Accurate phase extraction algorithm based on Gram–Schmidt orthonormalization and least square ellipse fitting method. Issue 10 (7th June 2018)

• Record Type: Journal Article
• Authors: Lei, Hebing; Yao, Yong; Liu, Haopeng; Tian, Yiting; Yang, Yanfu; Gu, Yinglong
• Is Part Of: Journal of modern optics. Volume 65:Issue 10(2018)
• Page Start: 1199
• Page End: 1209
• Publication Date: 2018-06-07
• Subjects: Phase extraction -- Gram–Schmidt orthonormalization -- ellipse fitting -- interferometry; Optics -- Periodicals; 535
• DOI: 10.1080/09500340.2018.1429681
• Languages: English
• ISSNs: 0950-0340

Abstract

Abstract: An accurate algorithm by combing Gram–Schmidt orthonormalization and least square ellipse fitting technology is proposed, which could be used for phase extraction from two or three interferograms. The DC term of background intensity is suppressed by subtraction operation on three interferograms or by high-pass filter on two interferograms. Performing Gram–Schmidt orthonormalization on pre-processing interferograms, the phase shift error is corrected and a general ellipse form is derived. Then the background intensity error and the corrected error could be compensated by least square ellipse fitting method. Finally, the phase could be extracted rapidly. The algorithm could cope with the two or three interferograms with environmental disturbance, low fringe number or small phase shifts. The accuracy and effectiveness of the proposed algorithm are verified by both of the numerical simulations and experiments.