| 摘要 |
A variable delay device for delaying an electrical signal includes a bar-shaped magnetostrictive member to be a transmitting path of a supersonic wave, an input transducer for converting an electric signal into a supersonic wave and an output transducer for converting a supersonic wave into an electric signal, the input and output transducers being provided at at opposite end portions of the magnetostrictive member, and a magnetic field producing device provided between the input and output transducers for supplying the magnetostrictive member with a magnetic field which varies in intensity along the elongated direction of the magnetostrictive member. The magnetic field supplied to the magnetostrictive member is controlled by a control signal applied to the magnetic field producing device to vary the Young's modulus of the magnetostrictive member. As a result, the velocity of the supersonic wave being transmitted therein is varied, to thereby control the delay time of the electric signal. |
