Triple Wavelength Demultiplexers for Low-Cost Optical Triplexer Transceivers

We report triple wavelength demultiplexers adopting a thin-film filter (TFF) and a waveguide Bragg grating as a reflector for low-cost integrated optical triplexer transceivers deployed for the triple play service-based fiber-to-the-home (FTTH) networks. In the proposed demultiplexers, 1310- and 1550-nm lights were designed to be divided after passing the planar lightwave circuit-based directional coupler by half-cycle and full-cycle coupling actions, respectively. The 1490-nm light was reflected by a TFF or Bragg grating. The losses of the demultiplexers were less than 2.0 dB at all ports. The average crosstalk among the three lights for the demultiplexers was about -20 dB or better. Through a single reflector, the demultiplexer structures are significantly simplified, and cost is reduced. The proposed triple wavelength demultiplexers provide cost-effective and high-performance solutions for FTTH network systems