Apparatus and method for obtaining phase corresponding to object position
US8457914B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Dec 2, 2010 |
| Grant date | Jun 4, 2013 |
| Priority date | — |
| Expiry date | May 22, 2031 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01D5/24476
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The apparatus corrects multi-phase signals for detecting a position of an object and obtains a phase corresponding to the position of the object. The apparatus includes a correcting unit correcting the multi-phase signals with error coefficients, respectively, a phase calculating unit performing calculation for the corrected multi-phase signals to obtain the phase, a regression unit performing regression for the calculated phases to obtain reference phases, a Fourier transform unit respectively performing Fourier transform for the corrected multi-phase signals whose phases having been respectively changed into the reference phases, and an updating unit updating, using Fourier coefficients obtained by the Fourier transform unit, the error coefficients respectively corresponding to the Fourier coefficients. The updating unit updates the error coefficients if a regression error in the regression performed by the regression unit satisfies a predetermined condition.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.