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Application Tutorials
Tutorial 3: Measure Extinction Ratios on Low-Level Signals
Autoscaled Display of Low-Level Signal
4 Turn filtering on by pressing:
Setup, eyefltr ON OFF ON
Perform an Offset Calibration
This calibration procedure removes any offset that may be present in the opti-
cal-to-electrical converter. This is sometimes referred to as the "dark" level.
The offset calibration ensures accurate measurements of the laser’s level.
5 Turn the laser off. (If you are measuring the pattern generator directly,
disconnect the input signal at channel 1.)
6 Perform the calibration by pressing:
Trg,Cal, OFFSET CAL, CONT
The calibration takes about a minute to execute. When the calibration is
finished, DC NULL: done is displayed.
7 Turn the laser on. (If you are measuring the pattern generator directly,
reconnect the input signal at channel 1.)