title: Real-time displacement measurement with a two-wavelength sinusoidal phase-modulating laser diode interferometer.
abstract: A two-wavelength interferometer that uses two separate modulating currents with different phases but the same frequencies to detect a greater degree of object displacement in real time is proposed and demonstrated. The measurement error was 57 nm, roughly 1/80 of the synthetic wavelength. We have confirmed that this modulating technique enables us to equip our prototype interferometer with a simple feedback-control system that eliminates external disturbance.
authors.affiliation: Faculty of Engineering, Niigata University, 8050 Ikarashi 2, Niigata 950-2181, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Suzuki
authors.forename: K
authors.initials: K
authors.lastname: Kobayashi
authors.forename: O
authors.initials: O
authors.lastname: Sasaki