Spectroscopic study of ds/dT in commercial filter by using the thermal lens technique

Abstract

In this work we report on the use of the Thermal Lens method in a spectroscopic form to investigate the dependence of the thermo-optical properties with the probe beam wavelength in a RG -610 commercial filter close to the absorption maximum (around 650 nm). The measurements were performed using a tunable dye laser as probe source and an Ar + laser at 514 nm as excitation one. Our results exhibit a strong dependence of the temperature coefficient of the optical path length change with the probe wavelength.