When the electrons collide with the target, about 1% of the resulting energy is emitted as X-rays, with the remaining 99% released as heat.
Due to the high energy of the electrons that reach relativistic speeds, the target is usually made of tungsten even if other material can be used particularly in XRF applications.
A fully functioning unit was introduced to the public at the 1904 World's Fair by Clarence Dally.
[3] The technology developed quickly: In 1909 Mónico Sánchez Moreno had produced the first portable medical device and during World War I Marie Curie led the development of X-ray machines mounted in "radiological cars" to provide mobile X-ray services for military field hospitals.
Van de Graaff, John G. Trump developed one of the first million-volt X-ray generators.
X-ray machines are used in health care for visualising bone structures, during surgeries (especially orthopedic) to assist surgeons in reattaching broken bones with screws or structural plates, assisting cardiologists in locating blocked arteries and guiding stent placements or performing angioplasties and for other dense tissues such as tumours.
Some forms of radiography include: In fluoroscopy, imaging of the digestive tract is done with the help of a radiocontrast agent such as barium sulfate, which is opaque to X-rays.
Radiotherapy — the use of x-ray radiation to treat malignant and benign cancer cells, a non-imaging application Fluoroscopy is used in cases where real-time visualization is necessary (and is most commonly encountered in everyday life at airport security).
Luggage at airports and student baggage at some schools are examined for possible weapons, including bombs.
A film of carbon nanotubes (as a cathode) that emits electrons at room temperature when exposed to an electrical field has been fashioned into an X-ray device.
[6] Engineers at the University of Missouri (MU), Columbia, have invented a compact source of x-rays and other forms of radiation.
The radiation source is the size of a stick of gum and could be used to create portable x-ray scanners.