| The imaging and identification of microstructures within biological specimens is of great interest in medicine and biology. A specimen can contain adjacent structures, both of which could be highly transparent, thus greatly reducing the contrast achievable by conventional microscopic techniques. Standard methods to deal with such structur include applying a stain or dye to the sample which only attaches to the structure of interest, or phase-contrast methods. These methods typically require very thin samples or the addition of external material to the sample, both of which limit in-vivo use. An alternate method is to perform measurements on the index of refraction of localized structures and use that information to determine locations and boundaries. This method eliminates the need for a dye or other external contrast medium.; In this thesis, a proof-of-concept prototype was designed and constructed to evaluate the feasibility of utilizing index of refraction as a contrast medium in biological samples. A short-coherence light source and interferometer was utilized to perform optical path length measurements of a multilayered phantom sample in tandem with confocal techniques designed to determine position. The resulting data were used to determine the index of refraction of the individual layers within the sample. |
