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Glossary terms about Filament

Filament
In electron microscopy this refers to the source of electrons for the electron gun: a tungsten wire, a sharpened tungsten crystal, or a lanthanum hexaboride crystal (LaB6).

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14 pages mention Filament

Acceleration voltage vs. specimen type
Accelerating voltage (kV or keV) is the voltage difference between the filament and the anode which accelerates the electron beam towards the anode. 
Detectors
 
Electron gun
The typical thermionic electron gun consists of three parts, the filament, Wehnelt cap and the anode. 
History
 
Principles of SEM operation
filament saturation  
Resolution
 
Saturating the filament
An important factor in using a thermionic gun is understanding saturation of the filament
Scan rate and signal to noise ratios
Tungsten (W) filaments characteristically have low yields of electrons resulting in a low brightness image. 
The electron gun
In the diagram the filament (also called the emitter) is surrounded by the Wehnelt cylinder that closes over the filament assembly and has a small hole in the centre through which electrons exit. 
Virtual SEM - bone
Shows the affect of such settings as accelerating voltage, spot size, Z-depth, filament current, magnification, and astigmatism. 
Virtual SEM - rock
Shows the affect of such settings as accelerating voltage, spot size, Z-depth, filament current, magnification, and astigmatism. 
Virtual SEM - slag
Shows the affect of such settings as accelerating voltage, spot size, Z-depth, filament current, magnification, and astigmatism. 
Virtual SEM - sparkler
Shows the affect of such settings as accelerating voltage, spot size, Z-depth, filament current, magnification, and astigmatism. 
What is resolution?