The Measurement of Card Web Transparency and its Unevenness

This paper describes an electronic apparatus suitable for finding the mean optical density of the card web and for measuring the unevenness of that optical density. A little more than 1 min is needed to obtain both measurements by means of an integrator, and at the same time a recording instrument traces the corresponding irregularity. Some industrial card webs have been studied, and the practical importance in industry of the optical density and mean linear deviation of these webs is assessed. The curve of variance vs scanning surface seems to be of practical utility in the analysis of card web irregularity.