Polytec TMS-350 TopMap In.Line, Руководство по оборудованию

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6-5
6 Technical Specifications
INFORMATION
The sampling increment not only has great influence on the resolution but
also on the measurement time. You have to accept an inferior resolution to
realize a short measurement time. This mean that sample rates < 50 nm only
slightly improve the resolution, but significantly increase the data rate and the
size of the measurement file. Apart from that, it can be said, the shorter the
increment, the smaller the largest possible AOI.
Calculating the Measurement Time
Equation 6.1
The following values for the measurement time result from a z measurement
range of 15 µm and a frame rate of 202 images per second.
Typical step height measurements on a calibrated depth setting standard
1
1
Empirically determined typical performance when measuring a calibrated PTB depth setting standard
type A1 (ISO 5436-118 ), sampling increment "Nominal", measurement speed 18 µm/s.
Nominal groove depth µm 5 50 450
Expanded uncertainty of measurement
2
2 Interval limit of a confidence range with 95.4% probability (2 σ ), determined from the standard deviation
from the calibrated value over all measurements at the respective step height
µm 0.15 0.3 0.35
Relative measurement uncertainty % 3.00 0.60 0.08
Repeatability
3
(standard deviation)
3
Variation of measurement values for a series of measurements under repeatability conditions averaged
over several measuring instruments
µm 0.05 0.05 0.05
Relative repeat precision % 1.00 0.10 0.01
Reproducibility
4
(standard deviation)
4
Variation of measured deviations at on stage respectively for series of measurements under
reproducibility conditions with several measuring instruments
µm 0.05 0.05 0.05
Relative reproducibility % 1.00 0.10 0.01
Sampling increment Measurement time
Nominal ~ 1.2 s (without averaging)
Quick sampling ~ 0.32 s (without averaging)