logic circuit
A logic gate is an idealized or physical device implementing a Boolean function, a logical operation performed on one or more binary inputs that produces a single binary output. Depending on the context, the term may refer to an ideal logic gat ...
element invented by Eiichi Goto in 1954.Information Processing Society of Japan Parametron /ref> The parametron is essentially a resonant circuit with a nonlinear reactive element which oscillates at half the driving frequency. The oscillation can be made to represent a binary digit by the choice between two stationary phases π radians (180 degrees) apart.U.S. Patent and Trademark Office Class 307, Electrical Transmission or Interconnection Systems - Subclass 402, Parametrons /ref>
Parametrons were used in early Japanese computers from 1954 through the early 1960s. A prototype parametron-based computer, the PC-1, was built at the
University of Tokyo
, abbreviated as or UTokyo, is a public research university located in Bunkyō, Tokyo, Japan. Established in 1877, the university was the first Imperial University and is currently a Top Type university of the Top Global University Project b ...
in 1958. Parametrons were used in early Japanese computers due to being reliable and inexpensive but were ultimately surpassed by
transistor
upright=1.4, gate (G), body (B), source (S) and drain (D) terminals. The gate is separated from the body by an insulating layer (pink).
A transistor is a semiconductor device used to Electronic amplifier, amplify or electronic switch, switch ...
Parametric oscillator
A parametric oscillator is a driven harmonic oscillator in which the oscillations are driven by varying some parameter of the system at some frequency, typically different from the natural frequency of the oscillator. A simple example of a param ...