A Method of Inspecting Non-woven Basis Weight Using the Exponential Law of Absorption and Image Processing

Abstract

This article explores a method of inspecting the non-woven basis weight on-line, by combining the exponential law of absorption and image processing technique. In the experiment, a theoretic equation for the charge-coupled device image-capture transmittance and non-woven basis weight was acquired through the exponential law of absorption. By using light source compensation and the least-squares approximation, the best approximate equations of transmittance and basis weight were acquired. According to the experimental results, the method of inspecting non-woven basis weight by image processing as proposed in this paper can reduce the uniformity of image gray scale from a coefficient of variation (C.V.) of 5.5 to 0.7%, raise the R ² of basis weight and transmittance to 0.998, and decrease the basis weight inspection error to 0.33%. The proposed method effectively enhances the accuracy and stability of non-contact inspection of non-woven basis weight. The result acquired herein can also be applied to the on-line uniformity inspection system with web as the basic material.