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William Coolidge: Vacuum Tube for X-Ray Production, 1926


At the age of 100, William David Coolidge was admitted to the Inventors Hall of Fame. Earlier in his life, he was the recipient of many medals and honors including the 1926 Edison Medal of the American Institute of Electrical Engineers and the Rumford Prize of the American Academy of Sciences, in addition to the 1926 Howard N. Potts medal described here.

Eighty-three patents were granted to William Coolidge, the most significant being Patent No. 1,082,933 for the method of making tungsten filament for use in the incandescent electric lamp and other purposes (such as X-ray tubes) and Patent No. 1,203,495 for the vacuum tube used in his X-ray generator. His patent concerning ductile tungsten was later invalidated on the basis that the ductile nature of tungsten was an inherent characteristic of the element and so Coolidge chose to refuse the 1926 Edison Prize with the citation "for the origination of ductile tungsten and the fundamental improvement of the X-ray tube." Instead, he received the 1927 Edison Medal for "contributions to the incandescent electric lighting and the X-rays art."

CSA Report

Report of the Sub-Committee
on Science and the Arts,
Report on the Investigation of the
Coolidge Tube invented
by William D. Coolidge.
Signed. 5/5/1926. (397K)
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X-Ray Tube Report

Report from the Committee Secretary,
Describing the structure and
operation of the Coolidge Tube (359K)
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