Optical sensors are designed usually for microscopic or for macroscopic app
lications. White-light interferometry on the other hand enables high-resolu
tion measurements to be made for small and for large fields. In this paper
we present a flexible set-up that can be used for both microscopic and macr
oscopic applications. The magnification can easily be changed in seconds an
d the zoom range is greater than 160. This set-up is especially designed fo
r the investigation of optically rough surfaces. A novel filtering techniqu
e enables fast and accurate data acquisition and evaluation with standard h
ardware components. Further we demonstrate results of roughness measurement
s in different scales.