Veins can give you a blue tint. If your eye areas look particularly blue, it could simply be your blood vessels. Blue veins under your eyes look dark, too, so it makes the eyelids and under eyes appear to have dark circles, but really it's just the veins under the skin, explains Dr. Katz.
Thermal imaging is based on heat. All objects, both natural and manmade, emit infrared energy as heat. This energy is actually part of the upper infrared light spectrum. The energy waves can be collected and focused by the right equipment to create a visible image, even when something is not visible to the naked eye.ithin the IR part of the spectrum, there is a long-wave infrared (LWIR) spectrum. There, objects emit energy even when visible light is not present. Thermal imaging... 1  Can highlight people, animals, and objects. 2  Be used to track fugitives or vehicles. 3  Works in both daylight and darkness. 4  Can see through haze and smoke.
Infrared Energy Detection. An infrared camera is a non-contact device that detects infrared energy (heat) and converts it into an electronic signal, which is then processed to produce a thermal image on a video monitor and perform temperature calculations.