A device and method of the present disclosure provides large field-of-view Talbot-Lau phase contrast CT systems up to very high X-ray energy. The device includes microperiodic gratings tilted at glancing incidence and tiled on a single substrate to provide the large field-of-view phase contrast CT system. The present disclosure is a simple, economical, and accurate method for combining multiple GAIs into a larger FOV system, capable of performing phase-contrast tomography (PC-CT) on large objects. The device and method can be applied to medical X-ray imaging, industrial non-destructive testing, and security screening.