Abstract: In an optical digitizer, a cursor is movable on a plane surface having coordinate axis. The cursor includes a source of light that is scanned across the coordinate system, and a detector receiving light from the angle to which the beam is instantaneously directed. The coordinate system has curved mirrors at the origin and point spaced from the origin along the axis thereof, and plane mirrors extending along the axis. A calculator determines the position of the cursor in the coordinate system by triangulation. Alternatively, the cursor may be a curved mirror, with rotating light sources and detectors positioned at determined points in the coordinate system.

Abstract: A mouse comprises a cover and a displacement pad which is displaced upon movement of the mouse over a surface. Displacement transducer means, e.g., strain gauges mounted in a parallel arm linkage, are used to ascertain direction of motion. Noise created by sliding motion is monitored by a microphone, the output of which is a function of velocity and therefore distance. The microphone may be mounted to the displacement pad, and the pad and microphone covered with a friction and vibration enhancing medium, such as felt. The displacement pad may also be suspending in a computer terminal and be "stroked" to achieve displacement and noise. Calculating means produce cursor dot control signals based on displacement and noise.