Abstract: Fiber optic transmitter and receiver electrical elements are implemented on separate vertical boards in fiber optic modules. A single optical block implements lenses and reflecting surfaces to minimize manufacturing costs. In one embodiment the receiver and transmitter are mounted to receive and transmit vertical boards respectively to nearly face each other but being offset to avoid optical cross talk. In a second embodiment, receiver and transmitter are mounted parallel with the printed circuit boards to save additional space. The vertical boards have ground planes to minimize electrical cross talk. A shielded housing provides further shielding for EMI. Manufacturing steps of the fiber optic transceiver are disclosed which provide reduced manufacturing costs.

Abstract: A monolithic sequential coupling arrangement has two or more fused biconic couplers joined with one common optical fiber which is not spliced. The couplers are close together in a space-saving relationship exhibiting a relatively low polarization dependent loss. The non-fused fiber portions in the arrangement have each at least one adiabatic taper.

Abstract: Optical performance monitoring device for monitoring and analyzing an optical signal has a periodically movable reflective mirror to receive an input optical beam and to cyclically “scan” (deflect) the beam in a one-dimensional direction. The deflected beam at a varying deflection angle is directed to a linear variable filter (LVF) that passes a selected wavelength channel of the deflected beam in dependence upon the deflection angle. The selected channel is then passed to a photodetector via a focusing lens, typically a cylindrical lens. The device is durable, tunable, offers low loss, good wavelength registrability and spectral resolution.

Abstract: The architecture for a photonic transport network node provides for pass-through of selected channels in the absence of OEO conversion, dropping of selected other channels, and selective routing of the other dropped channels to a processing means that provides OEO conversion and 3R processing. Conveniently, these dropped channels may be multiplexed back into the switching fabric of the node to be directed in pass-through mode to any selected output destination port. The add channels are inserted at the input side of the node. In addition, a pass-through channels may selectively delayed and OEO converted if signal conditioning and/or wavelength conversion are required. The transponders, regenerators and transceivers need not be wavelength specific, allowing flexible and scaleable network configurations. This network node is upgradeable and can be augmented without disturbing traffic within the node.

Abstract: In an optical waveguide fabricated to provide spectral filtering by a periodic mode coupling between the core and cladding the spectral profile may be shifted in wavelength if the core or cladding is photosensitive. This is especially useful in the case of long period gratings used as gain flattening filters, as a relatively low dose of radiation, compared with that typically required to fabricate a Reflection Bragg Grating in the same fiber, provides a sufficient shift for filter tuning purposes. Subsequent thermal exposure can stabilize the filter performance over the expected temperature range, while exposure to higher temperature reverses the radiation induced shift.

Abstract: A integrating light pipe re-circulates color to improve efficiency. A number of color filters, such as blue, green, and red filters, on the end of the light pipe transmit a selected color and reflect the remaining light back into the light pipe, where it is spatially homogenized and re-circulated back to the output of the light pipe. The re-circulated homogenized light illuminates the filters, and the process repeats. Thus, most of the light from the light source eventually is transmitted through one of the color filters. The filters can provide straight boundaries between the resultant color beams, which are provided to a scrolling element, such as a rotating prism, rotating mirror drum, or linear oscillating optical element, and hence to a light valve. The combination of the re-circulating light pipe and scrolling element provide continuous color scrolling and efficient use of the broad-spectrum light from the light source.

Abstract: The invention relates to a bail latching device for an opto-electronic transceiver, including a pivotal latching member and a bail. The bail includes ends extending at an acute angle from a plane defined by the side arms for pivoting the latching member when the bail is rotated from a rest position to a removal position. Ideally, in the rest position, the side arms of the bail extend downwardly on each side of a front end of the transceiver. In the removal position, the bail is parallel to a removal direction, whereby the bail rotates the latching member to an unlatching position and then provides a handle to grasp while removing the transceiver from a standard cage.

Abstract: An optical digital external modulator having a cascaded arrangement of interferometers is provided. The optical modulator includes an electrode structure for applying an electric field to each interferometer in the cascade and biasing circuitry coupled to the electrode structure for biasing each interferometer at a predetermined bias point. In particular, each predetermined bias point is selected to be above quadrature and for providing improved transmission performance of digital data signals. Preferably, the modulator has a reflective design that helps to increase the modulation bandwidth, lower the drive voltage, and reduce size.

Abstract: Planar index guided vertical cavity surface emitting laser (PIG VCSEL) utilizes index guiding to provide improved optical confinement and proton implantation to improve current confinement. Index guiding is achieved by etching index guide openings (holes or partial ridges) around the optical confinement region and may be adjusted by varying the etched volume of the index guide openings (holes and partial ridges). The top contact surface area is increased in the PIG VCSEL thereby lowering contact and device resistance to improve VCSEL performance further. The PIG VCSEL is a substantially planarized device for ease of manufacture.

Abstract: A tunable PM fiber combiner is configured to be accurately alignable with and operative to combine into a single composite beam a pair of non-collimated, orthogonally polarized light beams transported over polarization maintaining (PM) optical fibers, whose mutual spatial separation may vary. The combiner includes birefringent elements, that are linearly or rotationally displaced to realize the composite beam. The resulting composite light beam may then be readily coupled (e.g. via a single mode fiber) to a downstream beam processing device, such as a Raman amplifier.

Abstract: Polarization controlling elements equivalent to quarter and half waveplates are constructed from sequences of variable retarder plates having fixed retardation axes. An endless polarization control algorithm is provided.

Abstract: A micro-optical delay element for a time-division multiplexing scheme is disclosed wherein two light beams are provided to a beam splitter/combiner (BS/C) in the absence of optical fibre. At least one beam exiting a modulator is collimated and reaches the (BS/C) unguided as a substantially collimated beam.

Abstract: A high power, single lateral mode semiconductor laser has a waveguide with regions of different widths coupled by a tapered region. The laser has a laterally confining optical waveguide having a highly reflecting first end and a second end. The optical waveguide has a first portion extending from the first end and a second portion extending from the second end. The first and second portions are coupled by a tapered waveguide. A width of the first portion is less than a width of the second portion. The first portion filters lateral optical modes higher than a fundamental lateral optical mode. An output is emitted from the second end of the optical waveguide.

Abstract: Rotate-and-pull mechanisms for fiber optic modules. The rotate-and-pull mechanisms have a lever-actuator to unlatch and withdraw a fiber optic module from a cage assembly or a module receptacle. The lever-actuator pivotally couples to the fiber optic module so that when lever-actuator is rotated about its pivot point, the lever-actuator causes the second actuator to release the fiber optic module from the cage assembly. The lever-actuator includes an actuating-tab to cause the second actuator to move when the lever-actuator is rotated. By pulling the lever-actuator away from the cage assembly, the fiber optic module is withdrawn from the cage assembly. A belly-to-belly mounting configuration is introduced for the rotate-and-pull release fiber optic modules.

Abstract: Rotate-and-pull mechanisms for fiber optic modules. The rotate-and-pull mechanisms have a lever-actuator to unlatch and withdraw a fiber optic module from a cage assembly or a module receptacle. The lever-actuator, pivotally couples to the fiber optic module so that when lever-actuator is rotated about its pivot point, the lever-actuator causes the second actuator to release the fiber optic module from the cage assembly. The lever-actuator includes an actuating-tab to cause the second actuator to move when the lever-actuator is rotated. By pulling the lever-actuator away from the cage assembly, the fiber optic module is withdrawn from the cage assembly. A belly-to-belly mounting configuration is introduced for the rotate-and-pull release fiber optic modules.

Abstract: An optical fiber laser has an output that is stabilized to adapt to changes in laser operating temperature. At the output of the laser a plurality of wavelength-selective stabilizing reflectors is provided, each having a reflectivity profile with a different center wavelength. The reflectors, typically Bragg gratings, have a relative degree of reflectivity and relative wavelength separation that results in the output power of the laser being at one or more of the reflector center wavelengths throughout the temperature change. Thus, as a temperature shift causes the wavelength of the optical energy generated in the laser gain medium to change, the grating-stabilized output of the laser shifts between one locked wavelength and another. However, the output remains stable over the extended wavelength range provided by the multiple reflectors. Such a laser is particularly useful in an amplifier system in which the laser is used as an optical pump source.

Abstract: An optical attenuator has a planar MEMS substrate supporting two optical fibers; an actuator; and a silicon vane actuatable by said actuator for a movement into and out of the optical beam passed between the fibers. The vane is configured to divert at least a portion of the optical beam off the optical axis when the element is moved into the optical beam. The vane has at least one surface disposed non-perpendicularly relative to the optical axis of the beam. The vane may be of a wedged shape.

Abstract: A method and device is disclosed for dispersion compensation of an optical signal having periodic dispersion within a multi-channels system. For example interleaved optical channels often exhibit dispersion having a characteristic that is repeated in adjacent channels. By providing a periodic device that allows for polarization dependent routing of an interleaved signal to allow for multiple passes of said signal through a multi-cavity GT etalon, having a free-spectral range that corresponds to the channel spacing, the dispersion in the interleaved signal can be lessened and practically obviated or balanced to a desired level. This invention provides a device and method to achieve that end.

Abstract: A multistage optical amplifier is disclosed with programmable gain for operation in an automatic gain control mode that has a low noise figure or an optimal or near optimal noise figure. The programmable-gain optical amplifier has several amplifying stages separated by variable optical attenuators (VOAs) and may have mid-stage access devices (MSA) such as dispersion compensating fiber or optical add/drop modules. A method of selecting attenuation values for the VOAs for realizing low noise figure for various values of the overall optical gain is also disclosed. The loss among the amplifier stages is distributed and predetermined attenuation values for the VOAs are selected so as to minimize the overall noise figure of the multistage amplifier. The predetermined attenuation levels are determined during the amplifier calibration process taking into consideration the pump power limits, nonlinearity limits in the dispersion compensating fiber and the required overall optical amplifier gain.

Abstract: A heat sink is for an element to be cooled has a thermally conductive base and a plurality of thermally conductive pins or fins extending substantially perpendicular from the base, said pins or fins being arranged in a predetermined pattern. The pins at least partially frame thermally conductive projections extending substantially perpendicular from said base which forming a discernable logo having an upper surface and sides for providing plural cooling surfaces. In this instance the 3-D logo performs cooling of the components within a package.