Method and apparatus for improved sensitivity in a mass spectrometer
US7259371B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Dec 22, 2005 |
| Grant date | Aug 21, 2007 |
| Priority date | — |
| Expiry date | Dec 22, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J49/063
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
In a mass spectrometer, ions from an ion source pass through an inlet aperture into a vacuum chamber for transmitting prior to mass analysis by the mass analyzer. The configuration of the inlet aperture forms a sonic orifice or sonic nozzle and with a predetermined vacuum chamber pressure, a supersonic free jet expansion is created in the vacuum chamber that entrains the ions within the barrel shock and Mach disc. Once formed, at least one ion guide with a predetermined cross-section to essentially radially confine the supersonic free jet expansion can focus the ions for transmission through the vacuum chamber. This effectively improves the ion transmission between the ion source and the mass analyzer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.