Use of common path phase sensitive spectral domain optical coherence tomography for refractive index measurements

We report the use of a common path phase sensitive spectral domain optical coherence tomography setup for the measurement of the refractive index (RI) of a biomimetic material (glucose solution in water having intralipid as the scattering medium) and a single biological cell (keratinocyte). The RI of glucose solutions could be measured with a precision of -0.00015, which corresponds to a precision of -2nm in the optical path length measurement in our setup. The precision obtained in the measurement of the RI of a single keratinocyte cell was -0.0004