Ion source with upstream inner magnetic pole piece
US7589474B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 6, 2006 |
| Grant date | Sep 15, 2009 |
| Priority date | — |
| Expiry date | Jan 31, 2028 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2237/31
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A closed drift ion source is disclosed. The ion source has an open end 1 and a central axis 150 around which are arranged outer magnetic pole piece 3, inner magnetic pole piece 5, anode 2, shield 6 and back magnetic shunt 17. In one embodiment the anode 2 and inner magnetic pole piece 5 are annular. Permanent magnets 7 are located behind the shield 6 and in contact with outer magnetic pole piece 3 and the back magnetic shunt 17. As a result the magnetic field lines pass through the magnetic pole pieces and a mirror magnetic field is set up in the discharge region between them. The inner magnetic pole piece 5 is hollow which facilitates production of the mirror magnetic field.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.