Monolithically integrated optical displacement sensor based on triangulation and optical beam deflection.
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.
Higurashi
E
E
NTT Opto-electronics Laboratories, 3-9-11 Midori-cho, Musashino-shi, Tokyo 180-8585, Japan. eiji@ilab.ntt.co.jp
Sawada
R
R
Ito
T
T