Presentations

Currently, board-level optical interconnection is anticipated as a promising technology to realize high-performance computing systems with high speed and low-power consumption. Hence, optical printed circuit boards (OPCBs) integrated with polymer optical waveguides are drawing much attention, in particular, intensive efforts have been made for developing crossed waveguides for solving the problem of the space limit on OPCBs. In general, those crossed waveguides have been composed of step index (SI) type core. However, the excess optical loss at the crossed area due to the light leakage has been crucial. In this paper, we propose to apply graded-index (GI) cores to such a crossed waveguide. We already confirmed the strong optical confinement effect of GI core, thus it is expected that GI core enables to decrease the light leakage at the crossed area, compared to the SI-core crossed waveguides. In fact, we calculate the light propagation loss in crossed waveguides with SI and GI cores by developing a ray tracing simulation program. It is found that GI core shows remarkably lower waveguide loss (0.19 dB for 50-perpendicular crosses) than those of SI core (3.7 dB).

Optical interconnect has been highly anticipated as a promising technology to realize high-performance computing systems (HPCs) with high-speed and low-power-consumption. For the data transmission between boards and between racks in current HPCs, multimode optical fiber (MMF) based links have been already installed. The next technical issue is how to realize on-board optical interconnects, by which high-speed optical signals are distributed closer to the processing chips on-board. In this paper, we focus on polymer optical waveguide based links for on-board interconnects, and discuss their link power budget in order to support a data rate of 20 Gb/s and beyond. Specifically, we demonstrate that GI-core polymer waveguides we have been promoting exhibit a link power budget advantage of 3 dB and higher compared to conventional SI-core polymer waveguides.

GI型POFの伝送帯域とリンクパワーペナルティーに関して解析した結果、500Mb/s程度の光リンクにおいてもギガヘルツオーダーの伝送帯域を有するGI型POFを用いれば、パワーペナルティーを０dBとすることが可能であり極めてリンクの設計の自由度が得られることを報告した。

近年，期待が高まってきている情報家電機器間の高速ネットワーク，ならびに高速オフィス，キャンパスLANなどの通信メディアとして期待が寄せられているGI型POFの伝送損失特性，信頼性，伝送帯域特性および，応用展開に関する近年の動向について報告した招待講演．