Are PIR detectors most sensitive to motion toward and away from the detector?

PIR (Passive Infrared) detectors are designed to detect changes in infrared radiation, which typically occurs when a warm body, such as a person or animal, moves through the detection field. These detectors are most sensitive to motion across the detection pattern rather than directly toward or away from the detector.

When motion occurs across the field of view, the PIR sensors can better detect the changes in infrared energy levels, leading to more effective triggering. Movement directly toward or away from the sensor may not generate the same level of detectable infrared change, as it can pass through a smaller portion of the sensor elements, reducing the likelihood of detection.

Understanding this principle is essential for effective placement and utilization of PIR detectors within security systems. Proper installation and positioning will maximize their efficacy in detecting unauthorized movements.