1. A digital x-ray tomosynthesis system comprising: A) at least one x-ray source, B) a two-dimensional digital x-ray image sensor, C) an x-ray data collection-positioning mechanism for positioning, relative to each other, said at least one x-ray source, said image sensor and an object for collecting with said image sensor x-ray attenuation data representing attenuation of a large number of rays of x-radiation from said at least one source through said object to said image sensor, and D) a computer processor programmed with an algorithm for producing tomographic or three-dimensional images of said object or portions of said object using a least squares technique with functional generalization.