JP2016009475A - Input device and detection method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an input device capable of reducing data output quantity to a host apparatus.SOLUTION: An input device includes: a first electrode pattern; a second electrode pattern which intersects the first electrode pattern; and a control part which detects a plurality of signal levels corresponding to electrostatic capacity on at least one electrode pattern of the first electrode pattern and the second electrode pattern, determines inclination of distribution of the plurality of signal levels on the basis of the plurality of signal levels, and outputs the inclination to a host apparatus.

Description

  The present invention relates to an input device and a detection method. Specifically, the present invention relates to an input device and a detection method for detecting a position based on a capacitance between an operating body and an electrode.

  Conventionally, touch panel controllers output coordinate data at the time of touch or hover to the host device side. However, it is difficult for the host device to determine whether the operator is trying to touch or the menu is opened by a hover operation, and there are cases where the operation differs from the operator's intention.

  Therefore, as a technology to avoid such an erroneous operation, the palm of the hand is brought close to the operation surface when opening the menu, and the operation method is determined by touching the operation surface with a finger when performing a touch operation. It has been proposed to output raw data having a sensitivity level from a controller to an upper host device, analyze the raw data on the host device side, and determine the size of the operating body.

  For example, in Patent Document 1, a digital unit 20 as a controller of a digitizer system 100 calculates the position of a physical object such as a stylus and / or a finger that contacts a digitizer sensor, and sends it to a host computer via an interface 24. It is described. It is also described that the digital unit 20 calculates the position of the object to be hovered and sends it to the host computer via the interface 24.

JP-T 2009-543246 (see paragraphs [0088], [0089], [0092])

  However, the above-described method has a problem in that the amount of data output from the controller to the host device side increases, and the scanning speed becomes slow, or the host side is burdened with data analysis.

  Further, in the conventional technique, when the hover operation is performed on the operation surface or the operation surface is touched with a palm or the like, an accurate x is obtained because the area of the palm is larger than that of a fingertip or the like. Since it is difficult to calculate the y coordinate and the accuracy is low, it is not practical to detect the accurate coordinate in such a case. On the other hand, there is an increasing demand for detecting the approximate position of the operating body on the operating surface without requiring the accuracy of specifying the coordinates. This is because, for example, if an approximate position such as a palm is known, processing based on various events such as “the palm has moved from left to right” or “still at the top” becomes possible.

  Accordingly, an object of the present invention is to provide an input device and a detection method capable of reducing the amount of data output to the host device and detecting the approximate position of the operating body by simple processing. .

  In order to solve the above-mentioned problem, the first invention is the first electrode pattern, the second electrode pattern intersecting the first electrode pattern, at least one of the first electrode pattern and the second electrode pattern. One electrode pattern detects a plurality of signal levels in accordance with the capacitance, obtains a slope of the distribution of the plurality of signal levels based on the plurality of signal levels, and outputs the slope to the host device. An input device including a control unit.

  According to a second aspect of the present invention, a plurality of signal levels corresponding to the capacitance are detected by at least one electrode pattern of the first electrode pattern and the second electrode pattern intersecting the first electrode pattern. This is a detection method including obtaining the slope of the distribution of the plurality of signal levels based on the signal level and outputting the slope to the host device.

  As described above, according to the present invention, since the slope of the distribution of a plurality of signal levels is output to the host device, the amount of data output to the host device can be reduced, and the distribution of the distribution of the plurality of signal levels can be reduced. The approximate position of the operating body can be detected by a simple process of obtaining the inclination.

It is the schematic which shows an example of a structure of the electronic device which concerns on the 1st Embodiment of this invention. FIG. 2A is a schematic diagram illustrating a state where a palm is held over one end of the operation surface. FIG. 2B is a diagram illustrating an example of the sensitivity distribution in the state illustrated in FIG. 2A. FIG. 3A is a diagram illustrating an example of a sensitivity distribution in the x direction when a palm is held over one end of the operation surface in the x direction. FIG. 3B is a diagram illustrating an example of a sensitivity distribution in the y direction when a palm is held over one end of the operation surface in the y direction. FIG. 3C is a chart showing an example of various kinds of information in the x and y directions when a palm is held over one end of each of the operation surfaces in the x and y directions. FIG. 4A is a diagram illustrating an example of a sensitivity distribution in the x direction when a palm is held over the center of the operation surface in the x direction. FIG. 4B is a diagram illustrating an example of a sensitivity distribution in the y direction when a palm is held over the center of the operation surface in the y direction. FIG. 4C is a chart showing an example of various types of information in the x and y directions when a palm is held over the center of each of the x and y directions on the operation surface. FIG. 5A is a diagram illustrating an example of a sensitivity distribution in the x direction when a palm is held over the other end in the x direction of the operation surface. FIG. 5B is a diagram illustrating an example of a sensitivity distribution in the y direction when a palm is held over the other end of the operation surface in the y direction. FIG. 5C is a chart showing an example of various types of information in the x and y directions when a palm is held over the other end in the x and y directions of the operation surface. FIG. 6A is a diagram illustrating an example of a sensitivity distribution in the x direction when a finger is brought close to an operation surface having a small area. FIG. 6B is a diagram illustrating an example of a sensitivity distribution in the y direction when a finger is brought close to an operation surface with a small area. FIG. 6C is a chart showing an example of various types of information in the x and y directions when a finger is brought close to an operation surface with a small area. FIG. 7A is a diagram illustrating an example of a sensitivity distribution in the x direction when a palm is brought close to an operation surface having a small area. FIG. 7B is a diagram illustrating an example of a sensitivity distribution in the y direction when a palm is brought close to a small-area operation surface. FIG. 7C is a chart showing an example of various types of information in the x and y directions when a palm is brought close to a small-area operation surface. FIG. 8A is a diagram illustrating an example of a sensitivity distribution in the x direction when a finger is brought close to a large-area operation surface. FIG. 8B is a diagram illustrating an example of a sensitivity distribution in the x direction when a palm is brought close to a large-sized operation surface. It is the schematic which shows an example of a structure of a parallel plate electrode. FIG. 10A is a schematic diagram illustrating an example of a distance between a finger and an electrode. FIG. 10B is a schematic diagram illustrating an example of a distance between the palm and the electrode. FIG. 11A is a diagram illustrating an example of a reciprocal distribution of capacitance in the x direction when a finger is brought close to a small-area operation surface. FIG. 11B is a diagram illustrating an example of a reciprocal distribution of electrostatic capacitance in the y direction when a finger is brought close to a small-area operation surface. FIG. 11C is a chart showing an example of various types of information in the x and y directions when a finger is brought close to a small area operation surface. FIG. 12A is a diagram illustrating an example of the distribution of the reciprocal of the electrostatic capacitance in the x direction when the palm is brought close to a small-area operation surface. FIG. 12B is a diagram illustrating an example of the reciprocal distribution of the electrostatic capacitance in the y direction when the palm is brought close to the operation surface having a small area. FIG. 12C is a chart showing an example of various types of information in the x and y directions when the palm is brought close to a small-area operation surface. FIG. 13A is a diagram illustrating an example of a reciprocal distribution of capacitance in the x direction when a finger is brought close to a large-area operation surface. FIG. 13B is a diagram illustrating an example of a reciprocal distribution of capacitance in the x direction when a palm is brought close to a large-area operation surface. It is a block diagram which shows an example of a structure of the input device which concerns on the 4th Embodiment of this invention. It is a block diagram which shows an example of a structure of the equivalent circuit of an input device.

Embodiments of the present invention will be described in the following order with reference to the drawings. In all the drawings of the following embodiments, the same or corresponding parts are denoted by the same reference numerals.
1. First embodiment (an example of an input device that detects an approximate position of an operating tool)
2. Second Embodiment (First Example of Input Device for Detecting Size Information of Operating Body)
3. Third Embodiment (Second Example of Input Device for Detecting Size Information of Operating Body)
4). Fourth embodiment (an example of an input device capable of accurately detecting an input operation position)

<1. First Embodiment>
[Configuration of electronic equipment]
FIG. 1 shows an example of the configuration of an electronic device 10 according to the first embodiment of the present invention. The electronic device 10 is an electronic device having a touch panel function, and includes an input device 11, a display device 12, and a host device 13, as shown in FIG. The input device 11 includes a sensor unit 21 and a controller 22. The input device 11 and the display device 12 are integrated. The host device 13 may have a configuration integrated with the input device 11 and the display device 12, or may be provided separately from the integrated input device 11 and display device 12.

(Input device)
The input device 11 is a capacitive touch panel such as a projected capacitive touch panel that has a proximity detection function or a hover function of an operating tool. The input device 11 includes a sensor unit 21 and a controller 22. The sensor unit 21 has a rectangular operation surface 21s, and is provided on the display surface of the display device 12 so that the operation surface 21s is on the upper side. Here, the short direction of the rectangular operation surface 21s is defined as the x direction and the long direction is defined as the y direction.

  In addition to the touch operation, the input device 11 can also detect a touchless operation such as a hover operation. The touch operation is an operation executed by directly touching the operation surface 21s with the operation body. The touchless operation does not directly touch the operation surface 21s with the operation body, and the operation body is separated from the operation surface 21s by a predetermined interval. This operation is executed in the Examples of the operating body include a finger, a palm, and a stylus, but are not limited thereto.

  The sensor unit 21 includes an X electrode pattern (first electrode pattern) 31 and a Y electrode pattern (second electrode pattern) 32 below the operation surface 21s. Further, an FPC (Flexible Printed Circuit) 33 is provided on the periphery of the sensor unit 21.

The X and Y electrode patterns 31 and 32 are arranged in an orthogonal manner, that is, in a matrix. The X electrode pattern 31 has a plurality of X electrodes (first electrodes) X ₀ , X ₁ ,..., X _M (M: an integer greater than or equal to 1) arranged in the x direction arranged in the x direction. The adjacent X electrodes X _J-1 and X _J are separated by a predetermined distance. The Y electrode pattern 32 is configured by arranging a plurality of Y electrodes (second electrodes) Y ₀ , Y ₁ ,..., Y _N (N: an integer of 1 or more) extending in the x direction in the y direction. It is constituted by, between adjacent Y electrodes X _K-1, X _K are isolated for a predetermined. X, Y electrodes X ₀ , X ₁ ,..., X _M , Y ₀ , Y ₁ ,..., Y _N may be linear or a shape in which a plurality of rhombuses are connected in one direction. However, it is not particularly limited to these shapes.

X electrodes _{X 0,} X 1, · · ·, each of the one end of the _{X M,} extraction electrode 31a are electrically connected, these lead-out electrode 31a is electrically connected to the FPC 33. Also, Y electrode _{Y 0,} Y 1, · · ·, each of the one end of the _{Y N,} extraction electrode 32a are electrically connected, these lead-out electrode 32a is electrically connected to the FPC 33. The FPC 33 is electrically connected to the controller 22.

Operating body X, Y electrodes _X J, approaches the _{Y K,} operating tool and the X, Y electrodes _X J, capacitive coupling between the _{Y K} occurs. Operating body X, Y electrodes _X J, toward the _{Y K,} operating tool and the X, Y electrodes _X J, the capacitance between the _{Y K} increases. The controller 22 detects a plurality of sensitivity levels (signal levels) corresponding to the capacitance between the operating body and the X and Y electrodes X _J and Y _K , that is, sensitivity distribution, and the operating body is based on these sensitivity distributions. In addition to the coordinates and the number of touches, tilt and operating body size information are calculated and output to the host device 13. Note that the tilt and size information is, for example, tilt and size information when the operating tool is brought close to the operation surface 21s.

  Here, the coordinates of the operating tool include a coordinate position in the x direction obtained from the sensitivity distribution in the x direction and a coordinate position in the y direction obtained from the sensitivity distribution in the y direction. The number of touches includes the number of touches in the x direction obtained from the sensitivity distribution in the x direction and the number of touches in the y direction obtained from the sensitivity distribution in the y direction. The slope includes a numerical value related to the x direction obtained from the sensitivity distribution in the x direction and a numerical value related to the y direction obtained from the sensitivity distribution in the y direction. The inclination may be only a numerical value related to either the x direction or the y direction. The size information includes a numerical value corresponding to the size of the operating body in the x direction obtained from the sensitivity distribution in the x direction and a numerical value corresponding to the size of the operating body in the y direction determined from the sensitivity distribution in the y direction. The size information may include the size of the operating body in the x direction obtained from the sensitivity distribution in the x direction and the size of the operating body in the y direction obtained from the sensitivity distribution in the y direction.

The controller 22, based on the measurement algorithm predetermined capacitance, operating tool and the X, Y electrodes _{X 0, X 1, ···,} X M, Y 0, Y 1, ···, Y N with the respective Detect the capacitance between. As a measurement algorithm, for example, a Relaxation Oscillator method, a Charge Transfer method, or the like can be used, but is not limited thereto.

  The controller 22 may have the same resolution as the arrangement pitch of the X and Y electrode patterns 31 and 32, but the resolution is finer than the arrangement pitch of the X and Y electrode patterns 31 and 32, for example, the arrangement pitch. It is preferable to have a resolution that is several times finer.

(Display device)
As the display device 12, for example, a liquid crystal display, an electroluminescence (EL) display, a CRT (Cathode Ray Tube) display, a plasma display (Plasma Display Panel: PDP), or the like can be used. The display device 12 displays various screens such as a menu screen based on the control of the host device 13.

(Host device)
The host device 13 is a main body of the electronic device 10. Examples of the electronic device 10 include, but are not limited to, a mobile phone (for example, a smart phone) such as a personal computer and a smartphone, a tablet computer, a television, a camera, a portable game device, a car navigation system, and a wearable device. is not. The host device 13 may be an electronic device independently.

  The host device 13 controls the screen display of the display device 12 based on the coordinates of the operating body supplied from the input device 11 or the approximate position, the number of touches, and size information.

  Hereinafter, it will be described with reference to FIGS. 2 to 6 that the input device 11 detects an approximate position of an operating body such as a palm by a simple process. If an approximate position such as a palm is known on the host device 13 side, processing by various events such as “the palm has moved from left to right” or “still at the top” becomes possible.

[Overview]
When the palm 52 is held over the left end of the operation surface 21s of the sensor unit 21 as shown in FIG. 2A, the sensitivity distribution in the x direction becomes higher at the left end as shown in FIG. 2B. In this case the most left end of the sensitivity level of the X electrodes X ₀ and Lx _0, when the sensitivity levels of the X electrodes X _W spaced a predetermined distance W from the left end and Lx _w, the slope of the sensitivity distribution in the x-direction in the left vicinity (average gradient ) Kx is
_{kx = (Lx w -Lx 0)} / W ··· (1)
It can be asked. Further, if the predetermined interval W is a fixed value, the slope kx of the sensitivity distribution in the x direction near the left end is simply
kx = Lx _w −Lx ₀ (2)
Can be expressed as

When held over the palm 52 at the right end of the likewise operation surface 21s, the right end of the X electrodes _{X M} sensitivity level Lx _M of the sensitivity level of the X electrodes _{X M-W} spaced a predetermined distance W from the right and _{Lx M-W} Then, the slope kx of the sensitivity distribution in the x direction near the right end is
_{kx = Lx M -Lx M-W} ··· (3)
Can be expressed as

  When the palm 52 is near the center of the left and right, the left end inclination kx is “plus” and the right end inclination kx is “minus”. Therefore, at this time, the slope kx is defined as “zero”.

  According to such calculation, when the palm 52 is at the left end of the sensor unit 21, the inclination kx is “minus”, and when the palm 52 is at the center of the sensor unit 21, the inclination kx is “zero”. When the palm 52 is at the right end of the sensor unit 21, the inclination kx is “plus”.

The same calculation is performed for the y direction. That is, if the sensitivity level of the Y electrode Y _{0 at} the upper end is L _Y0, and the sensitivity level of the Y electrode Y _{W that} is a predetermined distance W away from the upper end is L _YW , the slope of the sensitivity distribution in the y direction in the vicinity of the left end (average slope) Ky is
ky = Ly _w -Ly ₀ (4)
Can be expressed as

When held over the palm 52 similarly to the lower end of the sensor unit 21, the sensitivity level _{L YN} of the lower end of the Y electrodes _{Y N,} the sensitivity level of the Y electrode _{Y M-W} spaced a predetermined distance W from the lower end _{L YM-W} Then, the slope ky of the sensitivity distribution in the y direction near the lower end is
ky = Ly _M -Ly _M-W (5)
Can be expressed as

  When the palm 52 is at the upper end of the sensor unit 21, the tilt ky is “minus”, and when the palm 52 is at the center of the sensor unit 21, the tilt ky is “zero” and the palm 52 is When it is at the lower end, the inclination ky is “plus”.

  Therefore, the controller 22 obtains the above-described inclinations kx and ky and sends them to the host device 13 side, whereby the approximate position of the palm 52 can be detected on the host device 13 side.

[Operation of input device]
<< Slope of sensitivity distribution in x direction >>
When an operating body such as a palm is brought close to the operation surface 21s, the controller 22 calculates the inclination kx in the x direction as follows. First, the controller 22 sequentially scans the X electrodes X ₀ , X ₁ ,..., X _M to acquire the sensitivity distribution of the sensor unit 21 in the x direction.

  Next, the controller 22 calculates an inclination kx at each of different positions in the x direction from the acquired sensitivity distribution in the x direction. For example, the inclination kx is calculated at each of the left end, the center, and the right end of the operation surface 21s. The operation surface 21s may be divided into n in the x direction (n: an integer of 3 or more), and the slope kx may be calculated at each boundary position of each divided region. In addition, the inclination kx may be calculated at the positions of the left end and the right end of the operation surface 21s and the boundary position of each divided region obtained by dividing the operation surface 21s into m directions (m: an integer of 2 or more). Next, the controller 22 outputs the calculated plurality of inclinations kx to the host device 13.

<< Slope of sensitivity distribution in y direction >>
When an operating body such as a palm is brought close to the operation surface 21s, the controller 22 calculates the inclination in the y direction as follows. First, the controller 22 sequentially scans the Y electrodes Y ₀ , Y ₁ ,..., Y _M to acquire the sensitivity distribution of the sensor unit 21 in the y direction.

  Next, the controller 22 calculates the inclination ky at each of different positions in the y direction from the acquired sensitivity distribution in the y direction. For example, the inclination ky is calculated at each of the upper end, the center, and the lower end of the operation surface 21s. The operation surface 21s may be divided into n parts in the y direction (n: an integer of 3 or more), and the slope ky may be calculated at each boundary position of each divided region. Alternatively, the inclination ky may be calculated at the positions of the upper end and the lower end of the operation surface 21s and the boundary position of each divided region obtained by dividing the operation surface 21s into m directions (m: integer of 2 or more). Next, the controller 22 outputs the calculated plurality of inclinations ky to the host device 13.

  FIGS. 3A and 3B show examples of sensitivity distributions in the x and y directions when the palm is brought close to the center of the left end of the operation surface 21s as the operation body. 4A and 4B show examples of sensitivity distributions in the x and y directions when the palm is brought close to the center of the operation surface 21s as the operation body. 5A and 5B show examples of sensitivity distributions in the x and y directions when the palm is brought close to the center of the right end of the operation surface 21s as the operation body. Here, when the slopes kx and ky of the sensitivity distribution in the x and y directions are expressed by 0 to 255, and the palm is located at the center of the operation surface 21s, the slopes kx and ky of the sensitivity distribution in the x and y directions are 128. The tilt data is offset and displayed so that

  FIG. 3C shows coordinates, inclination, size information, and the number of touches obtained by the above-described calculation method from the sensitivity distribution shown in FIGS. 3A and 3B. FIG. 4C shows coordinates, inclination, size information, and the number of touches obtained by the above-described calculation method from the sensitivity distribution shown in FIGS. 4A and 4B. FIG. 5C shows coordinates, inclination, size information, and the number of touches obtained by the above-described calculation method from the sensitivity distribution shown in FIGS. 5A and 5B.

  The host device 13 can detect the approximate position of the operating tool based on a plurality of inclinations kx and ky supplied from the controller 22. For example, the approximate position of the operating body can be detected by determining whether kx and ky are “plus”, “zero”, and “minus”, respectively. For example, when both kx and ky are “plus”, it can be detected that the operating body is in the vicinity of the upper left end of the operating surface 21s.

[effect]
In the input device 11 according to the first embodiment, by outputting the approximate position of the operating body, on the host device 13 side, for example, an operating body such as a palm from any of the upper, lower, left and right directions with respect to the operating surface 21s. It is possible to determine whether the object is approaching or to determine the direction in which the palm is shaken diagonally left, right, up, down, and so on. It is also possible to prevent malfunctions that are not intended by the operator.

  In the first embodiment described above, the configuration in which the FPC 33 and the controller 22 are separately provided has been described as an example. However, the controller 22 may be mounted on the FPC 33. That is, a COF (Chip On FPC) configuration may be employed.

  In the above-described embodiment, the configuration in which the input device 11 is provided on the display surface of the display device 12 has been described as an example. However, the input device 11 may be provided in the display device 12.

<2. Second Embodiment>
In the first embodiment, the example in which the approximate position of the operating tool is detected by obtaining the slope of the distribution of a plurality of signal levels and outputting the slope has been described. In the electronic device 10, in addition to the approximate position of the operating tool, the size information of the operating tool may be useful. Hereinafter, an input device 11 according to a second embodiment of the present invention that can output size information of an operating tool will be described with reference to FIGS. 6 to 8. The configuration of the input device 11 according to the second embodiment is the same as that shown in FIG.
[Operation of input device]
As a method for calculating the size information in the controller 22, it is preferable to select and use a suitable one according to the area of the operation surface 21s of the sensor unit 21. Hereinafter, the operation of the input device 11 will be described separately for a case where the area of the operation surface 21s is a small area and a case where the area of the operation surface 21s is a large area.

  Here, the small area means an area equivalent to or smaller than the size of an operating body (for example, a palm) for detecting the size. Moreover, a large area means an area larger than the size of an operating body (for example, a palm) for the purpose of size detection.

(Small area operation surface)
<< Size information in x direction >>
When the operating tool is brought close to the small-area operating surface 21s, the controller 22 calculates the size information Sx in the x direction as follows. First, the controller 22 sequentially scans the X electrodes X ₀ , X ₁ ,..., X _M to acquire the sensitivity distribution of the sensor unit 21 in the x direction. Here, the sensitivity distribution is a distribution of capacitance or a distribution of values proportional to the capacitance. FIG. 6A shows an example of the sensitivity distribution in the x direction when a finger is brought close to the center of the operation surface having a small area as an operation body. FIG. 7A shows an example of a sensitivity distribution in the x direction when a palm is brought close to an operation surface having a small area as an operation body.

Next, the controller 22 determines, from the acquired sensitivity distribution in the x direction, a sensitivity level Lx _{p at} which the sensitivity distribution in the x direction has a maximum value (peak value), and both ends of the sensitivity distribution in the x direction (that is, the operation surface in the x direction). The size information Sx of the operating body in the x direction is calculated using the sensitivity levels Lx ₀ and Lx _{m in} the vicinity of both ends of 21 s). Specifically, the size information Sx of the operating tool in the x direction is calculated using the following equation (6a).
Sx = ((Lx ₀ + Lx _m ) / Lx _p ) × 100 (6a)

<< Size information in y direction >>
When the operating tool is brought close to the small-area operating surface 21s, the controller 22 calculates the size information Sy in the y direction as follows. First, the controller 22 sequentially scans the Y electrodes Y ₀ , Y ₁ ,..., Y _N to acquire the sensitivity distribution of the sensor unit 21 in the y direction. FIG. 6B shows an example of the sensitivity distribution in the y direction when a finger is brought close to the center of the small area operation surface 21s as an operation body. FIG. 7B shows an example of the sensitivity distribution in the y direction when the palm of the hand is brought close to the small area operation surface 21s.

Next, the controller 22 determines, from the acquired sensitivity distribution in the y direction, the sensitivity level Ly _{p at} which the sensitivity distribution in the y direction has a maximum value (peak value), and both ends of the sensitivity distribution in the y direction (that is, the operation surface in the y direction). The size information of the operating body in the y direction is calculated using the sensitivity levels Ly ₀ and Ly _{n in} the vicinity of both ends of 21 s). Specifically, the size information Sy of the operating tool in the y direction is calculated using the following equation (6b).
_{Sy = ((Ly 0 + Ly} n) / Ly p) × 100 ··· (6b)

  Expressions (6a) and (6b) are also the flatness of the sensitivity level, which does not exceed 200 at the maximum, and the value becomes smaller as the operating body becomes smaller. When the width of the operation surface 21s in the y direction is narrower than the width of the operation surface 21s in the x direction, the size information Sy tends to be larger than the size information Sx. Conversely, when the width of the operation surface 21s in the y direction is wider than the width of the operation surface 21s in the x direction, the size information Sy tends to be smaller than the size information Sx.

  The controller 22 also calculates the coordinates of the operating tool and the number of touches in the x and y directions, in addition to the size information of the operating tool in the x and y directions, from the sensitivity distributions acquired in the x and y directions as described above. To do. Specifically, the controller 22 calculates the position of the maximum point of the sensitivity distribution in the x and y directions as the position of the operating body in the x and y directions, respectively. In addition, the controller 22 calculates, as the number of touches, the number of maximum points that exceed a predetermined level among the maximum points of the sensitivity distribution in the x and y directions.

  FIG. 6C shows coordinates, size information, and the number of touches calculated by the above-described operation from the sensitivity distribution shown in FIGS. 6A and 6B. FIG. 7C shows coordinates, size information, and the number of touches calculated by the above-described operation from the sensitivity distribution shown in FIGS. 7A and 7B. In the charts shown in FIGS. 6C and 7C, the two coordinates are shown for each of the x and y directions so that the controller 22 can detect multi-touch (that is, a plurality of maximum values). Because.

  6C and 7C, the size information Sx, Sy in the x and y directions is greater when the finger is moved closer to the operation surface 21s as the operation body than when the palm is moved closer to the operation surface 21s as the operation body. Both are small and it can be seen that the size information of the two operating bodies is greatly different. Therefore, the host device 13 can determine which of the finger and the palm is approaching as the operating body based on the size information Sx and Sy output from the controller 22. Specifically, for example, when the size information Sx, Sy output from the controller 22 is equal to or less than a predetermined value, the host device 13 can determine that the operating body close to the operation surface 21s is a finger. On the other hand, when the size information output from the controller 22 exceeds the specified value, it can be determined that the operating body close to the operating surface 21s is a palm.

(Large area operation surface)
<< Size information in x direction >>
When the operating tool is brought close to the large-area operating surface 21s, the controller 22 calculates the size information Sx in the x direction as follows. First, the controller 22 sequentially scans the X electrodes X ₀ , X ₁ ,..., X _M to acquire the sensitivity distribution of the sensor unit 21 in the x direction. FIG. 8A shows an example of the sensitivity distribution in the x direction when a finger is brought close to the center of the large operation surface 21s as an operation body. FIG. 8B shows an example of the sensitivity distribution in the x direction when the palm is brought close to the center of the large-area operation surface 21s as the operation body.

Next, the controller 22 determines, from the acquired sensitivity distribution in the x direction, the sensitivity level Lx _{p at} which the sensitivity distribution in the x direction has a maximum value (peak value), and the position x _p from the position x _p of the sensitivity level Lx _p (X electrode). a sensitivity level Lx _a predetermined distance [Delta] x _a distant position _{x a} in the arrangement direction) of the pattern 31, the sensitivity level of the position spaced a predetermined distance [Delta] x _b in the direction opposite to the x-direction from the position _{x p} of the sensitivity level Lx _p Lx _{Using b} , the size information of the operating body in the x direction is calculated. Specifically, the size information Sx of the operating tool in the x direction is calculated using the following equation (7a).
Sx = ((Lx _a + Lx _b ) / Lx _p ) × 100 (7a)

The intervals Δx _a and Δx _b are selected so that the sum of Δx _a and Δx _b (Δx _a + Δx _b ) is approximately the same as the size of an operating body (for example, a palm) for the purpose of detecting the size information Sx. It is preferable. The intervals Δx _a and Δx _b are preferably the same value, but may be different values.

<< Size information in y direction >>
Controller 22, the sensitivity distribution of the maximum value of the y-direction and sensitivity levels Ly _p as the (peak value), the predetermined interval [Delta] y _a separation in the y-direction from the position _{y p} of the sensitivity level Ly _p (arrangement direction of the Y electrode pattern 32) calculating a sensitivity level Ly _a position, the y-direction from the position y _p of the sensitivity level Ly _p by using the sensitivity level Ly _b position spaced a predetermined distance [Delta] y _b in the opposite direction, the size information Sy in the y direction To do. Specifically, the size information Sy of the operating tool in the y direction is calculated using the following formula (7b).
Sy = ((Ly _a + Ly _b ) / Ly _p ) × 100 (7b)

The intervals Δy _a and Δy _b are selected so that the sum of Δy _a and Δy _b (Δy _a + Δy _b ) is approximately the same as the size of the operating body (for example, the palm) for detecting the size information Sy. It is preferable. The intervals Δy _a and Δy _b are preferably the same value, but may be different values.

[effect]
In the input device 11 according to the second embodiment, the controller 22 calculates not only the coordinates of the operating body of the operating body, the approximate position, and the number of touches, but also the size information of the operating body at the time of proximity, and the information is hosted. Output to the device 13. Thereby, since it is not necessary to output the raw data of the sensitivity distribution in the x and y directions from the controller 22 to the host device 13, the amount of data output to the host device 13 can be reduced.

  Further, when the controller 22 outputs the size information Sx, Sy of the operating tool to the host device 13, in addition to the approximate position of the operating tool due to the tilt described above on the host device 13, for example, a finger and You can distinguish which palm is approaching. It is also possible to prevent malfunctions that are not intended by the operator.

[Modification]
In the second embodiment described above, an example is described in which the controller 22 calculates the size information Sx and Sy of the operating tool using the sensitivity levels Lx _p and Ly _{p at} which the sensitivity distribution in the x and y directions becomes maximum values. However, the present invention is not limited to this example. For example, instead of the sensitivity levels Lx _p and Ly _{p that} are maximum values, the sensitivity level at the approximate center position of the operation surface 21s in the x and y directions may be used.

In the second embodiment described above, the controller 22 determines that the sensitivity level L _{xp at} which the sensitivity distribution in the x direction has a maximum value and the sensitivity levels Lx ₀ and Lx _m at both ends of the sensitivity distribution in the x direction or in the vicinity thereof. The example of calculating the size information Sx of the operating body using the three sensitivity levels has been described, but the present invention is not limited to this example. For example, the controller 22, the sensitivity level Lx _p sensitivity distribution in the x direction becomes the maximum value, one of the sensitivity level of the ends or sensitivity level Lx 0 in the vicinity _thereof, Lx _m of the sensitivity distribution in the x-direction The size information Sx of the operating tool may be calculated using the two sensitivity levels. Specifically, the size information Sx of the operating tool in the x direction may be calculated using one of the following formulas (8a) and (8b).
Sx = (Lx ₀ / Lx _p ) × 100 (8a)
Sx = (Lx _m / Lx _p ) × 100 (8b)

Note that the controller 22 may calculate the size information S _y of the operating tool in the y direction using two sensitivity levels in the same manner as the size information S _x of the operating tool in the x direction described above.

<3. Third Embodiment>
In the second embodiment, the example of calculating the size information Sx, Sy of the operating body using the sensitivity distribution of the sensor unit 21, that is, the distribution of values proportional to the capacitance has been described. However, the size information Sx, Sy is described. The calculation method is not limited to this example. In the third embodiment, an example in which the size information Sx, Sy of the operating tool is calculated using the inverse distribution of the capacitance will be described.

[Overview]
FIG. 9 shows an example of the configuration of parallel plate electrodes. As shown in FIG. 9, the parallel plate electrode includes plate electrodes 41, 42 arranged in parallel and spaced apart from each other by a distance d, and a dielectric 43 provided between the plate electrodes 41, 42. The capacitance C of the parallel plate electrode having such a configuration is generally represented by the following formula (9). As can be seen from this equation (9), the capacitance C is inversely proportional to the distance d.
C = ε ₀ ε (S / d) (9)
Where ε ₀ : dielectric constant in vacuum (ε ₀ = 8.854 × 10 ⁻¹² [F / m]), ε: relative dielectric constant, S: facing area [m ² ] between electrodes, d: dielectric Thickness [m]
Thus, X of the sensor unit 21, Y electrodes _{X 0, X 1, ···,} X M, Y 0, Y 1, ···, readily finger from the reciprocal of the sensitivity of _{Y N} (proportional to the capacitance) The distance to the operating body can be calculated.

For example, X electrodes _X 0, which is arranged as shown in FIG _{10A, X 1, ···, C} 0, C 1 and the capacitance between the _{X 6} and the finger 51, ..., when _{C 6,} The distances d ₀ , d ₁ ,..., D ₆ between the X electrodes X ₀ , X ₁ ,..., X ₆ and the finger are expressed by the following formula (10).
d _n = k (S / C _n ) (10)
However, n: electrode number, k: coefficient In addition, if the operation member is the palm rather than a finger, the distance _{d 0,} d 1 as shown in FIG. 10B, · · ·, the difference in _{d 6} is seen also be reduced .

Therefore, the size of the operating body can be determined from the distribution of the reciprocal of the electrostatic capacity between the X electrodes X ₀ , X ₁ ,..., X ₆ and the operating body. For example, the controller 22 compares the value _{d 0} of the electrodes _{X 0} in the smallest value, a certain distance from it to the value _{d 3} of the X electrode _{X 3} in FIG. 10A. When the difference is large, it can be determined that the operating tool is small, and when the difference is small, the operating tool is large.

[Operation of input device]
Hereinafter, the operation of the input device 11 will be described separately for a case where the area of the operation surface 21s is a small area and a case where the area of the operation surface 21s is a large area.

<Small area operation surface>
<< Size information in x direction >>
When the operating tool is brought close to the small-area operating surface 21s, the controller 22 calculates the size information Sx in the x direction as follows. First, the controller 22 sequentially scans the X electrodes X ₀ , X ₁ ,..., X _M to acquire the capacitance of the sensor unit 21 in the x direction. Further, the inverse of the electrostatic capacity or a value inversely proportional to the electrostatic capacity is obtained by calculation, thereby obtaining the distribution of the inverse of the electrostatic capacity in the X direction. FIG. 11A shows an example of the distribution of the reciprocal of the capacitance in the x direction when a finger is brought close to the center of the operation surface 21s having a small area. FIG. 12A shows an example of the distribution of the reciprocal of the electrostatic capacitance in the x direction when the palm is brought close to the center of the small area operation surface 21s as the operation body.

Next, the controller 22 determines the level (1 / Lx _p ) at which the distribution of the reciprocal of the electrostatic capacity in the x direction is a minimum value from the distribution of the reciprocal of the electrostatic capacity in the x direction and the electrostatic capacity in the x direction. Using the both ends of the distribution of the reciprocal capacity (that is, both ends of the operation surface 21s in the x direction) or levels (1 / Lx ₀ ) and (1 / Lx _m ) in the vicinity thereof, the size information of the operation body in the x direction. Sx is calculated. Specifically, the size information Sx of the operating tool in the x direction is calculated using the following formula (11a).
Sx = ((1 / Lx ₀ ) + (1 / Lx _m )) − (1 / Lx _p ) (11a)

<< Size information in y direction >>
When the operating tool is brought close to the small-area operating surface 21s, the controller 22 calculates the size information Sy in the y direction as follows. First, the controller 22 sequentially scans the Y electrodes Y ₀ , Y ₁ ,..., Y _N to obtain a reciprocal distribution of the capacitance of the sensor unit 21 in the y direction. FIG. 11B shows an example of the distribution of the reciprocal of the electrostatic capacitance in the y direction when a finger is brought close to the center of the small-area operation surface 21s as an operation body. FIG. 12B shows an example of the distribution of the reciprocal of the electrostatic capacitance in the y direction when the palm of the hand is brought close to the center of the small area operation surface 21s.

Next, the controller 22 determines the level (1 / Ly _p ) at which the distribution of the reciprocal of the electrostatic capacity in the y direction becomes a minimum value from the distribution of the reciprocal of the electrostatic capacity in the y direction and the electrostatic capacity in the y direction. level in the vicinity of both ends (i.e. both ends of the operating surface 21s in the y-direction) or their distribution of the reciprocal of capacitance ₍₁ / Ly 0), by using the (1 / Ly _n), the size information of the operating body in the y-direction Sy is calculated. Specifically, the size information S _y of the operating tool in the y direction is calculated using the following equation.
_{Sy = ((1 / Ly 0} ) + (1 / Ly n)) - (1 / Ly p) ··· (11b)

FIG. 11C shows coordinates, size information, and the number of touches obtained from the distribution of the reciprocal capacitance shown in FIGS. 11A and 11B. FIG. 12C shows coordinates, size information, and the number of touches obtained from the distribution of the reciprocal capacitance shown in FIGS. 12A and 12B. Note that the size information values described in FIGS. 11C and 12C are 1 byte length, that is, in order to represent the size information with a value in the range of 0 to 255, the necessary values are multiplied by the actual Sx and Sy values. In order to match the trend of the magnitude of this value with the magnitude of the actual size,
255-(converted value of Sx), 255-(converted value of Sy)
This is a value obtained by performing the operation.

<Large-area operation surface>
<< Size information in x direction >>
When the operating tool is brought close to the large-area operating surface 21s, the controller 22 calculates the size information Sx in the x direction as follows. First, the controller 22 sequentially scans the X electrodes X ₀ , X ₁ ,..., X _M to acquire the distribution of the reciprocal of the capacitance of the sensor unit 21 in the x direction. FIG. 13A shows an example of the distribution of the reciprocal of the electrostatic capacitance in the x direction when a finger is brought close to the center of the large operation surface 21s as an operation body. FIG. 13B shows an example of the distribution of the reciprocal of the electrostatic capacitance in the x direction when the palm of the hand is brought close to the center of the large-area operation surface 21s.

Next, the controller 22 determines the level (1 / Lx _p ) and the level (1 / Lx _p ) at which the distribution of the reciprocal of the electrostatic capacity in the x direction is minimized from the distribution of the reciprocal of the electrostatic capacity in the x direction. ) and the level of the position _{x a} spaced predetermined distance [Delta] x _a from the position xp in the x direction (arrangement direction of the X electrode pattern 31) of (1 / Lx _a), the x-direction from the position xp level (1 / Lx _p) Calculates the size information Sx of the operating body in the x direction using the level (1 / Lx _b ) at a position spaced apart by a predetermined interval Δx _b in the opposite direction. Specifically, the size information Sx of the operating tool in the x direction is calculated using the following formula (12a).
Sx = ((1 / Lx _a ) + (1 / Lx _b )) − (1 / Lx _p ) (12a)

<< Size information in y direction >>
Controller 22, the array direction of y to the direction of distribution of the reciprocal of the capacitance becomes the minimum value level (1 _{/ L yp),} level (1 _{/ L yp)} y-direction from the position _{y p} of the (Y electrode patterns 32 ) At a position (1 / L _ya ) that is _a predetermined distance Δy _a apart, and a level (1 / L y) at a position that is a predetermined distance Δy _b away from the position y _{p of the} level (1 / L _yp ) in the direction opposite to the y direction. L _yb ) is used to calculate the size information Sy in the y direction. Specifically, the size information Sy of the operating tool in the y direction is calculated using the following equation (12b).
Sy = ((1 / L _ya ) + (1 / L _yb )) − (1 / L _yp ) (12b)

[Modification]
In the above-described third embodiment, the controller 22 uses the levels (1 / Lx _p ) and (1 / Ly _p ) at which the distribution of the reciprocal of the electrostatic capacity in the x and y directions is a minimum value. Although the example of calculating the size information Sx and Sy of the above has been described, the present invention is not limited to this example. For example, instead of the levels (1 / Lx _p ) and (1 / Ly _p ), the level at the substantially central position of the operation surface 21 s in the x and y directions may be used.

Further, in the third embodiment described above, the controller 22 determines the level (1 / Lx _p ) at which the distribution of the reciprocal of the electrostatic capacitance in the x direction becomes a minimum value and the distribution of the reciprocal of the electrostatic capacitance in the x direction. The example in which the size information Sx of the operating body is calculated using the three levels of the levels (1 / Lx ₀ ) and (1 / Lx _m ) at both ends or in the vicinity thereof has been described. It is not limited. For example, the controller 22 has a level (1 / Lx _p ) at which the distribution of the reciprocal of the electrostatic capacitance in the x direction becomes a minimum value, and a level (1) at both ends of the distribution of the reciprocal of the electrostatic capacity in the x direction. The size information Sx of the operating tool may be calculated by using two levels of either one of / Lx ₀ ) and (1 / Lx _m ). Specifically, the size information S _x of the operating tool in the x direction may be calculated using one of the following formulas (13a) and (13b).
Sx = (1 / Lx ₀ ) − (1 / Lx _p ) (13a)
Sx = (1 / Lx _m ) − (1 / Lx _p ) (13b)

  Note that the controller 22 may calculate the size information Sy of the operating tool in the y direction using two levels in the same manner as the size information Sx of the operating tool in the x direction described above.

<4. Fourth Embodiment>
Hereinafter, an input device 101 according to a fourth embodiment of the present invention will be described with reference to FIGS. 14 and 15. As shown in FIG. 14, the input device 101 has the main circuit components constituting the input device 101 mounted on two types of non-vibration side circuit boards 102 and vibration side circuit boards 103.

  The non-vibration circuit board 102 is wired with a reference power supply circuit 104 including a low-voltage reference power supply line GND and a high-voltage reference power supply line VCC, which are set to the ground potential, and a DC voltage Vcc between the low-voltage reference power supply line GND and the high-voltage reference power supply line VCC. Is connected to a DC power source 105. Thereby, each circuit component such as the interface circuit 106 mounted on the non-vibration circuit board 102 is connected to the reference power supply circuit 104 and driven by the output voltage Vcc of the DC power supply 105.

  Further, the vibration side circuit board 103 is provided with a vibration power supply circuit 107 including a low voltage vibration power supply line SGND and a high voltage vibration power supply line SVCC. The low-voltage vibration power supply line SGND is connected to the low-voltage reference power supply line GND, and the high-voltage vibration power supply line SVCC is connected to the high-voltage reference power supply line VCC via coils 108 and 109, respectively. The inductances of the coil 108 and the coil 109 are both set to a value having a high impedance with respect to a natural oscillation signal SG having a natural frequency f described later. Here, the coils 108 and 109 having the same inductance L are used. As a result, as shown in FIG. 14, when the natural oscillation signal SG of the natural frequency f is synchronized and output to the low voltage reference power line GND and the high voltage reference power line VCC of the reference power circuit 104, the low voltage reference of the reference power circuit 104 is output. Since the power supply line GND is grounded and at a stable potential, the potentials of the low-voltage vibration power supply line SGND and the high-voltage vibration power supply line SVCC of the vibration power supply circuit 107 fluctuate synchronously with the natural frequency f. The DC output voltage Vcc is the same as that of the reference power supply circuit 104.

On the vibration side circuit board 103 to which the vibration power supply circuit 107 is wired, a number of X, Y electrodes X ₀ , X ₁ ,..., X _M , Y ₀ , Y ₁ ,. _N is connected to either the low-voltage vibration power supply line SGND or the high-voltage vibration power supply line SVCC of the vibration power supply circuit 107, here the high-voltage vibration power supply line SVCC. Numerous X, Y electrodes _{X 0, X 1, ···,} X M, Y 0, Y 1, ···, Y N is the separately provided insulating panel and the vibration-side circuit board 103 or the vibration-side circuit board 103 When the operator performs an input operation with the finger as the input operation body directed toward the input operation surface along the surface to be the input operation surface, the X and Y electrodes X ₀ , X ₁ ,. .., X _M , Y ₀ , Y ₁ ,..., Y _N are arranged on the entire input operation surface so as to face or approach the fingers.

When all the X and Y electrodes X ₀ , X ₁ ,..., X _M , Y ₀ , Y ₁ ,..., Y _N are connected to the high-voltage vibration power supply line SVCC, the potential becomes the natural frequency f. Since the potential of the finger of the operator whose part such as the foot is grounded while being vibrated is a constant potential, the X, Y electrodes X ₀ , X where the finger approaches and the capacitance Cf with the finger increases. _{1, ···, X M, Y} 0, Y 1, ···, the _{Y N,} X, _Y electrodes _{X 0, X 1, ···,} X M, Y 0, Y 1, ···, voltage signal of natural frequency f is output via the electrostatic capacitance Cf from Y _N to the finger. If this is viewed from the vibration power supply circuit 107 that vibrates at the natural frequency f, the X, Y electrodes X ₀ , X ₁ ,..., X _M , Y ₀ , Y ₁ ,. , it is assumed that the potential of the Y _N vibrates at a relatively natural frequency f, the input operation detection means for driving a vibration source circuit 107, the potential variation signal of natural frequency f, i.e. to detect a specific oscillation signal, inherent oscillation signal X but detected, Y electrodes _{X 0, X 1, ···,} X M, Y 0, Y 1, ···, can detect an input operation from the _{Y N.}

  In order to detect the input operation in this manner, the vibration side circuit board 103 further includes circuits of an analog multiplexer 112, a band pass filter 113, an A / D converter 114, an MPU (microprocessor unit) 10, and an oscillation circuit 115. The elements are mounted, and both are connected to the low-voltage vibration power supply line SGND and the high-voltage vibration power supply line SVCC of the vibration power supply circuit 107 and operate by receiving the output voltage Vcc from the DC power supply 105.

All X, Y electrodes X ₀ , X ₁ ,..., X _M , Y ₀ , Y ₁ ,..., Y _N are connected to the input of the analog multiplexer 112, and the analog multiplexer 112 is connected to the MPU 110. the switching control, all X at a constant scanning cycle, Y electrodes _{X 0, X 1, ···,} X M, Y 0, Y 1, ···, a _{Y N} every one pattern, not shown amplifier circuit To the band-pass filter 113.

  The band pass filter 113 passes a signal in a frequency band centered on the natural frequency f of the natural oscillation signal. The band pass filter 113 cuts low frequency components such as a DC signal and high frequency noise such as common mode noise. Then, only the natural oscillation signal SG is output to the A / D converter 114 at the subsequent stage.

The A / D converter 114 samples at a frequency that is at least twice the natural frequency f of the natural oscillation signal SG, quantizes the level of the natural oscillation signal SG, and outputs the quantized signal to the MPU 110.

The quantized data output from the A / D converter 114 is the X and Y electrodes X ₀ , X ₁ ,..., X _M , Y ₀ , Y ₁ ,. Since it represents the detection level of the natural oscillation signal SG of Y _N , the MPU 110 acting as input operation detection means for detecting the input operation has its X, Y electrodes X ₀ , X ₁ ,..., X _M , Y ₀ , The sum of the quantized data input from the A / D converter 114 during the connection period of Y ₁ ,..., Y _N is compared with a predetermined threshold, and the natural oscillation signal SG is detected when the total is equal to or higher than the predetermined threshold. and the determined ones and, and that there is an input operation, the X, Y electrodes _{X 0, X 1, ···,} X M, Y 0, Y 1 input, ..., from the arrangement position of the _{Y N} Detect the operation position. The detected input operation data such as the input operation position is output to the interface circuit 106 mounted on the non-vibration circuit board 102 via the signal line 116 in which the direct current is insulated, and the interface circuit 106 performs USB communication and I ² C. It is output to a host device that uses input operation data in communication or the like.

  The oscillation circuit 115 oscillates and outputs the clock CK having the fixed frequency fck to the analog multiplexer 112, the band pass filter 113, the A / D converter 114, and the MPU 110, and synchronizes the series of operations described above by these circuits.

  The MPU 110 also functions as a signal output circuit that outputs the natural frequency f of the natural oscillation signal SG to the low-voltage reference power supply line GND and the high-voltage reference power supply line VCC of the reference power supply circuit 104. The natural frequency f of the natural oscillation signal SG is The frequency fck of the clock CK input from the oscillation circuit 115 is divided or doubled, and the amplitude is arbitrarily adjusted by stepping up or stepping down the voltage Vcc between the low-voltage vibration power supply line SGND and the high-voltage vibration power supply line SVCC. Here, a natural oscillation signal SG having a natural oscillation frequency of 187 kHz and an amplitude (voltage Vp-p between peaks) of 5 V is output. The reason why the natural frequency f is set to 187 kHz will be described later.

  The output of the MPU 110 that outputs the natural oscillation signal SG is bifurcated and connected to the low-voltage reference power line GND and the high-voltage reference power line VCC of the reference power circuit 104 through capacitors 117 and 118, respectively. Since the capacitor 117 and the capacitor 118 are interposed for the purpose of cutting off the DC voltage of the power supply line, the respective capacitances are arbitrary, but here, the capacitors 117 and 118 having the same capacitance C are used.

  When the natural oscillation signal SG having the natural frequency f flows in the reference power supply circuit 104 and the vibration power supply circuit 107, the low voltage reference power supply line GND and the high voltage reference power supply line VCC and the low voltage vibration power supply line SGGND and the high voltage vibration power supply line SVCC are close to each other. If the power supply lines are short-circuited in the band of the natural frequency f, the reference power supply circuit 104 and the vibration power supply circuit 107 in FIG. 14 are shown in the equivalent circuit diagram of FIG.

As shown in FIG. 15, since capacitors 117 and 118 having a capacitance C are connected in parallel between the output of the MPU 110 and the reference power supply circuit 104, the combined capacitance is 2C. And the combined inductance of the coils 108 and 109 connected in parallel between the vibration power supply circuit 107 is L / 2. These capacitors and inductors are connected in series in a closed circuit through which the natural oscillation signal SG having the natural frequency f flows. The amplitude (level) of the natural oscillation signal SG is Vi, the reference power supply circuit 104 at both ends of the coils 108 and 109, and the vibration power supply. If the voltage between the circuits 107 is Vo, and the angular velocity represented by 2πf is ω (rad / sec),
Vo = [ω ² LC / (ω ² LC-1)] Vi (14)
It is represented by
Here, the circuit shown in FIG. 15 resonates in series at ω ² LC = 1, and the frequency f _{0 at} that time is
f ₀ = 1 / [2π (LC) 1/2] (15)
It becomes.

That is, if the resonance frequency f ₀ obtained from the relationship of the equation (2) is the natural frequency f of the natural oscillation signal SG, the level of the natural oscillation signal SG is theoretically calculated from the equation (1) of the vibration power supply circuit 107. potential oscillates at infinity, X is connected to the oscillating power supply circuit 107, Y electrodes _{X 0, X 1, ···,} X M, Y 0, Y 1, ···, the potential of the _{Y N} to infinity Can be vibrated. As a result, X, Y electrodes _{X 0, X 1, ···,} X M, Y 0, Y 1, ···, also the capacitance between the _{Y N} and the finger is a small as approximately 10 pF, X , Y electrodes X ₀ , X ₁ ,..., X _M , Y ₀ , Y ₁ ,..., Y _N and the voltage generated between the fingers are expanded infinitely, so that they are input to the MPU 110 at the natural frequency f. The level of the natural oscillation signal SG to be increased increases and can be easily detected by the MPU 110.

The actual input device 101 does not resonate at the frequency f0 obtained from the equation (2) due to the influence of inductance, stray capacitance, etc. of the reference power supply circuit 104 and the vibration power supply circuit 107, and the reference power supply circuit 104 and the vibration power supply circuit 107. Due to the energy loss or the like when the natural oscillation signal SG flows in the oscillation power supply circuit 107, the potential oscillates with the amplitude expanded to a finite magnification with respect to the level of the natural oscillation signal SG. Meanwhile, X which may be touched by a finger of the operator, Y electrodes _{X 0, X 1, ···,} X M, Y 0, Y 1, ···, it is not possible to apply a large voltage to the _{Y N,} By shifting the natural frequency f of the natural oscillation signal SG around the resonance frequency f0 or adjusting the amplitude of the natural oscillation signal SG, the XU and Y electrodes X ₀ and X ₁ can be detected within a range where the MPU 110 can reliably detect the input operation. _{, ···, X M, Y 0} , Y 1, ···, limits the amplitude of the voltage oscillation of the _{Y N.}

As described above, the MPU 110 can easily adjust the amplitude and the natural frequency f of the natural oscillation signal SG that varies depending on the use environment and circuit constants such as the coils 108 and 109 and the capacitors 117 and 118. The natural frequency f can be an arbitrary frequency. However, around the commercial AC power supply line, the input operation body is not a constant potential, and common mode noise of the frequency of the commercial AC power supply may be superimposed. Y electrodes _{X 0, X 1, ···,} X M, Y 0, Y 1, ···, to identify the frequency of the commercial AC power from the _{Y N} is necessary to detect a specific oscillation signal SG natural frequency f Therefore, it is preferable to set the frequency excluding the frequency of the commercial AC power supply and its harmonics.

For example, in the input device 101 shown in FIG. 1, assuming that the inductances of the coils 108 and 109 are 220 μH and the capacitances of the capacitors 117 and 118 are 330 pF, the natural oscillation signal SG has an amplitude (Vp−p) of 5 V and a natural frequency f of When outputting a 187kHz from MPU 110, X for connecting the oscillating power supply circuit 107 to the vibration source circuit 107, Y electrodes _{X 0, X 1, ···,} X M, Y 0, Y 1, ···, Y N is It was actually measured to vibrate with 20 times the amplitude (Vp-p) of 20V.

In the above embodiment, a plurality of X, Y electrodes _{X 0, X 1, ···,} X M, Y 0, Y 1, ···, are arranged on the input operation surface _{Y N,} inherent oscillation signal SG X detecting a, Y electrodes _{X 0, X 1, ···,} X M, Y 0, Y 1, ···, even if the input operation position from the position of _{Y N} has been detected, a single X The touch panel may function as a capacitance switch that detects the natural oscillation signal SG from the Y electrode and detects that only an input operation has been performed.

  Further, the coil 108 and the coil 109 used in the above-described fourth embodiment do not necessarily have the same inductance, and similarly, the capacitances of the capacitor 117 and the capacitor 118 do not necessarily have to be the same.

  The oscillation circuit 115 that oscillates the clock CK is provided separately from the MPU 110. However, the oscillation circuit 115 may be built in the MPU 110. Conversely, the signal output circuit that also serves as the PMU 10 is connected to the oscillation power supply circuit 107. As long as it drives, you may mount in the vibration side circuit board 103 separately from MPU110.

  In addition, the input operation body has been described with a finger on which the operator performs an input operation, but may be an operation body different from the operator, such as a dedicated input pen held by the operator.

  Further, although the low-voltage reference power line GND is grounded and the reference power supply circuit 104 is set to a constant potential, the means for setting the constant potential is not limited to this method. For example, if the output of the DC power supply 105 is maintained at a constant potential. The low voltage reference power supply line GND and the high voltage reference power supply line VCC may be simply connected to the DC power supply 105.

[effect]
In the input device 101 according to the fourth embodiment, an input operation is performed by causing the potential of the detection electrode pattern on the capacitive touch panel side to vibrate at the natural frequency f and the voltage with the input operation body fluctuates at the natural frequency f. Therefore, it is not necessary to prepare a signal output circuit for outputting the natural oscillation signal having the natural frequency f on the input operation body side such as an operator. Further, since a common mode signal generated from a commercial AC power supply or the like is not used as a natural oscillation signal for detecting an input operation, the input operation can be detected without being restricted in the use environment.

  Also, the reference power supply circuit to which the DC power supply is connected and the vibration power supply circuit to which the detection electrode pattern is connected are separated without using an expensive insulating component such as an insulated DC-DC converter, and the vibration power supply circuit is independently voltageated. Can be varied.

  Even if the input operation surface is enlarged, by increasing the number of detection electrode patterns formed on the insulating panel, it is possible to detect without attenuating the level of the natural oscillation signal from the individual detection electrode patterns approached by the input operation body. .

  In addition, even if the capacitance between the input operating body and the detection electrode pattern is very small, the level of the natural oscillation signal generated in the detection electrode pattern is expanded, and the input operation is reliably detected from a small change in capacitance. it can.

  Further, it is not necessary to provide a separate oscillation circuit for generating the natural oscillation signal.

  In addition, the natural frequency f and amplitude of the natural oscillation signal adjusted according to the use environment and the circuit constants of the inductor and capacitor can be easily obtained from the microprocessor that detects the input operation.

  In the case of an input device using a so-called mutual capacitance method that outputs a predetermined detection signal from a specific detection electrode and detects a signal appearing on another detection electrode in response to the detection signal, a water droplet is formed on the input operation surface. However, according to the present embodiment, even if a water droplet comes on the input operation surface, the coordinate detection is not affected.

  As mentioned above, although embodiment of this invention was described concretely, this invention is not limited to the above-mentioned embodiment, Various deformation | transformation based on the technical idea of this invention is possible.

  For example, the configurations, methods, processes, shapes, materials, numerical values, and the like given in the above-described embodiments are merely examples, and different configurations, methods, processes, shapes, materials, numerical values, and the like are used as necessary. Also good.

  The configurations, methods, steps, shapes, materials, numerical values, and the like of the above-described embodiments can be combined with each other without departing from the gist of the present invention.

DESCRIPTION OF SYMBOLS 10 Electronic device 11 Input device 12 Display device 13 Host device 21 Sensor part 22 Controller 31 X electrode pattern 32 Y electrode pattern 33 FPC
X ₀ , X ₁ ,..., X _M X electrode Y ₀ , Y ₁ ,..., Y _N Y electrode

Claims (9)

A first electrode pattern;
A second electrode pattern intersecting the first electrode pattern;
A plurality of signal levels corresponding to capacitance is detected by at least one of the first electrode pattern and the second electrode pattern,
Based on the plurality of signal levels, obtain a slope of the distribution of the plurality of signal levels, and output the slope to the host device;
An input device comprising: The input device according to claim 1, wherein the control unit obtains size information of an operation tool based on the plurality of signal levels and outputs the size information to the host device.   3. The input according to claim 2, wherein the plurality of signal levels include a maximum or minimum signal level and a signal level at a position spaced apart from the position of the maximum or minimum signal level by a predetermined interval in the arrangement direction of the electrode pattern. apparatus.   The plurality of signal levels include a maximum or minimum signal level, a signal level at a position spaced apart from the position of the maximum or minimum signal level in the arrangement direction of the electrode pattern, and the maximum or minimum signal level. The input device according to claim 2, further comprising a signal level at a position spaced apart from the position by a predetermined interval in a direction opposite to the arrangement direction.   The input device according to claim 2, wherein the plurality of signal levels include a signal level at a substantially central position of the electrode pattern and a signal level at one end in the arrangement direction of the electrode pattern or a position near the one end.   3. The input device according to claim 2, wherein the plurality of signal levels include a signal level at a substantially central position of the electrode pattern and a signal level at a position at or near both ends of the electrode pattern.   The input device according to claim 2, wherein the plurality of signal levels are inversely proportional to capacitance.   The input device according to claim 1, wherein the inclination is an inclination corresponding to an adjacent operating body. A plurality of signal levels corresponding to the capacitance are detected by at least one of the first electrode pattern and the second electrode pattern intersecting the first electrode pattern,
Obtaining a slope of the distribution of the plurality of signal levels;
A detection method including outputting the inclination to a host device.

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