Proximity detection device and hover detection method

Abstract

To provide a proximity detection apparatus and a proximity detection method with improved hover detection sensibility.SOLUTION: A proximity detection apparatus 100 of the present invention includes a detection controller 110 and a touch panel 120. The detection controller 110 includes a drive unit 112 that drives a sensor line on an X side or a Y side, a measurement unit 114 that measures an electrostatic capacity Cm, Cpx, Cpy formed by the sensor line on the X side or the Y side, and a detection unit 116 that performs touch detection or hover detection based on the electrostatic capacity Cm, Cpx, Cpy measured by the measurement unit 114. The drive unit 112 improves a sensibility of the hover detection by changing a frequency of a drive signal that drives the sensor line on the X side or the Y side when performing the hover detection.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present invention relates to a proximity detection device that detects the proximity of an object, and more particularly to a method for detecting the proximity (hover) of an object using a capacitive touch panel. [Background technology]

[0002] The touch panel is mounted in a display unit together with a liquid crystal panel or the like as an input interface for receiving instructions from a user. For example, Patent Documents 1 and 2 disclose capacitive touch sensors. Patent Document 3 discloses a capacitive detection device for detecting the proximity of an operation target, and describes a technology for suppressing a decrease in detection sensitivity due to the influence of a parasitic capacitor. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-8725 [Patent Document 2] Japanese Patent Application Laid-Open No. 2017-182185 [Patent Document 3] International Publication No. WO2018-116706 Summary of the Invention [Problem to be solved by the invention]

[0004] Figure 1 shows an example of a sensor pattern for a capacitive touch panel. The sensor pattern shown in the figure is called a diamond pattern, in which M sensors (Sx1, Sx2, ..., SxM) arranged in the X direction intersect with N sensors (Sy1, Sy2, ..., SyN) arranged in the Y direction. At the intersections, bridges are used to prevent contact between the X and Y sensors. For example, when sensors Syj (j = 1, ..., N) arranged in the Y direction are driven, the system detects a touch operation at the intersection of sensors Sxi and Syj based on the change in capacitance value Cm[i,j] obtained by each sensor Sxi (i = 1, ..., M) arranged in the X direction (commonly referred to as a mutual capacitance method). Figure 1 shows an example in which sensor Sx4 measures the capacitance Cm[4,3] at the intersection when a drive pulse is applied to sensor Sy3. For example, when a finger touches the sensor, the capacitance Cm at that location is measured to decrease.

[0005] In recent years, this sensor pattern has been used to detect the approach of a finger (hover) before touching. The change in capacitance due to hovering is much smaller than the change in capacitance due to touching, so the method of detecting the capacitance at the intersection of sensors Syj and Sxi as described above does not provide sufficient sensitivity. Therefore, for hover detection, as shown in Figure 2, a TP-GND layer parallel to the sensor pattern is placed on the bottom surface, and changes in capacitance Cp between each sensor pattern (Sxi, Syj) and the TP-GND layer are detected. Specifically, the sensor lines Sxi and Syj are driven, and the change in capacitance of the driven sensor line itself is detected (commonly known as the self-capacitance method). For example, when a finger approaches, the capacitance Cp at that position is measured to be larger.

[0006] Figure 3 shows an equivalent circuit in which one sensor is extracted from the sensor pattern of the capacitive touch panel shown in Figure 2, one in the X direction and one in the Y direction. The detection controller 10 applies a drive signal to the sensor line in the X direction or the Y direction, and detects the touch position based on the capacitance Cm measured in the sensor line in the Y direction or the X direction. The detection controller 10 also measures its own capacitance Cpx when the sensor line Sx is driven, measures its own capacitance Cpy when the sensor line Sy is driven, and detects the hover position based on Cpx and Cpy.

[0007] When detecting a touch position, the capacitance Cm[i,j] formed between the sensor lines Sxi and Syj is measured, and when detecting a hover position, the capacitance Cpx[i], Cpy[j] formed between Sxi, Syj and GND, respectively, is measured. Here, Cp (Cpx[i] and Cpy[i]) formed by the entire sensor line and the TP-GND layer is much larger than the capacitance Cm formed at the intersection of the sensor lines. For example, in a typical in-vehicle size touch panel, the capacitance Cp is several hundred pF (picofarad: × 10 -12 On the other hand, the capacitance change of the capacitance Cp due to the hovering of a finger is several tens of fF (femtofarad: × 10 -15 F), so for hover detection, a factor of 1 in 10,000 (10 -4 It was necessary to detect volume changes of the order of 1000, making accurate detection difficult.

[0008] Therefore, to improve the hover detection sensitivity, there is a method of driving the TP-GND layer with the same sine wave as the sensor line Sxi or Syj. The figure shows the state in which the sensor line Syj is being detected, and the detection controller 10 drives the sensor line Syj and the TP-GND layer with a sine wave. When detecting the sensor line Sxi, the sensor line Sxi and the TP-GND layer are driven with the same sine wave.

[0009] With this driving method, both ends of Cpy[j] are driven with the same waveform, which cancels out the effect of the parasitic capacitance Cpy[j] in the measurement results, and ideally, only the capacitance change due to the proximity of a finger is detected. However, in reality, the electrical characteristics of the paths along which the two sine waves reach both ends of Cpy[j] are different, so the waveforms applied to both ends of Cpy[j] do not match perfectly, and Cpy[j] cannot be completely canceled out. Nevertheless, the apparent Cp value can be reduced to several pF, and the capacitance change of several tens of fF (femtofarads) due to hovering can be reduced to one hundredth (10 -2 ) order of magnitude.

[0010] 4 is a timing diagram of the drive / measurement when performing hover detection and touch detection. As shown in the figure, the detection controller 10 detects Cpx[i], Cpy[j], and Cm[i,j] in one cycle in a time-division manner. However, it is also possible to alternately perform Cpx and Cpy detection once every two cycles.

[0011] In a hover detection method in which the sensor line and the TP-GND layer are driven with the same sine wave, considering the pattern wiring in an actual touch panel, for example, as shown in Figure 5, a connector 20 is placed below the screen of the display, and the TP-GND line is electrically connected only below the TP-GND layer via the connector 20. If the entire periphery of the TP-GND layer could be connected to the TP-GND line, a stronger TP-GND layer could be realized, but this would increase the wiring area of ​​the sensor and TP-GND patterns, causing design problems such as making it impossible to achieve a narrow frame on the display screen. Therefore, the connector 20 is connected below the TP-GND layer.

[0012] Considering that the top sensor line Sy1 and the bottom sensor line SyN of the screen measure the capacitances Cpy[1] and Cpy[N] formed between them and the TP-GND layer, respectively, the TP-GND line used to measure Cpy[1] runs from connector 20 through a large portion of the TP-GND layer to Cpy[1]. The TP-GND layer is typically made of a thin, transparent material such as ITO, and has a significant surface resistance. Therefore, the drive signal from the TP-GND layer used to measure Cpy[1] is attenuated more than the drive signal used to measure Cpy[N] due to the RC filter defined by this surface resistance and parasitic capacitance.

[0013] In this way, the attenuation of the drive signal on the TP-GND layer differs depending on the position on the screen in the Y direction, which increases the difference between the drive signal on the upper sensor line and the drive signal on the TP-GND layer, resulting in an apparent Cp value that differs for each sensor line in the Y direction, as shown in Figure 6. On the other hand, because the change in capacitance due to the approach of a finger is constant regardless of the position on the screen, the sensitivity of hover detection at the top of the screen is worse than that at the bottom, resulting in differences in hover detection sensitivity depending on the location on the screen.

[0014] The present invention aims to solve the above-mentioned conventional problems and to provide a proximity detection device and a hover detection method that improve the sensitivity of hover detection. [Means for solving the problem]

[0015] A proximity detection device according to the present invention includes a touch panel including a plurality of sensor lines on an X side, a plurality of sensor lines on a Y side intersecting the plurality of sensor lines on the X side, a planar GND layer arranged to face the sensor lines on the X side and the Y side, and connection means electrically connected to a selected position on the GND layer; and detection means that detects an object hovering (approaching) over the touch panel based on a change in capacitance formed between the selected sensor line on the X side or the Y side and the GND layer, wherein, when performing hover detection, the detection means applies a drive signal to the selected sensor line on the X side or the Y side, and applies a drive signal having the same waveform as the drive signal to the GND layer via the connection means, and further the detection means changes the frequency of the drive signal according to the position of the selected sensor line.

[0016] In one embodiment, the detection means applies a drive signal having a frequency lower than that of a drive signal applied to a sensor line farther from the connection means than to a sensor line closer to the connection means. In another embodiment, the detection means selects a predetermined number of sensor lines from among the plurality of sensor lines and simultaneously applies the drive signal to the selected sensor lines. In another embodiment, when the connection means is connected to the upper or lower side of a rectangular GND layer, the detection means changes the frequency of the drive signal applied to the sensor line extending parallel to the upper or lower side. In another embodiment, when the connection means is connected to the left or right side of the rectangular GND layer, the detection means changes the frequency of the drive signal applied to the sensor line extending parallel to the left or right side. In another embodiment, in addition to hover detection, the detection means detects a touch on the touch panel based on a change in capacitance formed at the intersection of an X-side sensor line and a Y-side sensor line. In one embodiment, the detection means performs hover detection using an X-side sensor line, hover detection using a Y-side sensor line, and touch detection using the X-side and Y-side sensor lines during one cycle. In one embodiment, the drive signal is a sine wave.

[0017] The hover detection method according to the present invention is for a proximity detection device including a touch panel including a plurality of X-side sensor lines, a plurality of Y-side sensor lines intersecting the X-side sensor lines, a planar GND layer arranged to face the X-side and Y-side sensor lines, and a connection means electrically connected to a selected position on the GND layer. The method applies a drive signal to the selected X-side or Y-side sensor line, and applies a drive signal having the same waveform as the drive signal to the GND layer via the connection means. The frequency of the drive signal is changed depending on the position of the selected sensor line, and the hover of an object over the touch panel is detected based on a change in capacitance formed between the selected X-side or Y-side sensor line and the GND layer. In one embodiment, the frequency of the drive signal applied to the sensor line farther from the connection means is lower than the frequency of the drive signal applied to the sensor line closer to the connection means. [Effects of the Invention]

[0018] According to the present invention, when performing hover detection, the frequency of the drive signal is changed depending on the position of the selected sensor line, so that the apparent capacitance of the measured sensor line can be reduced, thereby improving the sensing accuracy of hover detection. [Brief explanation of the drawings]

[0019] [Figure 1] FIG. 2 is a plan view showing an example of a sensor pattern of a capacitive touch panel. [Figure 2] FIG. 1 is a perspective view showing a sensor structure for detecting hover on a touch panel. [Figure 3] FIG. 1 is a diagram showing an equivalent circuit of a capacitive touch panel. [Figure 4] FIG. 10 is a diagram illustrating the timing of hover detection and touch detection on a capacitive touch panel. [Figure 5] 10 is a diagram illustrating the electrical connection of the TP-GND layer when a touch panel is mounted on a display unit. FIG. [Figure 6]1A and 1B are diagrams illustrating problems with conventional capacitive touch panels. [Figure 7] 1 is a diagram showing the configuration of a capacitance-type proximity detector according to a first embodiment of the present invention. [Figure 8] 10A and 10B are diagrams illustrating drive waveforms when the sensor line Syj is driven by the self-capacitance method. [Figure 9] FIG. 4 is a diagram illustrating an example of control of the drive frequency for each sensor line according to the first embodiment of the present invention. [Figure 10] 4 is a graph showing apparent Cp values ​​for each sensor line according to the first embodiment of the present invention. [Figure 11] FIG. 10 is a diagram illustrating the configuration of a proximity detection device according to a second embodiment of the present invention. [Figure 12] FIG. 10 is a diagram illustrating an example of controlling the drive frequency for each sensor line according to the second embodiment of the present invention. [Figure 13] 10 is a graph showing apparent Cp values ​​for each sensor line according to the second embodiment of the present invention. [Figure 14] FIG. 10 is a perspective view showing a sensor structure of a touch panel according to a third embodiment of the present invention. [Figure 15] FIG. 10 is a diagram illustrating an example of controlling the drive frequency for each sensor line according to the third embodiment of the present invention. [Figure 16] 10 is a graph showing apparent Cp values ​​for each sensor line according to the third embodiment of the present invention. [Figure 17] FIG. 10 is a diagram illustrating an example of controlling the drive frequency for each sensor line according to the fourth embodiment of the present invention. [Figure 18] FIG. 10 is a diagram showing the timing of hover detection and touch detection according to a fourth embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0020] Next, an embodiment of the present invention will be described. A proximity detection device according to the present invention includes a capacitive touch panel and detects the hover (approach) or contact of an operation target (for example, an object such as a user's finger). The proximity detection device according to the present invention is mounted on a display such as a liquid crystal panel, and provides a display device or display unit equipped with a user interface function, although it is not particularly limited thereto. Such display devices are used, for example, in-vehicle devices, multi-function mobile phones (smartphones), portable information terminals (tablet computers, laptop computers, notebook computers), etc. [Example]

[0021] Next, an embodiment of the present invention will be described with reference to the drawings. Fig. 7 is a block diagram showing the configuration of a proximity detection device according to an embodiment of the present invention. The proximity detection device 100 includes a capacitive touch panel 110 and a detection controller 120 that detects hover (approach) or touch (contact) of an operation target on the touch panel 110.

[0022] The touch panel 120 is configured to include, for example, M sensor lines (Sx1, Sx2...SxM) arranged in the X direction and N sensor lines (Sy1, Sy2, ..., SyN) arranged in the Y direction, which are called a diamond pattern as shown in FIG. 1, a roughly rectangular TP-GND layer 122 arranged below and facing the pattern of these sensor lines, and a connector 124 for electrically connecting the TP-GND layer 122 and the detection controller 120.

[0023] The TP-GND layer 122 is formed, for example, from a transparent metal material (e.g., ITO) in a generally rectangular shape and formed on a substrate such as glass or plastic. A connector 124 is attached to the bottom of the TP-GND layer 122, and the connector 124 electrically connects a signal line from the detection controller 110 to the TP-GND layer 122. The touch panel 120 is mounted, for example, on a liquid crystal panel (not shown), and provides a user input interface related to images displayed on the liquid crystal panel.

[0024] The detection controller 110 controls the overall operation of the touch panel 120. The detection controller 110 includes a drive unit 112 for driving each of the X-side sensor lines Sx or the Y-side sensor lines Sy, a measurement unit 114 for measuring the capacitances Cm, Cpx, and Cpy of each of the X-side sensor lines Sx or the Y-side sensor lines Sy, and a detection unit 116 for detecting a touch position of an operation target on the touch panel 120 based on a change in the capacitance Cm measured by the measurement unit 114, and for detecting a hover position based on the changes in the capacitances Cpx and Cpy.

[0025] The driving unit 112 includes an AC voltage generating unit for driving the sensor line on the X side or Y side and the TP-GND layer 122 with a sine wave when performing hover detection. The sine wave applied as a driving signal to the sensor line on the X side or Y side and the TP-GND layer 122 has the same frequency, gain, and phase. As will be described later, the driving unit 112 changes the frequency of the sine wave generated by the AC voltage generating unit depending on the position of the sensor line.

[0026] 4, for example, during one cycle, the detection controller 110 measures the capacitance Cpx of the X-side sensor line itself and the capacitance Cpy of the Y-side sensor line itself, detects a hover based on the change in capacitance, and further measures the capacitance Cm of the intersection of the X-side sensor line Sx and the Y-side sensor line Sy, and detects a touch based on the change in capacitance. In touch detection, it is assumed that the drive unit 112 drives the Y-side sensor line Sy and the measurement unit 114 measures the capacitance Cm from the X-side sensor line Sx. However, it is also possible to drive the X-side sensor line Sx and measure the capacitance Cm from the Y-side sensor line Sy.

[0027] In this embodiment, when performing hover detection, the driving frequency of the sine wave for driving each of the sensor lines Sy is changed for each sensor line in accordance with the electrical characteristics of each path from the connector 124 to the sensor line Sy.

[0028] 8 illustrates sine waves that drive the sensor line Sy and the TP-GND when measuring the capacitance Cpy. When the sensor line Sy is driven with a sine wave of the same frequency, the resistance of the TP-GND layer 122 increases as the distance from the connector 124 increases, and the cutoff frequency of the RC filter decreases (cutoff frequency = 1 / 2πRC). Therefore, when the frequency of the sine wave is greater than the cutoff frequency, the attenuation of the sine wave increases on the upper side of the TP-GND layer 122.

[0029] 9, the frequency of the sine wave used to drive the upper sensor line (Sy1 side) is set lower than that used to drive the lower sensor line (SyN side), thereby suppressing attenuation of the sine wave on the upper side of the TP-GND layer 122. The frequency of the sine wave is adjusted appropriately depending on the electrical characteristics of the TP-GND layer 122 and electrical measurements of the X- and Y-side sensor lines. If the frequency of the sine wave is lower than the cutoff frequency, the attenuation of the sine wave on the upper side of the TP-GND layer 122 can be reduced to approximately zero, minimizing the difference between the sine wave of the sensor line and the sine wave of the TP-GND layer 122 and reducing the apparent parasitic capacitance Cpy.

[0030] Specifically, when measuring the capacitance Cpy of the sensor line Sy in the Y direction, the driver 112 gradually increases the frequency F of the sine wave sequentially applied from the sensor line Sy1 to the sensor line SyN, or gradually decreases the frequency F of the sine wave sequentially applied from the sensor line SyN to the sensor line Sy1. At this time, a sine wave with the same frequency as that of the sensor line Sy is applied to the TP-GND layer 122.

[0031] As described above, when measuring Cpy of the upper sensor line Sy, the effect of the resistance R of the TP-GND layer 122 becomes greater and the cutoff frequency of the RC filter for the drive signal of the TP-GND layer 122 becomes lower (i.e., the amount of attenuation becomes greater for signals of the same frequency), but by lowering the operating frequency of the sine wave, the amount of attenuation decreases and the difference in the waveform of the sine wave between the sensor line Sy at both ends of the capacitance Cpy and the TP-GND layer 122 becomes smaller, and as a result, the difference in apparent Cp measured on the upper and lower sides of the touch panel 120 can be reduced, as shown in Fig. 10. This makes it possible to reduce the difference in sensitivity for each sensor line in the Y direction, i.e., the difference in sensitivity of hover detection depending on the position on the touch panel 120.

[0032] Next, a second embodiment of the present invention will be described. While the first embodiment shows an example in which each sensor line is driven at a separate frequency, the detection controller of the second embodiment has multiple internal drive units and measurement units, and simultaneously measures changes in the capacitance of multiple sensor lines.

[0033] FIG. 11(A) shows an example of measuring the capacitance Cpy of a sensor line Sy, in which the detection controller 110 has, for example, six internal driving units / measuring units 140-1, 140-2, ..., 140-6, and the driving units / measuring units 140-1 to 140-6 are simultaneously connected to each of the six sensor lines Sy selected by a selection circuit (multiplexer MUX) 150.

[0034] When the sensors of the sensor line Sy1...SyN are divided into k blocks, as shown in Figure 11(B), the driving units / measurement units 140-1 to 140-6 are connected sequentially in a time-division manner to each block of the sensor line [Sy1...Sy6], [Sy7...Sy12], [Sy13...Sy18]...[Sy(6k-5)...SyN] via the selection circuit 150.

[0035] In this embodiment, the sine wave driving frequency for driving each block is controlled so that it is lower on the top side than on the bottom side, as shown in Figure 12. The six sensor lines within each block are driven at the same frequency (i.e., a common AC voltage generation circuit is used). Even in this case, the operating frequency of each block is determined according to the average or maximum resistance R of the sensor within the block, thereby reducing the difference in capacitance Cp between sensor lines, as shown in Figure 13. Furthermore, although the change in Cp value is not smooth at the block boundary (for example, the boundary between sensor line Sy6 and sensor line Sy7), this is not important. In order to improve the sensitivity difference in hover detection, it is important to lower the capacitance Cp overall and make it uniform.

[0036] Next, a third embodiment of the present invention will be described. In the first and second embodiments, the connector 124 was disposed at the center of the lower side of the TP-GND layer 122, but in the third embodiment, as shown in Fig. 14, the connector 126 is attached to the center of the right side of the TP-GND layer 122. In this configuration, differences in the electrical paths from the connector 126 to the X-side sensor lines Sx[1...M] cause changes in the capacitance Cp in measurements on each sensor line Sx.

[0037] Therefore, in the third embodiment, as shown in Fig. 15, the drive frequency of the left sensor line (Sx1 side) is set to a lower value than that of the right sensor line (SxM side), thereby reducing the attenuation of the measurement signal on the left sensor line, as in the first and second embodiments. This makes it possible to reduce the difference in apparent Cp values ​​measured on the right and left sensor lines, as shown in Fig. 16, which means that the sensitivity difference between the sensor lines on the X side is reduced.

[0038] In the first and second embodiments, the connector 124 is attached to the center of the bottom side (SyN side) of the TP-GND layer 122, but if the connector 124 is attached to the center of the top side (Sy1 side) of the TP-GND layer 122, the same effect can be obtained by setting the drive frequency of the sensor line on the bottom side to a lower value than that on the top side. Also, in the third embodiment, the connector 126 is attached to the center of the right side (SxM side) of the TP-GND layer 122, but if the connector 126 is attached to the center of the left side (Sx1 side) of the TP-GND layer 122, the same effect can be obtained by setting the drive frequency of the sensor line on the right side to a lower value than that on the left side.

[0039] Next, a fourth embodiment of the present invention will be described. When the number of measurement means in the detection controller 110 is greater than the number of sensors (M, N), blocking as in the second embodiment is unnecessary. However, as shown in FIG. 4, the X-side sensors (Sx[1...M]) and the Y-side sensors (Sy[1...N]) must be driven at different times to measure Cpx[1...M] and Cpy[1...N]. In this case, due to differences in the electrical paths leading to the TP-GND layer, the Cpx of the X-side sensors and the Cpy of the Y-side sensors measured when the drive frequency is changed have different frequencies at which the Cpx and Cpy values ​​become minimum, as shown in FIG. 17. In the figure, / Cpx[i] and / Cpy[j] are the average values ​​of all sensor lines Sx and Sy.

[0040] In this embodiment, by utilizing such frequency characteristics, the detection sensitivity of the X-side sensors Sx and the Y-side sensors Sy can be improved by selecting different drive frequencies suitable for the X and Y sides during hover detection, such as frequency Fx0 for the X-side sensors Sx[1...M] and frequency Fy0 for the Y-side sensors Sy[1...N], as shown in Fig. 18. Furthermore, in this embodiment, the drive frequency for the X side and the drive frequency for the Y side are fixed, respectively, which makes it possible to simplify the configuration of the drive unit 112 of the detection controller 110.

[0041] As described above, according to this embodiment, by changing the drive frequency for each sensor line according to the electrical characteristics, the apparent parasitic capacitance measured for each sensor line can be reduced, thereby improving and stabilizing the hover detection sensitivity.

[0042] In the above embodiment, a sine wave is used as the drive signal, but the present invention is not limited to this and a square wave may be used as the drive signal. However, a sine wave has an advantage in terms of EMI countermeasures because it generates less radiated noise than a square wave.

[0043] Furthermore, in the above embodiment, an example was shown in which hover detection and touch detection were performed in a time-division manner during one cycle, but this is not limited to this, and the present invention may perform only hover detection using a capacitive touch panel, or hover detection and touch detection may be performed in separate cycles.

[0044] Although the preferred embodiments of the present invention have been described in detail above, the present invention is not limited to the specific embodiments, and various modifications and changes are possible within the scope of the gist of the invention described in the claims. [Explanation of symbols]

[0045] 100: Proximity detection device 110: Detection controller 120: Touch panel 122: TP-GND layer 124, 126: Connector 140: Drive unit / measurement unit 150: Selection circuit

Claims

1. a touch panel including a plurality of sensor lines on an X side, a plurality of sensor lines on a Y side intersecting the plurality of sensor lines on the X side, a planar GND layer disposed so as to face the sensor lines on the X side and the Y side, and a connection means electrically connected to a selected position of the GND layer; a detection means for detecting a hover (approach) of an object on the touch panel based on a change in capacitance formed between a selected sensor line on the X side or Y side and the GND layer, When performing hover detection, the detection means applies a drive signal to a selected X-side or Y-side sensor line, and applies a drive signal having the same waveform as the drive signal to the GND layer via the connection means, and the detection means makes the frequency of the drive signal applied to the sensor line farther from the connection means smaller than the frequency of the drive signal applied to the sensor line closer to the connection means.

2. 2. The proximity detection device according to claim 1, wherein said detection means selects a predetermined number of sensor lines from among a plurality of sensor lines, and applies said drive signal to the selected sensor lines simultaneously.

3. 3. The proximity detection device according to claim 1, wherein when the connection means is connected to the upper or lower side of a rectangular GND layer, the detection means changes the frequency of a drive signal applied to a sensor line extending parallel to the direction of the upper or lower side.

4. 3. The proximity detection device according to claim 1, wherein when the connection means is connected to the left or right side of the rectangular GND layer, the detection means changes the frequency of the drive signal applied to the sensor line extending parallel to the left or right direction.

5. 5. The proximity detection device according to claim 1, wherein the detection means detects a touch on the touch panel based on a change in capacitance formed at an intersection of an X-side sensor line and a Y-side sensor line in addition to hover detection.

6. The proximity detection device according to claim 5 , wherein the detection means performs hover detection using an X-side sensor line, hover detection using a Y-side sensor line, and touch detection using the X-side and Y-side sensor lines during one cycle.

7. The proximity detection device according to claim 1 , wherein the drive signal is a sine wave.

8. A proximity detection device according to any one of claims 1 to 7; a display panel on which the touch panel is mounted; A display device comprising:

9. A detection method for a proximity detection device including a touch panel including a plurality of sensor lines on an X side, a plurality of sensor lines on a Y side intersecting the plurality of sensor lines on the X side, a planar GND layer disposed so as to face the sensor lines on the X side and the Y side, and a connection means electrically connected to a selected position of the GND layer, applying a drive signal to a selected sensor line on the X side or Y side, and applying a drive signal having the same waveform as the drive signal to the GND layer via the connection means, and making the frequency of the drive signal applied to the sensor line farther from the connection means lower than the frequency of the drive signal applied to the sensor line closer to the connection means; A detection method for detecting an object hovering over the touch panel based on a change in capacitance formed between a selected sensor line on the X side or Y side and the GND layer.

10. The detection method described in Claim 9, further comprising, in addition to hover detection, detecting a touch on the touch panel based on a change in capacitance formed at the intersection of an X-side sensor line and a Y-side sensor line.

11. The detection method described in claim 10, wherein hover detection is performed by the X-side sensor line, hover detection by the Y-side sensor line, and touch detection by the X-side and Y-side sensor lines during one cycle.

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