Optimization of differential phase-contrast imaging setups using simulative approaches

Differential phase-contrast imaging with X-ray tubes based on Talbot Interferometry is influenced by conventional X-ray imaging setups. Parameters, which are optimized for conventional setups, may not be optimal for differential phase-contrast imaging. Therefore, there is a high potential for optimization of differential phase-contrast imaging. Quantities like visibility, contrast to noise ratio, and dose can be combined to form an objective function. For differential phase-contrast imaging, those possible objective functions are generally not known analytically and are expected to be non-linear. The optimization of differential phase-contrast is still possible as the quantities, which are necessary to form an objective function, can be obtained by a simulation. Additionally, setup parameters can be varied more purposefully within the simulation than it would be possible in an experimental setup. To take particle as well as wave contributions into account, a Monte-Carlo simulation framework and a wave field simulation framework are used. Numerical optimization procedures are an adequate approach to find optimal setups for differential phase-contrast imaging. The objective function can be obtained by numerical simulations. Hence, different optimization procedures will be evaluated and compared. Results for an optimized phase grating and an optimized analyzer grating are presented. The appropriate optimization procedure and the optimal setup depend on the intended application of the setup and the constraints which the setup parameters have to obey.