Surface Roughness Measurement System Based on Interference Image Processing

Abstract

Inordertorealizequick,nondestructiveandautomaticmeasurementofthesurfaceroughnessofhigh accuracygaugeblock,asurfaceroughnessmeasurementsystembasedoninterferenceimage processingisstudiedout.Thesystemconsistsofaninterferencemicroscope,adigitalCCDvideo cameraandacomputer.Thegaugeblocksurfaceundertestisimaged bytheinterference microscope.TheinterferenceimageisacquiredandtransmittedtothecomputerbythedigitalCCD videocamera.Digitalimageprocessingtechnologyisusedtoextracttheedgecontourlineand midlineoftheinterferencedarkfringe.Thenthesurfaceroughnessassessparametersarecalculated out.Thetestresultsand theevaluationofuncertaintyinthemeasurementarepresented.The uncertaintyresultedfrommeasurementrepeatabilityisabout0.9nmandtheextendeduncertaintyin themeasurementisabout3nm.