On 8 November 1895, Willhelm Röntgen, a physicist working at the University of Wurzburg discovered X rays when a photographic plate shut in a draw was found to be exposed when left close to a sample of uranium salt. Röntgen's work provided him with the distinction of being the first recipient of the Nobel Prize for Physics in 1901.
X-rays are able to penetrate through many materials. This property makes it possible to use X-ray equipment to create an image of the inside of the human body without the need for an invasive procedure. The process involves creating a concentrated beam of electrons and pointing them into a metal film. The result of that crash between the metallic film and the highly charged electrons is a concentration of high-energy electromagnetic radiation. This radiation is what is normally termed X-rays.
Along with the sheet of metallic film, a second sheet serves as a filter that prevents the beam from scattering or making the image produced by the action foggy or otherwise difficult to view. As the image appears, the portions of the body that contain certain elements, such as calcium enriched bones, will appear outlined. Other mineral deposits help to identify the presence of growths such as tumours, and other irregularities can be seen, such as breaks in the bones or foreign objects in the body, like knife blades or bullets. In some instances, the patient may ingest what is known as a contrast agent, such as barium or iodine. This helps to make the presence of blood vessels and organs appear more prominently on the X-ray.
X-ray technology is not without some degree of risks. High levels of exposure to radiation in a short period of time can produce a variety of health problems. Still, the occasional exposure to X-rays during an annual checkup or at the dentist's office are not likely to result in any type of permanent damage. X-rays are not recommended for pregnant women in most cases, however.
X-rays are not just used for imaging the human body for medical purposes. The same basic process is used to scan baggage at many airports, check suspicious packages at a post office or courier depot, and to scan the interior of walls to check for electrical lines and pipes before demolition of the wall.
