| 摘要 |
PROBLEM TO BE SOLVED: To remove a great amount of mass as undersized and separate selected ion mass as desired by establishing a trap field in an ion trap to generate the first auxiliary dipole field in the trap. SOLUTION: A quadruple ion trap mass spectrometer is used to establish a trap field in an ion trap for trapping ions in the first continuous mass range. An auxiliary dipole field is applied to the ion trap, while modulating the trap field, to remove undesired ions from the ion trap. The auxiliary dipole field comprises plural frequency components, which have spaces changed over a frequency range of dipole voltage. The frequency range of the dipole field is suitably divided into continuous subranges. Spaces between the frequency components in the subranges are substantially constant. |
