EXFO PSO-100 Series Optical Sampling Oscilloscopes - Manual (Page 70)

Setting up and Using the Optical Sampling Oscilloscope
62 PSO-100
Using the Eyeline Mode
2. In the Display menu, select Eyeline mode.
The figure below shows an eyeline trace from a normal 40 Gb/s, NRZ 127,
bit pattern. Before the eyeline trace appears all bins (separated with 1 ps)
must be filled with at least one sample. During this process, the maximum
number of samples in any bin, the average number of samples per bin, and
the minimum number of samples in any bin are shown in the sample
window. This will be noticed first when the pattern is relatively long.