title: Monolithically integrated optical displacement sensor based on triangulation and optical beam deflection.
abstract: A monolithically integrated optical displacement sensor based on triangulation and optical beam deflection is reported. This sensor is simple and consists of only a laser diode, a polyimide waveguide, and a split detector (a pair of photodiodes) upon a GaAs substrate. The resultant prototype device is extremely small (750 microm x 800 microm). Experiments have shown that this sensor can measure the displacement of a mirror with resolution of better than 4 nm. Additionally, we have experimentally demonstrated both axial and lateral displacement measurements when we used a cylindrical micromirror (diameter, 125 microm) as a movable external object.
authors.affiliation: NTT Opto-electronics Laboratories, 3-9-11 Midori-cho, Musashino-shi, Tokyo 180-8585, Japan. eiji@ilab.ntt.co.jp
authors.forename: E
authors.initials: E
authors.lastname: Higurashi
authors.forename: R
authors.initials: R
authors.lastname: Sawada
authors.forename: T
authors.initials: T
authors.lastname: Ito