Coordinate input device with display

摘要

A coordinate input device with a display includes a tablet composed of two position detecting units each formed by alternately arranged exciting and detecting lines parallel to each other on a magnetic member in the form of a sheet. These units are overlaid one upon the other so that exciting and detecting lines of one unit extend orthogonally with respect to those of the other. A planar display is overlaid on the tablet. The device further includes a position designating magnetic generator which locally applies a magnetic bias to the magnetic members of the tablet. The exciting lines of the tablet are supplied with an alternating current of a predetermined cycle by a driving current source. A position detecting circuit detects the coordinate values of a position designated by the position designating magnetic generator from the induced voltages respectively generated from the detecting lines of the tablet. The display is driven by a display control circuit. A modulating and demodulating circuit converts data represented by the coordinate values into a signal suitable for a transmission line and vice versa. The device further includes a processor which controls the above-described members and circuits. Position designation with respect to the tablet is effected by the position designating magnetic generator from the upper side of the display, whereby it is possible to input a position signal to the tablet under the display with high accuracy.