Single point calibrations of the imager’s pixels
Thermal imagers are able to produce very high thermal sensitivity images, but our expertise ensures reliable and repeatable temperature measurement. Thermal imaging systems can be calibrated at NPL using conventional radiation thermometry blackbody sources, which cover the field of view of the imager. These give single point calibrations of the pixels.
When in use, though, the field of view can be filled with many different objects and surfaces, which can have a wide range of thermal properties. For reliable and repeatable interpretation of temperature information, the images need to be taken and interpreted very carefully.
NPL has extensive experience in the use and verification of active and passive thermal imaging systems for a wide range of practical applications such as medical diagnostics, low temperature quantitative spacecraft testing, in process monitoring (including food and materials), defence applications (such as combustion) and calibration/validation systems.
We can carry out real-time thermal measurements of processes and systems, and assist with equipment specification, implementation of measurement good practice, validation of techniques and calibration of instruments.
The range of calibration is identical to that for radiator thermometers, and is therefore -40 °C to +1000 °C, and even up to +3000 °C. The uncertainty would be determined by the performance of the imaging system at the time of test, but could be as low as ±0.2 °C.