Freeform fabrication is sub-aperture by nature and gives rise to mid-spatial frequency structure. This paper compares methods for quantifying mid-spatial frequencies: power spectral density, autocorrelation function and structure function, and discusses aspects unique to freeforms.
© 2013 OSA
(120.3940) Instrumentation, measurement, and metrology : Metrology
(120.6650) Instrumentation, measurement, and metrology : Surface measurements, figure
(120.6660) Instrumentation, measurement, and metrology : Surface measurements, roughness
A. D. Davies, L. He, and C. J. Evans, "Mid-spatial Frequency Specification and Characterization for Freeform Surfaces," in Renewable Energy and the Environment, OSA Technical Digest (online) (Optical Society of America, 2013), paper FW2B.1.
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