US Patent 8698094 Permanent magnet lens array

A permanent magnetic lens array for charged-particle focusing includes a first sheet of soft magnetic material, wherein the first sheet of soft magnetic material includes a plurality of snorkel cone protrusions arranged in an array pattern, wherein each snorkel cone is axially symmetric and includes an opening passing from a first surface of the first sheet of soft magnetic material to a second surface of soft magnetic material, and a plurality of permanent magnetic elements, wherein each permanent magnetic element is axially symmetric and arranged concentrically with a snorkel cone of the first sheet of soft magnetic material, wherein the snorkel cones of the first sheet of soft magnetic material and the plurality of permanent magnetic elements are configured to form a plurality of magnetic lenses, wherein each magnetic lens has a magnetic field with an axial component oriented perpendicular to the first surface of the soft magnetic material.