Modeling and validation of mesh-based x-ray phase imaging system

X-ray images of low-density materials, such as soft tissue, provide inherently low contrast due to their subtle attenuation differences. However, differences in phase imparted to x rays can be substantial, giving greatly improved contrast. The barrier to widespread implementation of x-ray phase imaging is that most phase techniques require high spatial coherence of the x-ray beam. A novel system has been investigated that employs a stainless steel wire mesh to produce a high-contrast structured illumination pattern which reduces the need for source coherence and complex alignments. Phase is reconstructed from distortions in this pattern due to phase-based x-ray deflection. We present a computational model utilizing ray tracing that allows us to explore its design space and to optimize our phase reconstruction algorithms. Simulation results are presented and compared with experiment for validation.