Detection of very large molecular ions in a time-of-flight mass spectrometer
US5463218A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 19, 1994 |
| Grant date | Oct 31, 1995 |
| Priority date | — |
| Expiry date | May 19, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J49/025
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The invention relates to a method and a device for detecting very large molecular ions in a time-of-flight mass spectrometer, in which the molecules to be detected first fall with high energy (>8 keV) onto a conversion dynode and are then converted into an electronic signal in a sequence of stages. The rnolecules to be detected are at least partly converted into small (<200 u) positive and negative secondary ions on the conversion dynode. The secondary ions formed are accelerated, optionally positive or negative, onto a microchannel plate, where they are converted into electrons. The electrons are amplified in the microchannel plate and then accelerated onto a scintillator. The electron signal is converted into a light signal in the scintillator, being further amplified. A connecting fiber-optic light guide supplies the photons to a photomultiplier, in which they are converted in customary manner into a signal which can be evaluated electronically.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.