Open AccessMultiple intensity reference interferometry for the correction of sub-fringe displacement non-linearities
Author(s) -
Angus Bridges,
Andrew Yacoot,
Thomas Kissinger,
Ralph P. Tatam
Publication year - 2021
Publication title -
measurement science and technology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.48
H-Index - 136
eISSN - 1361-6501
pISSN - 0957-0233
DOI - 10.1088/1361-6501/ac3aad
Subject(s) - linearity , displacement (psychology) , optics , interferometry , harmonics , astronomical interferometer , residual , limit (mathematics) , physics , intensity (physics) , nanometrology , metrology , computer science , mathematics , algorithm , mathematical analysis , psychology , quantum mechanics , voltage , psychotherapist
Displacement measuring interferometers, commonly employed for traceable measurements at the nanoscale, suffer from non-linearities in the measured displacement that limit the achievable measurement uncertainty for microscopic displacements. Two closely related novel non-linearity correction methodologies are presented here that allow for the correction of non-linearities in cases where the displacement covers much less than a full optical fringe. Both corrections have been shown, under ideal conditions, to be capable of reducing all residual non-linearity harmonics to below the 10 pm level.