Electronic Article Surveillance (EAS) is a technology used to identify items as they pass through a gated area. Several EAS technologies are widely used today, including electro magnetic, acousto- magnetic, swept radio frequency, and microwave. Each technology functions on the same basic principle: a transmitter sends a signal at defined frequencies to create an electromagnetic field (EMF) that functions as a surveillance area.
This field operates usually between two pedestals placed at the exit of a store or building. Upon entering this area, a security tag or label that has not been removed or deactivated creates a signal in the electromagnetic field, which is detected by a companion receiver. An alarm sounds when the signal is detected.
EAS systems are used anywhere where there is a chance of theft from small items to large. By placing an EAS tag on an item, it is not necessary to hide the item behind locked doors and so makes it easier for the consumer to review the product.