Anti-white Light Interference

One problem with PIR sensors is that visible light can trigger the pyroelectric element of the sensor. PIR sensors generally have an inherent vulnerability to bright white light, for instance car headlights or bright flashlights. Specifically, when a bright white light is shined on the pyroelectric element, it introduces a signal in this element that, when amplified, will seem to be a legitimate target to the processing component of the sensor.

It would be advantageous to provide a motion detecting method and system that provides significantly improved white light immunity while obviating intentional blinding of the sensor by an intruder.