Particle beam system with dynamic focusing
US6130432A · kind A · utility
7Cited by
2References
17Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 13, 1999 |
| Grant date | Oct 10, 2000 |
| Priority date | — |
| Expiry date | Apr 13, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2237/3175
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A magnetic lens having a lens bore for the passage of a particle beam includes a dynamic focus coil that is positioned outside the lens bore and within the pole piece that shapes the lens field, so that the magnetic flux lines from the dynamic focus coil all end on the pole pieces of the lens and the shape of the lens field between the pole pieces has its magnitude changed by the current passing through the dynamic focus coil, but the field shape is not changed, thus changing the focal plane of the beam without moving the beam transversely with respect to the system axis.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.