Quadrupole mass filter and quadrupole mass spectrometrometer
US10707066B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 2, 2015 |
| Grant date | Jul 7, 2020 |
| Priority date | — |
| Expiry date | Dec 2, 2035 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J49/4215
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Four main rod electrodes included in a main electrode section are disposed in a rotationally symmetric manner around an ion optical axis. Among four pre-rod electrodes included in a pre-electrode section disposed in front of the main electrode section, two are in contact with a circle of a radius r0, whereas the other two are disposed to be in contact with a circle of a radius R0 larger than r0, resulting in rotational asymmetry around the ion optical axis. Accordingly, a shape of acceptance on an x-y plane regarding positions of ions in the pre-electrode section becomes elliptical. This allows the shape of the acceptance to become gradually flat as the ions travel along the ion optical axis, reducing a mismatch between emittance of incoming ions and the acceptance on a receiving side, and relieving ion loss during ion introduction.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.