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In the Rough



Theodore V. Vorburger, Joseph Fu, N G. Orji


Surface roughness affects the function of a wide variety of engineering components, including airport runways, highways, ship hulls and mechanical parts. Perhaps the most demanding applications are in the optics and semiconductor industries. Surface roughness causes scattering and stray light in optical systems and degrades the contrast and sharpness of optical images, so in general, the smoother the surface, the better the component will function. In the optics industry, the terms surface roughness and surface finish are synonymous. The rms roughness is perhaps the most widely used parameter for specification of the roughness of optical surfaces. For high-performance optics, such as those in lithographic steppers, space optics, and laser gyro systems the rms roughness is specified in the subnanometer range. If the measured surface topography is represented as a surface profile z(x), the rms roughness (Rq) is defined as the root mean square of the deviations of the surface profile z(x) from the mean line.
Optical Engineering Magazine
No. 3


atomic force microscopy, interferometry, nomarski, power spectral density, profiling, rms, roughness, stylus, surface


Vorburger, T. , Fu, J. and Orji, N. (2002), In the Rough, Optical Engineering Magazine (Accessed April 20, 2024)
Created February 28, 2002, Updated October 12, 2021