Prediction of optical variations in paper from high resolution measurements of paper properties

A method to predict optical variations from high resolution measurementsof paper properties is evaluated in this work. The method combines thepoint-wise values of high resolution maps of filler content and grammagewith an empirical model derived in an earlier study to predict thespatial optical variations in paper.The method has been applied on two paper samples, a laboratory paper anda commercial 80 g/m(2) copy paper. The optical variations have beenpredicted at a scale of 1 mm(2). Validation has been made by using ahigh resolution spectrophotometric setup to measure the spatialreflectance variations in the paper. The results show that for thesamples used, the influence of filler content variations and densityvariations on the optical variations is small compared to influence ofthe grammage variations.