JP2013142907A - Input device and method for controlling input device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent any incorrect operation which is not intended by a user in a pressure-sensitive type input device.SOLUTION: An input device includes: a pressure-sensitive type touch panel; coordinate detection means for detecting the coordinates of a depressed part of the pressure-sensitive type touch panel; pressing force detection means for detecting the pressing force of the depressed part; and touch state determination means for, when the pressing force detected by the pressing force detection means exceeds a first threshold, determining that the pressure-sensitive type touch panel is touched, and for, when the pressing force detected by the pressing force detection means becomes lower than a second threshold which is smaller than the first threshold, determining that the pressure-sensitive type touch panel is not touched. The pressing force of the touch panel is detected, and when the pressing force exceeds the first threshold, the touch-off state is shifted to the touch-on state, and when the pressing force becomes lower than the second threshold which is smaller than the first threshold, the touch-on state is shifted to the touch-off state.

Description

  The present invention relates to an input device and a method for controlling the input device, and more particularly to a technique suitable for use in a digital camera including a pressure-sensitive touch panel.

  Conventionally, an input device has been proposed in which a touch panel sensor is added to a liquid crystal display to realize an operation switch function. The user inputs information to the apparatus by pressing a position corresponding to an icon such as a button displayed on the screen.

  In general, in a pressure sensitive touch panel such as a resistive film type, various proposals have been made from the viewpoint of preventing an erroneous operation unintended by a user and an erroneous detection of a pressed position. Patent Document 1 discloses an apparatus that ignores a non-touch state that occurs in a short time in order to eliminate chattering of a touch panel.

  Japanese Patent Application Laid-Open No. 2004-228561 discloses a device that includes a pressure-sensitive sensor that detects a pressing force on a touch panel, and stores a coordinate position only when the pressing force is within a predetermined allowable range, thereby reducing a detection error of the pressing position. ing. Patent Document 3 discloses an imaging apparatus that performs shooting preparation processing such as AF and AE in response to touchdown on a touch panel provided in the imaging apparatus, and performs shooting in response to subsequent touch-up.

JP 2006-106842 A JP 2009-269992 A JP 2011-193249 A

  However, in a pressure-sensitive touch panel, when the user presses the screen with a relatively weak force, an unstable state such as chattering continues for a long time, and if an attempt is made to remove chattering only by detecting the pressing of the time axis, Responsiveness will deteriorate.

  In the imaging apparatus proposed in Patent Document 3, the AF / AE operation is performed when the user presses the screen with a finger, and the imaging operation is performed when the user releases the finger from the screen. Therefore, a process that is performed when a transition is made (touch down) from a non-touched state (touch off state) to a touched state (touch on state), and a process that is performed when a transition is made from a touch on state to a touch off state (touch up). Different processes are assigned.

In such a case, when chattering occurs, it is determined that the user has moved from the touch-on state to the touch-off state even though the user has not lifted his / her finger from the screen, and the user does not intend to operate. was there.
In view of the above-described problems, an object of the present invention is to prevent an erroneous operation unintended by a user in a pressure-sensitive input device.

  An input device according to the present invention includes a pressure-sensitive touch panel, a coordinate detection unit that detects a coordinate of a pressed position of the pressure-sensitive touch panel, a pressure detection unit that detects a pressure of the pressed position, and the pressure detection unit. When the detected pressing force exceeds the first threshold value, it is determined that the touch is in a state, and the touch state determination unit is a second threshold value whose pressing force detected by the pressing force detection unit is smaller than the first threshold value. And touch state determination means for determining that the state is not touched below the touch point.

  ADVANTAGE OF THE INVENTION According to this invention, the erroneous operation which a user does not intend can be prevented in an input device.

It is a block diagram explaining the structure of the digital camera which shows 1st Embodiment. It is the schematic diagram of a touch panel, and the electrical equivalent circuit diagram in each operation | movement. It is a figure which shows an example of the time chart in case chattering generate | occur | produces. 5 is a flowchart for explaining an operation example of the digital camera of the first embodiment.

Hereinafter, a digital camera as an example of the first embodiment of the input device of the present invention will be described.
(First embodiment)
FIG. 1 is a block diagram illustrating a functional configuration of the digital camera according to the first embodiment.
In FIG. 1, reference numeral 10 denotes an imaging optical unit including a lens, a diaphragm, and the like, and performs focus adjustment and exposure adjustment. Reference numeral 11 denotes an image sensor such as a CCD that converts an optical image into an electrical signal.

  Reference numeral 12 denotes an A / D conversion circuit that converts an analog image signal output from the image sensor into digital image data. Reference numeral 13 denotes gamma processing, interpolation processing, matrix conversion, and the like on the image data output from the A / D conversion circuit 12. And a signal processing unit that creates video data. 14 is a system bus for writing / reading video data and various control data to / from a memory (DRAM) 15, 16 is a CPU that controls various controls, and 17 is a recording unit that records captured images on a recording medium such as an SD card. It is. A display unit 18 displays image data on an LCD monitor or the like.

  Reference numeral 19 denotes a pressure-sensitive touch panel such as a resistive film type, which is disposed on the upper surface of the display unit 18. A touch panel control unit 20 measures the pressed coordinates and the pressing force of the touch panel 19 and notifies the CPU 16 of the measured coordinates.

Operations of the touch panel 19 and the touch panel control unit 20 will be described with reference to FIG.
FIG. 2A is a schematic diagram showing the structure of the touch panel 19.
An upper electrode 101 and a lower electrode 102 made of a transparent resistance film such as an ITO (Indium Tin Oxide) film are arranged to face each other. A non-contact state is maintained between the upper electrode 101 and the lower electrode 102 by a spacer (not shown). Electrodes X + and X− are attached to both ends of the upper electrode 101 in the X direction, and electrodes Y + and Y− are attached to both ends of the lower electrode 102 in the Y direction.
The touch panel control unit 20 has a function of applying a voltage to each of the electrodes described above and reading out the potential of each electrode by A / D conversion.

FIGS. 2B to 2F show an electrical equivalent circuit in each operation of the touch panel 19 and the touch panel control unit 20.
FIG. 2B is an electrical equivalent circuit when pressing is detected, and a voltage is applied between the electrode X + and the electrode Y− via a pull-up resistor (PU). When the touch panel 19 is pressed and the contact resistance value Rt between the upper electrode 101 and the lower electrode 102 becomes a value sufficiently smaller than the pull-up resistance, the electrode X + changes from High to Low.

  When the electrode X + becomes Low, the touch panel control unit 20 generates an interrupt to the CPU 16 to notify that the touch panel 19 is pressed. Here, since the pressing force and the contact resistance value Rt are in an inversely proportional relationship, in this embodiment, it is assumed that a pressing detection interrupt occurs when the pressing force is pressed at a second threshold value z2 or higher.

  FIG. 2C is an electrical equivalent circuit when detecting the X coordinate, and a voltage is applied between the electrode X + and the electrode X−. A value obtained by A / D converting the potential of the electrode Y + is proportional to the voltage dividing resistor Rx of the upper electrode 101, and the X coordinate of the pressed position can be detected from the obtained voltage dividing resistor Rx.

  FIG. 2D is an electrical equivalent circuit when detecting the Y coordinate, and a voltage is applied between the electrode Y + and the electrode Y−. The value obtained by A / D converting the potential of the electrode X + is proportional to the voltage dividing resistance Ry of the lower electrode 102, and the Y coordinate of the pressed position can be detected from the obtained voltage dividing resistance Ry.

FIGS. 2E and 2F are electrical equivalent circuits at the time of detecting the pressing force, and a voltage is applied between the electrode Y + and the electrode X−. A value measured by A / D converting the potential of the electrode X + is Z1, and a value measured by A / D converting the potential of the electrode Y + is Z2. Then, the contact resistance value Rt between the upper electrode 101 and the lower electrode 102 is also calculated using the voltage dividing resistance Rx of the upper electrode 101 described above.
Rt = Rx × (Z2 / Z1-1)
As required.
Here, since the pressing force and the contact resistance value Rt are in an inversely proportional relationship, in this embodiment, it is assumed that the pressing force is small when the contact resistance value Rt is large, and the pressing force is large when the contact resistance value Rt is small. To do.

  In the present embodiment, the touch-off state transitions from the touch-off state when the pressing force is pressed at the first threshold value z1 or more, and the touch-on state changes from the touch-on state to the touch-off state when the pressing force is pressed below the second threshold value z2. It is characterized by a transition. However, z1> z2. That is, when the contact resistance value Rt is less than or equal to the threshold value, the touch-off state transitions to the touch-on state, and when the above-described pressing detection interruption is lost, the touch-on state transitions to the touch-off state.

FIG. 3 shows an example of a time chart when chattering occurs when the user pushes down the touch panel 19 with a relatively weak pressing force.
At time t0, the user starts to press the touch panel 19.
At time t1, the pressing force becomes equal to or greater than the second threshold z2, and a pressing detection interrupt occurs.
From time t1 to t2, a pressing detection interruption occurs, but since the pressing force is less than the first threshold value z1, the touch-off state remains unchanged.

From time t2 to t3, chattering occurs, the pressing force falls below the second threshold value z2, and no pressing detection interruption occurs.
From time t3 to t4, the pressing force again becomes equal to or higher than the second threshold value z2, and the pressing detection interruption occurs. However, since the pressing force is less than the first threshold value z1, the touch-off state remains unchanged.

At time t4, the pressing force becomes equal to or higher than the first threshold value z1, and the touch-on state is entered.
From time t5 to t6, chattering occurs and the pressing force becomes less than the first threshold value z1, but the touch-on state remains unchanged.
At time t7, the pressing force becomes less than the second threshold z2, there is no interruption of pressing detection, and the touch-on state is changed to the touch-off state.

The operation of the digital camera according to the first embodiment will be described using the flowchart of FIG. The processing in the flowchart of FIG. 4 is realized by the CPU 16 executing a program recorded in a non-volatile memory (ROM) (not shown) by expanding the memory 15 functioning as a work memory.
In S401, when the user presses the touch panel 19 with a pressing force equal to or greater than the second threshold value z2, a touch detection interrupt is generated from the touch panel control unit 20 to the CPU 16, and the process proceeds to S402.
In S <b> 402, when an interruption of pressing detection occurs, the CPU 16 measures the contact resistance value Rt from the touch panel control unit 20 by the method described above.

  In S403, a touch state determination process is performed to determine whether or not the contact resistance value Rt is equal to or less than a threshold value. As a result of this determination, if it is determined that the contact resistance value Rt is equal to or less than the threshold value, that is, if the pressing force is determined to be equal to or greater than the first threshold value z1, the process proceeds to S404. On the other hand, when it is determined that the contact resistance value Rt is greater than the threshold value, that is, the pressing force is less than the first threshold value z1, the process returns to S401.

In S404, the CPU 16 measures the X coordinate and the Y coordinate of the pressed position from the touch panel control unit 20 by the method described above.
In S405, the CPU 16 determines that the touch panel 19 has transitioned from the touch-off state to the touch-on state, and executes the first process. Here, as the first processing, for example, the pressed position on the screen is set as the AF / AE area, and the imaging optical unit 10 is controlled to perform the AF / AE operation.

  In S406, the X coordinate and the Y coordinate are measured. Next, in S407, a touch state determination process is performed to determine whether or not the pressing force is equal to or greater than the second threshold value z2. If the result of this determination is that it is greater than or equal to the second threshold z2, the process returns to S406. As a result, in S406 and S407, the CPU 16 continues to measure the X coordinate and the Y coordinate of the pressed position until there is no interruption of the pressing detection.

If it is determined in S407 that the pressing force is less than the second threshold value z2, no pressing detection interruption occurs, and the process proceeds to S408.
In S408, the CPU 16 determines that the touch panel 19 has transitioned from the touch-on state to the touch-off state, and executes a second process. Here, as the second processing, for example, a photographing operation is performed, and the photographed image is recorded on a recording medium such as an SD card by the recording unit 17.

(Second Embodiment)
Hereinafter, a digital camera as an example of the second embodiment of the input apparatus of the present invention will be described.
In the first embodiment described above, the first threshold value z1 is set as the threshold value of the pressing force from the touch-off state to the touch-on state. When the first threshold value z1 is increased, an erroneous operation unintended by the user can be prevented. However, on the other hand, the user needs to press the touch panel with a stronger pressing force, and the reaction becomes dull.

  A digital camera has a plurality of operation modes, for example, a recording mode (photographing mode) and a playback mode. Since the shooting operation is performed in the recording mode, it is necessary to prevent the erroneous operation unintended by the user as much as possible.In the playback mode, the purpose is to view the recorded image. It must be nimble.

  Therefore, the present embodiment is characterized in that the value of the first threshold value z1 of the pressing force described above is changed to a value lower than that in the recording mode in the reproduction mode. As a result, erroneous operations can be reliably prevented in the recording mode, and a light reaction can be realized in the reproduction mode.

  Further, in the above-described embodiment, the case where the present invention is applied to a digital camera has been described as an example. However, this is not limited to this example, and any electronic device capable of touch input using a touch panel is applicable. It is.

  That is, the present invention can be applied to a personal computer or PDA having a touch panel, a mobile phone terminal, a portable image viewer, a printer device including a display, a digital photo frame, a music player, a game machine, an electronic book reader, and the like.

(Other embodiments)
The present invention can also be realized by executing the following processing. That is, software (computer program) that implements the functions of the above-described embodiments is supplied to a system or apparatus via a network or various computer-readable storage media. Then, the computer (or CPU, MPU, etc.) of the system or apparatus reads out and executes the program.

DESCRIPTION OF SYMBOLS 10 Imaging optical part, 11 Image pick-up element, 12 A / D conversion circuit, 13 Signal processing part, 14 System bus, 15 Memory (DRAM), 16 CPU, 17 Recording part, 18 Display part, 19 Touch panel, 20 Touch panel control part

Claims (8)

A pressure-sensitive touch panel,
Coordinate detection means for detecting the coordinates of the pressed position of the pressure-sensitive touch panel;
A pressing force detecting means for detecting a pressing force at the pressed position;
When the pressing force detected by the pressing force detection means exceeds a first threshold value, it is determined that the touch is being performed, and the pressing force detected by the pressing force detection means is a second threshold value that is smaller than the first threshold value. An input device, comprising: a touch state determination unit that determines that a touch is not made when the value is below.   Control means for performing control so that the first process is executed when it is determined that the touch state determination means is touching, and the second process is executed when it is determined that the touch state is not touched. The input device according to claim 1. The input device has a plurality of operation modes,
The input device according to claim 1, wherein the first threshold value is changed according to an operation mode.   The input device according to claim 1, wherein the input device is used in an image pickup device including an image pickup unit.   The first threshold value used when the operation mode is a playback mode is used in an imaging apparatus including an imaging unit, and is smaller than the first threshold value when the operation mode is a shooting mode. The input device according to claim 3. A control method for an input device, comprising: a pressure-sensitive touch panel; coordinate detection means for detecting coordinates of a pressed position of the pressure-sensitive touch panel; and pressing force detection means for detecting a pressing force of the pressed position,
When the pressing force detected by the pressing force detection means exceeds a first threshold value, it is determined that the touch is being performed, and the pressing force detected by the pressing force detection means is a second threshold value that is smaller than the first threshold value. A control method for an input device, comprising: a touch state determination step for determining that the touch is not performed when the value is less than. An input device control method using an input device having a pressure-sensitive touch panel, a coordinate detection unit that detects a coordinate of a pressing position of the pressure-sensitive touch panel, and a pressing force detection unit that detects a pressing force of the pressing position is used in a computer. A program to be executed,
When the pressing force detected by the pressing force detection means exceeds a first threshold value, it is determined that the touch is being performed, and the pressing force detected by the pressing force detection means is a second threshold value that is smaller than the first threshold value. A program that causes a computer to execute a touch state determination step that determines that a touch is not made when the value is below.   A computer-readable storage medium storing the program according to claim 7.

Images