infrared sensor

An infrared sensor is a device that detects infrared radiation, which is a part of the electromagnetic spectrum invisible to the human eye but detectable as warmth. These sensors are sensitive to heat signatures, allowing them to identify hot spots like vehicle engines or missile exhausts, even without registering false targets like sun reflections.1

Infrared radiation falls between visible light and microwaves, with wavelengths typically ranging from about 0.78 to 1,000 micrometres. Objects at room temperature emit enough infrared energy to be detected from several miles away, making infrared imagery useful for longer ranges than image intensifiers and capable of operating without starlight. However, high humidity can reduce their effective range.21

Infrared sensors are employed in various applications, including warning systems, revealing hidden objects through camouflage, and in astronomical observations to see through interstellar dust. They are also used in thermography to detect pathological tissue growths and in identifying defects in electronic systems due to increased heat emission.13