Study of macro-bending biconical tapered plastic optical fiber for relative humidity sensing

The purpose of this paper is to propose and optimize plastic optical fiber (POF) probe with macro-bending biconical tapered structure for the relative humidity (RH) sensing.,In this study, the principle is the evanescent wave power modulated by the ambient humidity. The probe is fabricated by using fused biconical taper and heat-setting method and then coated with a fluorescent moisture-sensitive film.,The probe’s sensing performance can be optimized by changing the probe’s curvature radius, biconical tapered transition length and taper waist diameter. The result shows that the sensitivity of the probe is up to 1.60 and 3.40 mV/ per cent, respectively, at low humidity (10-45 per cent) and high humidity (45-90 per cent). Also, this probe has good linearity, repeatability, photostability and long-term stability.,The proposed probe can improve the sensitivity and linearity of RH sensing without complex devices, which is necessary for mass production, remote measurement and convenient operation.,POF probe with macro-bending biconical tapered structure is investigated in this paper, which is proved to be effective in improving the sensitivity and linearity.

[1]  Mikal E. Saltveit,et al.  Peanut and walnut rancidity : Effects of oxygen concentration and relative humidity , 1996 .

[2]  Harianto Rahardjo,et al.  Humidity sensing using plastic optical fibers , 2004 .

[3]  A. Malczewski,et al.  Impact of Humidity on Dielectric Charging in RF MEMS Capacitive Switches , 2009, IEEE Microwave and Wireless Components Letters.

[4]  P. Rastogi,et al.  Relative humidity sensor with optical fiber Bragg gratings. , 2002, Optics letters.

[5]  P O Fanger,et al.  Impact of indoor air temperature and humidity in an office on perceived air quality, SBS symptoms and performance. , 2004, Indoor air.

[6]  Jie Zheng,et al.  Investigation of a Macro-Bending Tapered Plastic Optical Fiber for Refractive Index Sensing , 2016, IEEE Sensors Journal.

[7]  Soumyo Mukherji,et al.  Evanescent Wave Absorption Based Fiber-Optic Sensor - Cascading of Bend and Tapered Geometry for Enhanced Sensitivity , 2015 .

[8]  F. Mitschke.  Fiber-optic sensor for humidity. , 1989, Optics letters.

[9]  Harith Ahmad,et al.  Tapered Plastic Optical Fiber Coated With Al-Doped ZnO Nanostructures for Detecting Relative Humidity , 2015, IEEE Sensors Journal.

[10]  Banshi D. Gupta,et al.  A novel probe for a fiber optic humidity sensor , 2001 .

[11]  Martin M. F. Choi,et al.  Humidity-sensitive optode membrane based on a fluorescent dye immobilized in gelatin film , 1999 .

[12]  Fauzan Ahmad,et al.  Study of a fiber optic humidity sensor based on agarose gel , 2014 .

[13]  Eduard Reithmeier,et al.  A Planar low-cost full-polymer Optical Humidity Sensor☆ , 2016 .

[14]  Hamzah Arof,et al.  Tapered fiber coated with hydroxyethyl cellulose/polyvinylidene fluoride composite for relative humidity sensor , 2013 .

[15]  L. Rockland,et al.  Saturated Salt Solutions for Static Control of Relative Humidity between 5° and 40° C. , 1960 .