Point detecting device and method of same.

摘要

The invention relates to a point detecting device and a method for providing coordinate information which is indicated by a pointing device. This point detecting device is adapted for a large scaled system which is required to be operated at a low cost and at high accuracy. The point detecting device transmits signals from both ends of the loop coil arrangement towards the pointing device, and/or receives at both ends the signals generated by the electromagnetic function between the loop coil arrangement and the pointing device. The errors owing to the variations caused in the signal level and phase in response to the propagation constant of the loop coil arrangement can be reduced by adding the received signal pair. <IMAGE>