INFICON STM-2XM 2-Channel Rate/Thickness Monitor - Manual (Page 55)

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STM-2XM Operating Manual
3.3.3 Averaging
The averaging mode is spatial averaging for two sensors. STM-2XM calculates
weighted averages of two sensors to determine the film rate and thickness. Both
sensors must be active and monitored at the same time. The effective
rate/ thickness is the average of the readings between Sensor 1 and Sensor 2.
NOTE: Averaging mode requires two operational sensors.
Figure 3-11 Averaging mode
Source Source
Substrate
Substrate Shutter
Sensor Shutter
Sensor
Chamber
Shutter
Notice that both sensors are on
and their shutters are open.