Abstract: The present invention provides a computer joystick which will convert movements of its control stick into digital signals. The computer joystick comprises a housing with an opening on its top, a control stick, and two optical sensing devices for detecting movements of the control stick in two perpendicular directions and generating corresponding displacement signals. The control stick comprises a handle installed at its top section, a ball-shaped portion installed at its middle section, and a driving mechanism installed at its bottom section. Each of the optical sensing devices comprises an optical panel comprising a plurality of light transmitting holes installed on it, a light source and a plurality of optic sensors installed at opposite sides of the optical panel, and a plurality of comparators for comparing detecting signals generated by the optic sensors so as to generate the displacement signals.

Abstract: This invention provides an optical sensing system for detecting displacements of a slidable frame along an elongated plate of the system and generating corresponding position or displacement signals. The optical sensing system comprises a housing, an elongated plate horizontally installed in the housing having a plurality of positioning holes and a plurality of parallel conductors installed in it, a slidable frame having a sliding hole in its middle for slidably engaging the elongated plate, an optical sensor installed in the frame and slidably wired to the parallel conductors of the elongated plate for detecting the positioning holes of the elongated plate and generating corresponding sensing signals, and a control circuit wired to the parallel conductors of the elongated plate for converting the sensing signals into corresponding position signals or displacement signals.