A new assembly architecture for multichannel singlemode-fiber-pigtail LD/PD modules

A novel assembly architecture is developed for alignment and soldering between single-mode (SM) fiber arrays and laser-diode/photodiode (LD/PD) arrays. The image position detection method, by eliminating degrees of freedom for alignment, improves assembly throughput to twice that of conventional assembly architecture. The thermal shrinkage compensation method achieves high-precision soldering by canceling misalignments due to thermal shrinkage of assembly equipment and solder volume. As a result, assembly, through all processes, achieves ±1.5-μm precision, which corresponds to a ±1-dB fluctuation of coupling efficiency. Based on this architecture, eight-channel SM-fiber-pigtail LD/PD modules were successfully assembled