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Top 5 Innovations in Home Security

        Home & Garden | DIY Safety

2
Motion Detectors
Motion detectors typically use infrared technology.
Motion detectors typically use infrared technology.
iStockphoto/Thinkstock

Early motion detectors that were part of alarm system hardware relied on sound waves to detect changes in an environment. This meant regular household sounds like the swishing of a dishwasher or the ca-chunk of a heater kicking on set it off and caused a lot of false alarms.

Infrared technology eventually replaced the ultrasound, and now it's most commonly found in motion detector floodlights. Motion detectors sense the presence of body heat and reward the intruders with a bright spotlight in their eyes.


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