Digitizing tablet system
US4644102A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 29, 1985 |
| Grant date | Feb 17, 1987 |
| Priority date | — |
| Expiry date | Mar 29, 2005 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F2203/04107
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A digitizing tablet is disclosed in which two multiplexors are connected to alternate conductive loop elements in each plane of elements. The two multiplexors are connected to a differential amplifier. The signals from the differential amplifier are demodulated. The demodulated signal is provided to an integrator. A microprocessor controlled reset switch is connected across the integrator to reset the integrator after the completion of each measurement. Grounded copper strips are used in the space formed within and between the conductive loop elements of the digitizing tablet to shield the loop elements from capacitive interference.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.