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Infrared illuminators are devices that are able to light up an area without humans noticing the extra illumination. These illuminators often work in conjunction with or are directly mounted on security cameras, because black-and-white cameras are sensitive to infrared light. With the extra light infrared illuminators produce, security cameras are able to record with clarity, even when ambient light is lacking. These illuminators also are economical, because little energy is needed to power them and the light-emitting diodes (LEDs) that produce the light last up to 100,000 hours.
Many stores, streets and buildings have security cameras to protect the area from theft or destruction of property. When nighttime comes, the owners of the property can do one of two things. They can either turn on lights that help the cameras see, or use infrared illuminators. While the first option would work, the very presence of visible lighting would likely make the security camera more conspicuous. Infrared illuminators would not be seen and the cameras would be less obvious.
Infrared illuminators function by using the long-wavelength, or far infrared spectrum of light. People see light that is known as visible light, but infrared light sits outside this range on the spectrum. This means that, while light is shining on an area, the human eye will be unable to perceive it. While humans cannot perceive the light, some cameras are able to. This allows the camera to generate black-and-white video images, even if there is no visible light to be used.
Black-and-white security cameras must be used in conjunction with infrared illuminators, because they are the only cameras that are sensitive to the infrared spectrum. Color cameras depend on ambient light for color images, so they cannot see infrared light. If a color camera has a black-and-white mode, then the camera can be used, as long as it is set to black-and-white mode.
There is a way for criminals to thwart infrared cameras, and that is by using another infrared light. If one shines an infrared light at an infrared camera, it will cause the camera to capture a glare instead of capturing an image of the person shining the light. To combat this, many security cameras are built with infrared filters.
They do not need to produce ambient light and do not require extra energy for incandesce, so infrared illuminators require very little power. This allows businesses to shine the lights, without having to worry about high overhead costs. Most of the illuminators will last around 100,000 hours, making them even more economical.