Method for measuring thickness of magnetic recording medium

摘要

A method for measuring the thickness of a multi-layer magnetic recording medium which provides a high accuracy and which can be used for continuous on-line monitoring of product thickness. First, first and second magnetic layers are simultaneously coated onto a running nonmagnetic support to form the recording medium. The first and second magnetic layers are made of materials having different responses to fluorescent X-rays. Then, the thickness of at least one of said first and second layers is measured by exposing the recording medium to fluorescent X-rays.