MRI Research Park

Klystron Tube

William Hansen and brothers Russell and Sigurd Varian invented the klystron tube, a high-frequency amplifier for generating microwaves. It revolutionized high-energy physics and microwave research and led to the airborne radar used in aircraft today. The klystron also has been used in satellite communications, airplane and missile guidance systems, and telephone and television transmission.

Russell Varian, left, and Sigurd Varian appear in this 1951 photograph with a high-powered klystron. In the palm of his hand, Russell Varian holds a smaller type of klystron used for radar, aircraft instrument landing and microwave communications.
Photo: Stanford News Service archives

Stanford researchers in 1939 examine their invention, a klystron. Standing from left to right are Sigurd Varian, physicists David Webster and William Hansen, and in the front are Russell Varian, left, also a physicist, and John Woodyard, an engineering graduate student. Photo: Stanford News Service archives

Related Information:

The history of Stanford's physics department