Effect of water absorption on the stability of a polymer based Young's interferometric sensor

In this work the refractive index change of a polymer (Ormocer) based waveguide interferometer under the influence of water absorption was analyzed. The water absorption caused refractive index change was up to 104. After half an hour contacting with deionized water a pseudo-equilibrium state was reached and the response of the sensor tended to be stabilized. We performed refractive index measurement with glucose water dilutions. The measured refractive index change showed a linear relationship with the glucose concentration.