Fiber Port Cluster 1 ⇾ x

These Fiber Port Clusters are compact opto-mechanical units that splits a fiber-coupled source into multiple output fiber cables with high efficiency and variable splitting ratio.

Optical Setup
The input port is fiber-coupled to PM fiber cable. A polarizer defines the input polarization which is necessary for a long term stable splitting ratio.
A photo diode right after the input port allows for a continuous monitoring of the radiation.
Subsequently, the radiation splitting is achieved by using a cascade of rotary half-wave plates in combination with polarization beam splitters. By use of the rotary half-wave plates, almost any desired splitting ratio can be achieved.
At the output ports further polarizers are placed in order to define the polarization at output of the system.

Fiber Couplers
A fundamental component of a Fiber Port Cluster is the Laser Beam Coupler, which is the input into the opto-mechanical unit collimating the input radiation and, finally, couples the radiation back into the polarization-maintaining fiber cables. The stability of the total Fiber Port Cluster is determined by the stability of the laser beam coupler.