Lightwire, Inc.

Cisco Technology, Inc.

Sioptical, Inc.

Other

Finisar Corporation

Gothoskar, Prakash

Ghiron, Margaret

Montgomery, Robert Keith

Pathak, Soham

Patel, Vipulkumar

Shastri, Kalpendu

Yanushefski, Katherine A.

Piede, David

David Piede

Vipulkumar K Patel

Prakash B Gothoskar

Kalpendu Shastri

Mark Andrew Webster

Robert Keith Montgomery

Margaret Ghiron

Soham Pathak

Katherine A Yanushefski

Mary Nadeau

Bipin Dama

Parviz Tayebati

Daniel Mahgerefteh

Kevin John McCallion

Ravi Sekhar Tummidi

Rao Yelamarty

Weizhuo Li

John Matthew Fangman

Harvey L Wagner

Neeraj Kumar Dubey

Craig Young

Bart Johnson

Duane Stackhouse

Kal Shastri

Dincer Birincioglu

Rajesh Dighde

Wenhong Qin

Zhencan (Frank) Fan

Prakash Gothoskar

Vipulkumar Patel

Embodiments herein include an optical system that passively aligns a fiber array connector (FAC) to a waveguide in a photonic chip. A substrate of the FAC is machined or etched to include multiple grooves along a common axis or plane to hold optical waveguides, or more specifically, the fibers of the optical cables in the FAC. To align the fibers to the photonic chip, one of the fibers is disposed in an alignment trench which has a width that is substantially the same as the diameter of the fiber. When the fiber registers with the alignment trench, the fiber is aligned with a waveguide disposed at the end of the trench. Because the pitch between the fibers can be precisely controlled, aligning one of the fibers using the alignment trench results in the other fibers becoming passively aligned to respective waveguides in the photonic chip.

Passive fiber optic butt coupling using a semiconductor etched feature

An silicon-on-insulator (SOI)-based photonics platform is formed to including a venting structure for encapsulating the active and passive optical components formed on the SOI-based photonics platform. The venting structure is used to allow for the encapsulated components to 'breathe' such that water vapor and gasses will pass through the package and not condensate on any of the encapsulated optical surfaces. The venting structure is configured to also to prevent dust, liquids and other particulate material from entering the package.

Vent structures for encapsulated components on an SOI-based photonics platform

A configuration for routing electrical signals between a conventional electronic integrated circuit (IC) and an opto-electronic subassembly is formed as an array of signal paths carrying oppositely-signed signals on adjacent paths to lower the inductance associated with the connection between the IC and the opto-electronic subassembly. The array of signal paths can take the form of an array of wirebonds between the IC and the subassembly, an array of conductive traces formed on the opto-electronic subassembly, or both.

Enhanced low inductance interconnections between electronic and opto-electronic integrated circuits

Embodiments disclosed herein generally relate to optical couplers for transmitting an optical signal between a waveguide in an optical device to an external light-carrying medium and vice versa. The couplers include first and second portions that extend away from the waveguide towards an optical interface that faces the light-carrying medium. The first portion is attached to the waveguide, while the second portion is not. In one example, a first end of the first portion is attached to the waveguide, while a second end, opposite the first end, faces the optical interface. The first portion may taper as it extends from the first end to the second. The second portion of the coupler may be physically separated from both the first portion and the waveguide. However, in one embodiment, the first and second portions extend in the same direction towards the optical interface.

Dual tip optical coupler

A high speed silicon-based optical modulator with control of the dopant profiles in the body and gate regions of the device reduces the series resistance of the structure without incurring substantial optical power loss. That is, the use of increased dopant values in areas beyond the active region will allow for the series resistance to be reduced (and thus increase the modulating speed of the device) without incurring too large a penalty in signal loss. The dopant profiles within the gate and body regions are tailored to exhibit an intermediate value between the high dopant concentration in the contact areas and the low dopant concentration in the carrier integration window area.

Dopant profile control for high speed silicon-based optical modulators

A plasma-based etching process is used to specifically shape the endface of an optical substrate supporting an optical waveguide into a contoured facet which will improve coupling efficiency between the waveguide and a free space optical signal. The ability to use standard photolithographic techniques to pattern and etch the optical endface facet allows for virtually any desired facet geometry to be formed&#x2014;and replicated across the surface of a wafer for the entire group of assemblies being fabricated. A lens may be etched into the endface using a properly-defined photolithographic mask, with the focal point of the lens selected with respect to the parameters of the optical waveguide and the propagating free space signal. Alternatively, an angled facet may be formed along the endface, with the angle sufficient to re-direct reflected/scattered signals away from the optical axis.

Coupling between free space and optical waveguide using etched coupling surfaces

A low loss optical waveguiding structure for silicon-on-insulator (SOI)-based arrangements utilizes a tri-material configuration including a rib/strip waveguide formed of a material with a refractive index less than silicon, but greater than the refractive index of the underlying insulating material. In one arrangement, silicon nitride may be used. The index mismatch between the silicon surface layer (the SOI layer) and the rib/strip waveguide results in a majority of the optical energy remaining within the SOI layer, thus reducing scattering losses from the rib/strip structure (while the rib/strip allows for guiding along a desired signal path to be followed). Further, since silicon nitride is an amorphous material without a grain structure, this will also reduce scattering losses. Advantageously, the use of silicon nitride allows for conventional CMOS fabrication processes to be used in forming both passive and active devices.

Ultra low-loss CMOS compatible silicon waveguides

One or more nanotaper coupling waveguides formed within an optical substrate allows for straightforward, reproducible offset launch conditions to be achieved between an incoming signal and the core region of a multimode fiber (which may be disposed along an alignment fixture formed in the optical substrate), fiber array or other multimode waveguiding structure. Offset launching of a single mode signal into a multimode fiber couples the signal into favorable spatial modes which reduce the presence of differential mode dispersion along the fiber. This approach to providing single mode signal coupling into legacy multimode fiber is considered to be an improvement over the prior art which required the use of an interface element between a single mode fiber and multimode fiber, limiting the number of propagating signals and applications for the legacy multimode fiber. An optical switch may be used to select the specific nanotaper(s) for coupling into the multimode fiber.

Offset launch mode from nanotaper waveguide into multimode fiber

A silicon-on-insulator (SOI)-based tunable laser is formed to include the gain medium (such as a semiconductor optical amplifier) disposed within a cavity formed within the SOI substrate. A tunable wavelength reflecting element and associated phase matching element are formed on the surface of the SOI structure, with optical waveguides formed in the surface SOI layer providing the communication between these components. The tunable wavelength element is controlled to adjust the optical wavelength. Separate discrete lensing elements may be disposed in the cavity with the gain medium, providing efficient coupling of the optical signal into the SOI waveguides. Alternatively, the gain medium itself may be formed to include spot converting tapers on its endfaces, the tapers used to provide mode matching into the associated optical waveguides.

SOI-based tunable laser

A silicon-insulator-silicon capacitive (SISCAP) optical modulator is configured to provide analog operation for applications which previously required the use of relatively large, power-consuming and expensive lithium niobate devices. An MZI-based SISCAP modulator (preferably a balanced arrangement with a SISCAP device on each arm) is responsive to an incoming high frequency electrical signal and is biased in a region where the capacitance of the device is essentially constant and the transform function of the MZI is linear.

Silicon-based optical modulator for analog applications

An arrangement for providing optical crossovers between waveguides formed in an SOI-based structure utilize a patterned geometry in the SOI structure that is selected to reduce the effects of crosstalk in the area where the signals overlap. Preferably, the optical signals are fixed to propagate along orthogonal directions (or are of different wavelengths) to minimize the effects of crosstalk. The geometry of the SOI structure is patterned to include predetermined tapers and/or reflecting surfaces to direct/shape the propagating optical signals. The patterned waveguide regions within the optical crossover region may be formed to include overlying polysilicon segments to further shape the propagating beams and improve the coupling efficiency of the crossover arrangement.

Optical crossover in thin silicon

An electronic dispersion compensation (EDC) arrangement for a multi-channel optical receive utilizes a time division technique to 'share' a common adaptive algorithm block between a plurality of N separate channels. The algorithm block embodies a specific algorithm associated with correcting/updating tap weights for the delay lines forming the equalizing elements, and a time slot assignment element is used in conjunction with the algorithm block to control the access of the various channels to the algorithm block. In situations where certain channels experience a greater degree of dispersion than others, the time slot assignment element may be configured to allot a greater number of time slots to the affected channels.

Common electronic dispersion compensation arrangement for use with multiple optical communication channels

A unitary optical receiver assembly is formed to include a V-groove passively aligned with a first aspheric lens (the lens formed along a surface perpendicular to the V-groove). An optical fiber is disposed along the V-groove and is used to bring the received optical signal into the unitary assembly. Upon passing through the first aspheric lens, the received optical signal will intercept a 45&#xb0; turning mirror wall that directs the signal downward, through a second aspheric lens (also molded in the unitary assembly), and then into a photosensitive device. Advantageously, the photosensitive device is disposed in passive alignment with the second aspheric lens, allowing for a received signal to be coupled from an incoming optical fiber to a photosensitive device without needing any type of active alignment therebetween.

Dual-lensed unitary optical receiver assembly

A fiber optic communication system for receiving an electronic digital data signal and transmitting the same, comprising an optical signal source adapted to receive the digital data signal and to produce a frequency modulated optical signal from a directly modulated semiconductor laser; an optical spectrum reshaper adapted to convert the frequency modulated optical signal into an amplitude modulated optical signal; and compensation apparatus for compensating for the adverse effects of the thermal chirp normally induced in the frequency modulated optical signal by modulating the semiconductor laser with the electronic digital data signal.

Thermal chirp compensation systems for a chirp managed directly modulated laser (CML&#x2122;) data link

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Allentown, PA, United States of America

David Piede