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Application Tutorials
Tutorial 4: Measure Laser Turn-on Delay
Tutorial 4: Measure Laser Turn-on Delay On-screen markers can be used to measure both amplitude and time separa-
tion in eye-diagrams. The compatible modes for markers are eye, eyeli ne, and
pattern.
Change to Eyeline Mode
1Change to eyeline mode, then turn filtering on by pressing:
INSTR PRESET, Setup, diagram, EYELINE, eyefltr ON OFF ON,
BIT INTVL and enter 1
2Set the persistence to infinite by pressing:
Traces, persist, INFINIT, Trg,Cal
3After several traces have been displayed, press:
CONT STOP STOP
Turn on the markers
4Press X1 and X2 to activate markers 1 and 2.
5Turn the front-panel knob to move the markers to different tran sition crossing
points on the waveform as show in the following figure.
This provides an easy method to check the peak-to-peak difference in the laser
turn-on time measured at the crossing point. Notice in the followi ng figure, a
delta reading of 30 ps is displayed at the top of the screen.