Pointer detection apparatus and pointer detection method
US8587535B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 25, 2010 |
| Grant date | Nov 19, 2013 |
| Priority date | — |
| Expiry date | Dec 18, 2030 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F3/0446
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A pointer detection apparatus includes a conductor pattern with first conductors disposed in a first direction and second conductors disposed in a second direction that crosses the first direction, and a code string signal production circuit for producing signals based on orthogonal code strings with phases different from each other and supplying the produced signals to the first conductors. The apparatus also includes a signal detection circuit connected to the second conductors for detecting a signal corresponding to a variation of electrostatic capacitance between the conductor pattern and a pointer, an analog to digital conversion (ADC) circuit for converting the signal output from the signal detection circuit into a digital signal comprising a word string of multiple bits, and a correlation detection circuit for determining correlation values between the code strings and the word string. The apparatus also includes a memory for storing correlation values successively output from the correlation detection circuit, wherein the pointer is detected based on the correlation values.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.