Calibration for cylindrical specimens in grazing-incidence interferometry via integration of difference measurements.
Cylindrical specimens may be tested advantageously by using grazing-incidence interferometry. A multiple positions test in combination with rotational averaging has recently been used to separate the surface deviations of the specimen from the interferometric aberrations. To reduce the measuring time and to check whether the results are reliable, a second procedure is now investigated, which uses the principle of the multiple positions test to determine quantities proportional to the difference quotients of the surface deviations. After numerical integration, the results can be compared with those obtained previously by rotational averaging. The measurement principle is described, and calibration results are presented.
Mantel
Klaus
K
Institute of Optics, Information and Photonics (Max-Planck Research Group), Friedich-Alexander-Universität Erlangen-Nürnberg, Germany. Klaus.Mantel@optik.physik.uni-erlangen.de
Lamprecht
Jürgen
J
Lindlein
Norbert
N
Schwider
Johannes
J