Optical add/drop devices employing waveguide grating-based wavelength selective switches

摘要

This invention relates to optical add/drop devices. These optical add/drop devices are all based on waveguide grating-based wavelength selective switches. Four types of optical switches (S-, L-. X-, and O-type) are disclosed and used to build optical add/drop devices. In addition to the universal advantage of requiring no multiplexers and demultiplexers, each type of switches has its own advantages to build add/drop devices. A simple add/drop device can be made by using only two switches. A large-scale add/drop device can also be built upon same switches. Since the switches are integrated and fabricated on a silicon-based substrate, the size and cost of the add/drop devices are also significantly reduced.