Abstract: The driver i.e. the electrical control of the Pockels cell is modified from the standardly known H- configuration using the switches S1, S2A; S1A, S2A by adding at least one more switch (S2B; S1B, S2B). This switch can either replace the usually used recharging resistors (R2) or can be placed to these in parallel. It is also possible to use an arrangement using 4 switches (S1A, S2A, S1B, S2B) and no recharging resistors at all. Using such a driver with a Pockels cell pulses can be selected in laser systems more efficiently. Pulse sequences with well defined widths and spacing can be produced for certain applications.

Abstract: Ions passing through inhomogeneous electric fields in the detector of a time-of-flight mass-spectrometer may need different times on different paths(11) between the entrance aperture and the ion-electron conversion surface(3). These errors in flight time can be reduced by properly deforming the conversion surface(3).

Abstract: To achieve a high mass resolution in a time-of-flight mass-spectrometer with gasphase ion source, the initial velocity components in the direction of acceleration of the ion source must be kept small. This can be done by injection the analyte gas or ion beam at right angles to the direction of acceleration into the ion source. When the direction of acceleration and the direction of the analyte gas or ion beam or not colinear, the amount of unwanted gas ballast in the drift space of the time-of-flight mass-spectrometer will be less. This will increase the dynamic range of the mass-spectrometer. The heavier an ion is, the more its path will deviate from the axis of the ion source and if it deviates too far from the axis of the ion source it will be lost. This effect gives the limit of the mass range of such an ion source. If the electrical deflection field for these ions is already within the acceleration region of the ion source, its mass range can significantly be enlarged.

Abstract: A high particle density in the extraction volume of a gasphase ion source and simultaneously a very low particle density in the driftspace of the time-of-flight mass-spectrometer are necessary for high sensitivity and a large dynamic range of the mass-spectrometer signal output. This can be achieved by separating the time-of-flight mass-spectrometer into two or more regions of different pressure, connecting the different regions by gas flow restrictions. A maximum particle density in the extraction volume and simultaneously a minimal particle density in drift space can be achieved by integrating the gas flow restrictions(3,6) directly into the electrodes(1,2) of the ion source.