Astronomers in the 17th century understood that a beam of light could be used
to measure the distance from one point to another, but it was the rapid
development of electronics during and after World War II that made the practical
implantation of this idea possible. The Geodimeter, the first EDM using visible
light, was produced in Sweden in 1953. The Tellurometer, the first EDM using
microwave radiation, was produced in South Africa in 1954. Infrared EDMs became
available in the late 1960s. EDMs were substantially more expensive than chains
and tapes, but also substantially more precise, and they quickly displaced these
traditional distance measuring instruments.
Ref: Ronald Cox, "Distance-Measurement, Electromagnetic," pp. 177–180
in Robert Bud and Deborah Warner, eds., Instruments of Science (New York
and London, 1998).
