Touch Panel

Abstract

To provide a touch panel for enabling a user to intuitively grasp a state of a touch pad.SOLUTION: A touch panel 100 includes a touch pad 10, a display unit 20 and a control unit 30. The touch pad 10 is a capacitance type having light transmissivity. The display unit 20 is provided at the back of the touch panel 10 to luminously display an image. The control unit 30 detects a capacitance of the touch pad 10, and specifies that the touch pad 10 is in a water-covered state different from a normal state in the case where the detected capacitance is included within a specific range. The control unit 30 can make the display unit 20 emit light with luminance lower than that in the normal state, the luminance corresponding to a value of the detected capacitance in the case where the touch pad 10 is in the water-covered state.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a touch panel. [Background technology]

[0002] As a conventional touch panel, for example, Patent Document 1 describes a touch panel that includes a capacitive touch pad on which a user performs touch input, and a display unit that displays an image and is provided behind the touch pad. The touch panel described in Patent Document 1 performs calibration regardless of whether or not there is contact with a finger or the like. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-87079 A Summary of the Invention [Problem to be solved by the invention]

[0004] Even if calibration is performed, the detection accuracy of the touch input on the touchpad fluctuates if the touchpad is covered in rainwater, muddy water, etc. If a user performs a touch input in a state where the detection accuracy of the touchpad has decreased, the input may not be reflected, which may be annoying to the user.

[0005] The present disclosure has been made in consideration of the above-described circumstances, and has an object to provide a touch panel that allows a user to intuitively grasp the state of the touchpad. [Means for solving the problem]

[0006] In order to achieve the above object, the touch panel according to the present disclosure comprises: a translucent capacitive touch pad; A display unit provided behind the touch pad for displaying an image by emitting light; a control unit that detects a capacitance of the touch pad, and determines that the touch pad is in a water-damaged state different from a normal state when the detected capacitance is within a specific range; When the touchpad is in the wet state, the control unit is capable of causing the display unit to emit light at a lower brightness than when the touchpad is in the normal state, and at a brightness that corresponds to the detected capacitance value. Effect of the Invention

[0007] According to the present disclosure, it is possible for a user to intuitively grasp the state of the touchpad. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram showing a configuration of a touch panel according to an embodiment of the present disclosure. [Diagram 2] FIG. 2 is a schematic plan view of the touch sensor according to the embodiment. [Diagram 3] FIG. 4 is a diagram for explaining a specific range and an input threshold value according to the embodiment. [Figure 4] 6 is a flowchart showing an example of a pad state notification process according to the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] An embodiment of the present disclosure will be described with reference to the drawings.

[0010] 1, a touch panel 100 according to an embodiment of the present invention includes a translucent capacitive touch pad 10, a display unit 20 that displays an image by emitting light, and a control unit 30 that controls the operation of the touch pad 10 and the display unit 20. The touch panel 100 enables a user to operate a specific device based on a touch input made on the touch pad 10 by a user's hand.

[0011] In this embodiment, the display unit 20 and the device 200 are objects that can be operated by touch input. The device 200 is, for example, a device mounted on a construction machine such as a hydraulic excavator. A user of the touch panel 100 is, for example, a driver / operator of the construction machine. The touch panel 100 is, for example, detachably provided near the driver's seat of the construction machine.

[0012] The touch pad 10 has a rectangular panel shape in a plan view. The touch pad 10 includes a cover 11 and a touch sensor 12.

[0013] The cover 11 is a plate-like member made of a translucent resin such as polymethylmethacrylate (PMMA). The front surface of the cover 11 serves as an input surface that is contacted by the hand of a user who performs touch input. Touch input refers to an action of the user touching the input surface of the touchpad 10 with their hand. Note that touch input is not limited to bare hands, and may be an input action using a gloved hand or the like. The touch sensor 12 is a sheet-like capacitance-type touch sensor, and is provided on the back surface of the cover 11.

[0014] 2, the touch sensor 12 has a plurality of driving electrodes 12a and a plurality of detection electrodes 12b. The driving electrodes 12a are strip-shaped extending in the X direction and are arranged at intervals in the Y direction. The detection electrodes 12b are strip-shaped extending in the Y direction and are arranged at intervals in the X direction. The driving electrodes 12a and the detection electrodes 12b are made of, for example, ITO (Indium Tin Oxide), are insulated from each other, and are arranged crossing each other.

[0015] The display unit 20 is composed of an LCD (Liquid Crystal Display), an OLED (Organic Light Emitting Diodes), or the like, and is provided behind the translucent touchpad 10, as shown in Fig. 1. The display unit 20 emits and displays an image on the display surface 20a under the control of the control unit 30. The image displayed on the display surface 20a is visible to the user through the touchpad 10.

[0016] The control unit 30 is composed of a microcomputer and includes, for example, a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), a sensor driver that drives the touch sensor 12, and a display driver that drives the display unit 20. The ROM of the control unit 30 stores programs for controlling the operations of the touch sensor 12 and the display unit 20, including a program for executing a pad state notification process described below. Note that the control unit 30 is not limited to an example composed of one computer, and may be realized by multiple computers working together.

[0017] As shown in FIG. 1, the control unit 30 includes, as main functional units, a capacitance analysis unit 31, a touch input detection unit 32, and a display control unit 33.

[0018] The capacitance analysis unit 31 detects the capacitance of the touch pad 10 and analyzes the distribution and change of the detected capacitance. For example, the capacitance analysis unit 31 sequentially supplies a drive signal to the multiple drive electrodes 12a of the touch sensor 12, sequentially selects the multiple detection electrodes 12b, and acquires the capacitance at the intersection between the drive electrode 12a to which the drive signal is supplied and the selected detection electrode 12b. Then, the capacitance analysis unit 31 generates a distribution of the capacitance at the coordinates (X, Y) set in the touch sensor 12, which are defined as the intersection of the drive electrode 12a and the detection electrode 12b.

[0019] When the capacitance at one or more points on the touchpad 10 is included in a specific range R shown in FIG. 3, the capacitance analysis unit 31 determines that the touchpad 10 is in a wet state different from the normal state. The normal state is a state in which the touchpad 10 is assumed to be able to detect touch input. On the other hand, the wet state is a state in which rainwater, muddy water, or the like is attached to the input surface of the touchpad 10. As an example, when the capacitance of the touchpad 10 is -10 to 10 when no object that generates capacitance is touching the touchpad 10, the specific range R is a range of 100 to 200 (100≦R≦200). The capacitance acquired by the capacitance analysis unit 31 (i.e., the control unit 30) is in an arbitrary unit (au) that is arbitrarily determined according to the design.

[0020] Specifically, the water exposure state includes a first water exposure state and a second water exposure state in which the touchpad 10 is more wet than the first water exposure state. When the number of points on the touchpad 10 where the capacitance is in the specific range R is greater than a set number, the capacitance analysis unit 31 determines that the touchpad 10 is in the second water exposure state. On the other hand, when the number of points on the touchpad where the capacitance is in the specific range R is equal to or less than the set number, the capacitance analysis unit 31 determines that the touchpad 10 is in the first water exposure state. The set number is stored in ROM in advance and can be set to any number, for example, "2". Note that the set number may be the same as or different from the effective touch number described below.

[0021] Here, the location of the touchpad 10 refers to a location where capacitance is detected on the input surface of the touchpad 10. The location may correspond one-to-one to the coordinates (X, Y) set on the touch sensor 12, or one location may correspond to a set of multiple coordinates (X, Y). When one location corresponds to multiple coordinates (X, Y), the determination of whether the capacitance detected at the one location is included in the specific range R is arbitrary depending on the design. For example, when the capacitance detected at any number or more of the multiple coordinates (X, Y) corresponding to one location is included in the specific range R, or when the average value of the capacitance detected at each of the multiple coordinates (X, Y) corresponding to one location is included in the specific range R, the capacitance analysis unit 31 may determine that the capacitance detected at the one location is included in the specific range R.

[0022] When the capacitance is within the specific range R and the number of locations where water droplets such as rainwater or muddy water are assumed to be attached is greater than a set number, the capacitance analysis unit 31 identifies the state as a second water-damaged state, which indicates a greater degree of water damage. In the second water-damaged state, it is difficult to properly detect touch input, so the capacitance analysis unit 31 does not accept touch input. In other words, it invalidates the operation corresponding to the input. Specifically, when the capacitance analysis unit 31 identifies the state as the second water-damaged state, it sets an input invalid flag stored in a flag storage area of ​​the RAM to an on state, thereby executing control not to accept touch input until the second water-damaged state is resolved, as described below.

[0023] If there is a location on the touchpad 10 where the capacitance is equal to or greater than the input threshold T based on the capacitance distribution generated by the capacitance analysis unit 31, the touch input detection unit 32 creates a motion trajectory of the user's hand based on the coordinate information of that location. The input threshold T is set in advance in the ROM as a value exceeding a specific range R, as shown in FIG. 3, and is, for example, "300". Then, the touch input detection unit 32 compares the created motion trajectory with the trajectory pattern stored in the ROM to detect a touch input. In this embodiment, the touch input is detected by a mutual capacitance method.

[0024] The gestures by touch input that can be detected by the touch input detection unit 32 may be known actions such as tapping, swiping, scrolling, pinching in, pinching out, etc. Any method for detecting the gesture may be used, and known methods such as a pattern matching method, a Nearest Neighbor algorithm (NN method), a k-Nearest Neighbor algorithm (k-NN method), etc. may be used.

[0025] In this embodiment, the valid touch number, which indicates the number of touches that the touch input detection unit 32 can detect simultaneously, is set to "2" as an example. In other words, if it is determined that an object such as a user's finger is in contact with the touchpad 10 at more than two points (two locations), the touch input detection unit 32 does not detect a touch input. On the other hand, if a touch is detected that is within the valid touch number, that is, one or two points, the touch input detection unit 32 detects the touch input as described above. The valid touch number is stored in ROM in advance, and is not limited to the exemplified "2", and can be set to any number.

[0026] When the touch input detection unit 32 detects a touch input, it outputs an operation command corresponding to the content of the touch input to the target device. Data indicating the content of the operation command corresponding to the touch input is stored in the ROM in advance. This makes it possible to execute an operation of the target device according to the touch input.

[0027] In this embodiment, the display unit 20 and the device 200 are objects that can be operated under the control of the touch input detection unit 32. For example, the device 200 is a device implemented in a construction machine as described above, and includes an ECU (Electronic Control Unit) that controls the operation of each part of the construction machine, and various systems configured within the construction machine. The touch input detection unit 32 is capable of transmitting operation commands to the device 200 not only by wired communication but also by wireless communication. Therefore, even if the user is located away from the construction machine, the user can use the touch panel 100 to perform a predetermined operation on the device 200. The device 200 performs an operation according to the operation command from the touch input detection unit 32.

[0028] The display control unit 33 controls the display operation including the control of the emission brightness of the display unit 20. In particular, when the touch pad 10 is in the first water-exposed state, the display control unit 33 of this embodiment causes the display unit 20 to emit light at a brightness lower than that in the normal state and corresponding to the value of the capacitance detected by the capacitance analysis unit 31. Specifically, assuming that the brightness of the display unit 20 in the normal state (hereinafter referred to as normal brightness) is L0 and the value of the capacitance detected in the first water-exposed state (i.e., a value within the specific range R) is C, the display control unit 33 adjusts the brightness L1 of the display unit 20 in the first water-exposed state using the formula L1=(1-C / T)×L0. T is the input threshold value mentioned above. For example, when C=100 and T=300, L1=2 / 3×L0, so the display control unit 33 causes the display unit 20 to emit light at a brightness L1 that is 2 / 3 times the brightness L0, which is lower than the normal brightness L0.

[0029] When the touchpad 10 is in the first wet state, the display control unit 33 may cause the display unit 20 to emit light with a luminance that changes stepwise according to the detected capacitance value C. Specifically, the specific range R may be divided in advance into finer ranges ΔR1, ΔR2, ... ΔRn (n is a natural number), and when the capacitance value C detected in the first wet state is included in the range ΔRn, the display control unit 33 may adjust the luminance L1 of the display unit 20 in the first wet state using the formula L1 = {1 - (any value included in ΔRn) / T} × L0. For example, when the specific range R is 100 ≦ R ≦ 200, the specific range R is divided in advance into a range ΔR1 of 100 to 125, a range ΔR2 of 125 to 150, a range ΔR3 of 150 to 175, and a range ΔR4 of 175 to 200. Then, if the capacitance value C detected in the first water exposure state is included in the range of ΔR1 and an arbitrary number included in ΔR1 is set to 100, the display control unit 33 adjusts the luminance L1 of the display unit 20 in the first water exposure state using the formula L1={1-100 / T)}×L0. In this way, by making the display unit 20 emit light with a luminance that changes stepwise according to the capacitance value C, it is possible to prevent the luminance of the display unit 20 from changing frequently in response to minute changes in the capacitance value C.

[0030] Furthermore, in the case of the second water damage state, the display control unit 33 turns off the display unit 20. This allows the user to intuitively understand that touch input cannot be performed normally at present. The turning-off mode of the display unit 20 does not only simply black out the entire display screen, but also includes a mode in which a message image such as "Input is currently not possible" or "Please wipe off any water or dirt from the surface of the device" is displayed in a covert manner on a blackout screen that is displayed widely across the display screen of the display unit 20. In other words, turning off the display unit 20 includes not only turning off the entire display screen, but also turning off a part of it.

[0031] Furthermore, the display control unit 33 causes the display unit 20 to display a target image (not shown) showing information related to an operable target device. The information shown by the target image includes not only information showing the target device itself, but also information showing operation items of the target device and some functions of the target device. The target image may be configured to show information related to the target device using characters, figures, icons, etc. This concludes the explanation of the configuration of the touch panel 100.

[0032] Next, a pad state notification process that is executed by the control unit 30 and notifies the user of the state of the touch pad 10 by the emission brightness of the display unit 20 will be described with reference to FIG.

[0033] (Pad status notification process) 4, the control unit 30 first determines whether or not the detected capacitance is below a specific range R (step S1). At the start of the pad state notification process, the control unit 30 causes the display unit 20 to emit light at normal luminance L0, and the input invalid flag is in the OFF state.

[0034] If the detected capacitance is below the specific range R (step S1; Yes), the control unit 30 causes the display unit 20 to emit light at normal luminance L0 and sets the input invalid flag to the OFF state (step S2). In other words, when step S2 is executed, the touchpad 10 is in a normal state, i.e., not wet. After executing step S2, the control unit 30 returns to step S1 and executes the process.

[0035] If the detected capacitance is not below the specific range R (step S1; No), the control unit 30 determines whether the detected capacitance is within the specific range R (step S3).

[0036] If the capacitance is not within the specific range R (step S3; No), the control unit 30 determines whether the input invalid flag is off or not (step S4). If the input invalid flag is on (step S4; No), the control unit 30 returns to step S1 and executes the process. In other words, if the input invalid flag is on, touch input is not accepted. The input invalid flag is set to the on state when the touchpad 10 is identified as being in a second water-damaged state (step S10), as described below.

[0037] If the input invalid flag is in the OFF state in step S4 (step S4; Yes), the control unit 30 determines whether or not a touch input has been detected using the function of the touch input detection unit 32 described above (step S5). If a touch input has not been detected (step S5; No), the control unit 30 returns to step S1 and executes the process. Here, if the answer is No in step S3, this is the case when the detected capacitance exceeds the specific range R. Therefore, if a touch input cannot be detected in step S5, this is the case when the control unit 30 has detected a number of touches exceeding the valid number of touches, or when a gesture by a touch input cannot be identified.

[0038] On the other hand, if a touch input is detected (step S5; Yes), the control unit 30 outputs an operation command corresponding to the content of the touch input to the target device (step S6), and then returns to step S1 to execute the process.

[0039] In step S3, if the capacitance is within the specific range R (step S3; Yes), this corresponds to the touchpad 10 being in a wet state. In this case, the control unit 30 determines whether the number of points where the capacitance is detected is within a set number previously stored in the ROM, in order to determine whether the touchpad 10 is in the first wet state or the second wet state (step S7).

[0040] If the number of locations where capacitance is detected is within the set number (step S7; Yes), the control unit 30 determines that the touchpad 10 is in the first water exposure state, and causes the display unit 20 to emit light at a luminance L1 lower than the normal luminance L0, as described above, using the function of the display control unit 33 (step S8). As described above, the luminance L1 increases or decreases depending on the magnitude of the detected capacitance value, so that the user can intuitively grasp the degree of water exposure from the state of illumination of the display unit 20.

[0041] Following step S8, the control unit 30 turns off the input invalid flag (step S9), and returns to step S1 to execute the process. In this embodiment, the input invalid flag is not turned on in the first water-damaged state. Therefore, when the process transitions to steps S3, S4, S5, and S6 after the process of step S9, even if the degree of light emission of the display unit 20 indicates the first water-damaged state, touch input and operation of the target device according to the input are possible.

[0042] On the other hand, if the number of locations where capacitance is detected exceeds the set number in step S7 (step S7; No), the control unit 30 determines that the touchpad 10 is in the second water-damaged state, and uses the function of the display control unit 33 to turn off the display unit 20 (step S10) and set the input invalid flag to the ON state (step S11), as described above. This allows the user to intuitively understand that touch input is currently not possible. After processing step S11, the control unit 30 returns to step S1 and executes the process.

[0043] After the process of step S11, the control unit 30 does not accept touch input until the process transitions to steps S1 and S2 and the touchpad 10 changes from the second wet state to the normal state, or until the process transitions to steps S1, S3, S7, S8, and S9 and the touchpad 10 changes from the second wet state to the first wet state. In other words, the control unit 30 does not accept touch input until the second wet state is resolved. The above touch state notification process is executed continuously, for example, while the touch panel 100 is activated.

[0044] The above-described touch panel 100 provides the following advantages.

[0045] (1) When the detected capacitance falls within a specific range R, the control unit 30 of the touch panel 100 determines that the touchpad 10 is in a wet state that is different from the normal state, and when the touchpad 10 is in a wet state, it is capable of causing the display unit 20 to emit light at a brightness L1 that is lower than the brightness in the normal state (normal brightness L0) and that corresponds to the value of the detected capacitance. The luminance L1 increases or decreases according to the magnitude of the detected capacitance value, allowing the user to intuitively grasp the degree of water exposure from the state of light emission of the display unit 20. In other words, the touch panel 100 having the above configuration (1) allows the user to intuitively grasp the state of the touch pad 10.

[0046] (2) When the touch pad 10 is wet, the control unit 30 may be capable of causing the display unit 20 to emit light with a brightness that changes in stages according to the value of the detected capacitance. According to the above configuration (2), it is possible to prevent the luminance of the display unit 20 from frequently changing in response to minute changes in the capacitance value.

[0047] (3) Specifically, the water exposure state includes a first water exposure state and a second water exposure state in which the touchpad 10 is more wet than the first water exposure state. If the number of points where the capacitance detected by the touchpad 10 is within specific range R is greater than a set number, the control unit 30 determines that the touchpad 10 is in the second water exposure state and turns off the display unit 20, and if the number of points where the capacitance detected by the touchpad 10 is within specific range R is equal to or less than the set number, the control unit 30 determines that the touchpad 10 is in the first water exposure state and causes the display unit to emit light at a brightness L1 according to the value of the detected capacitance. According to the above configuration (3), the user can intuitively know that the touchpad 10 is in the second water exposure state by the display unit 20 being turned off (the entire screen or a part of the screen being turned off).

[0048] (4) The control unit 30 detects a touch input made to the touchpad 10 based on the detected capacitance, and is capable of accepting the touch input when the touchpad 10 is in a normal state or a first wet state, and does not accept the touch input when the touchpad 10 is in a second wet state. According to the above configuration (4), touch input is not accepted until the second water damage state, in which it is difficult to detect the touch input or there is a high possibility of erroneous detection, is resolved, thereby making it possible to suppress erroneous operations.

[0049] The present disclosure is not limited to the above-described embodiments and drawings. Modifications (including the deletion of components) can be made as appropriate within the scope of the present disclosure.

[0050] The specific range R, input threshold T, setting number, and valid touch number shown above are merely examples, and can be set or changed arbitrarily according to design.

[0051] The shape and configuration of the touch panel formed by the touch pad 10 and the display unit 20 are arbitrary, and any known shape and configuration can be appropriately adopted.

[0052] In the above embodiment, the touch panel 100 is used in a construction machine, but the purpose and the target user are not limited and may be any purpose. However, the touch panel 100 is suitable for use outdoors.

[0053] In the above, an example has been described in which touch input is performed by the user's hand. Although the hand is assumed to be the fingers or palm, it may be the part of the human body from the shoulder forward. Furthermore, as long as touch input can be performed safely, touch input may be performed by a part other than the user's hand.

[0054] In the above description, descriptions of well-known technical matters have been omitted as appropriate in order to facilitate understanding of the present disclosure. [Explanation of symbols]

[0055] 100...Touch panel 10...touch pad, 11...cover, 12...touch sensor 20...display section, 20a...display surface 30: control unit, 31: capacitance analysis unit, 32: touch input detection unit, 33: display control unit R: specific range, T: input threshold 200…Equipment

Claims

1. a light-transmitting capacitive touch pad; A display unit provided behind the touch pad for displaying an image by emitting light; a control unit that detects a capacitance of the touch pad, and determines that the touch pad is in a water-damaged state different from a normal state when the detected capacitance is within a specific range; When the touch pad is in the water-damaged state, the control unit is capable of causing the display unit to emit light at a lower brightness than when the touch pad is in the normal state and at a brightness corresponding to the detected capacitance value. Touch panel.

2. When the touch pad is in the water-exposed state, the control unit is capable of causing the display unit to emit light with a luminance that changes stepwise according to the detected capacitance value. The touch panel according to claim 1 .

3. the water exposure state includes a first water exposure state and a second water exposure state in which the touch pad is more heavily exposed to water than the first water exposure state; The control unit is When the number of points where the capacitance detected by the touch pad is within the specific range is greater than a set number, the touch pad is determined to be in the second water-exposed state and the display unit is turned off. When the number of points where the capacitance detected on the touchpad is within the specific range is equal to or less than the set number, the touchpad is identified as being in the first water-exposed state, and the display unit is caused to emit light at a luminance corresponding to the value of the detected capacitance. The touch panel according to claim 1 or 2.

4. The control unit is Detecting a touch input on the touchpad based on the detected capacitance; the touch pad is capable of receiving the touch input when the touch pad is in the normal state or the first wet state; When the touch pad is in the second wet state, the touch input is not accepted. The touch panel according to claim 3 .

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