Electronics based innovation in a niche market distances measured by the speed of light /

by 1950- Murphy, James Smith

MURPHY, JAMES SMITH. Electronics Based Innovation In A Niche Market: Distances Measured By The Speed Of Light (Under the direction of Dr. Ross Bassett) The purpose of this study is to document the development of an accurate, affordable, reliable machine to perform the relatively long distance measurements routinely made by land surveyors. Prior to the development of the technology, surveyors used a variety of contact instruments for measurement: ropes, rods, poles, chains and steel tapes. The difficulty of obtaining results on long measurements by contact devices led innovators of the Eighteenth and Nineteenth centuries to develop alternate noncontact methods of measuring: subtense bar, stadia wires and triangulation, all of which came with their own inadequacies. In 1951, Erik Bergstrand, a physicist with the Swedish Geographical Survey Office culminated thirteen years of research by bringing an electronic distance meter which measured distances based on the speed of light to the market. Research efforts undertaken during and after World War II in applied electronics and wave propagation led to the maser, which allowed South Africans Harry Baumann and T. L. Wadley to develop and market a device using the microwave spectrum to measure. Maser research was the progenitor of the laser, which led to the discovery of the lasing properties of a Gallium Arsenide diode emitting light in the infrared spectrum. Advances in transistors and integrated circuit technology introduced the simplification and miniaturization to electronic distance measuring that would transform the once novel instrument into a commodity product. This thesis explores that transition primarily through the words of those who used these instruments on a daily basis, from the pioneers in the geodetic community who measured between mountain peaks down to the practicing land surveyor who made his living surveying farms and marking out lots in new subdivisions.