Design and Manufacturing Relative Humidity Sensor By Photonic Crystal Fibers
Photonic crystal fiber interferometers have attained great importance in recent times due to the simple fabrication process involved and excellent sensing performance. A photonic crystal fiber interferometer that operates in reflection mode for humidity sensing is presented in this work. The fabrication of the sensor head is therefore simple since it only involves cleaving and splicing. The all-silica nature of the device has the potential for many applications. The photonic crystal fiber interferometer response is observed for a range of humidity values from (35% RH to 90% RH), the position of the interference peaks is found to be shifted to longer wavelength with humidity increasing. In this work, a different length of PCFs are used, and the maximum humidity sensitivity of (5.180 pm / %RH) is achieved with (4.5cm) PCF length. The photonic crystal fiber interferometer has the advantage that it does not require the use of any hygroscopic material.