2D-O1-0950 PDF
A new Type Mass Analyzer using Two Rotating Electric Fields
Many types of mass analyzers are widely spread and used in various fields. Well known theory of magnetic fields, electrostatic fields, and electrodynamic fields are their basic principles of operation. Introducing two rotating electric fields, we investigated a compact mass analyzer which can analyze ions of wide mass range continuously. Two rotating electric field (REF) units of the analyzer are lined in tandem with some space between them, and are coaxial with the optical axis of an ion beam. Two REF units are identical and each has multiple electrodes which are connected to sinusoidal signals to generate rotating electric fields inside these units. When we choose the period of the electric field rotation to be equal to the transit time of specified mass ions in each REF unit, and fix the phase angle of the downstream REF unit different by 180 degrees from the upstream REF unit, the analyzer shows a beautiful phenomenon to us. Ions enter the upstream unit first, diverge outward by lateral force of the rotating electric field and leave the unit at points apart from the central axis. Entering the downstream unit, ions converge inward by reversed lateral force caused by the phase angle difference.