Passive infrared intrusion detection system

摘要

A passive infrared intrusion detector has: a multi-faceted parabolic reflector for dividing a target controlled area into a plurality of optically divided detection zones, for collecting infrared rays emitted from an object within the controlled area; a passive infrared intrusion sensor combined with the reflector to detect the collected infrared rays; a first means for generating a pulse when an absolute value of an output of the passive intrusion sensor exceeds a reference value; and a second means for generating an alarm signal when predetermined pulses are received from the first means within a predetermined period. A pulse width discriminator is used to eliminate narrow noise pulses.