A surface mount single-mode laser module using passive alignment

A novel single-mode laser module has been developed using a surface mounting technique. A simple receptacle structure for the module output port is also designed. This module offers high coupling efficiency and optical coupling using the passive alignment technique. A module size of 7.6 mm/spl times/12 mm/spl times/3 mm is achieved, which is very friendly for the automatic assembly line as well as the module mounting process on circuit boards. A laser diode (LD) is passively positioned by utilizing a pair of alignment marks, each of which located on the LD and Si substrate, a single-mode fiber with a microhemispherical lens on the fiber facet is self-aligned on a Si-V groove. The LD to single-mode fiber coupling loss and standard deviation are found to be 5 dB and 1.5 db, respectively. The simple receptacle structure enables one to use this module in the same way as conventional surface mount electrical components. The module assembly process is simplified by successively mounting subassembly parts.