X-ray phase difference imaging system and phase contrast image correction method

An X-ray phase difference imaging system comprising:

• an X-ray source;
• a plurality of gratings that include a first grating irradiated with an X-ray from the X-ray source, and a second grating irradiated with the X-ray from the first grating;
• a detector that detects the X-ray irradiated from the X-ray source;
• and
• an image processor that generates a phase contrast image by using an X-ray image detected by the detector,
• wherein the image processor is configured to
• acquire a first X-ray image captured in a state in which a subject is not disposed,
• acquire a second X-ray image captured in a state in which the subject is not disposed and a third X-ray image captured in a state in which the subject is disposed after the first X-ray image is acquired,
• reconstruct a first phase contrast image by using the first X-ray image and the second X-ray image,
• reconstruct a second phase contrast image by using the first X-ray image and the third X-ray image, and
• correct an artifact of the second phase contrast image on the basis of the first phase contrast image.

A phase contrast image correction method comprising:

• capturing a first X-ray image in a state in which a subject is not disposed;
• capturing a second X-ray image in a state in which the subject is not disposed;
• capturing a third X-ray image in a state in which the subject is disposed before or after the second X-ray image is captured;
• reconstructing a first phase contrast image by using the first X-ray image and the second X-ray image that are captured such that a time interval between capturing of the second X-ray image and capturing of the third X-ray image is shorter than a time interval between capturing of the first X-ray image and capturing of the third X-ray image;
• reconstructing a second phase contrast image by using the first X-ray image and the third X-ray image;
• and
• correcting an artifact of the second phase contrast image on the basis of the first phase contrast image.