![[logo] US EPA](http://www.epa.gov/epafiles/images/logo_epaseal.gif){kind=logo}
Scanning Electron Microscope
A Zeiss DSM962.
Scanning Electron Microscopy involves the manipulation of an electron beam that is scanned across the surface of specially prepared specimens to obtain a greatly enlarged, high-resolution image of the specimen's exposed structure.
Specimen can be observed whole for assessing external structure or freeze-fracture techniques can be used to image internal structures.
The Zeiss DSM962 has a working magnification range of from 4x to 300,000x in user selectable increments at a resolution of 4 nm and working accelerating voltages from 490V to 30kV.
The vacuum system consists of a differential pump system with a turbomolecular pump and a 2-stage rotary ruffing pump.
Sample SEM output (See the big picture 86k).The SEM is a fully digital, microprocessor-based system with computer controlled electron optics.
There is TV-rate image acquisition to framestore with variable frame size from 256 x 256 x 8 for x-ray dot mapping applications to 2048 x 2048 x 8 for high resolution imaging, documentation and archiving of scanned images.
A 600 mbyte read/write optical disk drive provides for archival storage of images. Images may be transferred via electronic media to image processing software packages or printed to either a high resolution video printer or 4x5 film camera.
A cryostage system is directly attached to the vacuum chamber to provide for cryopreservation of specimens, freeze-fracture preparation, and sputter coating of samples. The system has resident image processing and image analysis software manipulation and analysis of digital images.
[ ORD Home | NHEERL Home ]