The thickness gauge, as one of the applications, has succeeded in thickness measuring of the different materials in large range, and present a new application field for characteristic X-ray source.

This paper gives a detailed introduction about our developing and designing process for X-ray thickness gauge using in biaxial oriented polypropylene (BOPP) film.

For this reason, we develop a model which can calculate thickness for plate rolling, and an X-ray thickness gauge monitor and several compensation algorithms are used to compensate model error.