(eV) Electron volt is an energy unit defined as 1.60919 x10^-19 joules (in older unit 1.60919 x10^-12 erg). One electron volt is equal to the kinetic energy required to raise an electron through a potential difference of one volt (in a vacuum). The electron volt is not an SI unit but its use is valid within the International System for atomic (eV), electronic (keV), nuclear (MeV), and subnuclear processes (GeV or TeV).

In medical imaging used units:
MeV: One million electron volts
keV: One thousand electron volts.

An element consists of atoms having the same structure and the same chemically reaction.

A film consists of a thin, transparent sheet of polyester or similar material. Films are coated on one or both sides with an emulsion sensitive to radiation, light or heat. Films are relatively radiolucent due to their relatively low atomic number (that of silver halide).

See also X-Ray Film, Direct Exposure Film and Intensifying Screen.

Atomic or nuclear fission is the process of splitting a heavy nucleus into two lighter nuclei. Some nuclides split up spontaneous as a type of radioactive decay. In other elements, fission is induced through the reaction of an incident radiation with the nucleus. High energy rates are released during the fission reaction (difference between the binding energies); this energy is used to produce heat and electricity e.g. in nuclear power plants.

A fluoroscope projects x-ray images in a video sequence (movie) onto a screen monitor.
Early generation fluoroscopes presented particularly difficult viewing challenges for radiologists. The human retina contains two types of image receptors. Cones (central vision) operate better in bright light, while rods (peripheral vision) are more sensitive to blue-green light and low light. Therefore, the radiologists wear red goggles to filter out blue-green wavelengths to allow the rods to recover peak sensitivity before viewing fluoroscopic images.
To avoid this time consuming accommodation, the industry developed the image intensifier tube in the 1950s. Due to the high amount of individual images during a fluoroscan, a very sensitive amplifier is needed to cut down radiation exposure. Until today, image intensifiers amplify the faint light emitted by the fluorescing screen and the images can be viewed on a monitor. Recently, digital technique replaces the large and bulky image intensifier with flat-panel technology.
Various other components of a fluoroscope system include a gantry, patient table, x-ray tube, filters, collimators, images sensor, camera and computer, most similar to other radiographic systems.
A fluoroscopy system provides the view of moving anatomic structures and is valuable in performing procedures that require continuous imaging and monitoring, such as barium studies, gastrointestinal function tests, cardiac functions, studies of diaphragmatic movement, or catheter placements. A number of technologies are available to record images created during fluoroscopic (fluorographic) exams.