Source: https://patents.google.com/patent/JP2015099462A/en
Timestamp: 2019-12-06 07:50:07
Document Index: 11194721

Matched Legal Cases: ['art 2', 'art. 2', 'art 2', 'art 2', 'art 4', 'art 4', 'art 45', 'art 45', 'art 8', 'art 4', 'art 1', 'art 2', 'art 3', 'art 6', 'art 8', 'art 10', 'art 12']

JP2015099462A - Coordinate input device and mobile terminal - Google Patents
JP2015099462A
JP2015099462A JP2013238498A JP2013238498A JP2015099462A JP 2015099462 A JP2015099462 A JP 2015099462A JP 2013238498 A JP2013238498 A JP 2013238498A JP 2013238498 A JP2013238498 A JP 2013238498A JP 2015099462 A JP2015099462 A JP 2015099462A
JP2013238498A
2013-11-19 Application filed by ルネサスエレクトロニクス株式会社, Renesas Electronics Corp filed Critical ルネサスエレクトロニクス株式会社
2015-05-28 Publication of JP2015099462A publication Critical patent/JP2015099462A/en
PROBLEM TO BE SOLVED: To provide a coordinate input device configured to detect a position of a distant conductor.SOLUTION: A coordinate input device 100 includes a signal generation section 1, a transmission antenna section 2, a receiving antenna 3, and a detection section 4. The transmission antenna section 2 includes a plurality of antennas for transmitting electromagnetic waves S according to an AC signal SIG. The signal generation section 1 outputs an AC signal SIG to any of the plural antennas of the transmission antenna section 2. The receiving antenna 3 receives the electromagnetic wave W from the transmission antenna section 2. The detection section 4 acquires an intensity distribution of the electromagnetic waves W corresponding to positions of the plural antennas, on the basis of the electromagnetic wave W received by the receiving antenna 3, to detect a detection position according to a peak position of the intensity distribution.
The present invention relates to a coordinate input device and a portable terminal, for example, a coordinate input device incorporated in a touch panel and a portable terminal equipped with the touch panel.
In mobile devices such as smartphones and tablet PCs that have rapidly spread in recent years, a coordinate input device such as a touch panel is used as an input interface instead of a keyboard and a mouse. The touch panel has a display function and an input function, and can realize an input interface that is easier to understand and intuitive than a keyboard or mouse. Various methods have been proposed as a method for realizing a touch panel. Of these, the mainstream systems are the resistance film type (Patent Document 1) and the capacitance type (Patent Document 2).
FIG. 44 is a configuration diagram showing an example of a general resistive film type touch panel 800. In the touch panel 800, a large number of dot-like protrusions 802 are formed on the surface of the transparent resistance sheet 801 having a uniform sheet resistance. The transparent resistance sheet 801 and the transparent electrode sheet 803 are overlapped, and the protrusion 802 is a spacer that electrically separates the transparent resistance sheet 801 and the transparent electrode sheet 803. Diode groups 808 to 811 are connected to the four sides 804 to 807 of the transparent resistance sheet 801, respectively. The switch 813 is a two-pole double-throw switch for polarity switching. When the a side of the switch 813 is closed, the current flows from the positive electrode of the power source 812 to the loop from the positive electrode of the power source 12 through the switch 813, the diode group 810, the transparent resistance sheet 801, the diode group 811, and the switch 813. . For this reason, equipotential lines substantially parallel to the sides 806 and 807 are generated in the transparent resistance sheet 801. When the b side of the switch 813 is closed, the current flows from the positive electrode of the power supply 812 to the loop that passes through the switch 813, the diode group 808, the transparent resistance sheet 801, the diode group 809, and the switch 813 to the negative electrode of the power supply 12. For this reason, equipotential lines substantially parallel to the sides 804 and 805 are generated in the transparent resistance sheet 801. When a point 815 on the transparent electrode sheet 803 is pressed with the side 814 from the top of the transparent electrode sheet 803, the transparent resistance sheet 801 and the transparent electrode sheet 803 are converted into a point 815 and a point 816 on the transparent resistance sheet 801 corresponding to this point. Contact with. Accordingly, the potential at the point 816 is transmitted to the transparent electrode sheet 803. Since the potential of the point 816 corresponds to the coordinate of the point 816, when the potential of the point 816 is detected by the detection circuit 817, the coordinate of the pressed point is identified. The potential of the point 816 corresponds to the y coordinate when the a side of the switch 813 is closed, and to the x coordinate when the b side is closed. Therefore, by switching the switch 813, both the x and y coordinates of the point 815 can be identified.
As described above, in the resistance film type (Patent Document 1), it is necessary to press the resistance film and to deform it by pressing the resistance film. Therefore, a flexible material is required for the material used for the resistance film. Therefore, the touch panel surface is easily damaged and the durability is inferior. Further, when a plurality of locations on the resistance film are pressed with a finger, the measured resistance value is substantially the same as when one location close to the resistance measurement point is pressed among the plurality of locations. Therefore, a plurality of fingers cannot be detected simultaneously.
FIG. 45 is a configuration diagram showing an example of a general electrostatic capacitance type touch panel system 900. As shown in FIG. 45, the touch panel system 900 includes a touch panel 910 and a touch panel controller 920. The touch panel 910 includes a sensor 911 that inputs a signal when the user performs a touch operation. The touch panel controller 920 includes an input terminal that receives a signal from the sensor 911, a coordinate detection unit 921 that outputs a coordinate value based on a signal input to the input terminal, and coordinate information from the coordinate detection unit 921 at regular intervals. The CPU 922 performs fetching, outputting to a display device, and the like. The coordinate detection unit 921 includes a touch operation sensitivity changing unit 923 that changes the sensitivity of the touch operation.
The sensor 911 is a capacitive sensor, and when the user touches the touch panel 910, the electrodes constituting the sensor 911 detect a change in the capacitance value between the drive line and the sense line shown in FIG.
The touch panel 910 includes M drive lines DL and L sense lines SL, and configures a capacitive sensor 911 at the intersection. In the coordinate detection operation of the touch operation, the coordinates of the touch-operated part are detected by reading the change in the capacitance value of the sensor by the touch operation with the sense line SL while scanning the drive line DL. At this time, considering the case where the detected change value of the capacitance value is small, the reading operation is performed a plurality of times, and the signal value is obtained by integrating the received signal from the touch panel a plurality of times corresponding to the plurality of reading operations. An increase operation is being performed.
As described above, since the capacitance type (Patent Document 2) does not require deformation of the film, a hard material can be used for the touch panel surface. Therefore, it is more durable than the resistance film type. Further, in this method, the capacitance can be measured for each intersecting portion of the vertical and horizontal electrodes, so that each position of the plurality of fingers can be detected even if the finger touches a plurality of positions on the touch panel.
JP 59-85584 A JP 2012-248035 A
However, the inventor has found that the position detection using the touch panel has the following problems. In the capacitance type described above, when the capacitance between the finger and the electrode is smaller than the capacitance between the vertical electrode and the horizontal electrode, the accuracy of capacitance measurement is lowered. For this reason, when the finger is removed from the touch panel, the position of the finger cannot be detected. For example, in the capacitance type, when a glove is worn, the finger is separated from the touch panel by the thickness of the glove, so that the position of the finger cannot be detected.
According to an embodiment, the coordinate input device includes a signal generation unit that outputs an AC signal, a first transmission / reception unit that includes a plurality of first antennas that transmit and receive a signal corresponding to the AC signal, A second transmitting / receiving unit having a second antenna for transmitting / receiving the signal to / from the transmitting / receiving unit, and a position of the plurality of first antennas when the first transmitting / receiving unit transmits / receives the signal A detection unit that acquires an intensity distribution of the signal and detects a detection position according to a peak position of the intensity distribution.
According to an embodiment, the coordinate input device is a coordinate input device that detects a position of a conductor, and a signal generator that outputs an AC signal, and a plurality of second transmitters that transmit and receive a signal corresponding to the AC signal. A first transmission / reception unit having one antenna, a second transmission / reception unit having a second antenna for transmitting / receiving the signal between the first transmission / reception unit, and the first transmission / reception unit transmitting / receiving the signal. And obtaining the intensity distribution of the signal corresponding to the position of the plurality of first antennas, and according to the position of the peak of the intensity distribution, the plurality of first antennas of the first transceiver A detection unit that detects a position of the conductor inserted between the one or more second antennas of the second transmission / reception unit.
According to the one embodiment, in the coordinate input device, the position of the conductor at a distant position can be detected.
1 is a diagram schematically illustrating a configuration of a coordinate input device 100 according to a first embodiment. FIG. 2 is a diagram schematically illustrating the configuration of a signal generation unit 1 and a transmission antenna unit 2. 3 is a block diagram schematically showing a configuration of a detection unit 4. FIG. It is a figure which shows typically the structure of the coordinate input device 100 in case a conductor is inserted between the transmission antenna part 2 and the receiving antenna 3. FIG. It is a perspective view which shows an example at the time of seeing the portable terminal 101 with which the touchscreen which mounted the coordinate input device 100 is mounted from the touchscreen side (front side). It is a perspective view which shows an example at the time of seeing the portable terminal 101 with which the touchscreen carrying the coordinate input device 100 is mounted from the side (back side) opposite to the touch panel side (front side). FIG. 3 is a diagram illustrating an example when a user of the mobile terminal 101 holds the mobile terminal 101. 3 is a circuit configuration diagram showing an outline of position detection of a capacitive touch panel 103. FIG. 3 is a circuit configuration diagram showing an outline of position detection of the coordinate input device 100. FIG. It is a figure which shows the intensity | strength of the received signal concerning antenna line X1-X5. It is a figure which shows the intensity | strength of the received signal concerning antenna line Y1-Y5. 5 is a graph showing distance dependency of position detection in the coordinate input device 100. It is a figure which shows the intensity | strength of the received signal concerning antenna wire X1-X5 in Embodiment 2. FIG. FIG. 10 is a diagram illustrating the strength of reception signals applied to antenna lines X1 to X5 in the third embodiment. It is a figure which shows typically the electric field in the cross section of the antenna line X1 of a linear transmission antenna part. 2 is a diagram schematically showing an electric field in a cross section of a planar receiving antenna 3. FIG. FIG. 10 is a diagram schematically illustrating a configuration of a coordinate input device 500 according to a fifth embodiment. FIG. 3 is a diagram schematically showing configurations of a signal generation unit 5 and a transmission antenna unit 2. It is a figure which shows typically the breadth of electromagnetic waves at the time of seeing antenna line X1 from a cross-sectional direction. FIG. 10 is a diagram schematically illustrating a configuration of a coordinate input device 600 according to a sixth embodiment. It is a perspective view which shows an example at the time of seeing the portable terminal 601 with which the touchscreen which mounted the coordinate input device 600 is mounted from the touchscreen side (front side). It is a perspective view which shows an example at the time of seeing the portable terminal 601 with which the touchscreen carrying the coordinate input device 600 is mounted from the side (back side) opposite to the touchscreen side (front side). It is a figure which shows the switching timing of the receiving antennas 61-63. FIG. 10 is a diagram schematically illustrating a configuration of a coordinate input device 700 according to a seventh embodiment. It is a perspective view which shows an example at the time of seeing the portable terminal 701 with which the touchscreen which mounted the coordinate input device 700 is mounted from the touchscreen side (front side). It is a figure which shows the corresponding | compatible relationship between the receiving antennas 71 and 72 and an antenna line. It is a figure which shows the corresponding | compatible relationship between the receiving antennas 73 and 74 and an antenna line. It is a perspective view which shows an example at the time of seeing from the touch panel side (front side) the portable terminal 707 with which the touchscreen which mounted the coordinate input device which is a modification of the coordinate input device 700 is mounted. FIG. 20 is a diagram illustrating the strength of reception signals applied to antenna lines X1 to X5 in the eighth embodiment. FIG. 10 is a diagram illustrating the strength of reception signals applied to antenna lines Y1 to Y5 in the eighth embodiment. It is a figure which shows typically the structure of the coordinate input device 900 concerning Embodiment 9. FIG. It is a figure which shows the position detection of the coordinate input device 900 when the distance of the finger | toe 10 and the transmission antenna part 2 is small. 5 is a flowchart showing the operation of the coordinate input device 900. It is a figure which shows typically the structure of the coordinate input device 1000 concerning Embodiment 10. FIG. It is a figure which shows the connection of the coordinate input device 1000 in the case of detecting the position of the finger | toe 10 by an electrostatic capacitance type. It is a figure which shows the connection of the coordinate input device 1000 in the case of detecting the position of a finger | toe when the finger | toe 10 and the transmission antenna part 2 are separated. 5 is a flowchart showing the operation of the coordinate input device 1000. It is a figure which shows typically the structure of the coordinate input device 1100 concerning Embodiment 11. FIG. FIG. 3 is a diagram schematically showing a configuration of a signal generation unit 7. 3 is a diagram schematically showing a configuration of a detection unit 8. FIG. It is a figure which shows the frequency spectrum of noise when changing the frequency of a carrier wave and an alternating current signal. FIG. 23 is a diagram schematically illustrating position detection by the coordinate input device according to the twelfth embodiment; It is a figure which shows the example of the waveform of the low frequency component taken out from the received signal. It is a block diagram which shows the example of the general resistive film type touch panel 800. FIG. 1 is a configuration diagram illustrating an example of a general capacitive touch panel system 900. FIG.
Embodiments of the present invention will be described below with reference to the drawings. In the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted as necessary.
First, the coordinate input device 100 according to the first embodiment will be described. FIG. 1 is a diagram schematically illustrating the configuration of the coordinate input device 100 according to the first embodiment. The coordinate input device 100 includes a signal generation unit 1, a transmission antenna unit 2, a reception antenna 3, and a detection unit 4. The transmitting antenna unit 2 and the receiving antenna 3 are arranged spatially separated. The transmission antenna unit is also simply referred to as a first transmission / reception unit. The reception antenna is also simply referred to as a second transmission / reception unit.
The signal generation unit 1 supplies an AC signal SIG to the transmission antenna unit 2. As will be described in detail later, the transmission antenna unit 2 has a plurality of antenna lines arranged in a mesh. The signal generation unit 1 inputs the AC signal SIG to any one of the plurality of antenna lines of the transmission antenna unit 2. As a result, an electromagnetic wave W (radio wave) that is a signal for transmitting the AC signal SIG is radiated from any one of the plurality of antenna wires of the transmission antenna unit 2. The antenna line is also simply referred to as an antenna.
The reception antenna 3 receives the signal radiated from the transmission antenna unit 2. The reception antenna 3 outputs the received signal to the detection unit 4 as a reception signal RS1. An electromagnetic wave having a sufficiently long wavelength with respect to the size of the receiving antenna 3 is used as the electromagnetic wave W that is a signal for transmitting the AC signal SIG. For example, the wavelength of the electromagnetic wave W is desirably 10 times or more the size of the transmitting antenna unit 2 and the receiving antenna 3. That is, an electromagnetic wave having a frequency lower than the resonance frequency of the receiving antenna 3 is used. For example, in the case of an electromagnetic wave having a frequency of about 1 to 10 MHz, the wavelength is 300 to 30 m. For this reason, a typical mobile terminal having a size of about 10 inches is sufficiently smaller than the wavelength of electromagnetic waves. In this case, signal transmission by electromagnetic waves is performed by near-field electromagnetic waves, not by the far-field used in normal radio. Communication in the near field has a greater signal distance dependency than communication in the far field, so distance determination can be easily performed.
The detection unit 4 outputs a control signal CON1 to the signal generation unit 1 and controls which antenna line of the transmission antenna unit 2 the AC signal SIG is supplied to by the signal generation unit 1. And the detection part 4 detects the intensity | strength of the signal which the receiving antenna 3 received, and associates each antenna line with the intensity | strength of a received signal. The detection unit 4 can detect the intensity of the reception signal for each of the transmission antenna units 2 by switching the antenna line to which the AC signal SIG is supplied at a predetermined time interval by the control signal CON1.
The signal generation unit 1 and the transmission antenna unit 2 will be described in detail. FIG. 2 is a diagram schematically illustrating the configuration of the signal generation unit 1 and the transmission antenna unit 2. The signal generation unit 1 includes a signal oscillation unit 11, an amplifier 12, and a multiplexer (hereinafter referred to as “MUX”) 13. The signal oscillating unit 11 oscillates an AC signal SIG and inputs it to the amplifier 12. The amplifier amplifies the AC signal SIG and outputs it to the MUX 13.
The transmission antenna unit 2 includes antenna lines X1 to X5 extending in the Y direction and antenna lines Y1 to Y5 extending in the X direction. In FIG. 2, the X direction and the Y direction are orthogonal to each other. The antenna lines X1 to X5 are arranged below the antenna lines Y1 to Y5. Although FIG. 2 shows the case where there are five antenna lines in the X direction and Y direction, this is merely an example. An arbitrary number of antenna lines in the X direction and the Y direction can be provided, and the number of antenna lines in the X direction and the number of antenna lines in the Y direction may be different or the same. The Y-direction antenna line may be disposed below or above the X-direction antenna line.
The MUX 13 includes terminals T X1 to T X5 , terminals T Y1 to T Y5 , and a terminal Ts. The terminal Ts is connected to the output terminal of the amplifier 12. The multiplexer terminals T X1 to T X5 and T Y1 to T Y5 are connected to the antenna lines X1 to X5 and the antenna lines Y1 to Y5 , respectively. The MUX 13 connects the terminal Ts to any of the terminals T X1 to T X5 and T Y1 to T Y5 in accordance with the control signal CON1 from the detection unit 4.
The detection unit 4 will be described in detail. FIG. 3 is a block diagram schematically showing the configuration of the detection unit 4. The detection unit 4 includes an amplifier 41, a filter 42, a detection unit 43, an A / D converter 44, and a position detection unit 45. The amplifier 41 amplifies the reception signal RS1 from the reception antenna 3 and outputs the amplified signal to the filter 42. The filter 42 outputs the reception signal RS2 obtained by removing unnecessary frequency components such as noise from the reception signal RS1 to the detection unit 43. The detection unit 43 detects the amplitude, frequency shift, and phase shift of the specific frequency component of the AC signal of the reception signal RS <b> 2 and outputs a corresponding voltage to the A / D converter 44. The A / D converter 44 performs A / D conversion on the reception signal RS3 that is an analog signal, and outputs the reception signal RSd that is a digital signal to the position detection unit 45. As a result, the intensity of the received signal is digitized, and the position detection unit 45 can quantitatively evaluate the intensity of the received signal. In other words, the intensity of the electromagnetic wave W can be detected by converting the electromagnetic wave W received by the receiving antenna 3 into a received signal such as voltage or current. The position detection unit 45 can select an antenna line that transmits the electromagnetic wave W by the control signal CON1, and can detect the intensity of the received signal at that time and associate it with the antenna line. The position information POS detected by the position detection unit 45 is appropriately output to an external computer or the like.
In the coordinate input device 100, the AC signal SIG is spatially transmitted by the electromagnetic wave W between the transmission antenna unit 2 and the reception antenna 3. At this time, if a conductor is inserted between the transmitting antenna unit 2 and the receiving antenna 3, the intensity of the signal received by the receiving antenna 3 changes. FIG. 4 is a diagram schematically illustrating the configuration of the coordinate input device 100 when a conductor is inserted between the transmission antenna unit 2 and the reception antenna 3. FIG. 4 shows an example in which the user's finger 10 of the coordinate input device 100 is inserted as an example of the conductor. When the finger 10 is inserted between the transmission antenna unit 2 and the reception antenna 3, the signal intensity changes as compared to the case where the finger 10 is not inserted. Therefore, the presence or absence of the finger 10 between the transmission antenna unit 2 and the reception antenna 3 can be detected by detecting a change in signal strength by the detection unit 4. Thereby, the detection unit 4 can detect the position of the finger 10 with respect to the transmission antenna unit 2.
1 and 4, the transmission antenna 2 and the reception antenna 3 have been described. However, the transmission antenna 2 can be used as a reception antenna, and the reception antenna can be used as a transmission antenna. In this case, the detection unit 4 shown in FIG. 3 is connected to the terminal TS shown in FIG. 2 instead of the signal oscillation unit 11 and the amplifier 12. Further, the signal oscillating unit 11 and the amplifier 12 are connected to the receiving antenna 3. Further, in FIG. 2, the antenna lines are two sets of the orthogonal X direction and Y direction, but this is merely an example. For example, a set of antenna lines in different directions such as a Z direction orthogonal to the X direction and the Y direction can be arranged.
Next, an implementation mode of the coordinate input device 100 will be described. FIG. 5 is a perspective view illustrating an example when the mobile terminal 101 on which the touch panel on which the coordinate input device 100 is mounted is mounted is viewed from the touch panel side (front side). The mobile terminal 101 is a smartphone, for example. A touch panel 103 is mounted on the front side of the casing 102 of the mobile terminal 101. The transmission antenna unit 2 is incorporated in the touch panel 103. The plurality of mesh-like antenna lines provided in the transmission antenna unit 2 function as a transmission antenna of the coordinate input device 100 and also function as an electrode of a so-called capacitive touch panel 103.
FIG. 6 is a perspective view showing an example when the portable terminal 101 on which the touch panel on which the coordinate input device 100 is mounted is mounted is viewed from the side (back side) opposite to the touch panel side (front side). On the back side of the casing 102 of the portable terminal 101, the receiving antenna 3 is arranged. The receiving antenna 3 may be disposed outside the housing 102 or may be disposed inside the housing 102. That is, the receiving antenna 3 may be touched by a finger or may not be touched by the finger. Hereinafter, the present invention is not limited to this example, and a finger may or may not touch the receiving antenna. The signal generation unit 1 and the detection unit 4 are arranged inside the housing 102 of the mobile terminal 101.
As described above, when the coordinate input device 100 is incorporated in the mobile terminal 101, the user of the mobile terminal 101 operates the mobile terminal 101 by touching the touch panel 103 with a finger. FIG. 7 is a diagram illustrating an example when the user of the mobile terminal 101 holds the mobile terminal 101. As shown in FIG. 7, the user holds the portable terminal 101 with the left hand 10a, for example. At this time, some fingers of the left hand 10a come into contact with the back side (receiving antenna 3 side) of the portable terminal 101. Further, in order to operate the mobile terminal 101, the user moves a part of the finger of the left hand 10a or the finger 10 of the right hand 10b above the touch panel. When moving a part of the finger of the left hand 10a, the electromagnetic wave W is transmitted from the finger above the touch panel 103 through the finger on the receiving antenna 3 side. When the finger 10 is moved, the electromagnetic wave W is transmitted from the finger 10 via the human body (path L shown in FIG. 7) and the finger of the left hand 10a.
On the other hand, the user's finger acts as a kind of conductor for the coordinate input device 100. At this time, the position of the finger relative to the transmission antenna unit 2 can be detected by the function of the coordinate input device 100 regardless of whether the user's finger is in contact with or away from the touch panel 103. The principle that the coordinate input device 100 detects the position of the finger when the user's finger is away from the touch panel 103 will be described later.
Next, the difference between the position detection of the capacitive touch panel and the position detection of the coordinate input device 100 will be described. First, a method for detecting the position of a capacitive touch panel will be described. FIG. 8 is a circuit configuration diagram showing an outline of position detection of the capacitive touch panel 103. In FIG. 8, electrodes E11 and E12, a signal generator 1, and an ammeter AMM are included. The electrode E11 corresponds to any one of the antenna lines X1 to X5 of the transmission antenna unit 2. The electrode E12 corresponds to one of the antenna lines Y1 to Y5 of the transmission antenna unit 2.
A signal is input to the electrode E11 from the oscillator S1. An ammeter AMM is connected to the electrode E12. A capacitance C11 is generated between the electrode E11 and the electrode E12. When the finger 10 approaches the electrodes E11 and E12 in a state where a signal is input from the oscillator S1 to the electrode E11, a capacitance C12 is generated between the electrode E11 and the finger, and a capacitance C13 is generated between the electrode E12 and the finger. .
The combined capacitance C t1 by the capacitances C11, C12, and C13 is expressed by the following formula (1).
When the finger 10 moves away from the electrodes E11 and E12, the capacitors C12 and C13 become smaller than the capacitor C11, and thus the sensitivity of the capacitance detection with respect to the change in the position of the finger 10 is lowered. That is, in the capacitance type, if the finger 10 is separated from the electrodes E11 and E12, the position of the finger 10 cannot be detected. For this reason, many electrostatic capacitance type touch panels need to touch the touch panel with a finger. In order to increase the sensitivity when the finger is moved away from the capacitive touch panel, the capacitance C11 may be reduced by increasing the distance between the electrode E11 and the electrode E12. However, in this case, the distance between the electrode E11 and the electrode E12 is widened, so that the position detection resolution is lowered.
Next, position detection of the coordinate input device 100 will be described. FIG. 9 is a circuit configuration diagram showing an outline of position detection of the coordinate input device 100. In FIG. 9, only the antenna lines X1 and X2 among the antenna lines of the transmission antenna unit 2 are illustrated for simplification. The AC signal SIG is selectively input from the signal generator 1 to each of the antenna lines X1 and X2. In this example, for simplification of description, the case where the AC signal SIG is input to the antenna line X1 will be described, but the antenna line to which the AC signal SIG is supplied is not limited to the antenna line X1. A capacitor C21 is generated between the antenna line X1 and the antenna line X2. When a finger 10 and a finger 11 are inserted between the antenna line X1 and the receiving antenna 3 in a state where a signal is input from the signal generator 1 to the antenna line X1, a capacitance is generated between the antenna line X1 and the finger 10. C22 is generated, and a capacitance C23 is generated between the finger 10 and the receiving antenna 3. A capacitor C24 exists between the antenna line X1 and the receiving antenna 3. Here, the finger 10 and the finger 11 may be fingers that are electrically connected, and may be the same finger or different fingers. It is assumed that the finger 10 is in the vicinity of the antenna line X1 and the finger 11 is in the vicinity of the receiving antenna 3.
In this position detection method, a signal from the transmission antenna unit 2 is sent to the reception antenna via the finger 10 and the finger 11. In this method, signal transmission using electromagnetic waves is performed at a sufficiently short distance (the distance between the transmitting antenna unit 2 and the receiving antenna 3) with respect to the wavelength of the electromagnetic waves. For this reason, signal transmission by an electric field is dominant over signal transmission by electromagnetic waves. Therefore, in FIG. 9, the interaction acting between the antenna line X <b> 1, the finger 10, the finger 11, and the receiving antenna 3 is represented by a capacitance. Since no AC signal is supplied from the signal generator 1 to the antenna line X2, the capacitance between the antenna line X1 and the antenna line X2 is not affected.
Here, when the input impedance of the detection unit 4 is Z in and the frequency of the electromagnetic wave is f, the ratio of the amplitude V tx of the transmission signal at the antenna line X1 and the amplitude V rx of the reception signal at the reception antenna 3 is as follows: (2) Here, since the finger 10 is near the antenna line X1 and the finger 11 is near the receiving antenna 3, C24 << C22 and C24 << C23. For this reason, the capacitor C24 can be ignored.
As shown in Expression (2), the ratio (V rx / V tx ) between the amplitude of the transmission signal and the amplitude of the reception signal does not depend on the capacitance C21. Also, by setting the input impedance Z in to a value close to 1 / (2πfC22) and 1 / (2πfC23), the ratio (V rx / V tx ) between the amplitude of the received signal and the amplitude of the transmitted signal is set to a large value. can do.
As shown in Expression (2), the detection unit 4 detects the amplitude of the AC signal, not the capacitance, and therefore, for example, a signal having a specific frequency can be extracted by using a filter circuit (filter 42 in FIG. 3). it can. For this reason, it is possible to improve noise tolerance. In addition, since there is no dependency on the capacitor C21, even if the distance between the antenna line X1 and the antenna line X2 is narrowed, the position detection resolution can be increased without reducing the detection sensitivity.
For example, in a state where the finger 10 is stationary at a position away from the transmission antenna unit 2, the detection unit 4 detects the intensity of the reception signal for each of the antenna lines X1 to X5. Thereby, a distribution indicating the position dependency of the received signal intensity in the X direction is obtained. Moreover, the detection part 4 detects the intensity | strength of a received signal about each of antenna wire Y1-Y5. As a result, a distribution indicating the position dependency of the received signal intensity in the Y direction is obtained. From the above, it can be understood that the distribution of the intensity of the received signal on the XY plane can be obtained. FIG. 10 is a diagram illustrating the strength of the reception signal applied to the antenna lines X1 to X5. FIG. 11 is a diagram illustrating the strength of the reception signal applied to the antenna lines Y1 to Y5. In this example, the intensity of the received signal when the signal is transmitted from the antenna line X3 is the highest in the X direction, and the intensity of the received signal when the signal is transmitted from the antenna line Y2 is the highest in the Y direction. Thereby, in this example, it can be detected that the finger 10 is present near the position where the antenna line X3 and the antenna line Y2 intersect.
Thus, it can be understood that the position of the finger (conductor) with respect to the transmission antenna unit 2 can be detected by specifying the antenna line that maximizes the received signal in each of the X direction and the Y direction.
Next, distance dependency of position detection in the coordinate input device 100 will be described. As described above, in the coordinate input device 100, transmission of signals by electromagnetic waves is performed by near-field electromagnetic waves instead of the far-field used in normal radio. Communication in the near field has a greater signal distance dependency than communication in the far field, so distance determination can be easily performed.
FIG. 12 is a graph showing the distance dependency of position detection in the coordinate input device 100. In FIG. 12, the horizontal axis represents the frequency of the AC signal, and the vertical axis represents the intensity (voltage) of the received signal detected by the detection unit 4. In FIG. 12, the received signal strength when the finger is in contact with the touch panel 103 is indicated by L1 (solid line), and the received signal strength when the finger is about 5 mm away from the touch panel 103 is indicated by L2 (broken line).
As shown in FIG. 12, the intensity of the received signal becomes weaker as the finger moves away from the touch panel 103. Therefore, the detection unit 4 can detect how far the detected finger is away from the touch panel 103 by measuring the intensity of the peak of the received signal.
In the above description, the case where only one position is detected has been described, but this is merely an example. For example, it is needless to say that the positions of a plurality of fingers can be detected by detecting a plurality of peaks such as the second largest peak and the third largest peak of the received signal.
In this configuration, electromagnetic waves are transmitted between the first transmission / reception unit and the second transmission / reception unit. And the intensity | strength change of the received signal by the conductor inserted between the 1st transmission / reception part and the 2nd transmission / reception part is made into the position of the some antenna provided in the 1st transmission / reception part or the 2nd transmission / reception part. By linking, the peak position of the signal intensity is detected. Thereby, the two-dimensional position of the conductor in the surface in which the 1st transmission / reception part or the 2nd transmission / reception part was provided can be pinpointed. Furthermore, by evaluating the signal strength, it is possible to detect the distance of the conductor to the surface on which the first transmission / reception unit or the second transmission / reception unit is provided. Therefore, according to this structure, it is also possible to specify the three-dimensional position of the conductor inserted between the first transmission / reception unit and the second transmission / reception unit.
As a result, in this configuration, the position of the conductor can be detected regardless of whether the conductor is in contact with the first transmission / reception unit and the second transmission / reception unit. As a result, it is possible to solve the problem that the position of the finger cannot be detected when the finger is not in contact with the touch panel as in the capacitive touch panel.
In the above description, the signal is transmitted from the first transmission / reception unit, and the second transmission / reception unit receives the signal. However, it is also possible to adopt a configuration in which a signal is transmitted from the second transmission / reception unit, and the first transmission / reception unit receives the signal. In this case, the signal generation unit 1 may be connected to the second transmission / reception unit, and the detection unit 4 may be connected to the first transmission / reception unit.
Next, a coordinate input device according to the second embodiment will be described. In the present embodiment, a modified example of the position detection method in the position detection unit 45 of the detection unit 4 of the coordinate input device 100 will be described.
In the first embodiment, the method has been described in which the position detection unit 45 detects the position of the finger by specifying the antenna line having the maximum received signal strength in the X direction and the Y direction. However, with this method, the resolution of position detection is limited by the arrangement pitch of the antenna lines. In the present embodiment, a method for increasing the resolution of position detection without reducing the arrangement pitch of antenna lines will be described.
FIG. 13 is a diagram illustrating the strength of the reception signal applied to the antenna lines X1 to X5 in the second embodiment. As illustrated in FIG. 13, the position detection unit 45 generates a polynomial F1 that most closely approximates the received signal strength data of the antenna lines X1 to X5. Then, the position detection unit 45 detects the X coordinate XP of the peak of the polynomial F1. Similarly, the same polynomial approximation is performed for the intensity of the received signals corresponding to the antenna lines Y1 to Y5, and the Y coordinate YP of the peak of the polynomial is detected. Thereby, the position detection part 45 can detect a coordinate (XP, YP) as a finger | toe position.
In the present embodiment, by interpolating between the antenna lines with a polynomial, the position detection resolution can be made smaller than the arrangement pitch of the antenna lines. Thereby, it is possible to realize a coordinate input device having a better position detection resolution than that of the first embodiment.
Next, a coordinate input apparatus according to the third embodiment will be described. In the present embodiment, a modified example of the position detection method in the position detection unit 45 of the detection unit 4 of the coordinate input device 100 will be described.
FIG. 14 is a diagram illustrating the strength of the reception signal applied to the antenna lines X1 to X5 in the third embodiment. The position detection unit 45 stores an expected distribution of the received signal in advance, and detects the position of the finger by collating this distribution with data. As illustrated in FIG. 14, the position detection unit 45 applies the expected distribution D to the received signal strength data of the antenna lines X1 to X5. At this time, the fitting is performed so that the correlation between the received signal strength data of the antenna lines X1 to X5 and the expected distribution D is maximized. Then, the position detection unit 45 detects the X coordinate XP of the peak of the expected distribution D. Similarly, the predicted distribution is similarly applied to the intensities of the received signals corresponding to the antenna lines Y1 to Y5, and the Y coordinate YP of the peak of the predicted distribution is detected. At this time, the fitting is performed so that the correlation between the received signal strength data of the antenna lines Y1 to Y5 and the expected distribution is maximized. Thereby, the position detection part 45 can detect a coordinate (XP, YP) as a finger | toe position.
In the present embodiment, by applying an expected distribution to the received signal intensity corresponding to each antenna line, the position detection resolution can be made smaller than the arrangement pitch of the antenna lines. Thereby, it is possible to realize a coordinate input device having a better position detection resolution than that of the first embodiment.
Next, a coordinate input device according to the fourth embodiment will be described. In the present embodiment, the influence of the antenna line of the transmitting antenna unit 2 and the shape of the receiving antenna 3 will be described. FIG. 15 is a diagram schematically showing an electric field in the cross section of the antenna line X1 of the linear transmission antenna unit 2. As shown in FIG. The antenna line X1 is merely a representative example, and the antenna lines X2 to X5 and Y1 to Y5 also form a similar electric field. FIG. 16 is a diagram schematically showing an electric field in a cross section of the planar receiving antenna 3. In FIG. 15 and FIG. 16, an equipotential line EL is displayed. Since the receiving antenna 3 is planar, when the finger 10 is in the vicinity of the receiving antenna 3, the intensity of the transmitted signal changes by 1 / th power of the distance. On the other hand, since the antenna line X1 is linear, when the finger 10 is in the vicinity of the receiving antenna, the intensity of the transmitted signal changes by 1 / square of the distance. That is, the linear antenna line X1 has a large distance dependency of the signal intensity, and the planar receiving antenna 3 has a small distance dependency.
That is, the dependence of the distance between the receiving antenna 3 and the human body on the signal intensity can be reduced by making the antenna line of the transmitting antenna unit 2 linear and the receiving antenna 3 planar. Thereby, the distance between the antenna line of the transmission antenna unit 2 and the finger 10 can be detected with high accuracy.
Next, a coordinate input device 500 according to the fifth embodiment will be described. A coordinate input device 500 is a modification of the coordinate input device 100 according to the first embodiment. FIG. 17 is a diagram schematically illustrating a configuration of a coordinate input device 500 according to the fifth embodiment. The coordinate input device 500 has a configuration in which the signal generation unit 1 of the coordinate input device 100 is replaced with a signal generation unit 5. Other configurations of the coordinate input device 500 are the same as those of the coordinate input device 100.
FIG. 18 is a diagram schematically illustrating the configuration of the signal generation unit 5 and the transmission antenna unit 2. The signal generation unit 5 has a configuration in which the signal oscillation unit 11 of the signal generation unit 1 is replaced with a signal oscillation unit 51. The signal oscillating unit 51 outputs AC signals having different frequencies in accordance with the control signal CON1 from the detecting unit 4. In this example, the signal oscillating unit 51 outputs an AC signal SIG1 having a frequency f1 or an AC signal SIG2 having a frequency f2. In order to simplify the drawing, the display of the internal structure of the MUX 13 is omitted in FIG. For example, the frequency f1 can be set to 1 MHz to 10 MHz, and the frequency f2 can be set to 10 kHz to 1 MHz. The frequency of the signal output from the signal oscillating unit is not limited to two but may be three or more.
In general, the higher the frequency of electromagnetic waves, the stronger the directivity of the antenna. FIG. 19 is a diagram schematically illustrating the spread of electromagnetic waves when the antenna wire X1 is viewed from the cross-sectional direction. In FIG. 9, the spread of the electric field when the frequency of the electromagnetic wave is high is indicated by a solid line L11, and the spread of the electric field when the frequency of the electromagnetic wave is low is indicated by a broken line L12. The antenna line X1 is only a representative example, and the antenna lines X2 to X5 and Y1 to Y5 are the same as the antenna line X1. When a low-frequency signal is used, the dependency of the obtained signal strength on the finger position is reduced, and the difference in signal strength between antennas is reduced. On the other hand, when a high-frequency signal is used, the dependence of the obtained signal strength on the finger position increases, and the difference in signal strength between antennas increases.
The following position detection can be realized by utilizing the influence of the difference in frequency of electromagnetic waves. First, the intensity of the low frequency signal is measured, and the distance between the finger and the transmitting antenna unit 2 is estimated. Since the directivity of the antenna when using a low-frequency signal is weak, the position dependency in the direction parallel to the main surface of the transmitting antenna unit 2 is reduced. As a result, the distance measurement accuracy with respect to the direction perpendicular to the main surface of the transmitting antenna unit 2 is improved.
Next, when a high-frequency signal is used, the directivity of the antenna is strong, so that the difference in signal strength between the antennas increases. Therefore, the position dependency in the direction parallel to the main surface of the transmitting antenna unit 2 is increased. As a result, the detection accuracy of the finger position in the direction parallel to the main surface of the transmitting antenna unit 2 is increased.
As described above, by changing the frequency of the AC signal with time, the measurement accuracy of the distance with respect to the direction perpendicular to the main surface of the transmission antenna unit 2 and the finger in the direction parallel to the main surface of the transmission antenna unit 2 are obtained. Both the position detection accuracy can be improved.
Next, a coordinate input device 600 according to the sixth embodiment will be described. A coordinate input device 600 is a modification of the coordinate input device 100 according to the first embodiment. FIG. 20 is a diagram schematically illustrating a configuration of a coordinate input device 600 according to the sixth embodiment. The coordinate input device 600 has a plurality of receiving antennas. FIG. 20 illustrates an example in which the coordinate input device 600 includes receiving antennas 61 to 63. The reception antennas 61 to 63 are alternatively connected to the detection unit 4 by a multiplexer (MUX) 60. The detection unit 4 can control which of the reception antennas 61 to 63 is connected to the detection unit 4 by the control signal CON2.
Next, an arrangement mode of the receiving antennas 61 to 63 will be described. FIG. 21 is a perspective view illustrating an example of a mobile terminal 601 on which a touch panel on which the coordinate input device 600 is mounted is mounted, as viewed from the touch panel side (front side). A portable terminal 601 is provided with a touch panel 603 on a surface 604 of a housing 602. The transmission antenna unit 2 is incorporated in the touch panel 603. In this example, the receiving antenna 61 is disposed on the outer periphery of the touch panel 603 on the surface 604. The receiving antenna 62 is disposed on the side surface 605 of the mobile terminal 601.
FIG. 22 is a perspective view showing an example when the portable terminal 601 on which the touch panel on which the coordinate input device 600 is mounted is mounted is viewed from the side (back side) opposite to the touch panel side (front side). The receiving antenna 63 is disposed on the back surface 606 of the mobile terminal 601.
The receiving antenna 63 disposed on the back surface 606 can receive electromagnetic waves efficiently when the portable terminal 601 is held in the hand. However, when the portable terminal 601 is placed on a desk with the back side down, the back side 606 is hidden, so that the receiving antenna 63 is difficult to receive electromagnetic waves. However, since the receiving antenna 61 on the front surface 604 and the receiving antenna 62 on the side surface 605 are exposed, it is easy to receive electromagnetic waves. As described above, the reception antenna with the optimum reception sensitivity varies depending on how the portable terminal incorporating the coordinate input device is used. Therefore, by arranging a plurality of receiving antennas on different surfaces like the portable terminal 601, it is possible to cope with a change in receiving sensitivity depending on how to use the terminal incorporating the coordinate input device.
In addition, switching of the receiving antennas 61 to 63 can be performed in order. FIG. 23 is a diagram illustrating the switching timing of the receiving antennas 61 to 63. Since there are ten antenna lines of the transmission antenna unit 2, the reception antenna to be used can be switched every time the reception intensity corresponding to the ten antenna lines is measured. Then, among the reception antennas 61 to 63, the one having the optimum reception intensity, for example, the reception antenna having the strongest average reception intensity corresponding to each antenna line is determined. Then, the finger position may be detected using the signal strength received by the determined receiving antenna.
The above-described reception antenna switching may be performed continuously, or after the optimal reception antenna is determined, the reception antenna switching may be stopped and the determined reception antenna may be used continuously.
In the present embodiment, the case where there are three reception antennas has been described, but the number of reception antennas may be two or four or more.
Next, a coordinate input device 700 according to the seventh embodiment will be described. A coordinate input device 700 is a modification of the coordinate input device 600 according to the sixth embodiment. FIG. 24 is a diagram schematically illustrating a configuration of the coordinate input device 700 according to the seventh embodiment. Similar to the coordinate input device 600, the coordinate input device 700 includes a plurality of receiving antennas. FIG. 24 illustrates an example in which the coordinate input device 700 includes reception antennas 71 to 75. The reception antennas 71 to 75 are alternatively connected to the detection unit 4 by a multiplexer (MUX) 70. The detection unit 4 can control which of the reception antennas 71 to 75 is connected to the detection unit 4 by the control signal CON3.
Next, an arrangement mode of the receiving antennas 71 to 75 will be described. FIG. 25 is a perspective view illustrating an example of a portable terminal 701 on which a touch panel mounted with the coordinate input device 700 is mounted as viewed from the touch panel side (front side). A portable terminal 701 is provided with a touch panel 703 on a surface 704 of a housing 702. The transmission antenna unit 2 is incorporated in the touch panel 703. In this example, the receiving antennas 71 to 74 are arranged on the outer periphery of the touch panel 603 on the surface 604. Note that the receiving antenna 75 is disposed at the same position as the receiving antenna 63, and thus detailed description thereof is omitted.
As illustrated in FIG. 25, a touch panel 703 is disposed at the center of the surface 704 of the mobile terminal 701. The receiving antennas 71 to 74 are arranged in the periphery of the touch panel 703 on the surface 704. The receiving antennas 71 and 72 are band-shaped antennas whose longitudinal direction is the X direction. FIG. 26 is a diagram illustrating a correspondence relationship between the receiving antennas 71 and 72 and the antenna line. The reception antennas 71 and 72 are used for reception when electromagnetic waves are radiated from the antenna lines X1 to X5 of the transmission antenna unit 2.
The receiving antennas 71 and 72 are arranged to face each other with the transmitting antenna unit 2 interposed therebetween. The receiving antennas 73 and 74 are band-shaped antennas whose longitudinal direction is the Y direction. The receiving antennas 73 and 74 are arranged to face each other with the transmitting antenna unit 2 interposed therebetween. FIG. 27 is a diagram illustrating a correspondence relationship between the receiving antennas 73 and 74 and the antenna line. The reception antennas 73 and 74 are used for reception when electromagnetic waves are radiated from the antenna lines Y1 to Y5 of the transmission antenna unit 2.
In the portable terminal 701, the distance between the receiving antenna and each antenna line is equal. Specifically, the distance between the receiving antenna 71 and the antenna lines X1 to X5 is unified to Lx. Although not shown in the figure, the distance between the receiving antenna 72 and the antenna lines X1 to X5 is unified to Lxb. Here, Lx and Lxb may be the same or different. The distance between the receiving antennas 73 and 74 and the antenna lines Y1 to Y5 is unified to Ly. Although not shown in the figure, the distance between the receiving antenna 74 and the antenna lines Y1 to Y5 is unified to Lyb. Here, Ly and Lyb may be the same or different. Thereby, when the finger is not approaching the panel, the signal intensity transmitted from each transmitting antenna to the receiving antenna becomes uniform, so that the finger position detection accuracy can be improved.
In the above description, the example having the reception antennas 71 and 72 has been described. However, this is only an example, and only one of the reception antennas 71 and 72 may be arranged. Moreover, although the example which has the receiving antennas 73 and 74 was demonstrated, this is only an illustration and you may arrange | position only any one of the receiving antennas 73 and 74.
Furthermore, the position where the receiving antenna is disposed is not limited to the surface where the touch panel is disposed. Below, the modification of the coordinate input device 700 is demonstrated. FIG. 28 is a perspective view illustrating an example of a mobile terminal 707 mounted with a touch panel on which a coordinate input device, which is a modification of the coordinate input device 700, is viewed from the touch panel side (front side). In FIG. 28, the receiving antenna 76 having the X direction as the longitudinal direction is disposed on the side surface 708 of the portable terminal 707, and the receiving antenna 77 having the Y direction as the longitudinal direction is disposed on the side surface 705.
A side surface 708 of the portable terminal 707 is a surface perpendicular to the Y direction. The receiving antenna 76 having the longitudinal direction in the X direction is disposed on the side surface 708. Therefore, the distance between the receiving antenna 76 and the antenna lines X1 to X5 is unified to Lx.
A side surface 705 of the portable terminal 707 is a surface perpendicular to the X direction. The reception antenna 77 having the Y direction as the longitudinal direction is disposed on the side surface 705. Therefore, the distance between the receiving antenna 77 and the antenna lines Y1 to Y5 is unified to Ly.
Therefore, in the portable terminal 707, as in the portable terminal 701, the distance between the reception antenna and each antenna line is equal. Thereby, when the finger is not approaching the panel, the signal intensity transmitted from each transmitting antenna to the receiving antenna becomes uniform, so that the finger position detection accuracy can be improved.
In addition, although this embodiment demonstrated the case where the number of receiving antennas was five, 2-4 or 6 or more receiving antennas may be sufficient.
Next, a coordinate input device according to an eighth embodiment will be described. In the present embodiment, a method for preventing erroneous detection in the position detection unit 45 of the detection unit 4 of the coordinate input device 100 will be described.
FIG. 29 is a diagram illustrating the strength of the reception signal of the antenna lines X1 to X5 according to the eighth embodiment. In this example, the signal intensity when the antenna line X3 is used is maximum. FIG. 30 is a diagram illustrating the strength of the reception signal applied to the antenna lines Y1 to Y5 according to the eighth embodiment. In this example, the signal strengths of the antenna lines Y1 to Y5 are low values that are substantially equal.
If the finger approaches the transmitting antenna unit 2, a signal intensity peak occurs in any of the X directions (antenna lines X1 to X5). In addition, a signal intensity peak occurs in any of the Y directions (antenna lines Y1 to Y5). The coordinate input device 100 can detect the position of the finger as XY coordinates by using the peak in the X direction and the peak in the Y direction.
However, in this embodiment, a signal intensity peak occurs in the X direction, but no signal intensity peak occurs in the Y direction. That is, in this case, it can be seen that the peak of the signal intensity in the X direction is not caused by the finger approaching the transmitting antenna unit 2. That is, when a peak occurs in one of the signal intensity in the X direction and the signal intensity in the Y direction, it is determined that the peak was erroneously detected due to a factor other than the approach of the finger, and the position detection is not performed. be able to.
For example, the threshold value Xth is set for the signal strength in the X direction, and the threshold value Yth is set for the signal strength in the Y direction. Then, the finger position may be detected when the signal intensity in the X direction is equal to or greater than the threshold value Xth and the signal intensity in the Y direction is equal to or greater than the threshold value Yth.
As described above, erroneous position detection can be prevented by performing position detection when peaks occur in both the signal intensity in the X direction and the signal intensity in the Y direction.
Next, a coordinate input device 900 according to the ninth embodiment will be described. FIG. 31 is a diagram schematically illustrating the configuration of the coordinate input device 900 according to the ninth embodiment. The coordinate input device 900 has a configuration in which a multiplexer (MUX) 90 is added to the coordinate input device 100 according to the first embodiment. The MUX 90 is configured to connect the detection unit 4 to any one of the ten antenna lines of the transmission antenna unit 2 and the reception antenna 3. Note that the detection unit 4 can control which of the ten antenna lines of the transmission antenna unit 2 or the reception antenna 3 is connected to the detection unit 4 by the control signal CON4.
When the distance between the finger and the transmitting antenna unit 2 is large, the coordinate input device 900 receives an electromagnetic wave using the receiving antenna 3 and detects the position of the finger as shown in FIG. In this case, the MUX 90 connects the reception antenna 3 and the detection unit 4.
On the other hand, when the distance between the finger and the transmission antenna unit 2 is small, the coordinate input device 900 can detect the position of the finger using only the antenna line of the transmission antenna unit 2. Hereinafter, a mechanism of finger position detection using only the antenna line of the transmission antenna unit 2 will be described.
FIG. 32 is a diagram illustrating position detection of the coordinate input device 900 when the distance between the finger 10 and the transmission antenna unit 2 is small. In FIG. 32, only the antenna lines X1 and X2 are illustrated among the antenna lines of the transmission antenna unit 2 for simplification. When the distance between the finger and the transmitting antenna unit 2 is small, the signal generating unit 1 supplies an AC signal to the antenna line X1. The MUX 90 connects the antenna line X <b> 2 and the detection unit 4. In this case, a capacitance C31 is generated between the antenna line X1 and the antenna line X2. A capacitance C32 is generated between the antenna line X1 and the finger. A capacitance C33 is generated between the finger and the antenna line X2.
When the input impedance of the detection unit 4 is Z in and the frequency of the electromagnetic wave is f, the ratio between the amplitude V tx of the transmission signal at the antenna line X1 and the amplitude V rx of the reception signal at the antenna line X2 (receiving antenna) is It is represented by the following formula (3).
Here, when the finger is far from the touch part, C32 << C31 and C33 << C31 are satisfied, so Expression (3) can be approximated by Expression (4) below.
In this case, the amplitude of the received signal does not depend on the capacitors C32 and C33. That is, the amplitude of the received signal does not depend on the finger position. That is, when the finger is away from the transmission antenna unit 2, the strength of the received signal does not depend on the finger position. On the other hand, when the finger is close to the transmission antenna unit 2, that is, when the finger is in contact with the touch panel, the position is detected by the above-described equation (1). As a result, the intensity of the received signal changes only when the finger is close to the transmitting antenna unit 2 (when the finger is in contact with the touch panel). It is possible to accurately determine whether or not the transmission antenna unit 2 is close (whether or not the finger is in contact with the touch panel).
The coordinate input device 900 performs the operation described below by accurately determining whether or not the finger is close to the transmission antenna unit 2 (whether or not the finger is in contact with the touch panel). Can do. FIG. 33 is a flowchart showing the operation of the coordinate input device 900.
As shown in FIG. 32, the coordinate input device 900 uses an antenna line as a receiving antenna (short-distance connection) at the time of activation.
The detection unit 4 determines whether or not the finger is close to the transmission antenna unit 2 (whether or not the finger is in contact with the touch panel).
When the finger is close to the transmission antenna unit 2 (the finger is in contact with the touch panel), the detection unit 4 maintains the connection relationship. Then, the measured signal value is set as a reference value when the distance between the finger and the touch panel is zero. Then, it returns to step S11.
When the finger is not close to the transmission antenna unit 2 (the finger is not in contact with the touch panel), the detection unit 4 switches the connection of the MUX 90 (changes to the connection for long distance). Thereby, even when the receiving antenna 3 and the detection unit 4 are connected and the finger is not close to the transmission antenna unit 2 (the finger is not in contact with the touch panel), the detection unit 4 can detect the position of the finger. Can do. Since the reference value is set when the distance between the finger and the touch panel is 0, the distance between the finger and the touch panel can be accurately measured. Thereafter, the process returns to step S11.
Therefore, according to this configuration, since the reference value can be calibrated at the time of short-distance connection, even when the finger is away from the transmission antenna unit (touch panel), the finger is not connected between the transmission antenna unit (touch panel). The distance can be detected with high accuracy.
Next, a coordinate input apparatus 1000 according to the tenth embodiment will be described. FIG. 34 is a diagram schematically illustrating a configuration of the coordinate input device 1000 according to the tenth embodiment. The coordinate input device 1000 has a configuration in which a MUX 14 and an ammeter AMM are added to the coordinate input device 100 according to the first embodiment. The MUX 14 is configured to connect the ten antenna lines of the transmission antenna unit 2 and the ammeter AMM. The detection unit 4 can control which of the antenna lines is connected to the detection unit 4 by the control signal CON5.
FIG. 35 is a diagram illustrating the connection of the coordinate input device 1000 when the position of the finger 10 is detected by the capacitance type. In FIG. 35, only the antenna lines X1 and X2 are illustrated among the antenna lines of the transmission antenna unit 2 for simplification. In this example, the MUX 13 connects the signal oscillation unit 11 and the antenna line X1. The MUX 14 connects the antenna line X2 and the ammeter AMM. As a result, as in the case shown in FIG. 8, it is possible to detect the position by the capacitance type.
FIG. 36 is a diagram illustrating the connection of the coordinate input device 1000 when detecting the position of the finger when the finger 10 and the transmission antenna unit 2 are separated from each other. In FIG. 36, only the antenna lines X1 and X2 are illustrated among the antenna lines of the transmission antenna unit 2 for simplification. In this example, the MUX 13 connects the signal oscillation unit 11 and the antenna line X1. The MUX 14 does not connect the ammeter AMM to any antenna line. As a result, as in the case shown in FIG. 9, the finger position can be detected even when the finger is away from the transmission antenna unit 2.
By using the capacitance type and the position detection method when the finger and the transmission antenna unit 2 are separated from each other, the coordinate input device 1000 can perform the operation described below. FIG. 37 is a flowchart showing the operation of the coordinate input apparatus 1000.
When the coordinate input device 1000 is activated, as shown in FIG. 35, the coordinate input device 1000 performs a connection for detecting a position by a capacitance type. That is, the signal generator 1 and the antenna line (antenna line X1 in FIG. 35) are connected by the MUX 13, and the antenna line (antenna line X2 in FIG. 35) and the ammeter AMM are connected by the MUX 14.
The detection unit 4 determines whether or not the finger is in contact with the touch panel.
When the finger is in contact with the touch panel, the detection unit 4 detects the position of the finger as it is. Then, the measured signal value is set as a reference value when the distance between the finger and the touch panel is zero. Then, it returns to step S21.
When the finger is not in contact with the touch panel, the detection unit 4 switches the connection of the MUX 14 (changes to a long distance connection). Thereby, even when the finger is not in contact with the touch panel, the detection unit 4 can detect the position of the finger. Since the reference value is set when the distance between the finger and the touch panel is 0, the distance between the finger and the touch panel can be accurately measured. Thereafter, the process returns to step S21.
Therefore, according to this configuration, since the reference value can be calibrated using the value measured by the capacitance type, even when the finger is away from the transmission antenna unit (touch panel), the finger and the transmission antenna unit The distance to the (touch panel) can be accurately detected. In addition, the position of the finger can be detected with high accuracy by switching the measurement method in accordance with finger back-eating / non-contact.
Next, a coordinate input device 1100 according to the eleventh embodiment will be described. A coordinate input device 1100 is a modification of the coordinate input device 100 according to the first embodiment. FIG. 38 is a diagram schematically illustrating a configuration of the coordinate input device 1100 according to the eleventh embodiment. The coordinate input device 1100 has a configuration in which a carrier wave generation unit 6 is added to the coordinate input device 100, and the signal generation unit 1 and the detection unit 4 of the coordinate input device 100 are replaced with a signal generation unit 7 and a detection unit 8, respectively. Have. Other configurations of the coordinate input device 1100 are the same as those of the coordinate input device 100.
FIG. 39 is a diagram schematically showing the configuration of the signal generator 7. The signal generator 7 has a configuration in which a mixer M1 is added to the signal generator 1. The mixer M <b> 1 is inserted between the signal oscillating unit 11 and the amplifier 12. The mixer M1 mixes the AC signal SIG from the signal oscillation unit 11 and the carrier wave CW from the carrier wave generation unit 6 and outputs the mixed signal to the amplifier 12. The other configuration of the signal generation unit 7 is the same as that of the signal generation unit 1, and thus the description thereof is omitted.
FIG. 40 is a diagram schematically illustrating the configuration of the detection unit 8. The detection unit 8 has a configuration in which a mixer M2 is added to the detection unit 4. The mixer M2 is inserted between the amplifier 41 and the filter 42. The mixer M2 mixes the received signal with the carrier wave CW and converts it into a received signal having a frequency component of the AC signal SIG of the signal oscillating unit 11. Since the other structure of the detection part 8 is the same as that of the detection part 4, description is abbreviate | omitted.
According to this configuration, it is possible to improve frequency selectivity without using a filter having a steep characteristic as compared with the case of directly transmitting an AC signal. As a result, it is advantageous in that noise resistance can be increased.
Furthermore, the carrier wave generation unit 6 can periodically change the frequency of the output carrier wave CW within a certain range. Further, the frequency of the AC signal output from the signal generator 7 may be periodically changed within a certain range. This frequency change can be performed once per frequency within a period in which one antenna line is selected, or can be changed once every 10 antenna lines are selected.
FIG. 41 is a diagram illustrating a frequency spectrum of noise when the frequencies of the carrier wave and the AC signal are changed. When the frequency is changed in this way, the frequency spectrum of noise radiated from the transmitting antenna unit 2 can be expanded in a certain frequency range (solid line N1 in FIG. 41). Therefore, it is possible to prevent noise concentration on the specific frequency (broken line N2 in FIG. 41). As a result, it is possible to reduce the influence of radiation noise on other devices.
Next, a coordinate input device according to Embodiment 12 will be described. The coordinate input device according to the twelfth embodiment has the same configuration as the coordinate input device 100 according to the first embodiment. In this embodiment, an application example in the case where an antenna line for transmitting an AC signal is fixed to one will be described.
In the above-described embodiment, the antenna line for transmitting the AC signal is switched in time series. In contrast, in the present embodiment, an AC signal is continuously transmitted from one antenna line. FIG. 42 is a diagram schematically illustrating position detection by the coordinate input device according to the twelfth embodiment. 42 shows only the antenna lines X1 and X2 among the antenna lines of the transmission antenna unit 2 for simplification. In FIG. 42, the antenna line to be continuously used is the antenna line X1. .
In the present embodiment, for example, an AC signal is continuously transmitted from the antenna line X1, and a temporal change in the strength of the received signal is observed. At this time, if the human body 10c is present in the signal transmission path (between the transmitting antenna unit 2 and the receiving antenna 3), the human body 10c may be affected by a pulse or the like even if the transmitted signal is a regular sine wave. As a result, the signal transmission characteristics change over time. Therefore, the received signal has a waveform in which the above-described temporal change is superimposed and the amplitude changes temporally. Therefore, the pulse of the human body 10c can be detected by extracting a low frequency component of about several Hz from the received signal by filtering.
FIG. 43 is a diagram illustrating an example of a waveform of a low-frequency component extracted from the received signal. According to the present embodiment, it is possible to acquire the waveform component indicating the pulse of the human body in this way. As a result, for example, the pulse data can be used for health management of a user who uses the mobile terminal. Furthermore, by detecting the presence or absence of a pulse, it is possible to determine whether or not the conductor approaching the coordinate input device according to the present embodiment is a living thing.
Other Embodiments The present invention is not limited to the above-described embodiments, and can be appropriately changed without departing from the spirit of the present invention. For example, in the above-described embodiment, the example in which the transmission antenna unit is incorporated in the touch panel and the reception antenna is arranged in the other part has been described, but this is only an example. For example, a coordinate input device similar to the coordinate input device according to the above-described embodiment is provided even if one or a plurality of reception antennas are incorporated in the touch panel and a configuration equivalent to the antenna line of the transmission antenna unit is disposed in other portions. Can be realized.
Needless to say, the coordinate input device 500 can be provided with a plurality of receiving antennas. For example, the coordinate input device 500 may be provided with a plurality of antennas and multiplexers as in the coordinate input device 600 or 700. In addition, setting of a set value (coordinate input device 900 of the ninth embodiment), detection method switching (coordinate input device 1000 of the tenth embodiment), and use of a carrier wave (coordinates of the eleventh embodiment) are set in the coordinate input device 500. It is also possible to combine some or all of the input devices 1100).
Needless to say, the coordinate input devices 900, 1000, and 1100 can be provided with a plurality of receiving antennas. For example, the coordinate input devices 900, 1000, and 1100 may be provided with a plurality of antennas and multiplexers as in the coordinate input device 600 or 700. Setting value setting (coordinate input device 900 according to the ninth embodiment), detection method switching (coordinate input device 1000 according to the tenth embodiment), and use of carrier waves (coordinate input device 1100 according to the eleventh embodiment) are appropriately combined. Can be used.
Needless to say, the technology described in each of the embodiments described above can be applied to the coordinate input devices 500, 600, 700, 900, 1000, 1100, and other coordinate input devices having the combinations described above. That is, the coordinate input devices 500, 600, 700, 900, 1000, 1100, and other coordinate input devices based on the combinations described above are improved in detection accuracy by using a polynomial (second embodiment) or by using an expected distribution. Improvement in detection accuracy (Embodiment 3) can be applied. In addition, the coordinate input devices 500, 600, 700, 900, 1000, 1100, and other coordinate input devices having the above-described combinations are improved in detection accuracy and error due to the shape of the antenna line and the receiving antenna (Embodiment 4). A part 1 or all of the techniques of prevention of detection (Embodiment 8) and pulse measurement of a human body (Embodiment 12) can be applied.
In the above-described embodiment, in order to describe the configuration of the coordinate input device and the mobile terminal, the X direction and the Y direction are assumed to be orthogonal to each other. However, the X direction and the Y direction do not necessarily have to be orthogonal to each other, and may intersect at a predetermined angle other than a right angle.
(Supplementary note 1) The signal between the signal generation unit that outputs an AC signal, the first transmission / reception unit having a plurality of first antennas that transmit and receive a signal corresponding to the AC signal, and the first transmission / reception unit A second transmitter / receiver having one or more second antennas for transmitting / receiving the signal, and the signal corresponding to the position of the plurality of first antennas when the first transmitter / receiver transmits / receives the signal. A coordinate input device comprising: a detection unit that acquires an intensity distribution and detects a detection position according to a peak position of the intensity distribution.
(Additional remark 2) The said signal generation part outputs the said alternating current signal to either of the said some 1st antennas of the said 1st transmission / reception part, and the said alternating current signal is supplied among several 1st antennas. The coordinate input device according to appendix 1, wherein the signal is transmitted from a first antenna, and the second transmission / reception unit receives the signal by a second antenna.
(Additional remark 3) The said signal generation part outputs the said alternating current signal to a said 2nd transmission / reception part, and the said signal is transmitted with a 2nd antenna from the said 2nd transmission / reception part, Among several 1st antennas The coordinate input device according to claim 1, wherein the signal is received by any one of the above.
(Appendix 4) The detection unit receives the signal via a conductor, and the detection position indicates a position of the conductor.
The coordinate input device according to attachment 1.
(Supplementary note 5) The coordinate input device according to supplementary note 4, wherein the conductor is a human body.
(Supplementary note 6) The coordinate input device according to supplementary note 1, wherein the detection unit detects one or a plurality of the detection positions according to one or a plurality of the peaks.
(Supplementary note 7) The plurality of first antennas are arranged in a predetermined direction, and the detection unit determines the intensity of the signal detected for the plurality of first antennas in the position in the predetermined direction. The coordinate input device according to appendix 1, wherein the coordinate input device is approximated by a polynomial as a variable and detects the position in the predetermined direction where the value of the polynomial is maximum as the detection position.
(Supplementary note 8) The plurality of first antennas are arranged in a predetermined direction, and the detection unit sets the position of the predetermined direction to the intensity of the signal detected for the plurality of first antennas. The coordinate input device according to appendix 1, wherein a predicted distribution as a variable is applied, and a position in the predetermined direction where the correlation with the predicted distribution is maximized is detected as the detection position.
(Additional remark 9) The said detection part is inserted between the 1st antenna of the said 1st transmission / reception part and the 2nd antenna of the said 2nd transmission / reception part based on the intensity | strength of the said signal in the said detection position. The coordinate input device according to appendix 2, wherein a distance between the first conductor and the first antenna of the first transmission / reception unit is detected.
(Additional remark 10) The said signal generation part outputs several types of alternating current signal from which frequency differs, The said detection part is said 1st when the said signal generation part is outputting the alternating current signal of 1st frequency. A plane including the first antenna when a position parallel to the plane including the antenna is detected and the signal generator outputs an AC signal having a second frequency higher than the first frequency. The coordinate input device according to appendix 9, wherein a position perpendicular to is detected.
(Supplementary Note 11) The detection unit includes:
The signal from one antenna line among the plurality of first antennas is received by the second transmitting / receiving unit via another antenna of the plurality of first antennas,
When the intensity of the received signal is greater than a predetermined value, set as a reference intensity when the distance between the conductor and the first transmission / reception unit is 0,
The coordinate input device according to appendix 10.
(Supplementary Note 12) The first transmission / reception unit is incorporated in a capacitive touch panel, and all or a plurality of the plurality of first antennas function as electrodes of the capacitive touch panel. The coordinate input device according to 9.
(Supplementary note 13) In parallel or independently of position detection of the capacitive touch panel, the signal generation unit outputs the AC signal to any of the plurality of first antennas of the first transmission / reception unit, The coordinate input device according to attachment 12, wherein the detection unit detects the detection position by comparing the intensity of the signal detected for each of the plurality of first antennas.
(Supplementary Note 14) A carrier generation unit that outputs a carrier wave to the signal generation unit and the detection unit is further included. The signal generation unit mixes and outputs the AC signal and the carrier, and the first transmission / reception unit The plurality of first antennas transmit the mixed AC signal and the signal corresponding to the carrier wave, and the detection unit removes the carrier wave for each of the plurality of first antennas. The coordinate input device according to appendix 1, wherein the intensity of the signal corresponding to an AC signal is detected.
(Supplementary note 15) The coordinate input device according to supplementary note 14, wherein the carrier wave generation unit outputs a carrier wave whose frequency changes with time.
(Supplementary Note 16) A plurality of the second transmission / reception units are provided, and the detection unit receives each of the plurality of first antennas from a second antenna of the plurality of second transmission / reception units. The coordinate input device according to appendix 1, wherein a signal position is detected and a detection position is detected according to the position of the first antenna where the detected signal intensity is maximum.
(Additional remark 17) The said 2nd transmission / reception part is provided with two or more, The said detection part received with the 2nd antenna in any one of a said some 2nd transmission / reception part about each of the said some 1st antenna After detecting the signal strength and comparing the detected signal strengths to detect the detection position, each of the plurality of first antennas is subjected to another second of the plurality of second transmission / reception units. The coordinate input device according to appendix 1, wherein the intensity of the signal received by any one of the second antennas of the transmitting / receiving unit is detected, and the detected position is detected by comparing the detected intensity of the signal.
(Supplementary note 18) The plurality of first antennas includes a plurality of first antenna sets aligned in a first direction and a plurality of second antenna sets aligned in a second direction different from the first direction. And the detection unit detects the intensity of the signal received by the second transmission / reception unit for each antenna of the plurality of first antenna sets, and compares the detected signal strength. Detecting the first position, detecting the intensity of the signal received by the second transmitting / receiving unit for each of the plurality of second antenna sets, and comparing the detected intensity of the signal to the second position The coordinate input device according to appendix 1, wherein the coordinate input device detects the coordinates represented by the first position and the second position as the detection position.
(Supplementary Note 19) When the detection unit does not match a first position detected using the plurality of first antenna sets and a second position detected using the plurality of second antenna sets. The coordinate input device according to appendix 18, wherein the first and second detection positions are invalidated.
(Additional remark 20) It has two or more said 2nd transmission / reception parts, The said detection part detects the intensity | strength of the said signal received in either of several said 2nd transmission / reception parts about each of these 1st antennas The coordinate input device according to appendix 18, wherein the detected position is detected by comparing the detected intensities of the signals.
(Additional remark 21) The said detection part extracts a predetermined | prescribed frequency component from the intensity | strength of the said signal received by the said 2nd transmission / reception part about either of these 1st antennas, and the 1st transmission / reception part of the said 1st transmission / reception part The coordinate input device according to appendix 1, wherein a change in state of a conductor inserted between the first antenna and the second antenna of the second transmission / reception unit is detected.
(Supplementary note 22) The coordinate input device according to supplementary note 20, wherein the conductor is a human body, and the detection unit detects a pulse from an intensity change of the predetermined low-frequency component.
(Supplementary note 23) The coordinate input device according to supplementary note 22, wherein in the supplementary note 22, whether or not the conductor is a living organism is determined based on presence or absence of a pulse.
(Supplementary note 24) The coordinate input device according to supplementary note 1, wherein the wavelength of the AC signal is 10 times or more the size of the first transmission / reception unit and the second transmission / reception unit.
(Supplementary Note 25) Each of the plurality of antennas is a linear antenna disposed along a main surface of the first transmission / reception unit, and the second transmission / reception unit is a flat antenna. The coordinate input device according to 1.
(Supplementary Note 26) A coordinate input device for detecting the position of a conductor, a first transmission / reception having a signal generating unit for outputting an AC signal and a plurality of first antennas for transmitting / receiving a signal corresponding to the AC signal. And a second transmitter / receiver having one or more second antennas for transmitting / receiving the signal between the first transmitter / receiver and the first transmitter / receiver when the first transmitter / receiver transmits / receives the signal. The signal intensity distribution corresponding to the positions of the plurality of first antennas is acquired, and the plurality of first antennas and the second transmission / reception of the first transmission / reception unit according to the position of the peak of the intensity distribution A detection unit that detects a position of the conductor inserted between one or a plurality of second antennas of the unit.
(Supplementary note 27) The coordinate input device according to Supplementary note 26 is incorporated, and the plurality of first antennas of the first transmission / reception unit are arranged only on the first surface, and the plurality of second transmission / reception units Each of the second antennas is a mobile terminal arranged on the first surface or a surface different from the first surface.
(Supplementary Note 28) The plurality of second transmission / reception units include a third transmission / reception unit and a fourth transmission / reception unit, and the third transmission / reception unit is equidistant from each of the plurality of first antennas. The first transmitting / receiving unit is spaced apart from the first transmitting / receiving unit in the first direction, and the fourth transmitting / receiving unit is equidistant from each of the plurality of second antennas. The detection unit is arranged to be separated from the transmission / reception unit in the second direction, and the detection unit detects the intensity of the signal for each of the plurality of first antennas by the third transmission / reception unit, and the fourth transmission unit The mobile terminal according to appendix 25, wherein the signal intensity is detected for each of the plurality of second antennas by a transmission / reception unit.
(Supplementary note 29) A mobile terminal in which the coordinate input device according to Supplementary note 1 is incorporated.
DESCRIPTION OF SYMBOLS 1, 5, 7 Signal generation part 2 Transmission antenna part 3 Reception antenna 4 Detection part 6 Carrier wave generation part 8 Detection part 10 Finger 10a Left hand 10b Right hand 10c Human body 11, 51 Signal oscillation part 12 Amplifier 13, 14, 60, 70, 90 MUX
41 Amplifier 42 Filter 43 Detector 44 A / D Converter 45 Position Detector 61-63 Receiving Antenna 71-77 Receiving Antenna 100, 500, 600, 700, 900, 1000, 1100 Coordinate Input Device 101, 601, 701, 707 Mobile Terminal 102, 602, 702 Case 103, 603, 703 Touch panel 604, 704 Front surface 605, 705, 708 Side surface 606 Back surface 800 Touch panel 801 Transparent resistance sheet 802 Protrusion 803 Transparent electrode sheet 803
804 to 807 sides 808 to 811 Diode group 812 Power supply 813 Switch 814 Pen 815, 816 Point 817 Detection circuit 900 Touch panel system 910 Touch panel 920 Touch panel controller 911 Sensor 921 Coordinate detection means 922 CPU
923 Operation sensitivity changing means CON1-CON5 Control signal CW Carrier DL Drive line E11, E12 Electrode AMM Ammeter M1, M2 Mixer RS1-RS3, RSd Received signal SIG, SIG1, SIG2 AC signal S1 Oscillator SL Sense line Ts terminal T X1- T X5 terminal T Y1 to T Y5 terminal X1 to X5, Y1 to Y5 Antenna wire
A signal generator for outputting an AC signal;
A first transmission / reception unit having a plurality of first antennas for transmitting and receiving a signal corresponding to the AC signal;
A second transceiver having one or more second antennas for transmitting and receiving the signal to and from the first transceiver;
When the first transmitter / receiver transmits / receives the signal, the signal intensity distribution corresponding to the position of the plurality of first antennas is acquired, and a detection position is detected according to a peak position of the intensity distribution. A detection unit,
The signal generator outputs the AC signal to any one of the plurality of first antennas of the first transceiver.
The signal is transmitted from the plurality of first antennas supplied with the AC signal,
The second transmitting / receiving unit receives the signal with two antennas,
The coordinate input device according to claim 1.
The signal generation unit outputs the AC signal to the second transmission / reception unit,
The signal is transmitted from the second transceiver to the second antenna,
Receiving the signal at any of a plurality of first antennas;
The detection unit receives the signal via a conductor,
The detection position indicates the position of the conductor.
The conductor is a human body.
The coordinate input device according to claim 4.
The detection unit detects one or a plurality of the detection positions according to one or a plurality of the peaks.
The plurality of first antennas are arranged in alignment in a predetermined direction,
The detection unit approximates the intensity of the signal detected for the plurality of first antennas by a polynomial having a position in the predetermined direction as a variable, and determines a position in the predetermined direction where the value of the polynomial is maximum. Detect as the detection position,
The detection unit applies a prediction distribution having the position in the predetermined direction as a variable to the intensity of the signal detected for the plurality of first antennas, and has a maximum correlation with the prediction distribution in the predetermined direction. Detecting a position as the detection position;
The detection unit includes a conductor inserted between the first antenna of the first transmission / reception unit and the second antenna of the second transmission / reception unit based on the intensity of the signal at the detection position. Detecting a distance from the first antenna of the first transceiver unit;
The coordinate input device according to claim 2.
The signal generator outputs a plurality of types of AC signals having different frequencies,
The detection unit detects a position parallel to a plane including the first antenna when the signal generation unit outputs an AC signal having a first frequency, and the signal generation unit detects the first frequency. Detecting a position perpendicular to a plane including the first antenna when an AC signal of a second frequency that is a higher frequency is being output;
The coordinate input device according to claim 9.
The coordinate input device according to claim 10.
The first transmission / reception unit is incorporated in a capacitive touch panel,
All or a plurality of the plurality of first antennas function as electrodes of the capacitive touch panel.
In parallel or independently of position detection of the capacitive touch panel, the signal generator outputs the AC signal to any of the plurality of first antennas of the first transmitter / receiver,
The detection unit detects the detection position by comparing the intensity of the signal detected for each of the plurality of first antennas;
The coordinate input device according to claim 12.
A carrier generation unit that outputs a carrier wave to the signal generation unit and the detection unit;
The signal generator mixes and outputs the AC signal and the carrier wave,
The plurality of first antennas of the first transmission / reception unit transmit the mixed AC signal and the signal corresponding to the carrier wave,
The detection unit detects the intensity of the signal corresponding to the AC signal after removing the carrier wave for each of the plurality of first antennas.
The carrier wave generation unit outputs a carrier wave whose frequency changes with time.
The coordinate input device according to claim 14.
A plurality of the second transmission / reception units;
For each of the plurality of first antennas, a detection position is detected by detecting the intensity of the signal received by the second antenna of any of the plurality of second transmission / reception units, and comparing the detected intensity of the signal. Detect
For each of the plurality of first antennas, a detection position is detected by detecting the intensity of the signal received by the second antenna of any of the plurality of second transmission / reception units, and comparing the detected intensity of the signal. After detecting
For each of the plurality of first antennas, the intensity of the signal received by any one of the second antennas of the other second transmission / reception units among the plurality of second transmission / reception units is detected and detected. Detecting the detection position by comparing the intensity of the signal;
The plurality of first antennas are:
A plurality of first antenna sets aligned in a first direction;
A plurality of second antenna sets aligned in a second direction different from the first direction;
For each antenna of the plurality of first antenna sets, detect the strength of the signal received by the second transmitting / receiving unit, compare the detected signal strength and detect as a first position,
For each of the plurality of second antenna sets, the intensity of the signal received by the second transceiver unit is detected, the detected intensity of the signal is compared and detected as a second position,
Detecting coordinates represented by the first position and the second position as the detection position;
A coordinate input device for detecting the position of a conductor,
When the first transmission / reception unit transmits / receives the signal, the signal acquisition unit obtains an intensity distribution of the signal corresponding to a position of the plurality of first antennas, and determines the first distribution according to a peak position of the intensity distribution. A detection unit that detects a position of the conductor inserted between the plurality of first antennas of the transmission / reception unit and the one or more second antennas of the second transmission / reception unit;
The coordinate input device according to claim 18 is incorporated,
The plurality of first antennas of the first transmission / reception unit are disposed only on the first surface,
Each of the second antennas of the plurality of second transmitting / receiving units is disposed on the first surface or a surface different from the first surface.
JP2013238498A 2013-11-19 2013-11-19 Coordinate input device and mobile terminal Pending JP2015099462A (en)
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