| 摘要 |
A two-dimensional coordinate measuring pad for use, for example, to recognize handwriting. A high resistivity sheet is bounded by a lower resistivity border connected to a switched voltage source to cause a current to flow first in one direction and then in a perpendicular direction through the resistive sheet. Potential measurements at an array of precisely predetermined points are employed to generate a set of correction values which are stored in a programmable read-only memory. Thereafter, to indicate the position of an arbitrarily selected contact point on the sheet, the stored correction values for the nearest points are fetched form the memory and combined with the measured values to produce adjusted output values which more accurately indicate the positional coordinates of the contact point. |
