Patents by Inventor Xia Xu

Xia Xu has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20080104139
    Abstract: Embodiments include methods, apparatus, and systems for managing snapshots in storage systems. One method includes logically linking a plurality of snapshots to a logical disk in a storage network; and splitting the snapshots from the logical disk to form a snapshot tree that includes the snapshots split from the logical disk.
    Type: Application
    Filed: October 26, 2006
    Publication date: May 1, 2008
    Inventors: Xia Xu, Aaron Lindemann
  • Patent number: 7317535
    Abstract: A spectroscopic method and system for the spectral analysis of an optical signal directed to a wavelength dispersive component having two interleaved dispersive devices. For a single wavelength, the optical signal exiting the interleaved dispersive devices includes two wavefronts generally disposed at an angle to one another and producing an interference pattern. The interference pattern is detected and subsequently analyzed via a Fourier transform to produce the optical spectrum of the input beam. The method and system are applicable in a planar waveguide environment, in reflection and transmission geometries.
    Type: Grant
    Filed: September 9, 2005
    Date of Patent: January 8, 2008
    Assignee: National Research Council of Canada
    Inventors: Pavel Cheben, Ian Powell, Siegfried Janz, Dan-Xia Xu
  • Publication number: 20070245104
    Abstract: Exemplary storage network architectures, data architectures, and methods for data restore operation are disclosed. In one embodiment, a storage device comprises a processor, a memory module communicatively connected to the processor, and logic instructions in the memory module which, when executed by the processor, configure the processor to receive a signal that identifies a source volume and a first target snapshot that represents a point in time copy of the source volume, update metadata to define an restore relationship between the first target snapshot and the source volume, execute a background copy process between the first target snapshot and the source volume, and manage input/output operations during the background copy process to permit input/output operations to the source volume during the background copy process.
    Type: Application
    Filed: April 14, 2006
    Publication date: October 18, 2007
    Inventors: Aaron Lindemann, Xia Xu, Rodger Daniels, Lee Nelson
  • Patent number: 7272276
    Abstract: An optical performance monitor for measuring the performance of optical networks has an echelle grating for demultiplexing an input beam into a plurality of wavelengths that are focused onto an array of divided output waveguides. Each divided output waveguide is positioned to receive a corresponding demultiplexed wavelength from the echelle grating or other waveguide multiplexer device. The divided output waveguides laterally separate the corresponding demultiplexed wavelength into a first and second portions. A detector array is positioned to receive the respective portions of the demultiplexed wavelengths and by comparing their relative intensity it is possible to detect any drift in the nominal wavelengths of the channels.
    Type: Grant
    Filed: November 8, 2001
    Date of Patent: September 18, 2007
    Assignee: Enablence Inc.
    Inventors: Matt Pearson, Lynden Erickson, John Miller, Siegfried Janz, Dan-Xia Xu, Pavel Cheben, Andre Delage, Boris Lamontagne, Sylvain Charbonneau
  • Publication number: 20070207537
    Abstract: A cell culture plate for perfused cell or tissue culture comprises one or more wells. The wells are formed from a biocompatible gas permeable polymer. Means are provided to perfuse each well.
    Type: Application
    Filed: March 20, 2007
    Publication date: September 6, 2007
    Inventors: Zhanfeng Cui, Min-Hsein Wu, Xia Xu
  • Patent number: 7194177
    Abstract: In order to make a photonic device incorporating a waveguide, a waveguide is formed with a predetermined geometry. Birefringence is then controlled by determining the amount of stress induced within the waveguide.
    Type: Grant
    Filed: September 29, 2004
    Date of Patent: March 20, 2007
    Assignee: National Research Council of Canada
    Inventors: Dan-Xia Xu, Pavel Cheben, Dan Dalacu, Siegfried Janz
  • Publication number: 20070004045
    Abstract: Mass-spectrometry based methods of analyzing estrogens and other steroids from biological samples are disclosed herein. Further disclosed are methods of detecting the presence of illegal steroids in a mammal. Methods of detecting a disease state or condition or elevated risk of a disease state or condition in a mammal are also disclosed. Also disclosed are kits for use in a method for detecting and/or quantifying one or more steroids in a sample by mass spectrometry.
    Type: Application
    Filed: June 7, 2006
    Publication date: January 4, 2007
    Inventors: Xia Xu, Timothy Veenstra, Larry Keefer, Regina Ziegler
  • Patent number: 7132656
    Abstract: According to this invention, silicon-based photodetectors using waveguides formed with silicide regions can have high speed and high efficiency for near IR applications. Utilizing the unique properties of silicides, the proposed method provides a simple and elegant way to implement a photodetector design in which photogenerated carriers travel perpendicular to the direction of light propagation. Therefore, the speed and quantum efficiency of the photodetector may be optimized independently. This device configuration may be implemented in one of the two approaches: (a) waveguides formed through surface silicidation of a silicon-based layer of a substrate (b) waveguides formed through silicidation of ridge waveguide side-walls of a silicon-based layer of a substrate; The use of mature silicon technology promises low cost of production and other benefits.
    Type: Grant
    Filed: September 20, 2004
    Date of Patent: November 7, 2006
    Assignee: National Research Council of Canada
    Inventors: Dan-Xia Xu, Siegfried Janz
  • Publication number: 20060209411
    Abstract: An Echelle grating has alternate first (1a) and second (1b) sets of facets (1). The first set of facets (1a) is operative to reflect incident light (4) for diffraction and the second set of facets (1b) extends between adjacent facets of the first set (1a). Only the first set of facets (1a) is metallized to enhance reflection. The second set of facets (1b) is left unmetallized. This configuration reduces polarization dependent loss (PDL).
    Type: Application
    Filed: November 26, 2002
    Publication date: September 21, 2006
    Inventors: Andre Delage, Boris Lamontagne, Kokou Dossou, Siegfried Janz, Pavel Cheben, Lynden Erickson, Dan-Xia Xu, Sylvain Charbonneau
  • Publication number: 20060055935
    Abstract: A spectroscopic method and system for the spectral analysis of an optical signal directed to a wavelength dispersive component having two interleaved dispersive devices. For a single wavelength, the optical signal exiting the interleaved dispersive devices includes two wavefronts generally disposed at an angle to one another and producing an interference pattern. The interference pattern is detected and subsequently analyzed via a Fourier transform to produce the optical spectrum of the input beam. The method and system are applicable in a planar waveguide environment, in reflection and transmission geometries.
    Type: Application
    Filed: September 9, 2005
    Publication date: March 16, 2006
    Inventors: Pavel Cheben, Ian Powell, Siegfried Janz, Dan-Xia Xu
  • Publication number: 20050196114
    Abstract: In order to make a photonic device incorporating a waveguide, a waveguide is formed with a predetermined geometry. Birefringence is then controlled by determining the amount of stress induced within the waveguide.
    Type: Application
    Filed: September 29, 2004
    Publication date: September 8, 2005
    Applicant: National Research Council of Canada
    Inventors: Dan-Xia Xu, Pavel Cheben, Dan Dalacu, Siegfried Janz
  • Publication number: 20050181514
    Abstract: Methods for enhancing detection by mass spectroscopy (MS) and/or chromatographic separability of carbonyl-containing compounds such as steroids are disclosed. Reaction of a carbonyl compound with a sulfonhydrazide compound provides a sulfonhydrazone with enhanced ionization efficiency during the electrospray ionization process. In a particularly disclosed embodiment, derivatization of catechol estrogens with p-toluenesulfonhydrazide enhances both detection by atmospheric pressure ionization-MS (API-MS), such as electron spray ionization-MS (ESI-MS) and separation by liquid chromatography (such as HPLC) under reverse phase conditions. In yet other embodiments, the sulfonhydrazone is further reacted with a sulfonyl halide under alkaline conditions to derivatize hydroxyl groups in the compound. Prior formation of the sulfonhydrazide derivative protects the carbonyl bond of the compound during subsequent alkaline reaction with the sulfonyl halide.
    Type: Application
    Filed: April 15, 2003
    Publication date: August 18, 2005
    Inventors: Xia Xu, Regina Ziegler, David Waterhouse, Joseph Saavedra, Larry Keefer
  • Publication number: 20050141808
    Abstract: The multichannel waveguide device includes an array of waveguides located in a plane. Each waveguide channel has a redirecting element for redirecting a guided wave out of said plane, or vice versa. The redirecting elements are staggered in the direction of the waveguides so as to transform a one-dimensional array of in-plane waves into a two-dimensional array of out-of-plane waves, or vice versa.
    Type: Application
    Filed: December 21, 2004
    Publication date: June 30, 2005
    Applicant: National Research Council of Canada
    Inventors: Pavel Cheben, Siegfried Janz, Boris Lamontagne, Dan-Xia Xu
  • Publication number: 20050029455
    Abstract: According to this invention, silicon-based photodetectors using waveguides formed with silicide regions can have high speed and high efficiency for near IR applications. Utilizing the unique properties of silicides, the proposed method provides a simple and elegant way to implement a photodetector design in which photogenerated carriers travel perpendicular to the direction of light propagation. Therefore, the speed and quantum efficiency of the photodetector may be optimized independently. This device configuration may be implemented in one of the two approaches: (a) waveguides formed through surface silicidation of a silicon-based layer of a substrate (b) waveguides formed through silicidation of ridge waveguide side-walls of a silicon-based layer of a substrate; The use of mature silicon technology promises low cost of production and other benefits.
    Type: Application
    Filed: September 20, 2004
    Publication date: February 10, 2005
    Inventors: Dan-Xia Xu, Siegfried Janz
  • Publication number: 20040240063
    Abstract: A method is desribed for controlling the pass band of an optical device wherein a phase mask is introduced to modify the shaped of an image produced by the photonic device.
    Type: Application
    Filed: November 28, 2003
    Publication date: December 2, 2004
    Inventors: Andre Delage, Muthukumaran Packirisamy, Siegfried Janz, Lynden Erickson, Dan-Xia Xu, Pavel Cheben, Boris Lamontage, Sylvain Charbonneau
  • Patent number: 6815245
    Abstract: According to this invention, silicon-based photodetectors using waveguides formed with silicide regions can have high speed and high efficiency for near IR applications. Utilizing the unique properties of suicides, the proposed method provides a simple and elegant way to implement a photodetector design in which photogenerated carriers travel perpendicular to the direction of light propagation. Therefore, the speed and quantum efficiency of the photodetector may be optimized independently. This device configuration may be implemented in one of the two approaches: (a) waveguides formed through surface silicidation of a silicon-based layer of a substrate (b) waveguides formed through silicidation of ridge waveguide side-walls of a silicon-based layer of a substrate; The use of mature silicon technology promises low cost of production and other benefits.
    Type: Grant
    Filed: December 19, 2001
    Date of Patent: November 9, 2004
    Assignee: National Research Council of Canada
    Inventors: Dan-Xia Xu, Siegfried Janz
  • Publication number: 20040151429
    Abstract: Disclosed is an optical double pass equalizer for equalizing a wavelength division multiplexed (WDM) signal. The equalizer comprises a multiplexer/demultiplexer and multiple variable optical attenuators (VOAs) integrated on a single monolithic chip. The WDM signal is demultiplexed into individual wavelength channels by the multiplexer/demultiplexer and each wavelength channel is equalized by a corresponding VOA. The equalized wavelength channels are then multiplexed into an equalized WDM signal by the multiplexer/demultiplexer. This provides several advantages, including a reduction in required assembly and assembly cost, as well as an improved dynamic range in attenuation level or alternatively a reduction in power consumption for a fix attenuation level compared to a single pass VOA unit.
    Type: Application
    Filed: November 28, 2003
    Publication date: August 5, 2004
    Inventors: Siegfried Janz, Dan-Xia Xu, Pavel Cheben, Andre Delage, Lynden Erickson, Boris Lamontagne, Sylvain Charbonneau
  • Publication number: 20040151459
    Abstract: The method consists of creating a compensating region within the slab waveguide region, with effective TE and TM mode refractive indices of the compensating region higher than those of the original slab waveguide. Such change in refractive indices is achieved by deposition of an over-layer on the compensating region.
    Type: Application
    Filed: November 28, 2003
    Publication date: August 5, 2004
    Inventors: Pavel Cheben, Siegfried Janz, Dan-Xia Xu, Andre Delage, Lynden Erickson, Boris Lamontage, Sylvain Charbonneau
  • Publication number: 20030068113
    Abstract: A method is disclosed for polarization birefringence compensation in a photonic device with a slab waveguide having a core. A compensator region is formed in the slab waveguide to minimize the wavelength shift between light of different polarizations. A thin capping layer, typically of silicon nitride, having a higher refractive index than the core, is formed on the compensator region to increase the birefringence contrast between the compensator region and the planar waveguide.
    Type: Application
    Filed: January 25, 2002
    Publication date: April 10, 2003
    Inventors: Siegfried Janz, Dan-Xia Xu, Pavel Cheben, Andre Delage, Lynden Erickson, Boris Lamontagne, Sylvain Charbonneau
  • Publication number: 20030063849
    Abstract: A method is disclosed for polarization birefringence compensation in a photonic device with a slab waveguide having a core. A compensator region is formed in the slab waveguide to minimize the wavelength shift between light of different polarizations. A thin capping layer, typically of silicon nitride, having a higher refractive index than the core is formed on the compensator region to increase the birefringence contrast between the compensator region and the planar waveguide.
    Type: Application
    Filed: November 8, 2001
    Publication date: April 3, 2003
    Inventors: Siegfried Janz, Dan-Xia Xu, Pavel Cheben, Andre Delage, Lynden Erickson, Boris Lamontagne, Sylvain Charbonneau