Digitizer and position determination method therefor
US5670754A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 27, 1995 |
| Grant date | Sep 23, 1997 |
| Priority date | — |
| Expiry date | Mar 27, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F3/046
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A digitizer and a method for calculating the position coordinates indicated by a position indicator on a tablet. The position indicator has a coil that electromagnetically interacts with the loop coil group of the tablet. A signal detection unit, a "sum" signal specifying unit, and a coordinate determination unit are utilized. The signal detection unit sequentially selects two loop coils as a loop coil pair from the loop coil group of the tablet and acquires a "sum" of and a "difference" between signals generated in respective coils of each loop coil pair. The "sum" signal specifying unit specifies one of the loop coil pairs of the loop coil group which generates a "sum" signal of a maximum absolute value when the coil of the position indicator and the loop coil group of the tablet are brought into an interaction state. The coordinate determination unit determines position coordinates on the tablet designated by the position indicator, on the basis of a "difference" signal of the specified loop coil pair.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.