 Not until 1961 did he complete a working prototype of his idea, apply (for $1700) for a patent on his idea, and publish an article detailing the work.Ingeniously, by using materials found in his home (such as his son's toy train, a phonograph turntable, and an alarm clock motor), Oldendorf demonstrated a method of producing cross-sectional images of soft tissue by back-projection and reconstruction.In his landmark paper, also published in 1961, he described the basic concept later used by Allan McLeod Cormack to develop the mathematics behind computerized tomography, though Prof. Cormack was unaware of Oldendorf's work.