| This dissertation presents design, implementation, and biomedical applications of a novel polarization-maintaining-fiber based phase sensitive optical low-coherence reflectometer (PS-OLCR). Using dual channels, PS-OLCR detects Angstrom/nanometer scale optical path length changes by calculating phase difference between depth resolved interference fringes. Ability to detect such small changes in optical path length at specific depths is useful in a wide variety of biomedical imaging and sensing applications. Application areas investigated in this dissertation include (i) measurement of analyte concentrations, (ii) imaging surface topography, (iii) cartilage surface response to electrical stimulation, (iv) arterial tissue response to photothermal stimulation, (v) birefringence measurement, and (vi) optical detection of neural activity. For each application, results of PS-OLCR differential phase measurements are presented. |
