Method and apparatus for deflecting and focusing a charged particle stream

Abstract

A method and apparatus is disclosed for electrostatic deflection and focusing of a charged particle stream. The apparatus can include plural vertical and horizontal deflection plates, although a single vertical and a single horizontal deflection plate each with a reference potential plane are preferred. Both orthogonal and preferably tilted display screens are employed to receive the deflected beam. The particle stream is injected offset from a centered position and the stream is deflected asymmetrically relative to the attracting deflection plate. Two alternately preferred computer programs are employable to calculate an offset position. A preferred external quadrupole is employed to correct any residual astigmatism in the particle stream. In one embodiment, the apparatus is disposed in a cathode ray tube. A reduced footprint CRT is also disclosed. Methods and apparatuses for an energy filtered electron beam, a mass spectrometer and a mass separator are also disclosed.

Dependencies are inferred from the claim text.