## Efficient nonlinear algorithm for envelope detection in white light interferometry

JOSA A, Vol. 13, Issue 4, pp. 832-843 (1996)

http://dx.doi.org/10.1364/JOSAA.13.000832

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### Abstract

A compact and efficient algorithm for digital envelope detection in white light interferograms is derived from a well-known phase-shifting algorithm. The performance of the new algorithm is compared with that of other schemes currently used. Principal criteria considered are computational efficiency and accuracy in the presence of miscalibration. The new algorithm is shown to be near optimal in terms of computational efficiency and can be represented as a second-order nonlinear filter. In combination with a carefully designed peak detection method the algorithm exhibits exceptionally good performance on simulated interferograms.

© 1996 Optical Society of America

**History**

Original Manuscript: October 11, 1994

Revised Manuscript: October 25, 1995

Manuscript Accepted: September 19, 1995

Published: April 1, 1996

**Citation**

Kieran G. Larkin, "Efficient nonlinear algorithm for envelope detection in white light interferometry," J. Opt. Soc. Am. A **13**, 832-843 (1996)

http://www.opticsinfobase.org/josaa/abstract.cfm?URI=josaa-13-4-832

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