Patent ID: 7346204

Claim:
A method of generating a phase contrast image on the basis of a plurality of radiation images of an object taken in imaging positions which are different from each other in the distance from the object, wherein an improvement comprises that at least one of an enlargement and reduction processing is carried out on the radiation images as taken in the imaging positions according to the distances between the imaging positions so that the radiation images become substantially the same in their sizes, and a phase contrast image is generated on the basis of the radiation images thus processed, wherein the phase contrast image represents a phase shift amount according to the plurality of radiation images, and the phase contrast image is generated by performing spatial frequency conversion on each of the plurality of radiation images on which the at least one of the enlargement and the reduction processing has been performed, by obtaining a phase shift amount by calculation using a spatial frequency component of each of the plurality of radiation images, on which the spatial frequency conversion has been performed, and by generating an image based on the obtained phase shift amount.