Abstract: A mass spectrometer comprising: a pulsed ion source for generating pulses of ions having a range of masses; a time-of-flight mass analyzer for receiving and mass analyzing the pulses of ions from the ion source; and an energy controlling electrode assembly located between the pulsed ion source and the time-of-flight mass analyzer configured to receive the pulses of ions from the pulsed ion source and apply a time-dependent potential to the ions thereby to control the energy of the ions depending on their m/z before they reach the time-of-flight mass analyzer. Mass dependent differences in average energy of ions can be reduced for injection into a time-of-flight mass analyzer, which can improve ion transmission and/or instrument resolving power.

Abstract: A mass spectrometer comprising: a pulsed ion source for generating pulses of ions having a range of masses; a time-of-flight mass analyzer for receiving and mass analyzing the pulses of ions from the ion source; and an energy controlling electrode assembly located between the pulsed ion source and the time-of-flight mass analyzer configured to receive the pulses of ions from the pulsed ion source and apply a time-dependent potential to the ions thereby to control the energy of the ions depending on their m/z before they reach the time-of-flight mass analyzer. Mass dependent differences in average energy of ions can be reduced for injection into a time-of-flight mass analyzer, which can improve ion transmission and/or instrument resolving power.