infraredcameras

Infrared cameras are imaging devices that detect infrared radiation emitted by objects to form pictures that reveal temperature patterns. They operate primarily in the thermal infrared range, roughly 3 to 14 micrometers, though some cameras also cover near-infrared bands for different applications. The resulting images, often called thermograms, display heat differences as colors or shades, enabling visualization of temperature distributions even in total darkness.

Most modern infrared cameras use uncooled microbolometer focal plane arrays, which detect infrared radiation without cryogenic cooling and convert it into electrical signals that produce a visual image. Higher-sensitivity systems use cooled detectors, such as materials like indium antimonide (InSb) or mercury cadmium telluride (HgCdTe), which require cooling to cryogenic temperatures but offer superior sensitivity and faster response. Many cameras can be calibrated to show temperature values on the image, assuming surface emissivity is known and atmospheric conditions are accounted for.

Spectral bands commonly encountered include long-wave infrared (LWIR, about 8–14 micrometers), mid-wave infrared (MWIR, about 3–5 micrometers), and short-wave infrared (SWIR, about 1–3 micrometers). Each band has different transmission properties, detector technologies, and use cases. Infrared cameras record emitted radiation; some systems also utilize reflected near-infrared light, but thermal imaging primarily relies on emitted heat.

Applications are diverse: building and electrical inspections, predictive maintenance, firefighting, industrial process monitoring, medical and veterinary thermography, security and surveillance, automotive night vision, and certain astronomical and research contexts. Advantages include non-contact temperature assessment and operation in darkness or obscured environments, while limitations involve lower spatial resolution than visible cameras, sensitivity to emissivity and weather, and higher cost for high-performance models.