The influence of BRDF calibration to CT industry NDT

Computed Tomography (CT) testing is an important non-destructive testing technology in industry inspection. So the important work of CT development is the value calibration and the precise result judgment. Bi-directional reflection distribution function(BRDF) as the common spatial characteristic parameter can be fit for the CT data structure in theory level and the CT data cube can be calibrated using BRDF in both spectral and spatial. Deferent processing calibrated images can be achieved by calibrating CT data in deferent dynamic range using corresponding BRDF absolute value. Thus the influence of BRDF calibration to CT data can be achieved from these serial calibration data and the optimized arithmetic model for this calibration is established. Furthermore, the uncertainty of this value traceability and calibration is analyzed and a corresponding example in CT industry NDT is given which illustrate that this calibration is useful in analysis of PT image because it provide more true image and reduce the probability of error judgment.