In access control, a beam detector, also known as a photo beam detector or infrared beam, is a sensor that detects the presence of an object or person by detecting the interruption of an infrared beam. It functions by emitting an infrared beam across a space and triggering an alarm when the beam is broken.
How it works:
Beam detectors use a transmitter that emits a beam of infrared light. A receiver is placed on the opposite side of the beam, and any object that passes through the beam and obstructs it will cause the receiver to detect a change in the light pattern, triggering an alarm.
Types of Beam Detectors:
- Infrared Beam Detectors: These are the most common type and use infrared light to detect the presence of an object.
- Reflective Beam Detectors: These use a reflector to bounce the infrared beam back to the receiver, allowing for detection of objects on both sides of the beam.
Applications in Access Control:
- Doorway Detection: Beam detectors can be used to detect when a person walks through a doorway, which can be used to trigger an alarm, unlock a door, or activate other systems.
- Driveway Alert: Beam detectors can be used to detect a person or a car passing through a driveway, which alerts the indoor receiver.
- Object Detection: Beam detectors can be used to detect the presence of vehicles or objects in certain areas.
- Boundary Detection: They can also be used to create a virtual boundary and detect when an object crosses it, such as in perimeter security.