The spectral sensitivity of the human eye lies in the range of 400 – 700 nm. But there are also natural and artificial emissions on both sides of this range. While the visible range can be covered by CCD and CMOS cameras, the NIR range of 900 – 1700 nm is covered by InGaAs cameras. An NIR camera with InGaAs detector has a high spectral sensitivity and reaches a quantum efficiency of more than 80%. The NIR camera detector is based on a focal plane array. The setup can be compared to that of the CMOS technology, as the recording pixel is directly connected to the below readout.
Shortwave infrared (SWIR) cameras use MCT (mercury, cadmium, telluride) detectors and cover the range of 850 – 2500 nm. With heated objects, an SWIR camera may be used as thermal imaging camera, but its main applications are the material analysis of objects that absorb or emit in the shortwave infrared.
MID (micro imaging device) cameras are used for radiometric measurements and thermographic analyses in the range of 3 – 5 µm. A cooled InSb camera features high sensitivity and homogeneity over a broad temperature range. It detects even the smallest differences in temperature and still works with short integration times. This is why cooled MID cameras are often used for infrared high-speed imaging.
The range of 8 – 14 µm is in the longwave infrared (LWIR). Our ambient temperature shows a high radiation at 10 µm. This is why LWIR cameras are mostly used as thermal imaging cameras to measure temperatures and temperature distributions. They may also be used for non-quantitative measurements such as the heat distribution during cooling processes.
LWIR cameras often use microbolometers as detectors. A microbolometer camera is uncooled so the detector works in ambient temperature. It is perfectly suited for small and lightweight high-quality IR camera systems.
Some thermal imaging cameras are utilized in the longwave range. They work with cooled HgCdTe detectors. LWIR MCT and QWIP (quantum well infrared photodetector) cameras are mainly used in military research.
No matter what wavelength and frame rate you need, we have the perfect IR camera system to suit your needs.