4 channel × 10 Gbit/s optical module for CWDM links

For CWDM applications, we have developed a new compact low-cost optical module that has four different colored 10-Gbit/s transmission channels and a total throughput of 40-Gbit/s. The target applications of the module are the links between network nodes, such as routers that handles 40-Gbit/s traffic, and access networks using the WDM-PON system. 40-Gbit/s laser modulators, PDs and driver LSIs are available, but are still expensive at the present time. However, a 10-Gbit/s optical link can be achieved by using cheap direct-modulation LDs and low-cost CMOS driver LSIs. Thus, a four-channel CWDM link is the most cost-effective way to achieve 40-Gbit/s transmission. The module we have developed has a compact package size of 30 mm×33 mm×6.3 mm, and is assembled with simple optical alignment process to reduce the assembly cost. We confirmed CWDM transmission over a 10-km fiber with a pair of commercial available CWDM MUX and DEMUX filters.