Abstract: The present invention discloses methods and apparatus for constructing optical switch systems, in which any input optical signals can be routed to any output ports. The methods and apparatus provide advantages of configuration flexibility, modular construction, constant signal loss, and minimal numbers of switch units required. The switch systems comprise M×N switch modules. The switch module in turn comprises a two-dimensional waveguide array and a number of waveguide grating-based wavelength selective switches. With the capability of wavelength-selective routing provided by the switch modules, the optical switch systems requires a relatively small amount of switch units to extend into a very-large-scale switch system.

Abstract: The present invention discloses a drop-before-add optical routing and switching system. The drop-before-add optical routing and switching system includes an input waveguide for carrying a multiplexed optical signal comprising optical signals transmitted over a plurality of wavelength channels represented by ?1, ?2, ?3, . . . , ?N?1 and ?N, where N is a positive integer wherein the input waveguide extending over a first direction. The drop-before-add optical routing and switching system further includes a plurality of second direction waveguides extending over a second direction and intersecting at N intersections with the input waveguide. The drop-before-add optical routing and switching system further includes a plurality of wavelength selective grating switches each disposed on one of the N intersections for selectively transmitting an optical signal of a selected wavelength into an associated one of the second direction waveguide.

Abstract: A wavelength selective light source is disclosed. The wavelength selective light source comprises a broadband light source producing light having a plurality of wavelengths and a demultiplexer that receives the light and separates at least one of the plurality of wavelengths from said light. Further, a multiplexer is included for coupling the at least one of said plurality of wavelengths into an output waveguide. Finally, a semiconductor optical amplifier is provided that receives the at least one of the plurality of wavelengths from the output waveguide and amplifies the at least one of the plurality of wavelengths.

Abstract: An all-optical switch with wavelength conversion is disclosed. The optical switch comprises an input waveguide for carrying a multiplexed optical signal comprised of a plurality of wavelength channels. Further included is a demultiplexer for separating the multiplexed optical signal into the plurality of wavelength channels. The wavelength channels are then provided to a wavelength converter operative to convert the wavelength channels into a converted wavelength channel. The converted wavelength channels are input to a switch operative to switch the converted wavelength channels onto output waveguides.

Abstract: A wavelength converter is disclosed. The converter comprises a broadband light source producing light having a plurality of wavelengths. Further, a semiconductor optical amplifier is provided that receives the light from the light source. The semiconductor optical amplifier amplifies the light under the control of a control signal related to an optical signal of a first wavelength. Next, a demultiplexer receives the output of the semiconductor optical amplifier and extracts from the amplified optical signal at least one of the plurality of wavelengths.