Document Type



Available under a Creative Commons Attribution Non-Commercial Share Alike 4.0 International Licence


Electrical and electronic engineering

Publication Details

Optics Letters, Vol.36, no. 10, May 15, 2011

This paper was published in Optics Letters and is made available as an electronic reprint with the permission of OSA. The paper can be found at the following URL on the OSA website:


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Using a small-core single-mode fiber (SCSMF), a novel relative humidity (RH) sensor based on an SMF28-SCSMFSMF28 fiber structure was proposed in this paper. By depositing a humidity sensitive material, such as poly (ethylene oxide) (PEO) on the bare SCSMF fiber, the proposed structure can act as an RH sensor with high sensitivity. Experiments demonstrated that the proposed RH sensor with PEO coating can achieve a sensitivity of 430nm per relative humidity unit (RHU) in the RH range from 80% to 83% RH and a sensitivity of 50nm per RHU in the RH range from 83% to 95% RH.



Science Foundation Ireland under grant 07/SK/I1200, the Irish Research Council for Science, Engineering and Technology, and Marie-Curie Actions under FP7