Ellipsometry with randomly varying polarization states

摘要: We show that, under the right conditions, one can make highly accurate polarization-based measurements without knowing absolute polarization state of probing light field. It is shown that light, passed through a randomly varying birefringent material has well-defined orbit on Poincar sphere, which we term generalized state, preserved. Changes to then be used in place states up measure change due sample investigation. illustrate usefulness this analysis approach by demonstrating fiber-based ellipsometry, where probe unknown, and, yet, ellipsometric angles investigated (Ψ and Δ) are obtained with an accuracy comparable conventional ellipsometry instruments measuring changes state.