1. Field of the Invention
The present invention relates to an apparatus for manipulating an object displayed on a display device by using a touch screen.
As use of computer systems for data processing has become widespread in recent years, more and more users are being required to handle same, i.e., to input data and converse with data processors such as work stations and personal computers. A vast variety of application programs are available for recent data processors and even a complicated application can be processed by using such application programs in combination. However, it is a great problem that such data processors are very difficult to handle, especially to manipulate an object displayed on a display device, for those who have less than a substantial knowledge of computers.
Therefore, an apparatus for manipulating an object displayed on a display device, which is easily handled even for a person who has no special knowledge of computers, is in great demand.
2. Description of the Related Art
FIG. 1 illustrates a computer system with a conventional user interface.
A computer system with a conventional user interface consists mainly of a central processing unit (CPU) 4, a main memory 5, a keyboard/mouse 2, a frame memory 6 and a hard disk interface 71, which are interconnected via a system bus, and also a hard disk 7 and a display unit 3, which are connected to system bus via the hard disk interface and the frame memory 6, respectively. The main memory 5 stores a system control program and application programs which handle graphics processing, and provides a work area for use by the programs. The CPU 4 performs display operations under control of the programs. The hard disk 7 stores a data file for graphics to be displayed on the display unit 3. The frame memory 6 stores a frame of picture (or object) data to be displayed on the display unit 3.
To manipulate an object displayed on a display unit 3 in the above system, an operator is required to input a command, for manipulating the object by using a keyboard/mouse 2, or to select an icon (a symbolic representation of a computer function), displayed on a display unit 3 by using the keyboard/mouse 2, in order to command a desired function. However, it is troublesome and annoying to use a keyboard/mouse and icons and a person with less than a substantial knowledge of computers tends to be reluctant even to touch a keyboard/mouse.
Therefore, it is a great problem that such data processors are very difficult to handle for those who have less than a substantial knowledge of computers.