Vergleich fraktaler Parameter von Rauheitsmessungen an glatten Oberflächen mit profilometrischen und Streulichtmessungen

Roughness measurements on smooth samples of scattering and profilometric measurements are compared. Scattering measurements lead to the power spectral density of the surface while profilometric measurements lead to the surface profile. Usually from these functions surface roughness parameter were calculated and compared with each other. It is shown, that because of the different spatial frequency bandwidths of these measuring processes this procedure leads to dramatically errors. Another possibility is to describe smooth surfaces as fractals. The fractal parameters are calculated in three different ways and compared with each other.