CALIBRATION PROCEDURE FOR FOCAL-PLANE ARRAY CAMERAS AND NOISE EQUIVALENT MATERIAL LOSS FOR QUANTITATIVE THERMOGRAPHIC NDT

In this paper a complete procedure is proposed for the calibration of a focal plane array in quantitative infrared nondestructive testing (N DT). This procedure includes vignetting correction and gray level conv ersion into temperature. A noise analysis is also presented in the con text of pulsed infrared thermography applied to NDT. In this analysis, we introduce a new parameter the noise equivalent material loss (NEML ). The NEML is a global figure of merit which allows the comparison of different experimental set-tips for infrared pulsed thermography. The ory, experimental validation of the proposed concepts, and comparison with a few infrared scanning thermal imagers are presented as well.