Reduction of fiber alignment shifts in high-speed laser module packaging

The post-weld-shift (PWS) induced fiber alignment shifts of fiber ferrule-clip (FFC) joints in high-speed butterfly laser packaging by laser welding technique has been studied experimentally and numerically. There are two types of clip design in the FFC joint: the type I design is without a gap between clip and fiber ferrule and type II is a 5 μm gap. Using a novel 230× high magnification video probe camera with image acquisition system, the measured results showed that the fiber shifts of FFC joints with the type II exhibited shifts less than that with the type I. The experimental measurements of fiber shifts were in reasonable agreement with the numerical calculations of the finite-element method (FEM) analysis. This study has demonstrated that the FEM is an effective method for predicting PWS induced fiber alignment shifts in laser module packaging.