Miniature optical fibre ultrasonic hydrophone using a Fabry-Perot polymer film interferometer

摘要

An optical fibre hydrophone for the measurement and detection of ultrasound is described. The active sensing element consists of a low finesse Fabry-Perot polymer film interferometer bonded to the tip of an optical fibre, of 50 /spl mu/m core diameter and 0.25 mm outer diameter. Sensitivity was found to be 114 mV/MPa with an acoustic noise floor of 15 kPa over a 25 MHz bandwidth.