Thermal imagers are instruments that create pictures of heat rather than light. They measure radiated IR energy and convert the data to corresponding maps of temperatures. Today, instruments provide temperature data at each image pixel and, typically, cursors can be positioned to each point with the corresponding temperature read out on the screen or display. Images may be digitized, stored, manipulated, processed and printed out.

All objects have a certain temperature and emit waves of energy called infrared radiation. Hot objects emit more energy than cold objects. A thermal imager translates these energy waves into a viewable image, which shows a “heat picture” of a scene. The pictures above demonstrate the difference between visable light what the naked eye can see and a thermal image. Move your cursor over the images and you will notice the change between the visable and thermal images.