Simultaneous two-wavelength transmission quantitative phase microscopy with a color camera.

Department of Biomedical Engineering, Fitzpatrick Institute for Photonics, Duke University, Durham, North Carolina 27708, USA.
Optics Letters (Impact Factor: 3.39). 08/2010; 35(15):2612-4. DOI: 10.1364/OL.35.002612
Source: PubMed

ABSTRACT We present a quantitative phase microscopy method that uses a Bayer mosaic color camera to simultaneously acquire off-axis interferograms in transmission mode at two distinct wavelengths. Wrapped phase information is processed using a two-wavelength algorithm to extend the range of the optical path delay measurements that can be detected using a single temporal acquisition. We experimentally demonstrate this technique by acquiring the phase profiles of optically clear microstructures without 2pi ambiguities. In addition, the phase noise contribution arising from spectral channel crosstalk on the color camera is quantified.

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