| 摘要 |
PROBLEM TO BE SOLVED: To enable accurate identification of mass by preventing a mass peak from being shifted by amplitude of high frequency voltage upon ion trapping. SOLUTION: A control part 5, when high frequency voltage applied to a ring electrode 11 is in a particular phase position, controls a ring voltage generator 4 to stop the voltage, and after a predetermined period, applies voltage to end cap electrodes 12, 13 for drawing ions. When the high frequency voltage is stopped in a particular phase position, the ring voltage is converged to a certain voltage after a predetermined period of time has passed, regardless of past voltage amplitude. Using this timing, ion can be drawn from an ion trap 1, thus aligning initial energies to prevent mass peak from being shifted. COPYRIGHT: (C)2004,JPO&NCIPI |
