| 摘要 |
PROBLEM TO BE SOLVED: To provide a plasma three-dimensional quadrupole type mass spectroscope suitable for improvement of sensitivity and measuring precision. SOLUTION: High frequency voltage applied to the ring electrode is kept at zero level during the preparation period for measurement (before measurement) 15, linearly increases with time in the period 5 for setup of the ion trap voltage until it reaches the ion trap voltage. This value is kept fixed throughout the ion-trap period 20. Ions are consequently trapped in the ion trap pace, then emitted therefrom in the period of emission 25, and the emitted ions are detected by an ion detector. |
