The Filmetrics ellipsometer accommodates sample sizes ranging few mm-sized piece parts to 4” wafers. The system operates over the wavelength range 380 – 1050 nm, subranges can be set in software. In the beginning of each measurement the spectrum is calibrated using one of the provided standards. One can choose between BK7 (borosilicate glass), Si with a SiO2 layer, and a Si standard. Ideally one picks something similar to the sample to measure. A common measurement is the thickness of a resist film on a sample, e.g. 200 nm PMMA on Si.