46
It is obviously at the top of testing fiber influence on Pulse width , in below
chart,we cant detect the first connecting point locate in the 540m by large
pulse width.(see Figure 3)
Figure 3
Dynamic range decided by Pulse width,larger pulse width will spend more
optical power,but it reach further.(see Figure 4)
Figure 4
Setting proper wavelength
Proceed test with same fiber but different wavelength we will get different
result. Longer the testing wavelength is,more sensitive of the bending, in below
chart ,first splicing point has bending problem,splicing loss value under
1550nm is bigger than that under 1310nm. the other points are similar with
1310nm and 1550nm.This phenomenon indicate that this fiber is just bended
at the first point. If it's possible please alway compare the point state under
1310nm and 1550nm and judge whether it's bended or squashed.(see Figure
5)
500ns
50ns
5000ns
