@article{oai:niigata-u.repo.nii.ac.jp:00001528,
 author = {Suzuki, Takamasa and Yazawa, Takayuki and Sasaki, Osami},
 issue = {10},
 journal = {Applied Optics, Applied Optics},
 month = {Apr},
 note = {We describe an interferometer system that uses two separate wavelengths to measure step height. The overlapping interference images detected by a CCD camera are easily separated by an ordinary integrating-bucket method and time-sharing sinusoidal phase modulation, in which two laser diodes are alternately modulated with a sinusoidal signal. A phase map is obtained only for the laser diode into which the modulation signal is injected. In this instance, a 1-microm step height was accurately detected.},
 pages = {1972--1976},
 title = {Two-wavelength laser diode interferometer with time-sharing sinusoidal phase modulation},
 volume = {41},
 year = {2002}
}