1. An image display device that displays a plurality of radiological images including the same photographic subject for comparison, comprising: a correction amount calculation unit for calculating a correction amount for matching the position and/or image quality of radiological images other than a reference radiological image among the plurality of radiological images with the position and/or image quality of the reference radiological image for each of the other radiological images; and a storage processing unit for storing the correction amount for each of the other radiological images so as to be associated with the reference radiological image.