Study onanautomaticprocessingtechniqueofthecircleinterference fringe forfineinterferometry

摘要

The fringecentermethod(FCM)isanimportantdigitalprocessingtechniqueoffringepatternsanalysisfor interferometry.Inthispaper,animprovedautomaticprocessingtechniquebasedonFCMwaspresented,which correlatedtheprocessinglinkandtheloopedfeatureofthecirclefringepattern.Italsointegratedseveraltechniques includingnoiseremoval,thefringethinning,thefringepatching,assignmentofthefringeordersandwavefront reconstructionandcanbeexecutedorderlyandautomatically.Basedonthenewthealgorithmsofthefringepatching and assignmentofthefringeorders,thefringefeatureinformationwasextractedautomaticallyandtheinterference wavefrontwasreconstructedbyZernikepolynomialfittingmethod.Withtheautomaticprocessingtechnique,the circleinterferencefringeofthefinepolishedaluminumdiskssurfacecapturedbytheTwyman–Greeninterferometer was processed,andthesurfaceprofileandtheparametersofthediskwereobtainedautomatically.Theexperiments show thattheimprovedautomaticprocessingtechniquewasmoreaccurateandfastinmeasurementthanthe conventionalone.Itwasconvenienttouseitinin-situindustryinspection.