Patents Represented by Attorney, Agent or Law Firm Wendy W. Koba
  • Patent number: 7519254
    Abstract: A microbend-induced fiber grating is formed from a section of optical fiber configured to exhibit “splitting” between the resonant wavelengths supported by the TE and TM components of the LP1m mode and the resonant wavelength supported by the odd/even HE2m components of the LP1m mode. Since only the TE and TM components are polarization dependent, by splitting and shifting the resonant wavelengths for these modes away from a system-desired wavelength(s) supported by the odd/even HE modes, a polarization insensitive microbend-induced fiber grating can be formed. A fiber core configuration including a central core region, trench and ring is formed to exhibit a large radial gradient in core refractive index profile, with a significantly steep transition between the ring index and the trench index, to provide the desired splitting between the (undesired, polarization sensitive) TE/TM modes and the HE mode.
    Type: Grant
    Filed: December 21, 2006
    Date of Patent: April 14, 2009
    Inventor: Siddharth Ramachandran
  • Patent number: 7515778
    Abstract: An optical modulator is formed to include an adjustable drive arrangement for dynamically adjusting the effective length of the optical signals path(s) within the modulator. Each modulator arm is partitioned into a plurality of segments, with each segment coupled to a separate electrical signal driver. Therefore, the effective length of each modulator arm will be a function of the number of drivers that are activated for each arm at any given point in time. A feedback arrangement may be used with the plurality of drivers to dynamically adjust the operation of the modulator by measuring the extinction ratio as a function of optical power, turning “on” or “off” individual drivers accordingly.
    Type: Grant
    Filed: October 9, 2007
    Date of Patent: April 7, 2009
    Assignee: Lightwire, Inc.
    Inventors: Paulius Mindaugas Mosinskis, Robert Keith Montgomery, Prakash Gothoskar
  • Patent number: 7503670
    Abstract: A novelty flashlight in the form of a sparkplug, with a set of LEDs (or other appropriate light emitting devices) included in the conventional “spark” emitting end of the plug. A battery source and micro-controller are included within the sparkplug housing and used to turn the LEDs “on” and “off”. In particular, the LEDs may be controlled to strobe at a rate that simulates the actual sparking of an automotive sparkplug. Alternatively, the pulsing of the LEDs may be fast enough such that the LEDs appear to be always “on”. An activation button is included on the outer housing the sparkplug for a user to control the operation of the flashlight.
    Type: Grant
    Filed: July 20, 2006
    Date of Patent: March 17, 2009
    Inventor: Tobi D. Mengle
  • Patent number: 7499620
    Abstract: A method and structure for reducing optical signal loss in a silicon waveguide formed within a silicon-on-insulator (SOI) structure uses CMOS processing techniques to round the edges/corners of the silicon material along the extent of the waveguiding region. One exemplary set of processes utilizes an additional, sacrificial silicon layer that is subsequently etched to form silicon sidewall fillets along the optical waveguide, the fillets thus “rounding” the edges of the waveguide. Alternatively, the sacrificial silicon layer can be oxidized to consume a portion of the underlying silicon waveguide layer, also rounding the edges. Instead of using a sacrificial silicon layer, an oxidation-resistant layer may be patterned over a blanket silicon layer, the pattern defined to protect the optical waveguiding region.
    Type: Grant
    Filed: September 6, 2006
    Date of Patent: March 3, 2009
    Assignee: Lightwire, Inc.
    Inventors: Vipulkumar Kantilal Patel, Prakash Gothoskar, Robert Keith Montgomery, Margaret Ghiron
  • Patent number: 7483597
    Abstract: An optical modulator is formed to include a plurality of separate electrodes disposed along one arm, the electrodes having different lengths and driven with different signals to provide for multi-level signaling (e.g., PAM-4 signaling). By using separate drivers to energize the different sections, the number of sections energized at a given point in time will define the net phase shift introduced to the optical signal. The total length of the combined modulator sections is associated with a ? phase shift (180°). Each section is driven by either a digital “one” or “zero”, so as to create the multi-level modulation. An essentially equal change in power between adjacent transmitted symbols is accomplished by properly adjusting the lengths of each individual section.
    Type: Grant
    Filed: October 17, 2007
    Date of Patent: January 27, 2009
    Assignee: Lightwire, Inc.
    Inventors: Kalpendu Shastri, Bipin Dama
  • Patent number: 7455257
    Abstract: An automated reel for use by divers comprises a battery-operated motor in communication with a take-up reel through a gearing arrangement, where the activation/de-activation of the motor is controlled by a tension-sensing mechanism. In operation, when the mechanism senses that there is “slack” in the safety cord, the mechanism will turn “on” the motor, which will then cause the reel to rotate (via the gearing arrangement) to wind up the slack safety cord. Once tension is restored on the line, the mechanism will turn “off” the motor. A manual override switch may be included for situations where the diver desires to retain control of winding/unwinding of the safety cord. A line leveler arrangement may be used in conjunction with the reel so as to evenly distribute the safety cord across the extent of the reel.
    Type: Grant
    Filed: September 13, 2006
    Date of Patent: November 25, 2008
    Inventor: Dennis Alfred Kaleta
  • Patent number: 7447395
    Abstract: A silicon-based optical modulator structure includes one or more separate localized heating elements for changing the refractive index of an associated portion of the structure and thereby providing corrective adjustments to address unwanted variations in device performance. Heating is provided by thermo-optic devices such as, for example, silicon-based resistors, silicide resistors, forward-biased PN junctions, and the like, where any of these structures may easily be incorporated with a silicon-based optical modulator. The application of a DC voltage to any of these structures will generate heat, which then transfers into the waveguiding area. The increase in local temperature of the waveguiding area will, in turn, increase the refractive index of the waveguiding in the area. Control of the applied DC voltage results in controlling the refractive index.
    Type: Grant
    Filed: June 6, 2007
    Date of Patent: November 4, 2008
    Assignee: SiOptical, Inc.
    Inventors: Robert Keith Montgomery, Margaret Ghiron, Prakash Gothoskar, Paulius Mindaugas Mosinskis, Vipulkumar Patel, Kalpendu Shastri, Mark Webster
  • Patent number: 7440703
    Abstract: An electro-optic modulator arrangement for achieving switching speeds greater than 1 Gb/s utilizes pre-emphasis pulses to accelerate the change in refractive index of the optical waveguide used to form the electro-optic modulator. In one embodiment, a feedback loop may be added to use a portion of the modulated optical output signal to adjust the magnitude and duration of the pre-emphasis pulses, as well as the various reference levels used for modulated. For free carrier-based electro-optic modulators, including silicon-based electro-optic modulators, the pre-emphasis pulses are used to accelerate the movement of free carriers at the transitions between input signal data values.
    Type: Grant
    Filed: February 22, 2006
    Date of Patent: October 21, 2008
    Assignee: SiOptical, Inc.
    Inventors: Kalpendu Shastri, Prakash Gothoskar, Margaret Ghiron, Vipulkumar Patel, Robert Keith Montgomery, Soham Pathak, Katherine A. Yanushefski
  • Patent number: 7440664
    Abstract: A microstructured optical waveguide is formed to include a periodic sequence of “plugs” of optically active material within the inner cladding air tunnels. The plugs are utilized as a grating structure for generating resonant and periodic structures. The waveguide (in one embodiment, an optical fiber) is tunable by changing the spacing of the plugs (e.g., heating the structure, changing the pressure within the structure, etc.), or by modifying the initial spacing of the plugs during the formation of the microstructured optical waveguide (i.e., by modifying the “dipping frequency” of the waveguide into a reservoir of optically active material). In general, any number of different types of optically active material may be used to form the plugs, where two or more different materials may be used in the same structure, and introduced in an alternating fashion.
    Type: Grant
    Filed: April 8, 2003
    Date of Patent: October 21, 2008
    Assignee: Fitel USA Corp.
    Inventors: Benjamin J. Eggleton, Justin D. Ging, Arturo Hale, Charles Kerbage
  • Patent number: 7437046
    Abstract: An optical transmission fiber is formed to include a relatively low-index, relatively thin outer cladding layer disposed underneath the protective polymer outer coating. Stray light propagating along an inner cladding layer(s) within the fiber will be refracted into the thin outer cladding (by proper selection of refractive index values). The thin dimension of the outer cladding layer allows for the stray light to “leak” into the outer coating in a controlled, gradual manner so as to minimize heating of the coating associated with the presence of stray light. The inventive fiber may also be bent to assist in the movement of stray light into the coating.
    Type: Grant
    Filed: February 12, 2007
    Date of Patent: October 14, 2008
    Assignee: Furukawa Electric North America, Inc.
    Inventors: David John DiGiovanni, Yoshihiro Emori, Michael Fishteyn, Clifford Headley
  • Patent number: 7415184
    Abstract: An arrangement for providing optical coupling into and out of a relatively thin silicon waveguide formed in the SOI layer of an SOI structure includes a lensing element and a defined reference surface within the SOI structure for providing optical coupling in an efficient manner. The input to the waveguide may come from an optical fiber or an optical transmitting device (laser). A similar coupling arrangement may be used between a thin silicon waveguide and an output fiber (either single mode fiber or multimode fiber).
    Type: Grant
    Filed: January 11, 2007
    Date of Patent: August 19, 2008
    Assignee: SiOptical Inc.
    Inventors: Margaret Ghiron, Prakash Gothoskar, John Fangman, Robert Keith Montgomery, Mary Nadeau
  • Patent number: 7409327
    Abstract: A method for forming a hybrid active electronic and optical circuit using a lithography mask. The hybrid active electronic and optical circuit comprising an active electronic device and at least one optical device on a Silicon-On-Insulator (SOI) wafer. The SOI wafer including an insulator layer and an upper silicon layer. The upper silicon layer including at least one component of the active electronic device and at least one component of the optical device. The method comprising projecting the lithography mask onto the SOI waver in order to simultaneously pattern the component of the active electronic device and the component of the optical device on the SOI wafer.
    Type: Grant
    Filed: February 15, 2002
    Date of Patent: August 5, 2008
    Assignee: SiOPTICAL Inc.
    Inventor: Shrenik Deliwala
  • Patent number: 7373052
    Abstract: An arrangement for providing passive alignment between an optical fiber and the “tip” of a nanotaper coupling waveguide (the nanotaper formed within the SOI layer of an SOI-based optoelectronic arrangement). The arrangement includes a separate fiber carrier support element, including a longitudinal V-groove for supporting the fiber and an alignment feature formed parallel thereto. The SOI structure is formed to include an associated alignment slot, so that as the fiber carrier is positioned over and attached to the SOI structure, the alignment feature and alignment slot will mate together and provide passive alignment of the optical fiber to the nanotaper waveguide tip.
    Type: Grant
    Filed: May 2, 2007
    Date of Patent: May 13, 2008
    Assignee: SiOptical, Inc.
    Inventors: Mary Nadeau, John Fangman
  • Patent number: 7362712
    Abstract: In accordance with the teachings of the present invention, a method and apparatus is presented for determining minutes of outage. Information associated with a facility hierarchy is acquired. In one embodiment, the facility hierarchy is a SONET facility hierarchy. Outage is determined for each level in the hierarchy and a correlation is performed on the outages associated with each level in the hierarchy.
    Type: Grant
    Filed: December 29, 2003
    Date of Patent: April 22, 2008
    Assignee: AT&T Corp.
    Inventors: Hossein Eslambolchi, Kerrie Linker, Alexander Novokshanov, Harold J. Stewart, Denis Yankin
  • Patent number: 7358585
    Abstract: A silicon-based IR photodetector is formed within a silicon-on-insulator (SOI) structure by placing a metallic strip (preferably, a silicide) over a portion of an optical waveguide formed within a planar silicon surface layer (i.e., “planar SOI layer”) of the SOI structure, the planar SOI layer comprising a thickness of less than one micron. Room temperature operation of the photodetector is accomplished as a result of the relatively low dark current associated with the SOI-based structure and the ability to use a relatively small surface area silicide strip to collect the photocurrent. The planar SOI layer may be doped, and the geometry of the silicide strip may be modified, as desired, to achieve improved results over prior art silicon-based photodetectors.
    Type: Grant
    Filed: November 17, 2004
    Date of Patent: April 15, 2008
    Assignee: SiOptical, Inc.
    Inventors: Vipulkumar Patel, Margaret Ghiron, Prakash Gothoskar, Robert Keith Montgomery, Soham Pathak, David Piede, Kalpendu Shastri, Katherine A. Yanushefski
  • Patent number: 7327302
    Abstract: An asynchronous sampling arrangement utilizes sampling of both a high speed data signal and a trigger (clock) signal. The data signal may be either an optical signal or an electrical signal. The data and trigger signals are sampled in parallel by two separate gates, the gates based on the same strobe frequency. The samples corresponding to the trigger signal are then processed through an algorithm that determines the time-base related to the sampled signal. This established time-base is then used to reconstruct the sampled version of the high data rate input signal waveform.
    Type: Grant
    Filed: February 10, 2006
    Date of Patent: February 5, 2008
    Assignee: PicoSolve Inc.
    Inventors: Mathias Westlund, Peter Andrekson
  • Patent number: 7327911
    Abstract: An improvement in the reliability and lifetime of SOI-based opto-electronic systems is provided through the use of a monolithic opto-electronic feedback arrangement that monitors one or more optical signals within the opto-electronic system and provides an electrical feedback signal to adjust the operation parameters of selected optical devices. For example, input signal coupling orientation may be controlled. Alternatively, the operation of an optical modulator, switch, filter, or attenuator may be under closed-loop feedback control by virtue of the inventive monolithic feedback arrangement. The feedback arrangement may also include a calibration/look-up table, coupled to the control electronics, to provide the baseline signals used to analyze the system's performance.
    Type: Grant
    Filed: October 19, 2005
    Date of Patent: February 5, 2008
    Assignee: SiOptical, Inc.
    Inventors: David Piede, Kalpendu Shastri, Robert Keith Montgomery, Prakash Gothoskar, Vipulkumar Patel, Mary Nadeau
  • Patent number: 7298949
    Abstract: An SOI-based photonic bandgap (PBG) electro-optic device utilizes a patterned PBG structure to define a two-dimensional waveguide within an active waveguiding region of the SOI electro-optic device. The inclusion of the PBG columnar arrays within the SOI structure results in providing extremely tight lateral confinement of the optical mode within the waveguiding structure, thus significantly reducing the optical loss. By virtue of including the PBG structure, the associated electrical contacts may be placed in closer proximity to the active region without affecting the optical performance, thus increasing the switching speed of the electro-optic device. The overall device size, capacitance and resistance are also reduced as a consequence of using PBGs for lateral mode confinement.
    Type: Grant
    Filed: January 24, 2005
    Date of Patent: November 20, 2007
    Assignee: SiOptical, Inc.
    Inventors: Prakash Gothoskar, Margaret Ghiron, Robert Keith Montgomery, Vipulkumar Patel, Soham Pathak, David Piede, Kalpendu Shastri, Katherine A. Yanushefski
  • Patent number: 7280998
    Abstract: A virtual data warehouse (the functional equivalent of a conventional data warehouse) that provides aggregated views of the complete data inventory. The virtual data warehouse contains metadata, which is used to form a logical enterprise data model that is part of the database of record (DBOR) infrastructure. Each legacy back-end database system is published on the infrastructure, with its metadata extracted and used as noted above. The infrastructure software uses standard J2EE, JMS and reusable EJBs, for transactional unit requests, and ETL (extract-transform-load) tools for real-time bulk loading of data.
    Type: Grant
    Filed: July 22, 2004
    Date of Patent: October 9, 2007
    Assignee: AT&T Corp.
    Inventors: Roger Aboujaoude, Hossein Eslambolchi, Frank Ianna, Prakash Vasa
  • Patent number: 7271916
    Abstract: A fiber characterization arrangement utilizes Fourier domain optical coherence tomography (FDOCT) to measure the cross-section of optical fibers, thus providing information sub-surface features, coating thickness/concentricity and stress-induced birefringence under tension. The FDOCT technique can also be used to study microstructured fibers. By making FDOCT measurements on a fiber placed in a cavity, the geometric and optical thickness of the fiber can be simultaneously measured, allowing for the determination of the refractive index of the fiber.
    Type: Grant
    Filed: February 23, 2004
    Date of Patent: September 18, 2007
    Assignee: Fitel USA Corp
    Inventors: Jayesh Jasapara, Andrew D. Yablon