The quality evaluation device of the judgment aspect of the paper and the quality evaluation manner null which uses

摘要

PROBLEM TO BE SOLVED: To provide a quality evaluator as to a section of paper for detecting the existence of minute foreign matter on the section independently of the existence of disturbance factors such as the layer-built state of a paper pile or an imaging environment to acquire a highly reliable evaluation result, and a quality evaluation method using the same.;SOLUTION: This quality evaluator comprises an imaging device 10 installed opposite to the section 50a of the paper pile 50, a lighting system 20 arranged so that the optical axis A₂₀ of illuminating light makes 60° to 90° with the optical axis A₁₀ of the imaging device 10, a quality evaluation value preparation means 30, and an evaluation means 40. The preparation means 30 comprises a contrast evaluation value calculation means 36 for preparing a cooccurrence matrix concerning the density of each of pixels constituting an image on the section 50a acquired through the imaging of the imaging device 10 to find a contrast evaluation value within an evaluation object scope from the cooccurrence matrix. The evaluation means 40 is for evaluating whether or not the found contrast evaluation value is lower than a previously set reference value.;COPYRIGHT: (C)2009,JPO&INPIT