The method is self-aligning, avoids fundamental splitting losses, and uses only local feedback loops on controllable beam splitters and phase shifters. It could be implemented with Mach-Zehnder interferometers in planar optics. The method extended to multiple simultaneous mode. In optical communication, a reconfigurable optical add-drop multiplexer (ROADM) is a form of optical add-drop multiplexer that adds the ability to remotely switch traffic from a wavelength-division multiplexing (WDM) system at the wavelength layer. With the assistance of the subwavelength grating structures, the launched modes are redistributed to be the. Agiltron reconfigurable Add/Drop Multiplexer (ROADM) is designed dynamically reconfigurable switching and routing applications in next generation optical communications networks. Optical switching systems in accordance with the present disclosure include arrangements of frequency-filter blocks, each of which includes a cascaded arrangement of tunable.
