OPTICAL COUPLING SYSTEM

摘要

An optical filter is disclosed having a pair of GRIN lenses disposed back to back, and having parallel end faces orthogonal to coaxial optical axes. Optical fibre tubes having optical fibres therein are disposed adjacent the GRIN lenses and have their inwardly facing end faces slant polished to lessen the effects of unwanted back reflections. This arrangement wherein optical axes of the optical fibre tubes are not parallel to the optical axes of the GRIN lenses is novel and inventive.