Koordinateneingabevorrichtung und zugehöriges Singalübertragungssystem

摘要

A coordinate inputting apparatus has a separating circuit (1), a cable (2) and a position indicating pen (3). The separating circuit (1) has a low pass filter (4) for removing an alternating current component from a signal transmitted to a signal line (2a) and a band pass filter (5) for passing only a position information signal in a predetermined frequency band with respect to the signal transmitted to the signal line (2a). The cable (2) is constructed by the signal line (2a), a switching signal line (SW) and a ground line (GND). The signal line (2a) is used to supply power to the position indicating pen (3) and transmit a detecting signal from the position indicating pen (3) to each of an X-coordinate detecting circuit (30) and a Y-coordinate detecting circuit (31). The position indicating pen (3) has a low pass filter (7) and a band pass filter (8). A signal transmitting system of this coordinate inputting apparatus and other coordinate inputting apparatuses are also shown.