ABSTRACT
The authors start with a brief description of the various ways that the light interacts with matter, in particular, with the applications of lasers in biology and medicine based on the use of numerous phenomena associated with various effects of interaction of light with biological objects. As the biospeckle phenomenon is characteristic of biological samples, they present a description of the cells that are the main components of living tissues, and the authors analyze their optical properties. An analysis by Briers, where he demonstrates the equivalence among time-varying speckle phenomenon, laser Doppler velocimetry, and photon correlation spectroscopy. So, the authors discuss other phenomena, such as turbulence and diffusion that introduce biospeckle fluctuations. He present a brief description of biological tissues. The biospeckle can be described in terms of the Doppler effect and frequency variations, but others effects as turbulence and diffusion can also be present and must be considered. Turbulence and diffusion that introduce biospeckle fluctuations are also discussed.
