How Thermal Imaging Works
Background
Thermal imaging is a type of scientific imaging that works by detecting infrared radiation given off by objects, animals and people. This detected infrared radiation is then mapped, creating an image. Due to the fact that infrared radiation is outside the visible range of the electromagnetic spectrum, thermal imaging makes it possible to create an accurate image of the environment with or without any visible light. The amount of infrared radiation emitted by any given person, animal or object is directly related to its temperature. As a result, thermal imaging is tremendously effective at finding warm-blooded animals and people in the dark, as they stand out extremely well in the thermal image against the cold background.
The Science
Thermal imaging works by capturing the infrared radiation emitted by any object, person or animal. Anything above the temperature of 0 degrees Kelvin (about - 469 degrees F), also known as absolute zero, emits some measure of infrared energy. To get an accurate reading of temperature using thermal imaging, the camera must run a series of algorithms based upon the infrared radiation emitted by an object and its emissivity. Because no object radiates 100 percent of its temperature as infrared radiation, thermal imaging cameras use emissivity, the percentage of the thermal radiation emitted to the true temperature of the object to provide a more accurate read of the object's temperature. Using these algorithms, the thermal imaging cameras can create an image of the environment without the need for visible light with fairly accurate temperature readings.
Uses
Originally developed for military use, thermal imaging's ability to provide an accurate picture of people without the need for any visible light continues to make it a useful tool for military use. However, its role has also expanded into the realm of security, being a key part of advanced security systems. Thermal imaging is also being used by electronics maintenance crews who can detect hot points in power lines and repair them before they cause a power failure. Fire fighters have also made use of thermal imaging which allows them to find people behind heavy smoke and also locate the base of fires. Another common use for thermal imaging is to find heat leaks in large cooling or heating systems, enabling the problems to be repaired and to increase the system's overall efficiency. These are just a few uses of thermal imaging. Many more are being found as technology allows thermal imaging cameras to become smaller, more accurate and more affordable.
Tags: infrared radiation, thermal imaging, radiation emitted, imaging cameras, infrared radiation emitted, thermal imaging