An improved phase retrieval algorithm for X-ray in-line phase-contrast imaging

摘要

Phase contrast imaging technique has been improved promptly in recent years. Among these techniques in-line phase contrast imaging is widely used. Various algorithms for in-line phase retrieval have been proposed so far such as TIE (transport of intensity equation), CTF (contrast transfer function), first Born-approximations, GSF (Gerchberg-Saxton-Fienup) and etc. Bronnikov's algorithm (BA) is a type of linear algorithm that is simple and efficient. But it can only be used for no absorption situations. In this paper an improved algorithm based on BA is presented. The approach adds a △＜(ψ)_((x,y)) to the phase map (ψ)_(b(x,y)) retrieved by BA to make the reconstructed phase map more precise. Further, the approach is evaluated on simulated images and confirmed to be accurate at higher absorption rates.