Method for characterization of a surface topography

A method for characterization of a surface topography, comprising at least application of the following steps:

• measurement of the surface topography;
• first fitting of data output from the measurement of the surface topography, made from an order m first equation;
• filter data output from application of the first fitting, eliminating some of the data output from application of the first fitting the values of which are greater than a maximum value or less than a minimum value;
• determine the data fitting coefficients for data output from the application of filtering, from an order n second equation;
• second fitting of data output from application of the first fitting, made from the order n second equation and coefficients determined by application of the previous determination step;
• n and m being positive integers greater than or equal to 1 and such that n≧m.