A Study of Optical Micro-bottle Resonator Humidity Sensor

Abstract

This experiment reports the fabrication of the optical Micro-bottle Resonator (MBR) as a relative humidity (RH) sensor. The MBR is fabricated via the “soften-and-compress” method to create the bottle-shaped with diameter Db = 175 um. The MBR is then optically excited using a 8 μm microfiber and was found to have a Q Factor of >105. The MBR was then employed as a humidity sensor with the RH level percentage range between 40% to 100% and the performance is compared with a non MBR microfiber. The MBR sensor was found to have a sensitivity of 0.2973 dBm/%, linearity >90% and and is superior to the bare microfiber in all measured parameters. The MBR humidity sensor was also found to have good repeatability and stability over a period of 60 seconds compare to bare microfiber.