Open AccessEvaluation of absolute form measurements using a tilted-wave interferometer
Author(s) -
Ines Fortmeier,
Manuel Stavridis,
Axel Wiegmann,
Michael Schulz,
Wolfgang Osten,
Clemens Elster
Publication year - 2016
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.24.003393
Subject(s) - optics , interferometry , piston (optics) , optical path length , accuracy and precision , range (aeronautics) , physics , measurement uncertainty , wavefront , materials science , quantum mechanics , composite material
Tilted-wave interferometry is a promising measurement technique for the highly accurate measurement of aspheres and freeform surfaces. However, the interferometric fringe evaluation of the sub-apertures causes unknown patch offsets, which currently prevent this measurement technique from providing absolute measurements. Simple strategies, such as constructing differences of optical path length differences (OPDs) or ignoring the piston parameter, can diminish the accuracy resulting from the absolute form measurement. Additional information is needed instead; in this paper, the required accuracy of such information is explored in virtual experiments. Our simulation study reveals that, when one absolute OPD is known within a range of 500 nm, the accuracy of the final measurement result is significantly enhanced.