The NORMI 13 test object is designed for acceptance tests and constancy tests of X-ray equipment with a digital image intensifier. It includes a structure plate with radiological visible line marks for the light field adjustment and the test of the light field/radiation field congruency, a gray scale test, a low-contrast test, a line group resolution test pattern, an area for entrance dose measurement and homogeneous areas for homogeneity tests and signal normalization. The structure plate is used in combination with a 30 mm thick acrylic attenuation plate or a 25 mm Al plate to simulate patient absorption.
