ABSTRACT
A comprehensive treatment of the physics, history, technology, reliability, and commercial aspects of diagnostic X-ray sources can be found. The center line of the invisible X-ray focal spot where electrons impact the target and the center line of the visible glowing rectangular area are oriented in parallel, but askew by about half a focal spot width. The X-ray focal spot, where the X-rays emerge, is slightly wider than the white glowing hot zone where thermal radiation emerges with relatively high intensity. The chapter explains the working principle of an entire X-ray tube with a sample glass X-ray tube. The X-ray focal spot is kept at a fixed position relative to the tube housing by a stationary magnetic dipole field. According to Food and Drug Administration terminology, an X-ray source assembly is comprised of a tube and tube housing, which both make up the tube housing assembly, and a beam limiting device.
