Scanning electron microscope for visualization of wet samples
US4720633A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 17, 1986 |
| Grant date | Jan 19, 1988 |
| Priority date | — |
| Expiry date | Jan 17, 2006 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2237/2608
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A scanning electron microscope useful for obtaining microscopic data or images of wet specimens is provided with comprises an electron source capable of emitting a beam of electrons; an electron optical vacuum column with means for focussing the beam of electrons; means for scanning the focussed beam of electrons across a specimen; a differentially pumped aperture column attached to the electron optical vacuum column and having at least two walls perpendicular to the sides of the differentially pumped aperture column defining a suitable series of pressure gradients, each wall having an aperture aligned to permit the beam of electrons to pass through said differentially pumped aperture column; a specimen chamber which may be maintained at normal atmospheric pressure; a specimen mount; means of preventing the buildup of negative charge on the surface of the specimen; and a detector and image recording system.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.