William D. Coolidge

Infobox Scientist
name = William D. Coolidge


caption = William Coolidge, Willis Rodney Whitney, Thomas Edison, Charles Proteus Steinmitz, Irving Langmuir
birth_date = October 23, 1873
birth_place = Hudson, Massachusetts
death_date = death date and age|1975|2|3|1873|10|23
death_place = Schenectady, New York
residence = United States
citizenship =
nationality = American
ethnicity =
fields = Electrical engineering
workplaces =
alma_mater = University of Leipzig Massachusetts Institute of Technology
doctoral_advisor =
academic_advisors =
doctoral_students =
notable_students =
known_for = his contributions to the incandescent electric lighting and the X-rays art
influences =
influenced =
awards = IEEE Edison Medal


footnotes =

William David Coolidge (October 23, 1873 – February 3, 1975) [cite web|last = Suits|first = C. G.|title = National Academy of Sciences Memorial Biography|publisher = National Academy of Sciences|url = http://www.harvardsquarelibrary.org/unitarians/coolidge.html|accessdate = 2008-05-09] was an American physicist, who made major contributions to X-ray machines. He was the director of the General Electric Research Laboratory and a vice-president of the corporation. He was also famous for the invention of "ductile tungsten", which is important for the incandescent light bulb.

Coolidge was born in Hudson, Massachusetts. He studied electrical engineering from 1891 until 1896 at the Massachusetts Institute of Technology (MIT). He went to Germany for further study and received his doctorate from the University of Leipzig. From 1899 to 1905 he was a research assistant to Arthur A. Noyes of the Chemistry Department at MIT.

Coolidge went to work as a researcher at General Electric new research laboratory in 1905, where he conducted critical experiments that led to the use of tungsten as filaments in light bulbs. (Note: He got a patent on this in 1913. However, later it was ruled by court that his 1913 patent was not valid as an invention. Please read the reference by J.E. Brittain, 2004.) In 1913 he invented the Coolidge tube, an X-ray tube with an improved cathode for use in X-ray machines that allowed for more intense visualization of deep-seated anatomy and tumors. The Coolidge tube, which also utilized a tungsten filament, was a major development in the then-nascent medical specialty of radiology, and its basic design is still in use. He filed for patent in 1913 and finally it was granted as US Patent 1,203,495 in 1916.

Coolidge was awarded the American Institute of Electrical Engineers Edison Medal 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. In 1975 he was elected to the National Inventors Hall of Fame, shortly before his death at age 101 in Schenectady, New York.

Patents

* Coolidge, US patent|1,203,495, Coolidge tube
* Coolidge, US patent|1211092, "X-ray tube"
* Coolidge, US patent|1215116, "X-ray apparatus"
* Coolidge, US patent|1250093, "Stereoscopic x-ray apparatus"
* Coolidge, US patent|1310061, "X-ray apparatus"
* Coolidge, US patent|1365638, "X-ray apparatus"
* Coolidge, US patent|1394143, "X-ray apparatus"
* Coolidge, US patent|1409989, "X-ray apparatus"
* Coolidge, US patent|1430550, "X-ray apparatus"
* Coolidge, US patent|1437290, "X-ray tube shield"
* Coolidge, US patent|1502907, "X-ray device"
* Coolidge, US patent|1529344, "X-ray apparatus"
* Coolidge, US patent|1541627, "X-ray apparatus"
* Coolidge, US patent|1543654, "X-ray apparatus"
* Coolidge, US patent|1550506, "X-ray apparatus and method"
* Coolidge, US patent|1550507, "X-ray apparatus"
* Coolidge, US patent|1600867, "X-ray apparatus"
* Coolidge, US patent|1655455, "X-ray apparatus"
* Coolidge, US patent|1659133, "X-ray device"
* Coolidge, US patent|1714975, "X-ray anode"
* Coolidge, US patent|1917099, "X-ray tube"
* Coolidge, US patent|1946312, "X-ray tube"
* Coolidge, US patent|1967869, "X-ray device"
* Coolidge, US patent|1971812, "X-ray device"

References

*M.F. Wolff, "William D. Coolidge: shirt-sleeves manager", IEEE Spectrum, vol. 21, no. 5 (May 1984), pp. 81-85.
*J.E. Brittain, "William D. Coolidge and ductile tungsten", IEEE Industry Applications Magazine, vol. 10, no. 5 (September/October 2004), pp. 9-10.
*J.E. Brittain, "Electrical Engineering Hall of Fame: William D. Coolidge", Proc. IEEE, vol. 94, no. 11 (November 2006), pp. 2045-2048.

External links

* [http://members.chello.nl/~h.dijkstra19/page5.html The Cathode Ray Tube site]
* [http://fi.edu/case_files/coolidge_2853/ William Coolidge's Case File at The Franklin Institute] with info about his 1926 Franklin Award for the x-ray tube
* [http://www.ieee.org/web/aboutus/history_center/biography/coolidge.html IEEE History Site Wiiliam D. Coolidge]