Method for measuring distance between coordinate indicator and coordinate input device
US8797300B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 16, 2009 |
| Grant date | Aug 5, 2014 |
| Priority date | — |
| Expiry date | Oct 2, 2030 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F2203/04101
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method for measuring a distance between a coordinate indicator and a coordinate input device, which belongs to the technical field of computer peripheral equipments. The method comprises the steps of measuring an actual amplitude of an output signal of a receiving coil in the electromagnetic induction plate by a measurement circuit in the electromagnetic induction plate; determining a distance between the coordinate indicator and the coordinate input device in accordance with the actual amplitude of the output signal, a nominal amplitude of the output signal, and a preset reference amplitude of signal. In the present invention, the distance between the coordinate indicator and the coordinate input device is determined by converting an actual amplitude of the output signal of the receiving coil at one time to a nominal amplitude of the output signal normalized by a reference amplitude of signal, which overcomes the defect of the prior art which can not indicate a distance between the coordinate indicator and the coordinate input device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.