US Patent 7999223 Multiple ion isolation in multi-reflection systems

This invention relates to a method of operating a charged particle trap in which ions undergo multiple reflections back and forth and/or follow a closed orbit around, usually, a set of electrodes. The invention allows high-performance isolation of multiple ion species for subsequent detection or fragmentation by deflecting ions out of the ion trap according to a timing scheme calculated with reference to the ions' periods of oscillation within the ion trap.