Position pointing device having resonant circuit with sequentially changed characteristics and combination thereof with position detecting device

摘要

A position pointing device for use with a digitizing tablet sequentially transmits plural different kinds of non-positional information to the tablet. The position pointing device varies a resonance characteristic of a resonance circuit in accordance with plural kinds of amount information, during each of plural sequential time slots. A tablet detects a resonance characteristic of the resonance circuit. The frequency and/or amplitude of the AC field coupled from the resonance circuit to the tablet are varied. The frequency variation is sufficiently small that it can be detected with a synchronous detector driven by a single frequency.