PURPOSE: To more accurately specify a detection position by processing a reception signal from the electrode lines of a tablet with a signal reception means having amplifiers and signal-noise discriminators.

CONSTITUTION: When a pen 2 irradiating a pulse signal is abutted on the desired position of the tablet 3, a waveform by a static capacitance is induced to the electrode lines 4 and 5. The waveform is divided into an X-coordinate position signal and a Y-coordinate position signal by an X-switching circuit 11 and a Y-switching circuit 12 in the reception means 10 and they are processed by respective amplifiers 13 and 14 and the signal-noise discriminators 15 and 16. Then, they go to signals corresponding to position information. Thus, the pen becomes light in weight and an operation is facilitated with such constitution. Noise is removed and the detection position can more accurately be specified.