[0005]Tablet computers have been developed on the basis of advantageous effects of desktop, notebook and handheld computers. A notebook computer is referred to as a mobile computer. But, when the notebook computer is used, its main body must be positioned on a fixed base surface. Meanwhile, a tablet computer can be easily used on a user's hand like a personal digital assistant (PDA). The tablet computer enables the user to directly take notes on a monitor using an electronic pen in place of a keyboard. Since an input unit in the tablet computer is based upon a touch screen, a special input unit such as a mouse is not necessary, and hence, the tablet computer can be conveniently used. Thus, the tablet computer has excellent mobility and convenience. Furthermore, since the tablet computer includes the computer's basic components inside the monitor, its exterior is simple. A portable computer can implement the notebook computer function and the tablet computer function in a single system in order for the user to conveniently and selectively use a notebook computer function and a tablet computer function.
[0006]A prior art portable computer automatically converts a display mode of its display to a landscape or portrait mode, which is a corresponding default display mode for a converted system mode when the system mode is converted from a notebook mode into a tablet mode or vice versa, or when a docking device is connected. For example, a display operation of the display is carried out in the landscape mode when the system mode is converted into the notebook mode as shown in FIG. 2, and the display operation of the display is carried out in the portrait mode when the system mode is converted into the tablet mode as shown in FIG. 3. When the docking device is connected to the prior art portable computer, the display operation of the display is carried out in the landscape or portrait mode set appropriately to an application program of the connected docking device. Thus, the default display mode predetermined to be the most appropriate for the system mode is automatically set.
[0007]Since the prior art portable computer automatically forces the display to carry out the display operation in only one display mode previously determined for a system mode or a docking device when the system mode is converted or the docking device is connected, the display mode of the display cannot be arbitrarily changed to the user-desired display mode. For example, the display operation of the display cannot be automatically carried out in the portrait mode when the system mode is converted into the notebook mode. Further, the display operation of the display cannot be automatically carried out in the landscape mode when the system mode is converted into the tablet mode. Consequently, the user cannot change the LCD display mode automatically to various display modes other than the previously determined display mode.
[0008]In addition, the prior art portable computer outputs a wallpaper image of a predetermined aspect ratio such as a landscape mode having an aspect ratio of ‘1024×768’ to the display as shown in FIG. 4. The wallpaper image may consist of a logo of a portable computer manufacturer, a particular background picture, etc.
[0009]When a user requests, for example using a touch screen digitizer or a keyboard (not shown), a display mode of the display to be converted from the landscape mode into the portrait mode or a 90 degree rotational mode in which the display operation of the display is carried out in a direction rotated by 90 degrees, the display mode of the display is changed to the requested portrait mode or 90 degree rotational mode. However, the landscape wallpaper image having the aspect ratio of ‘1024×768’ is converted into a resized portrait wallpaper image having an aspect ratio of ‘768×1024’ or ‘600×800’ or a wallpaper image that is rotated by 90 degrees and resized to have an aspect ratio of ‘1024×768’ by a video controller, and then, the converted wallpaper image is outputted to the display. Accordingly, there is a problem in that a logo, a background pattern, or / and a background picture included in the wallpaper image are all displayed in a distorted state as shown in FIG. 4.
[0010]The above references are incorporated by reference herein where appropriate for appropriate teachings of additional or alternative details, features and / or technical background.SUMMARY OF THE INVENTION