Abstract: 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 at least one microchannel plate electron multiplier (42, 32) together with first and second collection electrodes (36, 38; 39). The second collection electrode (36, 38) is arranged such that in receives more electrons per ion entering the ion detector (27) than the first collection electrode (39). 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). In an alternative embodiment a second microchannel plate electron multiplier is arranged between the first collection electrode (46) and the second collection electrode (47).

Abstract: A method of correcting mass-spectral data acquired using a time-of-flight mass spectrometer (1) is disclosed comprising recognizing in an observed mass spectrum the mass peaks and determining the observed peak area and mass centroid. Then, using a correction table, the observed mass centroid is corrected for the effect of detector dead-time. The correction table is generated using a Monte Carlo simulation.

Abstract: 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).