Patent ID: 8665211

Claim:
A position detecting device comprising: a sensor unit including a plurality of first loop coils that are arranged relative to each other along a first direction and a plurality of second loop coils that are arranged relative to each other along a second direction intersecting with the first direction, the first and second loop coils being configured to both generate a magnetic field to induce an induced current in a coil of a position indicator placed near the first and second loop coils and to receive a signal from the position indicator; a yoke sheet provided on a side of the sensor unit that is opposite to a side of the sensor unit that faces a position indicator; an auxiliary loop coil provided at a corner part of the sensor unit and configured to only generate a magnetic field to induce an induced current in the coil of the position indicator placed near the auxiliary loop coil; a signal transmitter configured to transmit a signal to one or more of the first loop coil, the second loop coil, and the auxiliary loop coil in order to generate a magnetic field therefrom; and a controller configured to selectively supply the signal from the signal transmitter to one or more of the first loop coil, the second loop coil, and the auxiliary loop coil to generate a magnetic field therefrom, and to selectively receive the signal from the position indicator via one or more of the first loop coil and the second loop coil.