Coolidge tube, United States, 1920
American physicist William Coolidge (1832-1919) patented his ‘hot cathode’ tube in 1913. The cathode was a heated, electron-emitting tungsten filament. It produced a high output of X-rays that did not fluctuate and were easily adjusted. This eliminated many problems of the older so-called ‘gas tubes’. Combined with more reliable power supplies, it allowed X-ray techniques to become standardised and reproducible. The fins at the end of the tube disperse the heat generated in the tungsten anode which the larger currents use.
Object number:
A600223
Related Themes and Topics
Glossary:
Glossary: radiology
The scientific study of X-rays and other high energy radiation, especially as used in medicine.
Glossary: x-ray tube
The part of an X-ray machine that produces X-rays. The tube itself operates under vacuum conditions.
Glossary: x-rays
A wave of electromagnetic radiation that has high energy and short wavelength. It is able to pass through many materials, except those of high density such as metals or bones. Discovered in 1895 by William Roentgen.