Apparatus for measuring integrated light scattering of optical components over an extended range of wavelengths

A total integrated scattering (TIS) measurement set-up is described which enables the detection of scattered light within a spatial frequency range from 0.0041 mu m(-1) to 4 mu m(-1). The apparatus is based on a Coblentz sphere and is equipped with light sources in the wavelength range from the UV to IR (248 nm - 10.6 mu m). Exemples are presented of measurements on samples with rms-roughness from angstroms to microns.