Ultra-low sensitivity to temperature low-cost optical fiber Fabry-Perot micro pressure sensor with a chitosan diaphragm

In this paper, a low-cost CDEFPI (chitosan diaphragm-based extrinsic Fabry-Perot interferometer) micro pressure sensor with high sensitivity and ultra-low temperature dependence is proposed. The chitosan diaphragm is achieved through crosslinking method via glutaraldehyde which reduces extremely the water swelling property of chitosan and improves greatly the performance of sensor. A vent hole leaving during laser heating fusion bonding process guarantees the ultra-low temperature sensitivity of the sensor. The CDEFPI pressure sensor with a sensitivity of 25.65 nm/kPa (176.86 nm/psi), a resolution of 7.8 Pa (0.001 psi), temperature sensitivity of 0.015 nm/°C, and a thermal induced pressure measurement error limited within 0.0005 kPa/°C (0.00007 psi/°C) has been demonstrated.