Method for contact-less determination of thickness of fiber web e.g. newspaper web, involves deriving value that is determined by optical sensor for correction of thickness value that is determined by optical thickness sensor

摘要

The method involves using an optical sensor arrangement, which comprises an optical sensor in addition to an optical thickness sensor, which determines a surface structure of the optical sensor. The optical thickness sensor is used to derive a value that is determined by the optical sensor for correction of a thickness value that is determined by the optical thickness sensor. The optical sensor is designed as a luminance sensor and a roughness sensor, where the optical sensor comprises a light source (12), and a material web (10) is subjected to light by the light source.