Patents by Inventor Jane Jie Zhang

Jane Jie Zhang 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: 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: 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
  • Patent number: 8174783
    Abstract: Magnetic disk drive systems and associated methods are described for testing magnetic disk performance for certification with a plurality of magnetic disk drive systems prior to installation. The test system may position a slider at a first spacing between the magnetic disk in the slider and simulate the recording performance of a disk drive system with the magnetic disk at the first spacing. The disk drive test system may then transfer a control signal to a heating element in the slider to move the slider to a different spacing between the magnetic disk and the slider to simulate the recording performance of another disk drive system. The test system may, thus, use a single slider to certify a magnetic disk with a plurality of disk drive systems.
    Type: Grant
    Filed: July 23, 2009
    Date of Patent: May 8, 2012
    Assignee: Hitachi Global Storage Technologies Netherlands, B.V.
    Inventors: Shanlin Duan, Zhen Jin, Jane Jie Zhang, Kezhao Zhang
  • Patent number: 8102613
    Abstract: Track pitch in a hard disk drive is selected to satisfy the requirements of both off-track capacity (OTC) and adjacent track interference (ATI). The invention separately measures the track pitch requirements for OTC and ATI. The track pitch for the drive is set with the larger of the OTC and ATI track pitches. The OTC track pitch is measured with a 747 curve, and the ATI track pitch is measured by the positions of adjacent tracks at which the on-track error rate is not worse than a given value after the targeted number of adjacent track writes in the ATI requirement.
    Type: Grant
    Filed: September 25, 2009
    Date of Patent: January 24, 2012
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Shanlin Duan, Zhen Jin, Jane Jie Zhang, Kezhao Zhang
  • Patent number: 7969675
    Abstract: Methods and test systems are disclosed for determining the quality of an erase process for perpendicular magnetic recording (PMR) disks. After performing an erase process on a PMR disk and before the PMR disk is assembled into a hard disk drive, a first test pattern of magnetization pulses is written to a region of the PMR disk. A second test pattern is subsequently read from the region of the PMR disk. The second pattern of magnetization pulses is analyzed in relation to the first test pattern and measured to determine the quality of the erase process.
    Type: Grant
    Filed: November 7, 2008
    Date of Patent: June 28, 2011
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Shanlin Duan, Zhupei Shi, Jane Jie Zhang, Kezhao Zhang
  • Publication number: 20110075286
    Abstract: Track pitch in a hard disk drive is selected to satisfy the requirements of both off-track capacity (OTC) and adjacent track interference (ATI). The invention separately measures the track pitch requirements for OTC and ATI. The track pitch for the drive is set with the larger of the OTC and ATI track pitches. The OTC track pitch is measured with a 747 curve, and the ATI track pitch is measured by the positions of adjacent tracks at which the on-track error rate is not worse than a given value after the targeted number of adjacent track writes in the ATI requirement.
    Type: Application
    Filed: September 25, 2009
    Publication date: March 31, 2011
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Shanlin Duan, Zhen Jin, Jane Jie Zhang, Kezhao Zhang
  • Publication number: 20110019298
    Abstract: Magnetic disk drive systems and associated methods are described for testing magnetic disk performance for certification with a plurality of magnetic disk drive systems prior to installation. The test system may position a slider at a first spacing between the magnetic disk in the slider and simulate the recording performance of a disk drive system with the magnetic disk at the first spacing. The disk drive test system may then transfer a control signal to a heating element in the slider to move the slider to a different spacing between the magnetic disk and the slider to simulate the recording performance of another disk drive system. The test system may, thus, use a single slider to certify a magnetic disk with a plurality of disk drive systems.
    Type: Application
    Filed: July 23, 2009
    Publication date: January 27, 2011
    Inventors: Shanlin Duan, Zhen Jin, Jane Jie Zhang, Kazhao Zhang
  • Publication number: 20100118423
    Abstract: Methods and test systems are disclosed for determining the quality of an erase process for perpendicular magnetic recording (PMR) disks. After performing an erase process on a PMR disk and before the PMR disk is assembled into a hard disk drive, a first test pattern of magnetization pulses is written to a region of the PMR disk. A second test pattern is subsequently read from the region of the PMR disk. The second pattern of magnetization pulses is analyzed in relation to the first test pattern and measured to determine the quality of the erase process.
    Type: Application
    Filed: November 7, 2008
    Publication date: May 13, 2010
    Inventors: Shanlin Duan, Zhupei Shi, Jane Jie Zhang, Kezhao Zhang
  • Patent number: 7529049
    Abstract: Spinstand test improvement that measures Functional Byte Error Rate (F-BER) of a disk. The F-BER is correlated to the BER of a disk. The F-BER test is faster than a BER test. The F-BER test is incorporated into a spinstand tester or the software associated with a spinstand tester.
    Type: Grant
    Filed: September 1, 2006
    Date of Patent: May 5, 2009
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Shanlin Duan, Zhupei Shi, Li Tang, Jane Jie Zhang
  • Publication number: 20080062549
    Abstract: Spinstand test improvement that measures Functional Byte Error Rate (F-BER) of a disk. The F-BER is correlated to the BER of a disk. The F-BER test is faster than a BER test. The F-BER test is incorporated into a spinstand tester or the software associated with a spinstand tester.
    Type: Application
    Filed: September 1, 2006
    Publication date: March 13, 2008
    Inventors: Shanlin Duan, Zhupei Shi, Li Tang, Jane Jie Zhang
  • Patent number: 7271967
    Abstract: A method for determining whether a spike in a read back signal from a read head positioned over a perpendicular recording disk having a magnetically soft underlayer (SUL) is caused by a defect in the SUL or by a thermal asperity (TA). A first read back signal with the spike is obtained in the absence of a local magnetic field near the read head. Then, a permanent magnet or electromagnet is used to induce a small local magnetic field by the read head, and a second signal is obtained. If the signals are substantially similar, a thermal asperity is indicated. Otherwise a defect in the 13 magnetically soft underlayer of the disk is indicated.
    Type: Grant
    Filed: October 28, 2004
    Date of Patent: September 18, 2007
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Zhupei Shi, Li Tang, Jane Jie Zhang, Shanlin Duan
  • 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