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Glossary terms about Resolution

The limit of resolution is the smallest separation at which two points can be seen as distinct entities.

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23 pages mention Resolution

Acceleration voltage vs. specimen type
Therefore, the spatial resolution of micrographs created from those signals will be reduced. 
Background information - What is scanning electron microscopy?
The scanning electron microscope (SEM) provides the competent user with an advantage over the light microscope (LM) in three key areas: resolution at high magnification. 
Beam Adjustment
Sometimes you will need to change the height (z-axis) of your sample (lower for greater depth of focus or to allow tilting; higher for greater resolution) Increase your magnification. 
Concepts - introduction
The use of electrons also impacts on image resolution and image colour, and explains the 3D nature of the micrographs (photos). 
Electromagnetic lenses, apertures and beam size
A smaller aperture is chosen for high resolution work and better  
Electron-beam lithography (E-beam lithography or EBL)
To date, EBL remains the highest resolution patterning tool in lithography, it is widely used in photomask fabrication and low volume production of semiconductor components. 
Generating an image
The greater energy of BSE, compared with SE, means that BSE produced from deeper within the interaction volume are able to escape from the sample and be collected by the BSE detector, so BSE images have lower spatial resolution than SE images. 
High vacuum mode and pump system
This is important as scattering or attenuation of the electron beam will increase the probe size and reduce resolution, especially in the SE mode. 
Zworykin et al. (1942) produced an SEM with a potential resolution of 50 nm. 
Images from electrons
Image from secondary electrons (below lens SE detector) Zincite (ZnO) powder and tabular crytals of shigate (Mn7AL4(SO4)2(OH)228H2O) showing crystal shape and size. (Topographical and morphological information: texture, shape and size.) Image from secondary electrons: high-resolution (InLens SE detector) Gold nanoparticles. 
Introduction - aims and learning outcomes
Magnetic lens system
An optimal aperture diameter should be selected for obtaining high resolution secondary electron images. 
Recommended reading
H. High-resolution electron microscopy (3rd ed. 
Definitions resolution the ability to distinguish closely spaced points as separate points. 
Role of sample height
So, when possible, the WD is kept at 10mm or smaller for high resolution imaging. 
Saturating the filament
These advantages make the FEG SEM a high resolution machine for high magnification work. 
Scan rate and signal to noise ratios
When the SEM is set up for high resolution imaging it will often have a low S/N ratio and appear grainy. 
Specimen chamber
This is important as scattering or attenuation of the electron beam will increase the probe size and reduce the resolution, especially in the SE mode. 
Spot size
The size (cross sectional diameter) that the cone of the beam makes on the surface of the sample affects 1) the resolution of the image and 2) the number of electrons generated (therefore the graininess of the image). 
Troubleshooting: edge effect, charging, sample damage
Increasing the working distance can also help since it produces a larger spot size on the sample for the same beam energy but this has the disadvantage of reducing resolution
What is resolution?
resolution can also be understood as the least distance between two closely opposed points, at which they may be recognized as two separate entities. 
What the SEM can't do
Generally, SEMs are not used for experiments involving liquids, chemical reactions, and air-gas systems although some specialised machines and sample chambers do allow for these experiments. The resolution of the SEM is not high enough to image individual atoms (use a transmission electron microscope).