초록 |
An evaluation aid serves as a phantom (imitation lesion) when a digital X-ray image is taken, and evaluation is then carried out through the digital X-ray image. The evaluation aid can simplify evaluating image qualities of a digital X-ray image for X-ray absorption parts having different X-ray absorption ratios all at once. The evaluation aid contains a substrate (plate-like body) including a plurality of regions having different X-ray absorption ratios for taking a digital X-ray image to carry out evaluation. Step members are provided on the plate-like body so as to correspond to the plurality of regions, respectively, where each step member includes a plurality of subregions having different X-ray absorption ratios. Preferably the thicknesses and/or constituent materials of the plurality of regions of the substrate are different from each other in order to have different X-ray absorption ratios in these regions. |