radiography

Branch of science concerned with the use of radiation (particularly X-rays) to produce images on photographic film or fluorescent screens. X-rays penetrate matter according to its nature, density, and thickness. In doing so they can cast shadows on photographic film, producing a radiograph. Radiography is widely used in medicine for examining bones and tissues and in industry for examining solid materials; for example, to check welded seams in pipelines. The field has been transformed by the technique of computed tomography, in which X-ray images produced in numerous scans are combined by computer to form a false-colour image of the three-dimensional structure of internal organs.