Radiation imaging system

A radiation imaging system comprising:

• a first grating having two or more radiation shield members extending in a first direction and arranged at a first pitch in a second direction orthogonal to the first direction, radiation emitted from a radiation source passing through the first grating to generate a first periodic pattern image;
• a second grating having two or more radiation shield members extending in a first direction and arranged at a second pitch in the second direction, the radiation shield members of the second grating partly shielding the first periodic pattern image to generate a second periodic pattern image;
• a scanning section for moving at least one of the first grating and the second grating relative to the other in the second direction at a predetermined pitch;
• a radiation image detector for detecting the second periodic pattern image as an image signal;
• a processing section for imaging phase information based on the image signal obtained by the radiation image detector;
• wherein a mathematical expression DX≠n×(p1′×p2′)/|p1′−p2′| is satisfied where p1′ denotes a period of the first periodic pattern image relative to the second direction at a position of the second grating, and p2′ denotes a substantial grating pitch of the second grating relative to the second direction, and DX denotes a dimension of a radiation imaging area of each pixel in the radiation image detector relative to the second direction, and n denotes a positive integer.