Inverse problems in X-ray phase retrieval and tomography

Session

invited talks

Apr 4, 2019, 9:00 AM

Workshop room, 5th floor (LINXS)

3. Doga Gursoy, Northwestern University & Argonne National Lab.

4/4/19, 9:10 AM

Ptycho-tomography: An emerging lensless microscopy technique for imaging materials at the nanoscale

The increasing availability of coherent light sources at short wavelengths from the extreme ultraviolet to the hard x-ray regime has paved the way for widespread use of coherent diffraction imaging (CDI) techniques in the past decade. In contrast to classical microscopy, CDI does not require an...

1. Max Langer, Creatis, INSA Lyon, France

4/4/19, 9:40 AM

Some methodological contributions to X-ray phase contrast imaging

I present some of our methodological contributions to X-ray phase contrast imaging. Phase retrieval often suffers from noise in the low spatial frequencies. We proposed a prior on the imaged object based on an attenuation image to regularise the low spatial frequencies in the retrieved phase. For the experimental setup, we...

2. Marcus Carlsson, Lund University

4/4/19, 10:10 AM

PhaseLift, possibilities and challenges.

The phase retrieval problem is ill posed, and most phase retrieval algorithms stabilize inversion via additional assumptions on the support of the object. These algorithms come without guarantee of convergence, and it is a problem in practice. PhaseLift is a new (2013) algorithm which is based on a completely different approach, and it stabilizes the...

8. Per Christian Hansen, DTU Compute

4/4/19, 11:00 AM

Convergence and Non-Convergence of Algebraic Iterative Reconstruction Methods

Algebraic Iterative Reconstruction methods – such as ART (Kaczmarz), SART, and SIRT produce good results for underdetermined problems, and they can easily incorporate non-negativity and box constraints.
When AIR methods are implemented on GPU-accelerated systems with a focus on computational efficiency, different...

5. Viktor Nikitin, Lund University

4/4/19, 11:35 AM

Fast reconstruction in dynamic tomography

6. Daniel Pelt, CWI Amsterdam

4. Doga Gursoy, Northwestern University, USA

7. Jonas Adler, KTH Stockholm