Title :
Controllable in-line UV sensor using a side-polished fiber coupler with photofunctional polymer
Author :
Yoon, Jong-Kuk ; Seo, Gyoo-Won ; Cho, Kang-Min ; Kim, Eung-Soo ; Kim, Sung-Hoon ; Kang, Shin-Won
Author_Institution :
Dept. of Sensor Eng., Kyungpook Nat. Univ., Taegu, South Korea
fDate :
6/1/2003 12:00:00 AM
Abstract :
A novel ultraviolet (UV) sensor using evanescent field coupling between single-mode-polished fiber and photochromic dye-dispersed polymer waveguide was demonstrated. It was found that resonance wavelength shifts occurred due to variations in the refractive index of the photochromic dye-dispersed polymer waveguide relative to UV intensities. A spiroxazine dye was chosen as the overlay material because of its photochromic isomerization induced by UV irradiation. The wavelength responses of these sensors by UV exposure power were measured 0.18 and 0.25 nm/mW when UV was exposed for 5 and 10 s, respectively. The recovery time for the sensor was independent of UV exposure power, and 80% recovery time was shown 90 s.
Keywords :
dyes; fibre optic sensors; filled polymers; isomerisation; optical fibre couplers; optical planar waveguides; optical polymers; optical sensors; photochromism; refractive index; 10 s; 5 s; 90 s; UV exposure power; UV intensities; UV irradiation; controllable in-line UV sensor; evanescent field coupling; overlay material; photochromic dye-dispersed polymer waveguide; photochromic isomerization; photofunctional polymer; recovery time; refractive index variations; resonance wavelength shifts; side-polished fiber coupler; single-mode-polished fiber; spiroxazine dye; ultraviolet sensor; wavelength responses; Optical fiber couplers; Optical fiber polarization; Optical fiber sensors; Optical planar waveguides; Optical refraction; Optical sensors; Optical waveguides; Photochromism; Planar waveguides; Polymers;
Journal_Title :
Photonics Technology Letters, IEEE
DOI :
10.1109/LPT.2003.811341
