METHOD FOR MEASURING THICKNESS PROFILE OF MATERIAL

摘要

PROBLEM TO BE SOLVED: To provide a method for obtaining thickness of a moving material having at least two optical interfaces. SOLUTION: A long material is conveyed along a conveying path through a measurement region and maintained at practically constant velocity and specific flatness. A light beam is cast on the moving material arranged in the measurement region. A part of light reflected from an optical interface the moving material is condensed and forwarded to an interferometer device 20. The interferometer device 20 produces interference signal indicating the condensed light. By analyzing a plurality of interference signal, the thickness profile of the material in the first direction is obtained.