Coupling efficiency angular mapping of a collimated interferometric optical head.

A 20-mm focal length collimator is aiming at a plane mirror. This dataset contains the two-axis angle (degrees) of the mirror (two first columns of the dataset) and the coupling efficiency (third column). Coupling efficiency is acquired using a super-luminescent photodiode, an optical isolator, an optical fiber 50/50 coupler, and a photometer. Coupling efficiency is defined as I1/I0, where I0 is the intensity of light retro injected into the fiber due to Fresnel reflection off the fiber end, and I1 is the intensity retro collected into the fiber after reflection off the plane mirror.