Particle-optic illuminating and imaging system with a condenser-objective single field lens
US6531698B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Sep 22, 2000 |
| Grant date | Mar 11, 2003 |
| Priority date | — |
| Expiry date | Oct 4, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2237/2802
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The invention relates to a particle-optic illuminating and imaging system with a condenser-objective single field lens (5) and a simple illuminating system which has only two condenser lenses (3, 4). The variation of the size of the illuminated field takes place exclusively by a change of the excitation of the source-side condenser lens (3). The objective-side second condenser lens (4) always has a constant excitation in the TEM mode. The excitation of the source-side condenser lens (3) is the greatest for maximum illuminating field diameter, and on the contrary is reduced for smaller illuminating field diameters. In TEM operation, two crossovers always exist in the illuminating beam path, of which the second is situated between the focal plane of the condenser-objective single field lens and the specimen plane (6).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.