Position determining apparatus for pointer on presentation screen, splits laser beam using semitransparent mirror, which allows reflected beam to be detected

摘要

The position determination involves using a laser beam (l) that is deflected by a rotary mirror. The beam is split by a semitransparent mirror which allows part (e) of the beam reflected by conformal reflectors (A,B,C) to be detected, and thus an angle (w) to be determined.