Diffraction Tomography Reconstruction Research Articles

A method for assessing the fidelity of optical diffraction tomography reconstruction methods using structured illumination

A fundamental challenge in 3D tomographic reconstruction is the difficulty of obtaining ground truth about test objects with which to assess the fidelity of the 3D reconstruction. We present a method that provides such a quantitative metric of the accuracy of the three dimensional reconstruction for optical tomography. The method relies on spatial light modulation of the illumination beam through the sample and numerical back-propagation of the phase conjugated experimentally measured optical field through the 3D reconstruction of the object. The fidelity of this reconstruction provides a quantitative measure of the accuracy of the 3D reconstruction without direct access to the ground truth about the 3D object.

Enhanced 3D spatial resolution in quantitative phase microscopy using spatially incoherent illumination

We describe the use of spatially incoherent illumination to make quantitative phase imaging of a semi-transparent sample, even out of the paraxial approximation. The image volume electromagnetic field is collected by scanning the image planes with a quadriwave lateral shearing interferometer, while the sample is spatially incoherently illuminated. In comparison to coherent quantitative phase measurements, incoherent illumination enriches the 3D collected spatial frequencies leading to 3D resolution increase (up to a factor 2). The image contrast loss introduced by the incoherent illumination is simulated and used to compensate the measurements. This restores the quantitative value of phase and intensity. Experimental contrast loss compensation and 3D resolution increase is presented using polystyrene and TiO(2) micro-beads. Our approach will be useful to make diffraction tomography reconstruction with a simplified setup.

Multispectral intensity diffraction tomography reconstruction theory: quasi-nondispersive objects

A multispectral intensity diffraction tomography (I-DT) reconstruction theory for quasi-nondispersive scattering objects is developed and investigated. By "quasi-nondispersive" we refer to an object that is characterized by a refractive index distribution that is approximately nondispersive over a predefined finite temporal frequency interval in which the tomographic measurements are acquired. The scanning requirements and measurement data are shown to be different than in conventional I-DT. Unlike conventional I-DT that requires intensity measurements on a pair of detector planes for each probing wave field, this new method uses measurements on a single detector plane at two frequencies. Computer simulation studies are conducted to demonstrate the method.

Numerically robust minimal‐scan reconstruction algorithms for diffraction tomography via radon transform inversion

AbstractIt is widely believed that measurements from a full angular range of 2π are generally required to exactly reconstruct a complex‐valued refractive index distribution in diffraction tomography (DT). In this work, we developed a new class of minimal‐scan reconstruction algorithms for DT that utilizes measurements only over the angular range 0 ≤ ϕ ≤ 3π/2 to perform an exact reconstruction. These algorithms, referred to as minimal‐scan estimate‐combination (MS‐E‐C) reconstruction algorithms, effectively operate by transforming the DT reconstruction problem into a conventional x‐ray CT reconstruction problem that requires inversion of the Radon transform. We performed computer simulations to compare the noise and numerical properties of the MS‐E‐C algorithms against existing filtered backpropagation‐based algorithms. © 2002 Wiley Periodicals, Inc. Int J Imaging Syst Technol 12, 84–91, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ima.10014

Diffraction tomography reconstruction algorithms for quantitative imaging of phase objects.

A new reconstruction algorithm for phase-object imaging is proposed that is based on the principle of diffraction tomography and utilizes the Fourier transformation property of a finite-size phase object. From the measured scattered intensity, the imaginary part of the Fourier transform of the object can be extracted, and the three-dimensional structure of the object can be reconstructed. Numerical simulations show that the algorithm also can be used for a weak absorption object if the phase shift is much larger than the absorption.