Patents by Inventor Jizhong He

Jizhong He 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).

  • Patent number: 9428384
    Abstract: The present disclosure relates an inspection instrument adapted to increase testing throughput in a manufacturing process. In one embodiment, the inspection instrument includes a base plate and a vertical frame, where the base plate and the vertical frame are configured to provide structural support of the inspection instrument, a first mounting mechanism coupled to the base plate, where the first mounting mechanism is configured to hold a sample for inspection, and a second mounting mechanism coupled to the vertical frame, where the second mounting mechanism is configured to hold a set of sensors and an optical system for inspecting the sample. The first mounting mechanism and the second mounting mechanism are decoupled from each other to reduce impact of movements of the sample to the set of sensors and the optical system.
    Type: Grant
    Filed: January 17, 2012
    Date of Patent: August 30, 2016
    Inventor: Jizhong He
  • Patent number: 8958178
    Abstract: Reducing slider bounce within a hard disk drive. A force is received at a first material while the first material is in contact with a disk of a hard disk drive; the first material comprising a portion that is flexible in a first direction and is substantially non-flexible in a second direction. The first direction is a direction that is normal to the disk and the second direction is a direction that is parallel to a surface of the disk. The force is substantially absorbed by the portion that is flexible to reduce the force associated with interaction between the first material and the disk, thereby reducing slider bounce within the hard disk drive.
    Type: Grant
    Filed: July 29, 2009
    Date of Patent: February 17, 2015
    Assignee: HGST Netherlands B.V.
    Inventors: Shanlin Duan, Jizhong He, John Stephen Hopkins
  • Patent number: 8618793
    Abstract: A tool for testing a magnetic disk for use in a magnetic disk drive. The tool detects surface defects or asperities by detecting a change in electrical resistance corresponding to a temperature change in a thermally sensitive layer. The apparatus includes a slider body having a thermally insulating layer formed on an air bearing surface of the slider body and a thermal sensor layer formed on the thermally insulating layer. The thermally insulating layer prevents thermal heat spikes in the thermal sensor layer (such as resulting from contact with an asperity) from dissipating quickly into the slider body itself. The thermal sensor layer is a material that exhibits a change in electrical resistance in response to a change in temperature and is preferably a PTC thermistor material which exhibits a large change in electrical resistance when a transition temperature has been reached.
    Type: Grant
    Filed: December 23, 2009
    Date of Patent: December 31, 2013
    Assignee: HGST Netherlands B.V.
    Inventors: Shanlin Duan, Jizhong He, John S. Hopkins, Kenneth E. Johnson
  • Patent number: 8395857
    Abstract: Approaches for a testing device for selecting a discrete track media (DTM) format for use with a particular head of a hard-disk drive (HDD). The testing device comprises a continuous magnetic-recording disk, rotatably mounted on a spindle, which stores data using a continuous media format. The testing device also comprises a testing module configured to simulate reading data, stored using a discrete track media (DTM) format, from the continuous magnetic-recording medium. Advantageously, testing time and cost is reduced as both discrete track media (DTM) disks and expensive discrete track media (DTM) recording testing hardware are not required to select the optimal a discrete track media (DTM) format for use with a particular head of a hard-disk drive (HDD). In addition, embodiments may be used to optimize features of the tracks of the DTM disk, such as the land to groove ratio.
    Type: Grant
    Filed: November 8, 2010
    Date of Patent: March 12, 2013
    Assignee: HGST Netherlands B.V.
    Inventors: Kezhao Zhang, Jizhong He, Shanlin Duan, Jane Jie Zhang, Zhupei Shi
  • Publication number: 20120182412
    Abstract: The present disclosure relates an inspection instrument adapted to increase testing throughput in a manufacturing process. In one embodiment, the inspection instrument includes a base plate and a vertical frame, where the base plate and the vertical frame are configured to provide structural support of the inspection instrument, a first mounting mechanism coupled to the base plate, where the first mounting mechanism is configured to hold a sample for inspection, and a second mounting mechanism coupled to the vertical frame, where the second mounting mechanism is configured to hold a set of sensors and an optical system for inspecting the sample. The first mounting mechanism and the second mounting mechanism are decoupled from each other to reduce impact of movements of the sample to the set of sensors and the optical system.
    Type: Application
    Filed: January 17, 2012
    Publication date: July 19, 2012
    Inventor: Jizhong HE
  • Publication number: 20120113538
    Abstract: Approaches for a testing device for selecting a discrete track media (DTM) format for use with a particular head of a hard-disk drive (HDD). The testing device comprises a continuous magnetic-recording disk, rotatably mounted on a spindle, which stores data using a continuous media format. The testing device also comprises a testing module configured to simulate reading data, stored using a discrete track media (DTM) format, from the continuous magnetic-recording medium. Advantageously, testing time and cost is reduced as both discrete track media (DTM) disks and expensive discrete track media (DTM) recording testing hardware are not required to select the optimal a discrete track media (DTM) format for use with a particular head of a hard-disk drive (HDD). In addition, embodiments may be used to optimize features of the tracks of the DTM disk, such as the land to groove ratio.
    Type: Application
    Filed: November 8, 2010
    Publication date: May 10, 2012
    Inventors: Kezhao Zhang, Jizhong He, Shanlin Duan, Jane Jie Zhang, Zhupei Shi
  • Publication number: 20110149706
    Abstract: A tool for testing a magnetic disk for use in a magnetic disk drive. The tool detects surface defects or asperities by detecting a change in electrical resistance corresponding to a temperature change in a thermally sensitive layer. The apparatus includes a slider body having a thermally insulating layer formed on an air bearing surface of the slider body and a thermal sensor layer formed on the thermally insulating layer. The thermally insulating layer prevents thermal heat spikes in the thermal sensor layer (such as resulting from contact with an asperity) from dissipating quickly into the slider body itself. The thermal sensor layer is a material that exhibits a change in electrical resistance in response to a change in temperature and is preferably a PTC thermistor material which exhibits a large change in electrical resistance when a transition temperature has been reached.
    Type: Application
    Filed: December 23, 2009
    Publication date: June 23, 2011
    Inventors: Shanlin Duan, Jizhong He, John S. Hopkins, Kenneth E. Johnson
  • Patent number: 7946156
    Abstract: Glide test systems and associated methods are described. A glide test system includes a glide test head that is flown over the surface of a recording disk to detect asperities on the recording disk. The glide test head includes a detection pad on the trailing end of the head. Heating elements are fabricated proximate to the detection pad. The heating elements are independently controllable to control the amount of protrusion of different regions of the detection pad. The heating elements thus provide a way to substantially flatten the detection surface of the detection pad, and compensate for an uneven topography on a detection surface.
    Type: Grant
    Filed: December 26, 2007
    Date of Patent: May 24, 2011
    Assignee: Hitachi Global Storage Technologies Netherlands, B.V.
    Inventors: Shanlin Duan, Jizhong He, Bruno Marchon, Ullal V. Nayak
  • Publication number: 20110026167
    Abstract: Reducing slider bounce within a hard disk drive. A force is received at a first material while the first material is in contact with a disk of a hard disk drive; the first material comprising a portion that is flexible in a first direction and is substantially non-flexible in a second direction. The first direction is a direction that is normal to the disk and the second direction is a direction that is parallel to a surface of the disk.
    Type: Application
    Filed: July 29, 2009
    Publication date: February 3, 2011
    Inventors: Shanlin Duan, Jizhong He, John Stephen Hopkins
  • Publication number: 20100142344
    Abstract: A method models and calibrates the fly height of a slider above the disk for disk drives. The calibration scheme uses the Wallace spacing loss equation and laser doppler velocimetry to predict fly height and detect the actual fly height of the slider. The slider is vibrated at selected resonances, such as by capacitive coupling to the disk, and the fly height is gradually reduced. In one version, contact between the slider and disk may be detected using an arm electronics sensor. The amplitude of mean-to-peak, vibration detection is used as an indication of the actual fly height and to calibrate the modeled fly height.
    Type: Application
    Filed: February 22, 2010
    Publication date: June 10, 2010
    Applicant: HITACHI GLOBAL STORAGE TECHNOLOGIES NETHERLANDS BV
    Inventors: Shanlin Duan, Jizhong He, John Stephen Hopkins, Yansheng Luo
  • Patent number: 7724462
    Abstract: A method models and calibrates the fly height of a slider above the disk for disk drives. The calibration scheme uses the Wallace spacing loss equation and laser doppler velocimetry to predict fly height and detect the actual fly height of the slider. The slider is vibrated at selected resonances, such as by capacitive coupling to the disk, and the fly height is gradually reduced. In one version, contact between the slider and disk may be detected using an arm electronics sensor. The amplitude of mean-to-peak, vibration detection is used as an indication of the actual fly height and to calibrate the modeled fly height.
    Type: Grant
    Filed: August 1, 2008
    Date of Patent: May 25, 2010
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Shanlin Duan, Jizhong He, John Stephen Hopkins, Yansheng Luo
  • Patent number: 7692888
    Abstract: An apparatus, system, and method are disclosed for fly height detection. The apparatus includes an actuator configured to induce vibrations in a glide head that is configured to detect physical asperities on a disk surface. The apparatus may also include a second end of the suspension arm coupled with the glide head and a sensor module that is configured to communicate with a control module in response to the glide head coming in contact with at least one physical asperity. The system includes the apparatus, a disk having a surface comprising physical asperities, and a head gimbal assembly configured to calibrate a fly height margin for the disk. The method includes inducing vibrations in a glide head, detecting physical asperities on a disk surface, and communicating with a control module in response to the glide head coming in contact with at least one physical asperity.
    Type: Grant
    Filed: December 12, 2006
    Date of Patent: April 6, 2010
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Shanlin Duan, Jizhong He, John Stephen Hopkins
  • Publication number: 20100027152
    Abstract: A method models and calibrates the fly height of a slider above the disk for disk drives. The calibration scheme uses the Wallace spacing loss equation and laser doppler velocimetry to predict fly height and detect the actual fly height of the slider. The slider is vibrated at selected resonances, such as by capacitive coupling to the disk, and the fly height is gradually reduced. In one version, contact between the slider and disk may be detected using an arm electronics sensor. The amplitude of mean-to-peak, vibration detection is used as an indication of the actual fly height and to calibrate the modeled fly height.
    Type: Application
    Filed: August 1, 2008
    Publication date: February 4, 2010
    Applicant: HITACHI GLOBAL STORAGE TECHNOLOGIES NETHERLANDS BV
    Inventors: Shanlin Duan, Jizhong He, John Stephen Hopkins, Yansheng Luo
  • Publication number: 20090165539
    Abstract: Glide test systems and associated methods are described. A glide test system includes a glide test head that is flown over the surface of a recording disk to detect asperities on the recording disk. The glide test head includes a detection pad on the trailing end of the head. Heating elements are fabricated proximate to the detection pad. The heating elements are independently controllable to control the amount of protrusion of different regions of the detection pad. The heating elements thus provide a way to substantially flatten the detection surface of the detection pad, and compensate for an uneven topography on a detection surface.
    Type: Application
    Filed: December 26, 2007
    Publication date: July 2, 2009
    Inventors: Shanlin Duan, Jizhong He, Bruno Marchon, Ullal V. Nayak
  • Publication number: 20080137225
    Abstract: An apparatus, system, and method are disclosed for fly height detection. The apparatus includes an actuator configured to induce vibrations in a glide head that is configured to detect physical asperities on a disk surface. The apparatus may also include a second end of the suspension arm coupled with the glide head and a sensor module that is configured to communicate with a control module in response to the glide head coming in contact with at least one physical asperity. The system includes the apparatus, a disk having a surface comprising physical asperities, and a head gimbal assembly configured to calibrate a fly height margin for the disk. The method includes inducing vibrations in a glide head, detecting physical asperities on a disk surface, and communicating with a control module in response to the glide head coming in contact with at least one physical asperity.
    Type: Application
    Filed: December 12, 2006
    Publication date: June 12, 2008
    Inventors: Shanlin Duan, Jizhong He, John Stephen Hopkins
  • Patent number: 7173415
    Abstract: A magnetic test module runs on a spin stand to detect amplitude decay and noise evolution at the same time. Signal-to-noise ratio (SNR) decay is directly measured. The recording performance is correlated better with SNR instead of signal only. The thermal stability of the system is evaluated more accurately with this SNR decay method. A heater is placed under the media disk, and a remote sensing thermometer and temperature controller form a subsystem to set up desired environmental temperature. The heater creates a heated band and the read/write head flies above the heated band. The temperature control system may be removed when SNR decay measurement is performed under room temperature.
    Type: Grant
    Filed: July 26, 2005
    Date of Patent: February 6, 2007
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Shanlin Duan, Jizhong He, Zhupei Shi, Jane Jie Zhang
  • Publication number: 20070024276
    Abstract: A magnetic test module runs on a spin stand to detect amplitude decay and noise evolution at the same time. Signal-to-noise ratio (SNR) decay is directly measured. The recording performance is correlated better with SNR instead of signal only. The thermal stability of the system is evaluated more accurately with this SNR decay method. A heater is placed under the media disk, and a remote sensing thermometer and temperature controller form a subsystem to set up desired environmental temperature. The heater creates a heated band and the read/write head flies above the heated band. The temperature control system may be removed when SNR decay measurement is performed under room temperature.
    Type: Application
    Filed: July 26, 2005
    Publication date: February 1, 2007
    Inventors: Shanlin Duan, Jizhong He, Zhupei Shi, Jane Zhang