Mitutoyo SJ-210 - Rδq (ISO1997, JIS2001, ANSI, VDA, Free): Mean Square Slope (Angle of the Mean Square Slope); Lr (Free): Expansion Length Ratio; Mr (JIS2001, ISO1997, ANSI, VDA, Free): Material-Ratio-Length Rate

18. Reference Information
No.99MBB122A
18-31
18.5.19 RΔq (ISO1997, JIS2001, ANSI, VDA, Free): Mean square slope (angle of the
mean square slope)
Δq is the square root of the arithmetic mean of the squares of the local slope (dz/dx) of the
evaluation profile.
2
1
1









n
i
dX
dZi
n
qR
 For ANSI, RΔq is defined over the entire evaluation length.
18.5.20 lr (Free): Expansion length ratio
Ir is the ratio of the expansion length (Lo) and the sampling length (l), and this ratio
describes the degree of depression in the evaluation profile. (Expansion length ratio)
l
Lo
lr 
18.5.21 mr (JIS2001, ISO1997, ANSI, VDA, Free): Material-ratio-length rate
Let a slice line whose mr[c] value falls between 0% and 99% (in 1% increments) be the
reference line, and provide more slice lines at constant increments (in m) below the
reference line. mr[c] values at each slice level are referred to as mr values.
Material-ratio-length rate, mr
There are the following 3 modes for specifying slice lines.
Normal Length (μm)
Rz Percentage of Rz
(%)
Rt Percentage of Rt
(%)
Reference mr[c] value (%)
mr[c] value (%)
DEPTH
(

m
)
C
i
Reference line
mrci