Jeffrey T Walker

US Patent:

6347104, Feb 12, 2002

Filed:

Apr 26, 1999

Appl. No.:

09/299824

Inventors:

Sol P. Dijaili - Moraga CA
Jeffrey D. Walker - El Cerrito CA

Assignee:

Genoa Corporation - Fremont CA

International Classification:

H01S 300

US Classification:

372 3801, 372 20, 372 2902, 372 43, 372 70, 359344, 330250

Abstract:

An optical signal power monitor and regulator comprises: a lasing semiconductor optical amplifier for receiving the optical signal and whose laser output is used to monitor a power level of the optical signal; a monitor circuit which receives the laser output and outputs a monitoring signal; a tunable element for receiving a version of the optical signal and whose level of amplification is adjustable and for outputting an amplified optical signal; and a regulator circuit for receiving the monitoring signal and adjusting the amplification of the tunable optical amplifier depending upon the monitoring signal. The tunable element may comprise a tunable gain-clamped semiconductor optical amplifier. Such an embodiment is capable of automatically regulating the tunable element such that a power level of the amplified optical signal is kept stable. In addition, the monitor circuit may be used to send status information regarding the optical signal to a network management system, which in turn may send to the regulator circuit a managing signal affecting the level of amplification to be applied to the optical signal.

US Patent:

6347106, Feb 12, 2002

Filed:

Feb 25, 1999

Appl. No.:

09/257288

Inventors:

Sol P. Dijaili - Moraga CA
Frank G. Patterson - Danville CA
Jeffrey D. Walker - El Cerrito CA
Robert J. Deri - Pleasanton CA
Holly Petersen - Manteca CA
William Goward - Antioch CA

Assignee:

The Regents of the University of California - Oakland CA

International Classification:

H01S 5223

US Classification:

372 46

Abstract:

A highly heat conductive layer is combined with or placed in the vicinity of the optical waveguide region of active semiconductor components. The thermally conductive layer enhances the conduction of heat away from the active region, which is where the heat is generated in active semiconductor components. This layer is placed so close to the optical region that it must also function as a waveguide and causes the active region to be nearly the same temperature as the ambient or heat sink. However, the semiconductor material itself should be as temperature insensitive as possible and therefore the invention combines a highly thermally conductive dielectric layer with improved semiconductor materials to achieve an overall package that offers improved thermal performance. The highly thermally conductive layer serves two basic functions. First, it provides a lower index material than the semiconductor device so that certain kinds of optical waveguides may be formed, e. g.

US Patent:

6443310, Sep 3, 2002

Filed:

Jun 17, 2000

Appl. No.:

09/596347

Inventors:

Thomas W. Adams - Hockley TX
Kenneth W. Seyffert - Houston TX
David W. Largent - Cleveland TX
Jeffrey E. Walker - Lafayette LA
Hector M. Murray - Aberdeen, GB

Assignee:

Varco I/P, Inc. - Houston TX

International Classification:

B07B 149

US Classification:

209399, 209313, 209403, 210488

Abstract:

A screen assembly for a vibratory separator, the screen assembly including a first screen assembly, a frame to which is mounted screening material, at least one seal member on the frame for sealing contact against a second screen assembly. A unibody structure for a first screen assembly for a vibratory separator, the unibody structure having an integral body member with a portion having a plurality of spaced-apart openings therethrough defining a pattern of a plurality of spaced-apart screening openings, the integral body member including side portions foldable to form a pair of spaced-apart integral side members, and at least one seal member on the integral body member for sealing contact of the unibody structure with another item.

US Patent:

6445495, Sep 3, 2002

Filed:

Mar 22, 1999

Appl. No.:

09/273813

Inventors:

Jeffrey D. Walker - El Cerrito CA
Sol P. Dijaili - Moraga CA
Daniel A. Francis - Oakland CA

Assignee:

Genoa Corporation - Fremont CA

International Classification:

H01S 318

US Classification:

359344

Abstract:

A tunable-gain lasing semiconductor optical amplifier comprises a vertical-lasing semiconductor optical amplifier that includes a tunable region which allows the gain of the vertical-lasing semiconductor optical amplifier to be tuned. The tunable region comprises a region whose loss and/or phase may be tuned by adjusting a physical characteristic of the region. For example, the region may comprise a liquid crystal layer whose transmissivity may be adjusted by applying different voltages across the layer to adjust the reflectivity of a cavity mirror, or a cavity mirror whose reflectivity may be adjusted by ion implantation. In an alternative embodiment of this invention, the tunable-gain lasing semiconductor optical amplifier comprises a tunable loss element in series after the gain-clamped semiconductor optical amplifier.

US Patent:

6450345, Sep 17, 2002

Filed:

Jun 27, 2000

Appl. No.:

09/603531

Inventors:

Thomas C. Adams - Hockley TX
Kenneth W. Seyffert - Houston TX
David W. Largent - Cleveland TX
Charles N. Grichar - Houston TX
Vincent D. Leone - Houston TX
Jeffrey E. Walker - Lafayette LA

Assignee:

Varco I/P, Inc. - Houston TX

International Classification:

B07B 149

US Classification:

209399, 209403, 156210, 156291, 1563084, 1563096

Abstract:

A method for making a screen for a vibratory separator, the method including placing at least one layer of screening material below a glue application apparatus, the glue application apparatus including a main body and a plurality of movable glue nozzles movably connected to the body, applying with the movable glue nozzles an amount of glue, in a pattern to at least a portion of the at least one layer of screening material by moving the movable glue nozzles over the at least one layer of screening material. The method wherein the glue application apparatus includes at least one stationary glue nozzle secured immovably to the main body, the method including applying at least one shearable glue bead having a length to the screening material so that shearing the screening material along the length of the at least one shearable glue bead produces separate sections of the screening material.

US Patent:

6512629, Jan 28, 2003

Filed:

Oct 12, 1999

Appl. No.:

09/416817

Inventors:

Sol P. Dijaili - Moraga CA
Jeffrey D. Walker - El Cerrito CA

Assignee:

Genoa Corporation - Fremont CA

International Classification:

H01S 300

US Classification:

359344

Abstract:

A multi-stage lasing semiconductor optical amplifier (SOA) device amplifies an optical signal. The multi-stage SOA includes at least two SOA stages coupled in series. Each SOA stage includes a semiconductor gain medium and a laser cavity including the semiconductor gain medium. The medium is pumped above a lasing threshold for the laser cavity, which clamps the gain of the medium. An optical signal propagating through the medium is amplified by the gain-clamped medium. The SOA stages are characterized by a design parameter which varies from stage to stage. In a preferred embodiment, the design parameter includes a noise figure and a saturable power, with both parameters increasing as the optical signal propagates from stage to stage. As a result, the multi-stage SOA can achieve better noise performance and higher power outputs compared to comparable SOAs of constant noise figure and saturable power.

US Patent:

6549331, Apr 15, 2003

Filed:

Sep 18, 2001

Appl. No.:

09/956175

Inventors:

Jeffrey D. Walker - El Cerrito CA
Sol P. Dijaili - Moraga CA
Richard P. Ratowsky - Castro Valley CA

Assignee:

Genoa Corporation - Fremont CA

International Classification:

H01S 300

US Classification:

359344, 359337

Abstract:

An optical amplifier module that is insensitive to polarization comprises a first fiber, a second fiber, a semiconductor optical amplifier (SOA), and a polarization dependent loss (PDL) unit. The first fiber provides for optical input to the SOA. The SOA amplifies the optical signal received and outputs the amplified signal. The output of the SOA is optically coupled to the PDL unit. The PDL unit provides polarization dependent loss and the loss is preferably selected to match the polarization dependent gain of the SOA such that when two are coupled there is no overall polarization dependence. The output of the PDL is optically coupled to the fiber for transmission output. The present invention also comprises a method for manufacturing an optical amplifier module that comprises the steps of: determining the polarization dependent gain of an SOA, determining the polarization dependent loss of a plurality of PDL units, selecting a PDL unit such that the polarization dependent loss when coupled to the SOA is reduced, and packaging the SOA and the PDL unit as an optical amplifier module.

US Patent:

6560010, May 6, 2003

Filed:

Dec 13, 2001

Appl. No.:

10/016954

Inventors:

Sol P. DiJaili - Moraga CA
Jeffrey D. Walker - El Cerrito CA
Frank G. Patterson - Danville CA

Assignee:

Genoa Corporation - Fremont CA

International Classification:

H01S 300

US Classification:

359344, 359337

Abstract:

A broadband semiconductor optical amplifier (SOA) device includes at least two gain-clamped SOAs having different spectral responses. The gain-clamped SOAs are coupled so that the broadband SOA device has a spectral response which is not attainable by any one of the gain-clamped SOAs. The gain-clamped SOAs may be coupled in different ways. For example, they may be coupled in parallel, in series, or in another different and/or more complex ways. In one implementation, the gain-clamped SOAs are vertically lasing semiconductor optical amplifiers.