Acoustic writing combination, comprising a stylus with an associated writing tablet

摘要

An acoustic writing combination, includes a stylus with an associated writing tablet. The stylus is provided with two ultrasonic sound sources which upon contact of the stylus with the writing tablet emit pulse- shaped sound signals which are picked up by at least two microphones which are located at the edge of the writing tablet. The two sound sources are situated at different distances from the stylus tip and are operated to alternately produce ultrasonic signals. Point-shaped or circular sound sources may be employed. The circular sound sources may then comprise piezo-electric ceramic rings.