, which is caused by the timing at which the reception conductor 13 is switched.

  In addition, when the transmission conductors 11 on the side that supplies a signal of a predetermined frequency are grouped, a time lag in supplying signals to the transmission conductors 11 arranged in the vicinity of the boundary between adjacent blocks can be reduced. In addition, it is possible to prevent erroneous detection of the position of the indicator, which occurs when the timing of switching the transmission conductor 11 is shifted.

(Second Embodiment)
By the way, in 1st Embodiment, the change of the transmission conductor 11 in each of the change-over switches 23-0 to 23-15 provided in the transmission conductor group 12 side, and the change-over switch 31- provided in the reception conductor group 14 side. Switching of the receiving conductor 13 in each of 0 to 31-15 has been performed so as to always be in a certain direction. For example, paying attention to the changeover switch 23-0 corresponding to the block B0 on the transmission conductor group 12 side, the transmission conductor 11 serving as a signal supply destination is always switched in the order of Y ₃ , Y ₂ , Y ₁ , Y ₀ . When attention is paid to the changeover switch 31-0 corresponding to the block D0 on the reception conductor group 14 side, the reception conductor 13 from which signals are extracted is always X ₀ , X ₁ , X ₂ , X ₃ , X ₄ , X ₅ , X _6. , X ₇ in this order. This switching order may be reversed every time the conductor to be switched makes a round.

FIG. 12 is a diagram illustrating a specific switching order when the switching order of conductors in the selector switches 23-0 to 23-15 provided on the transmission conductor group 12 side is reversed for each frame. Note that the time length at which selection of all the transmission conductors 11 included in each block ends corresponds to one frame (the same applies to FIG. 13). For example, focusing on the block B0, in the frame 1, the transmission conductor 11 is switched in the order of Y ₃ , Y ₂ , Y ₁ , Y ₀ , but in frame 2, the switching order is reversed and the transmission conductor 11 is switched to Y ₀ , Y It is switched in the order of ₁ , Y ₂ , Y ₃ . Thereafter, the transmission conductors 11 are switched in the same order as the frame 1 in the third and subsequent odd frames, and the transmission conductors 11 are switched in the same order as the frame 2 in the fourth and subsequent even frames.

FIG. 13 is a diagram illustrating a specific switching order when the switching order of conductors in the selector switches 31-0 to 31-15 provided on the reception conductor group 14 side is reversed for each frame. For example, when focusing on the block D0, in the frame 1, the receiving conductor 13 is switched in the order of X ₀ , X ₁ , X ₂ , X ₃ , X ₄ , X ₅ , X ₆ , X ₇ , but in the frame 2 the switching order. And the receiving conductor 13 is switched in the order of X ₇ , X ₆ , X ₅ , X ₄ , X ₃ , X ₂ , X ₁ , X ₀ . Thereafter, the reception conductors 13 are switched in the same order as the frame 1 in the third and subsequent odd frames, and the reception conductors 13 are switched in the same order as the frame 2 in the fourth and subsequent even frames.

  As described above, when the switching direction of the conductor is reversed for each frame, the distortion of the detection range when the detected object moves on the surface of the sensor unit 10 can be reduced by averaging between the frames. Note that the switching order of the transmission conductors 11 on the transmission conductor group 12 side shown in FIG. 12 is reversed for each frame, and the switching order of the reception conductors 13 on the reception conductor group 14 side shown in FIG. 13 is reversed for each frame. Although the method of making it carry out may be implemented simultaneously, you may make it implement only either one.

(Third embodiment)
In each of the embodiments described above, a signal is selectively supplied to one transmission conductor 11 in each block. However, a signal is supplied to two (or more) transmission conductors 11 at the same time. You may make it do. When signals are supplied to the two transmission conductors 11 at the same time, the signal level (current value) output from the reception conductor 13 also increases, so that the SN ratio can be improved.

  In each of the above-described embodiments, the current value output from one receiving conductor 13 is detected in each block, but output from two adjacent (or more) receiving conductors 13 is output. The detected current value may be detected. In this case, reception sensitivity can be improved.

  When signals are simultaneously supplied to the two transmission conductors 11, it is desirable to simultaneously detect the current values output from the two reception conductors 13 in order to match the vertical and horizontal aspects of the detection data. In addition, when signals are supplied to the two transmission conductors 11 simultaneously, the curve (envelope) of the detection signal corresponding to the detection object is slower (blurred) than when signals are supplied to the single transmission conductor 11. The level change of the detection signal between the detection cross points becomes gentle and the linearity is improved. In other words, when the fingertip is moved by lightly touching the surface of the sensor unit 10, there is an effect that when the contact coordinates are calculated, the change becomes smooth.

FIG. 14 is a diagram showing a specific switching order when two receiving conductors 13 are simultaneously selected. In the figure, the numbers “16 to 32” correspond to the receiving conductors 13 indicated by X _{16 to} X ₃₂ . In FIG. 14, the switching order of the reception conductors 13 is shown mainly focusing on two adjacent blocks D2 and D3. In addition, one receiving conductor 11 (X ₂₄ ) existing at the boundary between two adjacent blocks D2 and D3 belongs to both the blocks D2 and D3, and is selected at a predetermined timing in each block. It has become. In the example shown in FIG. 14, in the block D2, two transmission conductors 13 are selected and switched in the order of arrangement. On the other hand, in the adjacent block D3, the point that two transmission conductors 13 are selected is the same, but the order of selection is not the order of arrangement, but zigzag so as to partially return to the order of arrangement. I try to switch. Thereby, it is possible to avoid simultaneously selecting the reception conductor 13 (X ₂₄ ) included in the two blocks D2 and D3 in the two blocks D2 and D3.

In the example shown in FIG. 14, the reception conductor 13 is switched to zigzag only for the block D3 of the two blocks D2 and D3. However, the selection timing of the common reception conductor 13 (X ₂₄ ) is shifted. The same switching may be performed in both blocks D2 and D3. In the example illustrated in FIG. 14, the specific example of the switching method of the reception conductor 13 has been described. However, the transmission conductor 11 may be switched similarly.

  In addition, this invention is not limited to the said embodiment, A various deformation | transformation implementation is possible within the range of the summary of this invention. For example, in each of the embodiments described above, the case where the transmission conductor 11 and the reception conductor 13 are orthogonal to each other has been described. However, the present invention can also be applied to a case where the transmission conductor 11 and the reception conductor 13 intersect at an angle other than 90 degrees.

  Further, in each of the above-described embodiments, the eight reception conductors 13 included in each block of the reception conductor group 14 are switched during the period T in which the transmission conductors 11 are switched. During the switching period t, the four transmission conductors 11 included in each block of the transmission conductor group 12 may be switched.

  In each of the embodiments described above, each of the transmission conductor group 12 and the reception conductor group 14 is grouped into 15 blocks. However, the number of blocks can be changed. The number of blocks of the conductor group 14 may be varied. Further, a configuration for detecting the current for each reception conductor 13 included in the reception conductor group 14 may be provided so that the switching operation on the reception conductor 13 side may be omitted.

  In the above-described embodiments, a multi-frequency signal is assumed as a signal supplied to the transmission conductor 11 side. However, the supply signal may be a signal other than the multi-frequency signal. For example, the same effect can be obtained also in a position detection apparatus that supplies a plurality of spread code signals, specifically, spread spectrum codes to the transmission conductors 11 divided into blocks. The same effect can also be obtained in the position detection apparatus that supplies the transmission signal 11 divided into each block by shifting the phase of a specific spreading code.

  Further, in each of the above-described embodiments, the present invention is applied to the capacitive position detection apparatus 100 that supplies a signal to the transmission conductor 11 side and detects a current output from the reception conductor 13 side. As disclosed in Japanese Patent Application Laid-Open No. 2009-162538, a capacitance type position detection that detects the position of an indicator by detecting the capacitance values of two types of conductors (electrodes) that intersect each other. The present invention can also be applied to an apparatus. In addition, the present invention can be applied to any position detection device that switches conductors in order even if a method other than a capacitance method is adopted.

  According to the present invention, when a plurality of conductors constituting a conductor pattern are divided into a plurality of groups, a conductor is selected for each group and the selected conductor is switched in a predetermined direction, each of the two adjacent groups Since the switching direction of the conductors is opposite to each other, the selection timing of the conductors in the vicinity of the boundary between these two groups can be matched, and even when the indicator moves, it is detected corresponding to this indicator. Therefore, it is possible to prevent erroneous detection of the position of the indicator.

DESCRIPTION OF SYMBOLS 100 Position detection apparatus 10 Sensor part 20 Transmission part 30 Reception part 40 Control circuit 11 Transmission conductor 12 Transmission conductor group 13 Reception conductor 14 Reception conductor group 15 1st glass substrate 16 Spacer 17 2nd glass substrate 21 Clock generation circuit 22 Multifrequency signal Supply circuit 23 Transmission conductor selection circuit 22-0, 22-1,..., 22-15 Signal generation unit 23-0, 23-1, ... 23-15 Changeover switch 31 Reception conductor selection circuit 31-0 , 31-1,..., 31-15 changeover switch 32 amplifier circuit 32-1, 32-1,..., 32-15 current-voltage conversion circuit (I / V)
32A selector switch 33 Analog-digital conversion circuit (A / D)
34 signal detection circuit 35 position calculation circuit

Claims (6)

A first conductor pattern comprising a plurality of conductors arranged in a first direction;
A second conductor pattern composed of a plurality of conductors arranged in a second direction intersecting the first direction;
A signal transmitter connected to the first conductor pattern and supplying a spread spectrum code to the first conductor pattern;
A signal detector that detects a signal generated in the second conductor pattern based on a position instruction by an indicator,
A direction in which a plurality of conductors constituting the second conductor pattern are divided into at least a first conductor group and a second conductor group adjacent to each other and each conductor constituting the first conductor group is selected. And selecting the plurality of conductors so that the directions in which the respective conductors constituting the second conductor group are selected are different from each other and arranged on the adjacent sides of the first conductor group and the second conductor group A position detection device comprising: a conductor selection unit that selects the plurality of conductors so that the switching timings of the conductors matched with each other. In claim 1,
Dividing the plurality of conductors constituting the first conductor pattern into at least a first conductor group and a second conductor group adjacent to each other;
The first conductor pattern is divided into the first conductor group and the second conductor group, and the signal transmission unit is different for each of the first conductor group and the second conductor group. A position detecting device, wherein the spread spectrum code is supplied in parallel. In claim 1 or 2,
A signal generated in the second conductor pattern based on the position indication by the indicator is a current value,
The signal detection unit detects the position by converting the current value into a voltage value. In claim 1,
The conductor selection unit makes one round of selection of each conductor in the direction of selecting each conductor constituting the first conductor group and the direction of selecting each conductor constituting the second conductor group. A position detecting device that reverses the order of selection every time. In claim 1,
The conductor selection unit performs selection of the conductors in at least one of the first conductor group and the second conductor group on a plurality of adjacently arranged conductors. . A first conductor pattern comprising a plurality of conductors arranged in a first direction; and a second conductor pattern comprising a plurality of conductors arranged in a second direction intersecting the first direction. A position detection method in a position detection device, comprising:
A signal transmission unit supplies a spread spectrum code to the first conductor pattern,
Each of the plurality of conductors constituting the second conductor pattern is divided into at least a first conductor group and a second conductor group adjacent to each other, and each of the first conductor group is constituted by a conductor selection unit. The plurality of conductors are selected such that a direction in which a conductor is selected and a direction in which each conductor constituting the second conductor group is selected are different from each other, and the first conductor group and the second conductor group Selecting the plurality of conductors so that the switching timings of the conductors arranged on the adjacent sides match,
A position detection method comprising: detecting a signal generated in the second conductor pattern by a signal detection unit based on a position instruction by an indicator.

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