Patent · US Expired

Phase measuring method and apparatus for multi-frequency interferometry

US7304745B2 · kind B2 · utility

1Cited by
1References
30Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 29, 2003
Grant dateDec 4, 2007
Priority date
Expiry dateApr 18, 2024

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01B11/25
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

The invention provides a novel method for absolute fringe order identification in multi-wavelength interferometry based on optimum selection of the wavelengths to be used. A theoretical model of the process is described which allows the process reliability to be quantified. The methodology produces a wavelength selection which is optimum with respect to the minimum number of wavelengths required to achieve a target dynamic measurement range. Conversely, the maximum dynamic range is produced from a given number of optimally selected wavelengths utilized in a sensor. The new concept introduced for optimum wavelength selection is scalable, i.e. from a three wavelength system to a four wavelength system, from four wavelengths to five, etc.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.