Digitizing tablet system having stylus tilt correction
US4577057A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 2, 1984 |
| Grant date | Mar 18, 1986 |
| Priority date | — |
| Expiry date | Mar 2, 2004 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F3/03545
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A digitizing tablet system of the type including a tablet, a stylus and associated electronics which is constructed to correct for tilt errors when the stylus axis is tilted relative to the tablet is disclosed. The tablet includes a housing having a rectangular coordinate grid of electrical conductors. The stylus includes an elongated tubular member having a tip at one end, a first coil which is located at a first axial distance from the tip and a second coil which is located at a second axial distance from the tip, the second distance being different from the first distance. A voltage signal is applied to each coil sequentially. The signal applied to each coil induces a voltage in each conductor in the grid. The induced voltages are processed to produce a first and a second data signal, the first data signal corresponding to the position of the first coil relative to the grid and the second data signal corresponding to the position of the second coil relative to the grid, with the difference in the two data signals, if any, being caused by tilt of the stylus. The two data signals are then processed to produce a third data signal corresponding to the position of the tip of the styl…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.