PV峰谷值 RMS整个面型峰谷的均方根 PWR 光圈 IRR 面型不规则度
PV (Peak-to-Valley) is the distance
between the highest and lowest points
within the sample.
RMS
Root-Mean-Square or rms is the root-meansquare
deviation from the center line. This is a
method of calculating an average by squaring
each value and then taking the square root of the
mean.
IRR
Irregularity (IRR) is the tolerance of the surface form error which remains after the
sagitta error is removed. It is the PV with respect to the best fit reference sphere. Part of
the ISO figure specification (ISO 10110-5).
