Defocus measurement using speckle correlation

Authors
Krishnakumar, V Asundi, AK
Citation
V. Krishnakumar et Ak. Asundi, Defocus measurement using speckle correlation, J MOD OPT, 48(5), 2001, pp. 935-940
Citations number
4
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science","Optics & Acoustics
Journal title
JOURNAL OF MODERN OPTICS
ISSN journal
09500340 → ACNP
Volume
48
Issue
5
Year of publication
2001
Pages
935 - 940
Database
ISI
SICI code
0950-0340(200104)48:5<935:DMUSC>2.0.ZU;2-6
Abstract
A technique using correlation fringes is presented to estimate the out-of-p lane displacement of the image plane. The width of the fringe is estimated using autocorrelation of the Young's fringes and the visibility of the auto correlation of these fringes are used as an estimator of the focusing error . This technique allows us to estimate focusing errors of the order of few tens of microns.