Fault Tolerant Algorithm for Structured Illumination Microscopy with Incoherent Light

Abstract

In this contribution we present a new algorithm for structured illumination microscopy with incoherent light. Existing algorithms for determining the contrast values of the focal depth response require a high accurate phase shift of the fringe pattern illumination. The presented algorithm, which is robust against inaccurate phase shift of the fringe pattern, reduces significantly the requirements for the phase shift and consequently the costs of the microscope. The new algorithm was tested by a preliminary experiment, whereby the grating was shifted by an elastic guided micro-motion mechanism employing a low-cost stepper motor replacing the conventional expensive piezo drive. The determined focal depth response is very smooth and corresponds very well to the theoretical focal depth response.

Application of Two-dimensional Fourier Transform in Structured-illumination Microscopy

“…5,6 The possible depth of filed may be larger than 100 times the Rayleigh depth of field. 7 The traditional SIM system share all the common operations: projecting a patterned illumination on the sample, phase-shifting the pattern in accurate steps over the specimen, determining the contrast for all pixels, shifting the specimen in steps of z through focus, extracting the focal depth response (FDR) for all pixels and determining the focal position of each pixel to generate the topography of the specimen. The measurement system requires two PZT stages to achieve a high precise phase shifting and vertical scanning respectively.…”