Patent ID: 11848184

Abstract:
An ion guide (20) provided in a first intermediate vacuum chamber includes six rod electrodes (211 to 216) and a voltage generation unit. The six rod electrodes (211 to 216) are in a hexapole arrangement on the ion incident side, and the two rod electrodes (211 and 214) are tilted with respect to the Z-axis in a manner approaching a central axis (201) as they progress in the ion transport direction, so that the four rod electrodes (211, 214, 215, and 216) are in a quadrupole arrangement. The voltage generation unit applies radio-frequency voltages ±V cos ωt whose phases are inverted to each other between adjacent rod electrodes of the six rod electrodes (211 to 216) around the central axis (201), applies a DC voltage U1 to the four electrodes (211, 214, 215, and 216) by which ions pass through them in an excellent manner, and applies a DC voltage U2 different from U1 to the other two rod electrodes (212 and 213).