Electron lens
US3952198A · kind A · utility
16Cited by
2References
3Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 26, 1974 |
| Grant date | Apr 20, 1976 |
| Priority date | — |
| Expiry date | Aug 26, 1994 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J37/153
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An electron lens system comprising a plurality of quadrupole elements, a plurality of octupole elements for correcting the spherical aberrations of said plurality of quadrupole elements, and an axially symmetric lens, arranged at the inlet or outlet side of said quadrupole and octupole elements for varying the focal length of said lens system so that the excitation currents of said plurality of quadrupole elements remain fixed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.