The
Scanning Electron Microscope (SEM) takes us into a microscopic world
beyond the reach of visible light. Electrons from a metal filament are
collected and focussed, just like light waves, into a narrow beam. The
beam scans across the subject, synchronised with a spot on a computer
screen. Electrons scattered from the subject are detected and create
a current, the strength of which makes the spot on the computer brighter
or darker. This creates a photograph-like image with an exceptional
depth of field. Magnifications of several thousand times are possible.
Normally SEMs are black and white, and are later coloured digitally,
but special colouring techniques involving multiple electron detectors
are possible.
See more techniques:
Aerial Photography
Computed Tomography (CT Scans)
Endoscopy
High Speed Photography
Kirlian Photography
Light Microscopy (LM)
Magnetic Resonance Imaging (MRI)
Molecular Models
Radionuclide Scanning (Gamma Scanning)
Satellite Images
Scanning Electron Microscopy (SEM)
Scanning Tunnelling Microscopy (STM)
Schlieren Photography
Space Photography (NASA)
Thermography
Transmission Electron Microscopy (TEM)
Ultrasound Images
Ultraviolet Photography
X-Rays
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