Winterthur Instruments AG CoatMaster, Руководство пользователя

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Operation Manual CoatMaster
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SNR:
> 20%: not okay, position the optic closer to the sample, increase the light energy; if both measures
do not help, use an optical reflex amplifier.
The calibration report might sometimes show a systematic deviation of the reference values and the
CoatMaster values for the coating thickness. This can be seen by the fact that for thin coatings all
calibration points are located below the calibration line while for thick coatings all calibration points
are above. It can also be vice-­‐versa (thin are above, thick are below).
The following example illustrates this fact:
Although the mean deviation is slightly below the 25 % limit, a systematic deviation of the coating
thickness value of reference and CoatMaster is evident. In this case it is appropriate to allow the
offset for this application. For this purpose select Back twice to get back to the frist side, activate the
option Allow offset and select Next twice.
The calibration report now shows a good correlation of the two measurement methods with a little
mean deviation.