Development of X-ray phase CT with a hybrid configuration of Lau and Talbot-Lau interferometers.

X-ray phase computed tomography (CT) is used to observe the inside of light materials. In this paper, we report a new study to develop and test a laboratory assembled X-ray phase CT system that comprises an X-ray Lau interferometer, a rotating Mo anode X-ray tube, and a detector with high spatial resolution. The system has a high spatial resolution lower than 10 µm, which is evaluated by differentiating neighbouring carbon fibres in a polymer composite material. The density resolution is approximately 0.035 g/cm3, which enables to successfully distinguish the high-density polyethylene (HDPE, 0.93 g/cm3) from the ultra-low-density polyethylene (ULDPE, 0.88 g/cm3) in the sample. Moreover, the system can be switched to operate on another mode based on a Talbot-Lau interferometer that provides a wider field of view with a moderate spatial resolution (approximately 100 µm). By analyzing sample images of the biological, this study demonstrates the feasibility and advantages of using hybrid configuration of this X-ray phase CT system.