Abstract:
Disclosed is an electronic device that makes it easy to input desired characters using a directional key. Also disclosed is a display control method for an electronic device. The disclosed electronic device is provided with a display unit ( 21 ), a user input unit ( 11 ) that can specify a plurality of directions, and a control unit ( 45 ). If one of the plurality of directions is specified via the user input unit ( 11 ) while characters and numbers are being displayed on the display unit ( 21 ), the control unit selects different characters and different numbers for changing the characters and/or numbers displayed on the display unit ( 21 ) to other characters and numbers. The control unit then has the display unit ( 21 ) display the selected other characters and numbers.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS: 
     This application is the National Stage of International Application No. PCT/JP2011/053176, filed Feb. 15, 2011, which claims the benefit of Japanese Application Nos. 2010-030737, filed Feb. 15, 2010, and 2010-074603, filed Mar. 29, 2010, the entire contents of all of which are incorporated by reference herein. 
     FIELD OF THE INVENTION 
     The present invention relates to an electronic device capable of inputting characters. 
     BACKGROUND OF THE INVENTION 
     Some electronic devices such as mobile telephone devices include: an operation unit with input keys for inputting non-numeric characters and numeric characters; and a display unit for displaying the non-numeric characters and the numeric characters that are input by operating the input keys. With such electronic devices, in a case in which the input key is operated in a state where a standard screen is displayed on the display unit, a non-numeric character and a numeric character assigned to the input key thus operated can be concurrently input (see Patent Document 1). The standard screen is a screen that is displayed in a standby state for an operation of the input keys or the like, in which other applications are not running. The standard screen is also referred to as an idle screen, an initial screen, a wall paper screen or a desktop screen. 
     Among electronic devices, for example, a gaming machine does not include a full keyboard that is provided to a personal computer and the like, and a 10-key keyboard that is provided to a mobile telephone device and the like. In a case of such an electronic device without a 10-key keyboard and a full keyboard, a character is input by using a direction designation key such as a cross key (see Patent Document 2). 
     Patent Document 1: Japanese Unexamined Patent Application, Publication No. 2009-32209 
     Patent Document 2: Japanese Unexamined Patent Application, Publication No. 2003-108298 
     SUMMARY OF THE INVENTION 
     Problems to be Solved by the Invention 
     With an electronic device disclosed in Patent Document 1, by operating an input key for inputting a non-numeric character and a numeric character, the non-numeric character and the numeric character assigned to the input key thus operated are input. Therefore, with the aforementioned electronic device, even in a case of operating a key (for example, a direction designation key for designating a direction) other than the input keys for inputting non-numeric characters and numeric characters, a non-numeric character and a numeric character cannot be input. 
     With an electronic device disclosed in Patent Document 2, in a case of inputting characters by using direction designation keys, since the number of such keys for inputting characters is limited, a problem as follows has been suffered. For example, in a case in which a user of the aforementioned electronic device selects a character from a character palette for displaying characters that can be input, and inputs a desired character by using a conversion candidate or a predictive candidate for the character, the user had to separately use the inputting using the character palette with the direction designation keys, and the inputting using the predictive candidate or the conversion candidate; therefore, the operation has been complicated. 
     An object of the invention is to provide an electronic device capable of easily inputting at least a desired character, based on an operation of direction designation keys. 
     Means for Solving the Problems 
     The electronic device according to the present invention includes: a display unit; an operation unit capable of designating a plurality of directions; and a control unit. In a state where a non-numeric character and a numeric character are displayed on the display unit, in a case in which any direction is designated by the operation unit, the control unit selects an other non-numeric character and an other numeric character for changing at least one of the non-numeric character and the numeric character displayed on the display unit to the other non-numeric character and the other numeric character, respectively, and causes the display unit to display the other non-numeric character and the other numeric character thus selected. 
     It is preferable for the operation unit to be capable of designating a first direction, a second direction that is a direction opposite to the first direction, a third direction that is a direction transverse to the first direction, and a fourth direction that is a direction opposite to the third direction. In a state where the non-numeric character and the numeric character are displayed on the display unit, in a case in which the first direction or the second direction is designated by the operation unit, it is preferable for the control unit to select an other non-numeric character and an other numeric character for changing the non-numeric character and the numeric character displayed on the display unit to the other non-numeric character and the other numeric character, respectively, and to cause the display unit to display the other non-numeric character and the other numeric character thus selected. In a state where the non-numeric character and the numeric character are displayed on the display unit, in a case in which the third direction or the fourth direction is designated by the operation unit, it is preferable for the control unit to select an other non-numeric character for changing the non-numeric character displayed on the display unit to the other non-numeric character, to cause the display unit to display the other non-numeric character thus selected, and to maintain displaying of the numeric character as displayed on the display unit. 
     In a case in which the non-numeric character and the numeric character are displayed on the display unit, it is preferable for the control unit to cause the display unit to display a non-numeric character input area for displaying the non-numeric character, and a numeric character input area for displaying the numeric character, and in a case in which the third direction or the fourth direction is designated by the operation unit, it is preferable for the control unit to maintain displaying of the non-numeric character input area for displaying the non-numeric character as well as the non-numeric character thus displayed, and to cancel displaying of the numeric character input area for displaying the numeric character as well as the numeric character thus displayed. 
     It is preferable for a non-numeric character and a numeric character to be associated with each direction that can be designated by the operation unit, and in a case in which any direction is designated by the operation unit, it is preferable for the control unit to cause the display unit to display at least one of a non-numeric character and a numeric character associated with the direction thus designated. 
     It is preferable for a predetermined function to be assigned to each direction that can be designated by the operation unit. In a case in which any direction is designated by the operation unit, it is preferable for the control unit to cause the display unit to perform displaying based on a predetermined function assigned to the direction thus designated, and to display at least one of a non-numeric character and a numeric character associated with the direction thus designated. In a state where the displaying based on the predetermined function is performed, and at least one of the non-numeric character and the numeric character is displayed on the display unit, in a case in which any direction is further designated by the operation unit, it is preferable for the control unit to select an other non-numeric character and an other numeric character for changing at least one of the non-numeric character and the numeric character displayed on the display unit to the other non-numeric character and the other numeric character, respectively, and to cause the display unit to display the other non-numeric character and the other numeric character thus selected, or to select a display item based on the predetermined function. 
     In a state where a standard screen is displayed on the display unit, in a case in which any direction is designated by the operation unit, it is preferable for the control unit to cause the display unit to display a non-numeric character and a numeric character associated with the direction thus designated, and a non-numeric character palette composed of a plurality of non-numeric characters used for changing a non-numeric character to an other non-numeric character. 
     It is preferable for a non-numeric character, a numeric character and a predetermined function to be associated with each direction that can be designated by the operation unit. In a state where a standard screen is displayed on the display unit, in a case in which any direction is designated by the operation unit, it is preferable for the control unit to cause the display unit to perform displaying based on a non-numeric character, a numeric character and a predetermined function associated with the direction thus designated. 
     The electronic device according to the present invention includes: an operation unit capable of designating a plurality of directions, and performing a determination operation; a display unit that displays: a first area for displaying a plurality of characters that can be selected as input characters; a second area for displaying a predictive candidate or a conversion candidate for the characters thus input; and a third area that is adjacent to the first area and the second area; and a control unit. In a state where a character displayed in the first area is selected, in a case in which there is no character in a direction designated by operating the operation unit, the control unit selects the third area. In a state where the third area is selected, in a case in which a determination operation is performed by the operation unit, the control unit selects the second area or the conversion candidate or the prediction candidate displayed in the second area, and in a case in which any direction is designated by the operation unit, the control unit selects the first area or the character displayed in the first area. 
     The electronic device according to the present invention includes: an operation unit capable of designating a plurality of directions, and performing a determination operation; a display unit that displays: a first area for displaying a plurality of characters that can be selected as input characters; a second area for displaying a predictive candidate or a conversion candidate for the characters thus input; and a third area that is adjacent to the first area and the second area; and a control unit. In a state where a character displayed in the first area is selected, in a case in which there is no character in a direction designated by operating the operation unit, the control unit selects the third area. In a state where the third area is selected, in a case in which a determination operation is performed by the operation unit, the control unit selects the first area or the character displayed in the first area, and in a case in which any direction is designated by the operation unit, the control unit selects the second area or the conversion candidate or the prediction candidate displayed in the second area. 
     In a state where the conversion candidate or the predictive candidate displayed in the second area is selected, in a case in which there is no conversion candidate or predictive candidate in a direction designated by operating the operation unit, it is preferable for the control unit to select the third area. 
     It is preferable for a character palette for displaying characters of a Japanese syllabary based on vowels and consonants to be displayed in the first area. In a case in which the character displayed in the first area is selected after selecting the third area, it is preferable for the control unit to select a character, which has a vowel or consonant identical to that of a character selected in the first area immediately before selecting the third area, and which is different from the character that was selected. 
     It is preferable for a character to be associated with each direction that can be designated by the operation unit. In a state where a standard screen is displayed on the display unit, in a case in which any direction is designated by the operation unit, it is preferable for the control unit to cause the display unit to display a character associated with the direction thus designated. 
     Effects of The Invention 
     According to the invention, a desired character can be easily input, based on an operation of direction designation keys. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view showing an appearance of a mobile telephone device according to a first embodiment of an electronic device; 
         FIG. 2  is a functional block diagram showing functions of the mobile telephone device according to the first embodiment; 
         FIG. 3  is a first diagram for illustrating a non-numeric character palette and a numeric character palette; 
         FIG. 4  is a second diagram for illustrating the non-numeric character palette and the numeric character palette; 
         FIG. 5  is a flow chart for illustrating a first operation of the mobile telephone device; 
         FIG. 6  is a diagram for illustrating screen transition in the first operation of the mobile telephone device; 
         FIG. 7  is a flow chart for illustrating a second operation of the mobile telephone device; 
         FIG. 8  is a flow chart for illustrating a third operation of the mobile telephone device; 
         FIG. 9  is a first diagram for illustrating screen transition in a fourth operation of the mobile telephone device; 
         FIG. 10  is a second diagram for illustrating screen transition in the fourth operation of the mobile telephone device; 
         FIG. 11  is a flow chart for illustrating a fifth operation of the mobile telephone device; 
         FIG. 12  is a diagram for illustrating screen transition in the fifth operation of the mobile telephone device; 
         FIG. 13  is a perspective view showing an appearance of a mobile telephone device according to a second embodiment of the electronic device of the present invention; 
         FIG. 14  is a functional block diagram showing a schematic configuration of functions of the mobile telephone device according to the second embodiment; 
         FIG. 15  is a diagram showing an example of a first area, a second area, a third area and a character input area, which are displayed on a display unit of the mobile telephone device; 
         FIG. 16  is a diagram for illustrating screen transition in a sixth operation according to the present invention; and 
         FIG. 17  is a diagram for illustrating screen transition in a seventh operation according to the present invention. 
     
    
    
     EXPLANATION OF REFERENCE NUMERALS 
     1 mobile telephone device (electronic device) 
       11  operation unit 
       11   a  direction designation key 
       11   b  function activation key 
       11   c  determination key 
       12  microphone 
       21  display unit 
       22  speaker 
       23  driver IC 
       40  main antenna 
       41  RF circuit unit 
       42  image processing unit 
       43  sound processing unit 
       44  memory 
       45  control unit 
       50  cursor 
       100  first area 
       200  second area 
       300  third area 
       400  character input area 
     DETAILED DESCRIPTION OF THE INVENTION 
     Descriptions are hereinafter provided for the best mode for carrying out the present invention with reference to the drawings. 
     First Embodiment 
     First of all, with reference to  FIG. 1 , descriptions are provided for a basic structure of a mobile telephone device  1  according to a first embodiment of the electronic device of the present invention.  FIG. 1  is a perspective view showing an appearance of the mobile telephone device  1  according to the first embodiment of the electronic device. 
     The mobile telephone device  1  is a mobile telephone device of a straight type. An external shape of the mobile telephone device  1  is mainly configured with: a case  2 ; a removable member  3  that is removably attached to the case  2 ; and a strap  4  that is connected to the removable member  3 . The mobile telephone device  1  has a security alarm function, in addition to a telephone call function. The security alarm function is a function to draw attention of people around a user by operating the mobile telephone device  1  to generate sound at full blast, in a case in which the user sensed danger. 
     An operation unit  11 , a display unit  21 , a microphone  12  and a speaker  22  are disposed on a front face  2   a  of the case  2 . 
     The operation unit  11  includes a plurality of direction designation keys  11   a  (direction designating means) for designating distinct directions, and a function activation key  11   b  for activating a predetermined function. Here, even in a case in which the plurality of direction designation keys  11   a  are physically composed of a single key as shown in  FIG. 1 , such a key is assumed to be a plurality of direction designation keys as long as different functions are assigned to upper, right, lower and left directions, respectively. More specifically, such a key may be capable of designating a plurality of directions, and may be a joystick, a track ball, or other pointing devices. Detection through a capacitive sensor or an infrared sensor may be employed to enable designation of a plurality of directions. 
     In the present invention, the direction designation keys  11   a  of the operation unit  11  perform not only a direction designation operation and a scroll operation in upper, lower, left and right directions, but also an input operation of symbols including numeric characters, non-numeric characters, alphabetic characters and the like. Here, the present invention assumes that a numeric character includes not only a single numeric character but also a numeric character string, a character includes not only a single character but also a character string, an alphabetic character includes not only a single alphabetic character but also an alphabetic character string, and a symbol includes not only a single symbol but also a symbol string. The direction designation keys  11   a  include an upper key  111  capable of designating the upper direction, a lower key  112  capable of designating the lower direction, a right key  113  capable of designating the right direction, and a left key  114  capable of designating the left direction. 
     Characters include non-numeric characters other than numeric characters, such as, for example, hiragana characters, katakana characters, alphabetic characters, symbols and the like. 
     The display unit  21  is composed of a liquid crystal display, an organic EL (electroluminescence) display or the like. The microphone  12  inputs sound produced by the user of the mobile telephone device  1  during a telephone call. The speaker  22  outputs sound of the other party of a telephone call when using the mobile telephone device  1 . 
     The mobile telephone device is not limited to the mobile telephone device  1  of the straight type described above. In other words, the mobile telephone device may be of: a slider type in which one case slides to one direction from a state in which the operation unit side case and the display unit side case are mutually superimposed; a rotating type in which one case is rotated around an axis line along the superimposing direction; a type in which the display unit side case and the operation unit side case are connected via a 2-axis hinge; or a flip type in which the display unit side case and the operation unit side case are connected via a hinge mechanism. 
     Next, descriptions are provided for a functional configuration of the mobile telephone device  1 .  FIG. 2  is a functional block diagram showing functions of the mobile telephone device  1 . The mobile telephone device  1  includes: the operation unit  11 , the microphone  12 , a main antenna  40 , an RF circuit unit  41 , an image processing unit  42 , a sound processing unit  43 , memory  44 , the control unit  45 , the display unit  21 , the speaker  22 , and a driver IC  23 . The configurations of the operation unit  11 , the display unit  21 , the microphone  12  and the speaker  22  are as described above. 
     The main antenna  40  is configured to communicate with external devices such as base stations via a predetermined usable frequency band (for example, 800 MHz band). Although 800 MHz is set as the predetermined usable frequency band in the present embodiment, other frequency bands can also be used. 
     The RF circuit unit  41  executes demodulation processing on a signal received via the main antenna  40 , and transmits the processed signal to the control unit  45 . The RF circuit unit  41  executes modulation processing on a signal transmitted from the control unit  45 , and transmits the signal to external devices via the main antenna  40 . On the other hand, the RF circuit unit  41  notifies the control unit  45  of the intensity of a signal received via the main antenna  40 . 
     The image processing unit  42  executes predetermined image processing, and outputs the processed image data to the driver IC  23 , in accordance with control by the control unit  45 . When the image data is transmitted from the image processing unit  42 , the driver IC  23  stores the image data in frame memory, and outputs the image data to the display unit  21  at predetermined timing. 
     The sound processing unit  43  executes predetermined sound processing on a signal transmitted from the RF circuit unit  41 , and outputs the processed signal to the speaker  22 , in accordance with control by the control unit  45 . The speaker  22  externally outputs the signal that is transmitted from the sound processing unit  43 . 
     When a signal is input from the microphone  12 , the sound processing unit  43  processes the signal, and outputs the processed signal to the RF circuit unit  41 , in accordance with control by the control unit  45 . The RF circuit unit  41  executes predetermined processing on the signal transmitted from the sound processing unit  43 , and outputs the processed signal to the main antenna  40 . 
     The memory  44  includes, for example, working memory, and is utilized for arithmetic processing by the control unit  45 . The memory  44  stores a plurality of applications as well as various tables and the like that are required by the applications. The memory  44  may also serve as detachable external memory. 
     The control unit  45  controls the entirety of the mobile telephone device  1 , and is configured to employ a central processing unit (CPU) and the like. 
     The mobile telephone device  1  as thus constituted has a function capable of concurrently inputting a non-numeric character and a numeric character, based on an operation of the direction designation keys  11   a.    
     Descriptions are hereinafter provided for a configuration and operations for achieving the aforementioned function according to the mobile telephone device  1 . 
     In a case in which a predetermined operation is performed via the operation unit  11 , the control unit  45  causes the display unit  21  to display a non-numeric character and a numeric character. In a state where a non-numeric character and a numeric character are displayed on the display unit  21 , in a case in which any key of the direction designation keys  11   a  is further operated (in a case in which any direction is designated by the direction designation key  11   a ), the control unit  45  selects an other non-numeric character and an other numeric character for changing at least one of the non-numeric character and the numeric character displayed on the display unit  21  to the other non-numeric character and the other numeric character, respectively, and causes the display unit  21  to display the other non-numeric character and the other numeric character thus selected. Here, the predetermined operation via the operation unit  11  may be an operation of a key for activating a screen for editing non-numeric characters and numeric characters, or may be an operation of any key of the direction designation keys  11   a  as will be described later. 
     More specifically, in a case in which any key of the direction designation keys  11   a  is operated, the control unit  45  causes the display unit  21  to display, for example, a hiragana character “a” and a numeric character “0”. A non-numeric character and a numeric character to be displayed when operating a key are any non-numeric character and any numeric character, or a preset non-numeric character and a preset numeric character. In a state where the hiragana character “a” and the numeric character “0” are displayed on the display unit  21 , in a case in which any key of the direction designation keys  11   a  is further operated, and selection is performed to change at least one of the hiragana character “a” and the numeric character “0” to an other non-numeric character (for example, a hiragana character “i”) and an other numeric character (for example, a numeric character “1”), respectively, the control unit  45  causes the display unit  21  to display the other hiragana character “i” and the other numeric character “1” thus selected. 
     As a result, with the mobile telephone device  1 , in a case in which any key of the direction designation keys  11   a  is operated, the display unit  21  displays a non-numeric character and a numeric character, and in a case in which any key of the direction designation keys  11   a  is further operated, at least one of the non-numeric character and the numeric character displayed on the display unit  21  is changed to an other non-numeric character and an other numeric character, respectively, and the display unit  21  displays the other non-numeric character and the other numeric character; therefore, at least one of a non-numeric character and a numeric character can be input, based on an operation of the direction designation keys  11   a.    
     The direction designation keys  11   a  include: a first key capable of designating a first direction; a second key capable of designating a second direction that is a direction opposite to the first direction; a third key capable of designating a third direction that is a direction transverse to the first direction; and a fourth key capable of designating a fourth direction that is a direction opposite to the third direction. In the present embodiment, the first key is the upper key  111 , and the second key is the lower key  112  (see  FIG. 1 ). In the present embodiment, the third key is the right key  113 , and the fourth key is the left key  114  (see  FIG. 1 ). 
     In this case, in a state where a non-numeric character and a numeric character are displayed on the display unit  21 , in a case in which the upper key  111  or the lower key  112  is operated, the control unit  45  selects an other non-numeric character and an other numeric character for changing the non-numeric character and the numeric character displayed on the display unit  21  to the other non-numeric character and the other numeric character, respectively, and causes the display unit  21  to display the other non-numeric character and the other numeric character thus selected. More specifically, for example, in a state where the hiragana character “a” and the numeric character “0” are displayed on the display unit  21  as a result of operating any key of the direction designation keys  11   a , in a case in which the upper key  111  or the lower key  112  is further operated, the control unit  45  performs selection for changing the hiragana character “a” and the numeric character “0” to an other non-numeric character (for example, a hiragana character “i”) and an other numeric character (for example, a numeric character “1”), respectively, and the control unit  45  causes the display unit  21  to display the other hiragana character “i” and the other numeric character “1” thus selected. 
     On the other hand, in a state where a non-numeric character and a numeric character are displayed on the display unit  21 , in a case in which the right key  113  or the left key  114  is operated, the control unit  45  selects an other non-numeric character for changing the non-numeric character displayed on the display unit  21  to the other non-numeric character, causes the display unit  21  to display the other non-numeric character thus selected, and maintains the displaying of the numeric character as displayed on the display unit  21 . More specifically, for example, in a state where the hiragana character “a” and the numeric character “0” are displayed on the display unit  21  as a result of operating any key of the direction designation keys  11   a , in a case in which the right key  113  or the left key  114  is further operated, the control unit  45  performs selection for changing the hiragana character “a” to an other non-numeric character (for example, a hiragana character “ka”), and the control unit  45  causes the display unit  21  to display the other hiragana character “ka” thus selected. The control unit  45  does not change the numeric character “0” displayed on the display unit  21  to an other numeric character, and causes the display unit  21  to keep displaying the numeric character “0”. 
     As a result, with the mobile telephone device  1 , in a state where a non-numeric character and a numeric character are displayed on the display unit  21 , in a case in which the upper key  111  or the lower key  112  is operated, the non-numeric character and the numeric character displayed on the display unit  21  are changed to an other non-numeric character and an other numeric character, respectively; on the other hand, in a case in which the right key  113  or the left key  114  is operated, only the non-numeric character that is input and displayed on the display unit  21  is changed to an other non-numeric character; therefore, at least one of the non-numeric character and the numeric character can be input, based on an operation of the direction designation keys  11   a.    
     A non-numeric character and a numeric character may be associated with each of the direction designation keys  11   a . More specifically, non-numeric characters and numeric characters are associated with the direction designation keys  11   a  such that, for example, a hiragana character “a” and numeric character “0” can be displayed on the display unit  21  even in a case in which any key composing the direction designation keys  11   a  is operated. Different non-numeric characters and numeric characters may be assigned to the plurality of keys composing the direction designation keys  11   a , respectively. In this case, for example, a hiragana character “a” and a numeric character “0” may be assigned to the upper key  111 , and a hiragana character “i” and a numeric character “1” may be assigned to the right key  113 . For example, a hiragana character “u” and a numeric character “2” may be assigned to the lower key  112 , and for example, a hiragana character “e” and a numeric character “3” may be assigned to the left key  114 . 
     The non-numeric characters and the numeric characters associated with the direction designation keys  11   a  are not limited to the above example. Non-numeric characters and numeric characters assigned to the direction designation keys  11   a  (the upper key  111 , the lower key  112 , the right key  113  or the left key  114 ) may be non-numeric characters and numeric characters that are initially set, or may be non-numeric characters and numeric characters that are set by a user. 
     In a case in which any key of the direction designation keys  11   a  is operated, the control unit  45  causes the display unit  21  to display at least one of a non-numeric character and a numeric character associated with the key thus operated. For example, in a case in which the hiragana character “a” and the numeric character “0” are associated with all of the keys composing the direction designation keys  11   a , when any key of the direction designation keys  11   a  is operated, the control unit  45  causes the display unit  21  to display at least one of the hiragana character “a” and the numeric character “0”. In a case in which the hiragana character “a” and the numeric character “0” are assigned to the upper key  111 , when the upper key  111  is operated, the control unit  45  causes the display unit  21  to display at least one of the hiragana character “a” and the numeric character “0”. 
     Here, at a point in time when any key of the direction designation keys  11   a  is operated to cause the display unit  21  to display a non-numeric character and a numeric character, any one of the following screens are being displayed on the display unit  21 : a standard screen (a screen that is displayed in a standby state for communication or an operation of the input key, in which other applications are not running); and a screen (editor screen) for inputting non-numeric characters and numeric characters. 
     As a result, with the mobile telephone device  1 , in a case in which any key of the direction designation keys  11   a  is operated, the display unit  21  displays at least one of a non-numeric character and a numeric character associated with the key thus operated; therefore, at least one of the non-numeric character and the numeric character can be input, based on an operation of the direction designation keys  11   a.    
     Next,  FIG. 3  is a first diagram for illustrating a non-numeric character palette  21   c  and a numeric character palette  21   d .  FIG. 4  is a second diagram for illustrating the non-numeric character palette  21   c  and the numeric character palette  21   d.    
     In a state where the standard screen is displayed on the display unit  21 , in a case in which any key of the direction designation keys  11   a  is operated, it is preferable for the control unit  45  to cause the display unit  21  to display a non-numeric character and a numeric character associated with the key thus operated, and the non-numeric character palette  21   c  composed of a plurality of non-numeric characters used for changing a non-numeric character to an other non-numeric character. The non-numeric character palette  21   c  may be, for example, a hiragana character palette based on the Japanese syllabary (see  FIGS. 3 and 4 ). 
     In a case in which any key of the direction designation keys  11   a  is operated, the control unit  45  causes the display unit  21  to display a non-numeric character and a numeric character associated with the key thus operated, and the non-numeric character palette  21   c . At this time, a cursor for selecting a non-numeric character is displayed in the non-numeric character palette  21   c . In a state where a non-numeric character and a numeric character as well as the non-numeric character palette  21   c  are displayed on the display unit  21 , in a case in which any key of the direction designation keys  11   a  is further operated, the control unit  45  moves the cursor toward a direction corresponding to the key thus operated. For example, in a state where the cursor is in a position of the hiragana character “           ” (pronounces as “a”) in the non-numeric character palette  21   c , in a case in which the left key  114  is operated, the control unit  45  moves the cursor to a position of a hiragana character “ka” that is immediately on the left of the hiragana character “a” in the non-numeric character palette  21   c . Based on the movement of the cursor, the control unit  45  changes the hiragana character “a” displayed on the display unit  21  to the hiragana character “ka”.
     As a result, with the mobile telephone device  1 , in a case in which any key of the direction designation keys  11   a  is operated, a non-numeric character and a numeric character associated with the key thus operated as well as the non-numeric character palette  21   c  are displayed, and in a case in which any key of the direction designation keys  11   a  is further operated, the cursor in the non-numeric character palette  21   c  is moved to select another non-numeric character; therefore, characters can be input, based on an operation of the direction designation keys  11   a . With the mobile telephone device  1 , since characters can be input by using the non-numeric character palette  21   c , a character input is visualized so that characters can be easily input. 
     In a state where the standard screen is displayed on the display unit  21 , in a case in which any key of the direction designation keys  11   a  is operated, the control unit  45  may cause the display unit  21  to display the numeric character palette  21   d  (see  FIGS. 3 and 4 ) composed of a plurality of numeric characters used for changing a numeric character to an other numeric character. 
     In the aforementioned case, hiragana characters are displayed in the non-numeric character palette  21   c . However, instead of hiragana characters, alphabetic characters may be displayed in the non-numeric character palette. In this case, in a state where the non-numeric character palette  21   c  is displayed on the display unit  21 , in a case in which any key of the direction designation keys  11   a  is operated, the control unit  45  moves the cursor toward a direction corresponding to the key thus operated. For example, in a state where the cursor is in a position of an alphabetic character “f” in the non-numeric character palette  21   c , in a case in which the left key  114  is operated, the control unit  45  moves the cursor to a position of an alphabetic character “e” that is immediately on the left of the alphabetic character “f” in the non-numeric character palette  21   c . Based on the movement of the cursor, the control unit  45  changes the alphabetic character “f” displayed on the display unit  21  to the alphabetic character “e”. 
     In a case in which the control unit  45  causes the display unit  21  to display a non-numeric character and a numeric character, it is preferable for the control unit  45  to cause the display unit  21  to display a non-numeric character input area  21   a  for inputting non-numeric characters, and a numeric character input area  21   b  for inputting numeric characters. In a case in which the right key  113  or the left key  114  is operated, it is preferable for the control unit  45  to maintain the displaying of the non-numeric character input area  21   a  for inputting non-numeric characters as well as the non-numeric character thus displayed, and to cancel the displaying of the numeric character input area  21   b  for inputting numeric characters as well as the numeric character thus displayed. 
     As exemplified in  FIGS. 3 and 4 , the control unit  45  causes the display unit  21  to display the non-numeric character input area  21   a  on an upper side of the display unit  21 , and to display the numeric character input area  21   b  on a lower side of the display unit  21 . In the present embodiment, the non-numeric character palette  21   c  is displayed in the non-numeric character input area  21   a . As shown in the numeric character palette  21   d  shown in  FIGS. 3 and 4 , in a case in which the right key  113  or the left key  114  is operated, the control unit  45  cannot change the numeric character displayed in the numeric character input area  21   b  to an other numeric character, then cancels the displaying of the numeric character input area  21   b , and causes the non-numeric character input area  21   a  to be displayed on the entire surface of the display unit  21 . In a case in which the non-numeric character input area  21   a  is displayed on the entire surface of the display unit  21 , the control unit  45  may use the numeric character input area  21   b  for displaying predictive conversion candidates for converting the non-numeric character, which is input and displayed in the non-numeric character input area  21   a , to an other non-numeric character, word or symbol. 
     As a result, with the mobile telephone device  1 , in a case in which a non-numeric character and a numeric character are displayed on the display unit  21 , the display unit  21  displays the non-numeric character input area  21   a  and the numeric character input area  21   b , and in addition, in a case in which the right key  113  or the left key  114  is operated, the display unit  21  maintains the displaying of the non-numeric character input area  21   a , and cancels the displaying of the numeric character input area  21   b ; therefore, the visibility of the display unit  21  can be improved. 
     It is preferable for predetermined functions to be assigned to the direction designation keys  11   a , respectively. In this case, in a case in which any key of the direction designation keys  11   a  is operated, the control unit  45  causes the display unit  21  to perform displaying based on a predetermined function assigned to the key thus operated, and to display at least one of a non-numeric character and a numeric character associated with the key thus operated. In a state where the displaying based on the predetermined function and the non-numeric character or the numeric character are displayed on the display unit  21 , in a case in which any key of the direction designation keys  11   a  is further operated, it is preferable for the control unit  45  to select an other non-numeric character and an other numeric character for changing at least one of the non-numeric character and the numeric character displayed on the display unit  21  to the other non-numeric character and the other numeric character, respectively, and to cause the display unit  21  to display the other non-numeric character and the other numeric character thus selected; alternatively, it is preferable for the control unit  45  to select a display item based on the predetermined function, and to cause the display unit  21  to display the display item thus selected. 
     The predetermined function is, for example, an outgoing call history function, an incoming call history function, an address book function, a news display function, etc. In a case in which any key of the direction designation keys  11   a  is operated, the control unit  45  causes the display unit  21  to display at least one of the non-numeric character input area  21   a  and the numeric character input area  21   b , as well as an area that is displayed based on the predetermined function (for example, an area for displaying outgoing call history). In a state where a plurality of areas are displayed on the display unit  21 , in a case in which any key of the direction designation keys  11   a  is further operated, the control unit  45  changes the non-numeric character displayed in the non-numeric character input area  21   a  to an other non-numeric character, or changes the numeric character displayed in the numeric character input area  21   b  to an other numeric character. Alternatively, for example, in a state where the display unit  21  displays a plurality of outgoing call histories as a display item based on the predetermined function, in a case in which a single outgoing call history is selected by operating the direction designation keys  11   a , the control unit  45  causes the display unit  21  to display the outgoing call history thus selected. 
     As a result, with the mobile telephone device  1 , by operating the direction designation keys  11   a , the display unit  21  displays a numeric character or a non-numeric character assigned to the key thus operated, and the display unit  21  also performs displaying based on a predetermined function assigned to the key thus operated; therefore, it is possible to avoid conflict of functions (non-numeric characters, numeric characters, and predetermined functions) assigned to the direction designation keys  11   a.    
     It is preferable for a non-numeric character, a numeric character and a predetermined function to be associated with each of the direction designation keys  11   a . In this case, in a state where the standard screen is displayed on the display unit  21 , in a case in which any key of the direction designation keys  11   a  is operated, the control unit  45  causes the display unit  21  to display a non-numeric character and a numeric character associated with the key thus operated, and to perform displaying based on a predetermined function associated with the key thus operated. 
     In a case in which any key of the direction designation keys  11   a  is operated, the control unit  45  causes the display unit  21  to display the non-numeric character input area  21   a  into which the non-numeric character associated with the key thus operated is input, the numeric character input area  21   b  into which the numeric character associated with the key thus operated is input, and the area for performing the displaying based on the predetermined function associated with the key thus operated. 
     As a result, with the mobile telephone device  1 , in a case in which any key of the direction designation keys  11   a  is operated, the control unit  45  causes the display unit  21  to display the non-numeric character input area  21   a , the numeric character input area  21   b , and the area for performing the displaying based on the predetermined function; therefore, functions (a non-numeric character, a numeric character, and a predetermined function) assigned to the key thus operated can be confirmed in the same screen. 
     Next, descriptions are provided for a first operation of the mobile telephone device  1  of the present embodiment.  FIG. 5  is a flow chart for illustrating the first operation of the mobile telephone device  1 .  FIG. 6  is a diagram for illustrating screen transition in the first operation of the mobile telephone device  1 . 
     In Step S 101  shown in  FIG. 5 , in a state where the standard screen is displayed on the display unit  21  (see FIG.  6 ), in a case in which any key (the lower key  112  in a case shown in  FIG. 6 ) of the direction designation keys  11   a  is operated, the control unit  45  detects that the direction designation key  11   a  is operated. 
     In Step S 102 , the control unit  45  activates an editor capable of inputting non-numeric characters and numeric characters. 
     In Step S 103 , the control unit  45  causes the display unit  21  to display the non-numeric character input area  21   a  and the numeric character input area  21   b , and to display the non-numeric character palette  21   c  in the non-numeric character input area  21   a.    
     In Step S 104 , the control unit  45  causes a non-numeric character (an initial value: a hiragana character “           ” (“a”) in this case) corresponding to the key (the lower key  112  in this case) detected in Step S 101  to be input and displayed in the non-numeric character input area  21   a . In this case, the control unit  45  places the cursor in a position of the hiragana character “         ” (“a”) in the non-numeric character palette  21   c.  
     In Step S 105 , the control unit  45  causes a numeric character (an initial value: a numeric character “0” in this case) corresponding to the key (the lower key  112  in this case) detected in Step S 101  to be input and displayed in the numeric character input area  21   b  (see  FIG. 6C ). It should be noted that the processing from Step S 103  to Step S 105  may be executed concurrently or separately. 
     In Step S 106 , the control unit  45  determines whether an operation of the upper key  111  or the lower key  112  is detected. More specifically, the control unit  45  determines whether the key detected in Step S 101  is the upper key  111  or the lower key  112 . In a case in which the operated key is not the upper key  111  or the lower key  112  (No), the processing advances to Step S 107 . In a case in which the operated key is the upper key  111  or the lower key  112  (Yes), the processing advances to Step S 113 . 
     In Step S 107 , the control unit  45  determines whether an operation of the right key  113  or the left key  114  is detected. More specifically, the control unit  45  determines whether the key detected in Step S 101  is the right key  113  or the left key  114 . In a case in which the operated key is the right key  113  or the left key  114  (Yes), the processing advances to Step S 108 . In a case in which the operated key is not the right key  113  or the left key  114  (No), the processing advances to Step S 116 . 
     In Step S 108 , the control unit  45  changes a displayed character. More specifically, the control unit  45  changes a non-numeric character displayed in the non-numeric character input area  21   a  to an other non-numeric character. 
     In Step S 109 , control unit  45  updates the position of the cursor on non-numeric character palette  21   c . The control unit  45  moves the position of the cursor in the non-numeric character palette  21   c  in the direction to the left or right (in a case shown in  FIG. 6 , in the direction to the left) (see  FIG. 6D ). The processing in Steps S 108  and S 109  may be executed concurrently or separately. 
     In Step S 110 , the control unit  45  determines whether the key detected in Step S 101  is the left key  114 . In a case in which the key is not the left key  114  (No), the processing advances to Step S 111 . In a case in which the key is the left key  114  (Yes), the processing advances to Step S 112 . 
     In a case in which the numeric character palette  21   d  as shown in  FIG. 3  is displayed in the numeric character input area  21   b , in Step S 111 , the control unit  45  determines the numeric character that is input into the numeric character input area  21   b , and moves the position of the cursor in the numeric character palette  21   d  to the right. 
     In a case in which the numeric character palette  21   d  as shown in  FIG. 3  is displayed in the numeric character input area  21   b , in Step S 112 , the control unit  45  does not execute the processing of changing the numeric character to an other numeric character, and the processing of determining the numeric character that is input into the numeric character input area  21   b  (NOP). 
     In Step S 113 , the control unit  45  updates the displayed character. More specifically, the control unit  45  changes the non-numeric character displayed in the non-numeric character input area  21   a  to an other non-numeric character. For example, in a state where the cursor is displayed in a position of a hiragana character “           ” (pronounced as “ka”) in the non-numeric character palette  21   c , in a case in which the lower key  112  is operated four times, the control unit  45  changes the hiragana character “         ” (“ka”), which is input into the non-numeric character input area  21   a , to a hiragana character “         ” (pronounced as “ko”).
     In Step S 114 , the control unit  45  moves the position of the cursor in the non-numeric character palette  21   c  in the upper or lower direction (here, the lower direction) (see  FIG. 6E ). 
     In Step S 115 , the control unit  45  increases a count of a number in a case in which an operation of the upper key  111  was detected in Step S 106 , and the control unit  45  decreases the count of the number in a case in which an operation of the lower key  112  was detected in Step S 106 . The processing from Step S 113  to Step S 115  may be executed concurrently or separately. 
     In Step S 116 , the control unit  45  detects whether a determination key  115  composing the direction designation keys  11   a  is operated. The determination key  115  is, for example, a key (a center key) for executing determination processing of a non-numeric character or a numeric character. In a case in which the determination key  115  is not operated (No), the processing returns to Step S 106 . In a case in which the determination key  115  is operated (Yes), the processing advances to Step S 117 . 
     In Step S 117 , the control unit  45  changes the position of a non-numeric character cursor. More specifically, the control unit  45  moves the position of the non-numeric character cursor for inputting a non-numeric character into the non-numeric character input area  21   a  to the right. 
     In Step S 118 , the control unit  45  determines the numeric character that is input into the numeric character input area  21   b , and updates the position of a numeric character cursor for inputting a numeric character into the numeric character input area  21   b . More specifically, the control unit  45  moves the numeric character, which was input and established in the numeric character input area  21   b , to the left by one character such that a new numeric character can be input (see  FIG. 6F ). The processing in Steps S 117  and S 118  may be executed concurrently or separately. 
     Next, descriptions are provided for a second operation of the mobile telephone device  1  of the present embodiment.  FIG. 7  is a flow chart for illustrating the second operation of the mobile telephone device  1 . 
     In Step S 201 , in a state where the standard screen is displayed on the display unit  21 , in a case in which any key of the direction designation keys  11   a  is operated, the control unit  45  detects that the direction designation key  11   a  is operated. 
     In Step S 202 , the control unit  45  activates the editor capable of inputting non-numeric characters and numeric characters. 
     In Step S 203 , the control unit  45  causes the display unit  21  to display the non-numeric character input area  21   a  and the numeric character input area  21   b , and to display the non-numeric character palette  21   c  in the non-numeric character input area  21   a.    
     In Step S 204 , the control unit  45  causes a non-numeric character corresponding to the key thus operated (the key detected in Step S 201 ) to be input and displayed in the non-numeric character input area  21   a . In this case, the control unit  45  places the cursor, for example, in a position of the hiragana character “a” in the non-numeric character palette  21   c.    
     In Step S 205 , a numeric character corresponding to the key thus operated (the key detected in Step S 201 ) is input and displayed in the numeric character input area  21   b . The processing from Step S 203  to Step S 205  may be executed concurrently or separately. 
     In Step S 206 , the control unit  45  determines whether an operation of the upper key  111  or the lower key  112  is detected. More specifically, the control unit  45  determines whether the key detected in Step S 201  is the upper key  111  or the lower key  112 . In a case in which the operated key is not the upper key  111  or the lower key  112  (No), the processing advances to Step S 207 . In a case in which the operated key is the upper key  111  or the lower key  112  (Yes), the processing advances to Step S 213 . 
     In Step S 207 , the control unit  45  determines whether an operation of the right key  113  or the left key  114  is detected. More specifically, the control unit  45  determines whether the key detected in Step S 201  is the right key  113  or the left key  114 . In a case in which the operated key is the right key  113  or the left key  114  (Yes), the processing advances to Step S 208 . In a case in which the operated key is not the right key  113  or the left key  114  (No), the processing advances to Step S 215 . 
     In Step S 208 , the control unit  45  determines whether the key detected in Step S 201  is the right key  113 . In a case in which the operated key is the right key  113  (Yes), the processing advances to Step S 209 . In a case in which the operated key is not the right key  113  (No), the processing advances to Step S 211 . 
     In Step S 209 , the control unit  45  determines the numeric character that is input into the numeric character input area  21   b , and moves the position of the numeric character cursor for inputting a numeric character into the numeric character input area  21   b.    
     In Step S 210 , the control unit  45  moves the position of the cursor in the non-numeric character palette  21   c  to the right. The processing in Steps S 209  and S 210  may be executed concurrently or separately. 
     In Step S 211 , the control unit  45  determines whether a numeric character is input into the numeric character input area  21   b . In a case in which the numeric character is input into the numeric character input area  21   b  (Yes), the processing advances to Step S 212 . In a case in which the numeric character is not input into the numeric character input area  21   b  (No), the processing advances to Step S 215 . 
     The control unit  45  executes processing of moving the position of the numeric character cursor for inputting a numeric character into the numeric character input area  21   b . More specifically, the control unit  45  moves the numeric character, which was input and established in the numeric character input area  21   b , to the left by one character such that a new numeric character can be input (see  FIG. 6F ). 
     In Step S 213 , the control unit  45  moves the position of the cursor displayed in the non-numeric character palette  21   c  in the upper or lower direction. 
     In Step S 214 , the control unit  45  increases a count of a number in a case in which an operation of the upper key  111  was detected in Step S 206 , and the control unit  45  decreases the count of the number in a case in which an operation of the lower key  112  was detected in Step S 206 . The processing in Steps S 213  and S 214  may be executed concurrently or separately. 
     In Step S 215 , the control unit  45  detects whether the determination key  115  composing the direction designation keys  11   a  is operated. The determination key  115  is, for example, a key (a center key) for executing determination processing of a non-numeric character or a numeric character. In a case in which the determination key  115  is not operated (No), the processing returns to Step S 206 . In a case in which the determination key  115  is operated (Yes), the processing advances to Step S 216 . 
     In Step S 216 , the control unit  45  executes processing of cancelling the numeric character input area  21   b  displayed on the display unit  21 . In other words, the control unit  45  causes the display unit  21  to display the non-numeric character input area  21   a  on the entire surface of the display unit  21 . 
     In Step S 217 , the control unit  45  causes the display unit  21  to display a conversion candidate area for converting a non-numeric character displayed in the non-numeric character input area  21   a  into an other non-numeric character. For example, in a case in which a hiragana character string “Yokohama” is displayed in the non-numeric character input area  21   a , the control unit  45  causes the display unit  21  to display the conversion candidate area, into which non-numeric characters serving as conversion candidates such as kanji character strings “Yokohama”, “Yokohama City” and “Yokohama Station” are input. The processing in Steps S 216  and S 217  may be executed concurrently or separately. 
     In Step S 218 , the control unit  45  detects that any conversion candidate is selected and determined from a plurality of conversion candidates displayed in the conversion candidate area. In the above example, in a case in which the kanji character string “Yokohama”, which is input into the conversion candidate area, is selected and established, the control unit  45  converts the hiragana character string “Yokohama” displayed in the non-numeric character input area  21   a  into the kanji character string “Yokohama”. 
     In Step S 219 , the control unit  45  determines whether the processing of terminating a character input is executed. In other words, the control unit  45  determines whether the processing of terminating a character input is selected through an operation by the user. In a case in which the processing of terminating a character input is not selected (No), the processing returns to Step S 206 . In a case in which the processing of terminating a character input is selected (Yes), the processing is terminated. 
     Next, descriptions are provided for a third operation of the mobile telephone device  1  of the present embodiment.  FIG. 8  is a flow chart for illustrating the third operation of the mobile telephone device  1 . 
     In Step S 201 , in a state where the editor for inputting non-numeric characters and numeric characters is running, in a case in which any key of the direction designation keys  11   a  is operated, the control unit  45  detects that the direction designation key  11   a  is operated. 
     In Step S 302 , the control unit  45  causes a non-numeric character corresponding to the key thus operated (the key detected in Step S 301 ) to be input and displayed in the non-numeric character input area  21   a.    
     In Step S 303 , the control unit  45  causes a numeric character corresponding to the key thus operated (the key detected in Step S 301 ) to be input and displayed in the numeric character input area  21   b . The processing in Steps S 302  and S 303  may be executed concurrently or separately. 
     In Step S 304 , the control unit  45  determines whether the numeric characters input into the numeric character input area  21   b  have three digits. In a case in which the numeric characters do not have three digits (No), the processing advances to Step S 305 . In a case in which the numeric characters have three digits (Yes), the processing advances to Step S 308 . 
     In Step S 305 , the control unit  45  determines whether the numeric characters input into the numeric character input area  21   b  have the number of digits that enables an outgoing telephone call (for example, 10 digits, 11 digits with the initial numeric character 0, or 14 digits with a prefix number). In a case in which the numeric characters do not have the number of digits that enables an outgoing telephone call (No), the processing advances to Step S 306 . In a case in which the numeric characters have the number of digits that enables an outgoing telephone call (Yes), the processing advances to Step S 309 . 
     In Step S 306 , the control unit  45  determines whether the number of digits of the numeric characters input into the numeric character input area  21   b  exceeds the number of digits (14 digits) that enables an outgoing telephone call. In a case in which the number of digits exceeds the number of digits that enables an outgoing telephone call (No), the processing returns to Step S 301 . In a case in which the number of digits does not exceed the number of digits that enables an outgoing telephone call (Yes), the processing advances to Step S 307 . 
     In Step S 307 , the control unit  45  cancels the numeric character input area  21   b  from the display unit  21 . In other words, the control unit  45  causes the display unit  21  to display only the non-numeric character input area  21   a . After the processing in Step S 307 , the processing advances to character input processing. 
     In Step S 304 , the control unit  45  determines whether the numeric characters input into the numeric character input area  21   b  are a telephone number for making an urgent call such as “110”, “118” or “119”. In a case in which the numeric characters are not a telephone number for making an urgent call (No), the processing advances to Step S 305 . In a case in which the numeric characters are a telephone number for making an urgent call (Yes), the processing advances to Step S 309 . 
     In Step S 309 , the control unit  45  causes the display unit  21  to display a software key, to which an “outgoing call” function is assigned. Here, a key image of the software key displayed on the display unit  21  corresponds to any of the keys composing the operation unit. The function assigned to the key is executed by operating the key corresponding to the key image. 
     In Step S 310 , in a case in which the “outgoing call” software key displayed in Step S 309  is operated, the control unit  45  detects an “outgoing call” operation. 
     In Step S 311 , the control unit  45  cancels the non-numeric character input area  21   a  displayed on the display unit  21 . In other words, the control unit  45  causes the display unit  21  to display the non-numeric character input area  21   a  on the entire surface of the display unit  21 . After the processing in Step S 311 , the processing advances to outgoing call processing. 
     Next, descriptions are provided for a fourth operation of the mobile telephone device  1  of the present embodiment. The fourth operation is an operation for the display unit  21  to display the non-numeric character input area  21   a  and to perform displaying regarding a predetermined function in a case in which any key of the direction designation keys  11   a  is operated; and the fourth operation is similar to the aforementioned first operation (the operation for the display unit  21  to display the non-numeric character input area  21   a  and the numeric character input area  21   b  in a case in which any key of the direction designation keys  11   a  is operated). Accordingly, descriptions are provided for the fourth operation of the mobile telephone device  1  with reference to only the drawings ( FIGS. 8 and 10 ) illustrating screen transition. 
     First of all, descriptions are provided for a first example of the fourth operation.  FIG. 9  is a first diagram for illustrating screen transition in the fourth operation of the mobile telephone device  1 . 
     In a state where the standard screen is displayed (see  FIG. 9A ), in a case in which any key (here, the right key  113 ) of the direction designation keys is operated, the control unit  45  causes the display unit  21  to display the non-numeric character input area  21   a  including the non-numeric character palette  21   c , and to perform displaying regarding a predetermined function (here, the outgoing call history function) (see  FIG. 9B ). 
     Next, in a case in which the lower key  112  is operated for a plurality of times (here, four times), the control unit  45  moves the cursor in the non-numeric character palette  21   c  in the lower direction, and changes a hiragana character “           ” (pronounced as “wa”) displayed in the non-numeric character input area  21   a  to an other hiragana character “         ” (pronounced as “wo”). The control unit  45  changes the outgoing call history (scrolling in the lower direction; see  FIG. 9C ).
     Next, in a case in which the lower key  112  is operated for a plurality of times (here, four times), the control unit  45  moves the cursor to the top line in the same column of the non-numeric character palette  21   c , and thereafter moves the cursor in the lower direction again. The control unit  45  changes the hiragana character “           ” (“wo”) displayed in the non-numeric character input area  21   a  to an other hiragana character “         ” (pronounced as “e”). The control unit  45  changes the outgoing call history (scrolling in the lower direction). Here, since the cursor continuously moves in the same column of the non-numeric character palette  21   c , and a determination operation is not performed (more specifically, in a case in which the same key of the direction designation keys  11   a  is consecutively operated for more than a predetermined number of times), the control unit  45  determines that an operation for inputting a non-numeric character into the non-numeric character input area  21   a  is not being performed, and causes the display unit  21  to display a notification pictogram  21   e  (see  FIG. 9D ). It should be noted that a shape of the notification pictogram  21   e  is not limited to the shape shown in the  FIG. 9D .
     Next, in a state where the notification pictogram  21   e  is displayed, in a case in which the lower key  112  is further operated (in a case of performing an operation that is less likely to input a character), the control unit  45  cancels the non-numeric character input area  21   a  from the display unit  21 , and displays an outgoing call history on the entire surface of the display unit  21  (see  FIG. 9E ). 
     Descriptions are provided for a second example of the fourth operation.  FIG. 10  is a second diagram for illustrating screen transition in the fourth operation of the mobile telephone device  1 . In a state where the standard screen is displayed (see  FIG. 10A ), in a case in which any key (here, the right key  113 ) of the direction designation keys  11   a  is operated, the control unit  45  causes the display unit  21  to display the non-numeric character input area  21   a  including the non-numeric character palette  21   c , and to perform displaying regarding a predetermined function (here, the outgoing call history function) (see  FIG. 10B ). 
     Next, in a case in which the lower key  112  is operated, the control unit  45  changes the hiragana character “           ” (“wa”) input into the non-numeric character input area  21   a  to the other hiragana character “         ” (pronounces as “i”), and moves the cursor in the non-numeric character palette  21   c  in the lower direction. The control unit  45  changes the outgoing call history (scrolling in the lower direction; see  FIG. 10C ).
     Next, in a case in which a calling key (not shown) is operated, the control unit  45  causes the display unit  21  to display the outgoing call history, which is displayed in a state shown in  FIG. 10C , on the entire surface of the display unit  21  (see  FIG. 10D ). 
     In a state shown in  FIG. 10B , in a case in which the right key  113  is operated, the control unit  45  moves the cursor in the non-numeric character palette  21   c  to the right, and changes the hiragana character “           ” (“wa”) displayed in the non-numeric character input area  21   a  to an other hiragana character “         ” (pronounced as “ra”). Here, since the outgoing call history displayed on the display unit  21  is changed by only the upper key  111  or the lower key  112 , the control unit  45  determines that the operation of the right key  113  is not an operation for changing the outgoing call history, and causes the display unit  21  to display the notification pictogram  21   e  (see  FIG. 10E ). A shape of the notification pictogram  21   e  is not limited to the shape shown in the  FIG. 10E .
     Next, in a state where the notification pictogram  21   e  is displayed, in a case in which the right key  113  is further operated (in a case in which the outgoing call history is not changed), the control unit  45  cancels the outgoing call history from the display unit  21 , and displays the non-numeric character input area  21   a  on the entire surface of the display unit  21  (see  FIG. 9E ). 
     Next, descriptions are provided for a fifth operation of the mobile telephone device  1  of the present embodiment.  FIG. 11  is a flow chart for illustrating the fifth operation of the mobile telephone device  1 .  FIG. 12  is a diagram for illustrating screen transition in the fifth operation of the mobile telephone device  1 . 
     In Step S 401 , in a state where the standard screen is displayed (see  FIG. 12A ), in a case in which any key (here, the right key  113 ) of the direction designation keys  11   a  is operated, the control unit  45  detects that the direction designation key  11   a  is operated. 
     In Step S 402 , the control unit  45  executes processing of activating a function (here, the outgoing call history function) corresponding to right key  113  thus operated. 
     In Step S 403 , the control unit  45  activates the editor for inputting non-numeric characters and numeric characters. The processing in Steps S 402  and S 403  may be executed concurrently or separately. 
     In Step S 404 , the control unit  45  executes processing of generating image data for causing the display unit  21  to display an outgoing call history as well as a hiragana character “           ” (“wa”) and a numeric character “0” assigned to the right key  113  thus operated.
     In Step S 405 , the control unit  45  executes display updating processing of causing the display unit  21  to perform displaying based on the image data generated in Step S 404  (see  FIG. 12B ). Furthermore, the control unit  45  executes processing of causing the display unit  21  to display software keys of “conversion”, “selection” and “outgoing call”. 
     In Step S 406 , the control unit  45  determines whether a further operation of the direction designation keys  11   a  is detected. In a case in which an operation of the direction designation keys  11   a  is detected (Yes), processing corresponding to the operation of the direction designation keys  11   a  is executed. In a case in which an operation of the direction designation keys  11   a  is not detected (No), the processing advances to Step  407 . 
     In Step S 407 , the control unit  45  detects whether a software key is operated. 
     In Step S 408 , the control unit  45  determines whether the software key, of which operation was detected in Step S 407 , is “conversion”. In a case in which an operation of “conversion” is detected (Yes), the processing advances to Step S 409 . In a case in which an operation of “conversion” is not detected (No), the processing advances to Step S 412 . 
     In Step S 409 , the control unit  45  reads, from storage unit, conversion candidate data for converting the hiragana character “           ” (“wa”) displayed on the display unit  21  into an other non-numeric character or the like.
     In Step S 410 , the control unit  45  generates display data of the non-numeric character input area  21   a  displayed on the display unit  21 . 
     In Step S 411 , the control unit  45  executes processing of updating the displaying of the display unit  21 , based on the conversion candidate data that was read in Step S 409 , and the display data of the non-numeric character input area  21   a  that was generated in Step S 410 . 
     In Step S 412 , the control unit  45  determines whether the software key, of which operation was detected in Step S 407 , is “outgoing call”. 
     In Step S 413 , the control unit  45  determines whether the numeric characters displayed on the display unit  21  in Step S 405  can be used as a telephone number for making an outgoing call. In a case in which the numeric characters can be used as a telephone number for making an outgoing call (Yes), the processing advances to call originating processing. In a case in which the numeric characters cannot be used as a telephone number for making an outgoing call (No), the processing advances to Step  414 . 
     In Step S 414 , the control unit  45  generates display data of the numeric character input area  21   b  displayed on the display unit  21 . 
     In Step S 415 , the control unit  45  executes processing of updating the displaying of the display unit  21 , based on the display data generated in Step S 414  (see  FIG. 12D ). 
     After the processing in Step S 415 , the processing advances to numeric character input processing. 
     In Step S 416 , the control unit  45  determines that the software key, of which operation was detected in Step S 407 , is “selection”. 
     After the processing in Step S 416 , the processing advances to processing of operating a predetermined function. 
     The present invention is not limited to the aforementioned embodiment, and can be implemented as various embodiments. 
     Although the aforementioned embodiment has been described for a case in which the mobile telephone device  1  is configured with a single direction designation key  11   a  (composed of the upper key  111 , the right key  113 , the lower key  112  and the left key  114 ), the present invention is not limited to this configuration. Therefore, the direction designation keys may be composed of a plurality of keys. In other words, the upper key, the right key, the lower key and the left key may be mutually independent keys. 
     Moreover, although the aforementioned embodiment has been described for a case in which the direction designation keys  11   a  are composed of hardware keys, the present invention is not limited to this configuration. In other words, in a case of a touch panel including a touch sensor, the direction designation keys may be displayed as software keys on the touch panel. 
     Second Embodiment 
     First of all, with reference to  FIG. 13 , descriptions are provided for a basic structure of a mobile telephone device according to a second embodiment of the electronic device of the present invention.  FIG. 13  is a perspective view showing an appearance of a mobile telephone device  1  according to the second embodiment of the electronic device. 
     The mobile telephone device  1  is a mobile telephone device of a straight type. An external shape of the mobile telephone device  1  is mainly configured with: a case  2 ; a removable member  3  that is removably attached to the case  2 ; and a strap  4  that is connected to the removable member  3 . The mobile telephone device  1  has a security alarm function in addition to a telephone call function. The security alarm function is a function to draw attention of people around a user by operating the mobile telephone device  1  to generate sound at full blast, in a case in which the user sensed danger. 
     An operation unit  11 , a display unit  21 , a microphone  12  and a speaker  22  are disposed on a front face  2   a  of the case  2 . 
     The operation unit  11  includes a plurality of direction designation keys  11   a  (direction designating means) for designating distinct directions, a function activation key  11   b  for activating a predetermined function and the like, and a determination key  11   c  (determining means) for performing a determination operation and the like. Here, even in a case in which the plurality of direction designation keys  11   a  are physically composed of a single key as shown in  FIG. 13 , such a key is assumed to be a plurality of direction designation keys as long as different functions are assigned to upper, right, lower and left directions, respectively. More specifically, such means may be capable of designating a plurality of directions, and may be a joystick, a track ball, or other pointing devices. Detection through a capacitive sensor or an infrared sensor may be employed to enable designation of a plurality of directions. 
     In the present invention, the direction designation keys  11   a  of the operation unit  11  perform not only a direction designation operation and a scroll operation in upper, lower, left and right directions, but also an input operation of symbols including numeric characters, non-numeric characters, alphabetic characters and the like. Here, the present invention assumes that a numeric character includes not only a single numeric character but also a numeric character string, a character includes not only a single character but also a character string, an alphabetic character includes not only a single alphabetic character but also an alphabetic character string, and a symbol includes not only a single symbol but also a symbol string. The direction designation keys  11   a  include an upper key  111  capable of designating the upper direction, a lower key  112  capable of designating the lower direction, a right key  113  capable of designating the right direction, and a left key  114  capable of designating the left direction. 
     Characters include non-numeric characters other than numeric characters, such as, for example, hiragana characters, katakana characters, alphabetic characters, symbols and the like. 
     For example, in a standby state for communication, in which a predetermined application is not running, i.e. in a state where a standard screen (also referred to as an idle screen) is displayed on the display unit  21 , when any key of the direction designation keys  11   a  is operated, a character associated with the key thus operated is input. The character thus input is displayed on the display unit  21 . The character thus input is used for inputting a character for a character input application or the like by a predetermined operation. In a state where a screen based on a predetermined application, for example, a character input screen based on a mail application, is displayed on the display unit  21 , when any key of the direction designation keys  11   a  is operated, a character associated with the key thus operated is input. The character thus input is displayed on the display unit  21 . 
     Based on an operation of the function activation key  11   b  of the operation unit  11 , the control unit  45  to be described below executes each application such as a telephone directory application, a mail application, and a Web application. 
     A predetermined function is assigned to each key, in accordance with a type of an application that is running. In a case in which a user operates a key, i.e. depresses a key, the control unit  45  to be described below executes an operation in accordance with a function assigned to the key thus operated. 
     Based on an operation of the determination key  11   c  of the operation unit  11 , the control unit  45  to be described below performs determination and the like of various operations. For example, when a character is input, the determination key  11   c  performs a determination operation such as determining a character selected by the direction designation keys  11   a . Here, in the present invention, when the determination key  11   c  is depressed, a character palette and any of a conversion candidate or a prediction candidate are selected. 
     The display unit  21  is composed of a liquid crystal display, an organic EL (electroluminescence) display or the like. In a standby state for communication, in which a predetermined application is not running, the standard screen (also referred to as the idle screen) is displayed on the display unit  21 . In a case in which a predetermined application is running, a screen based on an operation of the application is displayed. For example, in the standby state for communication, the preset standard screen is displayed on the display unit  21 . In a state where a character is input in the mail application, a character input screen is displayed. 
     The display unit  21  displays a first area  100  for displaying a plurality of characters that can be selected as characters to be input. Here, a so-called character palette is displayed in the first area  100 . An example of the character palette may include, for example, hiragana characters arranged in the order of the Japanese syllabary based on vowels and consonants (see the first area  100  in  FIG. 15 ). The display unit  21  displays a second area  200  for displaying conversion candidates or prediction candidates for an input character (see the second area  200  in  FIG. 15 ; a plurality of prediction candidates are displayed in  FIG. 15 ). The display unit  21  displays a third area  300  adjacently to the first area  100  and the second area  200  (see the third area  300  in  FIG. 15 ). The display unit  21  displays a character input area  400  for displaying an input character. 
     The microphone  12  inputs sound produced by the user of the mobile telephone device  1  during a telephone call. The speaker  22  outputs sound of the other party of a telephone call when using the mobile telephone device  1 . 
     The mobile telephone device is not limited to the mobile telephone device  1  of the straight type described above. In other words, the mobile telephone device may be of: a slider type in which one case slides to one direction from a state in which the operation unit side case and the display unit side case are mutually superimposed; a rotating type in which one case is rotated around an axis line along the superimposing direction; a type in which the display unit side case and the operation unit side case are connected via a 2-axis hinge; or a flip type in which the display unit side case and the operation unit side case are connected via a hinge mechanism. 
     Next, descriptions are provided for a functional configuration of the mobile telephone device  1 .  FIG. 14  is a functional block diagram showing functions of the mobile telephone device  1  according to the second embodiment. The mobile telephone device  1  includes the operation unit  11  (including the direction designation keys  11   a , the function activation key  11   b , and the determination key  11   c ), the microphone  12 , the display unit  21 , and the speaker  22 . The mobile telephone device  1  internally includes: a main antenna  40 , an RF circuit unit  41 , an image processing unit  42 , a sound processing unit  43 , memory  44 , and the control unit  45 . The configurations of the operation unit  11 , the microphone  12 , the display unit  21  and the speaker  22  are as described above. 
     The main antenna  40  communicates with external devices such as base stations via a predetermined usable frequency band (for example, 800 MHz band). Although 800 MHz is set as the predetermined usable frequency band in the present embodiment, other frequency bands can also be used. 
     The RF circuit unit  41  executes demodulation processing on a signal received via the main antenna  40 , and transmits the processed signal to the control unit  45 . The RF circuit unit  41  executes modulation processing on a signal transmitted from the control unit  45 , and transmits the signal to external devices via the main antenna  40 . On the other hand, the RF circuit unit  41  notifies the control unit  45  of the intensity of a signal received via the main antenna  40 . 
     The image processing unit  42  executes predetermined image processing, and outputs the processed image data to a driver IC, in accordance with control by the control unit  45 . When the image data is transmitted from the image processing unit  42 , the driver IC stores the image data in frame memory, and outputs the image data to the display unit  21  at predetermined timing. 
     The sound processing unit  43  executes predetermined sound processing on a signal transmitted from the RF circuit unit  41 , and outputs the processed signal to the speaker  22 , in accordance with control by the control unit  45 . The speaker  22  externally outputs the signal that is transmitted from the sound processing unit  43 . 
     When a signal is input from the microphone  12 , the sound processing unit  43  processes the signal, and outputs the processed signal to the RF circuit unit  41 , in accordance with control by the control unit  45 . The RF circuit unit  41  executes predetermined processing on the signal transmitted from the sound processing unit  43 , and outputs the processed signal to the main antenna  40 . 
     The memory  44  includes, for example, working memory, and is utilized for arithmetic processing by the control unit  45 . The memory  44  stores a plurality of applications as well as various tables and the like that are required by the applications. The memory  44  may also serve as detachable external memory. 
     The control unit  45  controls the entirety of the mobile telephone device  1 , and is configured to employ a central processing unit (CPU) and the like. The control unit  45  performs predetermined control of the image processing unit  42 , the sound processing unit  43 , and the memory  44 . 
     In a state where the standard screen or the character input screen is displayed on the display unit  21 , in a case in which any key of the direction designation keys  11   a  (the upper key  111 , the lower key  112 , the right key  113  and the left key  114 ) is further operated, the control unit  45  causes the display unit  21  to display a character associated with the key thus operated in the character input area  400 . In a state where a character is displayed in the character input area  400  of the display unit  21 , in a case in which any key of the direction designation keys  11   a  (the upper key  111 , the lower key  112 , the right key  113  and the left key  114 ) is further operated (in a case in which any direction is designated by the direction designation key  11   a ), the control unit  45  performs selection for changing the displayed character to an other character, and causes the display unit  21  to display the other character thus selected in the character input area  400 . 
     More specifically, for example, in a state where the standard screen is displayed on the display unit  21 , in a case in which any key of the direction designation keys  11   a  (for example, the upper key  111 ) is operated, the control unit  45  causes the display unit  21  to display a character (for example, a hiragana character “           ” (“a”)) associated with the key thus operated in the character input area  400 . Characters to be input when operating the keys may be associated in advance with the direction designation keys  11   a , respectively, or may be arbitrarily set by the user. In a state where the hiragana character “a” is displayed in the character input area  400  of the display unit  21 , in a case in which the lower key  112  of the direction designation keys  11   a  is further operated, the control unit  45  assumes that selection has been made for changing the hiragana character “         ” (“a”) to an other hiragana character “         ” (pronounced as “i”) that is displayed in a direction designated in the first area  100  (see the first area  100  in  FIG. 15  regarding the layout of the characters), and the control unit  45  causes the display unit  21  to display the other hiragana character “         ” (“i”) thus selected in the character input area  400 . In a state where the hiragana character “         ” (“i”) is displayed in the character input area  400  of the display unit  21 , in a case in which the left key  114  of the direction designation keys  11   a  is further operated, the control unit  45  assumes that an operation has been made for changing the hiragana character “         ” (“i”) to an other hiragana character “         ” (pronounced as “ki”) that is displayed in a direction designated in the first area  100  (see the first area  100  in  FIG. 15  regarding the layout of the characters), and the control unit  45  causes the display unit  21  to display the other hiragana character “         ” (“ki”) thus selected in the character input area  400 . In a state where the hiragana character “ki” is displayed in the character input area  400  of the display unit  21 , when the determination key  11   c  is operated, the control unit  45  determines the input of the hiragana character “ki”. Subsequently, a character following the hiragana character “ki” can be input.
     In this way, in a case in which any key of the direction designation keys  11   a  (the upper key  111 , the lower key  112 , the right key  113  and the left key  114 ) is operated, the mobile telephone device  1  causes the display unit  21  to display a character. In a case in which any key of the direction designation keys  11   a  (the upper key  111 , the lower key  112 , the right key  113  and the left key  114 ) is further operated, the mobile telephone device  1  changes the character displayed on the display unit  21  to an other character, and causes the display unit  21  to display the other character. As a result, a character can be input, based on an operation of the direction designation keys  11   a.    
     In a case in which any key of the direction designation keys  11   a  (for example, the upper key  111 ) is operated, it is also possible to cause the character input area  400  of the display unit  21  to display an alphabetic character (for example “a”) assigned to the upper key  111 . In a state where the alphabetic character “a” is displayed in the character input area  400  of the display unit  21 , in a case in which the lower key  112  of the direction designation keys  11   a  is further operated, the control unit  45  assumes that selection has been made for changing the alphabetic character “a” to an other alphabetic character “k” that is displayed in a direction designated in the first area  100  (a layout of alphabetic characters is not illustrated), and the control unit  45  causes the display unit  21  to display the other alphabetic character “k” thus selected in the character input area  400 . 
     Incidentally, in a case in which a character is input by using the direction designation keys, the number of keys for inputting characters is limited. As a result, a problem as follows has been suffered. For example, in a case in which the user selects a character from the character palette that displays characters that can be input, and the user inputs a desired character by using conversion candidates or predictive candidates for the character, the user had to separately use the input using the character palette and the input using conversion candidates or predictive candidates by way of the direction designation keys, and such an operation has been complicated. 
     Accordingly, in order to solve the problem as described above, the control unit  45  according to the present embodiment performs control as follows. More specifically, in a state where the third area  300  is selected, in a case in which the determination key  11   c  is operated, the control unit  45  selects the second area  200  or a conversion candidate or a prediction candidate displayed in the second area  200 , and in a case in which any of the direction designation key  11   a  is operated, the control unit  45  selects the first area  100  or a character displayed in the first area  100 . Alternatively, in a state where the third area  300  is selected, in a case in which the determination key  11   c  is operated, the control unit  45  selects the first area  100  or a character displayed in the first area  100 , and in a case in which any of the direction designation key  11   a  is operated, the control unit  45  selects the second area  200  or a conversion candidate or a prediction candidate displayed in the second area  200 . 
     As a specific example, in a state where the standard screen is displayed on the display unit  21 , when a hiragana character “a” is input by an operation of the upper key  111  of the direction designation keys  11   a , the control unit  45  causes the display unit  21  to display the hiragana character “a” in the character input area  400 . The display unit  21  displays: the first area  100  as a character palette for displaying characters that can be selected as input characters; the second area  200  for displaying predictive candidates for the hiragana character “a”; and the third area  300  that is adjacent to the first area  100  and the second area  200 . In a state where the third area  300  is selected, in a case in which the determination key  11   c  is operated, the control unit  45  selects the second area  200  or a prediction candidate displayed in the second area  200 . Alternatively, in a state where the third area  300  is selected, in a case in which any of the direction designation keys  11   a  is operated, the control unit  45  selects the first area  100  or a character displayed in the first area  100 . 
     In this manner, in a state where the third area  300  adjacent to the first area  100  and the second area  200  is selected, the mobile telephone device  1  can determine whether the first area  100  or the second area  200  is selected, based on whether the determination key  11   c  is operated or any of the direction designation keys  11   a  is operated without operating the determination key  11   c . Thus, the first area  100  and the second area  200  can be separately used in an effective manner. Therefore, the user can easily input a desired character without complicated operations. 
     First of all, descriptions are provided for a sixth operation of the mobile telephone device  1  with reference to  FIG. 16 . First of all, the sixth operation postulates that the standard screen is displayed on the display unit  21  (see  FIG. 16A ). In a state where the standard screen is displayed on the display unit  21 , in a case in which any key of the direction designation keys  11   a  (for example, the upper key  111 ) is operated, the control unit  45  causes the display unit  21  to display a character (here, a hiragana character “           ” (“a”)) associated with the key thus operated (see  FIG. 16B ) in the character input area  400 . In addition, the display unit  21  displays: the first area  100  for displaying a plurality of characters that can be selected as input characters; the second area  200  for displaying a plurality of conversion candidates for the hiragana character “         ” (“a”); and the third area  300  that is adjacent to the first area  100  and the second area  200  (see  FIG. 16B ).
     As shown in  FIG. 16B , in a state where the hiragana character “           ” (“a”) is displayed in the upper right corner of the first area  100 , and is selected by a cursor  60  (see the first area  100  in  FIG. 15  regarding the layout of characters), when the upper direction is designated by the upper key  111 , since there is no character in the upper direction from the hiragana character “         ” (“a”) in the first area  100 , the control unit  45  selects the third area  300  by the cursor  50  (see  FIG. 16C ).
     In a state where the third area  300  is selected by the cursor  50 , in a case in which the determination key  11   c  is operated, and the upper direction is designated by the upper key  111 , the control unit  45  controls that a kanji character “           ” (pronounced as “a”) displayed in the upper left corner is selected by the cursor  50  from a plurality of conversion candidates in the second area  200  that is displayed above the third area  300 , and the kanji character “         ” (“a”) is displayed in the character input area  400  of the display unit (see  FIG. 16D ).
     In a state where the third area  300  is selected by the cursor  50 , in a case in which the determination key  11   c  is not operated, and the upper direction is designated by the upper key  111 , the control unit  45  controls that a hiragana character “           ” (pronounced as “o”) displayed in the lower right corner is selected by the cursor  50  from a plurality of hiragana characters in the first area  100  that is displayed below the third area  300 , and the hiragana character “         ” (“o”) is displayed in the character input area  400  of the display unit  21  (see  FIG. 16E ). A so-called toggle operation is performed.
     In this manner, in a case in which a desired character is input by using the direction designation keys  11   a , in a state where the third area  300  is selected, the mobile telephone device  1  determines whether the first area  100  or the second area  200  is selected, based on whether the determination key  11   c  is operated or any of the direction designation keys  11   a  is operated without operating the determination key  11   c . Thus, the first area and the second area can be separately used. Therefore, the user can easily input a desired character. 
     Here, in the sixth operation, in a state where the standard screen is displayed on the display unit  21 , in a case in which any key of the direction designation keys  11   a  (for example, the upper key  111 ) is operated, the character input area  400  of the display unit  21  displays a character associated with the key thus operated. However, the sixth operation is not limited thereto, and a character may be input into the character input area  400  of the display unit  21  by an operation of any of the direction designation keys  11   a , in a state where a character input screen in the mail application or the like is displayed on the display unit  21 . The direction designating keys  11   a  are not limited to the upper key  111 , and may be the lower key  112 , the right key  113 , and the left key  114 . 
     In the sixth operation, a character is input as selected by the cursor  50 . However, the sixth operation is not limited thereto, and a character may be input only when a key such as the determination key is operated after selecting the character by the cursor  50 . It is preferable for the determination key to be a center key, which is the so-called determination key  11   c  surrounded by the direction designation keys  11   a , but it is not limited thereto. 
     In the sixth operation, in a state where the third area  300  is selected, in a case in which the determination key  11   c  is operated, and the upper direction is designated by the upper key  111 , the kanji character “           ” (“a”) displayed in the upper left corner is input and displayed, from the plurality of conversion candidates displayed in the second area  200  that is displayed above the third area  300 . However, the sixth operation is not limited thereto, and a katakana character “         ” (pronounced as “a”) displayed in the right corner may be input and displayed, and any character displayed in the second area  200  may be input and displayed. In the sixth operation, even if the upper key  111  is not operated, in a case in which the determination key  11   c  is operated in a state where the third area  300  is selected, the kanji character “         ” (“a”) may be input from the plurality of conversion candidates in the second area  200 . In the sixth operation, the entire second area  200  may be selected instead of a single conversion candidate from a plurality of conversion candidates in the second area  200 .
     In the sixth operation, in a state where the third area  300  is selected, in a case in which the determination key  11   c  is operated, and the upper direction is designated by the upper key  111 , a single conversion candidate is selected from a plurality of conversion candidates in the second area  200  that is displayed above the third area  300 . However, in the sixth operation, in a case in which the determination key  11   c  is operated, and any of the lower key  112 , the right key  113  and the left key  114  is operated, a single conversion candidate may be selected from a plurality of conversion candidates in the second area  200  that is displayed above the third area  300 . 
     In the sixth operation, in a state where the third area  300  is selected, in a case in which the determination key  11   c  is not operated, and the upper direction is designated by the upper key  111 , the hiragana character “o” displayed in the lower right corner is input, from the plurality of conversion candidates displayed in the first area  100  that is displayed below the third area  300 . However, the sixth operation is not limited thereto, and the hiragana character “a” displayed in the upper right corner may be input again, and any character displayed in the first area  100  may be input. In the sixth operation, the entire first area  100  may be selected instead of a single character from a plurality of characters in the first area  100 . 
     In the sixth operation, in a state where the third area  300  is selected, in a case in which the determination key  11   c  is not operated, and the upper direction is designated by the upper key  111 , a single character is selected from a plurality of characters in the first area  100  that is displayed below the third area  300 . However, in the sixth operation, in a case in which the determination key  11   c  is not operated, and any of the lower key  112 , the right key  113  and the left key  114  is operated, a single character may be selected from a plurality of characters in the first area  100  that is displayed below the third area  300 . 
     In the sixth operation, in a state where the hiragana character “           ” (“a”) is displayed in the upper right corner of the first area  100  (see the first area  100  in  FIG. 15  regarding the layout of characters), in a case in which the upper direction is designated by the upper key  111 , the third area  300  is selected since there is no character in the upper direction from the hiragana character “         ” (“a”) (see  FIG. 16C ). However, the sixth operation is not limited thereto, and in a state where the hiragana character “         ” (“o”) being displayed in the lower right corner is selected (see the first area  100  in  FIG. 15  regarding the layout of characters), in a case in which the lower direction is selected by the lower key  112 , the third area  300  is selected since there is no character in the lower direction from the hiragana character “         ” (“o”). Furthermore, in the sixth operation, in a case in which the right direction is designated by the right key  113 , the third area  300  is selected since there is no character in the right direction from the hiragana character “         ” (“o”).
     Next, descriptions are provided for a seventh operation of the mobile telephone device  1  with reference to  FIG. 17 . First of all, the seventh operation postulates that a kanji character “           ” (“a”) is displayed on the display unit  21  (see  FIG. 17A ). The display unit  21  displays: the first area  100  for displaying a plurality of characters that can be selected as input characters; the second area  200  for displaying conversion candidates for the hiragana character “         ” (“a”); and the third area  300  that is adjacent to the first area  100  and the second area  200  (see  FIG. 17A ).
     As shown in  FIG. 17A , in a state where the kanji character “           ” (“a”) being displayed in the upper left corner of the second area  200  is selected, in a case in which the left direction is designated by the left key  114 , since there is no character in the left direction from the kanji character “         ” (“a”), the control unit  45  controls that the third area  300  is selected (see  FIG. 17B ).
     In a state where the third area  300  is selected, in a case in which the determination key  11   c  is operated, and the lower direction is designated by the lower key  112 , the control unit  45  controls that the hiragana character “           ” (“a”) displayed in the upper right corner is selected by the cursor  50  from a plurality of characters in the first area  100  that is displayed below the third area  300 , and the hiragana character “         ” (“a”) is displayed in the character input area  400  of the display unit  21  (see  FIG. 17C ).
     In a state where the third area  300  is selected by the cursor  50 , in a case in which the determination key  11   c  is not operated, and the lower direction is designated by the lower key  112 , the control unit  45  controls that a katakana character “           ” (“a”) displayed in the lower right corner is selected by the cursor  50  from a plurality of conversion candidates in the second area  200  that is displayed above the third area  300 , and the katakana character “         ” (“a”) is displayed in the character input area  400  of the display unit (see  FIG. 17D ). A so-called toggle operation is performed.
     In this manner, in a case in which a desired character is input by using the direction designation keys  11   a , in a state where the third area  300  is selected, the mobile telephone device  1  determines whether the first area  100  or the second area  200  is selected, based on whether the determination key  11   c  is operated or any of the direction designation keys  11   a  is operated without operating the determination key  11   c . Thus, the first area and the second area can be separately used. Therefore, the user can easily input a desired character. 
     Here, in the seventh operation, a character is input as selected by the cursor  50 . However, the seventh operation is not limited thereto, and a character may be input only when a key such as the determination key is operated after selecting the character by the cursor  50 . It is preferable for the determination key to be a center key, which is the so-called determination key  11   c  surrounded by the direction designation keys, but it is not limited thereto. 
     In the seventh operation, in a state where the third area  300  is selected, in a case in which the determination key  11   c  is operated, and the lower direction is designated by the lower key  112 , the hiragana character “a” displayed in the upper right corner is input, from the plurality of characters displayed in the first area  100  that is displayed below the third area  300 . However, the seventh operation is not limited thereto, and the hiragana character “o” displayed in the lower right corner may be input, and any character displayed in the first area  100  may be input. In the seventh operation, even if the lower key  112  is not operated, in a case in which the determination key  11   c  is operated in a state where the third area  300  is selected, the hiragana character “a” being displayed in the upper right corner may be input from the plurality of characters in the first area  100 . In the seventh operation, the entire first area  100  may be selected instead of a single character from a plurality of characters in the first area  100 . 
     In the seventh operation, in a state where the third area  300  is selected, in a case in which the determination key  11   c  is operated, and the lower direction is designated by the lower key  112 , a single character is selected from a plurality of characters in the first area  100  that is displayed below the third area  300 . However, in the seventh operation, in a case in which the determination key  11   c  is operated, and any of the upper key  111 , the right key  113  and the left key  114  is operated, a single character may be selected from a plurality of characters in the first area  100  that is displayed below the third area  300 . 
     In the seventh operation, in a state where the third area  300  is selected, in a case in which the determination key  11   c  is not operated, and the lower direction is designated by the lower key  112 , the katakana character “a” displayed in the lower right corner is input and displayed, from the plurality of conversion candidates displayed in the second area  200  that is displayed above the third area  300 . However, the seventh operation is not limited thereto, and the kanji character “a” displayed in the upper left corner may be input again, and any character displayed in the second area  200  may be input. In the seventh operation, the entire second area  200  may be selected instead of a single conversion candidate from a plurality of conversion candidates in the second area  200 . 
     In the seventh operation, in a state where the third area  300  is selected, in a case in which the determination key  11   c  is not operated, and the lower direction is designated by the lower key  112 , a single conversion candidate is selected from a plurality of conversion candidates in the second area  200  that is displayed above the third area  300 . However, in the seventh operation, in a case in which the determination key  11   c  is not operated, and any of the upper key  111 , the right key  113  and the left key  114  is operated, a single conversion candidate may be selected from a plurality of conversion candidates in the second area  200  that is displayed above the third area  300 . 
     In the seventh operation, in a state where the kanji character “           ” (“a”) being displayed in the upper left corner of the second area  200  is selected, in a case in which the left direction is designated by the left key  114 , since there is no character in the left direction from the kanji character “         ” (“a”), the third area  300  is selected (see  FIG. 17B ). However, the seventh operation is not limited thereto, and in a state where a kanji character “         ” (pronounced as “kaeru”) being displayed in the lower left corner is selected, in a case in which the left direction is designated by the left key  114 , since there is no character in the left direction from the kanji character “         ” (“kaeru”), the third area  300  is selected.
     In the sixth operation, in a case in which the determination key  11   c  is operated, and any of the direction designation keys  11   a  is operated, a single conversion candidate is selected from a plurality of conversion candidates in the second area  200 . In the seventh operation, in a case in which the determination key  11   c  is operated, and any of the direction designation keys  11   a  is operated, a single character is selected from a plurality of characters in the first area  100 . However, each of the operation examples is not limited thereto. In the sixth operation, in a case in which the determination key  11   c  is operated, and any of the direction designation keys  11   a  is operated, a single character may be selected from a plurality of characters in the first area  100 . In the seventh operation, in a case in which the determination key  11   c  is operated, and any of the direction designation keys  11   a  is operated, a single conversion candidate may be selected from a plurality of conversion candidates in the second area  200 . 
     Similarly, in the sixth operation, in a case in which the determination key  11   c  is not operated, and any of the direction designation keys  11   a  is operated, a single character is selected from a plurality of character in the first area  100 . In the seventh operation, in a case in which the determination key  11   c  is not operated, and any of the direction designation keys  11   a  is operated, a single conversion candidate is selected from a plurality of conversion candidates in the second area  200 . However, each of the operation examples is not limited thereto. In the sixth operation, in a case in which the determination key  11   c  is not operated, and any of the direction designation keys  11   a  is operated, a single conversion candidate may be selected from a plurality of conversion candidates in the second area  200 . In the seventh operation, in a case in which the determination key  11   c  is not operated, and any of the direction designation keys  11   a  is operated, a single character may be selected from a plurality of characters in the first area  100 . 
     In the sixth or seventh operation, in a state where the character palette for displaying characters of the Japanese syllabary based on vowels and consonants is displayed in the first area  100  (see the first area  100  in  FIG. 15 ), in a case in which a character displayed in the first area  100  is selected after selecting the third area  300 , the character may be selected such that the character has the same vowel or consonant as that of a character selected in the first area  100  immediately before selecting the third area  300 , and is different from the character that was selected. 
     More specifically, in each of the operation examples, in a case in which a hiragana character “a” is selected from a plurality of characters in the first area  100 , the third area  300  is selected, and an other character in the first area  100  is further selected, the other character may be selected such that the other character has the same vowel as that of the hiragana character “           ” (“a”) selected in the first area immediately before selecting the third area  300 , and the other character is different from the hiragana character “         ” (“a”) that was selected, i.e. any of hiragana characters “         ” (“ka”), “         ” (pronounces as “sa”), “         ” (pronounces as “ta”), “         ” (pronounces as “na”), “         ” (pronounces as “ha”), “         ” (pronounces as “ma”), “         ” (pronounces as “ya”), “         ” (pronounces as “ra”) and “         ” (pronounces as “wa”) may be selected (see the first area  100  in  FIG. 15  regarding the layout of the characters). In each of the operation examples, in a case in which the hiragana character “         ” (“a”) is selected from a plurality of characters in the first area  100 , the third area  300  is selected, and an other character in the first area  100  is further selected, the other character may be selected such that the other character has the same consonant as that of the hiragana character “         ” (“a”) selected in the first area immediately before selecting the third area  300 , and the other character is different from the hiragana character “         ” (“a”) that was selected, i.e. any of hiragana characters “         ” (“i”), “         ” (pronounced as “u”), “         ” (pronounced as “e”) and “         ” (“o”) may be selected (see the first area  100  in  FIG. 15  regarding the layout of the characters).
     The present invention is not limited to the aforementioned embodiment, and can be implemented as various embodiments. 
     Although the aforementioned embodiment has been described for a case in which the mobile telephone device  1  is configured with a single direction designation key  11   a  (composed of the upper key  111 , the right key  113 , the lower key  112  and the left key  114 ), the present invention is not limited to this configuration. Therefore, the direction designation keys may be composed of a plurality of keys. In other words, the upper key, the right key, the lower key and the left key may be mutually independent keys. 
     Although the aforementioned embodiment has been described for a case in which the direction designation keys  11   a  are composed of hardware keys, the present invention is not limited to this configuration. In other words, in a case of a touch panel including a touch sensor, the direction designation keys may be displayed as software keys on the touch panel. 
     Although the mobile telephone device and the like have been described above as the embodiments, the embodiments are intended to facilitate understanding of the present invention, and are not intended to interpret the present invention in a limited manner. Needless to mention, the present invention may be altered and/or improved without departing from the spirit thereof, and the present invention includes equivalents thereof. In particular, the present invention also includes an embodiment described below. 
     For example, the mobile telephone device  1  according to the first embodiment and the mobile telephone device  1  according to the second embodiment can be implemented in a crossover manner. In other words, the mobile telephone device can perform both of the operations described in the first embodiment and the operations described in second embodiment. 
     Moreover, the aforementioned embodiments have been described by illustrating the cases in which the present invention is applied to the mobile telephone device  1 . However, the present invention is not limited to the aforementioned embodiments, and may also be applied to an electronic device such as a PHS (Personal Handyphone System), a PDA (Personal Digital Assistant), a personal computer, a portable gaming device, a navigation device, or a remote controller.