Dual coil, translational bias-field device for a magneto-optical system

Abstract

A translational, bias-field device for a magneto-optical system having a magneto-optical recording element moving through a first magnetic field created by the bias-field device so that information is selectively recorded on or erased from the recording element, the device comprises a housing and a first rail for enabling translational movement attached to said housing. A permanent magnet structure is polarized through its cross-section having a first set of north and south poles on a first surface positioned adjacent the magneto-optic recording element for providing the first magnetic field to the recording element, and a second set of north and south poles on a second surface, and the permanent magnet structure attached to the first rail which enables translational movement of the magnet structure. A first coil is positioned adjacent to the magnet which, when energized, imparts a second magnetic field to the permanent magnet structure for imparting motion to the permanent magnet structure, and a second coil is positioned adjacent to the magnet which, when energized, imparts a third magnetic field to the permanent magnet structure for also imparting motion to the permanent magnet structure.