Two Samples in the Scanning Electron Microscope (SEM)
The top is paper - actually, lens cleaning paper - in the SEM at 5 KeV. The bottom is silicon pebbles at 5 KeV. Scales are provided on the lower left corners of the images for reference. The samples were sputter-coated with gold for analysis.
Scanning electron microscopes, as the name suggests, are not optical microscopes. An electron emitter scans electrons across a sample in vacuum, and detectors receive the topographical information. These samples therefore must be conductive - thus samples are usually coated, here in gold, but often in other materials like carbon, silver, and platinum through different methods. The images are then viewed on a display screen. Voltage, focus, magnification, astigmatism, brightness, contrast, raster, and other properties can be adjusted through various softwares.
(Image credit: University of Rochester/Optics/Divya M. Persaud. If you reblog this post, please don’t remove my caption/URL/source!)