Recent advances in PLC functional devices

To achieve much larger capacity in point-to-point wavelength division multiplexing (WDM) transmissions, we must increase their bit rate per wavelength as well as their channel number. Optical networks are continuing to adopt rings and packet-switched systems. These advanced optical systems require highly functional optical devices to exceed the electrical speed limit. I describe recent advances in planar lightwave circuit (PLC) based functional devices, such as dispersion equalizers, large-scale arrayed-waveguide gratings (AWGs), and optical signal processing devices.