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Glossary terms about Voltage

Voltage
The voltage between two points is the electrical force that would drive an electric current between the two points.

▼2 more terms contain Voltage



16 pages mention Voltage

Acceleration voltage vs. specimen type
In theory, an increase in accelerating voltage will result in a higher signal (and lower noise) in the final image (micrograph). 
Background information - What is scanning electron microscopy?
This is somewhat surprising at first glance, given the contrast between the simple technology of the LM and the complex electronics, vacuum equipment, voltage supplies and electron optics system of electron microscopes. 
Electron gun
Thermoelectrons produced by the filament are accelerated through the application of a voltage between the filament and the anode, thus creating an electron beam that streams down the microscope column. 
EM Laboratory Hazards
Some samples may also be a chemical hazard. Electrical: High voltage is present in electron microscopes and other electrical equipment. 
Operation unit
Data such as accelerating voltage and magnification will be visible when the image in freeze mode. 
Principles of SEM operation
Electromagnetic lenses, apertures and beam size  
Risk assessment example: using a SEM
Notes: SEM contains high voltages capable of serious or fatal shocks to individual users. 
Risk assessments
Safety shower/eyewash. Electrical hazards – High voltage equipment Electrocution High voltage components are enclosed. 
Sample insertion and beam activation
While you are waiting for the machine to reach its correct vacuum you can select the electron beam voltage that you will need to use (but don’t turn it on yet). 
Saturating the filament
Instead, electrons are pulled off the cold filament by a strong electrostatic field called an extraction voltage
The electron gun
Electrons that strike the anode are returned to the high voltage power supply via ground. 
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?
Wavelengths of electron beams generated at different accelerating voltages (compare with Table 1) Accelerating voltage (kV) Wavelength (nm) (symbol = λ) 50 0.