Infrared light is described as light that is invisible to the naked eye. It has a much longer wavelength than that of normal light and a lower frequency which is why it us undetectable without the presence of technology. Such technology can take the form of infrared security cameras which use infrared LED (light-emitting diode) lights located peripheral to the camera lens so that the camera can capture images even in total darkness. However, the camera must detect something in order to produce an image and even in areas of zero visibility there are other distinguishable forms of energy. One such form of energy that all objects in the universe produce unless they have a temperature of absolute zero – a virtual impossibility – is infrared light radiation. Simply put, an infrared camera can detect such light energy using infrared LED lights and then transfer the data it collects into an image visible on a screen.
Infrared security cameras are not day/night cameras and should not be confused as such. This type of camera does not use infrared light technology and therefore requires a minimal light source within the visible spectrum to produce a quality video feed.
Likewise, an infrared camera can produce a color picture under the same conditions. However, as light diminishes it will automatically switch to infrared light mode producing a black and white image on a monitor. The amount of light in a camera’s environment is referred to by the Latin term “lux” and a worthwhile infrared camera can produce a quality, albeit black and white image, in conditions of 0.0 lux. This is where it differs from a day/night camera which in the absence of light can’t detect anything at all.
The quantity of infrared LED lights present in the camera will determine the detection range of an infrared camera in total darkness. Some of the more advanced technological hardware on the market can monitor objects and individuals as far as 150 feet into a complete dark void. However infrared cameras are designed for both indoor and outdoor use and as such may come with either short or long range infrared LED lighting accordingly.