Optical Fiber-Top Microcavity Sensor for CO2 Detection

J. Wu, M-J Yin, K. Taeuber, A. Dani, R. Guterman, J. Yuan, A.P. Zhang, H-Y Tam
The Hong Kong Polytechnic University,
Hong Kong

Keywords: fiber-optic sensor, CO2 sensor, optical microfabrication


In the paper, we present a miniature fiber-optic CO2 sensor by in-situ printing of a special polymer Fabry-Pérot (FP) microcavity on the end facet of standard single-mode optical fiber. A photo-crosslinkable poly(ionic liquid)s (PILs) with high CO2 adsorption capability has been developed to fabricate the polymer optical microcavity via an optical 3D µ-printing technology. Experimental results show that such an optical CO2 microsensor has very high sensitivity and fast response and thus is very promising for environment and exhaust gas monitoring applications.