Abstract:
A display method for a terminal includes displaying simultaneously, on a single display, a plurality of screens in a corresponding plurality of spatially different directions. The method further includes displaying an item on a first screen of the plurality of screens, receiving user input at the terminal with regard to the item, and displaying item information on a second screen of the plurality of screens responsive to the receiving of the user input, such that the item information includes information relating to the item.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    Pursuant to 35 U.S.C. §119(a), this application claims the benefit of earlier filing date and right of priority to Korean Application Nos. 10-2009-0042741, filed on May 15, 2009, 10-2009-0045054, filed on May 22, 2009, and 10-2009-0069016, filed on Jul. 28, 2009, the contents of which are hereby incorporated by reference herein in their entirety 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to a mobile terminal equipped with a multi-view display capable of providing a plurality of screens at the same time by displaying the screens in different directions and a method of controlling the mobile terminal. 
         [0004]    2. Description of the Related Art 
         [0005]    Mobile terminals are portable devices, which can provide users with various services such as a voice calling service, a video calling service, an information input/output service, and a data storage service. 
         [0006]    As the types of services provided by mobile terminals diversify, an increasing number of mobile terminals have been equipped with various complicated functions such as capturing photos or moving pictures, playing music files or moving image files, providing game programs, receiving broadcast programs and providing wireless internet services and have thus evolved into multimedia players. 
         [0007]    Various attempts have been made to realize such complicated functions as hardware devices or software programs. For example, various user interface (UI) environments, in which users are allowed to easily search for and choose desired functions, have been developed. In addition, the demand for various designs for mobile terminals such as a double-sided liquid crystal display (LCD) or a full touch screen has steadily grown due to a growing tendency of considering mobile terminals as personal items that can represent personal individuality. 
         [0008]    However, there is a restriction in allocating sufficient space for a UI (such as a display device) of a mobile terminal without compromising the mobility and the portability of a mobile terminal. Therefore, for an efficient use of various functions provided by a mobile terminal, it is necessary to develop ways to effectively control the operation of a mobile terminal using a new data input/output method and using a multi-view display capable of providing a plurality of screens at the same time by displaying the screens in different display directions. 
       SUMMARY OF THE INVENTION 
       [0009]    The present invention provides a mobile terminal equipped with a multi-view display capable of providing a plurality of screens at the same time by displaying the screens in different display directions and a method of controlling the mobile terminal. 
         [0010]    According to an aspect of the present invention, there is provided a method of controlling a mobile terminal, the method including providing a display module capable of providing a plurality of screens at the same time by displaying the screens in different display directions and displaying a first preview image provided by a camera on the display module in a first display direction when the display module is held in its initial position; if the display module is rotated in a first direction from its initial position by a predetermined amount, displaying a second preview image provided by the camera on the display module in a second display direction; and if the display module is rotated in a second direction from its initial position by the predetermined amount, displaying a third preview image provided by the camera on the display module in a third display direction. 
         [0011]    According to another aspect of the present invention, there is provided a mobile terminal including a camera; a display module configured to be capable of providing a plurality of screens at the same time by displaying the screens in different display directions; a sensing unit configured to sense the motion of the display module and output the results of the sensing; and a controller configured to display a first preview image provided by the camera on the display module in a first display direction when the display module is held in its initial position and to display a second preview image provided by the camera on the display module in a second display direction if the results of the sensing performed by the motion sensor indicates that the display module has been rotated in a first direction from its initial position by a predetermined amount. 
         [0012]    According to another aspect of the present invention, there is provided a method of controlling a mobile terminal, the method including providing a display module capable of providing a plurality of screens at the same time by displaying the screens in different display directions, and displaying first through third operation screens on the display module in first through third display directions, respectively; receiving a user input through one of the first through third operation screens; and selecting one of the first through third operation screens based on a relative location of a user to the display module and performing an operation corresponding to the received user input on the selected operation screen. 
         [0013]    According to another aspect of the present invention, there is provided a mobile terminal including a display module configured to be capable of providing a plurality of screens at the same time by displaying the screens in different display directions; a sensing unit configured to sense a relative position of a user to the display module; and a controller configured to display first through third operation screens on the display module in first through third display directions, respectively, wherein, if a user input is received through the display module, the controller selects one of the first through third operation screens based on a relative location of a user to the display module and performs an operation corresponding to the received user input on the selected operation screen. 
         [0014]    According to another aspect of the present invention, there is provided a method of controlling a mobile terminal, the method including providing a display module capable of providing a plurality of screens at the same time by displaying the screens in different display directions, connecting a video conference call; and displaying images of first through third participants in the video conference call on the display module in first through third display directions, respectively. 
         [0015]    According to another aspect of the present invention, there is provided a mobile terminal including a wireless communication unit configured to connect a call; a display module configured to be capable of providing a plurality of screens at the same time by displaying the screens in different display directions; and a controller configured to connect a video conference call via the wireless communication unit and display images of first through third participants in the video conference call on the display module in first through third display directions, respectively. 
         [0016]    According to another aspect of the present invention, there is provided a method of controlling a mobile terminal, the method including providing a display module capable of providing a plurality of screens at the same time by displaying the screens in different display directions; receiving a broadcast signal; and displaying first through third broadcast screens obtained by demodulating the broadcast signal on the display module in first through third display directions, respectively. 
         [0017]    According to another aspect of the present invention, there is provided a mobile terminal including a broadcast reception module configured to receive a broadcast signal; a display module configured to be capable of providing a plurality of screens at the same time by displaying the screens in different display directions; and a controller configured to display first through third broadcast screens obtained by demodulating the broadcast signal on the display module in first through third display directions, respectively. 
         [0018]    According to another aspect of the present invention, there is provided a method of controlling a mobile terminal, the method including providing a display module capable of providing a plurality of screens at the same time by displaying the screens in different display directions; selecting an operating mode; displaying a first screen corresponding to the selected operating mode on the display module in a first display direction; and displaying second and third screens corresponding to the selected operating mode on the display module in second and third display directions, respectively. 
         [0019]    According to another aspect of the present invention, there is provided a mobile terminal including a display module configured to be capable of providing a plurality of screens at the same time by displaying the screens in different display directions; and a controller configured to select an operating mode and display first through third screens corresponding to the selected operating mode on the display module in first through third display directions, respectively. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0020]    The above and other features and advantages of the present invention will become more apparent by describing in detail preferred embodiments thereof with reference to the attached drawings in which: 
           [0021]      FIG. 1  illustrates a block diagram of a mobile terminal according to an exemplary embodiment of the present invention; 
           [0022]      FIG. 2  illustrates a front perspective view of the mobile terminal shown in  FIG. 1 ; 
           [0023]      FIG. 3  illustrates a rear perspective view of the mobile terminal shown in  FIG. 1 ; 
           [0024]      FIGS. 4 and 5  illustrate diagrams for explaining the structure and operation of a multi-view display that can be used in the mobile terminal shown in  FIG. 1 ; 
           [0025]      FIG. 6  illustrates a flowchart of a method of controlling a mobile terminal according to a first exemplary embodiment of the present invention; 
           [0026]      FIG. 7  illustrates a flowchart of a method of controlling a mobile terminal according to a second exemplary embodiment of the present invention; 
           [0027]      FIG. 8  illustrates a flowchart of a method of controlling a mobile terminal according to a third exemplary embodiment of the present invention; 
           [0028]      FIG. 9  illustrates a flowchart of a method of controlling a mobile terminal according to a fourth exemplary embodiment of the present invention; 
           [0029]      FIG. 10  illustrates a flowchart of a method of controlling a mobile terminal according to a fifth exemplary embodiment of the present invention; 
           [0030]      FIGS. 11 through 14  illustrate diagrams of various screens that can be displayed by a multi-view display; 
           [0031]      FIGS. 15 and 16  illustrate how to control the mobile terminal shown in  FIG. 1  in a three-dimensional (3D) camera shooting mode; 
           [0032]      FIGS. 17 through 19  illustrate how to select and execute one of a plurality of objects displayed on a screen; 
           [0033]      FIGS. 20 through 23  illustrate how to control the mobile terminal shown in  FIG. 1  in a 3D video call mode; 
           [0034]      FIG. 24  illustrates how to control the mobile terminal shown in  FIG. 1  in a 3D broadcast viewer mode; and 
           [0035]      FIGS. 25 through 33  illustrate how to control the mobile terminal shown in  FIG. 1  in other various operating modes. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0036]    The present invention will hereinafter be described in detail with reference to the accompanying drawings in which exemplary embodiments of the invention are shown. 
         [0037]    The term ‘mobile terminal’, as used herein, may indicate a mobile phone, a smart phone, a laptop computer, a digital broadcast receiver, a personal digital assistant (PDA), a portable multimedia player (PMP), or a navigation device. In this disclosure, the terms ‘module’ and ‘unit’ can be used interchangeably. 
         [0038]      FIG. 1  illustrates a block diagram of a mobile terminal  100  according to an embodiment of the present invention. Referring to  FIG. 1 , the mobile terminal  100  may include a wireless communication unit  110 , an audio/video (A/V) input unit  120 , a user input unit  130 , a sensing unit  140 , an output unit  150 , a memory  160 , an interface unit  170 , a controller  180 , and a power supply unit  190 . Two or more of the wireless communication unit  110 , the A/V input unit  120 , the user input unit  130 , the sensing unit  140 , the output unit  150 , the memory  160 , the interface unit  170 , the controller  180 , and the power supply unit  190  may be incorporated into a single unit, or some of the wireless communication unit  110 , the A/V input unit  120 , the user input unit  130 , the sensing unit  140 , the output unit  150 , the memory  160 , the interface unit  170 , the controller  180 , and the power supply unit  190  may be divided into two or more smaller units. 
         [0039]    The wireless communication unit  110  may include a broadcast reception module  111 , a mobile communication module  113 , a wireless internet module  115 , a short-range communication module  117 , and a global positioning system (GPS) module  119 . 
         [0040]    The broadcast reception module  111  may receive a broadcast signal and/or broadcast-related information from an external broadcast management server through a broadcast channel. The broadcast channel may be a satellite channel or a terrestrial channel. The broadcast management server may be a server which generates broadcast signals and/or broadcast-related information and transmits the generated broadcast signals and/or the generated broadcast-related information or may be a server which receives and then transmits previously-generated broadcast signals and/or previously-generated broadcast-related information. 
         [0041]    The broadcast-related information may include broadcast channel information, broadcast program information and/or broadcast service provider information. The broadcast signal may be a TV broadcast signal, a radio broadcast signal, a data broadcast signal, the combination of a data broadcast signal and a TV broadcast signal or the combination of a data broadcast signal and a radio broadcast signal. The broadcast-related information may be provided to the mobile terminal  100  through a mobile communication network. In this case, the broadcast-related information may be received by the mobile communication module  113 , rather than by the broadcast reception module  111 . The broadcast-related information may come in various forms. For example, the broadcast-related information may be electronic program guide (EPG) of digital multimedia broadcasting (DMB) or may be electronic service guide (ESG) of digital video broadcast-handheld (DVB-H). 
         [0042]    The broadcast reception module  111  may receive the broadcast signal using various broadcasting systems such as digital multimedia broadcasting-terrestrial (DMB-T), digital multimedia broadcasting-satellite (DMB-S), media forward link only (MediaFLO), DVB-H, and integrated services digital broadcast-terrestrial (ISDB-T). In addition, the broadcast reception module  111  may be configured to be suitable for nearly all types of broadcasting systems other than those set forth herein. The broadcast signal and/or the broadcast-related information received by the broadcast reception module  111  may be stored in the memory  160 . 
         [0043]    The mobile communication module  113  may transmit wireless signals to or receives wireless signals from at least one of a base station, an external terminal, and a server through a mobile communication network. The wireless signals may include various types of data according to whether the mobile terminal  100  transmits/receives voice call signals, video call signals, or text/multimedia messages. 
         [0044]    The wireless internet module  115  may be a module for wirelessly accessing the internet. The wireless internet module  115  may be embedded in the mobile terminal  100  or may be installed in an external device. The wireless internet module  115  may be embedded in the mobile terminal  100  or may be installed in an external device. The wireless internet module  115  may use various wireless internet technologies such as wireless local area network (WLAN), Wireless Broadband (WiBro), World Interoperability for Microwave Access (Wimax), and High Speed Downlink Packet Access (HSDPA). 
         [0045]    The short-range communication module  117  may be a module for short-range communication. The short-range communication module  117  may use various short-range communication techniques such as Bluetooth, radio frequency identification (RFID), infrared data association (IrDA), ultra wideband (UWB), and ZigBee. 
         [0046]    The GPS module  119  may receive position information from a plurality of GPS satellites. The A/V input unit  120  may be used to receive audio signals or video signals. The A/V input unit  120  may include a camera  121  and a microphone  123 . The camera  121  may process various image frames such as still images or moving images captured by an image sensor in a video call mode or an image capturing mode. The image frames processed by the camera  121  may be displayed by a display module  151 . 
         [0047]    The image frames processed by the camera  121  may be stored in the memory  160  or may be transmitted to an external device through the wireless communication unit  110 . The mobile terminal  100  may include two or more cameras  121 . 
         [0048]    The microphone  123  may receive external sound signals during a call mode, a recording mode, or a voice recognition mode with the use of a microphone and may convert the sound signals into electrical sound data. In the call mode, the mobile communication module  113  may convert the electrical sound data into data that can be readily transmitted to a mobile communication base station and then output the data obtained by the conversion. The microphone  123  may use various noise removal algorithms to remove noise that may be generated during the reception of external sound signals. 
         [0049]    The user input unit  130  may generate key input data based on user input for controlling the operation of the mobile terminal  100 . The user input unit  130  may be implemented as a keypad, a dome switch, a touch pad (static pressure/static voltage), a jog wheel, or a jog switch. In particular, if the user input unit  130  is implemented as a touch pad and forms a layer structure together with the display module  151 , the user input unit  130  and the display module  151  may be collectively referred to as a touch screen. 
         [0050]    The sensing unit  140  determines a current state of the mobile terminal  100  such as whether the mobile terminal  100  is opened up or closed, the position of the mobile terminal  100  and whether the mobile terminal  100  is placed in contact with a user, and generates a sensing signal for controlling the operation of the mobile terminal  100 . For example, when the mobile terminal  100  is a slider-type mobile phone, the sensing unit  140  may determine whether the mobile terminal  100  is opened up or closed. In addition, the sensing unit  140  may determine whether the mobile terminal  100  is powered by the power supply unit  190  and whether the interface unit  170  is connected to an external device. 
         [0051]    The sensing unit  140  may include a proximity sensor  141 , a pressure sensor  143  and a motion sensor  145 . The proximity sensor  141  may detect the existence of an object nearby without any mechanical contact by detecting a variation in an alternating magnetic field or a static magnetic field or a variation in static capacitance. The sensing unit  140  may include two or more proximity sensors  141 . 
         [0052]    The pressure sensor  143  may determine whether pressure is being applied to the mobile terminal  100  or may measure the level of pressure, if any, applied to the mobile terminal  100 . The pressure sensor  143  may be installed in a certain part of the mobile terminal  100  where the detection of pressure is necessary. For example, the pressure sensor  143  may be installed in the display module  151 . In this case, it is possible to differentiate a typical touch input from a pressure touch input, which is generated using a higher pressure level than that used to generate a typical touch input, based on data provided by the pressure sensor  143 . In addition, when a pressure touch input is detected from the display module  151 , it is possible to determine the level of pressure applied to the display module  151  upon the detection of a pressure touch input based on data provided by the pressure sensor  143 . 
         [0053]    The motion sensor  145  may determine the location of the mobile terminal  100  or may sense the movement of the mobile terminal  100 . An acceleration sensor or a gyro-sensor may be used as the motion sensor  145 . 
         [0054]    Acceleration sensors are a type of device for converting an acceleration variation into an electric signal. With recent developments in micro-electromechanical system (MEMS) technology, acceleration sensors have been widely used in various products for various purposes. For example, an acceleration sensor may be installed in an airbag system for an automobile and may thus be used to detect collisions. Alternatively, an acceleration sensor may be used as an input device for a computer game and may sense the motion of the human hand during a computer game. Two or three acceleration sensors  145  representing different axial directions may be installed in the mobile terminal  100 . Alternatively, only one acceleration sensor  145  representing a Z axis may be installed in the mobile terminal  100 . 
         [0055]    Gyro-sensors are sensors measuring angular velocity and are thus able to determine the deviation of the direction of an object from a reference direction. 
         [0056]    The output unit  150  may output an audio signal, a video signal and an alarm signal. The output unit  150  may include the display module  151 , and an audio output module  153 , an alarm module  155  and a haptic module  157 . 
         [0057]    The display module  151  may display various information processed by the mobile terminal  100 . For example, if the mobile terminal  100  is in a call mode, the display module  151  may display a user interface (UI) or a graphic user interface (GUI) for making or receiving a call. If the mobile terminal  100  is in a video call mode or an image capturing mode, the display module  151  may display a UI or a GUI for capturing or receiving images. 
         [0058]    If the display module  151  and the user input unit  130  form a layer structure together and are thus implemented as a touch screen, the display module  151  may be used as both an output device and an input device. If the display module  151  is implemented as a touch screen, the display module  151  may also include a touch screen panel and a touch screen panel controller. The touch screen panel may be a transparent panel attached onto the exterior of the mobile terminal  100  and may be connected to an internal bus of the mobile terminal  100 . The touch screen panel may keep monitoring whether the touch screen panel is being touched by the user. Once there is touch input detected from the touch screen panel, the touch screen panel may transmit a number of signals corresponding to the detected touch input to the touch screen panel controller. The touch screen panel controller may process the signals transmitted by the touch screen panel, and may transmit the processed signals to the controller  180 . Then, the controller  180  may determine whether a touch input has been generated and which part of the touch screen panel has been touched based on the processed signals transmitted by the touch screen panel controller. 
         [0059]    The display module  151  may include electronic paper (e-paper). E-paper is a type of reflective display technology and can provide as high resolution as ordinary ink on paper, wide viewing angles, and excellent visual properties. E-paper can be implemented on various types of substrates such as a plastic, metallic or paper substrate and can display and maintain an image thereon even after power is cut off. In addition, e-paper can reduce the power consumption of the mobile terminal  100  because it does not require a backlight assembly. The display module  151  may be implemented as e-paper by using electrostatic-charged hemispherical twist balls, using electrophoretic deposition, or using microcapsules. 
         [0060]    The display module  151  may include at least one of a liquid crystal display (LCD), a thin film transistor (TFT)-LCD, an organic light-emitting diode (OLED), a flexible display, a three-dimensional (3D) display and a transparent display. The mobile terminal  100  may include two or more display modules  151 . For example, the mobile terminal  100  may include an external display module (not shown) and an internal display module (not shown). 
         [0061]    The audio output module  153  may output audio data received by the wireless communication unit  110  during a call reception mode, a call mode, a recording mode, a voice recognition mode, or a broadcast reception mode or may output audio data present in the memory  160 . In addition, the audio output module  153  may output various sound signals associated with the functions of the mobile terminal  100  such as receiving a call or a message. The audio output module  153  may include a speaker and a buzzer. 
         [0062]    The alarm module  155  may output an alarm signal indicating the occurrence of an event in the mobile terminal  100 . Examples of the event include receiving a call signal, receiving a message, and receiving a key signal. Examples of the alarm signal output by the alarm module  155  include an audio signal, a video signal and a vibration signal. More specifically, the alarm module  155  may output an alarm signal upon receiving a call signal or a message. In addition, the alarm module  155  may receive a key signal and may output an alarm signal as feedback to the key signal. Therefore, the user may be able to easily recognize the occurrence of an event based on an alarm signal output by the alarm module  155 . Not only the alarm module  155  but also the display module  151  and the audio output module  153  may output an alarm signal in order to alert the user to the occurrence of an event. 
         [0063]    The haptic module  157  may provide various haptic effects (such as vibrations) that can be perceived by the user. If the haptic module  157  generates vibration as a haptic effect, the intensity and the pattern of vibration generated by the haptic module  157  may be altered in various manners. The haptic module  157  may synthesize different vibration effects and may output the result of the synthesization. Alternatively, the haptic module  157  may sequentially output different vibration effects. 
         [0064]    The haptic module  157  may provide various haptic effects, other than vibration, such as a haptic effect obtained using a pin array that moves perpendicularly to a contact skin surface, a haptic effect obtained by injecting or sucking in air through an injection hole or a suction hole, a haptic effect obtained by giving a stimulus to the surface of the skin, a haptic effect obtained through contact with an electrode, a haptic effect obtained using an electrostatic force, and a haptic effect obtained by realizing the sense of heat or cold using a device capable of absorbing heat or generating heat. The haptic module  157  may be configured to enable the user to recognize a haptic effect using the kinesthetic sense of the fingers or the arms. The mobile terminal  100  may include two or more haptic modules  157 . 
         [0065]    The memory  160  may store various programs necessary for the operation of the controller  180 . In addition, the memory  160  may temporarily store various data such as a phonebook, messages, still images, or moving images. 
         [0066]    The memory  160  may include at least one of a flash memory type storage medium, a hard disk type storage medium, a multimedia card micro type storage medium, a card type memory (e.g., a secure digital (SD) or extreme digital (XD) memory), a random access memory (RAM), and a read-only memory (ROM). The mobile terminal  100  may operate a web storage, which performs the functions of the memory  160  on the internet. 
         [0067]    The interface unit  170  may interface with an external device that can be connected to the mobile terminal  100 . The interface unit  170  may be a wired/wireless headset, an external battery charger, a wired/wireless data port, a card socket for, for example, a memory card, a subscriber identification module (SIM) card or a user identity module (UIM) card, an audio input/output (I/O) terminal, a video I/O terminal, or an earphone. The interface unit  170  may receive data from an external device or may be powered by an external device. The interface unit  170  may transmit data provided by an external device to other components in the mobile terminal  100  or may transmit data provided by other components in the mobile terminal  100  to an external device. 
         [0068]    When the mobile terminal  100  is connected to an external cradle, the interface unit  170  may provide a path for supplying power from the external cradle to the mobile terminal  100  or for transmitting various signals from the external cradle to the mobile terminal  100 . 
         [0069]    The controller  180  may control the general operation of the mobile terminal  100 . For example, the controller  180  may perform various control operations regarding making/receiving a voice call, transmitting/receiving data, or making/receiving a video call. The controller  180  may include a multimedia play module  181 , which plays multimedia data. The multimedia play module  181  may be implemented as a hardware device and may be installed in the controller  180 . Alternatively, the multimedia play module  181  may be implemented as a software program. 
         [0070]    The power supply unit  190  may be supplied with power by an external power source or an internal power source and may supply power to the other components in the mobile terminal  100 . 
         [0071]    The mobile terminal  100  may include a wired/wireless communication system or a satellite communication system and may thus be able to operate in a communication system capable of transmitting data in units of frames or packets. 
         [0072]    The exterior of the mobile terminal  100  will hereinafter be described in detail with reference to  FIGS. 2 and 3 . For convenience, assume that the mobile terminal  100  is a slider-type mobile terminal equipped with a touch screen. However, the present invention is not restricted to a slider-type mobile terminal. Rather, the present invention can be applied to various types of mobile phones, other than a slider-type mobile terminal. 
         [0073]      FIG. 2  illustrates a front perspective view of the mobile terminal  100  shown in  FIG. 1 . Referring to  FIG. 2 , the mobile terminal  100  may include a first body  100 A and a second body  100 B. The first and second bodies  100 A and  100 B may be configured to be able to slide up and down against each other. 
         [0074]    When the first body  100 A and the second body  100 B completely overlap each other, the mobile terminal  100  is referred to as being closed. On the other hand, when the first body  100 A is slid up against the second body  100 B and thus the front of the second body  100 B is partially exposed, as shown in  FIG. 2 , the mobile terminal  100  is referred to as being open. 
         [0075]    When the mobile terminal  100  is closed, the mobile terminal may generally operate in a standby mode and may be released from the standby mode in response to user manipulation. On the other hand, when the mobile terminal  100  is open, the mobile terminal  100  may generally operate in a call mode and may be switched to the standby mode either manually in response to user manipulation or automatically after the lapse of a predefined amount of time. 
         [0076]    Referring to  FIG. 2 , the exterior of the first body  100 A may be defined by a first front case  100 A- 1  and a first rear case  100 A- 2 . Various electronic devices may be installed in the space formed by the first front case  100 A- 1  and the first rear case  100 A- 2 . At least one intermediate case may be additionally provided between the first front case  100 A- 1  and the first rear case  100 A- 2 . The first front case  100 A- 1  and the first rear case  100 A- 2  may be formed of a synthetic resin through injection molding. Alternatively, the first front case  100 A- 1  and the first rear case  100 A- 2  may be formed of a metal such as stainless steel (STS) or titanium (Ti). 
         [0077]    The display module  151 , a first audio output module  153   a , a first camera  121   a  and a first user input unit  130   a  may be provided in the first front case  100 A- 1 . 
         [0078]    Examples of the display module  151  include an LCD and an OLED which can visualize information. Since a touch pad is configured to overlap the display module  151  and thus to form a layer structure, the display module  151  may serve as touch screens. Thus, it is possible to input various information to the mobile terminal  100  simply by touching the display module  151 . 
         [0079]    The first audio output module  153   a  may be implemented as a receiver or a speaker. The first camera  121   a  may be configured to capture a still image or a moving image of the user. 
         [0080]    The exterior of the second body  100 B may be defined by a second front case  100 B- 1  and a second rear case  100 B- 2 . A second user input unit  130   b  may be disposed in the second body  100 B, and particularly, at the front of the second front case  100 B- 1 . Third and fourth user input units  130   c  and  130   d , the microphone  123  and the interface unit  170  may be provided in the second front case  100 B- 1  or the second rear case  100 B- 2 . 
         [0081]    The first through fourth user input units  130   a  through  130   d  may be collectively referred to as the user input unit  130 . The user input unit  130  may adopt various manipulation methods as long as it can offer tactile feedback to the user. 
         [0082]    For example, the user input unit  130  may be implemented as a dome switch or a touch pad which receives a command or information upon being pushed or touched by the user. Alternatively, the user input unit  130  may be implemented as a wheel, a jog dial, or a joystick. 
         [0083]    The first user input unit  130   a  may allow the user to input various commands such as ‘start’, ‘end’, and ‘scroll’ to the mobile terminal  100 , the second user input unit  130   b  may be used to input various numerals, characters or symbols, and the third and fourth user input units  130   c  and  130   d  may be used as hot keys for activating certain functions of the mobile terminal  100 . 
         [0084]    The microphone  123  may be configured to be able to properly receive the voice of the user or other sounds. 
         [0085]    The interface unit  170  may serve as a path for allowing the mobile terminal  100  to exchange data with an external device. For example, the interface unit  170  may be a connector for connecting an earphone to the mobile terminal  100  in an either wired or wireless manner, a port for short-range communication or a power supply port for supplying power to the mobile terminal  100 . The interface unit  170  may be a card socket for accommodating an exterior card such as a SIM or UIM card or a memory card. 
         [0086]      FIG. 3  illustrates a rear perspective view of the mobile terminal  100  shown in  FIG. 2 . Referring to  FIG. 3 , a fifth user input unit  130   e  and the second camera  121   b  may be disposed at the rear of the second rear case  100 B- 2  of the second body  100 B, and a sixth user input unit  130   f  may be disposed on one side of the second body  100 B. 
         [0087]    The second camera  121   b  may have a different photographing direction from that of the first camera  121   a  shown in  FIG. 2 . In addition, the first and second cameras  121   a  and  121   b  may have different resolutions. For example, the first camera  121   a  may be used to capture and then transmit an image of the face of the user during a video call. Thus, a low-resolution camera may be used as the first camera  121   a . The second camera  121   b  may be used to capture an image of an ordinary subject. In this case, the image captured by the second camera  121   b  may not need to be transmitted. Thus, a high-resolution camera may be used as the second camera  121   b.    
         [0088]    A cameral flash  125  and a mirror  126  may be disposed near the second camera  121   b . The cameral flash  125  may be used to illuminate a subject when the user attempts to capture an image of the subject with the second camera  121   b . The mirror  126  may be used for the user to prepare him- or herself for taking a self shot. 
         [0089]    A second audio output module (not shown) may be additionally provided in the second rear case  100 B- 2 . The second audio output module may realize a stereo function along with the first audio output module  153   a . The second audio output module may also be used in a speaker-phone mode. 
         [0090]    An antenna (not shown) for receiving a broadcast signal may be disposed on one side of the second rear case  100 B- 2 . The antenna may be installed so as to be able to be pulled out of the second rear case  100 B- 2 . 
         [0091]    A slide module  100 C may be partially exposed on the first rear case  100 A- 2  of the first body  100 A. The slide module  100 C may couple the first body  100 A and the second body  100 B such that the first body  100 A and the second body  100 B can slide up and down against each other. A portion of the slide module  100 C may be hidden from view by the second front case  100 B- 1  of the second body  100 B, and thus may not be exposed. 
         [0092]    The second camera  121   b  and the other elements that have been described as being provided on the rear case  100 A- 2  may be provided on the front case  100 A- 1 . In addition, the first camera  121   a  may be configured to be rotatable and thus to cover the photographing direction of the second camera  121   b . In this case, the second camera  121   b  may be optional. 
         [0093]    The power supply unit  190  may be disposed in the rear case  100 A- 2 . The power supply unit may be a rechargeable battery and may be coupled to the rear case  100 A- 2  so as to be attachable to or detachable from the rear case  100 A- 2 . 
         [0094]      FIGS. 4 and 5  illustrate diagrams for explaining the structure and operation of a multi-view display that can be used in the mobile terminal  100 . 
         [0095]    More specifically,  FIG. 4(   a ) illustrates a typical display. Referring to  FIG. 4(   a ), viewers  40 A,  40 B and  40 C can view the same screen from the typical display regardless of their different viewing angles. 
         [0096]      FIG. 4(   b ) illustrates a multi-view display that can provide three different screens for three different directions. Referring to  FIG. 4(   b ), the multi-view display may include a filter that restricts the viewing angle of the multi-view display on a pixel-by-pixel basis, and may thus allow viewers  41 A,  41 B and  41 C from left, front and right viewing zones b, a and c, respectively, to view different screens therefrom. 
         [0097]      FIG. 5  illustrates the structure of the multi-view display shown in  FIG. 4(   b ). Referring to  FIG. 5 , the multi-view display may include a lower substrate  10 , an upper substrate  30  and a liquid crystal layer  18  interposed between the lower substrate  10  and the upper substrate  30 . The upper substrate  30  may include a mask filter  22 , a plurality of light-shield walls  13  and a color filter array  28 . A plurality of light-shield portions  21  and a plurality of light-transmission portions  23  may be alternately arranged in the mask filter  22 . 
         [0098]    When the multi-view display is viewed from the front viewing zone a of  FIG. 4(   b ), the light-shield portions  21  may shield light emitted from second pixel regions P 2  and third pixel regions P 3 , and the light-transmission portions  23  may allow light emitted from first pixel regions P 1  to pass through the mask filter  22 . As a result, an image displayed in first pixel regions P 1  can appear visible in a first display direction {circle around ( 1 )}. 
         [0099]    On the other hand, when the multi-view display is viewed from the left viewing zone b of  FIG. 4(   b ), the light-shield portions  21  may shield light emitted from the first pixel regions P 1  and the third pixel regions P 3 , and the light-transmission portions  23  may allow light emitted from the second pixel regions P 2  to pass through the mask filter  22 . As a result, an image displayed in the second pixel regions P 2  can appear visible in a second display direction {circle around ( 2 )}. 
         [0100]    On the other hand, when the multi-view display is viewed from the right viewing zone c of  FIG. 4(   b ), the light-shield portions  21  may shield light emitted from the first pixel regions P 1  and the second pixel regions P 2 , and the light-transmission portions  23  may allow light emitted from the third pixel regions P 3  to pass through the mask filter  22 . As a result, an image displayed in the third pixel regions P 3  can appear visible in a third display direction {circle around ( 3 )}. 
         [0101]    In this manner, the multi-view display may be able to provide three different images for three different display directions, i.e., the first through third display directions {circle around ( 1 )}, {circle around ( 2 )} and {circle around ( 3 )}. However, the present invention is not restricted to this. That is, the multi-view display may be configured to be able to provide more than three screens for more than three different display directions. 
         [0102]      FIG. 6  illustrates a flowchart of a method of controlling a mobile terminal according to a first exemplary embodiment of the present invention. In the first exemplary embodiment, a multi-view display capable of providing a plurality of screens at the same time by displaying the screens in different display directions may be used as the display module  151 , and thus, the user may be able to view different screens from the display module  151  from different viewing angles. 
         [0103]    Referring to  FIG. 6 , if a 3D camera shooting mode is selected in response to, for example, a user command (S 200 ), the controller  180  may display a first preview image of a subject on the display module  151  in a first display direction (S 200 ). 
         [0104]    The first display direction may be a direction perpendicular to the surface of the display module  151 , and may corresponding to the front viewing zone a of  FIG. 4(   b ). When the display module  151  is held in its initial position, the first preview image may be displayed in the first display direction. 
         [0105]    The first preview image may be displayed along with a menu icon related to camera shooting and an icon indicating the operating state of the camera  121 . 
         [0106]    If the display module  151  maintains its initial position (S 210 ), the controller  180  may maintain the first preview image to be displayed in the first display direction (S 215 ). On the other hand, if measurement data provided by the motion sensor  145  indicates that the display module  151  has been rotated in a first direction (e.g., counterclockwise) from its initial position by more than a predetermined amount (S 220 ), the controller  180  may display a second preview image of the subject on the display module  151  in a second display direction (S 225 ). 
         [0107]    If the measurement data provided by the motion sensor  145  indicates that the display module  151  has been rotated in a second direction (e.g., clockwise) from its initial position by more than the predetermined amount (S 230 ), the controller  180  may display a third preview image of the subject on the display module  151  in a third display direction (S 235 ). 
         [0108]    The second display direction may be a direction obtained by rotating the display module  151  counterclockwise from the first display direction by a predetermined amount, and may correspond to the left viewing zone b of  FIG. 4(   b ). The third display direction may be a direction obtained by rotating the display module  151  clockwise from the first display direction by the predetermined amount, and may correspond to the right viewing zone c of  FIG. 4(   b ). Thus, the user may view a preview image of the right side or the left side of the subject simply by rotating the display module  151  clockwise or counterclockwise without the need to move from one position to another. 
         [0109]    Thereafter, if the user chooses to capture an image of the subject (S 240 ), the controller  180  may control the camera  121  to capture the first, second or third preview image (S 245 ). Data regarding the captured image may be stored in the memory  160 . The first through third preview images may be stored together in the memory  160 . Thus, if the user chooses to view a captured image of the subject, the captured first through third preview images may be displayed on the display module  151  at the same time. 
         [0110]    Operations  5210  through  5245  may be repeatedly performed until the user chooses to terminate the 3D camera shooting mode (S 250 ). 
         [0111]    In this manner, it is possible to view and capture the preview images of the front side, the left side and the right side of the subject simply by rotating the mobile terminal  100  without the need to move from one position to another. 
         [0112]      FIG. 7  illustrates a flowchart of a method of controlling a mobile terminal according to a second exemplary embodiment of the present invention. In the second exemplary embodiment, a multi-view display capable of providing a plurality of screens at the same time by displaying the screens in different display directions may be used as the display module  151 , and thus, the user may be able to view different screens from the display module  151  from different viewing angles. 
         [0113]    Referring to  FIG. 7 , if a 3D display mode is selected in response to, for example, a user command (S 260 ), the controller  180  may display first through third operation screens on the display module  151  in first through third display directions, respectively (S 265 ). The user may choose what operation screens to display in advance. 
         [0114]    If a user input is received through the display module  151  (S 270 ), the controller  180  may determine the relative position of the user to the mobile terminal  100  based on data provided by the motion sensor  145  regarding the motion of the display module  151  and data provided by an optical sensor regarding the slope of the display module  151  (S 275 ). 
         [0115]    Thereafter, the controller  180  may select one of the first through third operation screens based on the result of the determination performed in operation S 275  (S 280 ), and the controller  180  may perform an operation corresponding to the received user input on the selected operation screen (S 285 ). 
         [0116]    Operations S 265  through S 285  may be repeatedly performed until the user terminates the 3D display mode (S 290 ). 
         [0117]    In this manner, it is possible to perform a desired operation on any one of a plurality of screens displayed on the display module  151  simply by rotating the display module  151  without the need to manually navigate from one screen to another screen. 
         [0118]      FIG. 8  illustrates a flowchart of a method of controlling a mobile terminal according to a third exemplary embodiment of the present invention. In the third exemplary embodiment, like in the first and second exemplary embodiments, a multi-view display capable of providing a plurality of screens at the same time by displaying the screens in different display directions may be used as the display module  151 , and thus, the user may be able to view different screens from the display module  151  from different viewing angles. 
         [0119]    Referring to  FIG. 8 , if a 3D video call connection request is issued in response to, for example, a user command (S 300 ), the controller  180  may control the wireless communication unit  110  to connect a video conference call (S 305 ). 
         [0120]    Thereafter, the controller  180  may display the images of first through third participants in the video conference call on the display module  151  in first through third display directions, respectively (S 310 ). The first display direction may be a direction perpendicular to the surface of the display module  151 , and may correspond to the front viewing zone a of  FIG. 4(   b ). The second display direction may be a direction obtained by rotating the display module  151  counterclockwise from the first display direction by a predetermined amount, and may correspond to the left viewing zone b of  FIG. 4(   b ). The third display direction may be a direction obtained by rotating the display module  151  clockwise from the first display direction by the predetermined amount, and may correspond to the right viewing zone c of  FIG. 4(   b ). 
         [0121]    The controller  180  may display the image of the first participant at a normal frame rate and the images of the second and third participants at a frame rate lower than the normal frame rate (S 315 ). For example, the controller  180  may display the image of the first participant at  30  frames per second and the images of the second and third participants at  15  frames per second, thereby reducing the processing load. 
         [0122]    Thereafter, the controller  180  may determine whether the display module  151  has been rotated clockwise or counterclockwise, or whether the position of the user has changed (S 320 ). If it is determined in operation  5320  that the display module  151  has been rotated clockwise or counterclockwise, or that the position of the user has changed, the controller  180  may control the image of the first participant to be displayed at a higher frame rate than the images of the second and third participants (S 325 ). The controller  180  may determine whether the display module  151  has been rotated based on measurement data provided by the motion sensor  145 . In addition, the controller  180  may determine the relative position of the user to the mobile terminal  100  based on data provided by the motion sensor  145  regarding the motion of the display module  151  and data provided by an optical sensor regarding the slope of the display module  151 . 
         [0123]    If a video call-related function other than connecting a video call is selected (S 330 ), the controller  180  may control an operation corresponding to the selected function to be performed (S 335 ). 
         [0124]    Operations  5320  through  5335  may be repeatedly performed until the user chooses to terminate the video conference call (S 337 ). 
         [0125]    In this manner, it is possible to display the images of multiple participants in a video conference call at the same time on the display module  151  and to allow the user to selectively view each of the images of the multiple participants according to the location angle of the user. 
         [0126]      FIG. 9  illustrates a flowchart of a method of controlling a mobile terminal according to a fourth exemplary embodiment of the present invention. In the fourth exemplary embodiment, like in the first through third exemplary embodiments, a multi-view display capable of providing a plurality of screens at the same time by displaying the screens in different display directions may be used as the display module  151 , and thus, the user may be able to view different screens from the display module  151  from different viewing angles. 
         [0127]    Referring to  FIG. 9 , if a 3D broadcast viewer mode is selected in response to, for example, a user command (S 340 ), the controller  180  may receive a broadcast signal from a broadcast channel selected by the user (S 345 ), and may display first through third broadcast screens obtained by demodulating the received broadcast signal on the display module  151  in first through third display directions, respectively (S 350 ). The user may select what broadcast screens to display in advance. 
         [0128]    The controller  180  may display the first broadcast screen at a normal frame rate and the second and third broadcast screens at a frame rate lower than the normal frame rate in order to reduce the processing load. The controller  180  may output an audio signal corresponding to the first broadcast screen via the audio output module  157  and audio signals corresponding to the second and third broadcast screens via remote earphones such as a Bluetooth headset. 
         [0129]    If a user input is received through the display module  151  (S 355 ), the controller  180  may determine the relative position of the user to the mobile terminal  100  (S 360 ). More specifically, the controller  180  may determine the relative position of the user to the mobile terminal  100  based on based on data provided by the motion sensor  145  regarding the motion of the display module  151  and data provided by an optical sensor regarding the slope of the display module  151 . 
         [0130]    Thereafter, the controller  180  may select one of the first through third broadcast screens based on the result of the determination performed in operation  5360 , and may perform an operation corresponding to the received user input on the selected broadcast screen, e.g., the first broadcast screen (S 365 ). The controller  180  may change the frame rate at which each of the first through third broadcast screens is displayed according to the relative position of the user to the mobile terminal  100 . 
         [0131]    Operations S 345  through S 365  may be repeatedly performed until the user chooses to terminate the 3D broadcast viewer mode (S 367 ) 
         [0132]    In this manner, it is possible to selectively view and perform various operations on any one of a plurality of broadcast screens displayed on the display module  151  without the need to manually navigate from one broadcast screen to another broadcast screen. 
         [0133]      FIG. 10  illustrates a flowchart of a method of controlling a mobile terminal according to a fifth exemplary embodiment of the present invention. In the fifth exemplary embodiment, like in the first through fourth exemplary embodiments, a multi-view display capable of providing a plurality of screens at the same time by displaying the screens in different display directions may be used as the display module  151 , and thus, the user may be able to view different screens from the display module  151  from different viewing angles. 
         [0134]    Referring to  FIG. 10 , if an operating mode is selected in response to, for example, a user command (S 370 ), the controller  180  may display a first screen on the display module  151  in a first display direction (S 375 ). The controller  180  may display second and third screens on the display module  151  in second and third display directions, respectively (S 380 ). 
         [0135]    The first screen may be a main screen corresponding to the selected operating mode, and the second and third screens may be sub-screens corresponding to the selected operating mode. The first display direction may be a direction perpendicular to the surface of the display module  151 , and may correspond to the front viewing zone a of  FIG. 4(   b ). The second display direction may be a direction obtained by rotating the display module  151  counterclockwise from the first display direction by a predetermined amount, and may correspond to the left viewing zone b of  FIG. 4(   b ). The third display direction may be a direction obtained by rotating the display module  151  clockwise from the first display direction by the predetermined amount, and may correspond to the right viewing zone c of  FIG. 4(   b ). 
         [0136]    If the user chooses to switch screens (S 385 ), the controller  180  may change the display direction of the display module  151  (S 390 ) so as to switch between the first through third screens. More specifically, the controller  180  may switch between the first through third screens in response to the reception of a touch-and-drag input via the display module  151 , the tilting of the display module  151 , or the reception of a key input via the user input unit  130 . 
         [0137]    If a user input is received through the display module  151  (S 395 ), the controller  180  may determine the relative position of the user to the mobile terminal  100 , may select one of the first through third screens based on the result of the determination, and may perform an operation corresponding to the received user input on selected screen, e.g., the first screen (S 397 ). More specifically, the controller  180  may determine the relative position of the user to the mobile terminal  100  based on data provided by the motion sensor  145  regarding the motion of the display module  151  and data provided by an optical sensor regarding the slope of the display module  151 . 
         [0138]    Operations  5385  through  5397  may be repeatedly performed until the user selects another operating mode (S 399 ). 
         [0139]    In this manner, it is possible to perform various operations on any one of a plurality of screens displayed on the display module  151  by appropriately varying the viewing angle of the display module  151 . 
         [0140]    The first through fifth exemplary embodiments will hereinafter be described in further detail with reference to  FIGS. 11 through 33 . 
         [0141]      FIGS. 11 through 14  illustrate various screens that can be displayed by a multi-view display. Referring to  FIG. 11 , an image viewer screen  410  showing a first image, an image viewer screen  420  showing a second image and an image viewer screen  430  showing a third image may be displayed at the same time in first, second and third display directions, respectively. The display module  151  may provide a plurality of images at the same time by displaying the images in different display directions. Then, the user can view each of the images in a full-view mode simply by varying the viewing angle of the display module  151 . 
         [0142]      FIGS. 12 and 13  illustrate how to display a plurality of menu screens in different display directions. Referring to  FIG. 12 , a menu screen  440  showing a first list of menus, a menu screen  450  showing a second list of menus and a menu screen  460  showing a third list of menus may be displayed at the same time in first, second and third display directions, respectively. The menu screen  440  may be a main menu list, and the menu screens  450  and  460  may be sub-screens of the menu screen  440 . In this manner, it is possible to easily switch between the menu screens  440 ,  450  and  460  simply by varying the viewing angle of the display module  151 . 
         [0143]    Referring to  FIG. 13 , if the user touches and drags the menu screen  440  laterally, as indicated by reference numeral  443 , if the display module  151  is tilted to the left or to the right, or if a key input is received via the user input unit  130 , the controller  180  may switch from the menu screen  440  to the menu screen  450  or  460 . 
         [0144]      FIG. 14  illustrates how to display a plurality of screens representing different operating states at the same time on the display module  151  in different directions. Referring to  FIG. 14 , an idle screen  470  may be displayed in a first display direction, and a screen  480  indicating the existence of missed calls and a screen  490  indicating that the reception of messages may be displayed in second and third display directions, respectively. Thus, the user may easily identify events occurring in the mobile terminal  100  from the display module  151  simply by varying the viewing angle of the display module  151 . 
         [0145]    When using a multi-view display as the display module  151 , it is possible to easily identify various information from the display module  151  simply by varying the viewing angle of the display module  151  without the need to manually switch screens. For example, three or more calendar or scheduler screens can be displayed at the same time on a multi-view display, whereas only one calendar or scheduler screen (for example, a daily, weekly, monthly, and yearly calendar or scheduler screen) can be displayed at a time on a typical display. 
         [0146]    Various indicator icons indicating the operating state of a mobile terminal or representing additional information are generally displayed in a small size at the top of a display. On the other hand, when displayed on a multi-view display, the indicator icons can appear larger on a main screen, which is displayed on the multi-view display in a first display direction, than on a sub-screen, which is displayed on the multi-view display in a second or third display direction. Thus, it is possible to improve the efficiency of use of the main screen. 
         [0147]      FIGS. 15 and 16  illustrate how to control the mobile terminal  100  in a 3D camera shooting mode. Referring to  FIG. 15 , if the 3D camera shooting mode is selected when the mobile terminal  100  is held in its initial position, a preview image  510  of the front side of a subject  500  may be displayed on the display module  151  in a first display direction. If the mobile terminal  100  is rotated counterclockwise from its initial position by a predetermined amount, a preview image  520  of the right side of the subject  500  may be displayed on the display module  151  in a second display direction. If the mobile terminal  100  is rotated clockwise from its initial position by a predetermined amount, a preview image  530  of the left side of the subject  500  may be displayed on the display module  151  in a third display direction. 
         [0148]    Therefore, a viewer  400  may capture a preview image of the front side of the subject  500  when the mobile terminal  100  is held in its initial position, and may then capture a preview image of the left side or the right side of the subject  500  simply by rotating the mobile terminal  100  clockwise or counterclockwise. The captured preview images may be stored together in the memory  160 . 
         [0149]    Referring to  FIG. 16 , if a 3D viewer mode is selected, an image  540  of the front of the subject  500 , an image  550  of the right side of the subject  500  and an image  560  of the left side of the subject  500  may be displayed in the first, second and third display directions, respectively. Thus, the user can view each of the images  540 ,  550  and  560  simply by rotating the mobile terminal  100 . 
         [0150]      FIGS. 17 through 19  illustrate how to select and execute one of a plurality of objects displayed on the display module  151 . Referring to  FIG. 17 , first, second and third operation screens  570 ,  580  and  590  may be displayed at the same time in first, second and third display directions, respectively. Thereafter, if a touch input is received through the display module  151 , it may be determined which of the first, second and third operation screens  570 ,  580  and  590  is currently being viewed by the viewer  400  using a motion sensor (such as a gyro-sensor) or an optical sensor. Thereafter, an operation corresponding to the received touch input may be performed on whichever of the first, second and third operation screens  570 ,  580  and  590  is determined to be currently being viewed by a viewer  400 . It will hereinafter be described in further detail, with reference to  FIGS. 18 and 19 , how to determine which of the first, second and third operation screens  570 ,  580  and  590  is currently being viewed by the viewer  400 . 
         [0151]    Referring to  FIG. 18 , it may be determined which of the first, second and third operation screens  570 ,  580  and  590  is currently being viewed by the viewer  400  using a motion sensor such as a gyro-sensor. More specifically, if the mobile terminal  100  is rotated clockwise by a predetermined amount, as shown in  FIG. 18(   a ), it may be determined that the viewer  400  is on the right side of the mobile terminal  100 . Then, if the viewer touches the screen of the mobile terminal  100  or presses a key displayed on the display module  151 , one of a plurality of objects displayed on the third operation screen  620  may be selected, and an operation corresponding to the selected operation may be performed. 
         [0152]    Alternatively, referring to  FIG. 19 , it may be determined which of the first, second and third operation screens  570 ,  580  and  590  is currently being viewed by the viewer  400  using an optical sensor  700 . The optical sensor  700  may measure the slope of the mobile terminal  100  with respect to the viewer  400 , and may determine whether the user is in front of or on the left or right side of the mobile terminal  100  based on the result of the measurement. Thereafter, it may be determined which of the first, second and third operation screens  570 ,  580  and  590  is currently being viewed by the viewer  400  based on the results of the determination performed by the optical sensor  700 . In this manner, it is possible to perform an operation corresponding to each object displayed on whichever of the first, second and third operation screens  570 ,  580  and  590  is currently being viewed by the viewer  400 . 
         [0153]      FIGS. 20 through 23  illustrate how to control the mobile terminal in a 3D video call mode. Referring to  FIG. 20 , if the 3D video call mode is selected and a video call is connected, a screen  610  showing the image of a first participant in the video call, a screen  620  showing the image of a second participant in the video call, and a screen  630  showing the image of a third participant in the video call may be displayed at the same time in first, second and third display directions, respectively. Thus, a viewer  400  may engage in the video call while selectively viewing the images of the first, second and third participants in the video call simply by varying the viewing angle of the display module  151 . The screen  510  may be displayed at a normal frame rate, and the screens  520  and  530  may be displayed at a frame rate lower than the normal frame rate. In this manner, it is possible to reduce the processing load. 
         [0154]    Referring to  FIG. 21 , when the viewer  400  attempts to vary the viewing angle of the display module  151  and thus to view a screen  620  showing the image of the second participant, the screen  620  may be displayed at the normal frame rate, and a screen  610  showing the image of the first participant and a screen  630  showing the image of the third participant may be displayed at a frame rate lower than the normal frame rate. That is, whichever of the screens  610 ,  620  and  630  is currently being viewed by the viewer  400  may be displayed at the normal frame rate, and the other screens may be displayed at a frame rate lower than the normal frame rate. 
         [0155]    Referring to  FIG. 22 , if a touch input  635  is received through the display module  151 , it may be determined, based on the relative position of the viewer  400  to the mobile terminal  100 , which of the first through third participants has been selected by the viewer  400 . Thereafter, referring to  FIG. 23 , a screen showing the image of one of the first through third participants determined to have been selected by the viewer  400  may be displayed in the first display direction. 
         [0156]      FIG. 24  illustrates how to control the mobile terminal  100  in a 3D broadcast viewer mode. Referring to  FIG. 24 , first, second and third broadcast screens  670 ,  680  and  690  may be displayed at the same time in first, second and third display directions, respectively. Thus, the user can selectively view each of the first, second and third broadcast screens  670 ,  680  and  690  simply by varying the viewing angle of the display module  151 . 
         [0157]    If a user input such as a touch input is received through the display module  151 , it may be determined which of the first, second and third broadcast screens  670 ,  680  and  690  is currently being viewed by the user using a motion sensor (such s a gyro-sensor) or an optical sensor, and an operation corresponding to the received user input may be performed on whichever of the first, second and third broadcast screens  670 ,  680  and  690  is determined to be currently being viewed by the user. 
         [0158]      FIG. 25  illustrates how to control the mobile terminal  100  in a music play mode. Referring to  FIG. 25 , if the music play mode is selected, a screen  710  showing a playlist including a song currently being played, a screen  720  showing the lyrics of the song, and a screen  730  showing ID3 Tag information specifying the title and the singer(s) of the song and the title of the album including the song may be displayed at the same time in first, second and third display directions, respectively. 
         [0159]    In this manner, it is possible to improve the efficiency of use of the display region on the display module  151  by displaying a playlist, the lyrics of a song and ID3 Tag information regarding the song at the same time using a multi-view display. When the user places his or her finger near each music file in the playlist of the screen  710 , lyric information and ID3 Tag information regarding a corresponding music file may be displayed in the second or third display direction. Thus, the user can easily identify information regarding each music file in the playlist of the screen  710 . 
         [0160]      FIG. 26  illustrates how to control the mobile terminal  100  in a text-editing mode such as a mode for writing an email or text message. Referring to  FIG. 26 , in the text editing mode, a screen  740  showing a current page of an email or text message currently being written, a screen  750  a previous page of the email or text message, and a screen  760  showing a received email or text message may be displayed at the same time in first, second and third display directions, respectively. 
         [0161]    Thus, the user can instantly check an incoming email or text message from the screen  760  and can thus easily write a reply email or text message. In addition, the user can instantly check a previous page, if any, of an email or text message currently being written from the screen  750  and can thus effectively write long email or text messages. 
         [0162]    If an email or text message to be displayed on the display module  151  is two or more pages long, an icon representing each of the pages of the email or text message may be displayed on the display module  151 . Then, if one of the icons is selected, a page of the email or text message corresponding to the selected icon may be displayed in the second or third display direction. 
         [0163]      FIG. 27  illustrates how to control the mobile terminal  100  in a moving image file play mode. Referring to  FIG. 27 , if the moving image file play mode is selected, a screen  770  showing a moving image file currently being played, a screen  780  showing the subtitles of the moving image file, and a screen  790  showing a list of other moving image files may be displayed at the same time in first, second and third display directions, respectively. 
         [0164]    If the user chooses to watch the moving image file without the subtitles, the subtitles may be displayed in a different display direction from the moving image file. In this case, since the screen  780  is sometimes too large to simply display the subtitles, part of the screen  780  where the subtitles are not displayed may be used for language learning purposes. 
         [0165]    In this manner, the user can easily identify the moving image file currently being played and a list of other moving files stored in the mobile terminal  100 . Referring to  FIG. 27 , runtime information of the moving image file currently being played, instead of a progressive bar, may be displayed on the screen  780  along with the subtitles. 
         [0166]      FIGS. 28 through 30  illustrate how to control the mobile terminal  100  in a web-access mode. Referring to  FIG. 28 , if the web-access mode is selected, a screen  810  showing a current webpage, a screen  815  showing a previous webpage and a screen  817  showing a subsequent webpage may be displayed at the same time in first, second and third display directions, respectively. 
         [0167]    In this manner, the user can easily navigate from one webpage to another webpage simply by varying the viewing angle of the display module  151 . In addition, even if a cache is inactivated, it is possible to prevent unnecessarily frequent access to the web and thus to reduce the web-access charges. 
         [0168]    Alternatively, in the web-access mode, a screen  820  showing a current webpage may be displayed in the first display direction, and screens  825  and  827  each showing a webpage registered as a Favorite may be displayed in the second and third display directions, respectively, as shown in  FIG. 29 . That is, when one or more webpages worth revisiting are encountered while surfing on the internet with the mobile terminal  100 , the user may display the webpages on the screens  825  and  827 , and may continue to surf on the internet through the screen  820 . 
         [0169]    In this manner, the user can compare a plurality of webpages with one another while surfing on the web, and can easily navigate from one webpage to another webpage. Thus, it is possible to improve user convenience regarding web surfing. 
         [0170]      FIG. 30  illustrates how to provide a search function during web surfing. Referring to  FIG. 30 , a screen  830  showing a current webpage may be displayed in a first display direction. Then, when an interesting word or phrase is encountered from the screen  830 , the user may simply drag and drop the word or phrase on a screen  835  displayed in a second direction or a screen  837  displayed in a third direction and may thus be able to look up the word or phrase in a web-search engine or a dictionary set in the screen  835  or  837 . For this, a web-search page or a dictionary page may be displayed in an offline state in the second or third display direction. Then, when a word or phrase is dragged and dropped on the search page or the dictionary page, the web-search page or the dictionary page may be placed in an online state. 
         [0171]      FIG. 31  illustrates how to check an incoming text message or an incoming call in a predetermined operating mode using a multi-view display. Referring to  FIG. 31 , if an incoming text message or an incoming call is received while performing a predetermined operation (such as surfing on the web, watching a broadcast program or a moving image or viewing images) through a screen  840 , which corresponds to a current operating mode and is displayed in a first display direction, a screen  845  or  847  showing the incoming text message or the incoming call may be displayed in a second or third display direction, thereby allowing the user to continue to perform the predetermined operation through the screen  840 . 
         [0172]    Alternatively, if an incoming text message or an incoming call is received while performing the predetermined operation through the screen  840 , an icon indicating the existence of the incoming text message or the incoming call may be displayed on the screen  840 . Then, if the icon is dragged laterally by the user, the screen  845  or  847  may be displayed in the second or third display direction. 
         [0173]      FIG. 32  illustrates how to perform a privacy protection function using a multi-view display. Referring to  FIG. 32 , in order to protect privacy in public places or at public transportation, a screen  850  corresponding to a current operating mode may be displayed in a first display direction, and screens  855  and  857  each showing a dummy image or a default image selected by the user may be displayed in second and third display directions, respectively. 
         [0174]    In this manner, it is possible to effectively protect the privacy of the user. 
         [0175]    A multi-view display may be used to control various operations performed by the mobile terminal  100 . For example, for the purpose of learning English, the user may display English text in a first display direction, and may display a Korean translation of the English text and the definitions of keywords in the English text in a second or third display direction as reference materials for reading the English text. Alternatively, a screen showing a dictionary or automatic translation program may be displayed in the second or third display direction. Then, the user can be provided with the definition or a quick translation of the word or phrase simply by dragging and dropping the word or phrase onto the screen. 
         [0176]    In addition, a multi-view display may be used for two or more individuals to play a game such as a baseball game or a quiz game that requires the game players not to share some information with the mobile terminal  100 . For example, in the case of playing a baseball game with the mobile terminal  100 , a main game screen showing basic information (such as the runs scored) that needs to be shared between the game players may be displayed in a first display direction, and a pitcher screen for throwing a ball and a hitter screen for hitting a thrown ball may be displayed in second and third display directions, respectively. In the case of playing a quiz game with the mobile terminal  100 , a main screen showing basic information (such as the points made by each contestant) may be displayed in the first display direction, a screen showing quizzes and hints for the quizzes may be displayed in the second display direction, and a screen showing the correct answers to the quizzes may be displayed in the third display direction. 
         [0177]    Moreover, a multi-view display may be used in an image viewer mode. In the image viewer mode, a predetermined image may be displayed in a first display direction, and the thumbnail images or information of the predetermined image, an image previous to the predetermined image and an image subsequent to the predetermined image may be displayed in a second or third display direction. 
         [0178]      FIG. 33  illustrates how to display a previously-registered screen in a second or third display direction. Referring to  FIG. 33 , when there are one or more previously-registered screens that can be displayed in a second or third display direction in a predetermined operating mode, an icon group  910  may be displayed on a screen  900  displayed in a first display direction. The icon group  910  may include a plurality of icons  913  representing a plurality of previously-registered screens (such as screens  940  and  950 ) that can be displayed in the second display direction and a plurality of icons  915  representing a plurality of previously-registered screens (such as screens  920  and  930 ) that can be displayed in the third display direction. The arrangement of the previously-registered screens  920 ,  930 ,  940  and  950  may be changed by changing the arrangement of the icons in the icon group  910 . If one of the icons included in the icon group  910  is selected, a previously-registered screen corresponding to the selected icon may be displayed in the second or third display direction. More specifically, if the user places his or her finger near and thus selects one of the icons included in the icon group  910 , a previously-registered screen corresponding to the selected icon may be displayed in the second or third display direction. 
         [0179]    The mobile terminal according to the present invention and the method of controlling the mobile terminal according to the present invention are not restricted to the exemplary embodiments set forth herein. Therefore, variations and combinations of the exemplary embodiments set forth herein may fall within the scope of the present invention. 
         [0180]    The present invention can be realized as code that can be read by a processor (such as a mobile station modem (MSM)) included in a mobile terminal and that can be written on a computer-readable recording medium. The computer-readable recording medium may be any type of recording device in which data is stored in a computer-readable manner. Examples of the computer-readable recording medium include a ROM, a RAM, a CD-ROM, a magnetic tape, a floppy disc, an optical data storage, and a carrier wave (e.g., data transmission through the internet). The computer-readable recording medium can be distributed over a plurality of computer systems connected to a network so that computer-readable code is written thereto and executed therefrom in a decentralized manner. Functional programs, code, and code segments needed for realizing the present invention can be easily construed by one of ordinary skill in the art. 
         [0181]    As described above, according to the present invention, it is possible to provide a plurality of screens at the same time by displaying the screens on a multi-view display in different display directions. Thus, it is possible to view different screens from different viewing angles. 
         [0182]    In addition, according to the present invention, it is possible to display the images of multiple participants in a video call at the same time on a multi-view display in different display directions. Thus, it is possible to selectively view the images of the multiple participants simply by varying the viewing angle of the multi-view display. 
         [0183]    Moreover, according to the present invention, it is possible to display a plurality of broadcast screens at the same time on a multi-view display in different display directions. Thus, it is possible to quickly perform various operations on each of the broadcast screens simply by varying the viewing angle of the multi-view display without the need to switch between the broadcast screens. 
         [0184]    Furthermore, according to the present invention, it is possible to display various screens corresponding to a predetermined operating mode at the same time on a multi-view display in different display directions. Thus, it is possible to view the various screens and control various operations corresponding to the predetermined operating mode simply by varying the viewing angle of the multi-view display. 
         [0185]    According to still further embodiments, consider the scenario in which a user views a center screen while the device displays second and third screens viewable on either side of the center screen. An example of this is shown in  FIG. 22 . In the present embodiment, a user may be permitted to select a displayed object (e.g., image) that is beyond the viewing boundary of the center screen, such as the right-most screen, and then drag the object to the center and/or left most-most screen. As such, the device may therefore function as an extended desktop or operating platform, viewable in discrete screens but permitting object manipulation among and between the screens. 
         [0186]    One alternative to the just-described extended desktop example is to permit context switching between and among the screens. In this embodiment, a user may drag the screen, and any related content, icons, etc., from a first screen to a second screen. As a result, the content from the first screen is switched to being displayed on the second screen, and the content from the second screen is switched to so that it displayed on the first screen. 
         [0187]    While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the following claims.