Fibre optic intra cavity spectroscopy - combined ring down and ICLAS architectures usign fibre lasers

摘要

This paper discusses using the multi-pass techniques of cavity ring-down and intracavity spectroscopy (ICLAS) to increase the sensitivity of optical fibre gas sensors. An experimental fibre loop ystem has been built with standard optical fibre components and a micro-optic cell. An erbium amplifier is included in the fibre loop. For the cavity ring-down the amplifier allows the fibre loop to mimic the high finesse cavities used for conventional, bulk optic ring-down by compensating for the system losses. The amplifier acts as the gain medium for the intracavity set-up.