Intensity measurement based temperature-independent strain sensor using a highly birefringent photonic crystal fiber loop mirror

A fiber-optic strain sensor is demonstrated by using a short length of highly birefringent photonic crystal fiber (HiBi-PCF) as the sensing element inserted in a fiber loop mirror (FLM) Due to the ultralow thermal sensitivity of the HiBi-PCF the proposed strain sensor is inherently insensitive to temperature When a distributed-feedback (DFB) laser passes through the FLM the output power is only affected by the transmission spectral change of the FLM caused by the strain applied on the HiBi-PCF Based on intensity measurement an optical power meter is adequate to deduce the strain information and an expensive optical spectrum analyzer (OSA) would not be needed (C) 2010 Published by Elsevier BV