Interferometric laser detection of nanomechanical perturbations in biological media under ablation conditions

Abstract

This article has to do with the development of a reliable and sensitive non-invasive laser technique for assessing damage of structures and systems involved in laser ablation processes. The optical response of a Michelson Interferometer in combination with a Measuring Reflectance System has been analyzed in order to identify the stability of the mechanical properties of the sample, the physical perturbations associated with the systems and the environment where the target is contained. This test includes the use of a cyan laser system with 10 mW at 488 nm wavelength as optical source. We found out that with the inclusion of an optical feedback in a sensing system it is possible to determine the modification of the physical properties exhibited by a biological medium under sharp ablation conditions with a high accuracy degree. The results reported in this research have potential applications related to the amount of light intensity that can be tolerated by human tissue. A wide array of disciplines, such as medicine, mechanical industry and optical instrumentation can benefit from this ultrafast optical feedback for controlling high intensity laser signals. Collateral damage of tissue around the laser irradiated zones can be reduced by using intelligent lasers systems with ultra-short temporal response. © 2011 Published under licence by IOP Publishing Ltd.