PROBLEM TO BE SOLVED: To improve the image quality of a tomographic image while shortening the calculation time in a tomographic image generating device, method and program for generating the tomographic image from a plurality of projection images acquired by performing imaging at a plurality of radiation source positions like tomosynthesis imaging.SOLUTION: An image acquisition part 31 acquires a plurality of projection images by imaging a subject M at each of a plurality of radiation source positions. A pixel value projection part 32 projects the pixel values of the plurality of projection images to the coordinate position on the desired tomographic plane of the subject M on the basis of the positional relation between the radiation source position and a radiation detector at the time of imaging for each of the plurality of projection images while holding the pixel values of the plurality of projection images. A pixel value calculation part 33 generates a tomographic image of the tomographic plane by calculating the pixel value at the attention coordinate position on the basis of the plurality of pixel values of the projection images projected within a predetermined range with the attention coordinate position on the tomographic plane as the reference.SELECTED DRAWING: Figure 3
