Scanning Electron Microscope (SEM)
Physics & Mathematics
A scanning electron microscope (SEM) is a type of electron microscope that produces images of a sample by scanning the surface with a focused beam of electrons. The electrons interact with atoms in the sample, producing various signals that contain information about the sample's surface topography and composition. The electron beam is scanned in a raster scan pattern, and the beam's position is combined with the detected signal to produce an image. SEM can achieve resolution better than 1 nanometer.
The image is a butterfly wing in large magnification, which shows its nanostructure to reflect particular color on the wing. It is extremely good for STEM programs in secondary schools to investigate nature specimens in nanoscale.