Patent · US Expired

Method and system for optical measurement via a resonator having a non-uniform phase profile

US7193725B2 · kind B2 · utility

9Cited by
4References
19Claims
0Family size

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Key dates

Filing dateFeb 2, 2004
Grant dateMar 20, 2007
Priority date
Expiry dateAug 12, 2025

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B26/001
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A method and system for optical measurement via a resonator having a non-uniform phase profile provides a mechanism for measuring and/or detecting sub-micron surface features with increased resolution. A second surface forming part of a resonator is illuminated through a first partially reflective surface that has a non-uniform phase profile that transitions from negative to positive phase with respect to a resonance phase value of the resonator. As a result, a reduced spot size is produced at the second surface, which enhances the resolution of a measurement and/or detection of surface features on the second surface. Additionally, if a discontinuity is provided in the non-uniform phase profile, interaction of the discontinuity with surface features of the second surface will provide enhanced resolution of the surface features. The resolution of the system is improved over the resolution that can be attained using a Fabry-Perot resonator.

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