@inproceedings{oai:niigata-u.repo.nii.ac.jp:00031064,
 author = {Sasaki, Osami and Murata, Norihiko and Akiyama, Kazuhiro and Suzuki, Takamasa},
 book = {Proceedings of SPIE - the International Society for Optical Engineering, Proceedings of SPIE - the International Society for Optical Engineering},
 month = {Sep},
 note = {Two different sinusoidal wavelength-scanning (SWS) interferometers with a SWS light source using a superluminescent laser diode are proposed for step-profile measurement and real-time distance measurement, respectively. An optical path difference (OPD) longer than a wavelength is measured from detection of sinusoidal phase- modulation amplitude Zb of the interference signal that is proportional to the OPD and the scanning width 2b. In step-profile measurement, if measurement error in the OPD obtained from Zb is smaller than a half wavelength, this measured value of the OPD is combined with a fractional value of the OPD obtained from the conventional phase of the interference signal. This combination enables us to measure the OPD longer than a wavelength with a high accuracy of a few nm. In real-time distance measurement, the amplitude Zb is kept at a specified constant value for changes of OPD by controlling the scanning width 2b of the wavelength with a feedback system. The amplitude Zb is detected by processing the interference signal with electric circuits in real-time. The value of b is easily controlled in the SWS light source, and an OPD longer than a wavelength is measured from the value of b with an accuracy of about a wavelength., Applications : Conference : Sep 1999, Pultusk, Poland},
 pages = {196--204},
 publisher = {International Society for Optical Engineering, SPIE},
 title = {Sinusoidal wavelength-scanning interferometers using a superluminescent diode},
 volume = {3745},
 year = {1999}
}