The lights are off as you drive up to your home, and that’s odd because you left the lights on prior to leaving. Then you notice that the side door is ajar. Your first reaction should be to call the police. Your next should be to stay put in your vehicle. But what if someone is still lurking in the darkness? You could be waiting for help only to have a bad actor creep up on you using the cover darkness. The FLIR One can help you spot attackers before they get anywhere near you. Now you can have the advantage in darkness.

The FLIR One is a thermal-imaging device that attaches to any iPhone or Android smartphone or tablet. Not only is it handy for detecting overloaded circuit breakers, inefficient heat insulation in your home, the amount of propane remaining in your BBQ grill tank, the cat that climbed too high into a tree—to name just a few uses—but, more importantly, it can also detect people hiding in the shadows, in the shrubs around your home or waiting for you in a pitch-black room. It is as much a practical tool to have around the home as it is a self-defense tool.

The FLIR One uses a Lepton camera and MSX technology to capture still images and video of things and people that range in temperature from -4 to 248 degrees Fahrenheit. MSX technology takes a thermal image and a visible image, extracts the detail from the visible image and combines the extracted image with the thermal image to provide a look at what it is you are really seeing. Is that really the neighbor’s dog in your backyard or is it a spring bear raiding your bird feeder? But maybe the situation is more sinister. It could be a person in your backyard crouching behind bushes, perhaps stalking you and your family, watching and waiting for a moment to penetrate your home and do harm. The FLIR one helps keep you safe and aware by taking images in milliseconds without waiting— similar to the speed of the camera built into your phone. You can watch it in real time as you scan your backyard for possible intruders.

Easy Add-On

FLIR One for iPhone
After you’ve downloaded the FLIR One app and installed the device, you’ll be able to identify objects and people via highly sensitive temperature variations.

The FLIR One unit is about 1-inch tall, 2 inches wide and as thick as your smartphone. It has a battery that needs to be charged prior to use, then it plugs into the USB or charging port of your phone and uses your phone’s camera to take still images and video. You’ll also need to download the free FLIR One app so your phone and the device can pair up properly. Another great thing is that newer phones offer better picture quality, especially at distance, making it easier to identify the heat signature of people and animals with the FLIR One device.

The FLIR One can be used at any time of the day or night since temperature variances constantly occur. The FLIR One also provides color palettes—black/white, wheel, rainbow, contrast, arctic, hot/cold and iron—so a user can adjust the image. It also features panorama, time-lapse and close-up functions.

Law enforcement personnel already use thermal-imaging devices for surveillance activities, fugitive searches, search and rescue operations, locating evidence and more. First and foremost, thermal imagers help protect officers when arriving at a scene. But officers and civilians alike can use thermal imagers to scan a location from a safe distance to identify people or pets, preventing an ambush. The FLIR One is a compact device that does not require a Department of Defense budget—it retails for around $250.

For more information, visit or call 866-354-7911.

This article was originally published in ‘Personal & Home Defense’ #187. For information on how to subscribe, please email or call 1-800-284-5668.

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