Patent ID: 9324551
Filing Date: 2016-04-26
CPC Classification: H01J

Claim Text:
1. A method of operating an ion guide, the ion guide comprising: (a) an electrode unit including a number N, wherein N is an integer not less than 6, of rod-shaped or plate-shaped electrodes arranged so as to surround an ion optical axis, the electrode unit transports ions to a subsequent stage while focusing ions by action of a high frequency electric field formed in a space surrounded by said N electrodes, (b) a voltage generator configured to generate a first square wave voltage of predetermined frequency and predetermined amplitude and a second square wave voltage of opposite phase to said first square wave voltage as voltages for forming the high frequency electric field in the space surrounded by said N electrodes, and (c) a connection switch configured to switch the electrode unit between a first state and a second state; the method comprising: wherein in both said first and second states, each of the sets includes either only one of the electrodes or a plurality of circumferentially adjacent electrodes electrically connected to one another.