Enhanced sensitive fiber-optic sensor with double pass evanescent field absorption

Abstract

A fiber optic sensor with double pass evanescent field absorption from an unclad U-bent multimode optical fiber is presented. One end of the fiber is polished to form an angled-tip, whereas the other end is flat polished. Evanescent field absorption in the bending region undergoes further absorption as it reflects back from the fiber tip-air interface thus, enhancing higher sensitivity of the sensor. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett.