Noise cancellation in digitizing system and method
US4859814A · kind A · utility
21Cited by
2References
14Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 29, 1988 |
| Grant date | Aug 22, 1989 |
| Priority date | — |
| Expiry date | Aug 29, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F3/046
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A digitizing system includes a differential noise reduction technique wherein spaced parallel grid conductors in a tablet are differentially sensed in order to cancel out locally induced noise signals. Grid conductors also are sensed in a single ended fashion to initially locate a grid conductor conducting a larger induced carrier signal amplitude than any other grid conductor and produce amplitude data that is used to eliminate ambiguities arising from differential sensing of pairs of spaced grid conductors.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.