Datacom applications for new VCSEL technologies

The advent of the vertical cavity surface-emitting laser (VCSEL) has spurred numerous applications requiring low-cost high performance laser sources. Gigabit Local Area Networks (LAN) utilizing multimode fiber-optic communication systems have predominantly pushed VCSEL technologies to their current state. In order for VCSEL technologies to continue driving the optical networking interconnect solutions, new datacom applications have been proposed. Course Wavelength Division Multiplexing (CWDM) is one such application being proposed that has the potential to significantly increase both the capacity and distance of optical interconnects, while still maintaining a low cost. Designing CWDM (Course Wavelength Division Multiplexing) systems for integration into a small and low cost package suitable for LAN applications has many challenges. These challenges include producing multi-wavelength VCSEL arrays, miniature multiplexers and demultiplexers, passive alignment, and thermal management. The first section of this paper will describe the VCSEL wavelengths and thermal requirements necessary to achieve an 8-channel CWDM system. The second section will describe the optical multiplexer and demultiplexer technologies. The final section will discuss several specific applications and products that VCSEL CWDM systems can address.