ABSTRACT
Light scattering in biological tissues originates from the tissue inhomogeneities such as cellular organelles, extracellular matrix, and blood vessels. Components of organelles can also scatter light. Finite-difference time-domain simulations provide means to study spectral and angular features of light scattering by arbitrary particles of complex shape and density. Not only does light scattered by cell nuclei have a characteristic angular distribution peaked in the near-backward directions, but it also exhibits spectral variations typical for large particles. This information has been used to study the size and shape of small particles such as colloids, water droplets, and cells. The oscillatory behavior of light scattered by a cell nucleus exhibits frequency dependence with size. This was used to obtain the size distribution of the nuclei from the spectral variation of light back-scattered from biological tissues. The Confocal light absorption and scattering spectroscopic microscope is capable of collecting both spatial and spectroscopic information based on light scattering by submicroscopic biological structures.
