Patent ID: 6441369
Filing Date: 2002-08-27
Classification: H01J

Abstract:
A tandem time-of-flight mass spectrometer comprising:a) a pulsed source of ions that focuses a packet of ions substantially within a predetermined mass-to-charge ratio range onto a focal plane in a flight path of the ions; b) an ion selector that receives the focused packet of ions, wherein the ion selector selects ions substantially within the predetermined mass-to-charge ratio range and rejects substantially all other ions; c) an ion fragmentor positioned in the flight path of the ions, the ion fragmentor fragmenting a fraction of the ions; d) a pulsed ion accelerator positioned in a flight path of the selected ions and fragments thereof after the ion fragmentor, wherein the pulsed ion accelerator accelerates the selected ions and fragments thereof; and e) an electrode positioned in the flight path of the accelerated selected ions and fragments thereof after the pulsed ion accelerator, the electrode being biased with a time varying bias voltage that increases the kinetic energy of the fragments relative to the selected ions.