Linear TOF-MS.
In linear spectrometers using MALDI and TOF, samples are deposited on a metal substrate, capable of holding several hundred analyte spots. Irradiation of these spots by a laser pulse generates a short burst of ions, which are accelerated to a fixed amount of kinetic energy in order to travel down a flight tube. The small ions have a higher velocity than the larger ones, thus producing a time of flight (TOF) spectrum.

Schematic Representation of Basic Components of a Liner TOF Mass Spectrometer