| 摘要 |
A mass spectrometer system with electrospray ion source for generating ions at atmospheric pressure and an ion trap mass analyzer has an improved ion optics for transporting ions from the atmospheric pressure region to the ion trap mass analyzer region. The system comprises a short ion guide having a predetermined characteristic length to radius ratio. The ion guide is coupled to the ion trap mass analyzer via an electrostatic ion optics. The electrostatic ion optics comprises an ion guide extraction optics and an ion trap mass analyzer injection optics. The ion guide extraction optics comprises the ion optical electrode with an aperture that is coupled to an exit of the ion guide and serves as a differential pressure restrictor between the vacuum chamber with the ion guide and the vacuum chamber with the ion trap mass analyzer. The design of the ion optics is tolerant to the mechanical imperfections in the ion optical system and practically eliminates the non-linear matrix effects. |
