Patent ID: 6937151

Claim:
A perimeter barrier system comprising: a barrier element; a mounting for mounting the barrier element for intentional limited movement, the mounting having a biasing system for biasing the barrier element towards a first position, and wherein upon a disturbance of the barrier element caused by an attempt to breach the perimeter barrier system, the barrier element moves intentionally against the bias of the biasing system towards a second position; a waveguide located in proximity to the barrier element; a light source for launching light into the waveguide so that the light can travel through the waveguide; a detector for detecting light which has traveled through the waveguide; and wherein upon the disturbance, the barrier element moves towards the second position to cause a movement or loading of the waveguide which alters a parameter of the light traveling through the waveguide, and whereupon the detector detects the changing parameter of the light which has traveled through the waveguide to thereby provide an indication of an attempted breach of the perimeter barrier system.