Patent Publication Number: US-8538489-B2

Title: Mobile communication terminal

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application is a divisional of U.S. patent application Ser. No. 12/810,491, filed on Jun. 24, 2010, which is the U.S. National Stage Application of International Application No. PCT/JP2008/073590, filed on Dec. 25, 2008, and claims the benefit of Japanese Patent Application No. 2007-340604, filed on Dec. 28, 2007, each of which is incorporated herein by reference in its entirety. 
    
    
     TECHNICAL FIELD 
     The present invention relates to a mobile communication terminal, and more particularly to a mobile communication terminal which can be opened and closed. 
     BACKGROUND ART 
     Recently, many mobile phones are configured to be changeable in style in consideration of convenience of use and portability. Taking advantage of such a change in style, a technique of using a user&#39;s operation of changing the style of the mobile phone as an instruction to be input into the mobile phone has been developed. There is known a mobile phone which is configured such that, when a phonebook is opened while the mobile phone is in the folded state and then the phone body is opened, a call is originated to the party designated in the phonebook to enter a talk mode. During the call, other applications can be browsed when the phone body is closed, and the talk can be continued when the phone body is opened again. 
     In the case of a mobile terminal focusing on manipulability of the keyboard as well as visibility of the display, the mobile terminal may increase in size to the extent that it cannot be held with one hand in the open state. This mobile phone takes a form suitable for talking when it is closed rather than when it is open. Thus, talking on the phone may be difficult if the mobile phone needs to be opened in order to originate a call to enter a talk mode. 
     DISCLOSURE OF THE INVENTION 
     Problems to be Solved by the Invention 
     The present invention has been accomplished to solve the above-described problem, and an object of the present invention is to provide a mobile communication terminal in which an operation for talking thereon is facilitated. 
     Means for Solving the Problems 
     To achieve the above-described object, according to an aspect of the present invention, a mobile communication terminal includes: first and second display portion to display images, the first display portion being changed in state between an open state where a display surface of the second display portion is exposed and a closed state where the display surface of the second display portion is covered by the first display portion; state detecting portion to detect the open/closed state of the first display portion; destination number accepting portion to accept a telephone number of a call destination in the state where the open state is being detected by the state detecting portion; and communication control portion, in response to an event that the closed state is detected by the state detecting portion after the telephone number has been accepted by the destination number accepting portion, for originating a call to the accepted telephone number. 
     According to another aspect of the present invention, a mobile communication terminal includes: first and second display portion to display images, the first display portion being changed in state between an open state where a display surface of the second display portion is exposed and a closed state where the display surface of the second display portion is covered by the first display portion; state detecting portion to detect the open/closed state of the first display portion; and communication control portion to cause for causing the terminal to go off-hook in response to an event that the closed state is detected by the state detecting portion after an incoming call has been detected while the open state of the first display portion was being detected. 
     According to a further aspect of the present invention, a mobile communication terminal includes: display portion to display an image, the display portion being changed in state between an open state where a surface of an operation portion is exposed and a closed state where the surface of the operation portion is covered; state detecting portion to detect the open/closed state of the display portion; destination number accepting portion to accept a telephone number of a call destination in the state where the open state is being detected by the state detecting portion; and communication control portion, in response to an event that the closed state is detected by the state detecting portion after the telephone number has been accepted by the destination number accepting portion, for originating a call to the accepted telephone number. 
     According to yet another aspect of the present invention, a mobile communication terminal includes: display portion to display an image, the display portion being changed in state between an open state where a surface of an operation portion is exposed and a closed state where the surface of the operation portion is covered; state detecting portion to detect the open/closed state of the display portion; and communication control portion to cause the terminal to go off-hook in response to an event that the closed state is detected by the state detecting portion after an incoming call has been detected while the open state was being detected by the state detecting portion. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  is a perspective view of a mobile communication terminal in a closed state. 
         FIG. 1B  is a perspective view of the mobile communication terminal in an open state. 
         FIG. 2  is a functional block diagram schematically showing the hardware configuration of the mobile communication terminal. 
         FIG. 3  is a functional block diagram schematically showing the functions of a CPU included in the mobile communication terminal. 
         FIG. 4  shows an example of an address book display screen which is displayed during a call originating operation. 
         FIG. 5  shows an example of a calling screen. 
         FIG. 6  shows an example of an incoming call alert screen. 
         FIG. 7  is a flowchart illustrating an example of the flow of a call originating process performed while in the open state. 
         FIG. 8  is a flowchart illustrating an example of the flow of a call receiving process. 
     
    
    
     BEST MODES FOR CARRYING OUT THE INVENTION 
     Embodiments of the present invention will now be described with reference to the drawings. In the following description, like reference characters denote like parts, which have like names and functions, and therefore, detailed description thereof will not be repeated. 
     A mobile communication terminal  1  according to the present embodiment is changed in style between an open state and a closed state.  FIG. 1A  is a perspective view of the mobile communication terminal in the closed state.  FIG. 1B  is a perspective view of the mobile communication terminal in the open state. Referring to  FIGS. 1A and 1B , mobile communication terminal  1  includes a first display portion  2 , a second display portion  3 , and a housing portion  5  which supports first display portion  2  and second display portion  3  in a slidable manner. First display portion  2  and second display portion  3  each have an approximately rectangular parallelepiped shape. Housing portion  5  has a recess, in which first display portion  2  and second display portion  3  are housed when mobile communication terminal  1  is in the closed state, so that mobile communication terminal  1  attains an approximately rectangular parallelepiped shape. As such, mobile communication terminal  1  in the closed state has a shape suitable for talking thereon. 
     A speaker  11  and a microphone  13  are each arranged at a position on housing portion  5  that is other than the recess for receiving first display portion  2  and second display portion  3 . Therefore, speaker  11  and microphone  13  are exposed when mobile communication terminal  1  is in the closed state. 
     In the closed state, first display portion  2  lies on second display portion  3 . First display portion  2  includes a first liquid crystal display (LCD)  15  on its surface opposite from its other surface facing second display portion  3 , and a first touch panel  17  is provided overlaid on first LCD  15 . Second display portion  3  includes a second LCD  16  on its surface facing first display portion  2 , and a second touch panel  18  is provided overlaid on second LCD  16 . 
     As first display portion  2  lies on second display portion  3  in the closed state, first LCD  15  is exposed, whereas second LCD  16  is covered by first display portion  2 . Thus, when mobile communication terminal  1  is in the closed state, a user can touch first touch panel  17  but cannot touch second touch panel  18 . 
     In the state where mobile communication terminal  1  is closed, when first display portion  2  and second display portion  3  both slide, mobile communication terminal  1  attains the open state. Second display portion  3  slides in a direction opposite from the direction in which first display portion  2  slides. Second display portion  3  is biased by a spring provided in housing portion  5 , so that second display portion  3  is moved upward when it slides to a predetermined position. Thus, at the time when mobile communication terminal  1  is in the open state, as shown in  FIG. 1B , the display surface of first LCD  15  included in first display portion  2  and the display surface of second LCD  16  included in second display portion  3  become flush with each other. Accordingly, when mobile communication terminal  1  is in the open state, first LCD  15  and second LCD  16  are both exposed, allowing the user to look at the images displayed thereon. The screen area doubles as compared with the case where mobile communication terminal  1  is in the closed state, so that a large amount of information can be displayed. Furthermore, first touch panel  17  overlaid on first LCD  15  and second touch panel  18  overlaid on second LCD  16  are exposed as well, allowing the user to input instructions using a large area. 
     When mobile communication terminal  1  is in the open state, speaker  11  and microphone  13  are both exposed, enabling talking over the terminal. However, first display portion  2  and second display portion  3  protrude from housing portion  5 , and the display surface doubles that in the closed state, making it difficult for the user to talk while holding the terminal with the hand. The open state of mobile communication terminal  1  is suitable for displaying images and for the user to input operations. 
       FIG. 2  is a functional block diagram schematically showing the hardware configuration of the mobile communication terminal. Referring to  FIG. 2 , mobile communication terminal  1  includes: a CPU  21  which is responsible for overall control of mobile communication terminal  1 ; first LCD  15  and second LCD  16  each connected to CPU  21 ; a radio circuit  22  connected to an antenna  22 A; an open-state sensor  23 ; a closed-state sensor  24 , an operation portion  25  which accepts an input of a user operation; a card interface (I/F)  27 ; a codec portion  28 ; speaker  11  and microphone  13  connected to codec portion  28 ; a read only memory (ROM)  31  for storing a program to be executed by CPU  21  and others; a random access memory (RAM)  32  used as a work area for CPU  21 ; and an electronically erasable and programmable ROM (EEPROM)  33  which stores address book data and others in a non-volatile manner. 
     Radio circuit  22  is supplied with a radio signal which has been received by antenna  22 A. Radio circuit  22  demodulates the radio signal, and outputs the resultant signal to CPU  21 . In the case where the demodulated radio signal is an audio signal, CPU  21  outputs the audio signal to codec portion  28 . When radio circuit  22  receives a signal from CPU  21 , it modulates the signal, and outputs the modulated radio signal to antenna  22 A. CPU  21 , on receipt of an audio signal from codec portion  28 , outputs the audio signal to radio circuit  22 . When radio circuit  22  receives an incoming call, it outputs an incoming call signal to CPU  21 . When receiving an outgoing call signal from CPU  21 , radio circuit  22  calls a telephone number input from CPU  21 . 
     Codec portion  28  decodes an audio signal input from CPU  21 , converts the decoded digital audio signal to an analog signal, amplifies the same, and outputs the resultant signal to speaker  11  which serves as a receiver. When receiving an analog audio signal from microphone  13 , codec portion  28  converts the audio signal into a digital signal, codes the same, and outputs the coded audio signal to CPU  21 . 
     Open-state sensor  23  is ON when mobile communication terminal  1  is in the open state, and OFF when it is not in the open state. Closed-state sensor  24  is ON when mobile communication terminal  1  is in the closed state, and OFF when it is not in the closed state. Open-state sensor  23  and closed-state sensor  24  are connected to CPU  21 , and CPU  21  detects the style of mobile communication terminal  1  by detecting the states of open-state sensor  23  and closed-state sensor  24 . Here, open-state sensor  23  and closed-state sensor  24  both detect the position of first display portion  2 . 
     Operation portion  25  includes first touch panel  17  and second touch panel  18 . When an operation is input from operation portion  25 , CPU  21  performs processing in accordance with the input operation. CPU  21  reads a plurality of application programs stored in ROM  31  for execution. While these application programs are written in a program language such as C or JAVA (registered trademark), the program languages used for writing the application programs are not restricted thereto; any other program languages may be used. Further, while the plurality of application programs are stored in ROM  31  and loaded into mobile communication terminal  1 , the plurality of application programs may be written in a single program language, or in different program languages. That is, there may be a plurality of application programs written in different program languages. 
     First LCD  15  and second LCD  16  are controlled by CPU  21  to display images. It is noted that first LCD  15  and second LCD  16  may each be replaced with any device for displaying an image, which may be for example an organic electro-luminescence (EL) display. First touch panel  17  and second touch panel  18  each detect a position touched by a user when the user touches the panel surface with the finger or the like. First touch panel  17  and second touch panel  18  each output positional information indicating the detected position to CPU  21 . 
     EEPROM  33  stores address book data. In the address book data, for each user as a call destination, user identification information for identifying the user is associated with related information. The user identification information includes the user&#39;s full name, nickname or other short name, and face image obtained by picking up an image of the user&#39;s face. The related information includes a telephone number, e-mail address, group to which the user belongs, and memo. 
     Card I/F  27  is mounted with a removable memory card  27 A. Memory card  27 A may be, e.g., a CompactFlash, SmartMedia (registered trademark), secure digital (SD) memory card, memory stick, multimedia card (MMC), xD picture card, or the like. 
     CPU  21  is capable of accessing memory card  27 A via card I/F  27 . While it is here assumed that the program to be executed by CPU  21  is stored in flash ROM  31 , the program may be stored in memory card  27 A and read from memory card  27 A for execution by CPU  21 . The recording medium for storing the program is not restricted to memory card  27 A. It may be a flexible disk, a cassette tape, a magnetic disk, an optical disk (compact disc-ROM (CD-ROM), magnetic optical disc (MO), mini disc (MD), digital versatile disc (DVD)), an optical card, or a semiconductor memory such as a mask ROM, an EPROM, or the like. Still alternatively, mobile communication terminal  1  may be connected to the Internet via radio circuit  22  and the program may be downloaded from a computer connected to the Internet, to be executed by CPU  21 . As used herein, the “program” includes, not only the program directly executable by CPU  21 , but also a source program, a compressed program, an encrypted program, and others. 
       FIG. 3  is a functional block diagram schematically showing the functions of the CPU included in the mobile communication terminal. CPU  21  includes: a state detecting portion  51  which detects the state of mobile communication terminal  1 ; a communication control portion  53  which controls radio circuit  22 ; a destination number accepting portion  55  which accepts a destination to be called; a first display control portion  57  which controls first LCD  15 ; a first instruction accepting portion  59  connected to the first touch panel; a second display control portion  61  which controls second LCD  16 ; and a second instruction accepting portion  63  connected to the second touch panel. 
     State detecting portion  51  detects the state of mobile communication terminal  1 . State detecting portion  51  detects the open state when open-state sensor  23  is ON. State detecting portion  51  detects the closed state when closed-state sensor  24  is ON. When open-state sensor  23  and closed-state sensor  24  are both OFF, state detecting portion  51  detects a state that is neither the closed state nor the open state. State detecting portion  51  outputs a state signal indicating the detected state of mobile communication terminal  1  to communication control portion  53  and second display control portion  61 . 
     First display control portion  57  controls first LCD  15  to display an image on first LCD  15 . First display control portion  57  outputs the image displayed on first LCD  15  to first instruction accepting portion  59 . 
     First instruction accepting portion  59  is connected to first touch panel  17 , and accepts from first touch panel  17  a position signal which indicates the position on the first touch panel touched by a person with the finger or the like. First instruction accepting portion  59  detects a command assigned to a predetermined position on the image in accordance with the image input from first display control portion  57  and the position signal input from first touch panel  17 . 
     Second display control portion  61  controls second LCD  16  to display an image on second LCD  16 . Second display control portion  61  outputs the image displayed on second LCD  16  to second instruction accepting portion  63 . Second display control portion  61  switches the image to be displayed on second LCD  16  in accordance with a command output from first instruction accepting portion  59 . This allows an image associated with the image being displayed on first LCD  15  to be displayed on second LCD  16 . 
     Second instruction accepting portion  63  is connected to second touch panel  18 , and accepts from second touch panel  18  a position signal which indicates the position on the first touch panel touched by a person with the finger or the like. Second instruction accepting portion  63  detects a command assigned to a predetermined position on the image in accordance with the image input from second display control portion  61  and the position signal input from second touch panel  18 . 
     An example of displaying, on second LCD  16 , an image associated with the image being displayed on first LCD  15  will now be described in conjunction with the case where a user uses an address book to originate a call. When first instruction accepting portion  59  or second instruction accepting portion  63  accepts an instruction to display an address book, first display control portion  57  reads address book data stored in EEPROM  33  and displays images of a plurality of pieces of user identification information included in the address book data on first LCD  15 . In this state, when the user designates one of the plurality of images of user identification information displayed on first LCD  15  with the finger, first instruction accepting portion  59  specifies the user identification information from the image being displayed in the designated position, and outputs the user identification information to second display control portion  61  and destination number accepting portion  55 . 
     Second display control portion  61 , on receipt of the user identification information from first instruction accepting portion  59 , searches the address book data stored in EEPROM  33  and causes second LCD  16  to display an image of related information that is associated with the user identification information. The related information includes the name, group, telephone number, e-mail address, memo, and others included in the address book data. 
       FIG. 4  shows an example of an address book display screen which is displayed during a call originating operation. Referring to  FIG. 4 , a list screen is displayed on first LCD  15  provided in first display portion  2 , and a related screen including the related information is displayed on second LCD  16  provided in second display portion  3 . 
     The list screen displayed on first LCD  15  includes images of the plurality of pieces of user identification information included in the address book data, which images are laid out systematically. Here, the user identification information includes the user name and face image. 
     The related screen displayed on second LCD  16  includes related information which is associated by the address book data with the user identification information selected in the list screen. The related screen shown here is displayed when the user designates the name “ ” as the user identification information. In the list screen, the image of the user identification information designated by the user is displayed brighter than the other images, to make it distinguishable from the images of the other user identification information. 
     While it is here assumed that the information included in the address book data is displayed as the related information, in the case where EEPROM  33  stores therein transmitted and received e-mails as well as annual, monthly, and daily schedule data, then the related information may include the e-mail transmitted to or received from the user corresponding to the user identification information input from first instruction accepting portion  59 , and the schedule data including the user identification information of that user. The related information displayed on second LCD  16  allows the user, before originating a call, to confirm the information that has been lately exchanged with the intended party, or to confirm the past or future schedule. 
     Returning to  FIG. 3 , destination number accepting portion  55 , on receipt of the user identification information from first instruction accepting portion  59 , searches the address book data stored in EEPROM  33 , and outputs the telephone number associated with the user identification information, to communication control portion  53 . 
     Communication control portion  53  controls radio circuit  22 . Communication control portion  53  receives a state signal indicating the state of mobile communication terminal  1  from state detecting portion  51 , and receives a telephone number of a call destination from destination number accepting portion  55 . In the state where a state signal indicating the open state is being input, when a telephone number of a call destination is input from destination number accepting portion  55  and then a state signal indicating the closed state is received, communication control portion  11  causes radio circuit  22  to originate a call to the destination number received from destination number accepting portion  55  and to connect the line when there is an answer from the call destination. Communication control portion  53  outputs to first display control portion  57  communication state signals indicating the communication states from when communication control portion  53  causes radio circuit  22  to originate a call till when the line is disconnected. 
     First display control portion  57 , on receipt of a communication state signal from radio circuit  22 , displays a screen indicating the communication state on first LCD  15 . The screen indicating the communication state includes: a calling screen which is displayed on first LCD  15  during calling, from when communication control portion  53  originates a call till when an answer is received from the call destination; and an active call screen which indicates that the line has been connected and the call is active. 
       FIG. 5  shows an example of the calling screen. The calling screen is displayed when mobile communication terminal  1  is in the closed state. Referring to  FIG. 5 , the calling screen includes a message “calling” for notifying the user that the call is being originated, the name and face image as the user identification information of the call destination, and the telephone number. This allows the user to know that mobile communication terminal  1  is calling the user named “AI”. 
     Returning to  FIG. 3 , in the case where radio circuit  22  receives an incoming call while the state signal indicating the open state is being input from state detecting portion  51 , communication control portion  53  outputs to second display control portion  61  an incoming call signal indicating that there is an incoming call. Thereafter, when the state signal indicating the closed state is input, communication control portion  53  causes radio circuit  22  to take the terminal off-hook, so as to connect the line. 
     On the other hand, in the case where an incoming call signal is input from communication control portion  53  while in the open state, second display control portion  61  displays on second LCD  16  an incoming call alert screen for notifying the user that there is an incoming call. In the open state, an image may have already been displayed on second LCD  16 , in which case second display control portion  61  displays the incoming call alert screen in preference to the image that has been displayed. For example, the incoming call alert screen may be displayed overlaid on the image being displayed. In this case, the incoming call alert screen is preferably displayed in such a manner that the underlying image can be seen through the incoming call alert screen. Alternatively, the image that has been displayed may be replaced with the incoming call alert screen. 
       FIG. 6  shows an example of the incoming call alert screen. Referring to  FIG. 6 , a menu screen is displayed on first LCD  15 , while a video image of television broadcast is displayed on second LCD  16 . The menu screen is a screen for a user to select an application program. On second LCD  16 , the incoming call alert screen including the message “incoming call” is displayed overlaid on the video image of the television broadcast. 
       FIG. 7  is a flowchart illustrating an example of the flow of a call originating process performed while in the open state. The call originating process is carried out by CPU  21  included in mobile communication terminal  1 , when mobile communication terminal  1  is in the open state, as CPU  21  executes a communication program. Referring to  FIG. 7 , CPU  21  determines whether an operation of instructing display of an address book has been accepted (step S 01 ). CPU  21  is in a standby mode until an operation of instructing display of the address book is accepted (NO in step S 01 ), and once the operation of instructing display of the address book is accepted (YES in step S 01 ), the process proceeds to step S 02 . On the menu screen displayed on first LCD  15 , when the user touches an icon associated with the operation of instructing display of the address book with the finger, the operation of instructing display of the address book is accepted from first touch panel  17 . 
     In step S 02 , the list screen, as shown in  FIG. 4 , is displayed on first LCD  15 . It is then determined whether one of the images of the plurality of pieces of user identification information included in the list screen has been designated (step S 03 ). The positions of the images of the plurality of pieces of user identification information displayed on first LCD  15  and the positional information input from first touch panel  17  are used to determine which one of the images of the user identification information has been designated. In the case where one of the images of the plurality of pieces of user identification information has been designated, the process proceeds to step S 04 ; otherwise, the process returns to step S 02 . 
     In step S 04 , related information that is related to the designated user identification information is extracted. The address book data stored in EEPROM  33  are searched to specify the address book data including the designated user identification information, and the related information included in the specified address book data is extracted. Here, the related information includes the telephone number, e-mail address, group to which the intended user belongs, and memo. 
     In step S 05 , the telephone number included in the related information extracted in step S 04  is extracted so as to specify the telephone number for calling. The related information extracted in step S 04  is displayed on second LCD  16  (step S 06 ). This allows the user, prior to calling, to confirm the related information about the user as a call destination. Furthermore, in the state where the list screen is being displayed on first LCD  15 , the related information that is related to the user identification information selected from that list screen is displayed on second LCD  16 , allowing the user to readily select the call destination. 
     In step S 07 , it is determined whether the closed state has been detected as the state of mobile communication terminal  1 . In other words, it is determined whether the state of mobile communication terminal  1  has been changed from the open state to the closed state. Specifically, it is determined whether closed-state sensor  24  has changed from OFF to ON. If the closed state has been detected, the process proceeds to step S 08 ; otherwise, the process returns to step S 03 . That is, the user can select a user as the call destination until when mobile communication terminal  1  attains the closed state. 
     In step S 08 , a call is originated to the telephone number specified in step S 05 . It is then determined whether an answer has been received from the phone of the call destination (step S 09 ). If the answer has been received, the process proceeds to step S 10 ; otherwise, the process is terminated. 
     In step S 10 , the line is connected to start conversation. The call is continued until an end of conversation (NO in step S 11 ), and once the conversation is over (YES in step S 11 ), the process is terminated. The end of conversation is detected when the line is disconnected or when the user inputs into first touch panel  17  an operation of instructing the end of conversation. 
       FIG. 8  is a flowchart illustrating an example of the flow of a call receiving process. The call receiving process is carried out by CPU  21  included in mobile communication terminal  1  as CPU  21  executes the communication program. Referring to  FIG. 8 , CPU  21  determines whether an incoming call has been detected (step S 21 ). The incoming call is detected when radio circuit  22  receives an incoming call. CPU  21  is in a standby mode until an incoming call is detected (NO in step S 21 ). Once the incoming call is detected (YES in step S 21 ), the process proceeds to step S 22 . 
     In step S 22 , it is determined whether the open state has been detected as the state of mobile communication terminal  1 . In other words, the state of mobile communication terminal  1  upon reception of the incoming call is determined. Specifically, the open state is detected when open-state sensor  23  is ON, while the closed state is detected when closed-state sensor  24  is ON. If the open state has been detected, the process proceeds to step S 23 ; otherwise, the process proceeds to step S 39 . 
     In step S 23 , an incoming call alert screen is displayed on second LCD  16 . The incoming call alert screen includes the message “incoming call”. The incoming call alert screen is displayed in preference to the image that has already been displayed. This ensures that the user is notified of the incoming call. The message is displayed superimposed on the already displayed image. In this case, the incoming call alert screen is preferably displayed in such a manner that the underlying image can be seen through the incoming call alert screen. While it is here assumed that the incoming call alert screen is displayed on second LCD  16 , it may be displayed on first LCD  15 , or on both first LCD  15  and second LCD  16 . Furthermore, in addition to the display of the incoming call screen, sound, vibration, light, or a combination thereof may be used for notifying of an incoming call. 
     In step S 24 , it is determined whether the closed state has been detected as the state of mobile communication terminal  1 . In other words, it is determined whether the state of mobile communication terminal  1  has been changed from the open state to the closed state. Specifically, it is determined whether closed-state sensor  24  has changed from OFF to ON. If the closed state has been detected, the process proceeds to step S 25 ; otherwise, the process proceeds to step S 37 . 
     In step S 37 , it is determined whether the calling is continued. If radio circuit  22  is receiving the incoming call, it is determined that the calling is continued. If the calling is continued, the process returns to step  24 ; otherwise, the process proceeds to step  38 . That is, while radio circuit  22  is receiving the incoming call, the process waits until mobile communication terminal  1  attains the closed state. Once mobile communication terminal  1  attains the closed state, the process proceeds to step S 25 . 
     In step S 38 , a screen notifying of incoming call history is displayed on second LCD  16 , and the process is terminated. The screen notifying of the incoming call history includes the message “incoming call” and the caller&#39;s telephone number. This can reliably notify the user that there was a call. While it is here assumed that the screen notifying of the incoming call history is displayed on second LCD  16 , it may be displayed on first LCD  15 , or on both first LCD  15  and second LCD  16 . Furthermore, in addition to the display of the screen notifying of the incoming call history, light or the like may be used to notify that there was a call. 
     In step S 25 , radio circuit  22  is caused to take the terminal off-hook. As a result, the line is connected to enable conversation. In the following step S 26 , a first display screen being displayed on first LCD  15  is stored in EEPROM  33 , and in the following step S 27 , a second display screen being displayed on second LCD  16  is stored in EEPROM  33 . Then, in step S 28 , a calling screen is displayed on first LCD  15 . This allows the user to know that mobile communication terminal  1  has moved to the active call state where the user can talk on the terminal. 
     A conversation process is then performed over the connected line (step S 29 ). In the case where there is an incoming call while mobile communication terminal  1  is in the open state, the user only needs to perform an operation of changing the state of mobile communication terminal  1  to the closed state so as to respond to the incoming call to start conversation. This facilitates the operation of answering the incoming call. 
     In step S 30 , it is determined whether the open state has been detected as the state of mobile communication terminal  1 . In other words, it is determined whether the state of mobile communication terminal  1  has been changed from the closed state to the open state. Specifically, it is determined whether open-state sensor  23  has changed from OFF to ON. If the open state has been detected, the process proceeds to step S 31 ; otherwise, the process proceeds to step S 34 . 
     In step S 34 , it is determined whether an on-hook key has been depressed. If the on-hook key has been depressed, the process proceeds to step S 35 ; otherwise, the process returns to step S 29 . The on-hook key may be a hard key arranged on housing portion  5 , or a soft key displayed on first LCD  15 . 
     That is, the call is continued until when the state of mobile communication terminal  1  is changed to the open state or until when the on-hook key is depressed. In the case where the other party has disconnected the line during the call, the process may proceed to step S 35 , as in the case where the off-hook key has been depressed in step S 34 . 
     In step S 31 , the terminal goes on-hook. Specifically, radio circuit  22  is caused to disconnect the line that has been connected for telephone conversation. The terminal goes on-hook when mobile communication terminal  1  that was in the closed state during the call is changed to the open state. This allows the user to end the call with a simple operation of changing the state of mobile communication terminal  1  from the closed state to the open state. 
     In step S 32 , the first display screen stored in EEPROM  33  in step S 26  is displayed on first LCD  15 , and in the following step S 33 , the second display screen stored in EEPROM  33  in step S 27  is displayed on second LCD  16 . The process is then terminated. In this manner, the screens that were being displayed on first LCD  15  and second LCD  16  before the call are displayed again, allowing the user to resume the job that the user was doing before the call. 
     If it is determined in step S 34  that the on-hook key has been depressed, in step S 35 , the terminal goes on-hook. Specifically, radio circuit  22  is caused to disconnect the line that has been connected for telephone conversation. The user can end the call by depressing the on-hook key, without the need of changing the state of mobile communication terminal  1  from the closed state to the open state. 
     In step S 36 , it is determined whether the open state has been detected as the state of mobile communication terminal  1 . In other words, it is determined whether the state of mobile communication terminal  1  has been changed from the closed state to the open state. Specifically, it is determined whether open-state sensor  23  has changed from OFF to ON. The process waits until the open state is detected (NO in step S 36 ), and once the open state is detected (YES in step S 36 ), the process proceeds to step S 32 . 
     On the other hand, if mobile communication terminal  1  is in the closed state upon detection of an incoming call in step S 21  (NO in step S 22 ), in step S 39 , an incoming call alert screen is displayed on first LCD  15 . The incoming call alert screen includes the message “incoming call” and the caller&#39;s telephone number. 
     In the following step S 40 , it is determined whether an off-hook key has been depressed. If the off-hook key has been depressed, the process proceeds to step S 41 ; otherwise, the process proceeds to step S 45 . The off-hook key may be a hard key arranged on housing portion  5 , or a soft key displayed on first LCD  15 . That is, while radio circuit  22  is receiving an incoming call, the process waits until the off-hook key is depressed, and the process proceeds to step S 41  when the off-hook key is depressed. 
     In step S 45 , it is determined whether the calling is continued. If the calling is continued, the process returns to step S 40 ; otherwise, the process proceeds to step S 46 . In step S 46 , as in step S 38 , the screen notifying of the incoming call history is displayed on first LCD  15 , and the process is terminated. 
     In step S 41 , radio circuit  22  is caused to take the terminal off-hook. As a result, the line is connected to enable conversation. A conversation process is performed over the connected line (step S 42 ). When the off-hook key is depressed, the terminal goes off-hook, even though the state of mobile communication terminal  1  is not changed from the open state to the closed state, so that the conversation can be started. 
     In step S 43 , it is determined whether the on-hook key has been depressed. If the on-hook key has been depressed, the process proceeds to step S 44 ; otherwise, the process returns to step S 42 . In the case where the other party has disconnected the line during the call, the process may proceed to step S 44 , as in the case where the on-hook key has been depressed in step S 43 . In the following step S 44 , the terminal goes on-hook. Specifically, radio circuit  22  is caused to disconnect the line that has been connected for the telephone conversation, and the process is terminated. 
     For example in the case where there is an incoming call while the user is causing mobile communication terminal  1  to execute an application program, the user may change mobile communication terminal  1  to the closed state so as to start the conversation. After an end of the conversation, when the user performs an operation of changing the state of mobile communication terminal  1  to the open state, the screens that were being displayed on first LCD  15  and second LCD  16  before the call are displayed on first LCD  15  and second LCD  16 , respectively. This allows the user to resume the suspended application program. 
     As described above, according to mobile communication terminal  1  of the present embodiment, in the case where a telephone number of a call destination is accepted while the open state is being detected and when the closed state is detected after the telephone number has been accepted, a call is originated to the accepted telephone number. This allows the user to originate a call with a simple operation of changing the state of mobile communication terminal  1  from the open state to the closed state. 
     In the open state, mobile communication terminal  1  displays on second LCD  16  the related information that is related to the user identification information that has been selected from the list screen of the user identification information displayed on first LCD  15 . This facilitates selection of the call destination. 
     When an incoming call is detected in the open state, mobile communication terminal  1  goes off-hook in response to an event that the closed state is detected. This allows the user to take the terminal off-hook with a simple operation of changing its state from the open state to the closed state. 
     It should be understood that the embodiments disclosed herein are illustrative and non-restrictive in every respect. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.