Rotational-diversity phase estimation from differential-interference-contrast microscopy images.

C Preza

doi:10.1364/josaa.17.000415

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Rotational-diversity phase estimation from differential-interference-contrast microscopy images.

C Preza

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Abstract

An iterative phase-estimation method for the calculation of a specimen's phase function or optical-path-length (OPL) distribution from differential-interference-contrast (DIC) microscopy images is presented. The method minimizes the least-squares discrepancy measure by use of the conjugate-gradient technique to estimate the phase function from multiple DIC images acquired at different specimen rotations. The estimate is regularized with a quadratic smoothness penalty. Results from testing the method with simulations and measured DIC images show improvement in the estimated phase when at least two rotationally diverse DIC images instead of a single DIC image are used for the estimation. The OPL of a cell that is estimated from two DIC images was found to be much more reliable than the OPL computed from single DIC images (which had a coefficient of variation equal to 15.8%).

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Computer Simulation Microscopy, Interference Models, Theoretical Rotation Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.

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C Preza. 2000. Rotational-diversity phase estimation from differential-interference-contrast microscopy images.. https://doi.org/10.1364/josaa.17.000415

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