Quantitative DIC microscopy using an off-axis self-interference approach.

G. R. Harrison Spectroscopy Laboratory, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Optics Letters (Impact Factor: 3.18). 07/2010; 35(14):2370-2. DOI: 10.1364/OL.35.002370
Source: PubMed

ABSTRACT Traditional Normarski differential interference contrast (DIC) microscopy is a very powerful method for imaging nonstained biological samples. However, one of its major limitations is the nonquantitative nature of the imaging. To overcome this problem, we developed a quantitative DIC microscopy method based on off-axis sample self-interference. The digital holography algorithm is applied to obtain quantitative phase gradients in orthogonal directions, which leads to a quantitative phase image through a spiral integration of the phase gradients. This method is practically simple to implement on any standard microscope without stringent requirements on polarization optics. Optical sectioning can be obtained through enlarged illumination NA.


Available from: Zahid Yaqoob, Jun 03, 2015
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