On the use of flat-fields for tomographic reconstruction

Area of Science:

• Medical Imaging
• Physics
• Materials Science

Background:

• Quantitative tomographic imaging requires minimizing reconstruction artifacts.
• Detector imperfections and beam inhomogeneity cause significant reconstruction bias, such as ring artifacts, in synchrotron-based imaging.
• Temporal variations in beam characteristics further exacerbate these issues.

Purpose of the Study:

• To propose a method for estimating local incident beam intensity per projection during tomographic scans.
• To develop a technique that corrects for detector imperfections and beam variations without modifying the data acquisition process.
• To improve the accuracy of quantitative tomographic reconstructions.

Main Methods:

• Exploiting actual flat-field images and sinogram borders to construct an instantaneous, detector-wide flat-field.
• Implementing a fast and simple data processing treatment.
• Assessing performance using residuals (difference between reconstructed and actual projections).

Main Results:

• The proposed method effectively estimates instantaneous detector-wide flat-fields.
• Artifacts, particularly ring artifacts, are significantly reduced in the reconstructed images.
• Residual analysis confirms the accuracy and benefit of the developed procedure.

Conclusions:

• The presented method offers a computationally efficient and effective solution for correcting beam-related artifacts in tomographic imaging.
• This approach enhances the quality and reliability of quantitative tomographic data, especially from synchrotron sources.
• The technique is readily applicable and improves the fidelity of reconstructed images.