Abstract

Transport of intensity equation (TIE) provides a convenient way to retrieve phase profiles from the measurements of intensity differentials. Conventional uniform illumination TIE gives reliable phase retrieval for semi-transparent object, but is prone to low–frequency noise and circulation effect induced errors when the absorption is strong. In this paper, we demonstrate a structured illumination TIE method that simultaneously obtains both the phase and absorption images. By extracting the modulation signal that depends solely on the phase, we are able to correct for the circulation effect induced errors.

© 2015 Optical Society of America