Abstract

PLC technology can be used to fabricate several key components for use in Passive Optical Networks (PONs). The key building blocks for PONs include broadband optical power splitters for signal distribution and video combiners to support the BPON type video overlay function. Unlike components fabricated from fused biconic tapers (FBT) and thin film filters (TFF), PLCs can integrate multiple functions onto a single chip to significantly improve performance and cost savings.A broadband 2x2 splitter is a critical component for PON. A directional coupler and even a single stage Mach-Zehnder is unsuitable for this application because each provides a splitting ratio that has excessive wavelength dependence. We demonstrate a PLC-based, broadband 2x2 splitter constructed from a two-stage lattice filter that has low loss and high uniformity from 1260 nm to 1625 nm.Y-branch splitters can be cascaded to make 1xN splitters or integrated with a 2x2 splitter to make 2xN splitters. We compare insertion loss and uniformity for splitters that are fabricated with silica on silicon technology versus silica on quartz technology. By using silica on quartz technology, we demonstrate low-loss 1x32 splitters. The 2x32 splitter has increased functionality with negligible loss penalty. We demonstrate that PLC-based splitters satisfy all reliability requirements.A WDM/splitter can be used for video overlay onto a bidirectional, digital, fiber optic communication system. The video overlay uses 1550nm light, while the digital communication system either uses 1310nm light in both directions or uses 1310nm light for one direction and 1490nm light in the other direction. The video signal is split N times and coupled into N bidirectional digital channels with a biplexer for each channel. With PLC technology, the biplexer is based on integrated Mach-Zehnders. We demonstrate a 32 channel WDM/splitter designed for digital channels using 1310nm light. We also demonstrate a 4 channel and an 8 channel WDM/splitter designed for digital channels using both 1310nm light and 1490nm light.

© 2006 Optical Society of America

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