is transmitted in the infrared wavelength ( 1 micron to 100 microns ). You can see by the image above that thermal energy is closely related to visible light in that it travels in a wave. The human eye can only see the narrow middle band of visible light that encompasses all the colors of light in the rainbow. Thermal infrared imagers translate the energy transmitted in the infrared wavelength into data that can be processed into a visible light spectrum video display. Heat transmission between objectsThe first image displays two adults and a child through an infrared thermal imager. After a minute of sitting on the couch the thermal infrared energy of the people is transferred and stored in the couch until they get up. The second image, with no people, shows the fact that all objects radiate heat. The heat from their bodies that transferred to the couch is now being emitted from the couch and displayed on the thermal imaging device.Thermal imaging devices have progressed a lot since their invention, first generation thermal imagers used a glass tube technology and while the images produced were useful, early units were prone to white out where the screen only sees heat because the room and/or the heat source was to hot for the sensors. Second generation of imagers used Ferroelectric detectors also know as Barium Strontium Titanate (BST) detectors. While the image quality has improved over the first generation, the images produced have a visibly slow reaction time so they can be rather choppy, showing dark areas around hot images and the smearing of images during movement of the camera. The third and most advanced generation of imagers use microbolometer imaging technology which creates a high quality image by focussing heat onto an arrangement of microscopic picture elements (pixels) and converting this change in heat into an electrical signal. These signals are processed by the imagers electronics to form an image which is displayed...
