The Opal addressable beam detector is an intelligent reflector
type linear optical beam smoke detector designed to operate
with Notifier addressable fire alarm systems. It operates
primarily on the principle of light obscuration utilising infra-red
light.
The Infra-Red transmitter generates a beam of light towards
a high efficiency reflector. The reflector returns the beam to
the receiver where an analysis of the received signal is made.
The change in the strength of the received signal is used to
determine the alarm condition.