Vol. 30, Issue 4, pp. 503-508 (2000)

Abstract

The sol-gel-derived materials can be used in construction of various optoelectronic devices, including optodes of fiberoptic sensors. The porous matrices provide excellent media for a variety of organic and inorganic compounds, which can serve as detectors. They can work in various environments with different refractive indices. We report on the influence of the refractive index of external media on the overall performance of the fiberoptic chemical microsensors. Especially, the sensors based on the intensity measurement are influenced by the refractive index of the environment The application of the sol-gel thin film as a protective layer of the microoptode is discussed. The light intensity angular distribution was examined for both the bare fiber tip, as well as for the tip covered with a sol-gel layer. The magnitude of the microsensor response signal was measured, as well. A smaller signal decrease was observed for the microoptode covered by a sol-gel. A possible application of the method described for a fiberoptic oxygen microsensor is discussed.