Studies of an optical fibre displacement sensor

Abstract

Various authors have described optical fibre sensors for measuring displacement (and pressure) based upon the measurement of light intensity reflected from a displaced mirror surface. This paper represents a study of thekey design parameters of such a sensor based upon a simple theoretical model plus experimental measurements. The results indicate the potential for very high performance from such sensors, including a noise limited displacement resolution in the region of 1 nm and a typical dynamic range of measurement from 20 to 500 μm.