Device and system for locating the position of the tip of a pen on a digitising board

Abstract

The present invention relates to a device intended for locating the tip of a pen on a writing board, the pen and the board being part of a writing digitizing system further comprising at least two magnetic dipoles, each being coupled with a current source so as to create distinct magnetic fields which are perpendicular to the writing board. According to the invention, the pen comprises a first sensor intended for measuring the magnetic fields produced by each magnetic dipole, and a second sensor intended for measuring the inclination angle θ of the pen with respect to the vertical, and transmission means for delivering data supplied by the first and second sensors to a processing unit to compute the position of the pen tip onto the writing surface in terms of the measured magnetic fields and angle θ values.

Dependencies are inferred from the claim text.