| 摘要 |
PURPOSE:To increase the amount of ions introduced into the mass spectrometer and enhance the analysis sensitivity by arranging anion focusing lens between front and rear orifices in the mass spectrometer. CONSTITUTION:An electromagnetic lens 12, whose luminous axis is a line connecting the respective centers of a nozzle 9 and skimmer 8, is arranged, as an ion focusing lens, inside the first chamber 7. A part of plasma under atmospheric pressure is absorbed into the first chamber 7 from the nozzle 9 to form molecular beams. Though the molecular beams are likely to spread out at right angles to themselves, only ions in the molecular beams are selectively prevented from spreading out by the mutual action between the magnetic field of electromagnetic lens 12 and the movement of ions, which are accelerated with a few V of positive potential of plasma to the nozzle 9, caused by electron scattering. This composition serves the first chamber 7 as a separator in which molecular beams are separated into neutral molecules and ions, and then ions in condensed conditions are projected into the inside of the second chamber 4. |
