Patent ID: 8796619

Claim:
An orbital trap for trapping ions using an electrostatic field, comprising: an electrode structure defining an internal volume of the trap with at least some of electrode surfaces shaped to substantially follow equipotential lines of an ideal quadro-logarithmic electric potential around a longitudinal axis z, said ideal electric potential having an inner potential canyon, an outer potential canyon, and a low potential passage therebetween; and a trapping voltage supply which provides trapping voltages on the electrodes to generate a trapping electrostatic potential within the internal volume of the trap, said trapping electrostatic potential closely approximates at least a part of said ideal electric potential in at least a part of the internal volume of the trap; wherein said approximated part of the ideal electric potential includes said low potential passage between the inner and outer potential canyons of the ideal electric potential and at least a part of the inner potential canyon adjacent to said passage.