Patent ID: 6080985
Filing Date: 2000-06-27
Classification: H01J

Abstract:
A mass spectrometer, comprising:an ion source including:an electron source for generating a flow of electrons;a gate electrode constructed so as to block said flow of electrons when a potential is applied;a sample introduction means for transporting at least one analyte;an ionization chamber having at least a first input, a second input and at least one output, said first input being for receiving said flow of electrons from said gate electrode, and said second input being for receiving said at least one analyte from said sample introduction means, wherein said flow of electrons ionizes said at least one analyte and said ionized at least one analyte is emitted from said at least one output;a pulsed accelerator;an ion transfer region interposed between said at least one output of said ionization chamber and said accelerator so that ions of said ionized at least one analyte travel from said ionization chamber output, through said ion transfer region and into said accelerator, said ions spatially separating by mass in said ion transfer region before being accelerated by said accelerator;means for controlling said gate electrode and said pulsed accelerator in a time relationship so as to control flow of said ions traveling into said accelerator between accelerator pulses to improve the dynamic range of said mass spectrometer and to selectively accelerate a particular mass range.