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Electronic
Article Surveillance Systems |
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Electronic
Article Surveillance (EAS) Anti-theft Systems are designed to prevent
unauthorized removal of items from shops, supermarkets, libraries, etc.
They
can also be used in a wide variety of other locations, such as business
premises and even hospitals. An
EAS solution consists of detection systems at the checkout or exit of a
store (or business premises), together with small electronic tags or
labels that are affixed to the protected items.
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How
they work
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EAS
Systems operate from a simple principle, regardless of the manufacturer or
the specific type of technology used:
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A
transmitter sends a
signal (1) at defined frequencies to a receiver. This creates a "surveillance
area", usually at a checkout aisle or an exit in the case of
retail stores. Upon entering the area, a tag or label (2) with special
characteristics creates a response, which is detected by the receiver
(3).
The exact means by which the tag or label responds is a
distinctive part of different EAS systems technologies
The
tags or labels are either turned-off (deactivated), or removed, at the
point of purchase. If an item
is taken through the surveillance area with an active label or tag still
applied, an alarm will sound.
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What
they look like |
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The
detection systems are usually visible and recognizable as flat panels,
loops, or pillars at or near the store exit (on one or both sides of the
exit) or checkout aisle. Occasionally,
the detection unit is built into the floor or in the
ceiling or around the edge of a doorway.
The detection electronics are usually concealed in a cupboard or
behind a facia in the store or the checkout, or they may be integrated
into the panels.
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Point
of sale deactivation |
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Another
component of EAS systems is equipment for the deactivation of tags at the
point of sale. Deactivators use special signals to prevent or modify the
response of the tags or labels, so that they are no longer detected in the
surveillance area. Many
deactivators have a tag/label sensing circuit built-in (essentially a
lower powered version of a detector panel) that automatically starts the
deactivation signal. Other
deactivators are triggered by an operator pressing a button or are
triggered automatically by linking the deactivator to a bar code scanner
or similar device.
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