Patent · US Active

Objective lens

US8362443B2 · kind B2 · utility

1Cited by

14References

20Claims

0Family size

Assignee

Carl Zeiss Microscopy GmbH · DE

Inventor

Volker Drexel · Oberkochen, DE

Key dates

Filing date	Apr 18, 2012
Grant date	Jan 29, 2013
Priority date	—
Expiry date	Apr 18, 2032

Classification

Technology area (CPC H)Electricity
CPC primaryH01J37/1471
WIPO fieldElectrical machinery, apparatus, energy
WIPO sectorElectrical engineering

Abstract

An objective lens for focussing charged particles includes a magnetic lens and an electrostatic lens whose components are displaceable relative to each other. The bore of the outer pole piece of the magnetic lens exhibits a diameter Da which is larger than a diameter Di of the bore of the inner pole piece of the magnetic lens. The following relationship is satisfied: 1.5·Di≦Da≦3·Di. The lower end of the inner pole piece is disposed in a distance of at least 2 mm offset from the inner end of the outer pole piece in a direction of the optical axis.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.