Mitutoyo SURFTEST SJ-410 - Page 560

No. 99MBB765A
23-10
• GAUSS
The amplitude characteristic is approximately -11.6 dB/oct, and the amplitude
transmission at the cut-off value is 50%. The attenuation characteristic is shown in the
figure below.
Attenuation characteristic of the GAUSS (Gaussian) filter
Attenuation characteristic:
(
)
2
1






−
−=
λ
λ
π
λ
ca
e
H
where
0.4697
2
ln
2
1
≒






=
π
a
Using this filter results in a simple equation:
unfiltered profile = roughness profile + waviness profile
Therefore, the low-pass filter is characterized by:
Attenuation characteristic:
(
)
2






−
=
λ
λ
π
λ
ca
eH
.
Amplitude transmission (%)
Amplitude transmission (dB)