Patent Publication Number: US-8970528-B2

Title: Information input device, information input method, and program

Description:
TECHNICAL FIELD 
     The present invention relates to, for example, an information input device that operates a graphical user interface (GUI) screen of an electronic device, and in particular to, for example, an information input device including a clickable touch sensor that operates the GUI screen with a touch sensor. 
     BACKGROUND ART 
     In electronic devices including displays, such as PCs and mobile phones, touch sensors, for example, touch pads are well known as one type of input devices that operate GUI screens displayed on the displays. In an information input device including a touch sensor, the user traces the touch sensor with a finger to enable moving of a cursor on the GUI screen, thus resulting in an intuitive GUI operation according to movement of the user&#39;s finger. 
     In addition to a location input operation of moving a cursor on a screen, the general GUI operations need an operation of determining an object such as an icon and a button on the screen, for example, an operation represented by a left click of a mouse. 
     The information input devices including the conventional touch sensors perform such an operation of determining an object by pressing a button placed near the touch sensor once or twice or by lightly tapping the surface of the touch sensor once or twice. 
     For example, any icon on a screen is selected and determined (executed) by (i) tracing the surface of the touch sensor with a finger to move a cursor on the screen to a target icon, (ii) once moving the finger away from the touch sensor, and (iii) pressing a button placed near the touch sensor twice or by lightly tapping the surface of the touch sensor twice. 
     In this case, since the user needs to move the finger away from the touch sensor at least once, there is a problem that the user cannot continuously and naturally move the finger. 
     Here, a clickable touch sensor is known as one of the solutions for improving the operability of a general touch sensor. The touch sensor is movable upward and downward, and includes a mechanical switch immediately underneath the touch sensor (See PTL 1). 
     The clickable touch sensor can select and determine an object on the GUI screen by pressing the touch sensor to press down the switch immediately underneath the touch sensor. For example, the user can select and determine (execute) any icon on the GUI screen by tracing the surface of the touch sensor, moving a cursor on the screen to the target icon, and pressing down the touch sensor. 
     In other words, such an information input device including a clickable touch sensor can continuously and naturally perform an operation without moving the finger away from the touch sensor, thus improving the operability of the user more than the conventional touch sensors. 
     While the operability has been improved, there are cases where, when the user presses a switch below a clickable touch sensor with the finger, the finger horizontally moves with the pressure and the position of the cursor is displaced (hereinafter referred to as “misclick”). 
     In particular, when the size of objects on the screen is small and a space between the adjacent objects is narrow, in the case where the position of the cursor is slightly displaced, an object near the target object is selected and determined, and erroneous operations frequently occur. 
     In order to solve the problem of the misclick on the clickable touch sensor, PTL 2 suggests a method for preventing the misclick, using an information input device including a touch sensor having variable flexibility with the pressure of a finger operation of the user. 
       FIG. 18  illustrates an information input system using a clickable touch sensor having the conventional misclick prevention function described in PTL 2. 
     As illustrated in  FIG. 18 , the information input system includes a clickable touch sensor  100 , a touch information detecting unit  103 , a screen display device  500 , a cursor position calculating unit  106 , a cursor display control unit  108 , an object placement storage unit  109 , an object display control unit  111 , an object selection detecting unit  112 , an object determining unit  113 , and a cursor movement invalidating unit  114 . 
     The clickable touch sensor  100  includes a touch sensor  101  and a mechanical switch  102 . 
     The touch sensor  101  is a device having variable flexibility with the pressure of the user&#39;s finger in a pressing direction, and has a property of increasing the number of touch positions to be detected according to the magnitude of the pressure of the user&#39;s finger. 
     The switch  102  is placed vertically downward with respect to an operation surface of the touch sensor  101  (that is, back side of the touch sensor  101 ). When the user presses the touch sensor  101  with the pressure higher or equal to a predetermined value, the switch  102  is also pressed down to be turned ON. 
     The touch information detecting unit  103  detects a touch position when the user&#39;s finger is in contact with the touch sensor  101  and the number of touch positions corresponding to the pressure to the touch sensor  101 . 
     The screen display device  500  includes a display screen, such as a liquid crystal display. On the display screen included in the screen display device  500 , a GUI screen that is an operation screen of an electronic device operated by the clickable touch sensor  100  is displayed. 
     The cursor position calculating unit  106  calculates a position of a cursor on the GUI screen to be displayed on the screen display device  500 . 
     The cursor display control unit  108  displays, on the GUI screen, a cursor at the position calculated by the cursor position calculating unit  106 . 
     The object placement storage unit  109  stores object placement information of each object, such as an icon, a button, and a menu. The object placement information indicates how to place the object on the GUI screen. 
     The object display control unit  111  displays each object on the GUI screen based on the object placement information. 
     The object selection detecting unit  112  detects an object currently selected by the user from among a plurality of objects displayed on the GUI screen, based on the position of the cursor. The object determining unit  113  determines the object detected by the object selection detecting unit  112 , when the user pressed the switch  102  of the clickable touch sensor  100 . 
     When the user performs a determination operation on the object currently selected by the user, the cursor movement invalidating unit  114  detects a pressing operation of the user before the user presses the touch sensor  101  to turn ON the switch  102  and the pressing information is output, and invalidates movement of the cursor on the GUI screen during a period from detection of the pressing operation to turning OFF of the switch  102 . 
       FIG. 19  is an external view of a GUI screen of a conventional information input device. 
     As illustrated in  FIG. 19 , a GUI screen  105  for operating an electronic device is displayed on the screen display device  500 . 
     On the GUI screen  105 , a cursor  107 , and objects  110 ( a ) to  110 ( c ) are displayed. 
     The cursor  107  is displayed on the GUI screen  105 , and is operated as a pointer by the information input device. 
     The operations performed by the information input system using a clickable touch sensor having the conventional misclick prevention function with the aforementioned configuration will be hereinafter described. 
     Here, a series of operations performed by the user who selects and determines (executes) the target object  110 ( b ) from among the objects  110 ( a ) to  110 ( c ) placed on the GUI screen  105  displayed by the screen display device  500  will be described with reference to  FIG. 19 . 
     When the user traces the touch sensor  101  to move the cursor  107  displayed on the GUI screen  105 , the touch information detecting unit  103  detects the position that is in contact with the user&#39;s the finger on the touch sensor  101 . 
     The cursor position calculating unit  106  determines a position of the cursor  107  to be displayed on the GUI screen  105 , based on the touch position obtained by the touch information detecting unit  103 . 
     The cursor display control unit  108  displays, on the GUI screen  105 , the cursor  107  at the position calculated by the cursor position calculating unit  106 . 
     Furthermore, the object selection detecting unit  112  determines whether or not the cursor  107  is on the display area of the objects  110 ( a ) to  110 ( c ) by reading, from the object placement storage unit  109 , the object placement information of each of the objects  110 ( a ) to  110 ( c ) displayed on the GUI screen  105  and comparing the object placement information with the position of the cursor obtained from the cursor position calculating unit  106 . 
     For example, when the cursor  107  is on a display area of the object  110 ( b ) as illustrated in the GUI screen of  FIG. 19 , the object selection detecting unit  112  determines that the cursor  107  is on the display area of the object  110 ( b ) and outputs an ID number of the object  110 ( b ) to the object display control unit  111 . 
     Upon receipt of the ID number of the object  110 ( b ) from the object selection detecting unit  112 , the object display control unit  111  displays the object  110 ( b ), for example, presents selection of the object  110 ( b ) by changing the size and color of the object  110 ( b ). 
     Furthermore, in order to determine the object  110 ( b ) selected by the user, when the touch sensor  101  is pressed down to turn ON the switch  102 , the switch  102  outputs the pressing information to the object selection detecting unit  112 . 
     Upon receipt of the pressing information from the switch  102 , the object selection detecting unit  112  outputs the ID number of the detected object  110 ( b ) to the object determining unit  113 . 
     Upon receipt of the ID number of the object  110 ( b ) from the object selection detecting unit  112 , assuming that the user determines the object  110 ( b ), the object determining unit  113  outputs the ID number to the object display control unit  111  and performs a determination process corresponding to the object  110 ( b ). 
     Upon receipt of the ID number of the object  110 ( b ) from the object determining unit  113 , the object display control unit  111  displays the object  110 ( b ), for example, presents determination of the object  110 ( b ) by changing the size and color of the object  110 ( b ). 
     Since the touch sensor  101  is a device having the variable flexibility in a pressing direction as described above, although the touch information detecting unit  103  detects only one touch position when the user lightly touches the touch sensor  101  with the finger, it can detect a plurality of touch positions corresponding to a predetermined pressure or more when the finger presses the touch sensor  101  with the pressure. 
     The cursor movement invalidating unit  114  determines whether or not the number of touch positions obtained from the touch information detecting unit  103  is larger than or equal to a predetermined value, and outputs cursor movement invalidating information to the cursor position calculating unit  106  when the number is larger. 
     Upon receipt of the cursor movement invalidating information, the cursor position calculating unit  106  continues to hold the position of the cursor  107  before receipt of the invalidating information without change from its receipt. 
     In other words, the cursor movement invalidating unit  114  determines that the user will perform an operation of pressing down the switch  102  when the user presses the touch sensor  101  with a predetermined pressure or more, and invalidates change in the position of the cursor  107  after the determination. 
     Thus, even when the user&#39;s finger is horizontally displaced by the pressure of pressing the switch  102 , the position of the cursor remains unchanged from the position before being pressed down. Thus, the cursor  107  is never horizontally displaced, or misclicked. 
     CITATION LIST 
     Patent Literature 
     
         
         [PTL 1] Japanese Unexamined Patent Application Publication No. 2000-311052 
         [PTL 2] Japanese Patent No. 4020246 
       
    
     SUMMARY OF INVENTION 
     Technical Problem 
     With the conventional configuration, an operation of pressing the switch  102  by the user&#39;s finger is detected only based on the pressure to the touch sensor  101 . Thus, even the user traces the touch sensor  101  with the finger at fast speed with slightly excessive force, there are cases where the cursor movement invalidating unit  114  determines the operation as the pressing operation and invalidates the cursor movement operation. 
     In particular, the user who is not familiar with the operation of the clickable touch sensor  100  cannot easily trace the touch sensor lightly. Thus, a problem that the cursor movement operation is frequently invalidated or suspended occurs. 
     Furthermore, the conventional configuration requires the touch information detecting unit  103  to detect information corresponding to pressure with which the user presses the touch sensor  101  with the finger, that is, detect the number of touch positions, in order to prevent misclick of the user on the clickable touch sensor  100 . 
     Thus, when a touch sensor having no change in the number of touch positions according to the pressure is used, there is another problem that misclick on the touch sensor cannot be prevented. 
     To sum up, although the touch sensor  101  that is a device having variable flexibility with the pressure of the user&#39;s finger can detect a plurality of touch positions when the user presses the touch sensor  101  with a predetermined pressure or more in the conventional example, a capacitive touch sensor that determines a touch position using change in a capacitance value between the finger and the touch sensor cannot obtain information corresponding to the pressure and prevent the misclick. 
     The present invention has been conceived to solve the conventional problems, and has an object of providing an information input device that can solve the problem of misclick on a clickable touch sensor without using information corresponding to the pressure of the user&#39;s finger. 
     Solution to Problem 
     In order to solve the conventional problems, an information input device according to an aspect of the present invention is an information input device including a clickable touch sensor including a touch sensor that can be vertically moved and a switch that is placed vertically downward with respect to an operation surface of the touch sensor and is pressed down by a user pressing the touch sensor, and the information input device includes: a touch information detecting unit configured to detect a touch information item obtained when a finger of the user is in contact with the touch sensor; a touch information sequence storage unit configured to store the touch information item for a predetermined period; and a pressing start position estimating unit configured to estimate a pressing start position at which the user started to press the touch sensor with the finger, based on touch information items stored in the touch information sequence storage unit, when the switch was pressed down, the touch information items including the touch information item. 
     With the configuration, when the user presses the switch of the clickable touch sensor for performing a determination operation on the object, the pressing start position estimating unit estimates a position at which the user originally desired to press the switch, based on the touch information item stored in the touch information sequence storage unit. An information input device having a misclick prevention function in which the operability is more improved can be provided using the estimated position as a correct pressing position instead of the position at which the switch is completely pressed down. Furthermore, since the pressing start position is estimated from the touch positions and times corresponding to the touch positions that are stored in the touch information sequence storage unit, it is possible to provide the information input device having the misclick prevention function and including a general touch sensor that cannot output information corresponding to the pressure of the user&#39;s finger. 
     Preferably, the information input device may further include a cursor position calculating unit configured to calculate a position of a cursor on a graphical user interface (GUI) screen, based on the touch information items stored in the touch information sequence storage unit or the pressing start position estimated by the pressing start position estimating unit. 
     Preferably, the information input device may further include: an object placement storage unit configured to store object placement information indicating an area of the GUI screen in which at least one object is placed; an object display control unit configured to display the at least one object on the GUI screen based on the object placement information obtained from the object placement storage unit; and an object selection detecting unit configured to detect an object selected by the user from among the at least one object, based on the object placement information and the position of the cursor obtained from the cursor position calculating unit. 
     The information input device may further include a misclick correction control unit configured to determine whether or not the pressing start position estimating unit estimates the pressing start position, based on object placement information of the object detected by the object selection detecting unit and the position of the cursor obtained from the cursor position calculating unit. 
     With the configuration, the information input device can determine whether or not estimation of a pressing start position is necessary, and perform a process of estimating the pressing start position only when necessary. Thus, the information input device can improve a response speed of a whole input operation. In particular, when the size of an object on the GUI screen is sufficiently larger than the maximum displacement width caused by the misclick, it is less likely that the erroneous operation is performed. Thus, the response speed of a whole input operation can be more improved than that according to Embodiment 1. 
     The information input device may further include a misclick correction control unit configured to determine whether or not the pressing start position estimating unit estimates the pressing start position, based on object placement information between a first object detected by the object selection detecting unit and at least one second object closer to the first object. 
     As such, the misclick correction control unit dynamically changes a threshold for determining whether or not the misclick correction is to be performed, based on a placement relationship between an object selected by the user and an object closer to the selected object. Thus, the information input device with a superior response speed and less erroneous operation caused by the misclick can be provided. 
     Preferably, the pressing start position estimating unit may include: a pressing start time estimating unit configured to estimate a pressing start time at which the user started to press the touch sensor with the finger, based on the touch information items stored in the touch information sequence storage unit, when the switch was pressed down; and a touch position determining unit configured to determine a contact position between the finger of the user and the touch sensor at the pressing start time, with reference to the touch information items stored in the touch information sequence storage unit. 
     Specifically, the pressing start time estimating unit may include: a movement amount calculating unit configured to calculate at least one type of an amount of movement of the finger on the touch sensor, based on the touch information items stored in the touch information sequence storage unit; and a stop time detecting unit configured to estimate a time at which the finger stopped, based on the amount of movement. 
     More specifically, each of the touch information items may include a touch position that is a position at which the finger was in contact with the touch sensor, the movement amount calculating unit may be configured to calculate a movement speed of the finger as the amount of movement, using a first touch position and a second touch position that are included in the touch information items, and the stop time detecting unit may be configured to determine, as the time at which the finger stopped, a time at which the movement speed is lower than or equal to a predetermined value to estimate the determined time as the pressing start time. 
     Accordingly, it is possible to estimate a pressing start position at which the user originally desired to press the touch sensor, based on coordinates at which the movement speed of the finger with which the user operates the touch sensor is lower than or equal to a threshold for the first time, and perform processing assuming that the clickable touch sensor is clicked at the estimated position. Thus, it is possible to provide an information input device with a misclick prevention function in which the operability can be more improved than that of the conventional information input device, using a general touch sensor that cannot output information corresponding to the pressure of the user&#39;s finger. 
     Furthermore, the pressing start time estimating unit may further include: a touch area calculating unit configured to determine a touch area that is an area of the touch sensor in contact with the finger, based on the touch information items stored in the touch information sequence storage unit; a pressed area arrival time detecting unit configured to determine a pressed area arrival time at which the touch area obtained from the touch area calculating unit reached a predetermined threshold; and a pressing start time determining unit configured to determine the pressing start time at which the user started to press the touch sensor with the finger, using the time estimated by the stop time detecting unit and the pressed area arrival time determined by the pressed area arrival time detecting unit. 
     Accordingly, it is possible to estimate a pressing start position at which the user originally desired to press the touch sensor, based on change in an area that is in contact with the finger and the touch sensor when the clickable touch sensor was pressed, in addition to the movement speed of the finger, and perform processing assuming that the clickable touch sensor is clicked at the estimated position. Thus, it is possible to reduce an erroneous operation caused by the misclick with higher accuracy. 
     Furthermore, the pressing start time estimating unit may include: a movement amount calculating unit configured to calculate at least one type of an amount of movement of the finger on the touch sensor, based on the touch information items stored in the touch information sequence storage unit; and a misclick start time detecting unit configured to detect presence or absence of misclick of the finger on the touch sensor, using the amount of movement, and determine, when detecting the presence of the misclick, a time immediately previous to a time at which the user misclicked. 
     Specifically, the pressing start time estimating unit may further include a moving direction calculating unit configured to calculate a moving direction of the finger on the touch sensor, based on the touch information items stored in the touch information sequence storage unit, and the misclick start time detecting unit may be configured to detect the presence or absence of the misclick of the finger on the touch sensor, using the amount of movement obtained from the movement amount calculating unit and the moving direction obtained from the moving direction calculating unit, and determine, when detecting the presence of the misclick, a time immediately previous to the time at which the user misclicked, using the amount of movement and the moving direction. 
     Thus, even when it is difficult to accurately detect a stop state of the finger after the user started to press the touch sensor, since the movement amount of the user&#39;s finger is relatively small, the information input device can detect abrupt change in a moving direction of the finger in addition to a movement speed of the finger, and using the detected information, detect the misclick and estimate the pressing start time with higher accuracy. 
     Furthermore, the pressing start time estimating unit may further include: a touch area calculating unit configured to determine a touch area that is an area of the touch sensor in contact with the finger, based on the touch information items stored in the touch information sequence storage unit; and a pressed area arrival time detecting unit configured to determine a pressed area arrival time at which the touch area obtained from the touch area calculating unit reached a predetermined threshold, and the misclick start time detecting unit may be configured to detect the presence or absence of the misclick of the finger on the touch sensor, using the pressed area arrival time obtained from the pressed area arrival time detecting unit, the amount of movement obtained from the movement amount calculating unit, and the moving direction obtained from the moving direction calculating unit, and determine, when detecting the presence of the misclick, a time immediately previous to the time at which the user misclicked, using the amount of movement and the moving direction. 
     Thus, it is possible to more accurately detect a time at which the user stopped moving the finger to turn ON the switch and pressed the touch sensor with the fingertip, and calculate a pressing start time with higher accuracy by narrowing down the possible period during which the misclick may occur. Furthermore, it is possible to reduce the workload for detecting the misclick. Thus, it is possible to accurately determine a touch position at which the user started to press the touch sensor, reduce an erroneous operation caused by the misclick, and accelerate the processing for preventing the misclick. 
     An information input device according to another aspect of the present invention is an information input device including a clickable touch sensor including a touch sensor that can be vertically moved and a switch that is placed vertically downward with respect to an operation surface of the touch sensor and is pressed down by a user pressing the touch sensor, and the information input device includes: a touch information detecting unit configured to detect a touch information item obtained when a finger of the user is in contact with the touch sensor; a touch information sequence storage unit configured to store the touch information item for a predetermined period; an object placement storage unit configured to store object placement information indicating an area of a GUI screen in which at least one object is placed; an object display control unit configured to display the at least one object on the GUI screen based on the object placement information obtained from the object placement storage unit; a cursor position calculating unit configured to calculate a position of a cursor on the GUI screen, based on the touch information items stored in the touch information sequence storage unit; an object selection detecting unit configured to detect an object selected by the user from among the at least one object, based on the object placement information and the position of the cursor obtained from the cursor position calculating unit; and an object lock control unit configured to determine whether or not to prevent the user from selecting an object other than the object detected by the object selection detecting unit, based on the touch information items stored in the touch information sequence storage unit. 
     Specifically, the object lock control unit may include: an object lock determining unit configured to perform an object lock determination process for determining whether or not to prevent the user from selecting the object other than the object detected by the object selection detecting unit, based on the touch information items stored in the touch information sequence storage unit; and an object lock determination process control unit configured to determine whether or not to perform the object lock determination process, based on placement information of the object detected by the object selection detecting unit and the position of the cursor obtained from the cursor position calculating unit. 
     In other words, even when the user moves the finger on the touch sensor and somewhat strongly presses the touch sensor, the user can successively input touch positions and improve the operability. Furthermore, according to Embodiments, a general touch sensor that can detect a position of a finger can prevent the misclick. 
     Furthermore, the object lock control unit may include: an object lock determining unit configured to perform an object lock determination process for determining whether or not to prevent the user from selecting the object other than the object detected by the object selection detecting unit, based on the touch information items stored in the touch information sequence storage unit; and an object lock determination process control unit configured to determine whether or not to perform the object lock determination process, based on placement information between a third object detected by the object selection detecting unit and at least one fourth object closer to the detected third object. 
     Accordingly, it is possible to provide an information input device that can lock an object that is a target that the user originally desired to press to prevent displacement of a pointer from the object, that performs a less erroneous operation caused by the misclick, and that has a superior response speed. 
     Preferably, the object lock determining unit may include: a movement amount calculating unit configured to calculate at least one type of an amount of movement of the finger on the touch sensor, based on the touch information items stored in the touch information sequence storage unit; and an object lock information generating unit configured to determine whether or not to prevent the user from selecting the object other than the object detected by the object selection detecting unit, based on the amount of movement, and generate object lock information according to a result of the determination. 
     Advantageous Effects of Invention 
     It is possible to provide an information input device that can solve the problem of misclick caused by a clickable touch sensor, without using information corresponding to the pressure of the user&#39;s finger. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is an external view of an information input system using an information input device according to Embodiment 1 in the present invention. 
         FIG. 2  is a block diagram illustrating a configuration of the information input device according to Embodiment 1. 
         FIG. 3  is a block diagram illustrating a configuration of a pressing start position estimating unit of the information input device according to Embodiment 1. 
         FIG. 4  is a flowchart of processes performed by the information input device according to Embodiment 1. 
         FIG. 5  illustrates a GUI screen according to Embodiment 1. 
         FIG. 6  is a block diagram illustrating a configuration of a pressing start position estimating unit according to Modification 1 of Embodiment 1. 
         FIG. 7  is a block diagram illustrating a configuration of a pressing start position estimating unit according to Modification 2 of Embodiment 1. 
         FIG. 8  is a block diagram illustrating a configuration of a pressing start position estimating unit according to Modification 3 of Embodiment 1. 
         FIG. 9  is a block diagram illustrating a configuration of an information input device according to Embodiment 2 in the present invention. 
         FIG. 10  is a flowchart of processes performed by the information input device according to Embodiment 2. 
         FIG. 11  illustrates an external view of a GUI screen according to Modification of Embodiment 2. 
         FIG. 12  is a block diagram of an information input device according to Embodiment 3 in the present invention. 
         FIG. 13  is a block diagram illustrating a configuration of an object lock control unit according to Embodiment 3. 
         FIG. 14  illustrates an external view of a GUI screen according to Embodiment 3. 
         FIG. 15  is a flowchart of processes performed by the information input device according to Embodiment 3. 
         FIG. 16  is an external view illustrating an exemplary computer system for implementing the information input device according to respective Embodiments 1 to 3 and Modifications in the present invention. 
         FIG. 17  is an external view illustrating a hardware configuration of a computer system for implementing the information input device according to respective Embodiments 1 to 3 and Modifications in the present invention. 
         FIG. 18  is a block diagram illustrating a configuration of an information input device according to a related art of the present invention. 
         FIG. 19  is an external view of a GUI screen of the information input device according to the related art. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Embodiments according to the present invention will be described with reference to the drawings. 
     Embodiment 1 
       FIG. 1  is an external view of an information input system using an information input device according to Embodiment 1 in the present invention. 
     As illustrated in  FIG. 1 , the information input system includes an information input device  200  and a screen display device  300 . 
     The information input device  200  is an operation device for operating a GUI screen  7  displayed by the screen display device  300 . 
     The screen display device  300  is a display device for displaying the GUI screen  7  for operating an electronic device. 
     The information input device  200  includes a clickable touch sensor  1  as a sensor for receiving an operation of the user&#39;s finger. Furthermore, the clickable touch sensor  1  includes a touch sensor  2  and a switch  3 . 
     The user moves the finger in contact with the touch sensor  2  included in the clickable touch sensor  1  as a conventional touch sensor so that a cursor on the GUI screen  7  can be moved. 
     The touch sensor  2  can be vertically moved with a spring configuration supported from the back side. Furthermore, the switch  3  is placed vertically downward with respect to the operation surface of the touch sensor  2 , and is pressed down by the user pressing the touch sensor  2 . In other words, the user can operate the switch  3  installed on the back side of the touch sensor  2  (ON-OFF operation) by pressing the touch sensor  2  with the finger or moving the finger off the touch sensor  2 . Accordingly, the user can perform an operation called a click operation without moving the finger off the touch sensor  2  under the GUI environment. 
     The screen display device  300  includes a screen display unit  6  and a screen control unit  400 . 
     The screen display unit  6  is a display device, such as a liquid crystal display. On the screen display unit  6 , the GUI screen  7  for operating (i) an electronic device operated by the information input device  200 , such as AV equipment including a television and a digital video recorder (DVR), and a personal computer (PC) and (ii) information equipment such as a mobile phone is displayed. 
     Furthermore, objects, such as icon buttons and menus, and a cursor  9  for pointing these are displayed on the GUI screen  7 . 
     The screen control unit  400  is a control unit that generates the GUI screen  7  and displays the GUI screen  7  on the screen display unit  6 . 
       FIG. 2  is a block diagram of an information input device  200  according to Embodiment 1 in the present invention. 
     As illustrated in  FIG. 2 , the information input device  200  includes the clickable touch sensor  1 , a touch information detecting unit  4 , a touch information sequence storage unit  5 , a cursor position calculating unit  8 , a cursor display control unit  10 , an object placement storage unit  11 , an object display control unit  13 , an object selection detecting unit  14 , an object determining unit  15 , and a pressing start position estimating unit  16 . 
     The clickable touch sensor  1  is a sensor that inputs an operation with the user&#39;s finger as described above. 
     The touch sensor  2  is a device that detects a position at which the finger is in contact with the surface of the touch sensor  2 , and outputs an electronic signal corresponding to the touched position. 
     Although the type for detecting the user&#39;s finger by the touch sensor  2  may be any of a capacitive type, a resistive type, a surface acoustic wave type, an infrared type, an electromagnetic induction type, and so on, Embodiment 1 will be described using a capacitive touch sensor of the capacitive type. 
     The switch  3  is, for example, a mechanical switch, and alternately switches between an ON state and an OFF state with a pressing operation. 
     The switch  3  is placed vertically downward with respect to the input surface of the touch sensor  2  (that is, back side of the touch sensor  2 ). The clickable touch sensor  1  is constructed in such a manner that when the user presses the touch sensor  2  with a pressure of a predetermined value or more, the switch  3  is also pressed down and is turned ON, with the spring configuration and others supporting the touch sensor  2 . 
     In order to reduce the thickness of the device, a piezoelectric sensor that is turned ON with a predetermined pressure or more that is equivalent to a force for pressing a spring may be used instead of a mechanical switch. 
     The touch information detecting unit  4  detects a touch information item obtained when the user&#39;s finger is in contact with the touch sensor  2 , using the electronic signal obtained from the capacitive touch sensor  2 . 
     The touch information item is, for example, a touch position at which the user&#39;s finger is in contact with the touch sensor  2 , and a capacitive value that varies according to a touch time at which the user&#39;s finger is in contact with the touch sensor  2  and a touch area in which the finger is in contact with the touch sensor  2 . 
     The touch information sequence storage unit  5  stores the touch information item detected by the touch information detecting unit  4  during a predetermined period. 
     The cursor position calculating unit  8  calculates a position of the cursor  9  (see  FIG. 5  to be described later) to be displayed on the GUI screen  7 . 
     The cursor display control unit  10  displays, on the GUI screen  7 , the cursor  9  at the position calculated by the cursor position calculating unit  8 . 
     The object placement storage unit  11  stores object placement information of each of objects  12 ( a ) to  12 ( c ), such as an icon, a button, and a menu. The object placement information indicates how to place the object on the GUI screen  7  in  FIG. 5 . 
     Specifically, the object placement information is a position at which the object should be displayed on the GUI screen  7 , and is expressed by, for example, two-dimensional or three-dimensional coordinates. 
     The object display control unit  13  displays each of the objects  12 ( a ) to  12 ( c ) on the GUI screen  7  based on the object placement information obtained from the object placement storage unit  11 . Specifically, the object display control unit  13  reads the object placement information of each of the objects  12 ( a ) to  12 ( c ) stored in the object placement storage unit  11 , and displays the object on the GUI screen  7  based on the corresponding object placement information. 
     Furthermore, the object display control unit  13  presents, to the user, the selection of the object by changing a size, a color, and others of the object currently selected by the user. 
     The object selection detecting unit  14  detects the object currently selected by the user from among the objects  12 ( a ) to  12 ( c ) displayed on the GUI screen, based on the position of the cursor  9 . 
     The object determining unit  15  determines the object detected by the object selection detecting unit  14 , when the user pressed the switch  3  of the clickable touch sensor  1 . Specifically, the object determining unit  15  outputs an ID number of the object to the object display control unit  13 . Furthermore, the object determining unit  15  performs a determination process corresponding to the object as necessary. 
     When the user pressed the switch  3  on the GUI screen  7  for determining the object selected by the user, the pressing start position estimating unit  16  estimates a pressing start position that is a touch position at which the user started to press the touch sensor  2  with the finger, based on the touch information item stored in the touch information sequence storage unit  5 . 
       FIG. 5  illustrates the GUI screen  7  according to Embodiment 1. 
     As illustrated in  FIG. 5 , the cursor  9  and the objects  12 ( a ) to  12 ( c ) are displayed on the GUI screen  7 . 
     The GUI screen  7  is an operation environment using a GUI for operating an electronic device operated by the information input device  200 . 
     The cursor  9  is displayed on the GUI screen  7 , and points to an object on the GUI screen  7  as a pointer based on output from the information input device  200 . 
     Each of the objects  12 ( a ) to  12 ( c ) is, for example, an icon, a button, and a menu used in the GUI environment. 
     Next,  FIG. 3  is a block diagram illustrating a configuration of the pressing start position estimating unit  16  according to Embodiment 1. 
     As illustrated in  FIG. 3 , the pressing start position estimating unit  16  includes a pressing start time estimating unit  20  and a touch position determining unit  23 . 
     The pressing start time estimating unit  20  estimates a pressing start time at which the user started to press the touch sensor  2  with the finger, based on the touch information item stored in the touch information sequence storage unit  5 . 
     The touch position determining unit  23  determines a contact position between the user&#39;s finger and the touch sensor  2  at the pressing start time, with reference to the pressing start time obtained from the pressing start time estimating unit  20  and the touch information item (touch time and touch position) stored in the touch information sequence storage unit  5 . 
     Then, the touch position determining unit  23  estimates the position as the pressing start position at which the user started to press the touch sensor  2  with the finger, and outputs the position to the cursor position calculating unit  8 . 
     The pressing start time estimating unit  20  includes a movement amount calculating unit  21  and a stop time detecting unit  22 . 
     The movement amount calculating unit  21  calculates at least one type of an amount of movement of the user&#39;s finger on the touch sensor  2 , based on the touch information item stored in the touch information sequence storage unit  5 . Examples of the amount of movement include a movement distance, a movement speed, and a movement acceleration of the user&#39;s finger on the touch sensor  2  for a predetermined period. For example, the movement amount calculating unit  21  calculates a movement speed of the finger as the amount of movement, using a first touch position and a second touch position that are included in the touch information items. 
     The stop time detecting unit  22  determines a time at which the user&#39;s finger stopped on the touch sensor  2 , using the amount of movement obtained from the movement amount calculating unit  21 . For example, the stop time detecting unit  22  determines, as the time at which the finger stopped, a time at which the movement speed is lower than or equal to a predetermined value to estimate the determined time as the pressing start time. 
       FIG. 4  is a flowchart of processes performed by the information input device according to Embodiment 1. 
     The operations performed by the information input device with the aforementioned configuration according to Embodiment 1 will be hereinafter described. Here, a series of operations in which the user selects and determines (executes), using the clickable touch sensor  1 , the target object  12 ( b ) from among the objects  12 ( a ) to  12 ( c ) placed on the GUI screen  7  displayed by the screen display unit  6  will be described as a specific example. 
     When the user traces the surface of the touch sensor  2  to move the cursor  9  displayed on the GUI screen  7 , the touch information detecting unit  4  detects, from the touch sensor  2 , the position (touch position) and the time (touch time) at which the user&#39;s finger is in contact with the touch sensor  2 , and a capacitive value when the finger is in contact with the touch sensor  2  (S 201 ), and sequentially stores the position, the time, and the value in the touch information sequence storage unit  5  (S 203 ). 
     Furthermore, the cursor position calculating unit  8  calculates the position of the cursor  9  to be displayed on the GUI screen  7 , using at least one touch position stored in the touch information sequence storage unit  5  (S 205 ). For example, the cursor position calculating unit  8  calculates the position of the cursor  9  to be displayed on the GUI screen  7 , using the latest touch position. 
     Next, the cursor display control unit  10  displays, on the GUI screen  7  of the screen display unit  6 , the cursor  9  at the position calculated by the cursor position calculating unit  8 . Furthermore, the object display control unit  13  reads the object placement information of each of the objects  12 ( a ) to  12 ( c ) stored in the object placement storage unit  11 , and displays the object on the GUI screen  7  of the screen display unit  6  based on the corresponding object placement information. 
     Next, the object selection detecting unit  14  reads the object placement information of each of the objects  12 ( a ) to  12 ( c ) displayed on the GUI screen  7 , from the object placement storage unit  11 . Then, the object selection detecting unit  14  compares the read object placement information with the position of the cursor obtained from the cursor position calculating unit  8  to determine whether or not the cursor  9  is on the display area of each of the objects (S 207 ). 
     When the cursor  9  is on the display area of any one of the objects  12 ( a ) to  12 ( c ) (Yes at S 207 ), the object selection detecting unit  14  determines that the user selects the corresponding object and outputs an ID number of the object to the object display control unit  13 . 
     Upon receipt of the ID number of the object from the object selection detecting unit  14 , the object display control unit  13  displays the object corresponding to the ID number, for example, presents selection of the object to the user by changing the size and color of the object. More specifically, the object display control unit  13  enlarges the size of the object corresponding to the ID number provided from the object selection detecting unit  14 . 
     When the object selection detecting unit  14  determines that the cursor  9  is not on the display area of the object (No at S 207 ), the cursor display control unit  10  informs the touch information detecting unit  4  to start the processes again (S 201 ). 
     The processes will be more specifically described with reference to  FIG. 5 . 
     Assume that the user moves the cursor  9  to the object  12 ( b ) on the GUI screen  7  by moving the finger on the touch sensor  2 . 
     Here, the object selection detecting unit  14  determines that the cursor  9  is on the display area of the object  12 ( b ) (Yes at S 207 ), and outputs the ID number of the object  12 ( b ) to the object display control unit  13 . 
     Next, upon receipt of the ID number of the object  12 ( b ) from the object selection detecting unit  14 , the object display control unit  13  displays the object  12 ( b ) on the GUI screen  7 , for example, presents selection of the object  12 ( b ) to the user by changing the size and color of the object (S 209 ). 
     Next, when the user presses down the touch sensor  2  for turning ON the switch  3  to determine the selected object (object  12 ( b ) in the former example) (Yes at S 211 ), the switch  3  outputs the pressing information to the pressing start position estimating unit  16 , the cursor position calculating unit  8 , and the object selection detecting unit  14 . 
     Upon receipt of the pressing information from the switch  3 , the pressing start position estimating unit  16  obtains, from the pressing start time estimating unit  20 , the pressing start time that is an estimated value of the time at which the user started to press the touch sensor  2  with the finger. 
     Furthermore, the touch position determining unit  23  determines a contact position between the finger and the touch sensor  2  at the pressing start time, with reference to the pressing start time obtained from the pressing start time estimating unit  20  and the touch information item stored in the touch information sequence storage unit  5  (S 215 ), and outputs, to the cursor position calculating unit  8 , the position as a pressing start position when the user started to press the touch sensor  2  with the finger. For example, assuming the pressing start time as Ts, the touch position (x(Ts), y(Ts)) at the time is output from the touch position determining unit  23  to the cursor position calculating unit  8  as a pressing start position. 
     Next, upon receipt of the pressing information from the switch  3 , the cursor position calculating unit  8  calculates the position of the cursor to be displayed on the GUI screen  7  using the pressing start position calculated by the pressing start position estimating unit  16 , instead of the touch position stored in the touch information sequence storage unit  5  (S 217 ). 
     Then, the object selection detecting unit  14  determines whether or not the position of the cursor  9  obtained by the cursor position calculating unit  8  is on the display area of an object (for example, each of the objects  12 ( a ) to  12 ( c )) in the same manner as when the switch  3  is not turned ON (S 219 ). 
     As a result, when the cursor  9  overlaps a display area of one of the objects  12 ( a ) to  12 ( c ) (Yes at S 219 ), the object selection detecting unit  14  determines that the user selects the corresponding object and outputs an ID number of the object (for example, object  12 ( b )) to the object determining unit  15  (S 221 ). 
     Upon receipt of the ID number of the object from the object selection detecting unit  14 , assuming that the user determines the object corresponding to the ID number, the object determining unit  15  outputs the ID number to the object display control unit  13 . Furthermore, the object determining unit  15  performs a determination process corresponding to the object as necessary. 
     Upon receipt of the ID number of the object from the object determining unit  15 , the object display control unit  13  displays the object corresponding to the ID number, for example, presents determination of the object to the user by changing the size and color of the object (S 223 ). 
     Next, the operations performed by the object determining unit  15  when the cursor  9  is on the display area of the object  12 ( b ) as illustrated in  FIG. 5  will be described as a specific example. 
     When the user pressed down the touch sensor  2  and turned ON the switch  3  to determine the object  12 ( b ) selected by the user, the object determining unit  15  assumes that the user determines the object  12 ( b ) corresponding to the ID number provided from the object selection detecting unit  14 . 
     As a result, the object determining unit  15  outputs the ID number of the object  12 ( b ) to the object display control unit  13 , and performs the determination process corresponding to the object  12 ( b ) (for example, when the object  12 ( b ) is an icon of an application, the object determining unit  15  starts the application). 
     Upon receipt of the ID number of the object  12 ( b ) from the object determining unit  15 , the object display control unit  13  displays the object  12 ( b ) on the GUI screen  7 , for example, presents determination of the object  12 ( b ) to the user by changing the size and color of the object. 
     Next, operations performed by the pressing start time estimating unit  20  according to Embodiment 1 will be described in detail. 
     First, the movement amount calculating unit  21  reads, from the touch information sequence storage unit  5 , touch positions and the touch times for a predetermined period from a time previous to a pressing time included in the pressing information, and determines at least one of types of amounts of movement, such as a movement distance, a movement speed, and a movement acceleration of the user&#39;s finger. 
     For example, (x(t), y(t)) denotes a touch position at a certain time t. 
     Assuming that T denotes a pressing time at which the user pressed the clickable touch sensor  1  (time when the switch  3  was actually turned ON), the movement amount calculating unit  21  calculates “n” movement speeds v(t) (t=T−1, T−2, . . . , T−n) that are amounts of movement for a predetermined period using Equation 1 below.
 
[Math 1]
 
 v ( t )=√{square root over (( x ( t )− x ( t− 1) 2 +( y ( t )− y ( t− 1)) 2 )}{square root over (( x ( t )− x ( t− 1) 2 +( y ( t )− y ( t− 1)) 2 )}{square root over (( x ( t )− x ( t− 1) 2 +( y ( t )− y ( t− 1)) 2 )}{square root over (( x ( t )− x ( t− 1) 2 +( y ( t )− y ( t− 1)) 2 )}  (Equation 1)
 
     Next, the stop time detecting unit  22  determines a time at which the user&#39;s finger stopped on the touch sensor  2 , using the amount of movement obtained by the movement amount calculating unit  21 , such as a movement distance, a movement speed, and a movement acceleration. 
     Specifically, the stop time is a time at which the amount of movement of the finger reaches a predetermined value or smaller. For example, when a movement speed is used as an amount of movement and Vs denotes a threshold of the movement speed at which the finger estimated as being stopped, a first time “t” that satisfies v(t)≦Vs from among the “n” movement speeds v(t) for a predetermined period is a stop time Ts. 
     The stop time may be the following time: 
     a time at which an amount of movement of the finger reaches a predetermined value or smaller and at which a time shorter than or equal to the predetermined value exceeds a predetermined time; 
     a time at which at least two types of amounts of movement of the finger reaches a predetermined value or smaller; or 
     a time at which at least two types of amounts of movement of the finger reaches a predetermined value or smaller and at which a time shorter than or equal to the predetermined value exceeds a predetermined time. 
     Finally, the stop time detecting unit  22  outputs the obtained stop time Ts as a pressing start time to the touch position determining unit  23 . 
     The operations performed by the pressing start time estimating unit  20  according to Embodiment 1 are described hereinbefore. 
     When the user pressed down the touch sensor  2  of the clickable touch sensor  1  and turned ON the switch  3  to determine the selected object, in the information input device according to Embodiment 1, the pressing start position estimating unit  16  can estimate a touch position of the user&#39;s finger when the user started to press the touch sensor  2 , based on “n” touch positions that are stored in the touch information sequence storage unit  5  for a predetermined period immediately before the user pressed the switch  3 . 
     In other words, the pressing start position estimating unit  16  uses the pressing start time that is an estimated time at which the user started to press the switch  3 , instead of the position of the finger when the switch  3  is actually turned ON. Accordingly, it is possible to prevent the misclick on the clickable touch sensor  1 . 
     Thus, even when the user&#39;s finger presses the switch  3  and the finger is slightly displaced by the pressure of the finger, the object selected by the user can be determined, and an erroneous operation caused by the misclick can be reduced. 
     Furthermore, a touch position changing operation can be performed by moving the finger on the touch sensor  2  unless the user completely presses down the switch  3  according to Embodiment 1. The method according to the present invention is different from a method for preventing the misclick by detecting an operation of the user who intends to press the switch  3  with pressure of the user&#39;s finger to the touch sensor  2  and invalidating the touch position changing operation, that is, a cursor movement operation on the GUI screen  7 , as performed by the conventional information input device. In other words, even when the user moves the finger on the touch sensor  2  and somewhat strongly presses the touch sensor  2 , the user can successively input touch positions, that is, continuously move the cursor  9  on the GUI screen  7 . Thus, the operability according to Embodiment 1 in the present invention can be more improved than that of the conventional information input device. 
     Furthermore, although the conventional information input device needs the special touch sensor  101  that can detect the pressure of the user&#39;s finger, the pressing start position estimating unit  16  merely estimates a pressing start position based on the touch position stored in the touch information sequence storage unit  5  according to Embodiment 1. Thus, the touch sensor  2  that is generally used for detecting a position of a finger can also prevent the misclick. 
     Specifically, even when the user presses down the switch  3  and the finger is slightly displaced by the pressure of the finger, the information input device  200  according to Embodiment 1 can reliably input a position at which the user intended to press the switch  3  and reduce an erroneous operation caused by the misclick. Furthermore, the information input device  200  can perform the touch position changing operation by moving the finger on the touch sensor  2  unless the user completely presses down the switch  3  according to Embodiment 1. The method according to the present invention is different from the method for preventing the misclick by detecting an operation of the user who intended to press the switch  3  with pressure of the user&#39;s finger to the touch sensor  2  and invalidating the touch position changing operation according to the movement of the user&#39;s finger, as performed by the conventional information input device. Thus, even when the user moves the finger on the touch sensor  2  and somewhat strongly presses the touch sensor  2 , the user can successively input touch positions. Thus, it is possible to provide the information input device with the misclick prevention function with which the operability has been more improved than that of the conventional technique. 
     Furthermore, the information input device  200  according to Embodiment 1 may be an information input device with a misclick prevention function using a general touch sensor that cannot output information corresponding to the pressure of the user&#39;s finger. 
     According to Embodiment 1, the pressing start time estimating unit  20  of the pressing start position estimating unit  16  may have a configuration illustrated in  FIGS. 6 to 8  to be described hereinafter, instead of the configuration illustrated in  FIG. 3 . 
     (Modification 1) 
       FIG. 6  is a block diagram illustrating a configuration of the pressing start time estimating unit  20  according to Modification 1 of Embodiment 1. In  FIG. 6 , the same constituent elements as those in  FIG. 3  according to Embodiment 1 are denoted by the same reference numerals, and the detailed description thereof is omitted. 
     As illustrated in  FIG. 6 , the pressing start time estimating unit  20  includes the movement amount calculating unit  21 , the stop time detecting unit  22 , a touch area calculating unit  24 , a pressed area arrival time detecting unit  25 , and a pressing start time determining unit  26 . 
     Here, the pressing start time estimating unit  20  according to Modification 1 is different from that according to Embodiment 1 in including the touch area calculating unit  24 , the pressed area arrival time detecting unit  25 , and the pressing start time determining unit  26 , which will be described hereinafter. 
     The touch area calculating unit  24  in  FIG. 6  determines an area which the user&#39;s finger is in contact with, based on the touch information item stored in the touch information sequence storage unit  5 . 
     The pressed area arrival time detecting unit  25  determines a time at which the user arrived at a pressed area that is a threshold of a touch area for determining that the user started to press the touch sensor  2 . The touch area is obtained from the touch area calculating unit  24 . 
     The pressing start time determining unit  26  determines the pressing start time at which the user started to press the touch sensor  2 , using a first time that is a stop time Ts and is obtained from the stop time detecting unit  22 , and a second time that is obtained from the pressed area arrival time detecting unit  25  and is a time at which the user arrived at the pressed area that is the threshold of the touch area for determining that the user started to press the touch sensor  2 . 
     The operations performed by the pressing start time estimating unit  20  with the aforementioned configuration will be described. 
     As described above, when the switch  3  provides the pressing information with the clickable touch sensor  1  pressed, the movement amount calculating unit  21  obtains, from the touch information sequence storage unit  5 , touch positions and the touch times for a predetermined period from a time previous to the pressing time of the pressing information. 
     Next, the movement amount calculating unit  21  determines at least one of types of amounts of movement, such as a movement distance, a movement speed, and a movement acceleration of the user&#39;s finger, using the touch positions and the touch times that are obtained. 
     Furthermore, the stop time detecting unit  22  determines the stop time Ts that is the first time at which the calculated amount of movement is smaller than or equal to a threshold. 
     Furthermore, the touch area calculating unit  24  reads, from the touch information sequence storage unit  5 , capacitive values for the predetermined period from the time previous to the pressing time of the pressing information, and determines a touch area of the touch sensor  2  in contact with the user&#39;s finger. For example, assuming that T denotes a pressing time and c(t) denotes a capacitive value at a certain time “t”, the touch area calculating unit  24  calculates “n” touch areas s(t) (t=T−1, T−2, . . . , T−n) using Equation 2 below.
 
[Math 2]
 
 s ( t )=α· c ( t ) β +γ  (Equation 2)
 
     Next, the pressed area arrival time detecting unit  25  determines a time at which the user arrived at the pressed area indicating the touch area estimated as an area at which the user started to press the touch sensor  2  with the finger (not moving the finger), using the touch area estimated by the touch area calculating unit  24 . 
     More specifically, the time at which the touch area is larger than or equal to a predetermined value is a pressed area arrival time. 
     For example, assuming that Sp denotes a threshold of the touch area that is an estimated area estimated when the user started to press the touch sensor  2  with the finger, Tp that is the first time “t” that satisfies s(t)≧Sp from among the “n” touch areas s(t) for the predetermined period is a pressed area arrival time. The pressed area arrival time may be determined when a touch area is larger than or equal to a predetermined value, and using a time at which the touch area continues for a predetermined period or longer. 
     Finally, the pressing start time determining unit  26  determines (estimates) the pressing start time at which the user started to press the touch sensor  2  with the finger, based on the stop time Ts obtained from the stop time detecting unit  22  and the pressed area arrival time Tp obtained from the pressed area arrival time detecting unit  25 . 
     More specifically, the pressing start time determining unit  26  has only to select one of the stop time Ts and the pressed area arrival time Tp that is closer to the pressing time T that is a time when the switch  3  actually pressed, and determine the selected time as the pressing start time. 
     The pressing start time determining unit  26  may calculate an average between the stop time Ts and the pressed area arrival time Tp and determine the average as the pressing start time. 
     In the pressing start time estimating unit  20  according Modification 1 with such a configuration, the pressing start time determining unit  26  can determine the pressing start time at which the user started to press the touch sensor  2  with the finger, using the time at which movement of the user&#39;s finger stopped that is estimated by the stop time detecting unit  22  and a time which is detected by the pressed area arrival time detecting unit  25  and at which the touch area of the user&#39;s finger in contact with the touch sensor  2  exceeds a predetermined pressed area. 
     Thus, after the user stopped the movement of the finger to turn ON the switch  3 , the pressing start time estimating unit  20  can accurately detect an operation of pressing the touch sensor  2  with the fingertip to press the touch sensor  2 , and calculate a pressing start time with higher accuracy than that in  FIG. 3  according to Embodiment 1. 
     Thus, the pressing start time estimating unit  20  can accurately determine a touch position at which the user started to press the touch sensor  2  with the finger, and reduce an erroneous operation caused by the misclick with higher accuracy according to Modification 1 than that in  FIG. 3  according to Embodiment 1. 
     The operations performed by the pressing start time estimating unit  20  according to Modification 1 of Embodiment 1 are described hereinbefore. 
     Next, Modification 2 of Embodiment 1 will be described. 
     (Modification 2) 
       FIG. 7  is a block diagram illustrating a configuration of the pressing start time estimating unit  16  according to Modification 2 of Embodiment 1. In  FIG. 7 , the same constituent elements as those in  FIGS. 3 and 6  according to Embodiment 1 are denoted by the same reference numerals, and the detailed description thereof is omitted. 
     As illustrated in  FIG. 7 , the pressing start time estimating unit  20  according to Modification 2 includes the movement amount calculating unit  21 , the stop time detecting unit  22 , a moving direction calculating unit  30 , and a misclick start time detecting unit  31 . 
     The difference between  FIG. 7  according to Modification 2 and  FIG. 3  according to Embodiment 1 is that the pressing start time estimating unit  20  further includes the moving direction calculating unit  30  and the misclick start time detecting unit  31 . 
     These constituent elements will be described hereinafter. 
     The moving direction calculating unit  30  calculates a moving direction of the user&#39;s finger on the touch sensor  2 , based on the touch information item stored in the touch information sequence storage unit  5 . 
     The misclick start time detecting unit  31  detects the presence or absence of misclick by the user&#39;s finger on the touch sensor  2 , using at least one type of an amount of movement obtained from the movement amount calculating unit  21  (for example, movement speed or movement acceleration), the moving direction obtained from the moving direction calculating unit  30 , and the stop time estimated as a time at which the user&#39;s finger estimated as being stopped on the touch sensor  2  and is obtained from the stop time detecting unit  22 . 
     Furthermore, when detecting misclick, the misclick start time detecting unit  31  determines a time immediately previous to the time when the user misclicked, and outputs the time as the pressing start time when the user&#39;s finger started to touch the touch sensor  2 . 
     The operations performed by the pressing start time estimating unit  20  with the aforementioned configuration will be described. 
     First, upon receipt of the pressing information with the switch  3  pressed as described above, the movement amount calculating unit  21  obtains, from the touch information sequence storage unit  5 , the touch positions and the touch times for a predetermined period from a time previous to the pressing time of the pressing information. 
     Next, the movement amount calculating unit  21  determines one of types of amounts of movement, such as a movement distance, a movement speed, and a movement acceleration of the user&#39;s finger, using the touch positions and the touch times that are obtained. 
     Next, upon receipt of the amount of movement from the movement amount calculating unit  21 , the stop time detecting unit  22  determines a time at which it is estimated that the user&#39;s finger stopped on the touch sensor  2 , using the movement amount. 
     Specifically, the stop time is a time at which the amount of movement of the finger reaches a predetermined value or smaller. For example, when a movement speed is used as an amount of movement and Vs denotes a threshold of the movement speed at which the finger estimated as being stopped, a first time “t” that satisfies v(t)≦Vs from among the “n” movement speeds v(t) for a predetermined period is a stop time Ts. 
     Furthermore, the moving direction calculating unit  30  obtains, from the touch information sequence storage unit  5 , the touch positions and the touch times for the predetermined period from a time previous to the pressing time of the pressing information. 
     Next, the moving direction calculating unit  30  determines a moving direction of the user&#39;s finger on the touch sensor  2 , using the touch positions and the touch times that are obtained. For example, assuming that T denotes a pressing time and (x(t), y(t)) denotes a touch position at a certain time “t” using x and y coordinates, the moving direction calculating unit  30  calculates “n” moving directions θ(t) (t=T−1, T−2, . . . , T−n) for a predetermined period before T using Equation 3 below. 
                   [     Math   ⁢           ⁢   3     ]                             θ   ⁡     (   t   )       =       cos     -   1       ⁡     (         P   ⁡     (   t   )       ·     P   ⁡     (     t   -   1     )                  P   ⁡     (   t   )            ⁢          P   ⁡     (     t   -   1     )                )               (     Equation   ⁢           ⁢   3     )               
in the case where P(t)=(x(t)−x(t−1), y(t) y(t−1) is satisfied.
 
     P(t)·P(t−1) expresses an inner product of vectors P(t) and P(t−1), and ∥P(t)∥ expresses a norm of the vector P(t). 
     Next, the misclick start time detecting unit  31  detects whether or not the user misclicked when the user pressed down the touch sensor  2  with the finger, using the amount of movement obtained from the movement amount calculating unit  21 , the moving direction obtained from the moving direction calculating unit  30 , and the stop time detected by the stop time detecting unit  22 . 
     Specifically, the misclick start time detecting unit  31  estimates that the misclick has occurred when each of the amount of movement and the moving direction of the user&#39;s finger is larger than or equal to a predetermined value, during a period from the stop time Ts at which the user&#39;s finger is estimated as being stopped to the pressing time T at which the switch  3  was pressed down. 
     For example, assuming that a movement speed v(t) denotes an amount of movement of the user&#39;s finger (see Equation 1), θ(t) denotes a moving direction of the user&#39;s finger, Vb denotes a threshold of the movement speed at which the user&#39;s finger is estimated as having misclick, and Θb denotes a threshold of the moving direction in which the user&#39;s finger is estimated as having misclick, when v(t) and θ(t) satisfy a misclick condition as expressed by Expression 4 below during a period from the time Ts to the time (T−1), the misclick start time detecting unit  31  estimates that the user misclicked with the finger.
 
[Math 4]
 
 v ( t )&gt; Vb  and θ( t )&gt;Θ b   (Expression 4)
 
     The condition for detecting misclick may be a condition under which the misclick state continues for more than a predetermined period. 
     When detecting the misclick, the misclick start time detecting unit  31  determines a time Tb immediately previous to the detection of the misclick and outputs the time Tb as a pressing start time, where Ts&lt;Tb&lt;T−1. For example, the time Tb is a time the closest to Ts from among the times “t” that satisfy Expression 4. 
     In the pressing start time estimating unit  20  according to Modification 2, the misclick start time detecting unit  31  detects whether or not the user&#39;s finger was displaced (the user misclicked), using an amount of movement and a moving direction of the finger, and outputs a time immediately previous to the misclick as a pressing start time only when detecting the misclick. 
     In other words, the misclick start time detecting unit  31  according to Modification 2 determines, as misclick, abrupt change in an amount of movement and a moving direction of the user&#39;s finger after the user&#39;s finger is in a stop state, and detects, as a pressing start time, the time immediately previous to occurrence of the misclick. 
     Thus, even when it is difficult to accurately detect the stop state of the finger after the user started to press the touch sensor  2 , since the amount of movement of the user&#39;s finger is relatively small, the misclick start time detecting unit  31  can determine the pressing start time with higher accuracy. 
     For example, when a larger number of objects are displayed on the GUI screen  7 , the user needs to accurately select a target object among them. Here, the amount of movement of the user&#39;s finger on the touch sensor  2  is relatively small. Thus, it is very difficult to detect a time at which the movement of the finger stopped. 
     However, the configuration for detecting the abrupt change in a moving direction in addition to an amount of movement to estimate a stop time according to Modification 2 enables reduction in an erroneous operation caused by misclick. 
     Although the misclick start time detecting unit  31  detects misclick using both feature quantities of the amount of movement and the moving direction, it may detect the misclick using only one of the feature quantities. 
     The pressing start time estimating unit  20  according to Modification 2 does not necessarily have to include the stop time detecting unit  22 . In such a case, for example, the misclick start time detecting unit  31  obtains the calculated amount of movement from the movement amount calculating unit  21 , and determines whether or not the amount of movement is smaller than or equal to a threshold. 
     Modification 2 of Embodiment 1 is described hereinbefore. 
     Next, Modification 3 of Embodiment 1 will be described. 
     (Modification 3) 
       FIG. 8  is a block diagram illustrating a configuration of the pressing start time estimating unit  20  according to Modification 3. In  FIG. 8 , the same constituent elements as those in  FIGS. 3 to 7  according to Embodiment 1 are denoted by the same reference numerals, and the detailed description thereof is omitted. 
     As illustrated in  FIG. 8 , the pressing start time estimating unit  20  according to Modification 3 includes the movement amount calculating unit  21 , the stop time detecting unit  22 , the moving direction calculating unit  30 , the touch area calculating unit  24 , the pressed area arrival time detecting unit  25 , and the misclick start time detecting unit  31 . 
     The difference between  FIG. 8  according to Modification 3 and  FIG. 7  according to Modification 2 is that the pressing start time estimating unit  20  further includes the touch area calculating unit  24  and the pressed area arrival time detecting unit  25 . Since the touch area calculating unit  24  and the pressed area arrival time detecting unit  25  have the same configuration as that in  FIG. 6 , the detailed description thereof is omitted and only the operations performed by the pressing start time estimating unit  20  with the configuration in  FIG. 8  will be described. 
     As already described for the operations in  FIG. 7  according to Modification 2, upon receipt of the pressing information from the switch  3 , the movement amount calculating unit  21  obtains, from the touch information sequence storage unit  5 , the touch positions and the touch times for a predetermined period from a time previous to the pressing time T of the pressing information. 
     Next, the movement amount calculating unit  21  determines at least one of types of amounts of movement, such as a movement distance, a movement speed, and a movement acceleration of the user&#39;s finger, using the touch positions and the touch times that are obtained. 
     Upon receipt of the amount of movement from the movement amount calculating unit  21 , the stop time detecting unit  22  determines a time at which it is estimated that the user&#39;s finger stopped on the touch sensor  2 , using the movement amount, and outputs the time as a stop time Ts. 
     Furthermore, the moving direction calculating unit  30  determines a moving direction of the user&#39;s finger on the touch sensor  2 , using the touch positions and the touch times that are stored in the touch information sequence storage unit  5  for the predetermined period from the time previous to the pressing time T of the pressing information. 
     As already described for the operations in  FIG. 6  according to Modification 1 of Embodiment 1, upon receipt of the pressing information from the switch  3 , the touch area calculating unit  24  obtains, from the touch information sequence storage unit  5 , capacitive values for the predetermined period from the time previous to the pressing time T of the pressing information. 
     Next, the touch area calculating unit  24  determines an area of the touch sensor  2  with which the user&#39;s finger is in contact, for each of the obtained times using the obtained capacitive values (see Equation 2). 
     Next, the pressed area arrival time detecting unit  25  determines a time at which the user arrived at the pressed area that is a threshold of a touch area for determining that the user started to press the touch sensor  2 , using the touch area calculated by the touch area calculating unit  24 , and outputs the time as the pressed area arrival time Tp. 
     Finally, the misclick start time detecting unit  31  compares the stop time Ts obtained from the stop time detecting unit  22  with the pressed area arrival time Tp obtained from the pressed area arrival time detecting unit  25 , and detects a time closer to the pressing time T of the switch  3 , as a misclick monitoring start time Tw. 
     Next, the misclick start time detecting unit  31  detects whether or not the misclick has occurred when the user presses the touch sensor  2  with the finger, using the amount of movement obtained from the movement amount calculating unit  21  and the moving direction obtained from the moving direction calculating unit  30 . 
     Specifically, the misclick start time detecting unit  31  estimates that the misclick has occurred when each of the amount of movement and the moving direction of the user&#39;s finger is larger than or equal to a predetermined value, during a period from the misclick monitoring start time Tw to the pressing time T at which the switch  3  was pressed. 
     For example, assuming that a movement speed v(t) denotes an amount of movement of the user&#39;s finger (see Equation 1), θ(t) denotes a moving direction of the user&#39;s finger, Vb denotes a threshold of the movement speed at which the user&#39;s finger was estimated as having the misclick, and Θb denotes a threshold of the moving direction in which the user&#39;s finger was estimated as having the misclick, when v(t) and θ(t) satisfy a misclick condition as expressed by Expression 5 below during a period from the time Tw to the time (T−1), the misclick start time detecting unit  31  estimates that the user misclicked with the finger.
 
[Math 5]
 
 v ( t )&gt; Vb  and θ( t )&gt;Θ b   (Expression 5)
 
     The condition for detecting misclick may be a condition under which the misclick state continues for more than a predetermined period. 
     When detecting the misclick, the misclick start time detecting unit  31  determines a time Tb immediately previous to the detection of the misclick, and outputs the time Tb as a pressing start time, where Tw&lt;Tb&lt;T−1. 
     For example, the time Tb is a time the closest to Tw from among the times “t” that satisfy Expression 5. 
     As described above, the misclick start time detecting unit  31  according to Modification 3 detects whether or not the user&#39;s finger misclicked on the touch sensor  2 , using an amount of movement and a moving direction of the user&#39;s finger, and outputs a time immediately previous to detection of the misclick as a pressing start time only when detecting the misclick. 
     Furthermore, the misclick start time detecting unit  31  according to Modification 3 detects misclick using an amount of movement and a moving direction of the user&#39;s finger, during a period from the time Tw to the time T. The time Tw is larger one of the stop time Ts at which movement of the finger stopped and the time Tp at which the touch area of the user&#39;s finger on the touch sensor  2  exceeds a predetermined pressed area. 
     Thus, according to Modification 3, it is possible to more accurately detect a time at which the user stopped moving the finger to turn ON the switch  3  and presses down the touch sensor  2  with the fingertip, and calculate a pressing start time with higher accuracy by narrowing down a possible period at which the misclick may occur. Furthermore, it is possible to reduce the workload for detecting the misclick. 
     Thus, it is possible to accurately determine a touch position at which the user started to press the touch sensor  2 , reduce an erroneous operation caused by the misclick, and accelerate the processing for preventing the misclick. 
     Modification 3 of Embodiment 1 is described herein before. 
     As described above according to Embodiment 1 and Modifications 1 to 3, the information input device  200  in  FIG. 2  does not have to include the cursor position calculating unit  8 , the cursor display control unit  10 , the object placement storage unit  11 , the object display control unit  13 , the object selection detecting unit  14 , and the object determining unit  15 . 
     When the information input device  200  does not include the cursor position calculating unit  8 , the cursor display control unit  10 , the object placement storage unit  11 , the object display control unit  13 , the object selection detecting unit  14 , and the object determining unit  15 , the screen control unit  400  may include the cursor position calculating unit  8 , the cursor display control unit  10 , the object placement storage unit  11 , the object display control unit  13 , the object selection detecting unit  14 , and the object determining unit  15 . 
     In this case, the information input device  200  transmits, to the cursor position calculating unit  8  included in the screen control unit  400 , at least one touch position stored in the touch information sequence storage unit  5 , via a wired or wireless line. Furthermore, the information input device  200  transmits the pressing information when the switch  3  is turned ON, to the cursor position calculating unit  8  and the object selection detecting unit  14  that are included in the screen control unit  400 . Furthermore, when the switch  3  is turned ON, the information input device  200  transmits a pressing start estimated position estimated by the pressing start position estimating unit  16 , to the cursor position calculating unit  8  included in the screen control unit  400 . 
     Even when the information input device  200  does not include the cursor position calculating unit  8  and the cursor display control unit  10 , with the configuration, the cursor position calculating unit  8  can calculate a position of the cursor to be displayed on the GUI display  7 , and the cursor display control unit  10  can display the cursor at the calculated position on the GUI display  7 . 
     Even when the information input device  200  does not include the object placement storage unit  11 , the object display control unit  13 , and the object selection detecting unit  14 , the object selection detecting unit  14  can detect an object selected by the user, based on the position of the cursor output from the cursor position calculating unit  8  and the object placement information stored in the object placement storage unit  11 , and the object display control unit  13  can display the selection of the object by obtaining an ID number of the selected object obtained from the object selection detecting unit  14 . 
     Furthermore, even when the information input device  200  does not include the object determining unit  15 , upon turning ON the switch  3 , the object selection detecting unit  14  receives the pressing information from the switch  3 , and outputs the ID number of the object selected at that time. Thus, the object determining unit  15  can determine (execute) the object. 
     Embodiment 1 and Modifications 1 to 3 regarding the information input device  200  including the pressing start position estimating unit that estimates a pressing start position at which the user turned ON the switch  3  are described hereinbefore. 
     Next, Embodiment 2 that further describes a misclick correction control unit that determines whether or not a pressing start position should be estimated will be described. 
     Embodiment 2 
       FIG. 9  is a block diagram of an information input device according to Embodiment 2 in the present invention. In  FIG. 9 , the same constituent elements as those in  FIG. 2  according to Embodiment 1 are denoted by the same reference numerals, and the detailed description thereof is omitted. 
     As illustrated in  FIG. 9 , the information input device  200  according to Embodiment 2 includes a clickable touch sensor  1 , a touch information detecting unit  4 , a touch information sequence storage unit  5 , a pressing start position estimating unit  16 , a misclick correction control unit  17 , a cursor position calculating unit  8 , a cursor display control unit  10 , an object placement storage unit  11 , an object display control unit  13 , an object selection detecting unit  14 , and an object determining unit  15 . 
       FIG. 9  according to Embodiment 2 is different from  FIG. 2  according to Embodiment 1 by including the misclick correction control unit  17 . The misclick correction control unit  17  will be described hereinafter. 
     The misclick correction control unit  17  determines, on the GUI display  7 , whether or not misclick correction is to be performed based on the object placement information detected by the object selection detecting unit  14  and the position of the cursor  9  obtained from the cursor position calculating unit  8 , and causes the pressing start position estimating unit  16  to estimate a pressing start position when determining to perform the misclick correction. 
     Next, a method for determining whether or not the misclick correction control unit  17  performs the misclick correction will be described. 
     The misclick correction control unit  17  determines whether or not to perform the misclick correction, based on whether or not it is highly possible that the object detected by the object selection detecting unit  14  based on the position of the cursor before the correction is identical to the object detected by the object selection detecting unit  14  based on the position of the cursor corrected by the pressing start position estimating unit  16 . 
     In other words, the misclick correction control unit  17  determines not to perform the misclick correction when it is highly possible that these objects are identical to each other, and otherwise, determines to perform the misclick correction. 
     Specifically, the misclick correction control unit  17  has only to define the maximum displacement width of the position of the cursor subject to misclick of the user&#39;s finger, and, even when the objects to be selected before and after correcting the current cursor position by the maximum displacement width are identical to each other, determine not to perform the misclick correction. 
     The processes will be more specifically described with reference to  FIG. 11 . As illustrated in  FIG. 11 , assume that on the GUI screen  7 , (X, Y) denotes the current cursor position, and (Rx, Ry, W, H) denotes placement information of the selected object  12 ( b ), where (Rx, Ry) denotes the lower left coordinate position of the object  12 ( b ), and W and H denote a width and a height of the object  12 ( b ), respectively. Furthermore, B denotes the maximum displacement width of the user&#39;s finger. 
     Here, when the cursor position (X, Y) before the correction satisfies the following Expression 6, the misclick correction control unit  17  determines not to perform the misclick correction.
 
[Math 6]
 
( Rx&lt;X−B ),( X+B&lt;Rx+W ),( Ry&lt;Y−B ), and ( Y+B&lt;Ry+H ).  (Expression 6)
 
     Here, the maximum displacement widths B for vertical and horizontal misclick are not set to a fixed value, and may be set to different values. 
     The procedure of the operations according to Embodiment 2 will be described with reference to  FIG. 10 . 
     Here, a series of operations in which the user selects and determines (executes), using the clickable touch sensor  1 , the target object  12 ( b ) from among the objects  12 ( a ) to  12 ( c ) placed on the GUI screen  7  displayed by the screen display unit  6  will be described as a specific example (see  FIG. 11 ). 
     As already described, the configuration according to Embodiment 2 is a configuration in which the misclick correction control unit  17  is added to the configuration in  FIG. 2  according to Embodiment 1. Each of the constituent elements in  FIG. 9  other than the misclick correction control unit  17  performs the same processing as that according to Embodiment 1. 
     Specifically, the operations performed by the constituent elements until the user selects the target object  12 ( b ) are identical to those according to Embodiment 1, in the series of operations in which the user selects and determines (executes), using the clickable touch sensor  1 , the target object  12 ( b ) from among the objects  12 ( a ) to  12 ( c ) placed on the GUI screen  7  displayed by the screen display unit  6 . 
     Here, the operations after pressing down the touch sensor  2  of the clickable touch sensor  1  and turning ON the switch  3  (Yes at S 211 ) in order to determine the object  12 ( b ) selected by the user on the GUI screen  7  will be described. 
     When the user pressed down the clickable touch sensor  1  to turn ON the switch  3  (Yes at S 211 ), the switch  3  outputs the pressing information to the misclick correction control unit  17 , the cursor position calculating unit  8 , and the object selection detecting unit  14 . 
     Upon receipt of the pressing information from the switch  3 , the misclick correction control unit  17  obtains an ID number of the object currently selected by the user (that is, overlapped by the cursor  9 ) (for example, object  12 ( b )) from the object selection detecting unit  14 . 
     Furthermore, the misclick correction control unit  17  reads the position of the object  12 ( b ) from the object placement storage unit  11  using the ID number obtained from the object selection detecting unit  14 . 
     Furthermore, the misclick correction control unit  17  obtains, from the cursor position calculating unit  8 , the current position of the cursor  9  on the GUI screen  7 , at the time when the misclick correction control unit  17  obtains the pressing information. 
     Then, the misclick correction control unit  17  determines whether or not to perform the misclick correction, using the object placement information and the cursor position of the object  12 ( b ) currently selected by the user (S 301 ). 
     When determining to perform the misclick correction (Yes at S 301 ), the misclick correction control unit  17  outputs misclick correction start information to the pressing start position estimating unit  16  and causes the pressing start position estimating unit  16  to perform the misclick correction. 
     Upon receipt of the misclick correction start information, the pressing start position estimating unit  16  estimates a pressing start position at which the user started to press the touch sensor  2  with the finger, based on the touch information item stored in the touch information sequence storage unit  5 , and outputs the pressing start position to the cursor position calculating unit  8  (S 302 ). 
     Then, the cursor position calculating unit  8  that obtains the pressing start position calculates the position of the cursor (S 303 ). 
     Since the operations until the object determining unit determines an object are identical to those according to Embodiment 1, the description thereof is omitted herein. 
     When determining not to perform the misclick correction (No at S 301 ), the misclick correction control unit  17  outputs misclick stop information to the object selection detecting unit  14 . 
     Upon receipt of the misclick stop information, the object selection detecting unit  14  outputs the ID number of the selected object to the object determining unit  15 . 
     Specifically, upon receipt of the pressing information from the switch  3  and the misclick stop information from the misclick correction control unit  17 , the object selection detecting unit  14  outputs the ID number of the object  12 ( b ) currently selected, to the object determining unit  15 . 
     Since the operation of the object determining unit  15  (S 221 ) and the operation of the object display control unit  13  (S 223 ) are identical to those according to Embodiment 1, the description thereof is omitted herein. 
     According to Embodiment 2, the misclick correction control unit  17  determines whether or not it is highly possible that objects selected before and after performing the misclick correction for changing the cursor position are identical to each other, using the current cursor position on the GUI screen  7  and the object placement information of the object currently selected by the user (that is, overlapped by the cursor  9 ). 
     As a result, when it is highly possible that the objects are identical to each other, the information input device  200  does not perform the misclick correction. 
     In other words, as  FIG. 2  according to Embodiment 1, when the user turned ON the switch  3 , the pressing start position estimating unit  16  does not always perform the misclick correction, and instead, performs it only when it is highly possible that the user cannot determine a target object because of the misclick, that is, it is highly possible that an erroneous operation is performed, according to Embodiment 2. 
     Thus, Embodiment 2 can improve a response speed of a whole input operation more than that according to Embodiment 1. In particular, when the size of an object on the GUI screen  7  is sufficiently larger than the maximum displacement width caused by the misclick, it is less likely that the erroneous operation is performed. Thus, the response speed of a whole input operation can be more improved than that according to Embodiment 1. 
     The misclick correction control unit  17  according to Embodiment 2 may determine whether or not misclick correction is to be performed, based on not only the object placement information of the object detected by the object selection detecting unit  14  and the position of the cursor  9  obtained from the cursor position calculating unit  8 , but also the first object detected by the object selection detecting unit  14  and at least one second object closer to the first object. 
     Next, Modification according to Embodiment 2 will describe the misclick correction control unit  17  that determines whether or not misclick correction is to be performed using the object placement information of the object closer to the detected object, with reference to  FIG. 11 . 
     (Modification of Embodiment 2) 
       FIG. 11  illustrates the GUI screen  7  according to Modification. 
     As illustrated in  FIG. 11 , the object  12 ( b ) is detected by the object selection detecting unit  14 , and the objects  12 ( a ) and  12 ( c ) are closer to the object  12 ( b ). 
     Here, the misclick correction control unit  17  reads the object placement information of each of the objects  12 ( a ) to  12 ( c ) from the object placement storage unit  11 , and determines gaps G(ab) and G(bc) in layout between the objects  12 ( a ) and  12 ( b ) and between the objects  12 ( b ) and  12 ( c ). Here, the object  12 ( b ) is overlapped by the cursor  9  and is detected by the object selection detecting unit  14 . 
     As described above, the misclick correction control unit  17  determines whether or not the misclick correction is to be performed using Expression 6. Here, the misclick correction control unit  17  changes the maximum displacement width B of the position of the cursor subject to the misclick by the user&#39;s finger, according to the gaps G(ab) and G(bc) in layout, not according to a predetermined fixed value. 
     Specifically, the misclick correction control unit  17  compares each of the gaps G(ab) and G(bc) with predetermined two thresholds Gs and Gb, where Gs&lt;Gb. 
     In other words, when the gaps G(ab) and G(bc) are smaller than the threshold Gs, an erroneous operation caused by misclick is more frequently performed. Thus, the misclick correction control unit  17  sets the maximum displacement width B to be smaller by a predetermined value than the normal case. As a result, the misclick correction control unit  17  determines to perform the misclick correction more frequently. 
     Furthermore, when the gaps G(ab) and G(bc) are larger than the threshold Gb, an erroneous operation caused by misclick is less frequently performed. Thus, the misclick correction control unit  17  sets the maximum displacement width B to be larger by a predetermined value than the normal case. As a result, the misclick correction control unit  17  determines to perform the misclick correction less frequently. 
     As such, the misclick correction control unit  17  dynamically changes the threshold for determining whether or not the misclick correction is to be performed, based on a placement relationship between an object selected by the user and an object closer to the selected object in addition to the current cursor position and the object placement information of the selected object on the GUI screen  7 . Thus, the information input device with a superior response speed and less erroneous operation caused by the misclick can be provided. 
     The information input device  200  including the misclick correction control unit  17  according to Embodiment 2 and Modification are described hereinbefore. 
     The information input device  200  prevents the misclick by estimating a pressing start position by the user (position of the finger on the touch sensor  2  at which the user probably started to press the clickable touch sensor  1 ). 
     Next, an information input device  200  including an object lock control unit  18  according to Embodiment 3 in the present invention will be described. The object lock control unit  18  prevents the user from selecting an object other than the object detected by the object selection detecting unit  14 . 
     Embodiment 3 
       FIG. 12  is a block diagram of the information input device  200  according to Embodiment 3 in the present invention. In  FIG. 12 , the same constituent elements as those in  FIG. 2  according to Embodiment 1 are denoted by the same reference numerals, and the detailed description thereof is omitted. 
     As illustrated in  FIG. 12 , the information input device  200  according to Embodiment 3 includes a clickable touch sensor  1 , a touch information detecting unit  4 , a touch information sequence storage unit  5 , a cursor position calculating unit  8 , a cursor display control unit  10 , an object placement storage unit  11 , an object display control unit  13 , an object selection detecting unit  14 , an object determining unit  15 , and the object lock control unit  18 . 
     The difference between  FIG. 12  according to Embodiment 3 and  FIG. 2  according to Embodiment 1 is by including the object lock control unit  18  instead of the pressing start position estimating unit  16 . The object lock control unit  18  will be described hereinafter. 
     The object lock control unit  18  determines whether or not to prevent the user from selecting an object other than the object detected by the object selection detecting unit  14 , based on the touch information item stored in the touch information sequence storage unit  5 . 
     According to Embodiment 3, a process of preventing the user from selecting an object other than the object detected by the object selection detecting unit  14  even when the user&#39;s finger moves on the touch sensor  2  is called a process of locking the object (object locking process). 
       FIG. 13  is a block diagram specific to the object lock control unit  18  according to Embodiment 3. 
     As illustrated in  FIG. 13 , the object lock control unit  18  includes an object lock determining unit  40  and an object lock determination process control unit  41 . 
     The object lock determining unit  40  determines whether or not to prevent the user from selecting an object other than the object detected by the object selection detecting unit  14 , based on the touch information item stored in the touch information sequence storage unit  5 . 
     The object lock determination process control unit  41  determines whether or not to perform an object lock determination process, based on the object placement information of the object detected by the object selection detecting unit  14  and the position of the cursor obtained from the cursor position calculating unit  8 . 
     Furthermore, the object lock determining unit  40  includes a movement amount calculating unit  21  and an object lock information generating unit  42 . 
     The movement amount calculating unit  21  is identical to that included in the pressing start time estimating unit  20  according to Embodiment 1. 
     The object lock information generating unit  42  determines whether or not to prevent the user from selecting an object other than the object detected by the object selection detecting unit  14  based on at least an amount of movement obtained from the movement amount calculating unit  21 , and generates the object lock information according to a result of the determination. 
     Specifically, the object lock information is object lock start information for notifying the object selection detecting unit  14  and the object display control unit  13  of starting to lock an object, and is object lock stop information for notifying the object selection detecting unit  14  and the object display control unit  13  of releasing locking of the object. 
       FIG. 14  illustrates an external view of a GUI screen according to Embodiment 3. 
     The specific operations performed by the object lock control unit  18  will be described with reference to  FIGS. 13 and 14 . 
     First, upon receipt of an ID number of the object  12 ( b ) currently selected by the user from the object selection detecting unit  14 , the object lock determination process control unit  41  obtains the object placement information of the object  12 ( b ) on the GUI screen  7 , from the object placement storage unit  11 . 
     Furthermore, the object lock determination process control unit  41  obtains the current position of the cursor  9  on the GUI screen  7 , from the cursor position calculating unit  8 . 
     Then, the object lock determination process control unit  41  determines whether or not to cause the object lock determining unit  40  to perform an object lock determination process, using the object placement information of the object  12 ( b ) and the position of the cursor  9 . 
     Here, a method for determining whether or not the object lock determination process control unit  41  performs the object lock determination process will be described. 
     Even when the cursor position moves due to the misclick in pressing the touch sensor  2  with the user&#39;s finger, the object lock determination process control unit  41  determines whether or not to perform the object lock determination process, based on whether or not it is highly possible that the object detected by the object selection detecting unit  14  based on the position of the cursor before the movement by the misclick is identical to the object detected by the same based on the position of the cursor after the movement by the misclick. 
     In other words, the object lock determination process control unit  41  determines not to perform the object lock determination process when it is highly possible that the objects before and after the misclick are identical to each other, and otherwise, determines to perform the object lock determination process. 
     More specifically, the object lock determination process control unit  41  has only to define the maximum displacement width of the position of the cursor subject to misclick of the user&#39;s finger, and, even when the objects to be selected before and after moving the current cursor position by the maximum displacement width are identical to each other, determine not to perform the object lock determination process. 
     In other words, assume that on the GUI screen  7 , (X, Y) denotes the current cursor position, (Rx, Ry, W, H) denotes the object placement information of the selected object  12 ( b ) where Rx and Ry denote the lower left coordinate position of the object  12 ( b ), and W and H denote the width and height of the object  12 ( b ), respectively, and B denotes the maximum displacement width of the user&#39;s finger. In the case where the cursor position (X, Y) satisfies the following Expression 7, the object lock determination process control unit  41  determines not to perform the object lock determination process.
 
[Math 7]
 
( Rx&lt;X−B ),( X+B&lt;Rx+W ),( Ry&lt;Y−B ), and ( Y+B&lt;Ry−H )  (Expression 7)
 
     Here, the maximum displacement widths B for vertical and horizontal misclick are not set to a fixed value, and may be set to different values. 
     The method for determining whether or not the object lock determination process control unit  41  performs the object lock determination process is described hereinbefore. 
     When the object lock determination process control unit  41  determines to perform the object lock determination process, the object lock determining unit  40  determines whether or not to lock the object  12 ( b ). 
     Thus, the operations performed by the object lock determining unit  40  will be described in detail next. 
     First, the movement amount calculating unit  21  obtains, from the touch information sequence storage unit  5 , at least one touch information item for a predetermined period from the time previous to the time at which the object selection detecting unit  14  provides the ID number of the object. 
     Next, the movement amount calculating unit  21  determines at least one of types of amounts of movement, such as a movement distance, a movement speed, and a movement acceleration of the user&#39;s finger, using the touch positions and the touch times that are included in the obtained touch information item. 
     Next, the object lock information generating unit  42  determines, using the amount of movement calculated by the movement amount calculating unit  21  (at least one of the movement distance, the movement speed, and the movement acceleration), whether or not the user&#39;s finger is in a stop state, that is, the cursor  9  stopped on the object  12 ( b ) in the GUI screen  7 . 
     When the object lock information generating unit  42  determines that the user&#39;s finger is in the stop state and the object  12 ( b ) detected by the object selection detecting unit  14  is not locked, the object lock information generating unit  42  estimates that the user pressed the touch sensor  2  with the finger to determine the object  12 ( b ). 
     As a result, the object lock information generating unit  42  outputs the object lock start information to the object selection detecting unit  14 . 
     Conversely, when the object lock information generating unit  42  determines that the user&#39;s finger is not in the stop state and the object  12 ( b ) detected by the object selection detecting unit  14  is locked, the object lock information generating unit  42  estimates that the user moved the finger on the touch sensor  2  for selecting the other objects, and outputs the object lock stop information to the object selection detecting unit  14 . 
     The cases where it is determined that the user&#39;s finger is not in the stop state include not only the case where the user&#39;s finger moved on the touch sensor  2  but also the case where the user&#39;s finger was detached from the touch sensor  2 . 
     Furthermore, when the user turned ON the switch  3  (that is, determined the object  12 ( b )), the object lock information generating unit  42  outputs the object lock stop information to the object selection detecting unit  14 . 
     As such, the locked object is released when the user moves the finger on the touch sensor  2 , detaches the finger from the touch sensor  2 , or turns ON the switch  3 . 
     Next, assuming the amount of movement calculated by the movement amount calculating unit  21  as the movement speed, the operations performed by the object lock information generating unit  42  will be described more specifically. 
     Assuming that T denotes a time at which the object selection detecting unit  14  provides the ID number of the object  12 ( b ) to the movement amount calculating unit  21  and (x(t), y(t)) denotes a touch position at a certain time t using X and Y coordinates, the movement amount calculating unit  21  calculates, using Equation 8, a movement speed v(t) (t=T−1, T−2, . . . , T−n) of the finger on “n” clickable touch sensors  1  for a predetermined period before the time T.
 
[Math 8]
 
 v ( t )=√{square root over (( x ( t )− x ( t− 1)) 2 +( y ( t )− y ( t− 1)) 2 )}{square root over (( x ( t )− x ( t− 1)) 2 +( y ( t )− y ( t− 1)) 2 )}{square root over (( x ( t )− x ( t− 1)) 2 +( y ( t )− y ( t− 1)) 2 )}{square root over (( x ( t )− x ( t− 1)) 2 +( y ( t )− y ( t− 1)) 2 )}  (Equation 8)
 
     The object lock information generating unit  42  determines that the user&#39;s finger is in the stop state on the touch sensor  2 , when the movement speed v(t) is continuously lower than or equal to a predetermined value for a predetermined period n′. 
     More specifically, assuming that Vs denotes a threshold of the movement speed v(t) at which the finger stopped, the object lock information generating unit  42  determines that the user&#39;s finger is in the stop state when t that satisfies v(t)≦Vs from among the “n” movement speeds v(t) calculated by Equation 8 continues for the predetermined period n′. 
     When at least two types of amounts of movement of the finger are smaller than or equal to a predetermined value for a fixed period, the object lock information generating unit  42  may determine that the finger is in the stop state, as the other methods for determining the stop state of the finger. 
       FIG. 15  is a flowchart of processes performed by the information input device  200  according to Embodiment 3. 
     Here,  FIG. 15  will describe a series of operations in which the user selects and determines (executes), using the clickable touch sensor  1 , the target object  12 ( b ) from among the objects  12 ( a ) to  12 ( c ) placed on the GUI screen  7  displayed by the screen display unit  6  as a specific example, as according to Embodiments 1 and 2. 
     Furthermore, the configuration of Embodiment 3 additionally includes the object lock control unit  18  instead of the pressing start position estimating unit  16  in  FIG. 2  according to Embodiment 1, and the other constituent elements perform the same operations as according to Embodiment 1. 
     Specifically, in the series of operations in which the user selects (i.e. places the cursor  9  on the target object  12 ( b ) in the GUI screen  7 ) and determines (presses the clickable touch sensor  1 ), using the clickable touch sensor  1 , the target object  12 ( b ) from among the objects  12 ( a ) to  12 ( c ) placed on the GUI screen  7  displayed by the screen display unit  6 , operations performed by the constituent elements until the user selects the target object  12 ( b ) are identical to those according to Embodiment 1. 
     Thus, the processes of the object lock determining unit  40  after the object lock determination process control unit  41  determines to lock an object will be described hereinafter. 
     Upon receipt of the ID number of the object  12 ( b ) from the object selection detecting unit  14 , the object lock determining unit  40  determines whether or not to prevent the user from selecting an object other than the object  12 ( b ) based on the touch information item stored in the touch information sequence storage unit  5 , that is, to lock the object  12 ( b ) (S 401  in  FIG. 15 ). 
     When determining to lock the object, the object lock determining unit  40  outputs the object lock start information to the object selection detecting unit  14  and the object display control unit  13  (Yes at S 401 ). 
     Upon receipt of the object lock start information from the object lock determining unit  40 , the object selection detecting unit  14  locks the object  12 ( b ) that is an object currently selected by the user. 
     Furthermore, upon receipt of the object lock start information from the object lock determining unit  40 , the object display control unit  13  displays the object  12 ( b ) that is an object corresponding to the ID number obtained from the object selection detecting unit  14 , for example, presents that the object  12 ( b ) has been locked to the user by changing the size and color, etc of the object (S 403 ). 
     Furthermore, with the touch sensor  2  pressed down and the switch  3  turned ON to determine the object  12 ( b ) selected by the user (Yes at S 405 ), the switch  3  outputs the pressing information to the object selection detecting unit  14  and the object lock determining unit  40 . 
     As in  FIG. 2  according to Embodiment 1, upon receipt of the pressing information from the switch  3 , the object selection detecting unit  14  outputs the ID number of the object  12 ( b ) detected (that is, overlapped by the cursor  9 ), to the object determining unit  15 . 
     Upon receipt of the ID number of the object  12 ( b ) from the object selection detecting unit  14 , assuming that the user determines the object  12 ( b ), the object determining unit  15  outputs the ID number to the object display control unit  13  and performs a determination process corresponding to the object  12 ( b ) (S 407 ). 
     Upon receipt of the ID number of the object  12 ( b ) from the object determining unit  15 , the object display control unit  13  displays the object  12 ( b ) on the GUI screen  7 , for example, presents determination of the object  12 ( b ) to the user by changing the size and color of the object (S 409 ). 
     Furthermore, upon receipt of the pressing information from the switch  3 , the object lock determining unit  40  outputs the object lock stop information to the object selection detecting unit  14  (S 411 ). 
     Upon receipt of the object lock stop information from the object lock determining unit  40 , the object selection detecting unit  14  releases (stops) current locking of the object  12 ( b ) so that the user can select objects other than the object  12 ( b ) again. 
     Here, the object lock determining unit  40  can output the object lock stop information after outputting the object lock start information. 
     Similarly, the object lock determining unit  40  can output the object lock start information in an initial state in which none of the objects is selected, or after outputting the object lock stop information. 
     In other words, the process of outputting the object lock start information and the object lock stop information is a toggle process. 
     As described above, the information input device  200  according to Embodiment 3 detects that the user&#39;s finger is to press the touch sensor  2  and locks an object selected by the user to prevent the user from selecting an object other than the selected object before the user&#39;s finger starts to press the switch  3 . Thus, even when the user&#39;s finger pressed the switch  3  and the finger was slightly displaced with the pressure of the finger, the object selected by the user can be reliably determined, and an erroneous operation caused by the misclick can be reduced. 
     Furthermore, a touch position changing operation can be performed by moving the finger on the touch sensor  2  unless the user completely presses down the switch  3  according to Embodiment 3. The method is different from the conventional information input method for preventing the misclick by detecting an operation of the user who intends to press the switch  3  with pressure of the user&#39;s finger to the touch sensor  3  and invalidating the touch position changing operation by the movement of the user&#39;s finger. 
     In other words, even when the user moves the finger on the touch sensor  2  and somewhat strongly presses the touch sensor  2 , the user can successively input touch positions, that is, continuously move the cursor  9  on the GUI screen  7 . Thus, the operability can be more improved than that of the conventional information input device. 
     Furthermore, although the conventional information input device needs the special touch sensor  101  that can detect the pressure of the user&#39;s finger, the touch sensor  2  that is generally used for detecting a position of a finger can also prevent the misclick according to Embodiment 3. 
     Although the object lock control unit  18  according to Embodiment 3 determines to cause the object lock determining unit  40  to perform the object lock determination process, using the object lock determination process control unit  41 , the object lock determining unit  40  may always perform the object lock determination process without the object lock determination process control unit  41 . 
     Furthermore, although the object lock determination process control unit  41  determines to perform the object lock determination process, using the object placement information of the object detected by the object selection detecting unit  14  and the position of the cursor  9  obtained from the screen display unit  6 , the determination may be further made using object placement information of at least one object closer to the detected object. 
     The determination method will be specifically described as Modification of Embodiment 3. 
     (Modification of Embodiment 3) 
     For example, assume the objects closer to the object  12 ( b ) detected by the object selection detecting unit  14 , to be the objects  12 ( a ) and  12 ( c ) as in the GUI screen  7  illustrated in  FIG. 11 . 
     Here, the object lock determination process control unit  41  reads the object placement information of each of the objects  12 ( a ) to  12 ( c ) from the object placement storage unit  11 , and determines gaps G(ab) and G(bc) in layout between the object  12 ( a ) and the detected object  12 ( b ) and between the objects  12 ( b ) and  12 ( c ). Here, the objects  12 ( a ) and  12 ( c ) are closer to the object  12 ( b ). 
     As described above, the object lock determination process control unit  41  determines to perform the object lock determination process using Expression 7. 
     More specifically, the object lock determination process control unit  41  changes the maximum displacement width B of the cursor position subject to the misclick by the user&#39;s finger, according to the gaps G(ab) and G(bc) in layout, not according to a predetermined fixed value. 
     More specifically, the object lock determination process control unit  41  compares each of the gaps G(ab) and G(bc) with predetermined two thresholds Gs and Gb, where Gs&lt;Gb. 
     In other words, when the gaps G(ab) and G(bc) are smaller than the threshold Gs, an erroneous operation caused by the misclick is more frequently performed. Thus, the misclick correction control unit  17  sets the maximum displacement width B to be smaller than the normal case in order to more frequently perform the object lock determination process. 
     Furthermore, when the gaps G(ab) and G(bc) are larger than the threshold Gb, the erroneous operation caused by the misclick is less frequently performed. Thus, the misclick correction control unit  17  sets the maximum displacement width B to be larger than the normal case in order to less frequently perform the object lock determination process. 
     As such, the misclick correction control unit  17  dynamically changes the threshold to determine whether or not to perform the object lock determination process, based on a placement relationship between an object currently selected by the user and an object closer to the selected object in addition to the cursor position and the object placement information of the selected object. Thus, the information input device with a superior response speed and less erroneous operation caused by the misclick can be provided. 
     Although each of the processing units other than the clickable touch sensor  1  including the touch sensor  2  and the switch  3  and the screen display unit  6  that displays the GUI screen  7  including the cursor  9  and the objects  12 ( a ) to  12 ( c ) is implemented by dedicated hardware according to each of Embodiments, functions similar to those of the processing units may be implemented in a software manner using a computer, instead of the hardware. 
     More specifically, the information input device described Embodiments 1 to 3 and Modifications can be implemented by a computer. 
     As shown by  FIG. 16 , the information input device  200  includes: a computer  34 ; a keyboard  36  and a mouse  38  for instructing the computer  34 ; a display  32  for displaying information such as computational results of the computer  34 ; a Compact Disc-Read only memory (CD-ROM) device  40  for reading programs to be executed by the computer  34 ; and a communication modem (not shown). 
     The programs that are processes performed by the information input device  200  are recorded on a CD-ROM  42 , a computer-readable recording medium, and are read by the CD-ROM device  40 . Alternatively, the programs are read by the communication modem via a computer network  26 . 
       FIG. 17  is a block diagram showing a hardware configuration of a computer system which implements the information input device  200 . The computer  34  includes a Central Processing Unit (CPU)  44 , a Read Only Memory (ROM)  46 , a Random Access Memory (RAM)  48 , a hard disk  50 , a communication modem  52 , and a bus  54 . 
     The CPU  44  executes programs read via the CD-ROM device  40  or the communication modem  52 . The ROM  46  stores programs or data necessary for operations performed by the computer  34 . The RAM  48  stores data such as parameters at the time of program execution. The hard disk  50  stores the programs, the data, and so on. The communication modem  52  communicates with other computers via the computer network  26 . The bus  54  connects the CPU  44 , the ROM  46 , the RAM  48 , the hard disk  50 , the communication modem  52 , the display  32 , the keyboard  36 , the mouse  38 , and the CD-ROM device  40  to each other. 
     Moreover, part or all of the constituent elements included in each of the above devices may be included in one system Large Scale Integration (LSI). The system LSI is a super-multifunctional LSI manufactured by integrating components on one chip and is, specifically, a computer system including a micro processing unit, a ROM, and a RAM. The RAM stores a computer program. The micro processing unit operates according to the computer program, so that the system LSI fulfills its function. 
     Furthermore, part or all of the constituent elements included in each of the above devices may be included in an IC card removable from each of the devices or in a stand alone module. The IC card or the module is the computer system including the micro processing unit, the ROM, and the RAM. The IC card or the module may include the super-multifunctional LSI. The micro processing unit operates according to the computer program, so that the IC card or the module fulfills its function. The IC card or the module may have tamper-resistance. 
     Moreover, the present invention may be any of the above methods. Furthermore, the present invention may be a computer program which causes a computer to execute these methods, and a digital signal which is composed of the computer program. 
     Moreover, in the present invention, the computer program or the digital signal may be recorded on a computer-readable recording medium such as a flexible disk, a hard disk, a CD-ROM, an MO, a DVD, a DVD-ROM, a DVD-RAM, a BD (Blu-ray Disc®), a USB memory, a memory card such as a SD card, and a semiconductor memory. In addition, the digital signal may be recorded on these recording media. 
     Furthermore, in the present invention, the computer program or the digital signal may be transmitted via an electronic communication line, a wireless or wired communication line, a network represented by the Internet, data broadcasting, and the like. 
     Moreover, the present invention may be a computer system including a micro processing unit and a memory. The memory may store the computer program, and the micro processing unit may operate according to the computer program. 
     Furthermore, the present invention may execute the computer program or the digital signal in another independent computer system by recording the computer program or the digital signal on the recording medium and transmitting the recorded computer program or digital signal or by transmitting the computer program or the digital signal via the network and the like. 
     Furthermore, Embodiments and Modifications above may be combined with each other. 
     It should be considered that Embodiments disclosed herein are exemplary in all respects and not restrictive at all. It is intended that the scope of the present invention is indicated by not the above description of Embodiments but Claims, and includes any change within Claims, the meanings of equivalents, and the scope of the equivalents. 
     INDUSTRIAL APPLICABILITY 
     The present invention relates to, for example, an information input device that operates a GUI screen of an electronic device, and in particular to an information input device including a clickable touch sensor that operates the GUI screen using a touch sensor. 
     REFERENCE SIGNS LIST 
     
         
           1  Clickable touch sensor 
           2  Touch sensor 
           3  Switch 
           4  Touch information detecting unit 
           5  Touch information sequence storage unit 
           6  Screen display unit 
           7  GUI screen 
           8  Cursor position calculating unit 
           9  Cursor 
           10  Cursor display control unit 
           11  Object placement storage unit 
           12 ( a ) to  12 ( c ) Object 
           13  Object display control unit 
           14  Object selection detecting unit 
           15  Object determining unit 
           16  Pressing start position estimating unit 
           17  Misclick correction control unit 
           18  Object lock control unit 
           20  Pressing start time estimating unit 
           21  Movement amount calculating unit 
           22  Stop time detecting unit 
           23  Touch position determining unit 
           24  Touch area calculating unit 
           25  Pressed area arrival time detecting unit 
           26  Pressing start time determining unit 
           30  Moving direction calculating unit 
           31  Misclick start time detecting unit 
           40  Object lock determining unit 
           41  Object lock determination process control unit 
           42  Object lock information generating unit 
           100  Clickable touch sensor 
           101  Touch sensor 
           102  Switch 
           103  Touch information detecting unit 
           105  GUI screen 
           106  Cursor position calculating unit 
           107  Cursor 
           108  Cursor display control unit 
           109  Object placement storage unit 
           110 ( a ) to  110 ( c ) Object 
           111  Object display control unit 
           112  Object selection detecting unit 
           113  Object determining unit 
           114  Cursor movement invalidating unit 
           200  Information input device 
           300  Screen display device 
           400  Screen control unit 
           500  Screen display device