Mass-resolved ion microscope imaging over expanded mass ranges using double-field post-extraction differential acceleration

摘要

A modified post-extraction differential acceleration (PEDA) technique employing two pulsed electrodes was used to demonstrate mass-resolved stigmatic imaging over a broad m/z range. By varying the pulse voltages, a potential energy cusp was introduced into the ion acceleration region of an imaging mass spectrometer, creating two m/z foci that were tuned to overlap at the detector plane. This resulted in two focused m/z distributions that stretched the mass-resolved window with m/Δm ≥ 1000 to 165 Da without any loss in image quality; a range that doubled the 65 Da achieved under similar conditions using the original PEDA technique.