We propose to modify a commercial DIC microscope for operation in the deep UV region (e.g., 254 nm). At these shorter wavelengths, the diffraction limit is already half of that in the visible region. One would expect the resolvable dimensions to be proportionally smaller. More importantly, UV light approaches the absorption bands of most common chemical species. The well-known Kramers-Kronig relationship predicts that the refractive index of the species will increase substantially near an absorption band. Since DIC is based on differences in optical paths, the contrast for visualizing the species will be greatly increased. We expect that switching to the UV region will allow visualization of chemical structures and transformations at the 10 nm length scale for most catalysts and reactants.
Mentor: Ning Fang, Ames Laboratory Associate and Assistant Professor, Iowa State University