Full-aperture long focal-length measurement based on divergent beam

摘要

Anewmethodforlongfocal-lengthmeasurementsisproposed.Inthismethod,weemploydivergentbeamandtwoRonchigratingsofdifferentperiods,asthealternativetocollimatedbeamsandtwoidenticalgratingsintraditionalmethod,torealizeachievehigheraccuracy.Moreover,withdivergentbeam,thefull-aperturemeasurementiseasilyrealizedwhendetectlargediameterlens.Theexperimentsdemonstratedtheproposedmethodfeatureshighaccuracyandrepeatability...