An effective attenuation coefficient for evanescent wave spectroscopy using multimode fiber
- 1 April 1990
- journal article
- research article
- Published by Taylor & Francis in Fiber and Integrated Optics
- Vol. 9 (2) , 143-151
- https://doi.org/10.1080/01468039008202901
Abstract
An attenuation coefficient for evanescent wave spectroscopy on the core of a multimode step index fiber in contact with an absorbing species is derived in terms of the range of incident angles of the meridional rays to the interface. An expression, for the fractional power outside the core as a function of incident angles is also given. Their ratio is discussed for the case of a fiber sensor having a porous cladding in contact with a gaseous absorbing species and one in which a section of cladding has been removed and replaced by an absorbing liquid.Keywords
This publication has 4 references indexed in Scilit:
- Evanescent wave absorption spectroscopy using multimode fibersJournal of Applied Physics, 1990
- Evanescent wave infrared spectroscopy of liquids using silver halide optical fibersJournal of Applied Physics, 1988
- Fiber-optic evanescent-wave methane-gas sensor using optical absorption for the 3392-μm line of a He–Ne laserOptics Letters, 1987
- Weakly Guiding FibersApplied Optics, 1971