Video-rate optical low-coherence reflectometry based on a linear smart detector array.

Abstract

A low-coherence reflectometer based on a conventional Michelson interferometer and a novel silicon detector chip that allows parallel heterodyne detection is presented. Cross-sectional images of $64\times 256$ pixels covering an area of $1.92 \mathrm{mm}\times 1.3 \mathrm{mm}$ are acquired at video rate and with a sensitivity close to the shot-noise limit. Applications in surface profiling and thickness measurement are demonstrated.