Interferometria speckle com lasers de diodo multimodo para análise de materiais e dispositivos

Abstract

In this work we will develop a new method focused on the caracterization of thermal lenses effect in photonic materials used as active media in lasers design. This method is based on electronic speckle pattern interferometry (ESPI) using two multimode diode lasers tuned to different frequencies. Adjusting this difference we can achieve an appropriate resolution to measure the variability generated within the curvature radius of the wavefront due to thermal lens effect. For our experiments we chose a vitreous sample of calcium aluminate doped with 4% erbium and incident pump powers ranging to 1.76mW. The diode lasers were tuned to have a contour interval of around 120m. With addition in power absorbed by the sample, we observed a decrease in the curvature radius incident on the camera due to increased power of the thermal lens generated. Through a paraxial of the wavefront, an approach was made to obtain the values of the lenses for each configuration, with focal lengths ranging from 131.39 mm to 42.76 mm.

Design, simulation, and fabrication of an ingestible capsule with gastric balloon for obesity treatment

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