Sinogram cleaning procedure for optical diffraction tomography

Abstract

Limited angle optical diffraction tomography is a technique that allows for non-destructive and quantitative analysis of biological samples directly from Petri dishes and microscope slides. Recently, a new reconstruction method, called Generalized Total Variation Iterative Constraint (GTVIC), was proposed. It is an iterative modular technique that calculates the reconstruction without the errors that are otherwise present due to limited angular range of projections. Unlike other similar techniques, GTVIC is dedicated to biological structures that have non-piecewise constant refractive index distribution. However, GTVIC is sensitive to local deviations of the immersion refractive index from its nominal value. Such deviations are present due to e.g. dust or cellular debris in the measurement volume. Therefore, we propose a method for preprocessing of a sinogram that numerically removes unwanted objects from the measurement volume without affecting the investigated object and its diffraction pattern. The described method is found useful in any tomographic algorithm that utilizes support constraint in the reconstruction process.