Weak pressure sensor based on photonic crystal fibers

In order to analyze the characteristics of photonic crystal fiber under weak pressure,the relationship between the birefringence and the pressure was simulated with the finite element method.The birefringence in photonic crystal fibers is more sensitive than that in conventional step-index fibers,but the birefringence change caused by the weak pressure is less and it is difficult to measure the variation of pressure by Bragg wavelength measurement.The polarization dependent loss was used to measure the birefringence change caused by the external weak pressure.The simulated results show that the measured sensitivity can reach 0.75dB/MPa.