Phillip Hagar Smith (April 29, 1905 in

Lexington, Massachusetts Lexington is a suburban town in Middlesex County, Massachusetts, United States. It is 10 miles (16 km) from Downtown Boston. The population was 34,454 as of the 2020 census. The area was originally inhabited by Native Americans, and was firs ...

– August 29, 1987 in

Berkeley Heights, New Jersey Berkeley Heights is a township in Union County, New Jersey, United States. A commuter town in northern- central New Jersey, the township is nestled within the Raritan Valley region in the New York metropolitan area. As of the 2010 United State ...

) was an

electrical engineer 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 ...

, who became famous for his invention of the

Smith chart The Smith chart, invented by Phillip H. Smith (1905–1987) and independently by Mizuhashi Tosaku, is a graphical calculator or nomogram designed for electrical and electronics engineers specializing in radio frequency (RF) engineering to assis ...

. Smith graduated from

Tufts College Tufts University is a private research university on the border of Medford and Somerville, Massachusetts. It was founded in 1852 as Tufts College by Christian universalists who sought to provide a nonsectarian institution of higher learning. ...

in 1928 with a BS degree in electrical engineering. While working for

Bell Telephone Laboratories Nokia Bell Labs, originally named Bell Telephone Laboratories (1925–1984), then AT&T Bell Laboratories (1984–1996) and Bell Labs Innovations (1996–2007), is an American industrial research and scientific development company owned by mul ...

, he invented his eponymous Smith chart (which was also invented independently in 1937 by Mizuhashi Tosaku). When asked why he invented the chart, Smith explained, "From the time I could operate a

slide rule The slide rule is a mechanical analog computer which is used primarily for multiplication and division, and for functions such as exponents, roots, logarithms, and trigonometry. It is not typically designed for addition or subtraction, which is ...

, I've been interested in graphical representations of mathematical relationships." In 1969 he published the book ''Electronic Applications of the Smith Chart: In Waveguide, Circuit, and Component Analysis'', a comprehensive work on the subject. He retired from Bell Labs in 1970. He was elected a fellow of the

IRE Ire or IRE may refer to: Ire * Extreme anger; intense fury * Irē, the Livonian name for Mazirbe, Latvia * A town in Oye, Nigeria * ''Ire'' (album), a 2015 album by the Australian metalcore band Parkway Drive * Ire (Iliad), a town mentioned in ...

in 1952. Although best known for his Smith Chart, he made important contributions in a variety of fields, including radar, FM, and antennas (including use of the Luneburg lens). The IEEE History Center conducted an interview with Smith in 1973, the edited transcript and audio clips from which are on the web.

Notes

External links

Philip H. Smith, an oral history conducted in 1973 by Frank A. Polkinghorn, IEEE History Center
* 1905 births 1987 deaths Scientists at Bell Labs Tufts University School of Engineering alumni 20th-century American engineers {{US-engineer-stub