Abstract: A unique sensor is used to detect a transmission impairment that may have affected incoming optical channel signals. The sensor, more specifically, selects a group of the incoming channel signals and generates a first power signal, P0, over the selected group of signals and generates a second power signals, P1, over a weighted version of the selected group of channel signals. The sensor then generates, as a function of the first and second power signals, P0 and P1, a signal indicative of whether the particular transmission impairment affected the levels of individual ones of the incoming channel signals. If so, then control apparatus offsets the impairment accordingly.

Abstract: An optical filter is disclosed. The filter includes a light distribution component having an output side. A plurality of array waveguides are configured to deliver a light signal into the light distribution component such that the light signal is incident on the output side of the light distribution component. The array waveguides are configured to adjust the location where the light signal is incident on the output side.

Abstract: An equalizer is disclosed. The equalizer includes a light distributor configured to distribute light signals received through an inlet side across an outlet side. Each of the light signals is associated with a different wavelength. The equalizer also includes optics configured to cause different light signals to separate as the light signals travel through the light distributor. The equalizer also includes a plurality of attenuators configured to attenuate the light signals in a region of the light distributor where the light signals are separated from one another.

Abstract: An add/drop node is disclosed. The add/drop node includes a first filter configured to receive a light beam having a plurality of channels. The first filter is also configured to direct channels having wavelengths falling within a plurality of first wavelength bands to a transition waveguide. The add/drop node also includes a second filter configured to receive the channels directed to the transition waveguide. The second filter is configured to direct channels having wavelengths falling within a plurality of second wavelength bands to a drop waveguide. The first filter and/or the second filter can be tunable.

Abstract: Substantial reduction in crosstalk and improved scalability for supporting high channel counts in dense wavelength division multiplexed (DWDM) systems is achieved in an optical demultiplexer arrangement that partitions the total number of input optical channels into separate demultiplexer modules, demultiplexes smaller groups of optical channels in the separate demultiplexer modules, and filters the individual optical channels at the outputs of the separate demultiplexer modules. Partitioning the total number of channels into smaller demultiplexing groups and post-filtering a reduced number of demultipexed optical channels reduces the number of non-adjacent channels that can contribute to the total crosstalk level. The modularity of the optical demultiplexer arrangement results in smaller device footprints and smaller free spectral ranges associated with the demultiplexer modules. This modularity also allows for future system upgrades without redesign and without disruption to existing service.

Abstract: An optical component is disclosed. The optical component includes an input waveguide having an expansion region expanding from an input port to a multimode port. The expansion region is configured to receive a light signal through the input port. An array waveguide grating is configured to receive a light signal from the expansion region of the input waveguide. An output waveguide has an output port configured to receive the light signal from the array waveguide grating. The output port has dimensions that are different from dimensions of the input port. In some instances, a function expressing the expansion from the input port to the multimode port includes an exponential function and/or a sinh function.

Abstract: An optical filter system is disclosed. The optical filter system includes a first filter configured to output light signals having wavelengths falling within a plurality of periodically spaced wavelength bands. A second filter in optical communication with the first filter and being configured to output light signals having wavelengths falling within a plurality of periodically spaced bands. The period of the bands associated with the first filter is different than the period of the bands associated with the second filter.

Abstract: An optical filter/combiner arrangement is used for filtering and combining optical signals in at least two wavelength bands supplied by at least two respective Wavelength Division Multiplexed (WDM) systems along the same optical fiber. More specifically, optical signals received by the optical filter/combiner arrangement from an optical fiber are appropriately filtered so that optical signals in one wavelength band are processed by components of one WDM system and optical signals in another wavelength band are processed by components in another WDM system. After processing by the respective WDM system components, the optical signals in each of the wavelength bands are then re-combined and supplied along the same optical fiber. By using the optical filter/combiner arrangement, existing WDM systems can be upgraded to higher capacity using the existing optical fiber and without replacing existing components or disrupting existing service.

Abstract: The optical component includes an array waveguide grating having a plurality of array waveguides. The optical component also includes a light distribution component configured to receive a light signal through an inlet port and distribute the light signal to a plurality of the array waveguides. The optical component further includes an output light distribution component configured to receive the light signal distributed to the array waveguides. The light distribution component is configured such that a light signal received through the inlet port with a non-periodic intensity distribution is received in the output light distribution component with a periodic intensity distribution. The period intensity distribution can have a shape that approximates a sinc function.

Abstract: An optical attenuator is disclosed attenuator includes a waveguide ending at a reflecting surface configured to reflect light signals traveling along the waveguide. The attenuator also includes an index tuner positioned adjacent to the reflecting surface. The index tuner is configured to change the index of refraction of the waveguide adjacent to the reflecting surface.

Abstract: A method of separating optical components is disclosed. The method includes obtaining a substrate structure having a plurality of optical components formed on the substrate structure. The method also includes performing a separation etch on a separation region of the substrate structure. The separation region is selected such that separating the substrate structure at the separation region separates at least one of the optical components from the other optical components.

Abstract: An optical component is disclosed. The optical component includes an input waveguide having an expansion region expanding from an input port to a multimode port. The expansion region is configured to receive a light signal through the input port. An array waveguide grating is configured to receive a light signal from the expansion region of the input waveguide. An output waveguide has an output port configured to receive the light signal from the array waveguide grating. The output port has dimensions that are different from dimensions of the input port. In some instances, a function expressing the expansion from the input port to the multimode port includes an exponential function and/or a sinh function.

Abstract: An optical component is disclosed. The optical component includes a light distribution component having a light signal carrying region. The component also includes an index tuner configured to tune the index of refraction of the light signal carrying region so as to generate a functional region in the light signal carrying region. The functional region is generated such that the index of refraction of the light signal carrying region is different inside of the functional region and outside of the functional region. In some instances, the index tuner is configured to generate the functional region such that a dispersion profile of the light signal changes in response to traveling through the functional region.

Abstract: An equalizer is disclosed. The equalizer includes a light distributor configured to distribute light signals received through an inlet side across an outlet side. Each of the light signals is associated with a different wavelength. The equalizer also includes optics configured to cause different light signals to separate as the light signals travel through the light distributor. The equalizer also includes a plurality of attenuators configured to attenuate the light signals in a region of the light distributor where the light signals are separated from one another.

Abstract: An optical component is disclosed. The optical component includes an array waveguide grating having a plurality of array waveguides. The optical component also includes a light distribution component configured to receive a light signal through an inlet port and distribute the light signal to a plurality of the array waveguides. The optical component further includes an output light distribution component configured to receive the light signal distributed to the array waveguides. The light distribution component is configured such that a light signal received through the inlet port with a non-periodic intensity distribution is received in the output light distribution component with a periodic intensity distribution. The period intensity distribution can have a shape that approximates a sinc function.

Abstract: An optical component is described. The optical component includes a light distribution component having a light signal carrying region for carrying a light signal through the light distribution component. The optical component also includes a functional region positioned in the light distribution component such that the light signal carrying region extends through at least a portion of the functional region. The index of refraction of the light signal carrying region inside of the functional region is different from the index of refraction of the light signal carrying region outside of the functional region. Additionally, the functional region is shaped such that the dispersion profile of the light signal changes in response to traveling through the functional region. In some instances, the light distribution component has the geometry of a star coupler or a Rowland circle.

Abstract: An integrated wavelength router for use in a wavelength division multiplexing system is disclosed. Input waveguides deliver a plurality of optical signals to a first slab coupler which is in turn coupled to an optical grating waveguide. A second slab coupler is coupled to the output of the optical grating waveguide which is in turn coupled to output waveguides. The input and output waveguides transmit data channels of the wavelength division multiplexing system and include out-of-band signals such as a supervisory signal or a pilot signal with different channel bandwidths. WDM systems utilizing the router of the present invention can reduce power losses and therefore increase the span length of the wavelength division multiplexing system.

Abstract: A scheme is described for controlling adjacent channel crosstalk so that an optical receiver can accurately detect the presence of a signal in its respective optical channel after a loss of signal condition occurs. According to illustrative embodiments of the invention, crosstalk-induced cross-traffic is prevented so that traffic from an adjacent channel is not carried in a channel that is out of service due to a loss of signal condition. More specifically, adjacent channel crosstalk, which might otherwise exceed the receiver sensitivity threshold of the failed channel, is substantially reduced or eliminated so that a receiver will not improperly identify and lock onto an adjacent channel thereby causing the cross-traffic condition.

Abstract: A tunable dispersion compensator is disclosed. The dispersion compensator includes an array waveguide grating having a plurality of array waveguides. A component is configured to receive portions of a light signal from the array waveguide grating and to combine the portions of the light signal into an output light signal having a dispersion profile. At least a portion of the array waveguides include an effective length tuner configured to tune the effective length of an array waveguide. The effective length tuners are configured to tune the effective lengths of the array waveguides such that the dispersion profile of the output light signal is tuned.

Abstract: An optical filter system is disclosed. The optical filter system includes a first filter configured to output light signals having wavelengths falling within a plurality of periodically spaced wavelength bands. A second filter in optical communication with the first filter and being configured to output light signals having wavelengths falling within a plurality of periodically spaced bands. The period of the bands associated with the first filter is different than the period of the bands associated with the second filter.