Laser-induced activation of stearin transparency

The time delay in the initial stage of penetration of intense laser radiation into stearin that strongly scatters light has been experimentally detected. This phenomenon, which occurs during the melting of stearin, is explained by the lengthy breakdown process of its irregular spatial structure. It is assumed that the transition of stearin from a superheated, strongly scattering solid state to a liquid occurs via activation transitions over metastable states. A model description is given of the penetration kinetics of the radiation as a consequence of homogenization of the medium. © 2004 Optical Society of America