摘要 |
<p>A device for determining position coordinates of points on a surface, have a cursor structure, a grid structure, and a signal processor. The cursor structure has a cursor coil and a signal generator to impress a reference phase voltage to the coil. Voltages induced from the cursor coil in conductors of the grid structure are processed in the signal processor to produce a position dependent phase voltage. For the signal processor, reference phase pulses are obtained from a voltage induced in an auxiliary grid conductor provided in the grid structure.</p> |