Determination of paper formation by Fourier analysis of light transmissionimages

Formation is the measure of variations due to non-uniform fibre distributio n in a sheet of paper. Paper formation is one of the most important propert ies of paper and is still difficult to measure. A method for determining th is property has been developed. This method, based on light transmission im age analysis, uses features of the power spectrum obtained from the Fourier transform to analyse and discriminate between different flee distributions within an image of paper. The method was tested for various furnishes and showed better discrimination between different qualities of formation than the standard formation index.