Patents by Inventor David D. Nguyen
David D. Nguyen 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).
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METHODS AND SYSTEMS FOR MEASUREMENT AND CONTROL OF CIRCUMFERENTIAL LAYER DISTRIBUTION IN BLOWN FILMS
Publication number: 20230219274Abstract: A sensing system for measurement of a multilayered blown polymeric film. A feedblock supplies polymeric material streams to an annular blown film die to form a plurality of layers of different polymeric materials. A sensing system is positioned adjacent to a film bubble extruded from the blown film die, wherein the blown film bubble includes annular layers of at least two different polymeric materials. The sensing system emits a signal toward selected circumferential positions around the film bubble and receives a plurality of reflected signals at each circumferential position. Each reflected signal in the plurality of reflected signals is generated at an interface between annular layers that includes a refractive index change detectable by the sensing system. A processor processes the reflected signals from the sensing system, and for each circumferential position determines a layer thickness profile for each polymeric material in the film.Type: ApplicationFiled: June 9, 2021Publication date: July 13, 2023Inventors: William W. Merrill, Pradeep P. Bhat, Francis T. Caruso, David L. Hofeldt, David D. Nguyen, Ziang Li -
Patent number: 8865091Abstract: Sample processing devices that include transmissive layers and control layers to reduce or eliminate cross-talk between process chambers in the processing device are disclosed. The transmissive layers may transmit significant portions of signal light and/or interrogation light while the control layers block significant portions of signal light and/or interrogation light. Methods of manufacturing processing devices that include transmissive layers and control layers are also disclosed. The methods may involve continuous forming processes including co-extrusion of materials to form the transmissive layer and control layer in a processing device, followed by formation of the process chambers in the control layer. Alternatively, the methods may involve extrusion of materials for the control layer, followed by formation of process chambers in the control layer.Type: GrantFiled: March 30, 2010Date of Patent: October 21, 2014Assignee: 3M Innovative Properties CompanyInventors: Joel R. Dufresne, Bryan C. Feisel, Theresa J. Gerten, Brent R. Hansen, David D. Nguyen
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Publication number: 20100183479Abstract: Sample processing devices that include transmissive layers and control layers to reduce or eliminate cross-talk between process chambers in the processing device are disclosed. The transmissive layers may transmit significant portions of signal light and/or interrogation light while the control layers block significant portions of signal light and/or interrogation light. Methods of manufacturing processing devices that include transmissive layers and control layers are also disclosed. The methods may involve continuous forming processes including co-extrusion of materials to form the transmissive layer and control layer in a processing device, followed by formation of the process chambers in the control layer. Alternatively, the methods may involve extrusion of materials for the control layer, followed by formation of process chambers in the control layer.Type: ApplicationFiled: March 30, 2010Publication date: July 22, 2010Inventors: Joel R. Dufresne, Bryan C. Feisel, Theresa J. Gerten, Brent R. Hansen, David D. Nguyen
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Patent number: 7718133Abstract: Sample processing devices that include transmissive layers and control layers to reduce or eliminate cross-talk between process chambers in the processing device are disclosed. The transmissive layers may transmit significant portions of signal light and/or interrogation light while the control layers block significant portions of signal light and/or interrogation light. Methods of manufacturing processing devices that include transmissive layers and control layers are also disclosed. The methods may involve continuous forming processes including co-extrusion of materials to form the transmissive layer and control layer in a processing device, followed by formation of the process chambers in the control layer. Alternatively, the methods may involve extrusion of materials for the control layer, followed by formation of process chambers in the control layer.Type: GrantFiled: October 9, 2003Date of Patent: May 18, 2010Assignee: 3M Innovative Properties CompanyInventors: Joel R. Dufresne, Bryan C. Feisel, Theresa J. Gerten, Brent R. Hansen, David D. Nguyen
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Publication number: 20080231049Abstract: Systems and methods for supplying gas to a laser block assembly (LBA). An example system includes a reusable base component and a splitable fill tube with integrated seal head. The base component is attached to a gas supply device. The fill tube is frit bonded to the LBA. The reusable base components includes an internally threaded base section and an externally threaded nut, and the fill tube includes a first end that is secured within the base section when the nut is screwed into the base section. The fill tube is mechanically pinched to make a seal after gas processing has been supplied to the LBA.Type: ApplicationFiled: March 21, 2007Publication date: September 25, 2008Applicant: HONEYWELL INTERNATIONAL INC.Inventors: Christina M. Schober, David D. Nguyen, Robert M. Bowman
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Patent number: 7253582Abstract: A disk drive is disclosed comprising a spindle motor having a plurality of windings including at least a first winding, a second winding, and a third winding. During a spin-up operation, a voltage is applied to the first winding and a first rise time is measured for current flowing through the first winding to reach a predetermined threshold. A voltage is applied to the second winding and a second rise time is measured for current flowing through the second winding to reach a predetermined threshold. A voltage is applied to the third winding and a third rise time is measured for current flowing through the third winding to reach a predetermined threshold. A difference is computed in response to the first rise time, the second rise time, and the third rise time, and an angular position of the spindle motor is estimated by computing an arctangent in response to the difference.Type: GrantFiled: May 28, 2004Date of Patent: August 7, 2007Assignee: Western Digital Technologies, Inc.Inventors: Jianghong Ding, Chuanwen Ji, David D. Nguyen
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Patent number: 7110208Abstract: A method is disclosed for improving servo performance in a disk drive having a plurality of concentric tracks. Each track has a plurality of first-type servo sectors and a plurality of second-type servo sectors. In the method, track identification information and track position information are read from a first-type servo sector. A track number and a transducer position are estimated for a second-type servo sector. Track position information is read from the immediately following second-type servo sector. An odd/even property from the second-type servo sector is compared with an odd/even property for the estimated track number. The odd/even property of the estimated track number is conditionally adjusted such that the odd/even property of the estimated track number matches the odd/even property from the second-type servo sector. A position error signal is determined using the adjusted track number and the track position information read from the second-type servo sector.Type: GrantFiled: July 30, 2004Date of Patent: September 19, 2006Assignee: Western Digital Technologies, Inc.Inventors: Masao Miyamura, David D. Nguyen
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Patent number: 7064918Abstract: A method for reducing a servo channel head gain calibration time comprising initiating a servo channel head gain calibration process for a head corresponding to the selected disk surface; obtaining a head gain calibration value for a pre-selected zone in the selected disk surface; comparing the obtained calibration value with a pre-stored calibration value for the pre-selected zone and generating a comparison result; and stopping the calibration process for the head if the comparison result does not exceed a threshold value.Type: GrantFiled: October 31, 2003Date of Patent: June 20, 2006Assignee: Western Digital Technologies, Inc.Inventors: Raffi Codilian, David D. Nguyen
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Patent number: 7054098Abstract: A disk drive is disclosed comprising a disk, an actuator arm, a head connected to a distal end of the actuator arm, and a voice coil motor (VCM) for rotating the actuator arm about a pivot to actuate the head over the disk, wherein the VCM rotates the actuator arm into a latched positioned when the disk drive is idle. Disk drive control circuitry unlatches the actuator arm by applying a driving current to the VCM according to an open-loop current profile. The open-loop current profile comprises an acceleration pulse having an acceleration magnitude and an acceleration interval, and a deceleration pulse having a deceleration magnitude and a deceleration interval. The deceleration magnitude is substantially smaller than the acceleration magnitude, and the deceleration interval is substantially longer than the acceleration interval, to thereby attenuate acoustic noise when unlatching the actuator arm.Type: GrantFiled: June 1, 2004Date of Patent: May 30, 2006Assignee: Western Digital Technologies, Inc.Inventors: Jie Yu, David D. Nguyen
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Patent number: 7035026Abstract: A method of manufacturing a disk drive and a disk drive where the width of the read element and the width of the write element are both measured at servo-writing time and the track pitch of the disk drive is set on the basis of those measurements. Disk drives with superior head width combinations are servo-written with a narrower track pitch in order to have a higher storage capacity. Disk drives with inferior head width combinations are detected before servo-writing so that the disk drive may be servo-written with wider track pitch rather than with a nominal track pitch that results in a subsequent drive failure during initial burn-in (IBI). The heads are used more efficiently in that heads that are more capable are used to their ability and less capable heads that would otherwise be disposed of are used at all.Type: GrantFiled: November 1, 2004Date of Patent: April 25, 2006Assignee: Western Digital Technologies, Inc.Inventors: Raffi Codilian, William D. Johns, Charles A. Park, David D. Nguyen, Jack M. Chue
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Patent number: 6967811Abstract: A disk drive comprising a first seek operating mode to move the actuator over a seek distance D in a seek time T1, using a first seek profile for minimizing T1, wherein for a first repetitive series of seeks over distance D a servo control system would require a delay time TD between seeks to control temperature rise in a VCM. A second seek operating mode to move the actuator over the seek distance D in a second seek time T2 using a second seek profile for limiting the temperature rise in the VCM, wherein for a second repetitive series of seeks over the seek distance D, a time average TAVG of the T2 seek times is substantially less than T1+TD.Type: GrantFiled: July 2, 2004Date of Patent: November 22, 2005Assignee: Western Digital Technologies, Inc.Inventors: Raffi Codilian, David D. Nguyen, Alexander Babinski
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Patent number: 6924959Abstract: A method for reducing an estimation period for repeatable runout (RRO) errors in a disk drive comprising a head, a disk surface having a track partitioned by servo-wedges, and a servo control system for controlling the movement of the head relative to a track during revolutions of the disk. The method includes estimating the RRO errors of the track based on a) a series of position error signal values obtained during a current revolution of the disk surface, and b) a previous estimation of the RRO errors of the track obtained during a previous revolution of the disk surface and determining a differential value between a first measure of the estimated RRO errors and a second measure of the previous estimation of RRO errors, and repeating the estimating and determining for subsequent revolutions of the disk surface until the determined differential value is smaller than a pre-selected threshold value.Type: GrantFiled: August 29, 2003Date of Patent: August 2, 2005Assignee: Western Digital Technologies, Inc.Inventors: Hemant Melkote, Robert J. McNab, David D. Nguyen, John Yin Kwong Li
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Patent number: 6900958Abstract: A method is disclosed for improving head position accuracy in a disk drive during track following of concentric data storage tracks through real-time identification of external vibration and monitoring of write-unsafe (WUS) occurrences. In the method, after a seek operation to a predetermined data storage track, the track is followed using a servo control loop having a nominal gain and responsive to a position error signal (PES). After waiting a vibration detection delay period, occurrences of the PES exceeding a WUS limit are counted generating a WUS limit exception count. Also, a property of a variance is determined from spectral power values generated from the PES during track following. If the WUS limit exception count exceeds a first threshold, and if the property of the variance exceeds a second threshold, the nominal gain is increased to a vibration gain within a frequency band, to attenuate the effect of external vibration.Type: GrantFiled: July 31, 2003Date of Patent: May 31, 2005Assignee: Western Digital Technologies, Inc.Inventors: Li Yi, Yanbin Song, David A. Spaulding, Arafat M. Butt, Robert J. McNab, David D. Nguyen
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Patent number: 6885514Abstract: A method of manufacturing a disk drive and a disk drive made with such method where the width of the read element and the width of the write element are both measured at servo-writing time and the track pitch of the disk drive is set on the basis of those measurements. Disk drives with superior head width combinations are servo-written with a narrower track pitch in order to have a higher storage capacity. Disk drives with inferior head width combinations are detected before servo-writing so that the disk drive may be servo-written with wider track pitch rather than with a nominal track pitch that results in a subsequent drive failure during initial burn-in (IBI). The heads are used more efficiently in that heads that are more capable are used to their ability and less capable heads that would otherwise be disposed of are used at all. Fewer disk drives are required to be reworked and returned to the servo-writing process.Type: GrantFiled: July 31, 2001Date of Patent: April 26, 2005Assignee: Western Digital Technologies, Inc.Inventors: Raffi Codilian, William D. Johns, Charles A. Park, David D. Nguyen, Jack M Chue
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Patent number: 6791785Abstract: A controller for a disk drive that accesses a look up table having a plurality of thermally characterized values corresponding to a plurality of seek operations. For each seek operation, the corresponding value is added to a register. The controller decrements the register at a rate that is determined using servo interrupts occurring as a result of the rotation of the disk. When the value of the register exceeds a threshold, the controller adjusts the subsequent seek operation so as to inhibit damage to the voice coil as a result of overheating.Type: GrantFiled: February 28, 2001Date of Patent: September 14, 2004Assignee: Western Digital Technologies, Inc.Inventors: Carl R. Messenger, David D. Nguyen
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Patent number: 6676869Abstract: Described is a method of indirect printing on a thermoplastic film having texture, wherein said method comprises: a) providing a heated thermoplastic melt; b) providing a tool having a molding portion that comprises a texture having a surface and a plurality of cavities in said surface, and that comprises a material having a surface energy sufficient to release ink; c) applying ink to said texture; d) substantially drying or curing said ink; e) contacting said thermoplastic melt with said molding portion having ink applied to it; f) forming a texture in said thermoplastic melt, wherein said texture comprises a plurality of protrusions and an area between said protrusions, that is the inverse of the texture of said molding surface; g) transferring said ink from said molding portion to said thermoplastic melt; h) quenching said thermoplastic melt to form a thermoplastic film; and i) removing said thermoplastic film from said molding portion.Type: GrantFiled: December 21, 2001Date of Patent: January 13, 2004Assignee: 3M Innovative Properties CompanyInventors: Brandon T. Berg, Tony B. Hollobaugh, David D. Nguyen, Bruce H. Koehler, Bruce A. Nerad
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Publication number: 20030118783Abstract: Described is a method of indirect printing on a thermoplastic film having texture, wherein said method comprises: a) providing a heated thermoplastic melt; b) providing a tool having a molding portion that comprises a texture having a surface and a plurality of cavities in said surface, and that comprises a material having a surface energy sufficient to release ink; c) applying ink to said texture; d) substantially drying or curing said ink; e) contacting said thermoplastic melt with said molding portion having ink applied to it; f) forming a texture in said thermoplastic melt, wherein said texture comprises a plurality of protrusions and an area between said protrusions, that is the inverse of the texture of said molding surface; g) transferring said ink from said molding portion to said thermoplastic melt; h) quenching said thermoplastic melt to form a thermoplastic film; and i) removing said thermoplastic film from said molding portion.Type: ApplicationFiled: December 21, 2001Publication date: June 26, 2003Inventors: Brandon T. Berg, Tony B. Hollobaugh, David D. Nguyen, Bruce H. Koehler, Bruce A. Nerad
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Patent number: 6579601Abstract: Conformable multilayer films having alternating layers of a stiff polymeric material and a flexible polymeric material are described.Type: GrantFiled: February 7, 2001Date of Patent: June 17, 2003Assignee: 3M Innovative Properties CompanyInventors: Richard A. Kollaja, David D. Nguyen, Ronald S. Steelman, Buren R. Ree, Steven D. Solomonson, Philip D. Radovanovic
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Publication number: 20010008687Abstract: Conformable multilayer films having alternating layers of a stiff polymeric material and a flexible polymeric material are described.Type: ApplicationFiled: February 7, 2001Publication date: July 19, 2001Applicant: 3M Innovative Properties CompanyInventors: Richard A. Kollaja, David D. Nguyen, Ronald S. Steelman, Buren R. Ree, Steven D. Solomonson, Philip D. Radovanovic
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Patent number: 6231629Abstract: An abrasive article is provided which comprises a backing; and at least one three-dimensional abrasive coating comprising diamond particles dispersed within a binder bonded to a surface of the backing, the binder comprising a cured binder precursor including a urethane acrylate oligomer. The abrasive article is capable of rapid glass stock removal coupled with reducing the surface finish as indicated by reduced Ra values using an RPP test procedure.Type: GrantFiled: September 4, 1998Date of Patent: May 15, 2001Assignee: 3M Innovative Properties CompanyInventors: Todd J. Christianson, David D. Nguyen, Robert G. Visser, Soon C. Park