Thermogram of AC adapters. Shown here is a thermogram of several AC adapters plugged into a power strip. Such power supplies are frequently used to provide DC power to small electric and electronic household appliances. Conventional power supplies use electrical transformers that consume mains power even when no load is connected to them, as is the case in this image. As it can be seen, the consumed power heats up the power supplies. Thermography is a technique for visualizing the temperature of objects by recording the thermal emission intensity at long infrared wavelengths. This image was acquired with a specialized camera that uses a focal-plane array of vanadium oxide microbolometers as a sensor. It is sensitive to electromagnetic radiation in the wavelength range of 8 to 14 micron. The camera produces a 320x240-pixel image where different colors correspond to different temperatures.