JP5637492B2 - Capacitive touch panel device - Google Patents

Description

  The present invention relates to a capacitive touch panel device used in a car navigation device or the like mounted on a vehicle (for example, an automobile).

  In many cases, a display such as a car navigation device of a vehicle is a capacitive touch panel device that is operated by the operator with a finger in consideration of the convenience of the operator. The capacitance type touch panel device includes a touch panel on which a switch such as a slider is displayed, and a transparent electrode panel provided with a plurality of electrodes corresponding to the switch and arranged in an overlapping state with the touch panel. The wiring extended from each electrode is provided by printing on the electrode panel, and is connected to a circuit board constituting the touch panel device. When the operator places a finger on the switch portion displayed on the touch panel, the capacitance of the electrode arranged at the contact portion changes. When the control means detects the change in capacitance at this time, it is determined that the operator has operated the switch. As a prior art of a capacitive touch panel device, there is one disclosed in Patent Document 1.

  In the case of a capacitive touch panel device, compared to a resistive touch panel device, the switch is operated only by touching the operator's finger (in other words, the operator does not press the finger). This has the advantage that it can be determined and the transparency of the electrode panel can be increased.

  However, in the case of an electrostatic capacitance type touch panel device, when an operator wears a glove and operates, for example, the detection accuracy of the capacitance change is lowered. In order to prevent this, if the detection sensitivity of the touch panel device is increased, the switch part touches when the operator touches the part other than the switch with bare hands (especially when the part of the wiring extending from the electrode is touched). There is a risk of misrecognizing that it has been performed and causing malfunction.

  In order to prevent this problem, a technique of a capacitive touch panel operating glove has been disclosed (see Patent Document 2). However, it is difficult to require the operator to use these gloves.

Japanese Patent No. 4260198 JP 2008-81896 A

  SUMMARY OF THE INVENTION In view of the above-described problems, the present invention aims to make it difficult for an operator to operate erroneously even when the operator operates a part other than the switch displayed on the touch panel in the capacitive touch panel device. It is said.

The present invention for solving the above problems is as follows.
A touch panel on which switches that are operated by an operator touching a finger are displayed;
Provided in an overlapping state with the touch panel, a plurality of electrodes are arranged side by side so as to correspond to the switch, and the wiring extending from one of the adjacent electrodes is in the direction in which the electrodes are arranged An electrode panel arranged to extend in one area divided into two and the wiring extending from the other electrode is also arranged to extend in the other area ;
Detecting means for detecting the capacitance of each of the electrodes when the operator's finger touches the touch panel;
It is a value that changes according to each capacitance detected by the detection means, and becomes larger than a preset reference value when the operator's finger is touching the electrode placement portion of the touch panel, Calculating means for calculating a finger value, which is a value smaller than the reference value when a finger touches the wiring arrangement portion of the touch panel, using each capacitance detected by the detecting means;
A control unit that determines whether or not an operator's finger is touching a switch portion of the touch panel based on a comparison between the finger value calculated by the calculation unit and the reference value;
It is characterized by providing.

  According to the configuration of the present invention, the wirings extending from the electrodes are alternately extended in the region divided in two by the electrode arrangement direction. Then, the capacitance value when the operator's finger touches the switch portion (that is, the portion where the electrode is disposed) is increased, and the capacitance when the wiring portion is touched. To reduce the value of. By comparing this value with a reference value set in advance by the control unit, it is possible to determine whether or not the operator's finger is touching the switch portion of the touch panel. For this reason, an erroneous operation of the operator can be surely prevented. Further, as compared with the conventional electrode panel, it is only necessary to change the arrangement of the wiring extending from the electrode and the algorithm for calculating the capacitance value.

Specifically, the capacitance D [n] (n is arranged side by side) of an electrode (hereinafter referred to as a “specific electrode”) that is arranged at a contact portion of the touch panel with the operator's finger or a source of wiring. The order of capacitance from one end of the arranged electrode is shown), and the capacitance of the electrode adjacent to the specific electrode is D [n−1], D [n + 1], and they are on the side opposite to the specific electrode side. When the capacitance of adjacent electrodes is D [n−2], D [n + 2], and α and β are coefficients ,
The calculation means uses the finger value fv as fv = (α × D [n] + D [n−1] + D [n + 1]) − (D [n−2] + D [n + 2] + β × D [others] ) ( However, the capacitance D [n] = 0 of the nonexistent electrode is calculated )
The control unit validates an operation in which the operator's finger touches the touch panel when the finger value fv is larger than a preset reference value, and invalidates the operation when the finger value fv is equal to or less than a reference value. To do.

  At this time, when there are a plurality of electrodes or wirings arranged at the contact portion between the operator's finger and the touch panel, the specific electrode having the maximum capacitance generated by the contact with the finger is defined as the specific electrode.

  The coefficients α and β are determined by the size of the electrode and / or the wiring pattern. For example, the coefficient α is 2 and the coefficient β is 4. However, other values may be used.

  The switch can be provided in a linear shape, a curved shape, or a shape including them. Thereby, while being able to implement this invention in various parts, a design can be made novel.

It is a front view of the touch panel apparatus 100 of the Example of this invention. 4 is an exploded perspective view of the touch panel device 100. FIG. 2 is a plan view of an electrode panel 5. FIG. 4 is a block diagram of the touch panel device 100. FIG. (A) is a schematic view of a state where the operator's finger F touching the portion of the electrode S ₈ of the slider 13, (b) is an algorithm for calculating the fingers value fv at that time. (A) is a schematic diagram in a state where the operator's finger F is touching the wirings T _{2 to} T ₁₀ , and (b) is an algorithm for calculating the finger value fv at that time. 5 is a flowchart showing the operation of the touch panel device 100. It is a schematic diagram which shows arrangement | positioning of the electrode Sn and wiring Tn in the slider 38 used as V shape. FIG. 4 is a schematic diagram showing an arrangement of electrodes Sn and wirings Tn in the rotary slider 14. It is a top view of the electrode panel 39 in which the sliders 41 and 42 were provided in two places.

  Hereinafter, embodiments of the present invention will be described in detail.

  1 is a front view of a capacitive touch panel device 100 (hereinafter simply referred to as “touch panel device”) and a car navigation device 200 according to an embodiment of the present invention, and FIG. 2 is an exploded perspective view of the touch panel device 100. 3 is a front view of the electrode panel 5, and FIG. 4 is a block diagram of the touch panel device 100.

  As shown in FIG. 1, a touch panel device 100 and a car navigation device 200 disposed above the touch panel device 100 are attached to the front panel of the automobile. The car navigation apparatus 200 includes a display 1 and a plurality of push button switches 2 and a rotary switch 3 arranged on both sides thereof.

  The touch panel device 100 is for operating an in-vehicle air conditioner (not shown). As shown in FIG. 2, the touch panel device 100 corresponds to the touch panel 4 on which various switches visually recognized by the operator are displayed and the touch panel 4 switches. A transparent electrode panel 5 in which a plurality of electrodes and wiring extending from the electrodes are provided by means such as printing, a touch panel 4 and a bezel 6 for holding the electrode panel 5, a support panel 7, a circuit board 8, and a temperature. A liquid crystal panel 9 for displaying and a case body 11 for holding them are provided.

  The touch panel 4 will be described. As shown in FIG. 1, a temperature display unit 12 for displaying a set temperature of an air conditioner on a liquid crystal display is provided almost at the upper part of the center of the touch panel 4 of the present embodiment, and a slider for adjusting the air volume below the temperature display unit 12. 13 is provided. A rotary slider 14 for adjusting the temperature is provided on the left side of the touch panel 4, and when the operator touches a clockwise (clockwise) arrow 14 a, the set temperature rises, and the counterclockwise (counterclockwise) direction When the arrow 14b is touched, the set temperature decreases. Further, on the right side of the touch panel 4, a touch switch 15 for turning on / off the air conditioner, a touch switch 16 for sending warm air to the front window of the vehicle, a touch switch 17 for sending warm air to the rear window of the vehicle, an outside air introduction mode, A touch switch 18 for selecting a room air circulation mode is provided.

  Next, the electrode panel 5 will be described. As shown in FIG. 3, the electrode panel 5 of the present embodiment is made of a thin plate of resin (for example, polyethylene terephthalate (PET) or polyimide), and a portion where the liquid crystal panel 9 is arranged is cut out. A plurality of (six in the case of this embodiment) electrodes 19 that are wavy (zigzag) in the vertical direction (vertical direction) are arranged side by side in the horizontal direction (horizontal direction). . In the rotary slider 14, a plurality of electrodes 21 (12 in this embodiment) divided in the circumferential direction are arranged side by side on the circumference. In addition, sheet-like electrodes 22 to 25 corresponding to the touch switches 15 to 18 are arranged in the portions of the touch switches 15 to 18. Wirings 26, 27, 28, 29, 31 and 32 are extended from the respective electrodes 19, 21, 22 to 25. In the electrode panel 5, a diagonal grid-like GND mesh (not shown) is provided in a portion other than the portion where the electrodes 19, 21, and 22 are disposed. Note that reference numerals 33 and 34 in FIG. 3 denote connection protrusions for connecting the electrode panel 5 and the circuit board 8.

  As shown in FIG. 4, the touch panel 4 and the electrodes 19, 21, 22 to 25 are connected to the control unit 35. The control unit 35 is mainly composed of a microcomputer including a well-known CPU, ROM, RAM, I / O (not shown) and a bus line for connecting them, and is stored in a storage unit such as a ROM or an external storage device 36. Various controls (processing such as calculation of capacitance, calculation of finger value fv, which will be described later, and comparison with a reference value) are executed based on the stored program. The result of this process is output to the drive unit 37 (in this embodiment, an air conditioner).

  Next, an algorithm for calculating the capacitance of the electrode 15 provided on the slider 13 in the electrode panel 5 of the present embodiment will be described with reference to the schematic diagram of FIG. 5 and the flowchart of FIG.

  In FIG. 5A, ten electrodes are arranged in the horizontal direction, and wiring is extended from each electrode. In the electrode panel 5 of the present embodiment, the wiring from each electrode extends alternately in a region that bisects the electrode panel 5 in the arrangement direction P of each electrode. 10 electrodes are numbered 1, 2, 3,... 10 in order from the left end, and each electrode is described as Sn (n is any one of 1 to 10) and extended from each electrode. The provided wiring is described as Tn (n is any one of 1 to 10).

  When the operator touches the finger F with a predetermined portion of the electrode panel 5 (the portion where the electrode Sn or the wiring Tn is disposed) via the touch panel 4, capacitance is generated at the contact portion with the finger F and its peripheral portion. To do. This is because when the finger F touches the electrode Sn or the wiring Tn, the capacitance is distributed (continuously) from the electrode Sn to the wiring Tn. Here, the capacitance generated when the operator's finger F touches the electrode Sn is described as D [n]. Note that when the operator's finger F touches the wiring Tn, the capacitance generated in the electrode Sn as a source thereof is defined as D [n]. Hereinafter, when the operator touches the finger F and there are a plurality of electrodes Sn or wirings Tn in which the electrostatic capacitance D [n] is generated, the electrode Sn that generates the largest electrostatic capacitance D [n] is selected. One is selected and described as “specific electrode Sn”.

The capacitances of the pair of electrodes S _n−1 and S _{n + 1} adjacent to the specific electrode Sn are D [n−1] and D [n + 1], and are adjacent to the specific electrode Sn on the opposite side. When the capacitances of the pair of electrodes S _n−2 and S _{n + 2} are D [n−2] and D [n + 2], and α and β are coefficients, the finger value fv is fv = (α × D [n]. + D [n−1] + D [n + 1]) − (D [n−2] + D [n + 2] + β × D [others]). However, the capacitance D [n] of the electrode Sn that does not exist is set to zero. The first term of this equation represents the sum of the capacitances D [n], D [n−1], and D [n + 1] of the specific electrode Sn and the pair of electrodes S _n−1 and S _{n + 1} adjacent to the specific electrode Sn. Are the capacitances D [n−2] and D [n + 2] of a pair of electrodes S _n−2 and S _{n + 2} that are adjacent to each other from the specific electrode Sn, and those (the specific electrode Sn and the pair of electrodes _{Sn−). 1} , S _{n + 1,} and a pair of capacitances D [others] other than the pair of electrodes S _n−2 , S _{n + 2} ).

First, the finger value fv when the operator's finger F is touching the electrode Sn will be described. Since the electrodes Sn are arranged in the horizontal direction, the capacitances D [n], D [n−1], D [n + 1] of the specific electrode Sn and a pair of electrodes S _n−1 and S _{n + 1} adjacent to the specific electrode Sn. ] Are large, and their sum (previous term) is also large. Then, the electrostatic capacitances D [n−2] and D [n + 2] of a pair of electrodes S _n−2 and S _{n + 2} adjacent to one specific electrode Sn and the electrostatic capacitances D [others] of the other electrodes. Exists at a position away from the operator's finger F, so that their sum is small. As a result, the finger value fv shows a large value.

Specifically, as shown in (a) of FIG. 5, when the operator's finger F touching the electrode S _8, there is a case touching the electrode S _7, S ₉ simultaneously. The coefficient α is 2 and the coefficient β is 4. The finger value fv at this time is fv = (2 × D [8] + D [7] + D [9]) − (D [6] + D [10] + 4 ×, as shown in FIG. 5B. D [1-5]). The electrostatic capacitances D [8], D [7], D [9] in the previous term of this equation are large because they are arranged immediately below the finger F, and the electrostatic capacitances D [6], D [10] in the subsequent term are large. , D [1-5] are small because they are arranged away from the finger F. As a result, the finger value fv shows a large value.

Next, the finger value fv when the operator's finger is touching the wiring Tn will be described. As shown in FIG. 6A, the wirings Tn from the respective electrodes Sn are alternately arranged in regions divided by the arrangement direction P of the respective electrodes Sn, so that the capacitance D of the specific electrode Sn. Although [n] increases, the electrostatic capacitances D [n], D [n−1], and D [n + 1] of the pair of electrodes S _n−1 and S _{n + 1} adjacent thereto are all small (previous item). Then, electrostatic capacitances D [n−2], D [n + 2], D [others] of a pair of electrodes S _n−2 and S _{n + 2} that are adjacent to each other from the specific electrode Sn and other electrodes. Are located close to the operator's finger, so their sum is large (the latter term). As a result, the finger value fv becomes small.

Specifically, as shown in FIG. 6A, the operator's finger F may touch the wirings T ₂ , T ₄ , T ₆ , T ₈ , and T ₁₀ of the electrode S _{8 at} the same time. . The coefficient α is 2 and the coefficient β is 4. In addition, the electrode that generates the largest capacitance at this time is D [8]. The finger value fv at this time is fv = (2 × D [8] + D [7] + D [9]) − (D [6] + D [10] + 4 ×, as shown in FIG. 6B. D [1-5]). The preceding capacitance D [8] of the formula is greater since the wiring _{T 8} are arranged directly below the finger F, the capacitance D [7], D [10 ] is the wiring _T 7, _{T 9} Since it is arranged in a region far from the finger F, it is small. Further, the electrostatic capacitances D [6], D [10], and D [1 to 5] in the latter term are large because the wirings T ₂ , T ₄ , T ₆ , and T ₁₀ are arranged immediately below the finger F. . As a result, the finger value fv shows a small value.

  The operation of determining whether or not the finger of the operator has touched the electrode Sn when calculating the finger value fv by the above algorithm will be described with reference to the flowchart of FIG.

  First, it is determined whether or not the operator's finger F has touched the touch panel 4 (step 101). At this time, it is difficult to determine whether the operator has touched the touch panel 4 intentionally or unintentionally. For this reason, it is assumed that the operator has intentionally touched it, and the electrostatic capacitance D of the electrode Sn or the electrode Sn that is the source of the wiring Tn arranged at the contact portion of the F touch panel 4 with the operator's finger F [N] is detected (step 102). Note that when the touch time between the touch panel 4 and the operator's finger F is extremely short and the change in the capacitance of the electrode Sn is less than a predetermined value set in advance, the operator's finger F is not touched. (“N” in step 102). Then, the finger value fv is calculated based on the algorithm described above (step 103). This finger value fv is compared with a preset reference value (step 104). This reference value is set in consideration of the size and number of the electrodes Sn, the thickness of the wiring Tn, the thickness of the touch panel 4 and the like. As described above, the finger value fv when the operator's finger F is touching the electrode Sn shows a large value, and the finger value fv when the operator's finger F is touching the wiring Tn shows a small value. Therefore, if the finger value fv exceeds the reference value (“Y” in step 104), it is determined that the operator has intentionally touched the finger F, and the operation is validated (step 105). However, if the finger value fv is less than or equal to the reference value (“N” in step 104), it is determined that the operator has unintentionally touched the finger F (ie, touched accidentally), and the operation is performed. Invalidate (step 106). Thereby, when an operator accidentally touches a part other than the switch (slider 13) of the touch panel 4, it is possible to reliably prevent the touch panel device 100 from malfunctioning. In particular, it is effective when the detection sensitivity of the touch panel device 100 is increased on the assumption that the operator wears gloves and operates.

  In the touch panel device 100 according to the present embodiment, the wiring Tn extending from each electrode Sn is alternately arranged in the region divided by the arrangement direction P of each electrode Sn, and the algorithm of the finger value fv is set. Just do it. Changing the arrangement of the wirings Tn requires only a slight change in the printing process of the electrode panel 4, so there is no risk of increasing the cost. The algorithm for calculating the finger value fv can be changed by a slight program change. Thereby, the touch panel device 100 of the present embodiment can be manufactured at low cost.

As shown in FIG. 8, a V-shaped slider 38 may be formed from the viewpoint of design, and a plurality of electrodes S _{1 to} S ₁₀ may be arranged so as to correspond to the slider 38.

Further, as shown in FIG. 9, a plurality of electrodes S _{1 to} S ₁₂ may be arranged so as to correspond to the rotary slider 14. In this case, even-numbered wirings T ₂ , T ₄ , T ₆ , T ₈ , T ₁₀ and T ₁₂ among the electrodes S _{1 to} S ₁₂ arranged side by side in the circumferential direction are more than the electrodes S _{1 to} S _12. The odd-numbered wirings T ₁ , T ₃ , T ₅ , T ₇ , T ₉ , and T ₁₁ extend outward and extend inward from the electrodes S _{1 to} S _12. The connection protrusions 33 and 34 can be extended through the through holes H.

The finger value fv when the operator's finger F touches the electrodes S _{1 to} S ₁₂ is increased by the same algorithm as in the first embodiment, and the finger when the operator touches the wirings T _{1 to} T ₁₂ is increased. The value fv becomes small. Thereby, the effectiveness of the operation can be determined by comparing the finger value fv with the reference value.

  Any number and shape of the electrodes Sn may be used. For example, like the electrode panel 39 shown in FIG. 10, the sliders 41 and 42 which have many electrodes Sn may be provided in two places.

  In the touch panel device 100 of each of the above-described embodiments, the driver's town can be disposed at a position where other occupants can touch-operate, for example, a front panel in the vehicle or a center console portion between the driver's seat and the passenger seat. .

  In the present specification, the case of the touch panel device 100 that operates the in-vehicle air conditioner has been described. However, the present invention can also be implemented for a touch panel device that operates a vehicle audio device.

  The present invention can be used as a touch panel device for a display in a car navigation device of a vehicle (for example, an automobile).

100 Touch Panel Device 4 Touch Panel 5, 39 Electrode Panel 8 Circuit Board (Detection Means)
13, 38, 41, 42 Slider (switch)
14 Rotary slider (switch)
19, Sn, S _{1 to} S ₁₂ electrode 26, Tn, T _{1 to} T ₁₂ wiring 35 Controller D Capacitance F Finger fv Finger value P Arrangement direction

Claims (6)

A touch panel on which switches that are operated by an operator touching a finger are displayed;
Provided in an overlapping state with the touch panel, a plurality of electrodes are arranged side by side so as to correspond to the switch, and the wiring extending from one of the adjacent electrodes is in the direction in which the electrodes are arranged An electrode panel arranged to extend in one area divided into two and the wiring extending from the other electrode is also arranged to extend in the other area ;
Detecting means for detecting the capacitance of each of the electrodes when the operator's finger touches the touch panel;
It is a value that changes according to each capacitance detected by the detection means, and becomes larger than a preset reference value when the operator's finger is touching the electrode placement portion of the touch panel, Calculating means for calculating a finger value, which is a value smaller than the reference value when a finger touches the wiring arrangement portion of the touch panel, using each capacitance detected by the detecting means;
A control unit that determines whether or not an operator's finger is touching a switch portion of the touch panel based on a comparison between the finger value calculated by the calculation unit and the reference value;
A capacitive touch panel device comprising: Capacitance D [n] (n is one end of an electrode arranged side by side) of an electrode or an electrode (hereinafter referred to as a “specific electrode”) arranged at a contact portion with the operator's finger in the touch panel The electrostatic capacity of the electrode adjacent to the specific electrode is set to D [n−1], D [n + 1], and the electrostatic capacity of the electrode adjacent to the specific electrode on the side opposite to the specific electrode side is set to When the electric capacities are D [n−2] and D [n + 2], and α and β are coefficients,
The calculation means uses the finger value fv as fv = (α × D [n] + D [n−1] + D [n + 1]) − (D [n−2] + D [n + 2] + β × D [others]). (However, the capacitance D [n] = 0 of the nonexistent electrode is calculated)
The control unit validates an operation in which the operator's finger touches the touch panel when the finger value fv is larger than a preset reference value, and invalidates the operation when the finger value fv is equal to or less than a reference value. The capacitive touch panel device according to claim 1, wherein: When there are a plurality of electrodes or wirings arranged at the contact portion between the operator's finger and the touch panel, the specific electrode having the maximum capacitance generated by contact with the finger is the specific electrode. The capacitive touch panel device according to claim 2 . 4. The capacitive touch panel device according to claim 2 , wherein the coefficients α and β are determined by a size of the electrode and / or a wiring pattern . 5. 5. The capacitive touch panel device according to claim 2, wherein the coefficient α is 2 and the coefficient β is 4. 6 . The capacitive touch panel device according to claim 1, wherein the capacitive touch panel device is mounted on a vehicle .