Abstract: Disclosed is a laser module case having a snout disposed within a wall of the case, wherein the snout may allow alignment of a laser with an optical fiber after closure of the case. The snout has an inner end, outer end and longitudinal hollow. An optical fiber assembly, also with an inner end, outer end and longitudinal hollow, is disposed within the snout hollow. An inner flange secures the snout to the optical fiber assembly at their inner ends and an outer flange secures the snout to the optical fiber assembly at their outer ends. The optical fiber assembly is of a smaller cross-sectional diameter than the snout hollow so that it may move in an X and Y-direction. The optical fiber assembly may be aligned with a laser positioned within the case after the case is closed. The aligned fiber assembly may then be secured in position by the outer flange.

Abstract: An InGaAs/InAlAs-based avalanche photodetector provides high gain and high bandwidth over a range of operating biases. A graded transition region alleviates the barrier to electron transport from the absorption region to the multiplication region when an operating bias is applied. The graded transition region is a graded bandgap material with a relatively wide bandwidth in the region closer to the multiplication region and a relatively narrow bandgap in the region closer to the absorption region. In another embodiment, a p-type dopant profile is introduced within the absorption layer to produce an electrostatic field which accelerates electrons towards the multiplication region. In another embodiment, a bi-level multiplication region with a wide bandgap ternary layer and a narrower bandgap quarternary layer is provided at an increased thickness to improve gain per unit length.

Abstract: The present invention provides an optoelectronic device, a method of manufacturing thereof, and an optical communications system including the same. The optoelectronic device includes an optical substrate coupled to a submount and including an optical device, and a signal and a ground conductor coupled to the submount, wherein the signal and ground conductors have a direction of signal propagation associated therewith, and wherein related transitions of the signal and ground conductors between the submount and the optical substrate are separated along the direction by a predetermined distance.

Abstract: The present invention provides an optoelectronic device and a method of manufacture thereof. In one embodiment, the method of manufacturing the optoelectronic device may include creating a multilayered optical substrate and then forming a self aligned dual mask over the multilayered optical substrate. The method may further include etching the multilayered optical substrate through the self aligned dual mask to form a mesa structure.

Abstract: A high speed interface for optoelectronic devices is disclosed that includes a housing adapted to receive a distal end of a fiber having a slanted end face. The end face of the fiber is optically coupled to an optoelectronic device mounted in the housing. The fiber cladding between the optoelectronic device and the fiber core may be polished or etched to reduce the thickness of the cladding to reduce the separation distance between the optoelectronic device and the slanted end face of the fiber. The reduced separation distance improves the optical coupling efficiency between the end face of the fiber and the optoelectronic device.

Abstract: A micro-lens array and a method for making are described. The micro-lens array includes a base element and a plurality of lenses formed of an epoxy and including nanoparticles. The micro-lens array is formed from a master micro-lens array, which is placed within a replica micro-lens making assembly. The master micro-lens array is coated with an anti-stiction material prior to having an elastomeric material positioned over it and cured. Removal of the elastomeric material provides a plurality of cavities, which are filled with an epoxy including nanoparticles. Curing of the epoxy finishes the fabrication of the micro-lens array. The lenses of the micro-lens array are formed from a colloidal suspension of nanoparticles and resin.

Abstract: An optoelectronic receiver having a variable transfer function to compensate for operational condition change. The receiver comprises a linear circuit having a tunable filter. A control circuit provides a signal to the tunable filter. The control circuit is connected to one or more sensors which sense one or more operational conditions. The control circuit signal is a function of the one or more sensed operational conditions. The control signal is input to the tunable filter which adjusts the linear circuit's transfer function based on the control signal. Further disclosed are an integrated circuit and optical communication system having the inventive optoelectronic receiver. A method for adjusting an optoelectronic signal in a receiver is also disclosed.

Abstract: The present invention provides an optical device. In one embodiment, the optical device includes an optical waveguide formed in or over a ridge located on a substrate. The optical device also includes a microstrip transmission line comprising a signal electrode and a ground electrode adjacent the ridge and a low-k dielectric material separating the signal and ground electrodes. The present invention also provides a method for making the optical device.

Abstract: The thermo-optic behavior of an optical path over a range of temperatures is controlled by determining a figure of merit (FoM) for the optical path and including in the path a body of NaBi(Mo1-xWxO4)2 crystalline material that enables the conditions specified by the FOM to be satisfied. The NaBi(Mo1-xWxO4)2 crystalline material is highly transparent at a wavelength of radiation propagating in the path, and has a coefficient of thermal expansion (CTE) and a refractive index n such that the CTE and dn/dT of the etalon compensate one another so as to perform frequency discrimination that is essentially temperature insensitive over the range ?T. The NaBi(Mo1-xWxO4)2 crystalline material exhibits temperature independent transmission characteristics at about room temperature and at a wavelength of about 1550 nm.

Abstract: Laser wavelength stabilization is achieved by locating a low selectivity reference filter in a reference path of a laser beam. The low selectivity reference filter, with a periodicity greater than the control filter, is used together with a lookup table for the reference filter to resolve the uncertainty associated with the multivalued control filter. After the wavelength uncertainty for the control filter is resolved, the laser beam is stabilized based on the response of the control filter, as if the reference filter was not present.

Abstract: The present invention provides an optical device and a method of manufacture thereof. In one embodiment, the method of manufacturing the optical device may include isolating an end of a first layer from a cladding layer located over a mesa structure that has been formed from a substrate. The end of the first layer may be isolated from the cladding layer by encapsulating the end between second and third layers located adjacent the mesa structure.

Abstract: An optical modulator includes first and second modulator segments. The first and second modulator segments form an optical signal path for an optical signal. The optical modulator also includes an electrical signal path capable of receiving and carrying a modulation signal, which is applied to the optical signal at the first and second modulation segments to generate a modulated optical signal. An inductive element may be disposed between electrical inputs to the first and second modulator segments. The optical modulator may be an electro-absorption modulator (EAM). The inductive element may be an inductor or a transmission line segment.

Abstract: A semiconductor modulator is disclosed which exhibits a negative alpha parameter at low operating bias. The device includes at least two barrier layers with a quantum well layer therebetween. An additional layer is formed adjacent to the quantum well layer, the additional layer having a bulk bandgap energy greater than the quantum well layer so as to form a stepped well between the barrier layers.

Abstract: An optical transmitter includes a laser driver capable of receiving data and applying the data to drive a laser diode over a transmission line having first and second ends. The first end of the transmission line is coupled to an output of the laser driver. A first terminal of an amplifier is coupled to the second end of the transmission line. A second terminal of the amplifier is coupled to the laser diode. The signal amplitude applied at the first terminal controls optical output amplitude of the laser diode.

Abstract: The invention, in accordance with one aspect, is an optical assembly including a substrate, a light emitting device mounted over a major surface of the substrate and having a back face, at least one channel formed in the substrate near the back face of the light emitting device, and at least one photodetector optically coupled to the light emitted from the back face. The channel includes at least one surface adapted to receive a portion of the back face light and reflect it away from the photodetector so that the photodetector receives primarily direct light from the back face.

Abstract: A MEMS device and a method for making a MEMS device are described. The MEMS device includes a support member, an optical device, and a flexible member. In one aspect, the flexible member is formed separately from the support member and the optical device. In one aspect, the flexible member is dimensioned to enable flex in one direction while maintaining stiffness in two orthogonal directions. In one fabrication embodiment, the MEMS device is formed by etching an opening into the structural layer to create a structural support member and an optical device. The structural support member and optical device are mounted on a support substrate with a sacrificial layer. A flexible member is conformally deposited over the structural support member and the optical device and then etched. The sacrificial layer is partially etched away to leave the structural support member anchored to the support substrate.

Abstract: The invention is an optoelectronic device and method of fabrication where at least two optical devices are formed on a single semiconductor substrate, with each optical device including an active region such as a multi-quantum well region. The active devices are spatially separated and optically coupled by a passive waveguide formed over the substrate which provides butt joints with the active regions. The butt joints can be optimized independently from the active regions thus improving yield.

Abstract: The present invention provides an interferometer. In one embodiment, the interferometer includes a translucent body having a first portion and a second portion, where the second portion has at least three internal reflective sides. The interferometer also includes an interface between the first and second portions, configured to reflect a portion of an optical signal received through the first portion and transmit a remaining portion of the optical signal into the second portion. Also disclosed are a method of manufacturing an interferometer and a transmitter incorporating the interferometer or the method.

Abstract: Optical alignment between a communication optical fiber and an optical device is achieved by using a substrate including a fiber-holding channel formed in the top surface of the substrate. The channel is particularly formed to include a central fulcrum region, against which the fiber is pressed into as the fiber-to-device alignment is performed. In particular, the fulcrum functions as a pivot point to allow for the free endface of the fiber nearest the optical device to be adjusted (performing a “fine” adjustment) by manipulating the opposing end of the fiber (using a “gross” movement) until alignment with the optical device is achieved. A reduction of, for example, 14:1 between the gross movement and the fine adjustment can be achieved by using the inventive fulcrum structure.

Abstract: An optical wire board which utilizes a silicon substrate as the base for both the optical subassembly and the electrical RF transmitting circuit. An optical fiber is preferably passively aligned to the active optical device mounted on the optical subassembly using a V-groove etched into the silicon (and may include a lens or other optical element positioned between the fiber and the active device). An integrated circuit for coupling the active optical device to external contacts is preferably flip-chip mounted to the silicon substrate upon pads disposed on precisely defined edges around a cavity etched beneath the circuit, the inclusion of the cavity beneath the electrical circuit functioning to minimize the dielectric loading effect of the silicon substrate on the integrated circuit.