Microscope Imaging Mass Spectrometry With A Reflectron

A time-of-flight microscope imaging mass spectrometer incorporating a reflectron was used to image mass-resolved ions generated from a 270 mu m diameter surface. Mass and spatial resolutions of 8100 +/- 700 m/Delta m and 18 mu m +/- 6 mu m, respectively, were obtained simultaneously by using pulsed extraction differential acceleration ion optical focusing to create a pseudo-source plane for a single-stage gridless reflectron. The obtainable mass resolution was limited only by the response time of the position-sensitive detector and, according to simulations, could potentially reach 30 200 +/- 2900 m/Delta m. The spatial resolution can be further improved at the expense of the mass resolution to at least 6 mu m by increasing the applied extraction field. An event-triggered fast imaging sensor was additionally used to record ion images for each time-of-flight peak resolved during an experimental cycle, demonstrating the high-throughput capability of the instrument. Published under license by AIP Publishing.