Grating Patents (Class 398/84)
  • Patent number: 7286732
    Abstract: An optical apparatus comprises a planar optical waveguide and at least one set of diffractive elements formed in or on the waveguide. The waveguide is arranged to confine propagating optical signals in at least one transverse dimension. The diffractive element set collectively exhibits a positional variation in diffractive amplitude, optical separation, or spatial phase over some portion of the set. The diffractive element set is collectively arranged to route, as an output optical signal, between corresponding input and output optical ports, a corresponding diffracted portion of an input optical signal. The diffractive element set is collectively arranged so that the input optical signal or the output optical signal is successively incident on the diffractive elements.
    Type: Grant
    Filed: March 13, 2007
    Date of Patent: October 23, 2007
    Assignee: LightSmyth Technologies Inc.
    Inventors: Christoph M. Greiner, Thomas W. Mossberg, Dmitri Iazikov
  • Patent number: 7286763
    Abstract: An optical add/drop multiplexer (OADM) adapted to route optical signals having at least two different bit rates. The OADM has at least two sets of DWDM channels, e.g., with channels in a first set having a first bandwidth value suitable for the transmission of 10-Gb/s signals and channels in a second set having a second bandwidth value suitable for the transmission of 40-Gb/s signals. The first and second sets occupy two different spectral bands and the first set has two subsets of interleaved channels. In one embodiment, the OADM has first and second optical branches adapted to process optical signals corresponding to first and second groups of channels, respectively. The first group includes a first subset from the first set while the second group includes the second set and a second subset from the first set. Advantageously, OADMs of the invention may be used to create independent processing paths for different groups of channels. As a result, a communication system having those OADMs can be upgraded, e.g.
    Type: Grant
    Filed: June 16, 2004
    Date of Patent: October 23, 2007
    Assignee: Lucent Technologies Inc.
    Inventors: Daniel A. Fishman, Xiang Liu, Vincent John Silverio, William A. Thompson, Jinpin Ying
  • Patent number: 7286764
    Abstract: An optical add and drop multiplexer system comprising a first module for providing a first signal; a second module for providing a second signal; and a modulator for receiving a channel of the first signal at a first location, the first location configured to actuate between a first configuration and a second configuration, wherein the modulator directs the channel of the first signal as an output signal when the first location is in the first configuration. The modulator may direct the channel of the first signal as a dropped signal when the first location is in the second configuration. The modulator may also receive a channel of the second signal from the second module at a second location configured to independently actuate between the first configuration and the second configuration.
    Type: Grant
    Filed: February 3, 2003
    Date of Patent: October 23, 2007
    Assignee: Silicon Light Machines Corporation
    Inventors: Jahja I. Trisnadi, Clinton B. Carlisle
  • Patent number: 7280761
    Abstract: An optical level calculator calculates optical powers of individual wavelengths of a through wavelength division multiplexed signal based on an input level monitor, network information, and insertion loss information 5, and obtains an optimum level for an add signal. An optical level controller controls a power of the add optical signal to the optimal level based on the calculated result, and multiplexes the through wavelength division multiplexed signal and the add optical signal.
    Type: Grant
    Filed: March 20, 2002
    Date of Patent: October 9, 2007
    Assignee: NEC Corporation
    Inventor: Yoshiaki Aono
  • Patent number: 7277640
    Abstract: The present invention overcomes problems associated with switch isolation, noise and crosstalk suppression, insertion loss, spurious reflections, wavelength tolerance, and compactness that are present in varying degrees in other add/drop systems. The present invention includes devices or components that include, but are not limited to high efficiency switchable gratings.
    Type: Grant
    Filed: November 18, 2003
    Date of Patent: October 2, 2007
    Assignee: Avago Technologies Fiber IP (Singapore) Pte Ltd
    Inventor: Thomas W. Stone
  • Patent number: 7266299
    Abstract: A tunable add/drop&continue or drop&continue module comprises two optical filters where at least one is tunable and that are arranged following one another between a branching unit for optical signals and an insertion unit follow a branching unit for optical signals. The reflection attenuation of the one tunable optical filter is lower and the transmission attenuation higher than that of the other optical filter, as a result of which the drop&continue function of the module can be realized without high circuit-oriented expense.
    Type: Grant
    Filed: August 23, 2000
    Date of Patent: September 4, 2007
    Assignee: Siemens Aktiengesellschaft
    Inventors: Harald Bock, Patrick Leisching, Alexander Richter, Detlef Stoll
  • Patent number: 7263291
    Abstract: This invention provides a system that combines a wavelength multiplexer with an FM discriminator for chirp reduction and wavelength locker in a filter to produce a wavelength division multiplexed signal with reduced chirp. A partially frequency modulation laser signal is converted into a substantially amplitude modulation laser signal. This conversion increases the extinction ratio of the input signal and further reduces the chirp. A wavelength division multiplexing (WDM) method is used for transmitting high capacity information through fiber optics systems where digital information is carried on separate wavelengths through the same fiber. Separate transmitters normally generate their respective signals that are transmitted at different wavelengths. These signals are then combined using a wavelength multiplexer to transmit the high capacity information through the fiber optic system.
    Type: Grant
    Filed: July 8, 2003
    Date of Patent: August 28, 2007
    Assignee: Azna LLC
    Inventors: Daniel Mahgerefteh, Parviz Tayebati
  • Patent number: 7254293
    Abstract: An optical switch for routing arbitrary wavelengths between optical fibers in optical networks. The optical switch may include a highly wavelength dispersive element together with a spatially dispersive element to separate the wavelengths. Broadband switch inputs and outputs may be provided for adding and dropping arbitrary wavelengths at each node of the network. Fiber demultiplexers and multiplexers may also be used to reduce the impact of mirror array yield on switch functionality.
    Type: Grant
    Filed: June 28, 2004
    Date of Patent: August 7, 2007
    Assignee: Calient Networks, Inc.
    Inventors: Roger Jonathan Helkey, Shifu Yuan, Xuezhe Zheng
  • Patent number: 7236704
    Abstract: A switchless optical add/drop module (OADM) includes: a first variable optical splitter (VOS) for splitting a composite optical signal including a plurality of channels into a first portion and a second portion; a first multi-channel variable optical attenuator (MCVOA) optically coupled to the first VOS, where the first MCVOA blocks dropped channels of the first portion, transmits express channels of the first portion, and balances power levels of each of the transmitted express channels of the first portion; a second VOS optically coupled to the first MCVOA opposite to the first VOS for combining the transmitted express channels of the first portion and added channels; and a second MCVOA optically coupled to the first VOS, where the second MCVOA blocks express channels of the second portion, transmits dropped channels of the second portion, and balances power levels of each of the transmitted dropped channels of the second portion.
    Type: Grant
    Filed: November 13, 2002
    Date of Patent: June 26, 2007
    Assignee: Avanex Corporation
    Inventor: Simon X. F. Cao
  • Patent number: 7231150
    Abstract: A temperature sensing and control method and apparatus. In one aspect of the present invention, an apparatus according to the teachings of the present invention includes an optical path disposed in semiconductor material. A four-terminal resistor is defined in the semiconductor material. At least a portion of the optical path is directed through the four-terminal resistor. The four-terminal resistor includes a first pair of terminals between which a probe current is to be injected. The four-terminal resistor also includes a second pair of terminals between which a voltage drop is to be measured so as to determine a resistance along the portion of the optical path directed through the four-terminal resistor. Temperature may be derived from the determined resistance of the four-terminal resistor. In one embodiment, the temperature of the semiconductor material may then be controlled with a heater in response to the derived temperature.
    Type: Grant
    Filed: October 23, 2002
    Date of Patent: June 12, 2007
    Assignee: Intel Corporation
    Inventors: Dean A. Samara-Rubio, Andrew C. Alduino, Christina A. Frost
  • Patent number: 7231149
    Abstract: A bidirectional optical add-drop multiplexer adds and drops optical signals having specific wavelengths among the WDM optical signals transmitted bidirectionally through one of the optical transmission lines connected between neighbor nodes in a bidirectional WDM ring network.
    Type: Grant
    Filed: February 24, 2004
    Date of Patent: June 12, 2007
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Sung-Bum Park, Yun-Je Oh, Seong-Taek Hwang
  • Patent number: 7224902
    Abstract: A time-spreading and wavelength-hopping optical encoder spreads each pulse in a modulated optical pulse signal into a predetermined pulse train including pulses with different wavelengths. The last pulse in the pulse train is delayed from the first pulse in the pulse train by an interval that is longer than the pulse period of the modulated optical pulse signal. Interference is avoided by dividing the pulse train into successive delay groups that are equal in length to the pulse period of the modulated data pulse signal, and having each wavelength appear in only one delay group. If encoders producing differently structured pulse trains are used in an optical multiplexer, interference is avoided by having the same wavelength appear only at different positions within the delay groups of different pulse trains. Long delays can be used to multiplex a relatively large number of channels, even at high transmission rates.
    Type: Grant
    Filed: September 25, 2002
    Date of Patent: May 29, 2007
    Assignee: OKI Electric Industry Co., Ltd.
    Inventor: Akihiko Nishiki
  • Patent number: 7224867
    Abstract: Method and apparatus are contemplated for receiving from an input, an optical signal in a volume hologram comprising a transfer function that may comprise temporal or spectral information, and spatial transformation information; diffracting the optical signal; and transmitting the diffracted optical signal to an output. A plurality of inputs and outputs may be coupled to the volume hologram. The transformation may be a linear superposition of transforms, with each transform acting on an input signal or on a component of an input signal. Each transform may act to focus one or more input signals to one or more output ports. A volume hologram may be made by various techniques, and from various materials. A transform function may be calculated by simulating the collision of a design input signal with a design output signal.
    Type: Grant
    Filed: June 13, 2006
    Date of Patent: May 29, 2007
    Assignee: LightSmyth Technologies Inc.
    Inventor: Thomas W. Mossberg
  • Patent number: 7221872
    Abstract: The invention discloses an on-line dispersion compensation device for a wavelength division optical transmission system. The device is consisted of two optical path selectors and at least one chirped grating fiber unit. The chirped grating fiber unit is consisted of two chirped grating fibers with same wavelength band and connected oppositely. In addition, the chirped grating fiber unit is serially connected between the appropriate ports of the two optical path selectors. The invention applies a structure that combines a chirped grating fiber unit with two optical path selectors. The structure is suitable to on-line dispersion compensation in a DWDM system and has low insertion loss. When only a few wavelengths need to be compensated, the structure makes dispersion compensation with low cost, low insertion loss and compensating a large dispersion value. For single channel or broadband compensation, the invention provides dispersion compensation without through OADM or MUX/DEMUX filtering.
    Type: Grant
    Filed: November 5, 2003
    Date of Patent: May 22, 2007
    Assignee: Huawei Technologies Co., Ltd.
    Inventors: Heliang Liu, Qianjin Xiong
  • Patent number: 7221873
    Abstract: The present invention relates to a network node that includes optical add/drop modules such that a module can be exchanged without disruption of the connections.
    Type: Grant
    Filed: February 8, 2000
    Date of Patent: May 22, 2007
    Inventors: Harald Bock, Patrick Leisching, Detlef Stoll
  • Patent number: 7209612
    Abstract: The invention relates to a planar lightwave circuit including a two stage optical filter for use in a bi-directional transceiver. A first stage includes a non-dispersive optical filter, which enables light within in a certain wavelength range, e.g. a signal channel from a laser source, to be launched onto an input/output waveguide, while light within another wavelength range, e.g. one or more detector channels, will be directed from the input/output waveguide to a second stage. The second stage includes a reflective diffraction grating with a higher resolution than the first stage providing passbands 2 to 5 times thinner than the first stage.
    Type: Grant
    Filed: June 1, 2005
    Date of Patent: April 24, 2007
    Assignee: Enablence Inc.
    Inventors: Ashok Balakrishnan, Serge Bidnyk, Matt Pearson
  • Patent number: 7206509
    Abstract: A method and apparatus are disclosed for temporally shifting one or more packets using wavelength selective delays. The header information associated with each packet, together with a routing algorithm, routing topology information and internal OPTR state, is used to route each packet to the appropriate destination channel and to make timing decisions. A wavelength server generates optical control wavelengths in response to the timing decisions. A generated optical control wavelength is used to adjust the wavelength of a given packet tray and thereby introduce a wavelength selective delay to the packet tray to align packet trays or to shift one or more packet trays to avoid a collision. The wavelength of the packet tray is converted to a control wavelength corresponding to an identified delay, irrespective of the initial channel upon which the packet tray was received. At the output stage of the packet tray router, the packet tray wavelength can be converted to any desired output channel wavelength.
    Type: Grant
    Filed: November 29, 2002
    Date of Patent: April 17, 2007
    Assignee: Lucent Technologies Inc.
    Inventor: Marc J. Beacken
  • Patent number: 7203422
    Abstract: In an optical wavelength division multiplexed access system, a center unit (OSU) and n optical network units (ONUs) are connected together via a wavelength splitter and optical fiber transmission lines, and downstream optical signals from the OSU to the ONUs and upstream optical signals from the ONUs to the OSU are transmitted in both directions, the wavelength spacing ??d (optical frequency spacing ?fd) of the downstream optical signals is set to twice or more the wavelength spacing ??u (optical frequency spacing ?fu) of the upstream optical signals, each ONU transmits an upstream optical signal whose optical spectral width is twice or more ??u (?fu), and the wavelength splitter spectrum slices the upstream signals transmitted from the ONUs into wavelengths (optical frequencies) whose optical spectral widths are mutually different within ??u (?fu), and wavelength-division multiplexes them and transmits to the OSU.
    Type: Grant
    Filed: December 22, 2003
    Date of Patent: April 10, 2007
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Jun-ichi Kani, Katsumi Iwatsuki
  • Patent number: 7199926
    Abstract: A diffraction grating device for splitting or coupling light beams permits the divergence of the light beams to be minimized easily. A first light beam is incident on a diffraction grating from the side thereof facing the inside of the device, and a second light beam is incident on the diffraction grating from the side thereof facing air. The diffraction grating transmits the first light beam by diffraction of the minus first order so that it travels in the reverse direction along the optical path of the second light beam before incidence, and transmits the second light beam by diffraction of the zero order. The second light beam, transmitted by diffraction of the zero order, spreads over a certain width of wavelengths, but does not diverge even after diffraction.
    Type: Grant
    Filed: March 28, 2005
    Date of Patent: April 3, 2007
    Assignee: Konica Minolta Holdings, Inc.
    Inventors: Shigeto Ohmori, Koujirou Sekine, Mitsuru Yokoyama
  • Patent number: 7190858
    Abstract: An optical time delay apparatus comprises: a multi-wavelength optical source; a diffractive element set imparting a wavelength-dependent delay on signals routed from the source to a 1×N optical switch; and N diffractive element sets routing signals from the 1×N switch to an output port. The optical propagation delay between the source and the output port varies according to the operational state of the source and the 1×N switch. A photodetector may receive the time-delayed signal at the output port.
    Type: Grant
    Filed: June 16, 2005
    Date of Patent: March 13, 2007
    Assignee: LightSmyth Technologies Inc
    Inventors: Christoph M. Greiner, Thomas W. Mossberg, Dmitri Iazikov
  • Patent number: 7190899
    Abstract: A system for providing high connectivity communications over a packet-switched optical ring network comprises a core optical ring having at least one node, the node being coupled to a subtending system by an optical crossbar switch, a source for generating a set of packets, a stacker for forming a first composite packet from the set of serial packets, the stacker coupled to the optical crossbar switch, and the stacker further coupled to the source for generating the set of packets, the first composite packet being parallel packets in a single photonic time slot, the first composite packet to be added to the core optical ring in a vacant photonic time slot via the optical crossbar switch, a second composite packet propagating on the core optical ring destined to be dropped at the node for further distribution on the subtending system via the optical crossbar switch, an unstacker for serializing the second composite packet dropped at the node, the unstacker coupled to the optical crossbar switch and a detector
    Type: Grant
    Filed: September 30, 2005
    Date of Patent: March 13, 2007
    Assignee: AT&T Corp.
    Inventors: Mikhail Boroditsky, Nicholas J. Frigo
  • Patent number: 7190859
    Abstract: A slab optical waveguide confines in one transverse dimension optical signals propagating in two dimensions therein, and has a set of diffractive elements collectively arranged so as to exhibit positional variation in amplitude, optical separation, or spatial phase. The diffractive elements are collectively arranged so as to apply a transfer function to an input optical signal to produce an output optical signal. The transfer function is determined at least in part by said positional variation in amplitude, optical separation, or spatial phase. The waveguide and diffractive elements are arranged so as to confine only one of the input and output optical signals to propagate in the waveguide so that the optical signal thus confined is successively incident on the diffractive elements, while the other optical signal propagates unconfined by the waveguide in a direction having a substantial component along the confined dimension of the waveguide.
    Type: Grant
    Filed: September 17, 2006
    Date of Patent: March 13, 2007
    Assignee: LightSmyth Technologies Inc
    Inventors: Christoph M. Greiner, Dmitri Iazikov, Thomas W. Mossberg
  • Patent number: 7190856
    Abstract: A reconfigurable add-drop multiplexer (R-OADM) comprises an array of channel waveguides coupling two groups of diffractive element sets on a slab waveguide. The channel waveguides include switchable reflectors or are coupled to other channel waveguides by optical switches. Switching a reflector to reflect or setting a switch to couple two waveguides results in a corresponding wavelength channel being added or dropped. Switching the reflector to transmit or setting the switch to uncouple the two waveguides allows the corresponding wavelength channel to pass through the R-OADM without being added or dropped.
    Type: Grant
    Filed: March 25, 2006
    Date of Patent: March 13, 2007
    Assignee: LightSmyth Technologies Inc
    Inventors: Dmitri Iazikov, Christoph M. Greiner, Thomas W. Mossberg
  • Patent number: 7187817
    Abstract: A single free-beam region for coupling electromagnetic radiation in and out is provided in order in the case of an AWG coupler for spectrally separating electromagnetic radiation to achieve a more stable thermal characteristic and a space-saving layout.
    Type: Grant
    Filed: March 8, 2002
    Date of Patent: March 6, 2007
    Assignee: Schott AG
    Inventors: Andrea Anton, Tobias Kälber, Detlef Wolff, Manfred Lohmeyer, Matthias Brinkmann, Klaus Gerstner
  • Patent number: 7184627
    Abstract: An optical wavelength grating coupler incorporating one or more distributed Bragg reflectors (DBR) or other reflective elements to enhance the coupling efficiency thereof. The grating coupler has a grating comprising a plurality of scattering elements adapted to scatter light along a portion of an optical path, and the one or more DBRs are positioned with respect to the grating such that light passing through the grating towards the substrate of the grating coupler is reflected back by DBRs toward the grating. The DBR comprises a multilayer stack of various materials and may be formed on the substrate of the grating coupler. The grating coupler may include a gas-filled cavity, where the cavity is formed by a conventional etching process and is used to reflect light toward the grating. The grating coupler may also incorporate an anti-reflection coating to reduce reflective loss on the surface of the grating.
    Type: Grant
    Filed: November 16, 2005
    Date of Patent: February 27, 2007
    Inventors: Lawrence C. Gunn, III, Thierry J. Pinguet, Maxime Jean Rattier
  • Patent number: 7182528
    Abstract: The present invention relates to a diffractive grating member and to an optical communication module. The optical communication module includes a semiconductor laser; a coupling optical system for coupling a light flux with a wavelength of ?1 emitted by the semiconductor laser to an optical fiber; and two light-receiving elements for receiving at least two light fluxes each having wavelengths ?2 and ?3 emitted from an end surface of the optical fiber. The coupling optical system has a diffractive structure, and the coupling optical system changes paths of light fluxes each having wavelengths ?1, ?2 and ?3 into relatively different directions such that the light flux with the wavelength ?1 emitted by the semiconductor laser enters into the optical fiber and each of the at least two light fluxes each having the wavelengths ?2 and ?3 enters into each of the two light-receiving elements.
    Type: Grant
    Filed: February 7, 2006
    Date of Patent: February 27, 2007
    Assignee: Konica Minolta Opto, Inc.
    Inventor: Nobuyoshi Mori
  • Patent number: 7177543
    Abstract: A method for routing optical packets using multiple wavelength labels includes converting optical packet address signals to a plurality of optical pulses having different time-deviated wavelengths by executing a first operation to impart a wavelength dependent delay time with respect to a plurality of optical pulses having different wavelengths at a same time axis position. When the optical pulses are transmitted along a predetermined optical path having dispersion the dispersion is compensated for by executing a second operation on the optical pulses corresponding to a reverse process of the operation to impart a wavelength dependent delay time. This second operation results in the generation of a plurality of optical pulses having different wavelengths at a given point on the time axis. The pulse signals thus generated are used to determine the packet transmission route.
    Type: Grant
    Filed: April 1, 2005
    Date of Patent: February 13, 2007
    Assignee: National Institute of Information and Communications Technology
    Inventors: Naoya Wada, Hiroaki Harai, Wataru Chujo, Fumito Kubota
  • Patent number: 7167650
    Abstract: A method and an apparatus are provided to demultiplex an optical signal having a plurality of channels at a predetermined channel spacing having demultiplexing means with a frequency spacing larger than the predetermined channel spacing for receiving the optical signal and for dividing the optical signal by wavelength into a plurality of wavelength streams broader than the predetermined channel spacing, time domain demultiplexing means for receiving one of the plurality of wavelength streams and for dividing the one of the plurality of wavelength streams into a plurality of time domain demultiplexed wavelength streams, and optical filtering means for demultiplexing one of the plurality of time domain demultiplexed wavelength streams into a single channel. Advantageously, splitting means are provided to split the optical signal into sub-signals before launching them into the demultiplexing means.
    Type: Grant
    Filed: June 25, 2001
    Date of Patent: January 23, 2007
    Assignee: JDS Uniphase Inc.
    Inventor: Mark Farries
  • Patent number: 7151635
    Abstract: The invention relates to a planar waveguide reflective diffraction grating for use in an optical device, such as a wavelength division multiplexer, providing an increased bandwidth over conventional planar waveguide reflection diffraction gratings while eliminating the polarization dependent loss (PDL) typically associated therewith. Accordingly, a low order (<3), high aspect ratio (>10) grating is provided with a very short side wall (less than the wavelength of the optical signal) for use with incident angles of less than 15°.
    Type: Grant
    Filed: October 25, 2004
    Date of Patent: December 19, 2006
    Assignee: Enablence, Inc.
    Inventors: Serge Bidnyk, Ashok Balakrishnan, Matt Pearson
  • Patent number: 7149387
    Abstract: The invention relates to a double-grating subtractive-dispersion optical channel multiplexer/demultiplexer for combining or separating optical channels and providing the output channels with a flat-top response. The FSR of the first grating is substantially equal to the channel spacing of the optical channels, such that the emission from the first grating achieves a cyclic offset of incidence angle into the second grating of the system.
    Type: Grant
    Filed: June 1, 2005
    Date of Patent: December 12, 2006
    Assignee: Enablence Inc.
    Inventors: Ashok Balakrishnan, Serge Bidnyk, Matt Pearson
  • Patent number: 7146107
    Abstract: A tunable dispersion compensator whose passband center wavelength changes when the amount of dispersion compensation is changed is suitably adjusted. The relationship between temperature for keeping the center wavelength constant and the amount of dispersion compensation is stored in advance. After controlling the amount of dispersion compensation to achieve best or optimum transmission quality, the amount of dispersion compensation is converted into temperature in accordance with the stored relationship and, based on that, the temperature is controlled to keep the center wavelength constant.
    Type: Grant
    Filed: December 18, 2003
    Date of Patent: December 5, 2006
    Assignee: Fujitsu Limited
    Inventors: Kentaro Nakamura, Hiroki Ooi, Tomoo Takahara
  • Patent number: 7139485
    Abstract: The invention relates to methods and arrangements for channel balancing of a wavelength division multiplexed optical signal. Channel balancing according to the invention is performed by using a resonator that provides a selection region in which a selected channel has a substantially increased poser density relative to channels out of resonance. The selected channel is attenuated a desired amount, i.e. a desired amount of power is removed therefrom, by adjusting the properties of the selection region. In a preferred embodiment, attenuation is achieved by adjusting the selection region such that destructive interference is obtained for the selected channel in a fiber carrying tile multiplexed optical signal.
    Type: Grant
    Filed: December 28, 2000
    Date of Patent: November 21, 2006
    Assignee: Proximion Fiber Systems AB
    Inventors: Adel Asseh, Simon Sandgren, Anders Henriksson, Mikael Bergman, Raoul Stubbe, Bengt Sahlgren, Ulf Öhlander
  • Patent number: 7136590
    Abstract: A system for matching a optical filter characteristic of a first filter tunable in wavelength with an optical first signal comprises a modulator for modulating at least a part of the first signal with a modulation signal before being applied to the first filter. An analyzing unit derives a control signal for tuning the first filter by analyzing the modulated first signal after passing the first filter in conjunction with the modulation signal.
    Type: Grant
    Filed: August 21, 2002
    Date of Patent: November 14, 2006
    Assignee: Agilent Technologies, Inc.
    Inventors: Ulrich Kallmann, Wolf Steffens
  • Patent number: 7136553
    Abstract: Provided are a tunable demultiplexer and a tunable laser, having an optical deflector in which a refractive index of a core layer of a deflection pattern region having a predetermined shape varies in response to an external electrical signal so that the optical deflector deflects incident light in the radial direction.
    Type: Grant
    Filed: June 24, 2005
    Date of Patent: November 14, 2006
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Oh Kee Kwon, Kang Ho Kim, Jong Hoi Kim, Hyun Soo Kim, Kwang Ryong Oh
  • Patent number: 7136589
    Abstract: A re-configurable optical add-drop multiplexer (OADM) (800) includes a first optical circulator (10), a second optical circulator (30), and a fiber Bragg grating (FBG) (20). The first optical circulator has a first circulator port (11), a second circulator port (12), and a third circulator port (13). The second optical circulator has the same structure as the first optical circulator. The FBG has a first state where it reflects an optical signal with a particular wavelength and passes all other wavelengths, and a second state where all the optical signals pass through it. The signal of the particular wavelength can thus be dropped from the optical signals by reflection of the FBG and output from the third circulator port of the first optical circulator, and a new signal of the same dropped wavelength can be added into the optical signals through a first circulator port (31) of the second optical circulator.
    Type: Grant
    Filed: July 5, 2002
    Date of Patent: November 14, 2006
    Assignee: Hon Hai Precision Ind. Co., Ltd
    Inventor: Ximin Zhao
  • Patent number: 7130542
    Abstract: An optical transmission system includes a number of corresponding modular multiplexing and demultiplexing units used in transmitting and receiving an optical signal respectively. Additionally, compensation components compensate for optical dispersion experienced by the optical signal. The modular multiplexing and demultiplexing units are assembled in a cascade fashion at the transmit side and the receive side of the optical transmission system, respectively. The dispersion compensation components share dispersion compensation fiber across the cascaded units.
    Type: Grant
    Filed: July 16, 2004
    Date of Patent: October 31, 2006
    Assignee: Corvis Corporation
    Inventors: Dalma Novak, Bo Pedersen, Quan-Zhen Wang
  • Patent number: 7127140
    Abstract: There is provided a fiber Bragg grating devise comprising an FBG mount that is constituted by sequentially stacking a temperature control plate, a base plate, and a mounting plate, and an SSFBG in which a plurality of FBG units of the same constitution and a plurality of phase modulation portions are alternately formed in the same optical fiber. The temperature control plate is constituted by a thermo module and a heat-insulating member. The base plate is fixed in contact with the upper face of the temperature control plate and the mounting plate is in contact with the upper face of the base plate in a state where the mounting plate is able to glide over the upper face of the base plate. The SSFBG is fixed to contact an FBG contact portion that is established on the upper face of the mounting plate.
    Type: Grant
    Filed: November 28, 2005
    Date of Patent: October 24, 2006
    Assignee: Oki Electric Industry Co., Ltd.
    Inventors: Shuko Kobayashi, Akihiko Nishiki
  • Patent number: 7123793
    Abstract: An optical architecture is provided comprising at least one broadband light source, a mod/mux unit, and a plurality of premises stations in communication with the mod/mux unit via an optical distribution hub. The mod/mux unit is configured to permit selective modulation of demultiplexed components of a target wavelength band of an optical signal, multiplex the selectively modulated optical signal, and direct the target wavelength band and a bypass wavelength band of the multiplexed optical signal to the optical distribution hub. The optical distribution hub comprises an arrayed waveguide grating configured to demultiplex the multiplexed optical signal and distribute respective distinct wavelength portions of the target wavelength band and respective distinct wavelength portions of the bypass wavelength band to respective ones of the premises stations.
    Type: Grant
    Filed: September 7, 2004
    Date of Patent: October 17, 2006
    Assignee: Optimer Photonics, Inc.
    Inventor: Richard W. Ridgway
  • Patent number: 7120334
    Abstract: An optical apparatus comprises a planar optical waveguide having at least two sets of diffractive elements. The planar optical waveguide substantially confines in at least one transverse spatial dimension optical signals propagating therein. The two diffractive element sets define an optical resonator that supports at least one resonant optical cavity mode. An optical signal in one of the resonant optical cavity modes is successively incident on the diffractive elements of each of the diffractive element sets.
    Type: Grant
    Filed: August 25, 2005
    Date of Patent: October 10, 2006
    Assignee: LightSmyth Technologies Inc
    Inventors: Christoph M. Greiner, Dmitri Iazikov, Thomas W. Mossberg
  • Patent number: 7113704
    Abstract: An input port of an add/drop node receives a plurality of optical channels. An add/drop port transmits a first drop channel of the plurality of channels when in a first channel mode and a second drop channel of the plurality of optical channels during a second channel mode. When the add/drop node is tuned from the first channel to the second channel, the output port transmits the plurality of channels spectrally located between the first channel and the second channel.
    Type: Grant
    Filed: November 28, 2000
    Date of Patent: September 26, 2006
    Assignee: Kotura, Inc.
    Inventor: Wenhua Lin
  • Patent number: 7113702
    Abstract: There is provided a WDM optical transmission system and transmission method that have excellent spectral efficiency. The WDM optical transmission system is provided with: an optical transmitting section having an optical transmitter that generates N wave (wherein N is an integer of 2 or greater) optical signals with an optical frequency spacing ?f [Hz] and modulated by a modulation bit rate B [bit/s] (wherein B/?f?1 [bit/s/Hz]) using a modulation device, and having a coupler that couples the optical signals; an optical receiving section provided with an optical DFT circuit of a sampling frequency ?f [Hz] that is equal to the optical frequency spacing; and a bit phase adjustor that makes bit phases of respective wavelength division multiplexed signals synchronous at an input of the optical DFT circuit.
    Type: Grant
    Filed: July 31, 2002
    Date of Patent: September 26, 2006
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Eiichi Yamada, Yuzo Yoshikuni, Hiroaki Sanjoh
  • Patent number: 7106512
    Abstract: A wavelength selective switching device and method for selectively transmitting optical signals based on wavelength utilizes diffraction to spatially separate the optical signals of different wavelengths such that the optical signal of a selected wavelength can be selectively transmitted. The wavelength selective switching device selectively rotates the polarization components of the optical signals such that the polarization states of the polarization components are the same in both incoming and outgoing directions at the diffraction grating. Thus, a diffraction grating with a high grating line frequency (e.g. greater than 900 grating lines per mm for signals in the 1550 nm wavelength range) can be used for diffracting the polarization components of the optical signals in both the incoming and outgoing directions.
    Type: Grant
    Filed: October 21, 2005
    Date of Patent: September 12, 2006
    Assignee: Avago Technologies Fiber IP (Singapore) Pte. Ltd.
    Inventors: Rene Helbing, Charles D. Hoke, Ken Nishimura
  • Patent number: 7103258
    Abstract: There is provided an attenuator device having a simple configuration and capable of selecting an output of beam of an arbitrary wavelength range from a plurality of output ports. The attenuator device comprises: a plurality of output fibers (1-3 and 1-5) having an end surface serving as an output port; discarding optical fibers (1-2 and 1-4) having an end surface serving as a discarding port and each arranged adjacently to the output optical fiber; a diffraction grating (5) which diffracts an incident beam into various directions according to the wavelength thereof; and a micro mirror array (7) which adjusts the output direction of the diffracted beam for each of the wavelength ranges output from the diffraction grating (5). The micro mirror array (7) adjusts the output direction of the diffracted beam so that a part of the diffracted beam may be output to the output port while the rest being output to the discarding port.
    Type: Grant
    Filed: October 24, 2005
    Date of Patent: September 5, 2006
    Assignee: Nikon Corporation
    Inventor: Atsushi Katsunuma
  • Patent number: 7099086
    Abstract: An improvement in a wavelength division multiplexer and/or a dense wavelength division multiplexer (WDM/DWDM) is achieved by incorporating an electronically reconfigurable diffraction grating (108). The introduction of the electronically reconfigurable diffraction grating (108), which is typically fabricated using MEMS (microelectromechanical systems) technology, improves the compact design, durability, and dynamic functionality of the WDM/DWDM system.
    Type: Grant
    Filed: December 5, 2000
    Date of Patent: August 29, 2006
    Assignee: InterScience, Inc.
    Inventor: Mikhail A. Gutin
  • Patent number: 7092634
    Abstract: Disclosed herein is a bidirectional wavelength division multiplexed self-healing ring network. The ring network includes a central office and a plurality of remote nodes. Two optical fibers each connect the central office and the remote nodes in a ring form to allow optical signals to be bidirectionally received and transmitted between the central office and the remote nodes. One of the two optical fibers is a drop fiber for transmitting optical signals from the central office to the remote nodes, while the other is an add fiber for transmitting optical signals from the remote nodes to the central office.
    Type: Grant
    Filed: May 31, 2002
    Date of Patent: August 15, 2006
    Assignee: Korea Advanced Institute of Science and Technology
    Inventors: Chang Hee Lee, Sung Bum Park
  • Patent number: 7092631
    Abstract: A system for providing high connectivity communications over a packet-switched optical ring network comprises a core optical ring having at least one node, the node being coupled to a subtending system by an optical crossbar switch, a source for generating a set of packets, a stacker for forming a first composite packet from the set of serial packets, the stacker coupled to the optical crossbar switch, and the stacker further coupled to the source for generating the set of packets, the first composite packet being parallel packets in a single photonic time slot, the first composite packet to be added to the core optical ring in a vacant photonic time slot via the optical crossbar switch, a second composite packet propagating on the core optical ring destined to be dropped at the node for further distribution on the subtending system via the optical crossbar switch, an unstacker for serializing the second composite packet dropped at the node, the unstacker coupled to the optical crossbar switch and a detector
    Type: Grant
    Filed: October 11, 2001
    Date of Patent: August 15, 2006
    Assignee: AT&T Corp.
    Inventors: Mikhail Boroditsky, Nicholas J. Frigo
  • Patent number: 7085496
    Abstract: An add/drop node for an optical network comprises a passive splitter to split an ingress signal from the network into a first ingress signal and a second ingress signal. A first amplified splitter stages module is operable to passively split and amplify the first ingress signal into a plurality of drop signals. A filter module is operable to filter the second ingress signal to provide a filtered pass-through signal. A second amplified splitter stages module is operable to passively combine a plurality of add signals into a combined add signal and to combine the combined add signal with the filtered pass-through signal to create an egress signal forwardable to the network.
    Type: Grant
    Filed: May 30, 2002
    Date of Patent: August 1, 2006
    Assignee: Fujitsu Limited
    Inventors: Susumu Kinoshita, Remi Pecqueur, Cechan Tian
  • Patent number: 7085495
    Abstract: A system and method for simultaneous delivery of a plurality of independent blocks of 500 MHz digital broadcast television services, stacking a plurality of RF blocks on a plurality of spectrally sliced WDM optical bands.
    Type: Grant
    Filed: July 30, 2001
    Date of Patent: August 1, 2006
    Assignee: AT&T Corp.
    Inventors: Martin Birk, Patrick P. Iannone, Kenneth C. Reichmann, Nicholas J. Frigo, Cedric F. Lam
  • Patent number: 7079770
    Abstract: A system and apparatus for dropping and adding optical data streams in an optical communication network uses a photonic switching fabric for dropping but not adding optical data streams, and uses a combiner external to this photonic switching fabric for combining passed optical data streams from the photonic switching fabric together with added optical data streams. The added optical data streams are not limited to the wavelengths of the dropped optical data streams. The photonic switching fabric may be a Micro Electro Mechanical System (MEMS) that uses single-sided mirrors configurable to drop but not add optical data streams.
    Type: Grant
    Filed: December 19, 2000
    Date of Patent: July 18, 2006
    Assignee: Nortel Networks Limited
    Inventor: Bruce A. Schofield
  • Patent number: 7079728
    Abstract: A wavelength multiplexing processing apparatus for use with a wavelength division multiplexing system is disclosed which uses a single AWG to achieve reduction in cost, size and loss. The wavelength multiplexing processing apparatus includes a waveguide device wherein a plurality of incoming and outgoing waveguides, a first slab waveguide and a plurality of channel waveguides are formed on a substrate, a mirror array device and a lens device. The plane direction angles of reflecting mirrors which reflect optical signal components incoming thereto are set so that reflected light of an optical signal component incoming from one of the plural incoming and outgoing waveguides may go out from one of the plural incoming and outgoing waveguides.
    Type: Grant
    Filed: December 30, 2003
    Date of Patent: July 18, 2006
    Assignee: Fujitsu Limited
    Inventors: Goji Nakagawa, Hideyuki Miyata