Spectral Domain Phase Microscopy (SDPM) has been reported in the literature as a functional extension to low coherence interferometry which enables nanoscale measurement of a scatter's displacement. The signal in SDPM is generated from structural images that lack molecular specificity. This report investigates the expansion of phase analysis to fluorescence self interference signals to provide functional information about a sample. Spectral Domain Fluorescence Coherence Phase Microscopy (SDFCPM) is demonstrated for nanoscale resolution motion detection of fluorescent particles with an SNR limited resolution of ~10nm. This report demonstrates the feasibility of combining phase processing with fluorescence self interference, which may be useful for future applications such as cell rheology.

Schematic of SDFCPM system topology combining a common-path interferometer (left) and a spectrometer (right).

Reference

A. St. Quintin, L. K. Merhi, M. V. Sarunic, “Spectral Domain Fluorescence Coherence Phase Microscopy”, Applied Optics Vol. 50 Issue 12, pp.1798-1804 (2011). Impact Factor 1.410.