Spatial localisation of NMR signals and electrical scanning of sensitive regions by the magnetic focusing method.

The spatial localisation of NMR signals by the magnetic focusing method is examined and a method for electrical scanning of a spatially localised region is proposed. The small amount of signal from points of the star taper in static field focusing can almost be neglected, and the spatial localisation of the signal corresponds to the shape of a prolate spheroid in the centre region of the star-shaped focusing field. Electrical scanning of the focused region can be achieved at any position in the magnet system by superimposing linear field gradients on the focused field in the scanning direction. These are the inherent limitations of the static magnetic field focusing method. The embodiment of the scanning movement of the focused field is also confirmed.