JP2012022635A - Electrostatic capacitance type proximity sensor device, and electrostatic capacitance type motion detection device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrostatic capacitance type proximity sensor that detects the distance between a sensor surface and a body to be detected and precisely detect the position of the body to be detected on the sensor surface, and an electrostatic capacitance type motion detection device using the same.SOLUTION: An electrostatic capacitance type proximity sensor includes X-axial electrodes 14a to 14f, Y-axial electrodes 15a to 15f, a driver circuit 20, a detection circuit 21 which detects a signal output from a detection electrode, a CPU 19 which computes the position of the body to be detected, and a switching control circuit 18 which connects an electrode as a driving electrode to the driver circuit 20 and also connects an electrode as the detection electrode to the detection circuit 21. The switching control circuit 18 alternates a first detection mode in which the X-axial electrodes 14a to 14f or Y-axial electrodes 15a to 15f are selected as driving electrodes or detection electrodes and a second detection mode in which the X-axial electrodes 14a to 14f or Y-axial electrodes 15a to 15f are selected as driving electrodes and two adjacent electrodes of the other are selected as detection electrodes.

Description

  The present invention relates to a proximity sensor device that detects the position of a detection object, and in particular, a capacitance proximity sensor device that detects the proximity of a detection object by a change in capacitance, and a capacitance motion using the same. The present invention relates to a detection device.

  Conventionally, capacitive touch panels have been proposed as input devices for various devices (see, for example, Patent Document 1). Such a touch panel includes a plurality of X-axis electrodes and a plurality of Y-axis electrodes arranged in a matrix via an insulating layer. When the operator presses his / her finger against an arbitrary position on the display device of the touch panel, a part of the lines of electric force formed between the plurality of X-axis electrodes and the plurality of Y-axis electrodes are pulled out to the fingers, and each X The capacitance formed between the shaft electrode and each Y-axis electrode is reduced. The touch position is detected by signals output from each X-axis electrode and each Y-axis electrode in accordance with the change in capacitance.

JP 2010-61598 A

  By the way, since a touch panel detects a to-be-detected object on the premise of the contact operation to a display apparatus, there exists a problem that a detection range is restrict | limited on the surface of a display apparatus, or the very vicinity of the surface. For this reason, in the conventional touch panel, it was difficult to detect both the approach of the detected object and the position of the detected object on the surface of the display device.

  The present invention has been made in view of the above points, and is capable of detecting the distance between the sensor surface and the detected object and detecting the position of the detected object on the sensor surface of the detected object with high accuracy. It is an object of the present invention to provide a capacitive proximity sensor and a capacitive motion detection device using the same.

  The capacitive proximity sensor device of the present invention has an arbitrary angle so as to form a capacitance between the plurality of X-axis electrodes arranged in the X-axis direction and the plurality of X-axis electrodes. A plurality of Y-axis electrodes, a drive circuit for outputting a drive voltage to be applied to an electrode serving as a drive electrode among the plurality of X-axis electrodes and the plurality of Y-axis electrodes, and the plurality of X-axis electrodes And a detection circuit that detects a signal output from an electrode serving as a detection electrode among the plurality of Y-axis electrodes, and a detection result of the detection circuit, the X-axis direction, the Y-axis direction, and Z with respect to a detection reference plane Of the plurality of X-axis electrodes and the plurality of Y-axis electrodes, an electrode that serves as the drive electrode is connected to the drive circuit and serves as the detection electrode. Switching means for connecting an electrode to the detection circuit; The switching means connects at least two X-axis electrodes arranged apart from each other to the detection circuit as the detection electrodes, and drives the at least two Y-axis electrodes arranged apart from each other. A first detection mode connected to the drive circuit as an electrode, and at least one Y-axis electrode connected to the drive circuit as the drive electrode, and at least two adjacent X-axis electrodes as the detection electrode The second detection mode is connected to the detection circuit and sequentially switches the electrodes to be the detection electrodes within the X-axis electrode.

  According to this configuration, in the first detection mode, signals corresponding to the capacitance formed between the X-axis electrodes and the Y-axis electrodes that are arranged apart from each other are output from the detection electrodes. The detection sensitivity of the detection object with respect to the Z-axis direction (height direction) of the detection reference surface (sensor surface) can be increased. In the second detection mode, the output signal becomes the maximum value when the X-axis electrode in the vicinity of the detected object position on the sensor surface is switched as the detection electrode, so that the detected object position on the sensor surface is accurate. It can be detected well. Therefore, it is possible to realize a capacitive proximity sensor that can detect the distance between the sensor surface and the detected object and can accurately detect the position of the detected object on the sensor surface of the detected object.

  According to the present invention, in the capacitance type proximity sensor device, in the first detection mode, the switching unit uses the at least two X-axis electrodes arranged apart from each other as the detection electrodes in the detection circuit. An electrode pattern that connects to the drive circuit using at least two Y-axis electrodes that are connected and spaced apart as the drive electrode, and at least two Y-axis electrodes that are spaced apart as the detection electrode The electrode pattern is connected to the detection circuit, and at least two X-axis electrodes arranged apart from each other are switched as the drive electrodes to the drive circuit.

  With this configuration, a signal corresponding to the capacitance formed between the X-axis electrodes and between the Y-axis electrodes arranged apart from each other in the X-axis direction and the Y-axis direction is output from the detection electrodes. Therefore, it is possible to increase the detection sensitivity of the detection target with respect to the height direction of the sensor surface. For this reason, the distance between the sensor surface and the detection target can be detected with high accuracy.

  In the capacitance-type proximity sensor device according to the present invention, in the first detection mode, the switching unit includes the X-axis electrode at one end in the X-axis direction and the X-axis electrode at the other end. Among the end electrodes including the Y-axis electrode at one end in the Y-axis direction and the Y-axis electrode at the other end, at least one of the end electrodes is used as the detection electrode in the detection circuit. In addition to being connected, at least one of the end electrodes is connected to the drive circuit as the drive electrode, and the electrodes serving as the detection electrodes are sequentially switched within the end electrode.

  With this configuration, a signal corresponding to the distance between each end electrode and the object to be detected is output from the detection electrode, so the distance in the height direction between the sensor surface and the object to be detected can be accurately detected. can do.

  According to the present invention, in the capacitive proximity sensor device, in the second detection mode, the switching unit uses at least one Y-axis electrode as the drive electrode and at least two adjacent X-axis electrodes. The electrode electrode is connected to the detection circuit together as the detection electrode, the electrode pattern for sequentially switching the electrode to be the detection electrode in the X-axis electrode, and at least one X-axis electrode as the drive electrode to the drive circuit And connecting at least two adjacent Y-axis electrodes as the detection electrodes to the detection circuit, and switching between electrode patterns that sequentially switch the electrodes to be the detection electrodes within the Y-axis electrodes. To do.

  With this configuration, the output signal becomes the maximum value when the X-axis electrode and the Y-axis electrode in the vicinity of the detected object position on the sensor surface are switched as the detection electrodes, so that the detected object position on the sensor surface can be accurately determined. Can be detected.

  Also, in the capacitance proximity sensor device according to the present invention, in the first detection mode, the switching unit divides the detection reference plane into at least two detection target regions, and the detection target regions The X-axis electrode located at both ends in the X-axis direction is connected to the drive circuit as the drive electrode, and the Y-axis electrode located at both ends in the Y-axis direction is connected to the detection circuit as the detection electrode And the said calculating means calculates a to-be-detected body position for every said each detection object area | region, It is characterized by the above-mentioned.

  With this configuration, a signal corresponding to the capacitance formed between the X-axis electrodes at both ends in the X-axis direction and the Y-axis electrodes at both ends in the Y-axis direction is output from the detection electrodes for each detection target region. Therefore, it is possible to detect the detected object position with respect to the sensor surface with high accuracy.

  Also, in the capacitance proximity sensor device according to the present invention, in the first detection mode, the switching unit divides the detection reference plane into at least two detection target regions, and the detection target regions The Y-axis electrodes located at both ends in the Y-axis direction are connected to the drive circuit as the drive electrodes, and the X-axis electrodes located at both ends in the X-axis direction are connected to the detection circuit as the detection electrodes And the said calculating means calculates a to-be-detected body position for every said each detection object area | region, It is characterized by the above-mentioned.

  With this configuration, for each detection target region, a signal corresponding to the capacitance formed between the Y-axis electrodes at both ends in the Y-axis direction and the X-axis electrodes at both ends in the X-axis direction is output from the detection electrodes. Therefore, it is possible to detect the detected object position with respect to the sensor surface with high accuracy.

  According to the present invention, in the capacitive proximity sensor device, the detection circuit includes a differential amplifier circuit having a positive terminal and a negative terminal, and an output of one detection electrode switched in the first detection mode. The signal is input to the positive electrode terminal, the output signal of the other detection electrode is input to the negative electrode terminal, the output signal of one detection electrode switched in the second detection mode is input to the positive electrode terminal, and the other detection electrode The output signal is input to the negative terminal.

  With this configuration, the output signal of the detection electrode pair in the first detection mode and the second detection mode can be amplified by one differential amplifier circuit, so that the circuit configuration can be simplified. Further, the influence of noise can be reduced by differentially amplifying the output signals of the detection electrode pair.

  The capacitance type motion detection device of the present invention processes the position information of the detected object calculated by the capacitance type proximity sensor device and the calculation circuit with a predetermined time constant, and the motion of the detected object is detected. Motion detection means for performing detection.

  According to this configuration, since the distance between the detected object and the sensor surface and the touch position of the detected object with respect to the sensor surface can be accurately detected, the approach of the detected object to the sensor surface and the detected object with respect to the sensor surface It is possible to realize a capacitive motion detection device that can detect both of the touch operations.

  According to the present invention, a capacitive proximity sensor that can detect the distance between the sensor surface and the detected object and can accurately detect the position of the detected object on the sensor surface of the detected object and the same are used. A capacitive motion detection device can be provided.

1 is a configuration diagram of a capacitive proximity sensor device according to an embodiment of the present invention. FIG. (A) is a schematic diagram of electrode arrangement | positioning of the sensor part of the capacitive proximity sensor apparatus which concerns on embodiment of this invention, (b) is an AA arrow directional cross-sectional view of a sensor part. . It is a flowchart which shows the procedure at the time of the to-be-detected body detection of the capacitive proximity sensor apparatus which concerns on embodiment of this invention. It is a transition diagram of the electrode pattern in the 1st detection mode of the capacitive proximity sensor apparatus which concerns on embodiment of this invention. It is a transition diagram of the electrode pattern in the 2nd detection mode of the capacitive proximity sensor apparatus which concerns on embodiment of this invention. (A)-(c) is a figure which shows an example of the electrode connection of the detection electrode in the 1st detection mode of the electrostatic capacitance type proximity sensor apparatus which concerns on embodiment of this invention. (A), (b) is a figure which shows an example of the electrode connection in the case of inputting the output signal of a detection electrode differentially in the 2nd detection mode of the capacitive proximity sensor apparatus which concerns on embodiment of this invention. It is. (A), (b) is a figure which shows an example of the electrode connection in the case of carrying out the single end input of the output signal of a detection electrode in the 2nd detection mode of the capacitive proximity sensor apparatus which concerns on embodiment of this invention. It is. It is a conceptual diagram which shows the detection principle in the electrostatic capacitance type proximity sensor apparatus which concerns on embodiment of this invention. It is a figure which shows the change of the to-be-detected body position and the difference of an electrostatic capacitance in the electrostatic capacitance type proximity sensor apparatus which concerns on embodiment of this invention. (A), (b) is a figure which shows the detection principle of the to-be-detected body in the Z-axis direction of the capacitive proximity sensor which concerns on the form of embodiment of this invention. (A) is a figure which shows the detection result of the to-be-detected body with respect to the X-axis direction in the 1st detection mode of the capacitive proximity sensor apparatus which concerns on embodiment of this invention, (b) is 1st It is a figure which shows the detection result of the to-be-detected body with respect to the Y-axis direction in this detection mode. It is a transition figure showing other examples of an electrode pattern in the 1st detection mode of a capacity type proximity sensor device concerning an embodiment of the invention.

  The present inventors paid attention to the electrode arrangement of the capacitive touch panel and the detection principle of the capacitive proximity sensor device. The capacitive touch panel has an electrode arrangement in which a plurality of X-axis electrodes arranged in parallel and a plurality of Y-axis electrodes arranged in parallel are arranged in a matrix, and serve as detection electrodes. The detected object position is detected while sequentially switching the electrodes within the X-axis electrode or the Y-axis electrode. On the other hand, as described later, the capacitive proximity sensor device detects an object to be detected via a capacitance formed between a detection electrode and a drive electrode that are arranged apart from each other.

  In the capacitive touch panel, the present inventors apply the detection principle of the capacitive proximity sensor device, and are formed between X-axis electrodes (between Y-axis electrodes) arranged apart from each other. It has been found that the distance between the object to be detected and the sensor surface can be detected via capacitance. The first detection mode for detecting the distance between the detection target and the sensor surface by the electrostatic capacitance formed between the electrodes arranged apart from each other, and between the adjacent X-axis electrodes (Y-axis electrodes) The second detection mode for detecting the position of the detected object on the sensor surface is switched by the capacitance formed between the detected object and the sensor surface. The present inventors have found that the position of the detected object can be detected together and have completed the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a configuration diagram of a capacitive proximity sensor device according to the present embodiment. As shown in FIG. 1, the proximity sensor device according to the present embodiment includes a sensor unit 11 that detects a touch operation and proximity of the detection target, and an output signal detected by the sensor unit 11. And a control circuit unit 12 for calculating the position.

  The sensor unit 11 includes six X-axis electrodes 14a to 14f arranged on the substrate 13 and six Y-axis electrodes 15a to 15f arranged orthogonal to the X-axis electrodes 14a to 14f. Each of the X-axis electrodes 14a to 14f and each of the Y-axis electrodes 15a to 15f are arranged so as to be separated from each other so that a capacitance is formed between the other electrodes. The X-axis electrodes 14a to 14f and the Y-axis electrodes 15a to 15f are arranged in a matrix via an insulating glass substrate 31 (see FIG. 2).

  An X-axis multiplexer 16 is connected to one end of each X-axis electrode 14a to 14f. The X-axis multiplexer 16 switches the connection of the plurality of X-axis electrodes 14a to 14f as a drive electrode for applying a drive voltage or a detection electrode for detecting a detection target. A Y-axis multiplexer 17 is connected to one end of each Y-axis electrode 15a to 15f. The Y-axis multiplexer 17 switches the connection of the Y-axis electrodes 15a to 15f as a drive electrode that applies a drive voltage or a detection electrode that detects a detection target. In the capacitive proximity sensor device according to the present embodiment, the detected object position is detected while switching the connection of the X-axis electrodes 14a to 14f and the Y-axis electrodes 15a to 15f in accordance with the detection direction.

  The control circuit unit 12 is a switching control circuit 18 that controls switching of the X-axis multiplexer 16 and the Y-axis multiplexer 17 of the sensor unit 11, and signals output from the X-axis electrodes 14a to 14f and the Y-axis electrodes 15a to 15f. Thus, a CPU 19 is provided as a calculation means for calculating the detected object position. Between the CPU 19 and the switching control circuit 18, there is provided a drive circuit 20 for applying a drive voltage to each of the X-axis electrodes 14a to 14f and Y-axis electrodes 15a to 15f switched as drive electrodes, and as a detection electrode. A detection circuit 21 that detects output signals of the switched X-axis electrodes 14a to 14f and Y-axis electrodes 15a to 15f is provided.

  The switching control circuit 18 is connected to the X-axis multiplexer 16 and the Y-axis multiplexer 17 of the sensor unit 11 and is also connected to the drive circuit 20 and the detection circuit 21. The switching control circuit 18 is connected to the CPU 19 and switches and controls the connection of the X-axis electrodes 14a to 14f and the Y-axis electrodes 15a to 15f by a switching control signal from the CPU 19. In response to a switching control signal from the CPU 19, the switching control circuit 18 is connected to the X-axis electrodes 14a to 14f and Y-axis electrodes 15a to 15f (hereinafter simply referred to as driving electrodes) that serve as driving electrodes via the X-axis multiplexer 16 and the Y-axis multiplexer 17. Are connected to the drive circuit 20, and X-axis electrodes 14 a to 14 f and Y-axis electrodes 15 a to 15 f (hereinafter also simply referred to as detection electrodes) serving as detection electrodes are connected to the detection circuit 21.

  The drive circuit 20 includes an oscillation circuit (not shown), and applies a drive voltage to the X-axis electrodes 14a to 14f and the Y-axis electrodes 15a to 15f as drive electrodes. Application of the drive voltage is controlled by the CPU 19.

  The detection circuit 21 includes an amplification circuit 22 having a positive terminal and a negative terminal, and an A / D converter 23 that performs A / D conversion on the output signal amplified by the amplification circuit 22. The detection circuit 21 detects output signals from the X-axis electrodes 14a to 14f and the Y-axis electrodes 15a to 15f as detection electrodes.

  X-axis electrodes 14 a to 14 f and Y-axis electrodes 15 a to 15 f serving as detection electrodes are connected to the positive terminal and the negative terminal of the amplifier circuit 22. The amplification circuit 22 amplifies the output signals of the X-axis electrodes 14a to 14f and the Y-axis electrodes 15a to 15f as detection electrodes by a differential of the output signal between the detection electrodes or a differential with a reference voltage signal. / D converter 23 to output.

  The A / D converter 23 performs filtering processing and digital conversion on the output signal amplified by the amplifier circuit 22 and outputs the result to the CPU 19. A difference value or the like is detected from the output signal input to the CPU 19 by the CPU 19 as a detection circuit. The difference value may be detected by the A / D converter 23. In addition, the CPU 19 as the calculation means calculates the detected object position in the X-axis direction, the Y-axis direction, and the Z-axis direction using the detected output signal.

  Next, the configuration of the sensor unit 11 of the capacitive proximity sensor device according to the present embodiment will be described in detail with reference to FIGS. 2A is a schematic diagram of the electrode arrangement of the sensor unit 11, and FIG. 2B is a cross-sectional view taken along the line AA of the sensor unit 11 shown in FIG. In FIG. 2A, only the X-axis electrodes 14a to 14f and the Y-axis electrodes 15a to 15f are shown.

  As shown in FIGS. 2A and 2B, on the substrate 13, six X-axis electrodes 14 a to 14 f extending in the Y-axis direction are arranged orthogonal to the X-axis direction. . On the X-axis electrodes 14a to 14f, six Y-axis electrodes 15a to 15f extending in the X-axis direction via a glass substrate 31 as an insulating layer are arranged orthogonal to the Y-axis direction. . A protection plate 32 that protects the sensor unit 11 is disposed on the Y-axis electrodes 15a to 15f. In the capacitive proximity sensor device according to the present embodiment, the upper surface of the protection plate 32 becomes the sensor surface 13a as a detection reference surface, and the X-axis direction and the Y-axis direction belonging to the sensor surface 13a and the sensor surface 13a. An object to be detected in the orthogonal Z-axis direction can be detected.

  Next, with reference to FIG. 3, the procedure at the time of detecting the detection object in the capacitive sensor device according to the present embodiment will be described. FIG. 3 is a flowchart showing a procedure at the time of detecting an object to be detected in the capacitive proximity sensor device according to the present embodiment.

  As shown in FIG. 3, in the capacitive proximity sensor device according to the present embodiment, the first detection mode for detecting the distance between the sensor surface 13a and the detected object, and the sensor surface 13a The detected object position is detected using the second detection mode for detecting the detected object position. First, in the first detection mode, the detected object position is detected in the X axis direction, the Y axis direction, and the Z axis direction while switching the X axis electrodes 14a to 14f and the Y axis electrodes 15a to 15f as detection electrodes or drive electrodes. (Step S1). Next, in the detection of the detected object position in the X axis direction, the Y axis direction, and the Z axis direction, the detected object position is calculated from the output signals of the X axis electrodes 14a to 14f and the Y axis electrodes 15a to 15f as detection electrodes. (Step S2).

  Next, the distance between the detected object position calculated in step S2 and the sensor surface 13a is calculated, and compared with a predetermined touch threshold value, it is determined whether or not the detected object is a touch on the sensor surface 13a (step). S3). If the distance between the detected object and the sensor surface 13a is equal to or smaller than the touch threshold, the detected object is detected again from step S1. As the touch threshold value, for example, a predetermined threshold value may be provided for the distance between the detected object position in the X-axis direction, the Y-axis direction, and the Z-axis direction and the sensor surface 13a calculated by the calculation in step 2. In addition, a predetermined threshold may be provided for the intensity of the output signal from the detection electrode in the detection in the X-axis direction, the Y-axis direction, and the Z-axis direction in Step 1.

  If it is determined in step 3 that the detected object is a touch operation on the sensor surface 13a, the position of the detected object in the X-axis direction and the Y-axis direction is detected in the second detection mode (step S4). Next, the X-axis electrodes 14a to 14f and the Y-axis electrodes 15a to 15f that have obtained the maximum output in the detection in the X-axis direction and the Y-axis direction are determined (step S5). From the above results, the detected object position on the sensor surface 13a is specified from the intersection of the X-axis electrodes 14a to 14f and the Y-axis electrodes 15a to 15f from which the maximum output was obtained (step S6).

  Next, electrode patterns used in the first detection mode and the second detection mode in the detection procedure shown in FIG. 3 will be described in detail with reference to FIGS. FIG. 4 is a transition diagram of electrode switching in the first detection mode of the capacitive proximity sensor device according to the present embodiment, and FIG. 5 is a diagram of the capacitive proximity sensor device according to the present embodiment. It is a transition diagram of electrode switching in the second detection mode. 4 and 5, the drive electrode (D) is indicated by a bold line, the detection electrode (S +) connected to the positive terminal of the amplifier circuit 22 is indicated by a one-dot chain line, and is connected to the negative terminal of the amplifier circuit 22. The detection electrode (S−) is indicated by a two-dot chain line.

  As shown in FIG. 4, in the detection of the detection target in the X-axis direction in the first detection mode, the X-axis electrode 14a and the X-axis electrode 14f disposed at both ends in the X-axis direction are switched as detection electrodes, and Y The Y-axis electrode 15a and the Y-axis electrode 15f disposed at both ends in the axial direction are switched as drive electrodes. In the detection of the detection target in the Y-axis direction in the first detection mode, the Y-axis electrode 15a and the Y-axis electrode 15f disposed at both ends in the Y-axis direction are switched as detection electrodes, and are disposed at both ends in the X-axis direction. The X-axis electrode 14a and the X-axis electrode 14f thus formed are switched as drive electrodes.

  In detection of an object to be detected in the Z-axis direction in the first detection mode, four X-axis electrodes 14a and 14f and Y-axis electrodes 15a and 15f arranged at both ends in the X-axis direction and the Y-axis direction are end portions. An object to be detected is detected in this end electrode while sequentially switching the detection electrode and the drive electrode. First, an object to be detected is detected using the X-axis electrode 14a as a detection electrode and the X-axis electrode 14f and the Y-axis electrodes 15a and 15f as drive electrodes. Next, the detection target is detected using the Y-axis electrode 15a as a detection electrode and the X-axis electrodes 14a and 14f and the Y-axis electrode 15f as drive electrodes. Next, the detected object position is detected using the X-axis electrode 14f as a detection electrode and the X-axis electrode 14a and the Y-axis electrodes 15a and 15f as drive electrodes. Next, the detection body position is detected using the Y-axis electrode 15f as a detection electrode and the X-axis electrodes 14a and 14f and the Y-axis electrode 15a as drive electrodes. Finally, the detected object is detected by calculating the addition average of the output signals from the detection electrodes in the Z-axis direction.

  As shown in FIG. 5, in the detection of the detection target in the X-axis direction in the second detection mode, the Y-axis electrodes 15a to 15f are used as drive electrodes, and two X-axis electrodes 14a positioned at one end in the X-axis direction. 14b are detection electrodes. And a to-be-detected object position is detected, switching the electrode used as a detection electrode from the X-axis direction one end to the other end sequentially between adjacent X-axis electrodes 14a-14f.

  In the detection of the detection target position in the Y-axis direction in the second detection mode, the X-axis electrodes 14a to 14f are used as drive electrodes, and the two Y-axis electrodes 15a and 15b located at one end in the Y-axis direction are used as detection electrodes. To do. And a to-be-detected object position is detected, switching the electrode used as a detection electrode from the one end of a Y-axis direction to the other end between adjacent Y-axis electrodes 15a-15f sequentially.

  As described above, in each of the first detection mode and the second detection mode, the distance between the sensor surface 13a and the detected object and the detected object position on the sensor surface 13a are changed while switching the electrode pattern. To detect.

  Next, the detection method in the first detection mode will be described with reference to FIG. FIGS. 6A to 6C are diagrams illustrating an example of electrode connection of the detection electrodes in the first detection mode. As shown in FIG. 6A, in the detection of the detection target in the X-axis direction, one X-axis electrode 14f switched as the detection electrode is connected to the positive terminal of the amplifier circuit 22, and the other X-axis electrode 14 a is connected to the negative terminal of the amplifier circuit 22. A drive voltage is applied from the drive circuit 20 to the Y-axis electrodes 15a and 15f switched as the drive electrodes, and the signals output from the X-axis electrodes 14a and 14f are differentially input to the amplifier circuit 22 and output signal differences. Amplified accordingly.

  As shown in FIG. 6B, in the detection of the detection target in the Y-axis direction, one Y-axis electrode 15a switched as the detection electrode is connected to the positive terminal of the amplifier circuit 22, and the other Y-axis electrode. 15 f is connected to the negative terminal of the amplifier circuit 22. A drive voltage is applied from the drive circuit 20 to the X-axis electrodes 14a and 14f switched as the drive electrodes, and the signals output from the Y-axis electrodes 15a and 15f are differentially input to the amplifier circuit 22 and output signal differences. Amplified accordingly.

  As shown in FIG. 6C, in the detection of the detection target in the Z-axis direction, the X-axis electrode 14 f switched as the detection electrode is input to the positive terminal of the amplifier circuit 22. A reference voltage is input to the negative terminal of the amplifier circuit 22. A drive voltage is applied from the drive circuit 20 to the X-axis electrode 14a and the Y-axis electrodes 15a and 15f that are switched as drive electrodes, and a signal output from the X-axis electrode 14f is input to the amplifier circuit 22 as a single-ended input and a reference voltage. It is amplified according to the difference.

  Next, the detection method in the second detection mode will be described with reference to FIGS. 7 (a) and 7 (b) and FIGS. 8 (a) and 8 (b). In the second detection mode, the output signal of the detection electrode is differentially input or single-ended input to the amplifier circuit 22. FIGS. 7A and 7B are diagrams illustrating an example of electrode connection when the output signal of the detection electrode is differentially input in the second detection mode. As shown in FIG. 7A, in the detection of the detection object in the X-axis direction, one X-axis electrode 14e switched as the detection electrode is connected to the positive terminal of the amplifier circuit 22, and the other X-axis electrode. 14 d is connected to the negative terminal of the amplifier circuit 22. A drive voltage is applied from the drive circuit 20 to the Y-axis electrodes 15a to 15f switched as the drive electrodes, and signals output from the X-axis electrodes 14d and 14e are differentially input to the amplifier circuit 22 and output signal differences are obtained. Amplified accordingly.

  As shown in FIG. 7B, in the detection of the detection target in the Y-axis direction, one Y-axis electrode 15b switched as the detection electrode is connected to the positive terminal of the amplifier circuit 22, and the other Y-axis electrode. 15 c is connected to the negative terminal of the amplifier circuit 22. The drive voltage is applied from the drive circuit 20 to the X-axis electrodes 14a to 14f switched as the drive electrodes, and the signals output from the Y-axis electrodes 15b and 15c are differentially input to the amplifier circuit 22 and the difference between the output signals is obtained. Amplified accordingly.

  FIGS. 8A and 8B are diagrams illustrating an example of electrode connection when the output signal of the detection electrode is single-ended input in the second detection mode. As shown in FIG. 8A, in the detection of the detection target in the X-axis direction, the X-axis electrode 14e switched as the detection electrode is connected to the positive terminal of the amplifier circuit 22. A reference voltage is input to the negative terminal of the amplifier circuit 22. A drive voltage is applied from the drive circuit 20 to the Y-axis electrodes 15a to 15f switched as the drive electrodes, and a signal output from the X-axis electrode 14e is single-ended input to the amplifier circuit 22 and corresponds to the difference from the reference voltage. Amplified.

  As shown in FIG. 8B, in the detection of the detection target in the Y-axis direction, the Y-axis electrode 15 b switched as the detection electrode is connected to the positive terminal of the amplifier circuit 22. A reference voltage is input to the negative terminal of the amplifier circuit 22. A drive voltage is applied from the drive circuit 20 to the X-axis electrodes 14a to 14f switched as the drive electrodes, and a signal output from the Y-axis electrode 15b as the detection electrode is single-ended input to the amplifier circuit 22, It is amplified according to the difference.

  Thus, in the present embodiment, one amplifier circuit 22 switches between the differential input and the single-ended input according to the detection method. For this reason, in the detection of the detection object in the X-axis direction and the Y-axis direction, the detection object position can be detected by the single end input even in the state where the difference value between the output signals of the pair of detection electrodes becomes the detection lower limit. Insensitive areas due to the amplification characteristics of the detection method can be complemented. Further, since the detected object position can be detected by differential input in both the first detection mode and the second detection mode, the influence of noise can be reduced and the circuit configuration of the control circuit unit 12 can be simplified. Can do.

  Next, the detection principle of the detection target in the X-axis direction and the Y-axis direction in the capacitive proximity sensor device according to the present embodiment will be described with reference to FIG. FIG. 9 is a conceptual diagram showing a detection principle in the capacitive proximity sensor device according to the present embodiment. In FIG. 9, the X-axis electrodes 14a to 14f switched as detection electrode pairs are shown as detection electrodes 14A and 14B, and the Y-axis electrodes 15a to 15f switched as drive electrodes are schematically shown as drive electrodes 15A and 15B. It shows.

FIG. 9 shows a case where the position of the detected body 41 is detected when the detected body 41 moves in the X-axis direction. As shown in FIG. 9, when detecting the position of the detected object 41 in the X-axis direction, the X-axis electrodes 14a to 14f are switched as detection electrodes 14A and 14B, and the Y-axis electrodes 15a to 15f are driven electrodes 15A and 15B. Is switched as In this case, between the detection electrode 14A and the detection electrode 15A and the detection electrodes 15B are formed capacitance _{C x1,} capacitance _{C x2} between the detection electrode 14B drive electrodes 15A and the drive electrodes 15B It is formed. And the position of the hand as the to-be-detected body 41 is detectable by using the output signal of the detection electrode according to this electrostatic capacitance _Cx1 , _Cx2 .

Furthermore, with reference to FIG.9 and FIG.10, the motion of the to-be-detected body 41 and the change of an electrostatic capacitance are demonstrated. FIG. 10 is a diagram illustrating a change in the difference in capacitance when the detection target 41 moves left and right in the example illustrated in FIG. 9. In the example shown in FIG. 9, the detection electrodes 14A and the drive electrodes 15A, 15B capacitance _{C x1} is formed between the detection electrodes 14B and drive electrodes 15A, the capacitance _{C x2} between 15B Is formed. When the detection object 41 moves in any direction of the X-axis direction (left-right direction), it is formed between the detection electrode 14A and the drive electrodes 15A and 15B and between the detection electrode 14B and the drive electrodes 15A and 15B. Electric lines of force (not shown) are absorbed by the detection object 41, and the capacitances C _x1 and C _x2 change. For example, when the detected object 41 moves to the left side, the capacitance C _x1 increases and the capacitance C _x2 decreases. For this reason, when the detected object 41 moves in the X-axis direction (left-right direction), the difference in capacitance value (C _x2 -C _x1 ) is taken to obtain the amount of change in capacitance as shown in FIG. In addition, it is possible to detect the position information and motion (motion) of the detected object 41 in the X-axis direction (left-right direction) of the detected object.

  When detecting the detection target 41 in the Y-axis direction, the drive electrodes 15A and 15B are used as detection electrodes, and the detection electrodes 14A and 14B are used as drive electrodes. Motion is detected. Therefore, in the capacitance type motion detection device including the capacitance type proximity sensor device according to the present invention, the position information of the detected object calculated by the calculation circuit of the capacitance type proximity sensor device is obtained at a predetermined time. By processing with a constant, it is possible to detect the motion of the detected object.

Next, with reference to FIGS. 11A and 11B, the detection principle of the detection target in the Z-axis direction of the capacitive proximity sensor according to the present embodiment will be described. FIGS. 11A and 11B are diagrams showing the detection principle of the detected object in the Z-axis direction of the capacitive proximity sensor according to the embodiment, and the sensor unit 11 shown in FIG. The AA arrow directional cross-sectional view of is shown typically. In the example shown in FIGS. 11A and 11B, a capacitance C _X3 is formed between the X-axis electrodes 14a to 14f and the Y-axis electrodes 15a to 15f, and electric lines of force 42 are formed around the capacitance C _X3. ing.

As shown in FIG. 11 (a), when the distance in the Z-axis direction between the sensor surface 13a of the sensor unit 11 and the detected body 41 is large, the absorption of the electric force lines 42 by the detected body 41 is one. Therefore, the capacitance C _X3 increases. On the other hand, as shown in FIG. 11 (b), when the distance between the sensor surface 13a and the detected body 41 is small, most of the electric lines of force 42 are absorbed by the detected body 41. The capacity C _X3 is reduced. For this reason, when the distance between the sensor surface 13a of the sensor unit 11 and the detection target 41 is small, the capacitance C _X3 decreases and the output signal of the detection electrode 14a increases, and the sensor surface 13a and the detection target 41 become large. When the distance to the detection body 41 is large, the capacitance C _X3 increases and the output signal of the detection electrode decreases. As described above, the position of the detection object 41 in the Z-axis direction can be detected.

  Next, with reference to FIGS. 12A and 12B, an output signal at the time of detection of the detection object in the first detection mode of the capacitive proximity sensor device will be described. FIG. 12A is a diagram illustrating a detection result of the detection target in the X-axis direction in the first detection mode, and FIG. 12B is a diagram of the detection target in the Y-axis direction in the first detection mode. It is a figure which shows a detection result.

  In FIG. 12A, the difference between the detected object position and the signal output from the detection electrode when the X-axis electrodes 14a and 14f are switched as the detection electrodes and the Y-axis electrodes 15a and 15f are switched as the drive electrodes. The relationship with the value is shown. As shown in FIG. 12A, when the detected object 41 moves horizontally in the X-axis direction with respect to the sensor surface 13a, the detected object is located near the X-axis electrode 14a connected to the negative terminal of the amplifier circuit 22. When the body 41 exists, the difference value becomes the minimum value. As the detected object 41 moves to the X-axis electrode 14f, the difference value increases. When the detected object 41 exists in the vicinity of the X-axis electrode 14f connected to the positive terminal of the amplifier circuit 22, the difference value is the maximum value. It becomes.

  In FIG. 12B, the difference between the detected object position and the signal output from the detection electrode when the Y-axis electrodes 15a and 15f are switched as the detection electrodes and the X-axis electrodes 14a and 14f are switched as the drive electrodes. The relationship with the value is shown. As shown in FIG. 12B, when the detected object 41 moves horizontally in the Y-axis direction with respect to the sensor surface 13a, the detected object is in the vicinity of the Y-axis electrode 15f connected to the negative terminal of the amplifier circuit 22. When the body 41 exists, the difference value becomes the minimum value. As the detected object 41 moves to the Y-axis electrode 15a, the difference value increases. When the detected object 41 exists in the vicinity of the Y-axis electrode 15a connected to the positive terminal of the amplifier circuit 22, the difference value is the maximum value. It becomes. Thus, in the capacitive proximity sensor device according to the present embodiment, the movement of the detection object can be detected by the change in the output signal value.

  Next, referring to FIG. 1 again, the overall operation of the capacitive proximity sensor device according to the present embodiment configured as described above will be described. First, the switching control circuit 18 switches the X-axis electrodes 14a to 14f and the Y-axis electrodes 15a to 15f as drive electrodes and detection electrodes according to the first detection mode and the second detection mode. Next, the drive voltage whose timing is controlled by the CPU 19 is applied to the X-axis electrodes 14a to 14f and 15a to 15f switched from the drive circuit 20 as drive electrodes.

  Signals output from the X-axis electrodes 14 a to 14 f and the Y-axis electrodes 15 a to 15 f as detection electrodes are input to the amplification circuit 22 of the detection circuit 21 and amplified. The output signal amplified by the amplifier circuit 22 is filtered and A / D converted by the A / D converter 23 and input to the CPU 19. The CPU 19 calculates the distance between the sensor surface 13a and the detected object and the position of the detected object on the sensor surface 13a based on the input output signal.

  Next, an application example of the electrostatic proximity sensor device will be described. The capacitive proximity sensor device according to this embodiment can be used for an input device of a portable device. In this case, the up / down / left / right movement of the operator's finger with respect to the sensor surface 13a detected in the first detection mode is set as the first input operation, and the operator's finger on the sensor surface 13a detected in the second detection mode is operated. The action can be identified as a different input operation as the second input operation. Therefore, for example, in a portable device, when an input operation is performed on a desired input button from a selection list displayed on one screen, the desired operation is performed from the search list by the movement of the upper, lower, left, and right fingers on the sensor surface 13a. The input button is selected (first input operation). When an input operation is performed on a desired input button, the approach of the operator's finger on the surface of the display device as the sensor surface 13a is detected (second input operation), and the finger on the sensor surface 13a is detected. By enlarging and displaying a desired input button in accordance with the approaching operation, an input operation by a touch operation can be facilitated. With this configuration, even if the area of the display device of the input device is reduced, an input operation with an operator's finger can be easily performed on a desired input button from the selection list. It becomes possible to reduce the size.

  In the above embodiment, an example in which the electrodes at both ends of the six X-axis electrodes 14a to 14f and the six Y-axis electrodes 15a to 15f are switched as detection electrodes to detect the approach of the detection object to the sensor surface 13a. However, for example, as shown in FIG. 13, the sensor unit may be configured by eight X-axis electrodes 14 a to 14 h and eight Y-axis electrodes 15 a to 15 h. In this case, in the first detection mode, the sensor surface 13a is divided into four detection target areas A1 to A4, and the X-axis electrodes 14a to 14f and Y at both ends of each detection target area A1 to A4. The object to be detected is measured four times for each of the X-axis direction and the Y-axis direction so that the shaft electrodes 15a to 15f become detection electrodes or drive electrodes, and the addition average is calculated to calculate the position of the detection object May be detected.

  For example, as shown in FIG. 13, in the detection of the detection target in the X-axis direction in the first detection mode, detection is performed by switching the X-axis electrodes 14a and 14d as detection electrodes and the Y-axis electrodes 15a and 15d as drive electrodes. The target area A1 is detected. Next, the detection target region A2 is detected by switching the X-axis electrodes 14e and 14h as detection electrodes and the Y-axis electrodes 15a and 15d as drive electrodes. Next, the detection target region A3 is detected by switching the X-axis electrodes 14a and 14d as detection electrodes and the Y-axis electrodes 15e and 15h as drive electrodes. Next, the detection target region A4 is detected by switching the X-axis electrodes 14e and 14h as detection electrodes and the Y-axis electrodes 15e and 15h as drive electrodes. By detecting in this way, the detection accuracy (resolution) with respect to the X-axis direction and the Y-axis direction of the sensor surface 13a can be improved.

  As described above, in the capacitive proximity sensor device according to the present embodiment, the X-axis electrodes 14a to 14f and the Y-axis electrodes 15a to 15f are arranged in a matrix. Then, the first detection using the X-axis electrodes 14a and 14f (Y-axis electrodes 15a and 15f) arranged apart from each other as drive electrodes and the Y-axis electrodes 15a and 15f (X-axis electrodes 14a and 14f) as detection electrodes is performed. Depending on the mode, a signal corresponding to the capacitance formed between the electrodes arranged apart from each other is output, so that the output signal increases and the approach of the detection target to the sensor surface 13a can be detected. The Y-axis electrodes 15a to 15f (X-axis electrodes 14a to 14f) are used as drive electrodes, the adjacent X-axis electrodes 14a to 14f (Y-axis electrodes 15a to 15f) are used as detection electrodes, and the electrodes serving as detection electrodes are used as the X-axis. The detected object on the sensor surface 13a can be detected by the second detection mode that is sequentially switched within the electrodes 14a to 14f and the Y-axis electrodes 15a to 15f.

  In addition, this invention is not limited to the said embodiment, It can change and implement variously. In the above-described embodiment, the size, shape, and the like illustrated in the accompanying drawings are not limited to this, and can be appropriately changed within a range in which the effect of the present invention is exhibited. In addition, various modifications can be made without departing from the scope of the object of the present invention.

  For example, in the capacitive proximity sensor device according to the above-described embodiment, the configuration in which the plurality of X-axis electrodes 14a to 14f and the plurality of Y-axis electrodes 15a to 15f are arranged in a matrix has been described. The number and arrangement of the Y-axis electrodes can be changed in a timely manner as long as they are within a range in which the detection target can be detected on the sensor surface 13a and the proximity of the detection target to the sensor surface 13a. For example, the X-axis electrodes 14a to 14f and the Y-axis electrodes 15a to 15f may be arranged at an arbitrary angle. Furthermore, the X-axis electrodes 14a to 14f and the Y-axis electrodes 15a to 15f do not necessarily need to be arranged on the same plane as long as the detection target can be detected by the capacitance formed between the electrodes.

  In the capacitive proximity sensor device according to the above-described embodiment, the electrode to be switched as the detection electrode or the drive electrode in the detection of the detection object in the X-axis direction and the Y-axis direction in the first detection mode is detected. Any combination that can detect the distance between the body and the sensor surface can be changed in a timely manner. For example, the X-axis electrodes 14b and 14e arranged as separated as the detection electrode or the drive electrode may be switched as the detection electrode or the drive electrode.

  Furthermore, in the capacitive proximity sensor device according to the above-described embodiment, the electrodes used as the end electrodes in the detection of the detection target in the Z-axis direction in the first detection mode are the sensor surface 13a and the detection target. Any combination that can detect the distance between can be changed in a timely manner. For example, the X-axis electrodes 14b and 14e and the Y-axis electrodes 15b and 15e may be used as end electrodes. Similarly, in the example shown in FIG. 13, the electrodes to be switched as detection electrodes or drive electrodes are not limited to both ends in the X-axis direction and both ends in the Y-axis direction of each detection target region A1 to A4, and can be changed as appropriate. is there.

  In the capacitive proximity sensor device according to the above embodiment, one or two electrodes from the X-axis electrodes 14a to 14f and the Y-axis electrodes 15a to 15f are used in the first detection mode and the second detection mode. Although an example of switching as a drive electrode or a detection electrode has been described, a larger number of electrodes may be switched together as a drive electrode or a detection electrode. In this case, since the electric lines of force 42 formed on the sensor surface 13a increase, the detection sensitivity of the detected object approaching the sensor surface 13a can be further increased.

  INDUSTRIAL APPLICABILITY The present invention has an effect that it can detect the distance between the object to be detected and can accurately detect the touch position by the object to be detected. In particular, the portable device, digital photo frame, PC, audio operation panel, etc. It can be applied to various input devices.

DESCRIPTION OF SYMBOLS 11 Sensor part 12 Control circuit part 13 Board | substrate 14a-14f X-axis electrode 15a-15f Y-axis electrode 14A, 14B Detection electrode 15A, 15B Drive electrode 16 X-axis multiplexer 17 Y-axis multiplexer 18 Switching control circuit 19 CPU
DESCRIPTION OF SYMBOLS 20 Drive circuit 21 Detection circuit 22 Amplification circuit 23 A / D converter 31 Glass substrate 32 Protection board 41 Detected object 42 Electric field line

Claims (8)

A plurality of X-axis electrodes arranged in the X-axis direction;
A plurality of Y-axis electrodes arranged at an arbitrary angle so as to form a capacitance between the plurality of X-axis electrodes;
A drive circuit for outputting a drive voltage to be applied to an electrode serving as a drive electrode among the plurality of X-axis electrodes and the plurality of Y-axis electrodes;
A detection circuit for detecting a signal output from an electrode serving as a detection electrode among the plurality of X-axis electrodes and the plurality of Y-axis electrodes;
Calculation means for calculating the detected object position in the X-axis direction, the Y-axis direction, and the Z-axis direction with respect to the detection reference plane from the detection result of the detection circuit;
Among the plurality of X-axis electrodes and the plurality of Y-axis electrodes, there is provided switching means for connecting an electrode serving as the drive electrode to the drive circuit and connecting an electrode serving as the detection electrode to the detection circuit. ,
The switching means connects at least two X-axis electrodes arranged apart from each other to the detection circuit as the detection electrodes, and uses at least two Y-axis electrodes arranged apart from each other as the drive electrodes. A first detection mode connected to the drive circuit;
At least one of the Y-axis electrodes is connected to the drive circuit as the drive electrode, and at least two adjacent X-axis electrodes are connected to the detection circuit as the detection electrodes, and an electrode to be the detection electrode is connected to the detection circuit. A capacitive proximity sensor device that switches between a second detection mode that is sequentially switched within an X-axis electrode.   In the first detection mode, the switching means connects at least two of the X-axis electrodes arranged apart from each other to the detection circuit as the detection electrodes, and at least two Y arranged apart from each other. An electrode pattern connecting the shaft electrode as the drive electrode to the drive circuit and at least two Y-axis electrodes arranged apart from each other are connected to the detection circuit as the detection electrodes, and at least arranged apart from each other 2. The capacitive proximity sensor device according to claim 1, wherein an electrode pattern that connects the two X-axis electrodes as the drive electrodes to the drive circuit is switched.   In the first detection mode, the switching means includes the X-axis electrode at one end in the X-axis direction, the X-axis electrode at the other end, and the Y-axis electrode at one end in the Y-axis direction, And at least one of the end electrodes including the Y-axis electrode at the other end is connected to the detection circuit as the detection electrode, and at least one of the end electrodes is connected to the drive electrode. 3. The capacitive proximity sensor device according to claim 1, wherein the capacitance proximity sensor device is connected to the driving circuit and sequentially switches the electrodes to be the detection electrodes in the end electrodes.   In the second detection mode, the switching unit connects at least one of the Y-axis electrodes as the drive electrode, and connects at least two adjacent X-axis electrodes as the detection electrodes together with the detection circuit, An electrode pattern for sequentially switching the electrodes to be the detection electrodes within the X-axis electrode, and at least one X-axis electrode as the drive electrode is connected to the drive circuit, and at least two adjacent Y-axis electrodes are The static electrode according to any one of claims 1 to 3, wherein both the detection electrodes are connected to the detection circuit, and an electrode pattern for sequentially switching the electrodes to be the detection electrodes within the Y-axis electrode is switched. Capacitive proximity sensor device.   In the first detection mode, the switching unit divides the inside of the detection reference plane into at least two detection target regions, and sets the X-axis electrodes positioned at both ends in the X-axis direction of the detection target regions. The driving electrode is connected to the driving circuit, and the Y-axis electrodes located at both ends in the Y-axis direction are connected to the detection circuit as the detection electrodes, and the computing means is applied to each detection target region. 5. The capacitive proximity sensor device according to claim 1, wherein the position of the detection body is calculated.   In the first detection mode, the switching unit divides the detection reference plane into at least two detection target regions, and the Y-axis electrodes positioned at both ends in the Y-axis direction of each detection target region are The drive circuit is connected to the drive circuit, and the X-axis electrodes located at both ends in the X-axis direction are connected to the detection circuit as the detection electrodes. 6. The capacitive proximity sensor device according to claim 1, wherein the detection body position is calculated.   The detection circuit includes a differential amplifier circuit having a positive electrode terminal and a negative electrode terminal, inputs an output signal of one detection electrode switched in the first detection mode to a positive electrode terminal, and outputs an output signal of the other detection electrode Is input to the negative electrode terminal, the output signal of one detection electrode switched in the second detection mode is input to the positive electrode terminal, and the output signal of the other detection electrode is input to the negative electrode terminal. The capacitive proximity sensor device according to any one of claims 1 to 6.   The capacitive proximity sensor device according to any one of claims 1 to 7, and the position information of the detected object calculated by the calculation circuit are processed with a predetermined time constant, and the motion of the detected object is detected. A capacitive motion detection device comprising: motion detection means for performing detection.

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