Reflectrons and methods of producing and using them

A reflectron comprising:

• a plurality of lenses, in which at least a first lens comprises a first planar body comprising a first surface and a second surface, the first planar body comprising an aperture between a first side and a second side of the first surface of the first planar body, the first planar body further comprising a plurality of separate and individual conductors spanning the aperture from the first side to the second side of the first surface of the first planar body, each of the plurality of conductors attached to the first surface of the first planar body at the first side and at the second side of the first surface, in which the plurality of individual conductors are each substantially parallel to each other and are positioned in the same plane, in which the first planar body further comprises a conductive element disposed on the first surface of the first planar body and in contact with each of the plurality of conductors to permit current flow from the planar conductive body to the plurality of conductors;
• and
• a plurality of transverse rods coupled to each of the plurality of lenses and effective to retain the plurality of lenses substantially parallel to each other.