Trackball Input Device with Cursor Positioning Control and 360-Degree Window Scrolling Modes
Original Publication Date: 2002-Jan-02
Included in the Prior Art Database: 2003-Jun-20
Disclosed is a single-trackball input device which supports the control of cursor positioning and the 360-degree scrolling of window contents through the same trackball mechanism. The device is intended for use with any computer system running a graphical windowing operating system. The novel and unique characteristics of this device are: 1) the use of a single trackball as opposed to a trackball with an additional scrolling wheel control to either position the cursor or scroll the contents of a window, thereby eliminating the need to reposition the hand from trackball to wheel when switching between control modes; 2) support for scrolling in any direction (360 degrees) through use of the trackball as opposed to constraining the scrolling movement to either a vertical or horizontal axis relative to the window as is true with a scrolling wheel. A typical embodiment for this device appears as shown in Figure 1. The trackball input device (1) is connected to a typical computer system (2). The computer system is running an operating system that supports the display of graphical windows. One example of this type of operating system is Windows 2000 Professional (TM of Microsoft Corporation). A common trackball device driver modified to include support for mode switching and 360-degree scrolling is also present. Note, however, that the functions provided by this device driver could also be incorporated directly into the firmware of the trackball. Movement of the trackball control (4) is translated through well-known and commonly used algorithms into either movement of the on-screen cursor or scrolling of the contents of the active window. The user selects which mode is active by clicking a dedicated mode toggle button (3) which is provided in addition to the "left"- and "right"-click buttons (5 and 6) that typically are found on trackball devices. 1 In cursor control mode, movement of the trackball in any direction results in a corresponding movement of the cursor position (8) shown on the display (7). An illustration of one such movement is shown in Figure 2.