Thermography is a type of imaging achieved with thermal cameras that are sensitive to parts of the infrared ratiation spectrum.
The intensity of their emitted energy varies with temperature and wavelength and for objects cooler than 500 ℃, the emitted radiation lies completely within the IR wavelengths . Depending on the detector material, the camera is sensitive to a certain part of the electromagnetic spectrum [Fig 1?]. The camera detectors are of two types: thermal detectors and quantum detectors. The main thermal camera used in this research (FLIR A65sc) uses a microbolometer type thermal detector and it is sensitive to the LWIR (long wavelength IR) part of the spectrum.
Detector Types and the IR spectrum ranges where they are sensitive
The FLIR A65sc it an uncooled microbolometer type thermal camera usef for measuring temperatures of solid objects in a non-invasive manner. The main technical specifications of the camera are presented in the table below. The full specifications can be found here: https://www.flir.co.uk/products/a65sc-test-kit/.
|IR resolution||640 x 512 pixels|
|Thermal sensitivity/NETD||<0.05 ℃; @30 ℃/50 mK|
|Field of view||45˚ x 37˚|
|Focal Length||13 mm|
|Image frequency||7.5 Hz|
|Spectral range||7.5 – 13 um|