Coupling Efficiency and Alignment Sensitivity of Single Mode Optical Fibers

Coupling efficiency an alignment sensitivity models for the coupling of light from a fundamental mode Gaussian light beam into a single mode optical fiber are given. Experimental results are presented which verify the coupling and misalignment predictions of the models. Data were taken at two wavelengths: 0.6328 and 0.8460 micrometers. The light sources were a HeNe laser and a GaAlAs laser respectively. Coupling efficiencies were measured versus beam spot size; and lateral, axial and angular misalignments of the beam and fiber axes