Microestruturas em fibras óticas e estruturas planares gravadas por microusinagem com laser de femtosegundos: controle, produção e caracterização

Abstract

The present work describes the manufacture of microstructures produced with femtosecond (fs) ultrashort pulse laser in transparent planar structures and optical fibers. The general objective of the research is the production and characterization of these microstructures through the analysis of the recording parameters. This work consists in the development of movement programs for the manufacture of different microstructures, and in exhaustive tests with changes of the recording parameters. The methodologies employed for the manufacture of microcavities in transparent planar structures are: micro-machining based on direct laser exposure ablation and laser exposure micro-machining followed by chemical corrosion (FLICE). The productions of lines, channels and areas in planar structures are described. For optical fiber micromachining the methodology used the direct ablation by laser exposure. Using the direct ablation methodology, two techniques were developed to obtain different profile cavities that employ different optical fiber movement programs. The results obtained by these different techniques are microcavities with U and V-shaped side profiles. The microcavities obtained in planar structures and optical fibers were applied as force, refractive index and temperature sensors, based on intensity and wavelength demodulation. The results obtained in this work, originate in the characterizations performed for each of these experimental arrangements, demonstrate the feasibility of manufacturing these microstructures used in sensors.