A method for the chromatic aberration correction of a laser time of-flight mass analyzer

The new ion-optical system of the laser time-of-flight (TOF) mass spectrometer on the basis of two tandem wedge-shape reflectors has been offered and implemented. A new method of correcting chromatic aberration by the ion energy was proposed that used a wire electrode unit with adjustable potentials. This unit allows one to adjust the local TOF of the ions in a narrow energy range +/- 1-2% within the total ion packet with an energy spread of +/- 20%. The method reduces the duration of the ion packets by up to 1.5 ns, which enables us to obtain the restriction of resolution at a level not worse than R similar to 10,500 for a TOF of similar to 35 mu s. The aim of the project is to increase the separation of isobaric ions to improve the limit of detection of the laser TOF-MS for the analysis of high-purity samples.