William David Coolidge (/ˈkuːlɪdʒ/; October 23, 1873 – February 3, 1975)[1] was an American physicist and engineer, who made major contributions to X-ray machines.

Starting in 1911, General Electric marketed lamps using the new metal and they soon became an important source of income for GE.

He rejected this prestigious award in 1926 on the basis that his ductile tungsten patent (1913) was ruled by court as invalid.

[8] 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, shortly before his death at age 101 in Schenectady, New York.