Parallel free-space optical interconnect based on arrays of vertical-cavity lasers and detectors with monolithic microlenses

摘要

We investigate the use of low-threshold 980-nm vertical-cavity surface-emitting lasers for free-space optical interconnects. The vertical-cavity surface-emitting lasers and backilluminated detectors are monolithically integrated with microlenses on the back sides of the growth substrates to eliminate the necessity of external optics. With a channel pitch of 250 mu m, an interconnect length between boards of the order of 5 to 10 mm with a +/- 50-mu m lateral alignment tolerance can be achieved without external relay optics. The complete link is modeled to predict the system's efficiency and maximum bit rate. Data transmission at 500 Mbits/s per channel is demonstrated. The data rate was limited by parasitics, not the inherent bandwidth of the laser diodes. (C) 1998 Optical Society of America. [References: 17]