JP2012108572A - Input device for electrical device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an input device having excellent design and high arrangement flexibility and capable of reliably detecting a hand position to operate an electrical device.SOLUTION: An input device 100 for an electrical device includes a sensor part 10, a circuit part 20, and a display device 30. The sensor part 10 has capacitive sensors 1-4 placed at different positions outside the display device 30. An arithmetic processing part 25 of the circuit part 20 displays a slide bar 50 for instructing operation of the electrical device on a screen D on the basis of output from each capacitive sensor 1-4, detects a position of an operator's hand 6 to detect an operation position of a bar 51, and changes display of the slide bar 50 on the basis of the operation position. The input device outputs a signal corresponding to a display position of the bar 51 to the electrical device.

Description

  The present invention relates to an input device for an electric device for manually operating the electric device.

  2. Description of the Related Art Conventionally, a hand shaking detection method and device (see, for example, Patent Document 1 below) are known as devices that detect the motion of a hand shake and control the operation of an electrical device. This hand shake detection device emits pulsed light with different phases from the four light emitting elements, receives light reflected from the hand by the emitted light by the light receiving element, and moves and moves the hand shake based on the received light amount. Detect hand gestures including speed.

JP-A-10-148640

  However, in the hand shake detection device disclosed in Patent Document 1 described above, the hand shaking state is detected by an optical means in which reflected light obtained by reflecting light emitted from the light emitting element to the hand is received by the light receiving element. . For this reason, there are the following problems in addition to the problem that the detection range of the hand is narrowed and erroneous detection and malfunction are likely to occur.

  That is, (1) Since the optical means is arranged so that it can be seen by the operator, it may be undesirable in terms of design. In addition, (2) when applied to a display device, if the wavelength of light emitted from the screen is the same as the wavelength of light used by the optical means, there is a risk that hand gestures cannot be reliably detected.

  The present invention has been made in view of the above circumstances, and provides an input device for an electric device that has a good design, a high degree of freedom in arrangement, and can reliably detect the position of the hand and operate the electric device. The purpose is to do.

  In order to solve the above-described problems and achieve the object, an input device for an electric device according to the present invention includes a display unit that displays a slide-movable indicator for instructing an operation of the electric device, and an outside of the display unit Detecting the operation position of the indicator by detecting a plurality of capacitance sensor units provided at different positions in the sensor and a capacitance value based on the capacitance detected by the plurality of capacitance sensor units, respectively. It is characterized by comprising detection means and display control means for changing the display of the indicator based on the detected operation position.

  An input device for an electric device according to the present invention is for instructing an operation of an electric device according to capacitance values from a plurality of capacitance sensor units provided at different positions outside a display unit that displays an indicator. Since the operation position of the indicator is detected and the display of the indicator is changed based on the operation position, the design is good, the degree of freedom in arrangement is high, and the position of the hand can be reliably detected.

  You may further provide the output means which outputs an output signal to the said electric equipment according to the detected operation position of the indicator.

  The plurality of capacitance sensor units include first and second capacitance sensor units arranged on a straight line across the display unit. The plurality of capacitance sensor units include a third capacitance sensor unit provided at a position different from the first and second capacitance sensor units, for example.

  In the detection means, for example, the total sum of the capacitance values detected by the plurality of capacitance sensor units is not less than a preset threshold value, and all the capacitance values are increased. Sometimes, the indicator starts to operate.

  In addition, the detection means may be configured such that, for example, the total sum of the capacitance values detected by the plurality of capacitance sensor units falls below a preset threshold value, and all the capacitance values are reduced. When the operation is in progress, the operation of the indicator is terminated.

  In the plurality of capacitance sensor units, the surface including the main surface of at least one capacitance sensor unit and the surface including the main surface of the display unit form an obtuse angle on the front side of the display unit. The display unit may be inclined.

  In this case, the at least one capacitance sensor unit may be arranged so that an inclination angle with respect to the display means can be adjusted.

  ADVANTAGE OF THE INVENTION According to this invention, the design property is favorable, the arrangement | positioning freedom degree is high, and the input device of the electric equipment which can detect the position of a hand reliably is realizable.

1 is a diagram illustrating an overall configuration of an input device for an electrical apparatus according to a first embodiment of the present invention. It is a figure which shows the partial structure of the sensor part and circuit part of the input device. It is a figure which shows the example of installation of the electric equipment provided with the input device. It is a flowchart which shows the operation processing procedure of the electric equipment provided with the input device. It is a figure for demonstrating the display state of the indicator based on the relationship between the operation position and sensor output in the input device. It is a figure which shows the example of arrangement | positioning of the sensor part of the input device. It is a figure which shows the indicator in the input device of the electric equipment which concerns on the 2nd Embodiment of this invention. It is a figure which shows the indicator in the input device of the electric equipment which concerns on the 3rd Embodiment of this invention. It is a figure for demonstrating the display state of the indicator based on the relationship between the operation position and sensor output in the input device. It is a figure which shows the whole structure of the input device of the electric equipment which concerns on the 4th Embodiment of this invention. It is a figure which shows the electrostatic capacitance detection circuit of the input device of the electric equipment which concerns on the 5th Embodiment of this invention.

  Hereinafter, embodiments of an input device for an electric apparatus according to the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a diagram illustrating an overall configuration of an input device for an electrical apparatus according to a first embodiment of the present invention. FIG. 2 is a diagram illustrating a partial configuration of the capacitance sensor unit and the circuit unit of the input device.

  As shown in FIGS. 1 and 2, the input device 100 of the electrical apparatus according to the first embodiment includes a sensor unit 10 that detects electrostatic capacitance, and a static based on the electrostatic capacitance detected by the sensor unit 10. The circuit unit 20 for detecting a capacitance value and a display device 30 of an electric device are provided. The sensor unit 10 includes a plurality of capacitance sensors 1, 2, 3, 4 provided at different positions outside the display device 30.

  In FIG. 1, the sensor unit 10 includes, for example, electrostatic capacitance sensors 1 and 2 arranged on a straight line that crosses the display screen D of the display device 30. Capacitance sensors 3 and 4 are respectively arranged. Specifically, the capacitance sensors 1 and 2 are respectively arranged to face each other with the display screen D interposed therebetween, and the capacitance sensors 3 and 4 are arranged to face each other with the display screen D interposed therebetween.

  As shown in FIG. 2, each of the capacitance sensors 1 to 4 is configured such that a detection range exists on the detection surface (sensor surface) side. These include, for example, a sensor electrode 7 formed in a rectangular flat plate shape, a shield electrode 8 formed in a rectangular flat plate shape on the back side of the sensor electrode 7, and a sensor electrode 7 formed on the same plane as the sensor electrode 7. And a shield electrode 9 formed in an enclosing square shape.

  The sensor electrode 7 of each of the capacitance sensors 1 to 4 detects a hand (or a finger or a human body, the same applies hereinafter) that falls within the detection range on the detection surface side. The shield electrode 8 shields the sensor electrode 7 from being detected on the back side. The shield electrode 9 defines a detection range around the main surface of the sensor electrode 7. These shield electrodes 8 and 9 may be connected to, for example, a shield drive circuit 26 that drives them to the same potential as the sensor electrode 7.

  On the other hand, the circuit unit 20 is connected to, for example, a plurality of capacitance detection circuits 21, 22, 23, and 24 connected to the capacitance sensors 1 to 4, and to the plurality of capacitance detection circuits 21 to 24, respectively. A / D converters 21a, 22a, 23a, and 24a, and an arithmetic processing unit 25 connected to these A / D converters 21a to 24a are configured.

  Each of the capacitance detection circuits 21 to 24 has a CV conversion function of converting, for example, capacitance (Capacitance) detected by the sensor electrode 7 of each of the capacitance sensors 1 to 4 into voltage (Voltage). . These capacitance detection circuits 21 to 24 include, for example, a known CR charge / discharge time circuit, a circuit for transferring charged charges to a known capacitor, a circuit for measuring impedance, and an oscillation circuit to set the oscillation frequency. It can be configured using a circuit to be measured.

  Each A / D converter 21a-24a converts an analog signal indicating a voltage output from each capacitance detection circuit 21-24 into a digital signal. The arithmetic processing unit 25 includes, for example, a storage unit such as a CPU (not shown), a RAM used as a temporary storage area, a ROM for storing data, and the like.

  The arithmetic processing unit 25 controls the entire input device 100, and compares and determines the capacitance value C based on the digital signals from the A / D converters 21a to 24a to detect the position of the hand. . Further, the arithmetic processing unit 25 has a function as a display control unit that performs display control of the display device 30 and also has a function as an output unit that outputs an output signal such as a control signal to an electric device.

  Each of the capacitance sensors 1 to 4 is formed, for example, separately on a plurality of substrates (not shown) or integrally on one substrate. As this board | substrate, any board | substrates, such as a flexible printed circuit board, a rigid board | substrate, or what combined these, are employable, for example.

  Even if the circuit unit 20 is mounted on the same surface side or the back surface side of the substrate on which the capacitance sensors 1 to 4 are formed and provided integrally, it is mounted separately on another substrate and provided separately. It may be done. Further, when a set of capacitance detection circuit and A / D converter is one circuit element, a plurality of circuit elements may be provided so as to correspond to the number of capacitance sensors.

  The sensor electrode 7 and the shield electrodes 8 and 9 of each of the capacitance sensors 1 to 4 are, for example, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyimide (PI), polyamide (PA), glass epoxy resin, or ceramic. It can be composed of copper, a copper alloy, or a metal member (conductive material) such as aluminum or iron, an electric wire, or the like formed on a substrate made of an insulator such as.

  In addition, it may be necessary to arrange | position each electrostatic capacitance sensor 1-4 so that it may not stand out in appearance depending on the arrangement | positioning aspect. For example, since the display screen D of the display device 30 is a display region, the capacitance sensors 1 to 4 may be arranged on the back side (lower side) of the design panel or the like of the display device 30, but on the front side. In some cases, it may be attached or embedded.

  In such a case, the said board | substrate should be formed with the panel and film material which have transparency, and should just comprise each electrode 7-9 with a transparent electrode. The transparent electrode can be composed of, for example, tin-doped indium oxide (ITO) or a conductive polymer. As the conductive polymer, for example, PEDOT / PSS (polyethylene dioxythiophene / polystyrene sulfonic acid), PEDOT / TsO (polyethylene dioxythiophene / toluene sulfonate), or the like can be used.

  The display device 30 is composed of an LCD, an organic EL, a plasma display, or the like. When the display device 30 is in the operation mode of the electric device, an indicator that can be slid to instruct operation of the electric device is displayed on the display screen D. . In the example shown in FIG. 1, a volume control slide bar 50 is displayed as an indicator so as to form a longitudinal direction in the left-right direction of the display screen D, and a bar 51 indicating the current set value is displayed in the slide bar 50. ing. The slide bar 50 is assigned a numerical value that becomes smaller toward the left side.

  Note that examples of electrical devices include devices that require human operation, such as car navigation systems, car audio systems, car air-conditioning systems, car TV systems, and systems used outside these vehicles. In addition to the slide bar 50, the indicator includes various modes such as an operation meter, an operation dial, and an operation knob.

  Next, an operation process of the electric device using the electric device input device configured as described above will be described. FIG. 3 is a diagram illustrating an installation example of the electric device including the input device for the electric device according to the first embodiment of the present invention. FIG. 4 is a flowchart showing an operation processing procedure of the electric device provided with the input device. FIG. 5 is a diagram for explaining the display state of the indicator based on the relationship between the operation position and the sensor output in the input device.

  Here, as shown in FIG. 3, it is assumed that the electric device is a car navigation device mounted on an instrument panel 151 of the vehicle 150, for example, and the display device 30 is a display device of this car navigation device. In addition, on the outside of the display device 30, the capacitance sensors 1, 2 are on a straight line that crosses the display screen D, and on the other straight line that intersects the straight line with the display screen D, the capacitance sensors 3, 3. Assume that an input device 100 in which 4 is provided is provided.

  As an operation process of the electric device, a case where the volume of the car navigation device is operated using the slide bar 50 as shown in FIG. 1 will be described as an example. As shown in FIG. 4, first, in a state where the slide bar 50 is not displayed on the display screen D of the display device 30, the arithmetic processing unit 25 performs the capacitance measured by each of the capacitance sensors 1 to 4. The electrostatic capacitance value C (C1 to C4) based on is detected (step S100).

  Next, based on the detected capacitance values C1 to C4, it is determined whether or not the operation mode has been started (step S102). In this operation mode start determination, for example, whether or not the total sum of the capacitance values C1 to C4 is equal to or greater than a preset threshold value and all the capacitance values C1 to C4 are increased. It is done by judging. That is, here, the hand 6 (see FIG. 5) approaches within the detection range of the sensor unit 10, and it is determined whether or not the hand 6 is within a predetermined distance from the display device 30.

  If it is determined that the operation mode has not been started (N in step S102), the process proceeds to step S100 and the process is repeated. If it is determined that the operation mode has been started (Y in step S102), the display device 30 is controlled to display the slide bar 50 on the display screen D (step S104).

  At this time, a bar 51 is displayed in the slide bar 50 at a position indicating the currently set volume value of the car navigation device. And the arithmetic processing part 25 judges whether the bar 51 is a movable state based on each electrostatic capacitance value C1-C4 (step S106). In other words, in order to prevent malfunction, the input device 100 cannot operate the bar 51 only by starting the operation mode.

  In the determination process in step S106, the position of the hand 6 (or the finger 6a, see FIG. 5, the same applies hereinafter) is in front of the display position of the bar 51 (or the position corresponding to the display position of the bar 51). This is done by determining whether or not there is. When it is determined that the bar 51 is not in a movable state (N in Step S106), the display processing for waiting for the movable state (Y in Step S106) and informing the operator of the movable state is performed. Performed (step S108).

  The display process in step S108 is performed, for example, by blinking the display of the bar 51 or changing the display color of the bar 51. In this way, it is possible to easily inform the operator of the state in which the bar 51 can be operated. The arithmetic processing unit 25 detects the operation position of the bar 51 by detecting the position of the hand 6 (step S110), and changes the display of the slide bar 50 so that the bar 51 is displayed at the detected operation position. (Step S112).

  Here, since the slide bar 50 includes a bar 51 that moves in the horizontal direction (left-right direction), the sensor outputs (capacitance values) of the capacitance sensors 3 and 4 disposed on the left and right sides of the display device 30. Focus only on C3, C4). The sensor outputs (capacitance values C1 and C2) of the capacitance sensors 1 and 2 arranged above and below the display device 30 are appropriately weighted and corrected, for example, so as not to affect the detection of the operation position of the bar 51. What is necessary is just to make it process. Thereby, the position in the left-right direction can be reliably detected without being affected by the position in the vertical direction of the hand 6.

  The operation position of the bar 51 can be determined as follows. That is, for example, when the hand 6 or the finger 6a is in the vicinity of the left end of the display screen D of the display device 30 as in the slide bar 50 shown in FIG. 5A, the sensor output 3a of the capacitance sensor 3 is The sensor output 4a of the electrostatic capacity sensor 4 becomes smaller. In such a case, the bar 51 is displayed at a position corresponding to the position of the hand 6 or the like in the vicinity of the left end in the slide bar 50.

  From this state, as shown in FIG. 5 (B), when the hand 6 or the like is moved slightly to the right from the state shown in FIG. 5 (A) of the display screen D, the sensor output 3a decreases slightly, and the sensor output 4a increases a little. As a result, it can be seen that the hand 6 or the like has moved to the right side, so that the bar 51 follows the movement of the hand 6 or the like within the slide bar 50 and is displayed at a position corresponding to this position.

  Further, as shown in FIG. 5C, when the hand 6 or the like is moved to the right side of the center of the display screen D as it is, the sensor output 4a exceeds the sensor output 3a, and FIG. As shown, when the hand 6 or the like is in the vicinity of the right end of the display screen D, the sensor output 4a increases and the sensor output 3a decreases as opposed to the state shown in FIG. Thus, the operation position of the bar 51 is displayed in accordance with the position of the hand 6 or the like detected based on the capacitance value.

  Then, the arithmetic processing unit 25 outputs a signal for changing the set value of the volume in accordance with the detected operation position to the volume control device of the navigation device (step S114), and the operation of the bar 51 by the operator is completed. Then, it is determined whether the desired set value is confirmed and the operation mode is terminated (step S116).

  This operation mode end determination is made, for example, by checking whether or not the total sum of the capacitance values C1 to C4 falls below a preset threshold value and all the capacitance values C1 to C4 are decreased. It is done by judging. That is, here, it is determined whether or not the hand 6 that is within the detection range of the sensor unit 10 is separated and is separated from the display device 30 by a predetermined distance.

  If it is determined that the operation mode has not been completed (N in step S116), the process proceeds to step S110, the operation position of the bar 51 is detected, and the subsequent processing is repeated. If it is determined that the operation mode has been completed (Y in step S116), the series of operation processing according to this flowchart is terminated.

  Note that the end of the operation mode in step S116 may be performed as follows based on the capacitance values C1 to C4. That is, when the operation of the bar 51 by the operator is finished, (1) the hand 6 is stopped and then released, (2) the hand 6 is brought close to the display screen D and then released (3) with respect to the slide bar 50 When there is an operation such as moving the hand 6 in a perpendicular direction, it may be determined to end the operation mode.

  In the case of the above (1), after the relationship between the capacitance values C1 to C4 has not changed for a predetermined time within a predetermined range, the capacitance values C1 to C4 have become a predetermined value or less. Can be determined if. Also, in the case of (2) above, when the relationship between the capacitance values C1 to C4 is within a predetermined range, the value immediately becomes a predetermined value or less immediately after the value increases by a predetermined value or more. Can be judged.

  Furthermore, in the case of the above (3), the change in the capacitance values C1 to C4 indicates the direction perpendicular to the slide bar 50 (for example, the hand 6 moves away from the display screen D or the upper and lower sides of the display screen D). It can be determined when the change is such that it has moved straight in the direction). As described above, the end of the operation mode is determined by detecting that the operation of the bar 51 by the operator is completed.

  In the above description, the case of operating the volume of the car navigation device has been described as an example. In addition, the image quality adjustment operation such as the brightness and hue of the display screen D, the zoom adjustment operation of the display screen D, the car air conditioner The present invention can be applied to various operations such as a temperature adjustment operation in the system, a wind direction adjustment operation, and a tuner frequency adjustment operation in a car audio system.

  Here, each electrostatic capacitance sensor 1-4 of the sensor part 10 may be arrange | positioned as shown in FIG. In FIG. 6, only the capacitance sensors 3 and 4 are described and illustrated, but the capacitance sensors 1 and 2 may have the same configuration. That is, in each of the capacitance sensors 1 to 4, the surface including the main surface of at least one capacitance sensor and the surface including the main surface of the display device 30 form an obtuse angle on the front surface side of the display device 30. As described above, the display device 30 may be inclined.

  In FIG. 6, specifically, the surface including the main surface 3b of the capacitance sensor 3, the surface including the main surface 4b of the capacitance sensor 4, and the surface including the main surface 30b of the display device 30 are hands. Capacitance sensors 3 and 4 are inclined so that an obtuse angle is formed on the front side where 6 approaches / separates.

  Note that the inclination angle of each of the capacitance sensors 1 to 4 can be adjusted to an arbitrary angle as shown by an arrow in the figure by a mechanical arrangement adjustment mechanism (not shown). The angle adjustment can be performed, for example, by operating a mechanical dial adjustment means provided in an electric device or an indicator displayed on the display screen D to control the arrangement adjustment mechanism.

  Thus, if the arrangement angle of each of the capacitance sensors 1 to 4 of the sensor unit 10 can be adjusted, the detection range and detection sensitivity by the sensor unit 10 can be finely adjusted. Therefore, for example, the stroke size of the hand 6 necessary for the operation of the bar 51 can be arbitrarily set, and an optimum operating environment can be provided for each operator when there are a plurality of operators.

  FIG. 7 is a diagram showing an indicator in the input device of the electric device according to the second embodiment of the present invention. In the following description, the same reference numerals are assigned to portions that overlap the already described portions, and description thereof is omitted. The indicator of the input device 100 according to the first embodiment described above is a volume control slide bar 50 having a longitudinal direction in the left-right direction of the display screen D as shown in FIG. Such an indicator is different in the following points.

  That is, the indicator is a slide bar 50A for air volume control of the car air conditioner system, and is displayed so as to form a longitudinal direction in the vertical direction (vertical direction) of the display screen D. The slide bar 50A is assigned a numerical value that becomes smaller toward the lower side, and a bar 51 is displayed.

  In this case, since the slide bar 50A has a structure including the bar 51 that moves in the vertical direction (up and down direction), the sensor outputs (capacitance value C1) of the capacitance sensors 1 and 2 disposed above and below the display device 30. , C2), it is possible to reliably detect the vertical position of the hand 6 and perform the operations as described above. Since other configurations and operational effects are the same as those of the first embodiment, description thereof will be omitted.

  FIG. 8 is a diagram illustrating an indicator in the input device of the electrical apparatus according to the third embodiment of the present invention. FIG. 9 is a diagram for explaining the display state of the indicator based on the relationship between the operation position and the sensor output in the input device. In the first and second embodiments described above, the slide bars 50 and 50A are taken as an example of the indicator. However, as shown in FIG. 8, the indicator of the present embodiment is a circular slide bar 50B. It is different.

  The slide bar 50B is, for example, a temperature control slide bar of a car air conditioner system, and is displayed on the display screen D so as to form an arc. The slide bar 50B is assigned a numerical value that becomes smaller toward the left side along the shape, and the bar 51 is displayed.

  In this case, the arithmetic processing unit 25 of the circuit unit 20 compares the sensor outputs (capacitance values C1 and C2) of the capacitance sensors 1 and 2 of the sensor unit 10 to detect the vertical position of the hand 6 and the like. Then, the sensor outputs (capacitance values C3 and C4) of the capacitance sensors 3 and 4 are compared to detect the position of the hand 6 and the like in the left-right direction.

  Here, a case where the bar 51 is in the lower left side with respect to the display screen D in advance will be described. As shown in FIG. 9A, the operation mode as described above is started, and the bar 51 can be moved by detecting that the position of the hand 6 or the like faces the display position of the bar 51. In this case, the state notification display process is performed by flashing the bar 51 or the like.

  At this time, the sensor outputs 2a and 3a of the capacitance sensors 2 and 3 are increased, and the sensor outputs 1a and 4a of the capacitance sensors 1 and 4 are decreased. Therefore, the bar 51 is displayed at a position corresponding to the position of the hand 6 or the like in the vicinity of the lower left side of the slide bar 50B. From this state, as shown in FIG. 9B, when the hand 6 or the like is moved to the upper left side with respect to the display screen D on the slide bar 50B, the sensor output 1a gradually increases and the sensor output 2a gradually decreases. To do.

  At the same time, the sensor output 3a slightly increases and decreases a little while the output is high, and the sensor output 4a changes slightly increasing while the output is low. As a result, it can be seen that the hand 6 or the like has moved to the upper left side, so that the bar 51 is caused to follow the movement of the hand 6 or the like within the slide bar 50B and displayed at a position corresponding to this position.

  Next, as shown in FIG. 9C, when the hand 6 or the like is moved to the upper center of the display screen D on the slide bar 50B, the sensor output 1a gradually increases and the sensor output 2a gradually decreases. The sensor output 3a gradually decreases and the sensor output 4a gradually increases. At this time, the sensor outputs 3a and 4a have substantially the same value. As a result, it can be seen that the hand 6 or the like has moved to the center upper side, so the bar 51 is displayed accordingly.

  In the case shown in FIGS. 9D and 9E, the relationship between the sensor outputs 1a to 4a is almost opposite to the case shown in FIGS. 9B and 9A. Therefore, according to the input device according to the present embodiment, the position of the hand 6 or the like on the slide bar 50B is surely detected, the operation position of the bar 51 is displayed, and the set value of the temperature determined thereby is set as the car air conditioner system. Can be output. In addition, when each sensor output 1a-4a represents that the hand 6 etc. moved in the position which does not follow the slide bar 50B etc., it will prevent a malfunction if it does not change the operation position of the bar 51. can do.

  FIG. 10 is a diagram illustrating an overall configuration of an input device for an electrical apparatus according to the fourth embodiment of the present invention. FIG. 11 is a diagram illustrating a capacitance detection circuit of an input device of an electrical apparatus according to the fifth embodiment of the present invention. As shown in FIG. 10, in the input device according to the fourth embodiment, the arrangement mode and configuration of the capacitance sensors 1 to 4 of the sensor unit 10 are the same as those in the above-described embodiment.

  The difference is that one electrostatic capacity detection circuit 28 and one A / D converter 28a are provided in the circuit unit 20A, and the electrostatic capacity detection circuit 28 and the shield drive circuit 26 are connected via switches SW31 to SW34 and SW41 to 44, respectively. In other words, it is connected to the sensor electrode 7 and the shield electrodes 8 and 9 of the electrostatic capacitance sensors 1 to 4.

  That is, the sensor electrodes 7 of the capacitance sensors 1 to 4 are connected to the capacitance detection circuit 28 via the switches SW31 to 34, respectively, and the shield electrodes 8 and 9 of the capacitance sensors 1 to 4 are respectively connected to the switches. It is connected to the shield drive circuit 26 via SW41 to 44. Further, the arithmetic processing unit 25 performs switch control (ON / OFF control) of the switches SW31 to SW34 and SW41 to 44 and control of timing for taking in data from the A / D converter 28a.

  For example, when the capacitance sensor 1 detects the capacitance, the sensor electrode 7 of the capacitance sensor 1 is statically closed by closing the switches SW31 and SW42 to 44 and opening the switches SW32 to 34 and SW41. Connected to the capacitance detection circuit 28, the sensor electrodes 7 of the capacitance sensors 2 to 4 are connected to the shield drive circuit 26. Similarly, each of the capacitance sensors 2 to 4 detects the capacitance.

  If comprised in this way, the number of electrostatic capacitance detection circuits can be reduced by switching the connection of the electrostatic capacitance sensors 1-4 and the electrostatic capacitance detection circuit 28 temporally, for example at high speed. Although the switch control and the timing control are performed by the arithmetic processing unit 25, the switch control is periodically performed separately from the arithmetic processing unit 25, and the output at each switching is held. You may comprise so that it may be connected to D converter 28a.

  As shown in FIG. 11, the capacitance detection circuits 21 to 24 and 28 of the input device according to the fifth embodiment are configured to perform a differential operation. Each of the capacitance sensors 1 to 4 has a configuration including a dummy sensor electrode (dummy electrode) 19 in addition to the sensor electrode 7 and the shield electrodes 8 and 9.

  Specifically, for example, the sensor electrode 7 is connected to the plus side input end of the differential operation circuit, and the dummy electrode 19 is connected to the minus side input end, and the value of the capacitance Cb is subtracted from the value of the capacitance Ca. The output value is compared with a predetermined threshold value by a comparator or the like to detect the hand 6 or the like.

  As an operation of such capacitance detection circuits 21 to 24, 28, for example, when the switch S1 is open (OFF), the switch S2 is grounded (GND), and the switch S3 is closed (ON), When switch S3 is opened (OFF), switch S2 is switched to Vr, and switch S1 is connected to the inverting input of the operational amplifier, capacitances Ca and Cf are charged with VaVr, and capacitances Cb and Cf are charged with CbVr. The

  Next, after the switch S1 is opened (OFF) and the switch S2 is grounded (GND), the output voltage V when the switch S1 is grounded (GND) is measured. The voltage at this time is V / Vr = {(Cf + Ca) / Cf} − {(Cf + Cb) / Cf}, and a voltage corresponding to the ratio between the capacitance Ca and the capacitance Cb is output.

  Thus, by setting the capacitance detection circuits 21 to 24 and 28 to a differential operation (differential circuit), the temperature characteristics of the circuit can be offset and common mode noise can be reduced. At this time, for example, the dummy electrode 19 is connected to the negative input end of the differential amplifier circuit. If the dummy electrode 19 is capacitively coupled to the hand 6 or the like, the sensitivity of the sensor itself is lowered. Therefore, the area of the dummy electrode 19 is made sufficiently small with respect to the sensor electrode 7 or another shield electrode 47 having the same potential is provided between the dummy electrode 19 and the hand 6 etc. It is necessary to reduce the capacitive coupling.

  In the above-described embodiment, the case where four capacitance sensors of the sensor unit 10 are provided has been described as an example. However, at least two are sufficient, for example, when there are three, the display device 30. It is also possible to detect the two-dimensional position by arranging the triangles surrounding the display screen D at different positions outside the screen, or to improve the resolution by increasing the number of capacitance sensors. Good.

  Further, the capacitance sensors may be arranged in a three-dimensional arrangement so as to detect the position of the three-dimensional hand 6 or the like. In addition, although the circuit unit 20 is configured to use the output of the capacitance detection circuit as it is, the initial capacitance value when there is no hand 6 or other object in the vicinity of each of the capacitance sensors 1 to 4 is used. The position of the hand 6 or the like may be detected using a difference value from the initial capacitance value as the capacitance value.

1-4 Electrostatic Capacitance Sensor 6 Hand 7 Sensor Electrode 8, 9 Shield Electrode 10 Sensor Unit 20 Circuit Unit 21-24 Capacitance Detection Circuit 21a-24a A / D Converter 25 Arithmetic Processing Unit 26 Shield Drive Circuit 28 Electrostatic Capacity detection circuit 28a A / D converter 100 Input device 150 Vehicle 151 Instrument panel

Claims (8)

Display means for displaying a slide-movable indicator for instructing the operation of the electric device;
A plurality of capacitance sensor units provided at different positions outside the display means;
Detecting means for detecting an operation position of the indicator by detecting capacitance values based on capacitances detected by the plurality of capacitance sensor units;
An input device for an electrical device, comprising: display control means for changing the display of the indicator based on the detected operation position. The input device for an electric device according to claim 1, further comprising output means for outputting an output signal to the electric device according to the detected operation position of the indicator. The input of the electric device according to claim 1, wherein the plurality of capacitance sensor units include first and second capacitance sensor units arranged on a straight line crossing the display unit. apparatus. The electric capacity according to claim 3, wherein the plurality of capacitance sensor units include a third capacitance sensor unit provided at a position different from that of the first and second capacitance sensor units. Device input device. When the total sum of the capacitance values detected by the plurality of capacitance sensor units is equal to or greater than a preset threshold value and all the capacitance values are increasing, The operation of the indicator is started. The input device for an electric device according to any one of claims 1 to 4, wherein the operation of the indicator is started. When the total sum of the capacitance values detected by the plurality of capacitance sensor units is less than a preset threshold value and all the capacitance values are decreasing, the detection means The operation of the indicator is terminated. The electric device input device according to claim 1, wherein the operation of the indicator is terminated. In the plurality of capacitance sensor units, the surface including the main surface of at least one capacitance sensor unit and the surface including the main surface of the display unit form an obtuse angle on the front side of the display unit. The input device for an electric device according to claim 1, wherein the input device is inclined with respect to the display unit. The electric device input device according to claim 7, wherein the at least one capacitance sensor unit is arranged such that an inclination angle with respect to the display unit can be adjusted.

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