GAS PHASE ION SOURCE FOR FLIGHT-TIME MASS SPECTROMETERS WITH HIGH MASS RESOLUTION AND LARGE MASS RANGE

摘要

In order to achieve a high mass resolution in a time-of-flight mass spectrometer with gas phase ion source, the initial-speed components in the acceleration direction of the ions must be kept small. This can be achieved in that the gas or ion beam to be investigated traverses the ion source at right angles relative to the acceleration direction. If acceleration direction and flight direction of the gas or ion beam to be investigated are not parallel, then the flight path is loaded with less gas ballast, the dynamic range of the mass spectrometer being increased as a result. The mass range of such an ion source is limited by the fact that heavy ions can be deflected too far from the axis of the ion source and can get lost as a result. When the deflection field is already located in the acceleration path, the mass range of this ion source can be expanded significantly. IMAGE