Abstract: A memory includes: a magnet including a first and second portions adjacent in a first direction. The first portion has a first dimension in a second direction at a first position at which a dimension of the magnet in the second direction is maximum, the second direction perpendicular to the first direction, the second portion has a second dimension in the second direction at a second position at which a dimension of the magnet in the second direction is minimum, the second dimension smaller than the first dimension, the first portion is continuous to the second portion via a third position between the first and second positions, a curve corresponding to an outer of the magnet extends between the first and third positions, and the curve passes through a side closer to the central axis of the magnet than a straight line connecting the first and second positions.

Abstract: A strain detector which is improved in corrosion resistance and moisture resistance and is high in reliability. The strain detector comprises a driven member, a magnetic shielding layer of a non-magnetic or diamagnetic material selectively formed on the driven member, a magnetic layer formed at a portion of the driven member at which the magnetic shielding layer is not formed, and a detecting coil provided corresponding to the magnetic layer. The magnetic layer may be formed in such a manner as to project from the driven member by selectively removing a surface of the driven member. Preferably, a protecting layer is formed on surfaces of the magnetic layer and the magnetic shielding layer. A process of producing such strain detector is also disclosed by which a magnetic shielding layer can be formed only at a required portion of a driven member readily in a short period of time.