Charge Flow Cursor or stylus plate fe Charge AMPR $V Voltage V Time for which switch is close FIGURE 89.5(a)Digitizer tablet.( Courtesy of Numonics )(b) Capacitive technology. Source: After T. E. Davies et al Digitizers and input tablets, in Input Devices, S Sherr, Ed, New York: Academic Press, 1988, P. 186. With permission. Mouse The mouse has gone a long way from its original invention by Engelbart in 1965, through its redesign and introduction by Apple as a main input device, and its general acceptance by computer users as an important addition to the group of input devices. It should be noted, in passing, that the mouse is essentially an upside down trackball, although the latter is now being referred to as an upside-down mouse. However, the trackball came first and is described further in the next se e 2000 by CRC Press LLC© 2000 by CRC Press LLC Mouse The mouse has gone a long way from its original invention by Engelbart in 1965, through its redesign at Xerox and introduction by Apple as a main input device, and its general acceptance by computer users as an important addition to the group of input devices. It should be noted, in passing, that the mouse is essentially an upside￾down trackball, although the latter is now being referred to as an upside-down mouse. However, the trackball came first and is described further in the next section. FIGURE 89.5 (a) Digitizer tablet. (Courtesy of Numonics.) (b) Capacitive technology. (Source: After T. E. Davies et al., “Digitizers and input tablets,” in Input Devices, S. Sherr, Ed., New York: Academic Press, 1988, p. 186. With permission.)