Coupling efficiency of optics in single-mode fiber components

Many single-mode fiber components include some form of optics, such as lenses or mirrors, for collecting light from a source fiber or laser and concentrating it on a receiving fiber. For such components there is a direct and simple relationship between coupling efficiency and optical aberrations. This paper combines fiber-coupling fundamentals, classical optics, and diffraction theory to provide a compact description of coupling efficiency that includes the effects of aberrations, fiber misalignments, and fiber-mode mismatch.