What is the role of the lens on a PIR (passive infrared) sensor?
(Figure: Example PIR sensor)

Question

What is the role of the lens on a PIR (passive infrared) sensor?   
 (Figure: Example PIR sensor)

Answer

To magnify the infrared signal for higher resolution.

Answer

To direct and segment incoming infrared radiation on the pyroelectric elements.

Answer

To focus visible light onto the pyroelectric elements for better detection accuracy.

Answer

To collect and concentrate infrared radiation onto the pyroelectric sensor for increased sensitivity.

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