US Patent 7219552 Scalable high sensitivity magnetostrictive pressure sensor

A pressure sensor 10 includes a casing 12 configured to be able to be filled with a fluid 16 such as a liquid or a gas, in which at least part of a surface contacting this fluid 16 is formed of a giant magnetostrictive member 18 made of a giant magnetostrictive element, and detecting means for detecting a change in magnetic permeability or an amount of remanent magnetization attributable to expansion and contraction of the giant magnetostrictive member 18 based on a pressure change of the fluid 16 filled in this casing 12. The pressure sensor 10 can detect pressure at high sensitivity and high accuracy in a short time while achieving miniaturization of a device at the same time.