Rhopoint Optimap PSD Operating Instructions Manual page 23

As an overall rating, Total curvature (K), is used to represent the SD (sigma) of
curvatures falling within the range 0.1 – 30.0mm. As a totally flat surface would have
no variation in curvature, higher curvature values indicate that there are more
structures present on the surface at that particular wavelength range.
regular equations are then applied to the filtered curvature data to produce a texture
(T) scaling.
For this scale total texture (T), is used to represent the SD (sigma) of surface
textures with the 7 additional texture bands Ta – Te, TS - TL used to represent the
SD (sigma) of correlated surface textures Wa – We, WS – WL.
This correlation provides a best fit translation from the dimensionless, single or
multiple scan waviness scale to a dimensioned, full field, texture scale
Value Wavelength
Ka 0.1 – 0.3mm
Kb 0.3 – 1.0mm
Kc 1.0 – 3.0mm
Kd 3.0 – 10mm
Ke 10 – 30mm
To correlate to the industry
accepted Waviness scale
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