Patent ID: 7456737

Claim:
An intrusion detection system comprising: first and second sensors, each of said first and second sensors having a horizontal field of view; a housing, said first and second sensors mounted within said housing wherein a portion of said housing is moveable relative to at least one of said first and second sensors to thereby define first and second relative positions wherein, when said housing portion and said first and second sensors are in said first relative position with respect to each other, said first and second sensors define a combined horizontal field of view having a first angle and wherein, when said housing portion and said first and second sensors are in said second relative position with respect to each other, said first and second sensors define a combined horizontal field of view having a second angle less than the first angle; a biasing member configured to automatically apply a biasing force to one of said sensors and said housing portion towards one of said first and second relative postitions; and an actuator configured to move one of said sensors and said the housing portion against the biasing force of the biasing member towards the other of said first and second relative positions.