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A conductive enclosure used to block electrostatic fields is also known as a Faraday cage. The amount of reduction depends very much upon the material used, its thickness, the size of the shielded volume and the frequency of the fields of interest and the size, shape and orientation of holes in a shield to an incident electromagnetic field.
A Faraday cage or Faraday shield is an enclosure used to block some electromagnetic fields. A Faraday shield may be formed by a continuous covering of conductive material, or in the case of a Faraday cage, by a mesh of such materials. Faraday cages are named after scientist Michael Faraday, who first constructed one in 1836. [1]
The E-T secondary electron detector can be used in the SEM's back-scattered electron mode by either turning off the Faraday cage or by applying a negative voltage to the Faraday cage. However, better back-scattered electron images come from dedicated BSE detectors rather than from using the E–T detector as a BSE detector.
There is a relatively short practical scanning range (order of 1000s micrometer) along any direction. The housing is important to shield electromagnetic noise (Faraday cage), acoustic noise (anti-vibrating tables), air flow (air isolation cupboard), and static charge on the sample (ionizing units).
A variant of this is the high altitude EMP (HEMP) nuclear weapon, designed to create the pulse as its primary destructive effect. Non-nuclear electromagnetic pulse (NNEMP) weapons. Sources of repetitive EMP events, sometimes as regular pulse trains, include: Electric motors; Electrical ignition systems, such as in gasoline engines.
The calculated data allows using C 60 fullerene as a Faraday cage, [13] which isolates the encapsulated atom from the external electric field. The mentioned relations should be typical for the more complicated endohedral structures (e.g., C 60 @C 240 [ 14 ] and giant fullerene-containing "onions" [ 15 ] ).
Four-conductor shielded cable with metal foil shield and drain wire. Coaxial cable. Electronic symbol for a shielded wire. A shielded cable or screened cable is an electrical cable that has a common conductive layer around its conductors for electromagnetic shielding. [1]
In electrostatics, a conductor is a three-dimensional equipotential region. In the case of a hollow conductor (Faraday cage [4]), the equipotential region includes the space inside. A ball will not be accelerated left or right by the force of gravity if it is resting on a flat, horizontal surface, because it is an equipotential surface.