Abstract:
Scattering of light from a surface depends on its microroughness. In general, total
integrated scattering of a surface is expressed in terms of root-mean-square microroughness
(σrms) using empirical relations. These empirical relations assume that the σrms is measured over
the spatial scales ranging from 0 to surface length/diameter (L). In reality, σrms will be measured
over finite spatial lengths/scales that result in band-limited microroughness (σbl) and hence bandlimited integrated scatter (BLIS). BLIS depends on the microroughness of surface over the finite
spatial bandwidths rather than infinite spatial scales. Scatter from super polished optical mirrors
peaks in specular direction and falls off exponentially. Hence, BLIS measurements in nearspecular direction provide crucial information in understanding the relation between surface
microroughness and scatter. Our work gives a detailed description of BLIS measurements carried
out on super polished optical surfaces with different surface microroughness and a comparison
between the scatter and surface microroughness measurements.
