Patents by Inventor Xuehua Wu

Xuehua Wu 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: 20080219663
    Abstract: An optical switching device for wavelength divisional multiplexed signals uses cascaded arrays of optical steering devices for 1×N routing of WDM optical signals, where N=4, 8, 16, etc. Two cascaded arrays provide 1×4 switching; three cascaded arrays provide 1×8 switching; and so on. Each array is configured with independently controlled optical steering devices so that each wavelength channel of the WDM signal may be routed to any of N output ports. The optical steering devices may be micro-mirrors, liquid crystal-based polarization modulators, or a combination of both. By incorporating cascaded optical steering devices into a single WDM switching device, cost effective 1×N switching of WDM optical signals may be realized.
    Type: Application
    Filed: January 15, 2008
    Publication date: September 11, 2008
    Inventors: Haijun Yuan, Xuehua Wu, Christopher Lin, Giovanni Barbarossa
  • Patent number: 7340130
    Abstract: The present invention describes a structure and method for a multi-ports WDM device for compensating the filter distortion while reducing insertion loss. The multi-ports WDM device comprises a 4-fiber collimator having a grin lens and a 2-fiber collimator having a lens where the focal plane of the second lens is shorter than the focal plane of the first grin lens Ands with aspheric surface. When a light signal travels through the first lens in the 4-fiber collimator to a filter, the film on the filter causes distortion to the light signal resulting in a large insertion loss. To compensate for the insertion loss, the lens on the 2-fiber collimator has a aspheric function and a shorter focal plane than the grin lens on the 4-fiber collimator. The type of grin lens used in the 4-fiber collimator is different than the lens used in the 2-fiber collimator. Effectively, the lens in the 2-fiber collimator operates to de-focus a light signal relative to the grin lens in the 4-fiber collimator.
    Type: Grant
    Filed: October 11, 2005
    Date of Patent: March 4, 2008
    Assignee: Avanex Corporation
    Inventors: Xuehua Wu, Mingjun Zhao, John Feng
  • Publication number: 20080037932
    Abstract: An optical switch with a compact form factor includes a multiple-fiber collimator and an angle tuning element for deflecting an optical beam from an input fiber into one of at least two output fibers. The angle tuning element may be provided between a pair of coaxially-aligned collimators, one of which is the multiple-fiber collimator. Alternatively, the angle tuning element may be provided between the multiple-fiber collimator and a reflective surface, so that only one collimator is required and the optical switch may be designed to have its input and output ports on the same side.
    Type: Application
    Filed: October 19, 2007
    Publication date: February 14, 2008
    Inventors: Ming Cai, Xuehua Wu, Giovanni Barbarossa
  • Patent number: 7286730
    Abstract: An optical switch with a compact form factor includes a multiple-fiber collimator and an angle tuning element for deflecting an optical beam from an input fiber into one of at least two output fibers. The angle tuning element may be provided between a pair of coaxially-aligned collimators, one of which is the multiple-fiber collimator. Alternatively, the angle tuning element may be provided between the multiple-fiber collimator and a reflective surface, so that only one collimator is required and the optical switch may be designed to have its input and output ports on the same side.
    Type: Grant
    Filed: March 15, 2006
    Date of Patent: October 23, 2007
    Assignee: Avanex Corporation
    Inventors: Ming Cai, Xuehua Wu, Giovanni Barbarossa
  • Publication number: 20070217735
    Abstract: An optical switch with a compact form factor includes a multiple-fiber collimator and an angle tuning element for deflecting an optical beam from an input fiber into one of at least two output fibers. The angle tuning element may be provided between a pair of coaxially-aligned collimators, one of which is the multiple-fiber collimator. Alternatively, the angle tuning element may be provided between the multiple-fiber collimator and a reflective surface, so that only one collimator is required and the optical switch may be designed to have its input and output ports on the same side.
    Type: Application
    Filed: March 15, 2006
    Publication date: September 20, 2007
    Inventors: Ming Cai, Xuehua Wu, Giovanni Barbarossa
  • Patent number: 7221818
    Abstract: The present invention relates to an optical switch. The optical switch includes at least two binary control elements movable between a first and second position. The binary control elements include an at least one angle tuning element for adjusting the pathway of an optical signal. With a binary control element in the first position, the angle tuning element is able to adjust the pathway of an optical signal. With the binary control element in a second position, the angle tuning element is not able to adjust the optical pathway of an optical signal. The optical switch of the present invention can also concurrently switch multiple optical signals in parallel.
    Type: Grant
    Filed: March 1, 2005
    Date of Patent: May 22, 2007
    Assignee: Avanex Corporation
    Inventors: Ming Cai, Xuehua Wu, Giovanni Barbarossa
  • Patent number: 7171073
    Abstract: The present invention describes a structure and method for a multi-ports WDM device for compensating the filter distortion while reducing insertion loss. The multi-ports WDM device comprises a 4-fiber collimator having a grin lens and a 2-fiber collimator having a lens where the focal plane of the second lens is shorter than the focal plane of the first grin lens Ands with aspheric surface. When a light signal travels through the first lens in the 4-fiber collimator to a filter, the film on the filter causes distortion to the light signal resulting in a large insertion loss. To compensate for the insertion loss, the lens on the 2-fiber collimator has a aspheric function and a shorter focal plane than the grin lens on the 4-fiber collimator. The type of grin lens used in the 4-fiber collimator is different than the lens used in the 2-fiber collimator. Effectively, the lens in the 2-fiber collimator operates to de-focus a light signal relative to the grin lens in the 4-fiber collimator.
    Type: Grant
    Filed: October 11, 2005
    Date of Patent: January 30, 2007
    Assignee: Avanex Corporation
    Inventors: Xuehua Wu, Mingjun Zhao, John Feng
  • Patent number: 7158697
    Abstract: An optical apparatus functioning either as a multiplexer or a demultiplexer, including: a first polarization beam splitter (PBS); a second PBS optically coupled to the first PBS along an axis of the apparatus; a half-wave plate optically coupled between the first and second PBS; a common optical port optically coupled to the first PBS at a face intersecting the axis; a first non-common optical port optically coupled to the first PBS at a face not intersecting the axis; a second non-common optical port optically coupled to the second PBS; and a reflection interferometer optically coupled to the second PBS. The apparatus provides the benefits of using the reflection interferometer, but does not require paired reflection interferometers or Faraday rotators.
    Type: Grant
    Filed: April 28, 2003
    Date of Patent: January 2, 2007
    Assignee: Avanex Corporation
    Inventors: Xuehua Wu, YueZhong Feng, Xixiang Chen, Giovanni Barbarossa, Simon X. F. Cao
  • Publication number: 20060198574
    Abstract: The present invention relates to an optical switch. The optical switch includes at least two binary control elements movable between a first and second position. The binary control elements include an at least one angle tuning element for adjusting the pathway of an optical signal. With a binary control element in the first position, the angle tuning element is able to adjust the pathway of an optical signal. With the binary control element in a second position, the angle tuning element is not able to adjust the optical pathway of an optical signal. The optical switch of the present invention can also concurrently switch multiple optical signals in parallel.
    Type: Application
    Filed: March 1, 2005
    Publication date: September 7, 2006
    Inventors: Ming Cai, Xuehua Wu, Giovanni Barbarossa
  • Publication number: 20040151425
    Abstract: An optical apparatus functioning either as a multiplexer or a demultiplexer, including: a first polarization beam splitter (PBS); a second PBS optically coupled to the first PBS along an axis of the apparatus; a half-wave plate optically coupled between the first and second PBS; a common optical port optically coupled to the first PBS at a face intersecting the axis; a first non-common optical port optically coupled to the first PBS at a face not intersecting the axis; a second non-common optical port optically coupled to the second PBS; and a reflection interferometer optically coupled to the second PBS. The apparatus provides the benefits of using the reflection interferometer, but does not require paired reflection interferometers or Faraday rotators.
    Type: Application
    Filed: April 28, 2003
    Publication date: August 5, 2004
    Inventors: Xuehua Wu, YueZhong Feng, Xixiang Chen, Giovanni Barbarossa, Simon X.F. Cao
  • Patent number: 6428719
    Abstract: Write head coils for magnetic disk systems are commonly formed through electroplating onto a seed layer in the presence of a photoresist mask. It is then necessary to remove the seed layer everywhere except under the coil itself. The present invention achieves this through etching in a solution of ammonium persulfate to which has been added the complexing agent 1,4,8,11 tetraazundecane. This suppresses the reduction of Cu++ to Cu, thereby increasing the dissolution rate of copper while decreasing that of nickel-iron. Two ways of implementing this are described—adding the complexing agent directly to the ammonium persulfate and introducing the 1,4,8,11 tetraazundecane through a dipping process that precedes conventional etching in the ammonium persulfate.
    Type: Grant
    Filed: January 19, 2000
    Date of Patent: August 6, 2002
    Assignee: Headway Technologies, Inc.
    Inventors: Xuehua Wu, Wensen Li, Si-Tuan Lam, Henry C. Chang, Kochan Ju, Jei-Wei Chang
  • Patent number: 6395458
    Abstract: The problem of copper corrosion that occurs in the presence of strong alkaline developing solutions during photo rework has been overcome by protecting all exposed copper bearing surfaces from attack. Two ways of achieving this are described. In the first method, benzotriazole (BTA) is added to the developing solution which is then used in the normal way, developing time being unaffected by this modification. In the second method, the surface that is to receive the photoresist is first given a dip in a solution of BTA, following which the photoresist is immediately applied and processing, including proceeds as normal. For both methods the result is the elimination of all copper corrosion during development.
    Type: Grant
    Filed: January 8, 2001
    Date of Patent: May 28, 2002
    Assignee: Headway Technologies, Inc.
    Inventors: Xuehua Wu, Yi-Chun Liu, Jei-Wei Chang, Kochan Ju
  • Patent number: 6387599
    Abstract: The problem of copper corrosion that occurs in the presence of strong alkaline developing solutions during photo rework has been overcome by protecting all exposed copper bearing surfaces from attack. Two ways of achieving this are described. In the first method, benzotriazole (BTA) is added to the developing solution which is then used in the normal way, developing time being unaffected by this modification. In the second method, the surface that is to receive the photoresist is first given a dip in a solution of BTA, following which the photoresist is immediately applied and processing, including development, proceeds as normal. For both methods the result is the elimination of all copper corrosion during development.
    Type: Grant
    Filed: January 8, 2001
    Date of Patent: May 14, 2002
    Assignee: Headway Technologies, Inc.
    Inventors: Xuehua Wu, Yi-Chun Liu, Jei-Wei Chang, Kochan Ju
  • Patent number: 6291138
    Abstract: A method for forming a plated layer. There is first provided a substrate. There is then formed over the substrate a masking frame employed for masking frame plating a masking frame plated layer within the masking frame, where the masking frame is fabricated to provide an overhang of an upper portion of the masking frame spaced further from the substrate with respect to a lower portion of the masking frame spaced closer to the substrate. Finally, there is then plated the masking frame plated layer within the masking frame. The method is useful for forming masking frame plated magnetic pole tip stack layers with enhanced planarity dimensional control within magnetic transducer elements.
    Type: Grant
    Filed: July 23, 1999
    Date of Patent: September 18, 2001
    Assignee: Headway Technologies, Inc.
    Inventors: Xuehua Wu, Yi-Chun Liu, Yining Hu, Jei-Wei Chang, Kochan Ju
  • Publication number: 20010008745
    Abstract: The problem of copper corrosion that occurs in the presence of strong alkaline developing solutions during photo rework has been overcome by protecting all exposed copper bearing surfaces from attack. Two ways of achieving this are described. In the first method, benzotriazole (BTA) is added to the developing solution which is then used in the normal way, developing time being unaffected by this modification. In the second method, the surface that is to receive the photoresist is first given a dip in a solution of BTA, following which the photoresist is immediately applied and processing, including development, proceeds as normal. For both methods the result is the elimination of all copper corrosion during development.
    Type: Application
    Filed: January 8, 2001
    Publication date: July 19, 2001
    Applicant: HEADWAY TECHNOLOGIES, INC.
    Inventors: Xuehua Wu, Yi-Chun Liu, Jei-Wei Chang, Kochan Ju
  • Publication number: 20010008744
    Abstract: The problem of copper corrosion that occurs in the presence of strong alkaline developing solutions during photo rework has been overcome by protecting all exposed copper bearing surfaces from attack. Two ways of achieving this are described. In the first method, benzotriazole (BTA) is added to the developing solution which is then used in the normal way, developing time being unaffected by this modification. In the second method, the surface that is to receive the photoresist is first given a dip in a solution of BTA, following which the photoresist is immediately applied and processing, including development, proceeds as normal. For both methods the result is the elimination of all copper corrosion during development.
    Type: Application
    Filed: January 8, 2001
    Publication date: July 19, 2001
    Applicant: HEADWAY TECHNOLOGIES, INC.
    Inventors: Xuehua Wu, Yi-Chun Liu, Jei-Wei Chang, Kochan Ju
  • Publication number: 20010008743
    Abstract: The problem of copper corrosion that occurs in the presence of strong alkaline developing solutions during photo rework has been overcome by protecting all exposed copper bearing surfaces from attack. Two ways of achieving this are described. In the first method, benzotriazole (BTA) is added to the developing solution which is then used in the normal way, developing time being unaffected by this modification. In the second method, the surface that is to receive the photoresist is first given a dip in a solution of BTA, following which the photoresist is immediately applied and processing, including development, proceeds as normal. For both methods the result is the elimination of all copper corrosion during development.
    Type: Application
    Filed: January 8, 2001
    Publication date: July 19, 2001
    Applicant: HEADWAY TECHNOLOGIES, INC.
    Inventors: Xuehua Wu, Yi-Chun Liu, Jei-Wei Chang, Kochan Ju
  • Patent number: 6239948
    Abstract: A non-magnetic conductor material, a magnetic transducer element having formed therein a non-magnetic conductor layer formed of the non-magnetic conductor material and a method for forming a magnetic transducer element having formed therein the non-magnetic conductor layer formed of the non-magnetic conductor material. The non-magnetic conductor material comprises an alloy comprising nickel and at least one non-magnetic conductor metal selected from the group consisting of copper at a weight percent of from about 45 to about 90, zinc at a weight percent of from about 20 to about 75, cadmium at a weight percent of from about 35 to about 85, platinum at a weight percent of from about 55 to about 90 and palladium at a weight percent of from about 75 to about 95. The non-magnetic conductor material contemplates the magnetic transducer element and the method for forming the magnetic transducer element.
    Type: Grant
    Filed: July 23, 1999
    Date of Patent: May 29, 2001
    Assignee: Headway Technologies, Inc.
    Inventors: Xuehua Wu, Kochan Ju, Jei-Wei Chang
  • Patent number: 6218080
    Abstract: It has been observed that plated structures grown inside molds for small objects, such as a gap structure in a magnetic read head, often have curved rather than planar surfaces. This problem has been overcome as follows. Prior to laying down photoresist for the mold, a layer of copper is deposited on the substrate on which the head structure is to be grown (normally the shared pole). After the photoresist is patterned to form the mold, all exposed copper is selectively removed from the substrate a key feature being that the copper is over-etched so that some undercutting of the photoresist occurs. Then, when the layers making up the gap structure are electrodeposited inside the mold they grow away from the substrate as planar surfaces.
    Type: Grant
    Filed: March 6, 2000
    Date of Patent: April 17, 2001
    Assignee: Headway Technologies, Inc.
    Inventors: Xuehua Wu, Kochan Ju, Jei-Wei Chang
  • Patent number: 6207350
    Abstract: The problem of copper corrosion that occurs in the presence of strong alkaline developing solutions during photo rework has been overcome by protecting all exposed copper bearing surfaces from attack. Two ways of achieving this are described. In the first method, benzotriazole (BTA) is added to the developing solution which is then used in the normal way, developing time being unaffected by this modification. In the second method, the surface that is to receive the photoresist is first given a dip in a solution of BTA, following which the photoresist is immediately applied and processing, including development, proceeds as normal. For both methods the result is the elimination of all copper corrosion during development.
    Type: Grant
    Filed: January 18, 2000
    Date of Patent: March 27, 2001
    Assignee: Headway Technologies, Inc.
    Inventors: Xuehua Wu, Yi-Chun Liu, Jei-Wei Chang, Kochan Ju