title: Wide measurement range scanning heterodyne interferometer utilizing astigmatic position sensing scheme.
abstract: A scanning heterodyne I/Q-interferometer scheme is proposed to overcome phase ambiguity caused by the periodic nature of its phase-dependent signal. A position sensing scheme using an astigmatic method in the confocal arrangement has been interfaced to the interferometer to retrieve the real phase value during a scanning process. The experimental results show that the vertical measurement range can be expanded up to 16 μm. The potential of this interferometer on the scanning microscopy of a rough surface is discussed.
authors.affiliation: Department of Physics, Sogang University, One Sinsu-Dong, Mapo-Gu, Seoul, 121-742, Korea.
authors.forename: Youngkyu
authors.initials: Y
authors.lastname: Park
authors.forename: Kyoung-Eop
authors.initials: KE
authors.lastname: Kim
authors.forename: Seong-Jin
authors.initials: SJ
authors.lastname: Kim
authors.forename: June-Gyu
authors.initials: JG
authors.lastname: Park
authors.forename: Young-Hun
authors.initials: YH
authors.lastname: Joo
authors.forename: Bu Hyun
authors.initials: BH
authors.lastname: Shin
authors.forename: Seung-Yop
authors.initials: SY
authors.lastname: Lee
authors.forename: Kyuman
authors.initials: K
authors.lastname: Cho