JP6278888B2 - INPUT DEVICE, ITS CONTROL METHOD, AND PROGRAM - Google Patents

Description

  The present invention relates to an input device that inputs information according to the proximity state of an object using a change in capacitance and the like, and a control method and program thereof, and in particular, in various information devices such as a computer, a finger, a pen, etc. The present invention relates to an input device that inputs information according to the operation.

  Sensors that detect changes in capacitance can detect the proximity of an object (finger, pen, etc.) with a simple configuration, so user interface devices for various electronic devices such as touchpads for notebook computers and touch panels for smartphones Widely used in

  The following Patent Document 1 describes a touch panel device including a touch panel unit in which a plurality of electrodes are arranged. A scanning electrode is determined from a plurality of electrodes of the touch panel unit, and the touch panel unit is operated on the determined scanning electrode, whereby a measurement value reflecting a change in capacitance of each electrode is acquired. The presence or absence of a touch on the touch panel unit is detected based on the acquired measurement value.

International Publication No. 2012/117437

  In the user interface device using a touch panel, various finger operations such as tapping, flicking, and swiping are defined, and the time for touching the finger and the speed, distance, direction, etc. for moving the finger position are analyzed. Thus, a command corresponding to the operation of the finger is input. Therefore, it is necessary not only to detect the finger contact position for each cycle, but also to track the same finger contact position over a plurality of cycles and obtain the locus thereof.

  However, since an input device such as a touch panel is configured to detect an object close to the detection surface of the sensor with high sensitivity, there is a problem that the sensor is particularly susceptible to electromagnetic noise from the outside. For example, in the case of the capacitance type sensor described above, since the change in the capacitance of the electrode due to the proximity of the object is detected as a minute change in the amount of charge, erroneous detection of the coordinates and contact state of the object due to the influence of noise is detected. It is likely to occur. When such a false detection occurs, an object that is not actually a finger may be tracked as the finger position.

  FIG. 5 is a diagram illustrating an example in which the position of the finger is erroneously tracked due to noise or the like. In FIG. 5, “N1” to “N4” indicate coordinates erroneously detected as finger contact positions due to the influence of noise. “A1” to “A5” indicate the coordinates of the contact position of the finger A, and “B6” to “B9” indicate the coordinates of the contact position of the finger B. The number attached to each code indicates the number of cycles in which the coordinates are detected. For example, “N1” and “A1” are different coordinates detected in the same cycle “1”.

  In order to track the contact position of the same finger, it is necessary to correctly associate the coordinates detected in the new cycle and the coordinates detected in the previous cycle with the same fingers. In the example of FIG. 5, this association is performed based on the distance between coordinates. That is, the coordinates detected in the new cycle are linked to the closest coordinates detected in the previous cycle. Therefore, in the cycles “1” to “4”, the adjacent coordinates “A1” to “A4” are linked, and the remaining coordinates “N1” to “N4” are linked. Since the coordinates “A1” to “A4” are the coordinates of the finger A, this association is correct. However, since the coordinates “N1” to “N4” are coordinates erroneously detected due to noise, if these are linked as finger coordinates, the noise is erroneously recognized as a finger operation.

  In the example of FIG. 5, the finger A that has been in contact with the sensor coordinates “A1” to “A5” in cycles “1” to “5” is separated from the sensor after cycle “6”. However, from this cycle “6”, another finger B newly starts to contact the coordinate “B6” of the sensor. Since the coordinate “B6” of the cycle “6” is closest to the coordinate “A5” of the cycle “5”, the coordinate “6” is associated with the coordinate “A5”. As a result, the trajectory of the finger A at the coordinates “A1” to “A5” and the trajectory of the finger B at the coordinates “B6” to “B9” are erroneously processed as the same finger trajectory.

  The present invention has been made in view of such circumstances, and an object thereof is to provide an input device capable of correctly tracking the movement of the coordinates of the same object in contact with the detection surface, and a control method and program thereof.

  An input device according to a first aspect of the present invention is an input device that inputs information according to the proximity state of an object to a detection surface, and detects a proximity state of the object at a plurality of positions on the detection surface. A sensor control unit that controls the sensor unit to perform a periodic detection operation for detecting the proximity state of the object at the plurality of positions every cycle, and the sensor for each cycle of the detection operation. A coordinate acquisition unit that acquires the coordinates of the position of the object close to the detection surface based on the detection result of the unit, a linking unit that links the coordinates of the same object acquired in a different cycle of the detection operation, An error detecting unit for detecting an error in linking with respect to the series of coordinates based on the series of the coordinates linked by the linking unit over a series of the detection operation; And a error correction unit for correcting the errors of said detected linkage in over detector.

  According to the above configuration, based on the series of coordinates of the same object tied by the tying unit over a series of cycles of the detection operation, an error in pegging with respect to the series of coordinates is detected, The detected error of the association is corrected by the error correction unit. Therefore, the movement of the coordinates of the same object that contacts the detection surface is correctly tracked.

Preferably, the error detection unit calculates an evaluation value according to a temporal change in the position of the object adjacent to the detection surface based on the series of coordinates linked by the linking unit, When the calculated evaluation value satisfies a predetermined error determination condition, it may be determined that there is an error in linking to the series of coordinates.
Thereby, the presence or absence of a pegging error with respect to the series of coordinates is determined from the temporal change in the position of the object close to the detection surface.

Preferably, the error detection unit may calculate at least one of an evaluation value according to a speed of an object close to the detection surface and an evaluation value according to the acceleration of the object.
Thereby, the presence or absence of a pegging error with respect to the series of coordinates is determined from the speed and acceleration of the object close to the detection surface.

Preferably, the error detection unit acquires the first coordinate acquired in one cycle of the detection operation and the cycle acquired immediately before the one cycle, and is associated with the first coordinate. An evaluation value corresponding to the acceleration is calculated based on the second coordinate and the third coordinate acquired in the cycle two before the one cycle and linked to the second coordinate. Good.
As a result, the association error is detected using an evaluation value corresponding to the acceleration of the object indicated by the coordinates of three consecutive cycles.

Preferably, the error detection unit acquires the first coordinate acquired in one cycle of the detection operation and the cycle acquired immediately before the one cycle, and is associated with the first coordinate. An evaluation value corresponding to the speed may be calculated based on the second coordinates.
Accordingly, the association error is detected using an evaluation value corresponding to the speed of the object indicated by the coordinates of two consecutive cycles.

  Preferably, the error detection unit may determine that there is an error in the association between the first coordinate and the second coordinate when the evaluation value satisfies a predetermined error determination condition.

Preferably, the associating unit may assign the same identification code to the coordinates of the same object acquired in different cycles of the detection operation. When the error correction unit has an error in associating the first coordinate acquired in one cycle of the detection operation with the second coordinate acquired in the cycle immediately before the one cycle. When it is determined by the error detection unit, an identification code different from the second coordinate may be assigned to the first coordinate.
Thereby, when it is determined that there is an error in associating the first coordinate acquired earlier and the second coordinate acquired later, the identification code of the first coordinate acquired later Is changed to an identification code different from the previously acquired second coordinates.

Preferably, when the error correction unit determines that there is an error in associating the first coordinate with the second coordinate, the error correction unit includes the identification code in the cycle in which the first coordinate is acquired. If the assigned number has reached a predetermined upper limit value, the assignment of the identification code to the first coordinate may be stopped.
As a result, the number of objects to be tracked of coordinate movement is limited to the upper limit value.

  According to a second aspect of the present invention, a computer includes a sensor unit that detects a proximity state of an object at a plurality of positions on a detection surface, and a computer controls an input device that inputs information according to the proximity state of the object to the detection surface. On how to do. The control method of the input device includes a step of controlling the sensor unit so as to perform a periodic detection operation for detecting a proximity state of an object at the plurality of positions for each cycle, and for each cycle of the detection operation. Acquiring the coordinates of the position of the object close to the detection surface based on the detection result of the sensor unit, associating the coordinates of the same object acquired in a different cycle of the detection operation, Detecting an error of linking to the series of coordinates based on the series of coordinates linked by the step of linking the coordinates over a series of detection operations; and detecting the error And correcting the pegging error detected in the step.

  Preferably, the step of detecting the error includes an evaluation according to a temporal change in the position of the object adjacent to the detection surface based on the series of coordinates linked by the step of linking the coordinates. A value may be calculated, and when the calculated evaluation value satisfies a predetermined error determination condition, it may be determined that there is an error in linking to the series of coordinates.

  Preferably, the step of detecting the error may calculate at least one of an evaluation value according to a speed of an object close to the detection surface and an evaluation value according to the acceleration of the object.

  Preferably, the step of detecting the error includes the first coordinate acquired in one cycle of the detection operation and the first coordinate acquired in the cycle immediately before the one cycle. The evaluation value corresponding to the acceleration is obtained based on the attached second coordinate and the third coordinate acquired in the cycle two prior to the one cycle and linked to the second coordinate. It may be calculated.

  Preferably, the step of detecting the error includes the first coordinate acquired in one cycle of the detection operation and the first coordinate acquired in the cycle immediately before the one cycle. An evaluation value corresponding to the speed may be calculated based on the attached second coordinates.

  Preferably, the step of detecting the error may determine that there is an error in associating the first coordinate with the second coordinate when the evaluation value satisfies a predetermined error determination condition.

  Preferably, the step of associating the coordinates may assign the same identification code to the coordinates of the same object acquired in different cycles of the detection operation. The step of correcting the error includes an error in associating the first coordinate acquired in one cycle of the detection operation with the second coordinate acquired in the cycle immediately before the one cycle. If the error is detected in the step of detecting the error, an identification code different from the second coordinate may be assigned to the first coordinate.

  Preferably, in the step of correcting the error, when it is determined that there is an error in associating the first coordinate with the second coordinate, the cycle in which the first coordinate is acquired If the number of assigned identification codes has reached a predetermined upper limit value, the assignment of identification codes to the first coordinates may be stopped.

  A third aspect of the present invention relates to a program for causing a computer to execute the control method for the input device according to the second aspect of the present invention.

  According to the present invention, it is possible to correctly track the movement of the coordinates of the same object that contacts the detection surface.

It is a figure which shows an example of a structure of the input device which concerns on embodiment of this invention. It is the figure which illustrated the speed and acceleration calculated | required from the coordinate of 3 continuous cycles. It is a flowchart for demonstrating the correction | amendment of allocation of an identification code, and the linkage | linking error of a coordinate in the input device concerning embodiment of this invention. It is a flowchart for demonstrating the process in connection with the detection and correction | amendment of a coordinate link | linking error. It is the figure which showed the example which tracks the contact position of a finger accidentally by noise etc.

<First Embodiment>
FIG. 1 is a diagram illustrating an example of a configuration of an input device according to an embodiment of the present invention.
The input device illustrated in FIG. 1 includes a sensor unit 10, a processing unit 20, a storage unit 30, and an interface unit 40. The input device according to this embodiment is a device that inputs information according to the proximity state by bringing an object such as a finger or a pen close to a detection surface provided with a sensor. Note that “proximity” in the present specification includes both being close in a contact state and being close in a non-contact state.

[Sensor unit 10]
The sensor unit 10 detects the proximity state of an object such as a finger or a pen at a plurality of detection positions distributed on the detection surface. For example, the sensor unit 10 includes a sensor matrix 11 in which a capacitive sensor element (capacitor) 12 whose capacitance changes according to the proximity of an object is formed in a matrix, and a capacitance according to the capacitance of the capacitive sensor element 12. A detection data generation unit 13 that generates detection data and a drive unit 14 that applies a drive voltage to the capacitive sensor element 12 are included.

  The sensor matrix 11 includes a plurality of drive electrodes Lx extending in the vertical direction and a plurality of detection electrodes Ly extending in the horizontal direction. The plurality of drive electrodes Lx are arranged in parallel in the horizontal direction, and the plurality of detection electrodes Ly are arranged in parallel in the vertical direction. The plurality of drive electrodes Lx and the plurality of detection electrodes Ly intersect in a lattice pattern and are insulated from each other. The capacitive sensor element 12 is formed near the intersection of the drive electrode Lx and the detection electrode Ly. In the example of FIG. 1, the shape of the electrodes (Lx, Ly) is drawn in a strip shape, but other arbitrary shapes (such as a diamond pattern) may be used.

  The drive unit 14 applies a drive voltage to each capacitive sensor element 12 of the sensor matrix 11. Specifically, the drive unit 14 selects one drive electrode Lx in order from the plurality of drive electrodes Lx according to the control of the processing unit 20, and periodically changes the potential of the selected one drive electrode Lx. . When the potential of the drive electrode Lx changes within a predetermined range, the drive voltage applied to the capacitive sensor element 12 formed near the intersection of the drive electrode Lx and the detection electrode Ly changes within the predetermined range. Charging or discharging occurs in the capacitive sensor element 12.

  The detection data generation unit 13 generates detection data corresponding to the charge transmitted in each detection electrode Ly when the capacitive sensor element 12 is charged or discharged in accordance with the application of the drive voltage by the drive unit 14. That is, the detection data generation unit 13 samples the charge transmitted through each detection electrode Ly at a timing synchronized with the periodic change of the drive voltage of the drive unit 14, and generates detection data according to the sampling result. To do.

For example, the detection data generation unit 13 converts a capacitance-voltage conversion circuit (CV conversion circuit) that outputs a voltage corresponding to the capacitance of the capacitive sensor element 12 and the output signal of the CV conversion circuit into a digital signal. And an analog-digital conversion circuit (AD conversion circuit) that outputs the detection data.
The CV conversion circuit samples the charge transmitted through the detection electrode Ly according to the control of the processing unit 20 each time the driving voltage of the driving unit 14 is periodically changed to charge or discharge the capacitive sensor element 12. . Specifically, every time positive or negative charge is transmitted at the detection electrode Ly, the CV conversion circuit transfers this charge or a charge proportional thereto to the reference capacitor and generates it in the reference capacitor. A signal corresponding to the voltage is output. For example, the CV conversion circuit outputs a signal corresponding to an integrated value or an average value of charges periodically transmitted through the detection electrode Ly or charges proportional thereto. The AD conversion circuit converts the output signal of the CV conversion circuit into a digital signal at a predetermined period according to the control of the processing unit 20 and outputs it as detection data.

  In addition, although the sensor part 10 shown in the above-mentioned example detects the proximity | contact of an object by the change of the electrostatic capacitance (mutual capacitance) which arises between electrodes (Lx, Ly), it is not restricted to this example, others The proximity of the object may be detected by various methods. For example, the sensor unit 10 may be a system that detects a capacitance (self-capacitance) generated between the electrode and the ground due to the approach of an object. In the case of a method for detecting self-capacitance, a drive voltage is applied to the detection electrode. Further, the sensor unit 10 is not limited to the electrostatic capacity method, and may be, for example, a resistance film method or an electromagnetic induction method.

[Processing unit 20]
The processing unit 20 is a circuit that controls the overall operation of the input device, and includes, for example, a computer that performs processing according to an instruction code of a program stored in the storage unit 30, and a logic circuit that implements a specific function. Composed. All of the processing of the processing unit 20 may be realized by a computer and a program, or part or all of the processing may be realized by a dedicated logic circuit.

  In the example of FIG. 1, the processing unit 20 includes a sensor control unit 21, a two-dimensional data generation unit 22, a coordinate acquisition unit 23, a contact state determination unit 24, a linking unit 25, an error detection unit 26, An error correction unit 27 is included.

  The sensor control unit 21 causes the sensor unit 10 to perform a periodic detection operation for detecting the proximity state of the object at each cycle at a plurality of detection positions (each capacitive sensor element 12 of the sensor matrix 11) on the detection surface. Control. Specifically, the sensor control unit 21 periodically selects the drive electrode and generation of the pulse voltage in the drive unit 14 and the detection electrode selection and detection data generation in the detection data generation unit 13 at appropriate timings. These circuits are controlled as done.

  The two-dimensional data generating unit 22 generates two-dimensional data 31 in a matrix format including a plurality of detection data indicating the degree of proximity of an object at a plurality of positions on the operation surface based on the detection result of the sensor unit 10, Store in the storage unit 30.

  For example, the two-dimensional data generation unit 22 stores the detection data output from the sensor unit 10 in a storage area (current value memory) of the storage unit 30 in a matrix format. The two-dimensional data generation unit 22 calculates a difference between the detection data in the matrix format stored in the current value memory and the base value in the matrix format stored in advance in another storage area (base value memory) of the storage unit 30; These calculation results are stored in the storage unit 30 as two-dimensional data 31. The base value memory stores a value (base value) that serves as a reference for detection data in a state where no object is close to the detection surface. The two-dimensional data 31 represents the amount of change in detection data from a state where the object is not close to the detection surface.

  The coordinate acquisition unit 23 acquires the coordinates P of the position of the object close to the detection surface based on the detection result of the sensor unit 10 for each cycle of the detection operation in the sensor unit 10. For example, the coordinate acquisition unit 23 specifies the proximity region of the object on the detection surface based on the two-dimensional data 31 generated by the two-dimensional data generation unit 22, and the shape of the specified proximity region and the data in the proximity region The coordinates P of the object are calculated from the value distribution and the like.

  The contact state determination unit 24 determines the contact state of the object whose coordinates are acquired by the coordinate acquisition unit 23 on the detection surface based on the detection result of the sensor unit 10 for each cycle of the detection operation in the sensor unit 10. The contact state value T indicating the determination result is acquired. For example, the contact state determination unit 24 makes the object (finger) contact the detection surface based on the area of the proximity region on the detection surface of the object for which the coordinate P is calculated, the size of the data value in the proximity region, and the like. It is determined whether or not.

  Further, the contact state determination unit 24 counts the number of “fingers” (contact index M) in contact with the detection surface of the sensor unit 10 based on the contact state value T acquired for each object.

  The linking unit 25 performs a process of linking the coordinates of the same object acquired in different cycles of the detection operation of the sensor unit 10. For example, the associating unit 25 assigns the same identification code i to the coordinates of the same object acquired in different cycles of the detection operation by the sensor unit 10. The identification code i is information for tracking the coordinates of the same object over a plurality of cycles. For example, the associating unit 25 calculates the distance between the coordinate P acquired in the previous cycle and the coordinate P newly acquired in the current cycle, and the previous coordinate P and the current coordinate having the shortest distance from each other. A combination with P is specified. Then, the associating unit 25 assigns the same identification code i as the coordinate P of the previous cycle with the shortest distance to the coordinate P of the current cycle.

  Further, the associating unit 25 assigns an identification code i for the contact state value T together with the coordinates P. For example, the associating unit 25 assigns the same identification code i to the data D including the coordinates P and the contact state value T in the same cycle of the same object over a plurality of cycles of the detection operation. That is, the associating unit 25 treats the coordinates P and contact state values T of the same object acquired in the same cycle as one data D, and assigns an identification code i to the data D. Data D to which the identification code i is assigned in cycle n is denoted as “D [n] [i]”.

Specifically, the associating unit 25 assigns the identification code i as follows.
First, the associating unit 25 treats the coordinates P and contact state values T acquired for the same object in the cycle n as one data C, and assigns a temporary identification code k to the data C. Data C to which a temporary identification code k is assigned in cycle n is denoted as “C [n] [k]”.
Next, the associating unit 25 assigns the coordinate P of the data D [n−1] [i] to which the identification code i was assigned in the previous cycle n−1 and the temporary identification code k in the current cycle n. The distance between the obtained data C [n] [k] and the coordinate P is calculated, and the data D [n−1] [i] and the data C [n] [k] having the shortest distance between the coordinates P are calculated. Identify combinations.
Then, the associating unit 25 uses the coordinates P and the contact state values T of the data C [n] [k] that are in the shortest distance relationship with the data D [n−1] [i] as the data D in the current cycle n. Substitute into [n] [i].

  Note that the associating unit 25 performs the cycle for data C [n] [k] (such as a finger newly touched in cycle n) in which the data D [n−1] [i] having the shortest distance relationship does not exist. Substitute into data D [n] [i] using an unassigned identification code i at n-1.

  The error detection unit 26 detects a pegging error for the series of coordinates P based on the series of coordinates P linked by the pegging unit 25 over a series of detection operations performed by the sensor unit 10. For example, the error detection unit 26 calculates the evaluation value E according to the temporal change in the position of the object close to the detection surface based on the series of coordinates P linked by the linking unit 25, and calculates When the evaluation value E satisfies a predetermined error determination condition, it is determined that there is an error in the linking to the series of coordinates P.

Specifically, the error detection unit 26 calculates an evaluation value E according to the speed and acceleration of an object close to the detection surface.
FIG. 2 shows the speed (V [n], V [n-1]) and acceleration (according to the coordinates (P [n], P [n-1], P [n-2]) of three consecutive cycles) It is the figure which illustrated A [n]). In FIG. 2, “P [n]”, “P [n−1]”, and “P [n-2]” are coordinates acquired in cycles n, n−1, and n−2, and are associated with each other. They are linked by the unit 25 (the same identification code i is assigned). Since each coordinate is acquired at a fixed time interval, the coordinates of two successive cycles represent the velocity vector of the object. In FIG. 2, “V [n]” represents a velocity vector of an object moving from the coordinate P [n−1] to the coordinate P [n], and “V [n−1]” represents the coordinate P [n−2]. Represents the velocity vector of the object moving from to the coordinate P [n−1].

  A vector “A [n]” that is a difference between the velocity vector V [n] and the velocity vector V [n−1] represents an acceleration vector of the object. The magnitude of the acceleration vector A [n] depends on the coordinate values (X [n], Y [n]), (X [n] of the coordinates P [n], P [n-1], P [n-2]. -1], Y [n-1]), (X [n-2], Y [n-2]).

  In order to omit the square root square root operation, the error detection unit 26 calculates the square of “| A [n] |” as the evaluation value E. The evaluation value E is expressed by the following formula.

  The error detection unit 26 determines that there is an error in the association between the coordinates P [n] and the coordinates P [n−1] when the evaluation value E calculated by the expression (2) satisfies a predetermined error determination condition. . Specifically, the error detection unit 26 determines that there is an association error when the evaluation value E is greater than the threshold value TH (that is, when | A [n] | is greater than the reference value).

  The error correction unit 27 corrects the associating error detected by the error detection unit 26. Specifically, the error correction unit 27 associates the coordinates P [n] acquired in the detection operation cycle n with the coordinates P [n−1] acquired in the immediately preceding cycle n−1. If the error detection unit 26 determines that there is an error in the attachment, an identification code i different from the coordinate P [n−1] is assigned to the coordinate P [n]. For example, the error correction unit 27 assigns an unassigned identification code i in the cycle n to the coordinate P [n]. As a result, the coordinate P [n] is treated as the coordinate of the object that newly contacts the detection surface in cycle n.

  However, when it is determined that there is an error in associating the coordinates P [n] and the coordinates P [n−1], the error correction unit 27 identifies the identification code in the cycle n from which the coordinates P [n] are acquired. If the number of assigned i (the number of coordinates to which the identification code i is assigned in the cycle n) has reached a predetermined upper limit value, the assignment of the identification code to the coordinate P [n] is stopped. In this case, for example, the error correction unit 27 initializes the coordinates P [n] where there is a linking error. This upper limit value is a value that sets the upper limit of the number of objects to be detected, and objects that have touched the upper limit value are excluded from the detection target.

[Storage unit 30]
The storage unit 30 stores constant data and variable data used for processing in the processing unit 20. When the processing unit 20 includes a computer, the storage unit 30 may store a program executed on the computer. The storage unit 30 includes, for example, a volatile memory such as a DRAM or SRAM, a nonvolatile memory such as a flash memory, a hard disk, or the like.

[Interface unit 40]
The interface unit 40 is a circuit for exchanging data between the input device and another control device (such as a control IC for an information device equipped with the input device). The processing unit 20 outputs information (such as object coordinate information and the number of objects) stored in the storage unit 30 from the interface unit 40 to a control device (not shown). Further, the interface unit 40 acquires a program executed in the computer of the processing unit 20 from a disk drive device (not shown) (device that reads a program recorded in a non-temporary recording medium), a server, or the like, and the storage unit 30 You may load it.

  Next, an operation for correcting an error in associating coordinates P in the input device having the above-described configuration will be described. FIG. 3 is a flowchart for explaining the assignment of the identification code i and the correction of the coordinate linking error in the input device according to the present embodiment.

ST100:
When starting the operation, the processing unit 20 initializes the data C and D indicating the coordinates P and the contact state value T of each object in each cycle, and substitutes the initial value 2 into the cycle n of the detection operation of the sensor unit 10. .

ST110:
The coordinate acquisition unit 23 acquires the coordinates P of the position of each object close to the detection surface based on the two-dimensional data 31 stored in the storage unit 30 as the detection result of the sensor unit 10 in the current cycle n.
The contact state determination unit 24 acquires, based on the two-dimensional data 31, a contact state value T indicating the contact state of each object whose coordinate P has been calculated with respect to the detection surface, and an object (finger) in contact with the detection surface. Are counted (contact index M).
The associating unit 25 assigns a temporary identification code k to the coordinates P and the contact state value T of each object, and stores them in the storage unit 30 as data C [n] [k].

ST120:
The associating unit 25 uses the coordinates P of the data D [n−1] [i] assigned the identification code i in the previous cycle n−1 and the data assigned the temporary identification code k in the current cycle n. The distance between the coordinates C [n] [k] and the coordinates P is calculated, and the combination of the data D [n−1] [i] and the data C [n] [k] having the shortest distance between the coordinates P is specified. To do. When the combination of the shortest distances is specified, the associating unit 25 uses the coordinates P and the contact state values T of the data C [n] [k] that are in the shortest distance relationship with the data D [n−1] [i]. Then, the data is substituted into data D [n] [i] in the current cycle n.

ST130:
The processing unit 20 assigns an initial value 0 to the object identification code i.

ST140:
The error detection unit 26 calculates an evaluation value E based on the coordinates P [n], P [n−1], and P [n−2] to which the identification code i is assigned by the associating unit 25, and the evaluation value E If the predetermined error determination condition is satisfied, it is determined that there is an error in the association between the coordinates P [n] and the coordinates P [n−1]. When the association error is detected by the error detection unit 26, the error correction unit 27 assigns an identification code i different from the coordinate P [n-1] to the coordinate P [n].

FIG. 4 is a flowchart for explaining in more detail the processing related to the detection and correction of the coordinate linking error in step ST140.
The error detection unit 26 performs data D [n] [i], D [n−1] [i], D [n−2] [D] in the last three consecutive cycles (n, n−1, n−2). i] is determined whether or not all of the contact state values T indicate that the “finger” is in contact (ST200). If all of the contact state values T indicate that the “finger” is in contact, the process proceeds to step ST210. Transition. If all the contact state values T in cycles n, n−1, and n−2 do not indicate that the “finger” is in contact, the error detection unit 26 cannot calculate the evaluation value E, and thus ends the process.

  In step ST210, the error detection unit 26 determines three coordinates P [n] included in the data D [n] [i], D [n-1] [i], and D [n-2] [i]. , P [n−1], and P [n−2], the evaluation value E of Equation (2) is calculated (ST210), and it is determined whether this evaluation value E is equal to or greater than the threshold value TH (ST220). ). If the evaluation value E is smaller than the threshold value TH, the error detection unit 26 determines that there is no association error, and ends the process.

When the evaluation value E is smaller than the threshold value TH, the error detection unit 26 determines that there is an error in the association between the coordinates P [n] and the coordinates P [n−1]. If a linking error is detected, the error correction unit 27 determines whether or not the number of identification codes i assigned in cycle n has reached the upper limit value (ST250). If the assigned number of identification codes i has reached the upper limit value, error correction unit 27 initializes data D [n] [i] of cycle n (ST260). On the other hand, when the number of assigned identification codes i has not reached the upper limit value, the error correction unit 27 uses the coordinates P [n] and the contact state value T included in the data D [n] [i] in which the association error is detected. Is substituted into data D using another identification code (ST270). For example, the error correction unit 27 substitutes these coordinates P [n] and the contact state value T for data D [n] using an unassigned identification code. Alternatively, the error correction unit 27 substitutes these coordinates P [n] and the contact state value T for data D [n] using another identification code in which the contact state value T indicates the non-contact state of the finger. Also good. As a result, the coordinates P [n] for which the pegging error is detected are handled as the coordinates of the object (finger) that newly contacts the detection surface in cycle n.
The above is the description of the process in step ST140.

ST150 to ST170:
In order to proceed to processing of the next object, the processing unit 20 adds “1” to the identification code i (ST150), and compares the identification code i with the contact index M (ST160). When the identification code i is smaller than the contact index M, there is an object (finger) that has not been processed yet, and thus the processing unit 20 returns to step ST140. When the identification code i is greater than or equal to the contact index M, all objects (fingers) have been processed, so the processing unit 20 adds “1” to the cycle n (ST170) and returns to step ST110.

  As described above, according to the input device according to the present embodiment, based on a series of coordinates P of the same object linked by the linking unit 25 over a series of detection operations by the sensor unit 10, An evaluation value E corresponding to a temporal change in the position of the object close to the detection surface is calculated. When the calculated evaluation value E satisfies a predetermined error determination condition, it is determined that there is an error in the linking with respect to the series of coordinates P, and the linking error is corrected by the error correction unit 27. As a result, since the error in associating the coordinates P can be detected and corrected from the temporal change in the position of the object close to the detection surface, the movement of the coordinates of the same object in contact with the detection surface can be correctly tracked. .

  Further, according to the input device according to the present embodiment, when the evaluation value E according to the acceleration of the object calculated based on the series of coordinates P satisfies the error determination condition, there is an error in associating the series of coordinates P. It is determined that there is. This makes it possible to correct coordinates moved at a certain acceleration or more as a linkage error, so that the movement of coordinates of an object (finger) that does not move at an extremely large acceleration can be correctly tracked.

  Furthermore, according to the input device according to the present embodiment, when it is determined that there is an error in the association between the previously acquired coordinate P [n−1] and the subsequently acquired coordinate P [n], The identification code i of the acquired coordinate P [n] is changed to an identification code different from the previously acquired coordinate P [n-1]. Thereby, whenever a new coordinate P is acquired, the association error can be detected and corrected for the new coordinate P. That is, since it is possible to detect and correct the coordinate P link error in parallel with the acquisition of the coordinate P without changing the previously acquired coordinate P link, the detection and correction of the link error. Can be performed at high speed with a simple procedure.

  Although various embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and includes various variations.

  In the embodiment described above, a value corresponding to the square of the magnitude of the acceleration (Equation (2)) is calculated as the evaluation value E, but the present invention is not limited to this. In another embodiment of the present invention, a value corresponding to the speed may be calculated as the evaluation value E. For example, by using the coordinates P [n] and P [n−1] of two successive cycles, the evaluation value E corresponding to the square of the magnitude of the speed can be calculated. This evaluation value E is expressed by the following formula.

  When detecting an error in coordinate linking using the evaluation value E shown in Expression (3), it is desirable to sufficiently shorten the cycle of the detection operation of the sensor unit 10. As a result, it becomes easy to catch an abnormal movement whose speed is extremely increased in a short time, and therefore it is possible to accurately detect a coordinate linking error even by a method using the evaluation value E according to the speed.

  Further, the input device of the present invention is not limited to a user interface device that inputs information by operating a finger or the like. That is, the input device of the present invention is widely applicable to devices that input information according to the proximity state of various objects not limited to the human body to the detection surface.

DESCRIPTION OF SYMBOLS 10 ... Sensor part, 11 ... Sensor matrix, 13 ... Detection data generation part, 14 ... Drive part, 20 ... Processing part, 21 ... Sensor control part, 22 ... Two-dimensional data generation part, 23 ... Coordinate acquisition part, 24 ... Contact State determination unit, 25 ... association unit, 26 ... error detection unit, 27 ... error correction unit, 30 ... storage unit, 31 ... two-dimensional data, 40 ... interface unit.

Claims (15)

An input device for inputting information according to the proximity state of an object to a detection surface,
A sensor unit for detecting a proximity state of an object at a plurality of positions on the detection surface;
A sensor control unit for controlling the sensor unit to perform a periodic detection operation for detecting the proximity state of the object at the plurality of positions every cycle;
A coordinate acquisition unit that acquires the coordinates of the position of the object close to the detection surface based on the detection result of the sensor unit for each cycle of the detection operation;
A stringing unit that links the coordinates of the same object acquired in different cycles of the detection operation;
An error detection unit that detects an error in linking with respect to the series of coordinates based on the series of the coordinates linked by the linking unit over a series of cycles of the detection operation;
Possess an error correcting unit for correcting the error of the association detected in the error detection unit,
The associating unit assigns the same identification code to the coordinates of the same object acquired in different cycles of the detection operation,
When the error correction unit has an error in associating the first coordinate acquired in one cycle of the detection operation with the second coordinate acquired in the cycle immediately before the one cycle. An input device characterized by assigning an identification code different from the second coordinate to the first coordinate when determined by the error detection unit . In the case where it is determined that there is an error in associating the first coordinates with the second coordinates, the error correction unit determines that the number of assigned identification codes in the cycle in which the first coordinates are acquired is if has reached the predetermined upper limit value, the input device according to claim 1, characterized in that to stop the allocation of identification codes for said first coordinate. The error detection unit calculates an evaluation value according to a temporal change in the position of an object close to the detection surface based on the series of coordinates linked by the linking unit, and the calculated evaluation 3. The input device according to claim 1, wherein when the value satisfies a predetermined error determination condition, it is determined that there is an error in associating the series of coordinates. The input device according to claim 3 , wherein the error detection unit calculates at least one of an evaluation value corresponding to a speed of an object close to the detection surface and an evaluation value corresponding to an acceleration of the object. The error detection unit includes a first coordinate acquired in one cycle of the detection operation and a second coordinate acquired in the cycle immediately before the one cycle and associated with the first coordinate. An evaluation value corresponding to the acceleration is calculated based on the coordinates and a third coordinate acquired in a cycle two before the one cycle and linked to the second coordinate. The input device according to claim 4 . The error detection unit includes a first coordinate acquired in one cycle of the detection operation and a second coordinate acquired in the cycle immediately before the one cycle and associated with the first coordinate. The input device according to claim 4 , wherein an evaluation value corresponding to the speed is calculated based on coordinates. Said error detection unit, when the evaluation value is a predetermined error determination condition is satisfied, the first coordinate and the claim 5 or linking the second coordinate, wherein the determining that there is an error 6. The input device according to 6 . A method in which a computer controls an input device that includes a sensor unit that detects a proximity state of an object at a plurality of positions on a detection surface, and that inputs information according to the proximity state of the object to the detection surface,
Controlling the sensor unit to perform a periodic detection operation for detecting the proximity state of the object at the plurality of positions every cycle;
Acquiring the coordinates of the position of the object close to the detection surface based on the detection result of the sensor unit for each cycle of the detection operation;
Associating the coordinates of the same object acquired in different cycles of the detection operation;
Detecting a linking error for the series of coordinates based on the series of the coordinates linked by the step of linking the coordinates over a series of cycles of the detection operation;
It possesses a step of correcting the error of the association detected in the step of detecting said error,
The step of associating the coordinates assigns the same identification code to the coordinates of the same object acquired in different cycles of the detection operation,
The step of correcting the error includes an error in associating the first coordinate acquired in one cycle of the detection operation with the second coordinate acquired in the cycle immediately before the one cycle. And determining an error in the step of detecting the error, an identification code different from the second coordinate is assigned to the first coordinate . In the step of correcting the error, when it is determined that there is an error in associating the first coordinate with the second coordinate, the identification code in the cycle in which the first coordinate is acquired If the assigned number has reached a predetermined upper limit value, the assignment of the identification code to the first coordinate is stopped.
The input device control method according to claim 8. The step of detecting the error calculates an evaluation value according to a temporal change in the position of the object close to the detection surface, based on the series of coordinates linked by the step of linking the coordinates. The input device control method according to claim 8 or 9, wherein, when the calculated evaluation value satisfies a predetermined error determination condition, it is determined that there is an error in associating the series of coordinates. The step of detecting the error calculates at least one of an evaluation value according to a speed of an object close to the detection surface and an evaluation value according to an acceleration of the object. Control method of input device. The step of detecting the error includes a first coordinate acquired in one cycle of the detection operation, a cycle acquired immediately before the one cycle, and linked to the first coordinate. An evaluation value corresponding to the acceleration is calculated based on the second coordinate and the third coordinate acquired in the cycle two before the one cycle and linked to the second coordinate. The method of controlling an input device according to claim 11. The step of detecting the error includes a first coordinate acquired in one cycle of the detection operation, a cycle acquired immediately before the one cycle, and linked to the first coordinate. The control method for the input device according to claim 11, wherein an evaluation value corresponding to the speed is calculated based on the second coordinates. The step of detecting the error determines that there is an error in associating the first coordinate with the second coordinate when the evaluation value satisfies a predetermined error determination condition. Item 14. A method for controlling an input device according to Item 12 or 13. The program for making a computer perform the control method of the input device as described in any one of Claims 8 thru | or 14 .