Number of Points: Select for data resolution over the temperature range selected
Fast and slow axes indices: Sets the birefringence of the fiber
Wavelength: Wavelength in microns
Distance Z between components: This is the length of each fiber linking the couplers. This program runs for a string or chain of couplers; for example 3 couplers with two linking fibers, two pigtails for input /output and two connectors will give results that are typical of each channel of a 1 x 8 array.
The input in the case above would be: con1, cpl1, cpl2, cpl3, con2
This requires: 4 fiber lengths Z values
4 temperature ranges T
5 cross coupling values (dB)
Wavelength change is used for small variations that change phase when z (Temperature range) is set zero. Couplers have a ratio that is wavelength sensitive, but this is negligible for a few Pi phase changes.
The output displays the ER of a string over the temperature ranges selected.
Typical values to enter.
Evanescent Wave Couplers manufactured with “Optical Contact” show a range of ER dependent on wavelength, fiber type, and particular fiber batch and process variables. The typical range is -22dB to -30dB
For 1550nm the peak is flat and ranges from -24dB to -27dB
Z values: are typically 60cm for linking fiber segments, 100cm for input and output pigtails
T ranges are usually less than 5 deg C
Upper line is phase comparison of fast to slow axis light (red).
Lower deeply dipping line is the state of polarization (without reference to the fiber axis)
(violet) and is 10log max/min of the polarization ellipse.
Mid line is ER 10 log fast/slow axis light intensity (turquoise).