Definition: IR detector

(InfraRed detector) A sensing device that picks up radiation in the infrared band. Used extensively for still and video night vision cameras, cooled IR detectors can sense the makeup of nebulae light years in the distance. IR detectors are expected for many applications beyond night vision, including irregularities in machinery, ice on aircraft wings and faults in circuit boards.

Infrared detection works because most everything in our known world gives off heat, which emits radiation in the infrared band. The first IR detector actually dates back to 1800 when prisms were used to detect this band. By 1900, objects could be detected as far as a quarter mile in the distance. See infrared, IR remote control and IrDA.

IR Sensing in a Digital Camera

In 2001, Sony introduced the F707, its first digital camera with infrared sensing. The viewfinder at top uses the light in the room, while the bottom image shows the view with "Night Framing" turned on.