OZ Optics’ Polarization Extinction Ratio Meter allows one to quickly measure the output extinction ratio of light from a fiber. A rotating polarizer measures the extinction ratio (ER) and the orientation of the transmission axis with respect to the key on the connector. As an option, neutral density filters can be added to the Extinction Ratio Meter, to extend the maximum power range. These filters can be easily inserted and removed, without disturbing your setup. These filters allow power levels up to 2 Watts to be measured.