Improved optical network configurations are described incorporating ROADM component structures that are compatible with simplified user transceivers. The ROADM component structures generally include a reconfigurable optical add/drop multiplexer component comprising a multicast switch (MCS), a tunable optical filter (TOF), optical amplifiers, and user side ports. The MCS can be connected to network side optical conduits, while the TOF can be connected by optical conduits to the MCS and to the optical amplifiers by a distinct optical port of the TOF. The user side ports can be connected to the optical amplifiers and to light conduits of a user transceiver. In some embodiments, the MCS and the TOF can be planar optical circuits, and the optical amplifiers can be configured for single wavelength amplification. The improved ROADM component structures can be used for add-side components, drop-side components, or bothand provide for energy efficiency and/or improved device layout.

Example embodiments of the present invention relate to a software programmable reconfigurable optical add drop multiplexer (ROADM) comprising of a plurality of wavelength switches and a plurality of waveguide switches, wherein when the plurality of waveguide switches are set to a first switch configuration, the software programmable ROADM provides n degrees of an n-degree optical node, and wherein when the waveguide switches are set to a second switch configuration, the software programmable ROADM provides k degrees of an m-degree optical node.

A method for noise suppression in a colorless optical add/drop system implemented prior to a colorless optical add/drop device includes, subsequent to receiving an optical signal from an optical modem, filtering the optical signal with a wavelength blocking filter to suppress out of band Amplified Stimulated Emission (ASE) in order to prevent noise funneling in the colorless optical add/drop device; and providing the filtered optical signal with the out of band ASE suppressed therein to a multiplexer port in the colorless optical add/drop device. The method can include, prior to the filtering, amplifying the optical signal with a single channel amplifier, wherein the single channel amplifier can include a pump laser shared with one or more additional single channel amplifiers.

A device and method for controlling light by wavelength in a device with a switch plane and a dispersion plane uses optics providing an imaging function in the dispersion plane, and a Fourier transform function in the switch plane, so as to enable crosstalk to be reduced.

An optical switch (10) comprising: input ports (12, 14) arranged to receive optical signals from directions D1 to Dn; output ports (16, 18) arranged to output optical signals to the said directions; drop ports (20); add ports (22); a first switch array (24) arranged to receive from a first said input port (12) optical signals at a plurality of wavelengths, and comprising switch elements (26) each arranged to selectively direct optical signals to a respective drop port. The optical switch (10) further comprising optical filters (28), each arranged to receive from the first input port optical signals having bypass wavelengths, each optical filter arranged to transmit to a respective one of the output ports (18) optical signals at different bypass wavelengths; and a second switch array (30) arranged to receive from the other input ports (14) optical signals at some of said wavelengths, the second switch array comprising a plurality of switch elements (32) arranged to selectively add optical signals received from the add ports at others of said wavelengths.

An apparatus includes a first and second VCSEL, each with an integrated lens. The VCSELs emit a first light beam having first optical modes at first wavelengths and a second light beam having second optical modes at second wavelengths. The apparatus also has an optical block with a first and second surface, a mirror coupled to the second surface, and a wavelength-selective filter coupled to the first surface. The first integrated lens mode matches the first beam to the optical block, and the second integrated lens mode matches the second beam to the optical block such that the first beam and second beam each have substantially a beam waist with a beam waist dimension at the first and second input region, respectively. An exit beam that includes light from the first beam and the second beam is output from the second surface of the optical block.

Methods and systems for intra data center optical switching of optical signals use an intra data center optical switch to optically transmit N optical wavelengths as an optical signal transmitting a data stream generated by a data center system included within N data center systems. The data center system may selectively receive one of N?1 optical wavelengths as another optical signal corresponding to one of N?1 other data center systems excluding the data center system from the intra data center optical switch. In this manner, intra data center optical switching may be performed without utilizing Ethernet and optical switches, which may result in reduced power consumption for data center communication.

According to the present invention, there is provided apparatus for providing protection of an optical link. The apparatus comprises a first port for coupling to the optical link and a second port for coupling to a further optical link. The apparatus further comprises a third port configured to receive an upstream optical signal to be transmitted over the optical link, and to output a downstream optical signal received over the optical link. The apparatus further comprises protection switching apparatus operable to selectively couple the third port to the first port or to the second port. The apparatus further comprises modifying apparatus configured to modify the upstream optical signal, received at the third port, before it is output from the first port, such that the switching upstream optical signal has a distinctive physical characteristic. The apparatus further comprises detecting apparatus, coupled between the first port and the third port, configured to receive a portion of an incoming optical signal, received at the first port, and to selectively detect the presence of the upstream optical signal or the downstream optical signal in the portion of the incoming signal based on the distinctive physical characteristic. The apparatus further comprises control circuitry configured to provide a control signal to the protection switching apparatus based on an output from the detecting apparatus.

An optical communication system includes an optical transmitter, a plurality of optical receivers, and a splitter that splits light transmitted by the optical transmitter to the plurality of optical receivers. The optical transmitter includes a variable-wavelength light source capable of transmitting light of a first wavelength and light of a third wavelength between the first wavelength and a second wavelength. A first optical receiver of the plurality of optical receivers includes a first optical filter having a first transmission band including the first and third wavelengths, and a first receiving unit that receives light having passed through the first optical filter. A second optical receiver of the plurality of optical receivers includes a second optical filter having a second transmission band including the second and third wavelengths, and a second receiving unit that receives light having passed through the second optical filter.

A wavelength routing SW is a large-scale optical switch device of a conventional technique, and it requires as many wavelength-tunable light sources as the number of input ports. For the wavelength-tunable light sources to achieve a stable oscillating operation across a wide wavelength range, a complicated control mechanism is necessary. This has been an obstacle in providing a large-scale optical switch device in terms of cost and circuit scale. A wavelength routing SW in the present disclosure includes N wavelength group generators, a splitting-selection unit, and MN tunable filters. Each wavelength group generator includes M fixed-wavelength light sources. Inexpensive general-purpose devices that require no control mechanism for wavelength tuning can be used as the fixed-wavelength light source. The channel loss in the optical switch device can also be reduced by using light sources with a limited narrow range of tunable wavelengths and the wavelength-dependent output port selecting function of an AWG.