Velocity corrected ion extraction in microscope mode imaging mass spectrometry

Microscope mode imaging mass spectrometry requires that ions created in a desorption process are focussed both spatially and according to their mass-to-charge ratio, m/z, onto the plane of an imaging detector. However, it is generally difficult to find techniques that optimize both of these parameters simultaneously. The use of pulsed electric fields allows a second order focussing of the ions according to their m/z value, whilst limiting the loss of spatial resolution, albeit over a limited mass range. Here we present a simple method for rescaling the parameters in a pulsed extraction experiment in order to access different mass ranges, whilst still achieving the benefits of simultaneous optimization of mass and spatial resolutions. (C) 2013 Elsevier B.V. All rights reserved.