Open AccessDesign of phase shifting algorithms: fringe contrast maximum
Author(s) -
Yangjin Kim,
Kenichi Hibino,
Naohiko Sugita,
Mamoru Mitsuishi
Publication year - 2014
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.22.018203
Subject(s) - optics , contrast (vision) , amplitude , phase (matter) , interferometry , sample (material) , observational error , signal (programming language) , algorithm , harmonic , computer science , physics , mathematics , acoustics , statistics , quantum mechanics , thermodynamics , programming language
In phase shifting interferometry, the fringe contrast is preferred to be at a maximum when there is no phase shift error. In the measurement of highly-reflective surfaces, the signal contrast is relatively low and the measurement would be aborted when the contrast falls below a threshold value. The fringe contrast depends on the design of the phase shifting algorithm. The condition for achieving the fringe contrast maximum is derived as a set of linear equations of the sampling amplitudes. The minimum number of samples necessary for constructing an error-compensating algorithm that is insensitive to the jth harmonic component and to the phase shift error is discussed. As examples, two new algorithms (15-sample and (3N - 2)-sample) were derived that are useful for the measurement for highly-reflective surfaces.