Time of flight mass spectrometer and detector therefor

Abstract From the Canadian patent

An ion detector (27) for use in a time-of-flight mass spectrometer (1) is disclosed. The ion detector (27), which has an extended dynamic range comprises collection electrodes (36, 38; 39) of different surface areas. In one embodiment the collection electrodes (36 38; 39) are formed in an array , consisting of a larger plate-like collection electrode (36 38) and a smaller , plate-like collection electrode (39). Microchannel multiplier plates (31 32) , may be arranged in front of the collection electrodes (36 38; 39). In an , alternative embodiment the collection electrodes consist of a grid (42) or more preferably, a wire electrode (50) disposed in front of a plate-like electrode (43).