Transverse force sensitivity of photonic crystal fibres

Four types of photonic crystal fibres (PCFs) with different birefringence characteristics were evaluated and cross-compared on their corresponding sensitivities to transverse force as a function of fibre orientation and the magnitude of the applied external force. The results obtained show that PCFs of low birefringence are more sensitive than those of high birefringence (Hi-Bi) although the former require a longer length to achieve a similar level of birefringence. Compared to conventional Hi-Bi fibres (e.g. Panda and Bow-Tie fibres), PCFs have demonstrated much lower temperature sensitivity and this suggests that they are well suited to measure pressure, force, and mass in real time when temperature varies by using a fibre loop mirror (FLM) configuration.