@article{duncan11a,
  author = {Donald D. Duncan and David G. Fischer and Amanda Dayton and Scott A. Prahl},
  title = {Quantitative {C}arr{\'e} Differential Interference Contrast Microscopy to Assess Phase and Amplitude},
  journal = {J. Opt. Soc. Am. A},
  year = {2011},
  pages = {1297-1306},
  volume = {28},
  url = {https://omlc.org/~prahl/pubs/pdfx/duncan11a.pdf},
  abstract = {We present a method of using an un-modified differential interference contrast microscope to acquire quantitative information on scatter and absorption of thin tissue samples. A simple calibration process is discussed that uses a standard optical wedge. Subsequently we present a phase-stepping procedure for acquiring phase gradient information exclusive of absorption effects. The procedure results in two-dimensional maps of the local angular (polar and azimuthal) ray deviation. We demonstrate the calibration process, discuss details of the phase-stepping algorithm, and present representative results for a porcine skin sample.},
}