Abstract: Optical packages are disclosed. In one aspect, an optical package may include a surface, a microelectronic device coupled with the surface, a first waveguide coupled with the microelectronic device, a second waveguide having a first end that is evanescently coupled with the first waveguide and a second end, a first thickness of a cladding material disposed between the second end and the surface, and a second thickness of a cladding material disposed between the first end and the first waveguide. The first thickness may be greater than the second thickness. Methods of making the optical packages are also disclosed. Apparatus and methods of aligning operations on optical packages are also disclosed.

Abstract: A point to strip optical communication system (200) for transmitting light between a first housing (102) and a second housing (104) of a device is provided. The point to strip optical communication system (200) includes a point optical communication element (202) that is capable of emitting light. The point optical communication element (202) is coupled to either the first housing (102) or the second housing (104). The point to strip optical communication system (200) also includes a strip optical communication element (204) that is coupled to either the first housing (102) or the second housing (104) to which the point optical communication element (202) is not coupled. The length of the strip optical communication element (204) corresponds to the travel distance of the first housing (102) and the second housing (104). The strip optical communication element (204) is located to coincide with the travel path of the point optical communication element (202).

Abstract: According to embodiments of the present invention, an optical waveguide includes a high dielectric constant core material relative to the cladding material. The cladding material has an index of refraction that is adjustable in response to an electrical stimulus.

Abstract: There is provided a fiber optic transmission system, comprising: an optical signal source adapted to produce a frequency modulated signal; and a multi-ring resonator optical spectrum reshaper (OSR) adapted to convert the frequency modulated signal into a substantially amplitude modulated signal. And there is provided a method for transmitting an optical signal through a fiber comprising: producing a frequency modulated signal; passing the frequency modulated signal through a multi-ring resonator optical spectrum reshaper (OSR) so as to convert the frequency modulated signal into a substantially amplitude modulated signal; and passing the substantially amplitude modulated signal into the fiber.

Abstract: An OADM includes optical input and output; first and second bandpass filters with a first pass band, optically coupled to the optical input and output, respectively; third and fourth bandpass filters with a second pass band, optically coupled to reflection ports of the first and second bandpass filters, respectively; first and second cascaded series of channel filter assemblies optically coupled to the transmission ports of the first and second bandpass filters, respectively, and third and fourth cascaded series of channel filter assemblies optically coupled to the transmission ports of the third and fourth bandpass filters, respectively. The OADM may be extended or upgraded so as to accommodate the throughput of additional channels or wavelengths by extending the number of filters within each cascaded series of bandpass filters, where the transmission ports of the additional bandpass filters are optically coupled to respective additional cascaded series of channel filter assemblies.

Abstract: A tunable optical filter comprises an optical switch having a single first optical port and a plurality of second optical ports; a plurality of band pass filters, each one of the band pass filters optically coupled to a respective second optical port; and an optical multiplexer having a plurality of inputs and a single output, each input optically coupled to a respective band pass filter, wherein the optical switch delivers a plurality of optical channels to a selected one of the band pass filters, the selected band pass filter transmitting a single selected optical channel to an input of the optical multiplexer. Alternatively, the multiplexer may be substituted by a second optical switch. Optionally, the band pass filters may reflect other channels back to the plurality of second optical ports.

Abstract: An optical system includes semiconductor lasers arranged in the direction of the slow axis of the laser beam, an optical means which makes parallel the collimated laser beams, an optical member which is provided with inlet and outlet faces which are positioned in perpendicular to the optical axis of laser beams and total reflection surfaces which are opposed to each other at a space where the component in the direction of the slow axis of the laser beam entering from the light inlet face repeats internal reflection, and emits from the light outlet face a slow axis uniform laser beam, and an imaging optical means which images the slow axis uniform laser beam on a surface as a linear line beam extending in the direction of the slow axis.

Abstract: Fiber optic devices including volume Bragg grating (VBG) elements are disclosed. A fiber optic device may include one or more optical inputs, one or more VBG elements, and one or more optical receivers. Methods for manufacturing VBG elements and for controlling filter response are also disclosed. A VBG chip, and fiber optic devices using such a chip, are also provided. A VBG chip includes a monolithic glass structure onto which a plurality of VBGs have been recorded.

Abstract: An in-line, distributed optical fiber filter comprises a core region with a raised refractive index (with respect to the surrounding cladding material) so as to allow for total internal reflection (TIR) of the desired transmission wavelength(s). One or more raised index features are formed within the cladding region and are configured so as to result in mode mixing between the cladding mode and core mode at determined wavelength(s) to be removed by filtering. The parameters associated with determining the proper core specifications and cladding specifications can be separately determined to provide for enhanced performance in terms of both filtering unwanted signals and propagation of desired communication signals.

Abstract: The specification describes an optical fiber device wherein a LOM is converted to an HOM prior to entering the gain section. The gain section is a few mode fiber that supports the HOM. The output from the gain section, i.e. the HOM, may be utilized as is, or converted back to the LOM. With suitable design of the few mode fiber in the gain section of the device, the effective area, Aeff, may be greater than 1600 ?m2. The large mode separation in the gain section reduces mode coupling, allowing greater design freedom and reducing the bend sensitivity of the optical fiber.

Abstract: An architecture that enables one to realize a FIR transversal filter with apodized, interlaced bipolar tap coefficients (an). The tap coefficients, an, are varied via the control of the optical powers emitted by an array of WDM laser sources. Also, a filter architecture where tap coefficients can be agilely reconfigured in both polarity and magnitude. One chirped fiber-grating may be used to implement a series of wavelength-dependent tap-weights. The filter designs can be utilized to eliminate the low-pass response centered at DC, allowing one to place the center frequency (fc)1 of the first passband at a targeted intermediate frequency (IF).

Abstract: Fiber stub interface for reducing cladding mode light. The fiber stub can be implemented in an optical transmission device. The optical transmission device can be a transceiver that also includes an optical signal receiver. The fiber stub includes an optical fiber and a ferrule. The optical fiber includes both a core and a cladding. The ferrule includes a glass material with a refractive index that is greater than the refractive index of at least a portion of the optical fiber. As a result, the cladding modes are refracted into the ferrule and away from the core, thereby reducing the chance that they are transmitted to an external optical fiber. An absorptive layer can be applied to an outer surface of the ferrule to absorb the refracted cladding modes.

Abstract: Light pulses can be stopped and stored coherently, with an all-optical process that involves an adiabatic and reversible pulse bandwidth compression occurring entirely in the optical domain. Such a process overcomes the fundamental bandwidth-delay constraint in optics, and can generate arbitrarily small group velocities for light pulses with a given bandwidth, without the use of any coherent or resonant light-matter interactions. This is accomplished only by small refractive index modulations performed at moderate speeds and has applications ranging from quantum communications and computing to coherent all-optical memory devices. A complete time reversal and/or temporal/spectral compression and expansion operation on any electromagnetic field is accomplished using only small refractive index modulations and linear optical elements.

Abstract: An optical device for optical communication includes a first main electrode disposed between a first splitter and a second splitter on a first arm. A first auxiliary electrode is disposed between the second splitter and a third splitter on the first arm. A second main electrode and a second auxiliary electrode are disposed between a third splitter and a fourth splitter on a second arm. The second main electrode is provided on the second arm at the first port side, and the second auxiliary electrode is provided on the second arm at the second port side. By such disposition of the first and second auxiliary electrodes, input signal light applied through a third port or a fourth port acts on the first main electrode prior to the first and second auxiliary electrodes. Therefore, the input signal light will not be affected by the first and second auxiliary electrodes.

Abstract: In a multi-mode interference waveguide (MMI) of a sheet shape spreading in the length direction and the width direction, the length of the multi-mode interference waveguide is set to such a length that the unique mode interferes in the length direction, thereby reducing the coupling loss when inputting/outputting the signal light. The multi-mode interference waveguide has a maximum refraction factor portion in the thickness direction and has such a refraction factor distribution that the refraction factor is reduced as departing from the maximum refraction factor portion. Thus, it is possible to suppress mode dispersion in the thickness direction of the multi-mode interference waveguide and obtain a high transmission rate in the order of 10 Gb/s.

Abstract: A higher order mode dispersion compensating fiber includes an optical fiber and a first loss layer which is provided within the fiber and which attenuates a lower order mode propagating through the optical fiber while not attenuating a higher order mode which is higher than the lower order mode. A dispersion compensating fiber mode converter for a higher order fiber includes a single mode fiber; a higher order mode dispersion compensating fiber; and a fused and extended portion which has been formed by fusing and extending the single mode fiber and the higher order mode fiber. The fused and extended portion converts between the LP01 mode of the single mode fiber and the LP02 mode of the higher order mode dispersion compensating fiber.

Abstract: The dispersion compensator with an etalon and a mirror arranged in parallel or at a slight angle with respect to each other is constructed so that emitted light from a collimator is reflected by the etalon multiple times and then enters another collimator. The dispersion compensator also has dispersion compensating units that change temperature using a heater or equivalent in order to render the amount of dispersion variable. In addition, these dispersion compensating units are provided in multi-stage form, and the angle of the mirror, the amplitude reflectance of the etalon, and temperature are optimized to offer polygonal dispersion characteristics. This realizes a practical, variable dispersion compensator suitable for a wavelength division multiplex optical transmission system and capable of shifting a variable amount of dispersion to the plus or minus side.

Abstract: A passband filter exhibiting ultra-narrow characteristics comprising a cascaded pair of Mach-Zehnder (MZ) structures each including a plurality of resonators optically coupled to each of the arms of the MZ structures.

Abstract: A spectral scanning microscope and a method for data acquisition using a spectral scanning microscope are disclosed. A computer system is provided that encompasses a memory and a database. In combination with the computer system and/or the database, a continuous wavelength subregion that serves to illuminate the specimen can be selected from a continuous wavelength region using the spectral selection means. Also in combination with the computer system together with the spectral selection means, a detection band can be selected from the detected light beam.

Abstract: A large mode area (LMA) fiber with improved resistance to bend-induced distortions utilizes highly oscillatory modes such that the effective index of the propagating modes remains less than the bent-fiber “equivalent” refractive index over a greater portion of the core. By providing a signal mode with a reduced effective index, the “forbidden” (evanescent) region of the core is reduced, and bend-induced distortion of the propagating mode is largely avoided.

Abstract: The present invention concerns a method for performing optical dispersion compensation of wavelength division multiplexed (WDM) optical signals. The method comprises the steps of providing a compensation stage with an optical transmission medium to be used as parallel operating cascade of polarization controllers and optical birefringent elements to compensate dispersion of the WDM optical signals when being transmitted spectrally dispersed into the different wavelength channels in parallel through the parallel cascades. The method is being characterized by determining the chromatic dispersion of the optical signals at one or few different wavelength channels possibly allowing an extrapolation of the chromatic dispersion to the other wavelength channels for defining accordingly an additional feedback signal to be used for the polarization controller setting.

Abstract: A filter device provides for the modification of the group delay of an optical signal without attenuation of adjacent optical signals in a WDM optical communication systems. The filters devices may be combined and used in various methods to modify the GD and dispersion. The filters are configured and designed to provide various controllable and different amounts of GD as well as dispersion at different over a range of wavelengths.

Abstract: An optical fiber interferometer (10) with relaxed loop tolerance, and a quantum key distribution (QKD) system (200) using same is disclosed. The interferometer includes two optical fiber loops (LP1 and LP2). The loops have an optical path length (OPL) difference between them. A polarization-maintaining (PM) optical fiber section (60) of length (L60) and having fast and slow optical axes (AF and AS) optically couples the two loops. The length and fast-slow axis orientation is selected to introduce a time delay (?T1-2) between orthogonally polarized optical pulses traveling therethrough that compensates for the OPL difference. This allows for drastically relaxed tolerances when making the loops, leading to easier and more cost-effective manufacturing of the interferometer as well as related devices such as a optical-fiber-based QKD system.

Abstract: Disclosed herein is a functional tunable multichannel filter which is capable of adjusting channel spacing and/or a wavelength location using polarization controllers (?/2, (?/4). The functional tunable multichannel filter includes one or more polarization maintaining fibers, a first polarization controller (?/2), a second polarization controller (?/4) and a 3 dB coupler. Additionally, the functional tunable multichannel filter is configured to tune a wavelength and adjust channel spacing by adjusting polarization of an optical signal passing through each of the polarization maintaining fibers using the first and second polarization controllers.

Abstract: The present invention provides systems and methods that employ a continuously variable optical delay line to introduce a delay into a transmitted optical signal. The delay line comprises a holey fiber configured in a spiral layout, wherein one end of the fiber is operative to a reflective fluid reservoir and the other end in operative to an input port. A segmented piezoelectric actuator is employed to position a reflective fluid within the fiber, utilizing a commutated technique that continuously moves the fluid. A signal received at the input port is routed through the holey fiber at an angle of incidence to achieve total internal reflection. The signal traverses towards the reflective fluid, and reflects back towards the input port after coming into contact with the fluid's surface. The delay introduced into the signal is a function of the distance traveled through the delay line.

Abstract: An optical receiver includes a first light receiving element to convert an optical signal to an electric signal and to output the electric signal from one end. A light receiving element row is connected to the other end of the first light receiving element to supply electric power to the first light receiving element. The light receiving element row includes a plurality of second light receiving elements connected in series.

Abstract: Systems and method for manipulating optical pulses to implement an optical switch and for pulse shaping (e.g., pulse compression and/or compression) are disclosed. In one embodiment, the system comprises an optical switch apparatus that includes a plurality of resonators optically coupled to a waveguide, two output waveguides, an input light source, a control light source. The system selects some of the input signals emitted from the input light course using control signals emitted from the control light source to route to one of the output waveguides. In another embodiment, the system includes a waveguide optically coupled to a plurality of resonators, input light source, optional resonator modules that can change the refractive index of the resonators, and an optional amplifier. This system can change the shape of the pulses by changing a number of parameters, such as the incoming pulse amplitude and/or the refractive index of the resonators.

Abstract: An optical delay element including a photonic crystal line defect optical waveguide is disclosed that has a large group refractive index and has small or nearly constant wavelength dispersion of the group refractive index in a wide wavelength region for practical use. The optical delay element includes a line defect optical waveguide formed in a photonic crystal structure, and the volume of the line defect optical waveguide is less than the volume of a single line defect optical waveguide. Thereby, the waveguide band of the line defect optical waveguide has two zero points in the third order dispersion curve of the line defect optical waveguide, and the sign of the third order dispersion curve is inverted near the zero points.

Abstract: An apparatus for combining laser beams into a single high power output beam. The apparatus includes a self-imaging waveguide (SIWG) with parallel reflective elements that have a length that is an integer multiple of the self-imaging or Talbot length of the waveguide or an integer fraction of this self-imaging length. The apparatus also includes a system for controlling the phase of each of laser beams provided to an inlet of the waveguide. The phases are controlled, e.g., with phase shifters using active feedback or control signals from the inlet to the waveguide, such that a coherently combined beam is produced at the outlet of the waveguide; and this beam is typically a high power beam of 1 kW or higher. The phase shifters are often controlled to phase-lock the input beams and may be operated to steer or aim the output beam from the waveguide.

Abstract: An optical communication system can increase a minimum optical reception level or the number of connectable optical receivers by controlling optical output levels of its optical transmitter. The optical communication system includes the optical transmitter having an optical variable splitting controller for splitting received light into N parts and supplies them to N optical fibers, and N optical receivers for receiving the signals sent via the N optical fibers. The optical variable splitting controller regulates its optical output levels to be supplied to the N optical fibers by controlling the optical coupling ratios. For example, the optical variable splitting controller may regulate its optical output levels by controlling its optical coupling ratios such that optical reception levels become equal for all the N optical receivers.

Abstract: This invention is a tunable dispersion compensation apparatus that suppresses the effects of the transmission channel dispersion which impedes transmission when optical signals used in high-speed communications are transmitted across long distances among various points.

Abstract: A large mode area, gain-producing optical fiber is configured to support multiple transverse modes of signal radiation within its core region. The fiber is a hybrid design that includes at least two axial segments having different characteristics. In a first axial segment the transverse refractive index profile inside the core is not radially uniform being characterized by a radial dip in refractive index. The first segment supports more than one transverse mode. In a second axial segment the transverse refractive index profile inside the core is more uniform than that of the first segment. The two segments are adiabatically coupled to one another. Illustratively, the second segment is a terminal portion of the fiber which facilitates coupling to other components. In one embodiment, in the first segment M12>1.0, and in the second segment M22<<M12. In a preferred embodiment, M12>>1.0 and M22˜1.0.

Abstract: An apparatus in one example comprises one or more light sources, one or more long period Bragg gratings that are optically coupled with the one or more light sources, and one or more amplification fibers that are optically coupled with the one or more long period Bragg gratings. The one or more light sources send one or more pump optical signals to one or more of the one or more long period Bragg gratings. The one or more of the one or more long period Bragg gratings transmit the one or more pump optical signals to one or more of the one or more amplification fibers. The one or more of the one or more amplification fibers absorb one or more of the one or more pump optical signals and emit one or more output signals. The one or more of the one or more long period Bragg gratings attenuate one or more of the one or more output signals.

Abstract: A tunable dispersion compensator includes a collimating unit that collimates an incident light to output a parallel light, a parallel shifting unit that spatially shifts the parallel light from the collimating unit within a predetermined range, and an optical-path-length providing unit that provides optical path length of light corresponding to a position at which light output from the parallel shifting unit is input.

Abstract: The system of a variable lightwave functional apparatus comprising: an acousto-optical modulator for outputting wavelength multiplexed light containing a plurality of pulses having a first wavelength interval; a coupler arranged at an output of said acousto-optical modulator; a polarization branching/coupling device having a first port to a third port, for branching the output form said coupler, which is entered from said first port into the polarization branching/coupling device, to both said second port and said third port; an optical amplifier connected to said second port of said polarization branching/coupling device; and said variable lightwave functional circuit and arranged between said second port of said polarization branching/coupling device and said optical amplifier; wherein: multi-wavelength oscillation light is outputted from said coupler by laser light from said acousto-optical modulator.

Abstract: The system of a variable lightwave functional apparatus comprising: an optical amplifier for outputting wavelength multiplexed light containing a plurality of pulses having a first wavelength interval; a polarization branching/coupling device having a first port to a third port, for branching output from said optical amplifier, which is entered from said first port into the polarization branching/coupling device, to both said second port and said third port; a coupler arranged at the second port of said polarization branching/coupling device; and said variable lightwave functional circuit, and arranged between said third port of said polarization branching/coupling device and said coupler; wherein: said wavelength multiplexed light containing said plural pulses having said first wavelength interval is converted into wavelength multiplexed light containing a plurality of pulses having a second wavelength interval in response to lateral pressure applied to said polarization-maintaining optical fiber, and said c

Abstract: The specification describes an optical fiber device for propagating and recompressing high energy, ultrashort pulses with minimal distortions due to nonlinearity. The device is based on propagation in a higher order mode (HOM) of a few-moded fiber. Coupling into the HOM may be accomplished using long-period gratings. Features of the HOM fiber mode that are useful for high quality pulse compression include large effective area, high dispersion and low dispersion slope. In a preferred case the long period gratings go through a turn-around point (TAP) at the wavelength of operation.

Abstract: The present invention is a method and an apparatus for resonant coupling in photonic crystal circuits. In one embodiment, a photonic crystal device comprises a substrate having a plurality of apertures formed therethrough, a photonic crystal circuit (e.g., formed by “removing” a series of apertures), and a strip waveguide extending through the apertures and coupled to the photonic crystal circuit via a surface localized photonic state formed at a surface of the photonic crystal (e.g., in the apertures). The surface localized photonic state facilitates the efficient resonant tunneling of photons from the wavelength-independent strip waveguide to the wavelength-selective photonic crystal circuit, thereby improving the filtering capabilities of the photonic crystal device.

Abstract: All optical regeneration methods and systems can be realized through an exponential amplifier and a limiting amplifier, which could be two independent devices (one piece of fiber with parametric amplification and a semiconductor optical amplifier operating at saturation state) or one single device (one piece of fiber). The signal quality and the extinction ratio after regeneration are significantly improved compared with the degraded incoming data using a parametric amplifier with the data signal to be regenerated as the pump. The regenerated data has an extinction ratio as high as 14 dB, an extinction ratio enhancement of approximately 5 dB and an approximately 5 dB negative power penalty. This regeneration schemes are format transparent (RZ and NRZ), and provide noise reduction both for bit 1's and bit 0's of the data sequence. The regeneration method and apparatus that just utilizes fibers has the additional capability of ultrafast response speed (several femtoseconds due to the Kerr effect).

Abstract: An optical multiplexing device includes an optical element having at least one set of diffractive elements, and an optical reflector. The reflector routes, between first and second optical ports, that portion of an optical signal transmitted by the diffractive element set. The diffractive element set routes, between first and multiplexing optical ports, a portion of the optical signal that is diffracted by the diffractive element set. More complex optical multiplexing functionality(ies) may be achieved using additional sets of diffractive elements, in a common optical element (and possibly overlaid) or in separate optical elements with multiple reflectors. Separate multiplexing devices may be assembled with coupled ports for forming more complex devices. The respective portions of an optical signal transmitted by and reflected/diffracted from the diffractive element set typically differ spectrally.

Abstract: An optical dispersion compensator including: a spacer element having a top surface and a bottom surface; a thin film, multi-layer mirror formed on the top surface of the spacer element, the thin film mirror having a thermally tunable reflectivity; a highly reflective mirror element formed on the bottom surface of the spacer element; and a heater element for controlling a temperature of the thermally tunable thin film mirror.

Abstract: The present invention discloses a high performance optical architecture for multiplexing and demultiplexing channels for use in high spectral efficiency optical systems. In general, the MUX and DeMUX architectures of the present invention will fall into two key sections or stages: a wavelength group section and a channel section. The group section makes use of characteristic associated with groups of multiplexed channels for separating said groups from an optical signal having a plurality of multiplexed groups. Advantageously, in preferred embodiments, the channel section is colorless (non-wavelength specific between groups) in order to reduce cost and complexity. With respect to the colorless channel section, components with free spectral ranges (FSRs) have been strategically added to provide repetitive optical filtering functions on group of channels (i.e., subsets of channels within each band of wavelengths) so that the colorless channel section can operate in any respective group identically.

Abstract: A dispersion compensating fiber whose chromatic dispersion is positive and a negative dispersion compensating fiber whose chromatic dispersion is negative are prepared, and division-multiplexed optical signals, after being guided to either dispersion compensating fiber to once shift the whole wavelength band to positivity or negativity, are subjected to fine adjustment with a dispersion compensating fiber of a reverse sign.

Abstract: An optical system having an optical fiber path suitable for propagating an optical signal at least in a first direction, and a plurality M of optical amplifiers disposed along the optical fiber path so as to divide the optical fiber path in N spans of optical fiber. The spans of optical fiber all have substantially a length Lamp and have at least one transmission optical fiber having an effective length Leff. An optical phase conjugation device is associated to one of the amplifiers of the plurality of amplifiers and is disposed in combination with a dispersion compensator. The compensator is disposed upstream from the amplifier associated to the optical phase conjugation device and is adapted for introducing an accumulated dispersion such as to substantially compensate the dispersion accumulated in a portion having a length (Lamp?Leff) of the span immediately upstream from the amplifier associated to the optical phase conjugation device.

Abstract: An optical equalizer circuit for a light source, the optical equalizer circuit comprising M optical couplers linked by differential delay lines, wherein coupling ratios for the respective M optical couplers of the equalizer circuit are calculated based on an input signal from the light source and a designed profile the optical input is to be equalized to.

Abstract: A mode coupler structure includes a discriminating structure that discriminates between various incoming modes from an input optical fiber structure. A waveguide structure is coupled to the discriminating structure that couples light not discriminated by the discriminating structure to an output optical fiber structure.

Abstract: A method of producing narrow optical pulses includes receiving first and second optical pulses having first and second widths, respectively, the second optical pulse having a delay relative to the first optical pulse, and selectively interfering the first and second optical pulses to produce a third optical pulse having a third width narrower than both said first and second widths.

Abstract: A fiber optic module is provided that effectively reduces a returned light and is manufactured by a low time and cost consuming process and electronic equipment. The fiber optic transceiver module includes a block that includes an optical waveguide and a guide that is provided to one end of the optical waveguide and is a concave portion into which an optical fiber is inserted, and a micro tile-like element that includes a light emitting element or a light receiving element is attached to the block. A light emitting part of the light emitting element or a light receiving part of the light receiving element is disposed so as to face the other end of the optical waveguide. The optical waveguide includes a branch having a blind end.

Abstract: An integrated optical waveguide based surface plasmon resonance biosensor is formed by detecting amplitude and phase of electromagnetic waves utilizing interferometry and/or optical delay configurations.

Abstract: In an optical grating device, a grating arrangement receives different wavelength output signals from a plurality of radiation sources at input ports thereof, and generates therefrom a multiplexed wavelength output signal at a zero diffraction order output port of the grating arrangement. Additionally, the gating arrangement generates at least one predetermined wavelength output signal at one of a group consisting of a separate predetermined location in an at least one of a symmetric non-zero diffraction order of the grating arrangement, within the grating arrangement itself, and a combination thereof. A separate power tap is coupled to detect the power of a separate one of the at least one predetermined wavelength output signal from the grating arrangement.