William David Coolidge (; October 23, 1873 – February 3, 1975) was an American
physicist
A physicist is a scientist who specializes in the field of physics, which encompasses the interactions of matter and energy at all length and time scales in the physical universe.
Physicists generally are interested in the root or ultimate caus ...
and
engineer
Engineers, as practitioners of engineering, are professionals who invent, design, analyze, build and test machines, complex systems, structures, gadgets and materials to fulfill functional objectives and requirements while considering the l ...
, who made major contributions to
X-ray
An X-ray, or, much less commonly, X-radiation, is a penetrating form of high-energy electromagnetic radiation. Most X-rays have a wavelength ranging from 10 picometers to 10 nanometers, corresponding to frequencies in the range 30&nb ...
machines. He was the director of the
General Electric Research Laboratory
General Electric Research Laboratory was the first industrial research facility in the United States. Established in 1900, the lab was home to the early technological breakthroughs of General Electric and created a research and development environm ...
and a vice-president of the corporation. He was also famous for the development of "ductile
tungsten
Tungsten, or wolfram, is a chemical element with the symbol W and atomic number 74. Tungsten is a rare metal found naturally on Earth almost exclusively as compounds with other elements. It was identified as a new element in 1781 and first isolat ...
", which is important for the incandescent
light bulb
An electric light, lamp, or light bulb is an electrical component that produces light. It is the most common form of artificial lighting. Lamps usually have a base made of ceramic, metal, glass, or plastic, which secures the lamp in the soc ...
.
Early years
Coolidge was born on a farm near
Hudson
Hudson may refer to:
People
* Hudson (given name)
* Hudson (surname)
* Henry Hudson, English explorer
* Hudson (footballer, born 1986), Hudson Fernando Tobias de Carvalho, Brazilian football right-back
* Hudson (footballer, born 1988), Hudso ...
,
. He studied
electrical engineering
Electrical engineering is an engineering discipline concerned with the study, design, and application of equipment, devices, and systems which use electricity, electronics, and electromagnetism. It emerged as an identifiable occupation in the l ...
from 1891 until 1896 at the
Massachusetts Institute of Technology
The Massachusetts Institute of Technology (MIT) is a private land-grant research university in Cambridge, Massachusetts. Established in 1861, MIT has played a key role in the development of modern technology and science, and is one of the ...
(MIT). After a year as a laboratory assistant, he went to Germany for further study and received his doctorate from the
University of Leipzig
Leipzig University (german: Universität Leipzig), in Leipzig in Saxony, Germany, is one of the world's oldest universities and the second-oldest university (by consecutive years of existence) in Germany. The university was founded on 2 Decemb ...
. From 1899 to 1905 he was a research assistant to
Arthur A. Noyes of the Chemistry Department at MIT.
Ductile tungsten
Coolidge went to work as a researcher at
General Electric
General Electric Company (GE) is an American multinational conglomerate founded in 1892, and incorporated in New York state and headquartered in Boston. The company operated in sectors including healthcare, aviation, power, renewable energ ...
's new research laboratory in 1905, where he conducted experiments that led to the use of
tungsten
Tungsten, or wolfram, is a chemical element with the symbol W and atomic number 74. Tungsten is a rare metal found naturally on Earth almost exclusively as compounds with other elements. It was identified as a new element in 1781 and first isolat ...
as
filaments in
light bulb
An electric light, lamp, or light bulb is an electrical component that produces light. It is the most common form of artificial lighting. Lamps usually have a base made of ceramic, metal, glass, or plastic, which secures the lamp in the soc ...
s. He developed 'ductile tungsten', which could be more easily drawn into filaments, by purifying tungsten oxide. Starting in 1911, General Electric marketed lamps using the new metal and they soon became an important source of income for GE. He applied for and received a patent (US#1,082,933) for this 'invention' in 1913. However, in 1928 a US court ruled that his 1913 patent was not valid as an invention.
Improved X-ray tube
In 1913 he invented the
Coolidge tube, an X-ray tube with an improved
cathode
A cathode is the electrode from which a conventional current leaves a polarized electrical device. This definition can be recalled by using the mnemonic ''CCD'' for ''Cathode Current Departs''. A conventional current describes the direction in whi ...
for use in
X-ray
An X-ray, or, much less commonly, X-radiation, is a penetrating form of high-energy electromagnetic radiation. Most X-rays have a wavelength ranging from 10 picometers to 10 nanometers, corresponding to frequencies in the range 30&nb ...
machines that allowed for more intense visualization of deep-seated anatomy and
tumors
A neoplasm () is a type of abnormal and excessive growth of tissue. The process that occurs to form or produce a neoplasm is called neoplasia. The growth of a neoplasm is uncoordinated with that of the normal surrounding tissue, and persists ...
. The Coolidge tube, which also utilized a
tungsten
Tungsten, or wolfram, is a chemical element with the symbol W and atomic number 74. Tungsten is a rare metal found naturally on Earth almost exclusively as compounds with other elements. It was identified as a new element in 1781 and first isolat ...
filament, was a major development in the then-nascent medical specialty of
radiology
Radiology ( ) is the medical discipline that uses medical imaging to diagnose diseases and guide their treatment, within the bodies of humans and other animals. It began with radiography (which is why its name has a root referring to radiat ...
(US patent filed in 1913 and granted as US Patent 1,203,495 in 1916). Its basic design is still in use. He also invented the first rotating anode X-ray tube.
Awards
The
American Academy of Arts and Sciences
The American Academy of Arts and Sciences (abbreviation: AAA&S) is one of the oldest learned societies in the United States. It was founded in 1780 during the American Revolution by John Adams, John Hancock, James Bowdoin, Andrew Oliver, and ...
awarded Coolidge the
Rumford Prize
Founded in 1796, the Rumford Prize, awarded by the American Academy of Arts and Sciences, is one of the oldest scientific prizes in the United States. The prize recognizes contributions by scientists to the fields of heat and light. These terms ...
in 1914. Coolidge was awarded the
American Institute of Electrical Engineers
The American Institute of Electrical Engineers (AIEE) was a United States-based organization of electrical engineers that existed from 1884 through 1962. On January 1, 1963, it merged with the Institute of Radio Engineers (IRE) to form the Instit ...
Edison Medal
The IEEE Edison Medal is presented by the Institute of Electrical and Electronics Engineers (IEEE) "for a career of meritorious achievement in electrical science, electrical engineering, or the electrical arts." It is the oldest medal in this f ...
in 1927 ''For his contributions to the incandescent electric lighting and the X-rays art''. He rejected this prestigious award in 1926 on the basis that his ductile tungsten patent (1913) was ruled by court as invalid. He was awarded the
Howard N. Potts Medal
The Howard N. Potts Medal was one of The Franklin Institute Awards for science and engineering award presented by the Franklin Institute of Philadelphia, Pennsylvania. It is named for Howard N. Potts. The first Howard N. Potts Medal was awarded in ...
in 1926 and the
Louis E. Levy Medal
The Franklin Institute is a science museum and the center of science education and research in Philadelphia, Pennsylvania. It is named after the American scientist and wikt:statesman, statesman Benjamin Franklin. It houses the Benjamin Franklin ...
in 1927. Coolidge was awarded the
Faraday Medal
The Faraday Medal is a top international medal awarded by the UK Institution of Engineering and Technology (IET) (previously called the Institution of Electrical Engineers (IEE)). It is part of the IET Achievement Medals collection of awards. T ...
in 1939. He was awarded the
Franklin Medal
The Franklin Medal was a science award presented from 1915 until 1997 by the Franklin Institute located in Philadelphia, Pennsylvania, U.S. It was founded in 1914 by Samuel Insull
Samuel Insull (November 11, 1859 – July 16, 1938) was a Bri ...
in 1944.
[James E. Brittain ''History William D. Coolidge and Ductile Tungsten'' in ''IEEE Industry Applications Magazine'', Sept/Oct 2004, page 10] The city of Remscheid awarded him with the
Röntgen Medal for his invention of the hot cathode X-ray tube in 1963. In 1975 he was elected to the
National Inventors Hall of Fame
The National Inventors Hall of Fame (NIHF) is an American not-for-profit organization, founded in 1973, which recognizes individual engineers and inventors who hold a U.S. patent of significant technology. Besides the Hall of Fame, it also opera ...
, shortly before his death at age 101 in
Schenectady
Schenectady () is a city in Schenectady County, New York, United States, of which it is the county seat. As of the 2020 census, the city's population of 67,047 made it the state's ninth-largest city by population. The city is in eastern New Y ...
, New York.
Later career
Coolidge became director of the GE research laboratory in 1932, and a vice-president of General Electric in 1940, until his retirement in 1944. He continued to consult for GE after retirement.
Patents
* Coolidge, , "Tungsten and method of making the same for use as filaments of incandescent electric lamps and for other purposes."
* Coolidge, , Coolidge tube
* Coolidge, , "''
X-ray tube
An X-ray tube is a vacuum tube that converts electrical input power into X-rays. The availability of this controllable source of X-rays created the field of radiography, the imaging of partly opaque objects with penetrating radiation. In contrast ...
''"
* Coolidge, , "''X-ray apparatus''"
* Coolidge, , "''
Stereoscopic
Stereoscopy (also called stereoscopics, or stereo imaging) is a technique for creating or enhancing the depth perception, illusion of depth in an image by means of stereopsis for binocular vision. The word ''stereoscopy'' derives . Any stere ...
x-ray apparatus''"
* Coolidge, , "''X-ray apparatus''"
* Coolidge, , "''X-ray apparatus''"
* Coolidge, , "''X-ray apparatus''"
* Coolidge, , "''X-ray apparatus''"
* Coolidge, , "''X-ray apparatus''"
* Coolidge, , "''X-ray tube shield
* Coolidge, , "''X-ray device''"
* Coolidge, , "''X-ray apparatus''"
* Coolidge, , "''X-ray apparatus''"
* Coolidge, , "''X-ray apparatus''"
* Coolidge, , "''X-ray apparatus and method''"
* Coolidge, , "''X-ray apparatus''"
* Coolidge, , "''X-ray apparatus''"
* Coolidge, , "''X-ray apparatus''"
* Coolidge, , "''X-ray device''"
* Coolidge, , "''X-ray
anode
An anode is an electrode of a polarized electrical device through which conventional current enters the device. This contrasts with a cathode, an electrode of the device through which conventional current leaves the device. A common mnemonic is ...
''"
* Coolidge, , "''X-ray tube''"
* Coolidge, , "''X-ray tube''"
* Coolidge, , "''X-ray device''"
* Coolidge, , "''X-ray device''"
Notes
References
**
*
External links
The Cathode Ray Tube siteWilliam Coolidge's Case File at The Franklin Institutewith info about his 1926 Franklin Award for the x-ray tube
IEEE History Center biographyNational Academy of Sciences Biographical MemoirAndrea Sella's Classic Kit: Coolidge's X-ray Tube*John Anderson Miller, ''Yankee scientist: William David Coolidge'', Mohawk Development Service, 1963
{{DEFAULTSORT:Coolidge, William
American physicists
Members of the United States National Academy of Sciences
IEEE Edison Medal recipients
MIT School of Engineering alumni
20th-century American inventors
American centenarians
Men centenarians
People from Hudson, Massachusetts
1873 births
1975 deaths
Howard N. Potts Medal recipients