OPTICAL COORDINATING INPUT APPARATUS

摘要

The optical coordinate input unit includes light-emitting elements arranged so that their optical axes cross one another. Light- receiving elements are arranged opposite the lihgt-emitting elements. A driving circuit (1) switches the emitting elements on and off to give the appropriate light signals. The first switching arrangement (6) passes the signals from the driving circuit to the light-emitting units. A second switching arrangement (7) deals with the sensor signals and selects the light-receiving elements according to the signals arriving from the light-emitting emements.