As the measurements on the last page show, the polarization state (SOP) of the loop does not change randomly. All SOPs typically lie more or less on a surface going through the Poincaré sphere.
This deterministic behavior can only be overcome by actively scrambling the SOP inside the loop (see figure). Our N7785B is a polarization controller based on LiNbO3 technology. The instrument is capable of quickly switching the SOP within 10µs. Switching can be synchronized by an external signal enabling loop-synchronous operation.
- Random scrambling operation at various speeds
- Pseudo-random scrambling operation for repeated measurements
- 10µs switching time between SOPs.
- TTL trigger inputs for loop-synchronization.