| 摘要 |
<p>The invention relates to methods for acquiring sum spectra in a time-of-flight mass spectrometer with pulsed acceleration of the ions orthogonal to the previous direction of flight (OTOF-MS). Each of the sum spectra is obtained from many summed individual spectra. The OTOF-MS usually has an ion storage device which collects the ions temporarily before they are transferred to an ion pulser, which pulses out the ions orthogonally. The invention consists in varying the delay times between the opening of the ion storage device and the pulsed ejection in the ion pulser. This occurs for the individual spectra, which arc added together to form the sum spectrum in such a way that ions in an interesting range of light masses and also those in an interesting range of high masses are both optimally measured.. With this method it is possible that the ions of high masses are measured without losses, while the ions of low masses arc measured with gains in sensitivity by factors of 5 to 20 compared to conventional acquisition methods.</p> |
