Patents by Inventor Huazhou Lou
Huazhou Lou 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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Patent number: 11798598Abstract: Described are hard disk drives that include a low density atmosphere, with which is included a passivating gas, and methods of using these hard disk drives and methods of assembling these hard disk drives.Type: GrantFiled: January 28, 2022Date of Patent: October 24, 2023Assignee: Seagate Technology LLCInventors: Bruno Marchon, Dipeshkumar Jayantilal Purani, Tae Young Kim, Huazhou Lou
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Publication number: 20230114979Abstract: A heat-assisted magnetic recording device is disposed in a hermetically sealed enclosure. The device includes a slider comprising a reader, a writer, and an optical waveguide configured to couple light from a light source to a near-field transducer situated at or near an air bearing surface of the slider. The near-field transducer comprises an enlarged portion and a peg extending from the enlarged portion in a direction of the air bearing surface. A fill gas is provided within the enclosure. The fill gas comprises a mixture of a low-density, inert gas and at least one gas that oxidizes carbon, where the total carbon oxidizing gas concentration of the fill gas is 3-50% by volume. In certain embodiments, the fill gas comprises a hydrogen concentration sufficient to retard oxidation of the peg when the peg is at an operating temperature associated with write operations.Type: ApplicationFiled: October 6, 2022Publication date: April 13, 2023Inventors: Robert D. Turner, Yuhang Cheng, Peter W. Kanas, Martin Liam McGarry, Peter Kevin McGeehin, Kevin R. Heim, Edward Charles Gage, Shaikh Mubassar Ali, Huazhou Lou
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Patent number: 11475924Abstract: A heat-assisted magnetic recording device is disposed in a hermetically sealed enclosure. The device includes a slider comprising a reader, a writer, and an optical waveguide configured to couple light from a light source to a near-field transducer situated at or near an air bearing surface of the slider. The near-field transducer comprises an enlarged portion and a peg extending from the enlarged portion in a direction of the air bearing surface. A fill gas is provided within the enclosure. The fill gas comprises a mixture of a low-density, inert gas and at least one gas that oxidizes carbon, where the total carbon oxidizing gas concentration of the fill gas is 3-50% by volume. In certain embodiments, the fill gas comprises a hydrogen concentration sufficient to retard oxidation of the peg when the peg is at an operating temperature associated with write operations.Type: GrantFiled: March 19, 2021Date of Patent: October 18, 2022Assignee: Seagate Technology LLCInventors: Robert D. Turner, Yuhang Cheng, Peter W. Kanas, Martin Liam McGarry, Peter Kevin McGeehin, Kevin R. Heim, Edward Charles Gage, Shaikh Mubassar Ali, Huazhou Lou
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Patent number: 11468918Abstract: A data storage drive includes a rotatable data storage medium, and a head communicatively couplable to the data storage medium. The head includes a temperature sensor and a heater. The data storage drive also includes a ramp for supporting the head when the head is moved away from the data storage medium, and a controller. The controller is configured to obtain first temperature sensor measurement values for different head heater power settings when the head is positioned on the ramp, and is configured to determine an internal pressure of the data storage drive as a function of the first temperature sensor measurement values.Type: GrantFiled: May 17, 2021Date of Patent: October 11, 2022Assignee: SEAGATE TECHNOLOGY LLCInventors: Huazhou Lou, YiMin Niu, Eric John McCalla, Dipeshkumar J. Purani
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Publication number: 20210210121Abstract: A heat-assisted magnetic recording device is disposed in a hermetically sealed enclosure. The device includes a slider comprising a reader, a writer, and an optical waveguide configured to couple light from a light source to a near-field transducer situated at or near an air bearing surface of the slider. The near-field transducer comprises an enlarged portion and a peg extending from the enlarged portion in a direction of the air bearing surface. A fill gas is provided within the enclosure. The fill gas comprises a mixture of a low-density, inert gas and at least one gas that oxidizes carbon, where the total carbon oxidizing gas concentration of the fill gas is 3-50% by volume. In certain embodiments, the fill gas comprises a hydrogen concentration sufficient to retard oxidation of the peg when the peg is at an operating temperature associated with write operations.Type: ApplicationFiled: March 19, 2021Publication date: July 8, 2021Inventors: Robert D. Turner, Yuhang Cheng, Peter W. Kanas, Martin Liam McGarry, Peter Kevin McGeehin, Kevin R. Heim, Edward Charles Gage, Shaikh Mubassar Ali, Huazhou Lou
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Patent number: 10964354Abstract: A heat-assisted magnetic recording device is disposed in a hermetically sealed enclosure. The device includes a slider comprising a reader, a writer, and an optical waveguide configured to couple light from a light source to a near-field transducer situated at or near an air bearing surface of the slider. The near-field transducer comprises an enlarged portion and a peg extending from the enlarged portion in a direction of the air bearing surface. A fill gas is provided within the enclosure. The fill gas comprises a mixture of a low-density, inert gas and at least one gas that oxidizes carbon, where the total carbon oxidizing gas concentration of the fill gas is 3-50% by volume. In certain embodiments, the fill gas comprises a hydrogen concentration sufficient to retard oxidation of the peg when the peg is at an operating temperature associated with write operations.Type: GrantFiled: April 17, 2019Date of Patent: March 30, 2021Assignee: Seagate Technology LLCInventors: Robert D. Turner, Yuhang Cheng, Peter W. Kanas, Martin Liam McGarry, Peter Kevin McGeenhin, Kevin R. Heim, Edward Charles Gage, Shaikh Mubassar Ali, Huazhou Lou
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Publication number: 20190122302Abstract: A method of making periodic retirement fund distributions executed automatically by a computer system comprises a predetermined start date, target end date and frequency of distribution that will provide the investor the exact time duration that the retirement funds will last. The method includes creating a periodic distribution schedule, calculating distribution percentage rate for each distribution, determining the shares to be sold at each distribution while maintaining the remaining funds fully invested. The total distribution time duration is predetermined and fixed. The distribution percentage rate is calculated to create a purchasing power equalized distribution amount in the entire distribution duration by factoring net investment return rate after inflation. The method also includes a cash buffering mechanism to smooth out market fluctuations while providing investment growth.Type: ApplicationFiled: October 23, 2017Publication date: April 25, 2019Inventor: Huazhou Lou
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Patent number: 9928873Abstract: An apparatus comprises a slider configured for writing data to and reading data from a magnetic recording medium and for heat-assisted magnetic recording. The slider comprises a heater configured to receive an AC signal and to cause oscillation in a spacing between the slider and the medium, and a contact sensor situated on the slider and configured to produce a DC response signal. A detector is coupled to the slider and configured to measure an amplitude of a spike in the DC response signal, calculate a ratio between the spike amplitude and an amplitude of the DC response signal, and detect contact between the slider and the medium in response to the ratio exceeding a predetermined threshold.Type: GrantFiled: June 30, 2017Date of Patent: March 27, 2018Assignee: SEAGATE TECHNOLOGY LLCInventors: Dongming Liu, Huazhou Lou, Eric John McCalla, James Robert Oscarson, Shawn S. Silewski
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Patent number: 9824699Abstract: A lumped-parameter function ? is determined that represents an average power dissipated by a write transducer when writing a signal to a magnetic recording medium. Temperatures of the write transducer are measured while varying the parameters to determine constants of the function ?. The function ? is used to adjust power applied to a clearance control heater when writing to the magnetic recording medium.Type: GrantFiled: January 31, 2017Date of Patent: November 21, 2017Assignee: SEAGATE TECHNOLOGY LLCInventors: Huazhou Lou, Jason W. Riddering, Richard Edward Martin, Michael P. DeFeo
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Patent number: 9818439Abstract: A change in servo active gain control values is determined from a beginning of a writing of a test region of a recording medium to an end of the writing of the test region. The servo active gain control values are read from servo marks by a read transducer of a read/write head during the writing. After writing of the test region, the test region is read by the read transducer to determine a change in recorded amplitude from the beginning of the writing to the end of the writing. A gamma value of the read/write head is determined based on the change in servo active gain control values and the change in recorded amplitude.Type: GrantFiled: March 18, 2016Date of Patent: November 14, 2017Assignee: SEAGATE TECHNOLOGY LLCInventors: Jason Riddering, Huazhou Lou
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Patent number: 9792940Abstract: Using a high sample rate dPES, together with pulsed heater and lock-in technique, to improve dPES SNR for contact detection between the head and media surface. Steps of powering a transducing head actuator with pulsed input signal at a select data track offset from a previously-written to data track of the storage medium, where the pulsed input signal has select amplitude and duty cycle to simulate a response signal, and further locking in an amplitude with respect to the heater frequency, can lead to a determination of level of heater power for initiating contact between the transducing head and the storage medium.Type: GrantFiled: March 15, 2013Date of Patent: October 17, 2017Assignee: Seagate Technology LLCInventors: Lin Zhou, Juil Lee, Dongming Liu, Huazhou Lou
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Patent number: 9704529Abstract: A heat-assisted magnetic recording (HAMR) head includes a reader, a writer, a writer heater, a laser, and a near-field transducer (NFT). A processor is coupled to the head and configured to perform laser writeability calibration of the head. The processor is also configured to concurrently while performing the laser writeability calibration, correct for laser induced writer protrusion (LIWP) at a writer/NFT region of the head using writer clearance calculations based on reader clearance measurements.Type: GrantFiled: August 10, 2016Date of Patent: July 11, 2017Assignee: SEAGATE TECHNOLOGY LLCInventors: Huazhou Lou, Jason Riddering
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Patent number: 9607649Abstract: A test involves iterations over a series of laser powers of a heat-assisted read/write head. The iterations involve writing to a recording medium at the selected laser power for a sufficient duration to ensure thermal equilibrium of the read/write head at an end of the write. A clearance-control heater of the read/write head is transitioned from a pre-write power before a start of the write to a steady-state write power. The iterations further involve measuring a temperature of the read/write head during the write and adjusting the steady-state write power to achieve a predefined difference between the temperature at the start of the write and the end of the write. The adjusted steady state write power is stored for each iteration. A write-induced protrusion is determined based on the iterations and used for calibration of the read/write head.Type: GrantFiled: April 8, 2016Date of Patent: March 28, 2017Assignee: SEAGATE TECHNOLOGY LLCInventors: Jason Riddering, Huazhou Lou
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Patent number: 9595277Abstract: Method and apparatus for controlling the fly height of a transducer. In some embodiments, a data pattern is written to a rotating data recording surface using a transducer having a write element, a read element and a thermal assist energy source. A first protrusion distance for the read element induced by operation of the energy source is determined responsive to first and second readback amplitudes obtained from the data pattern using different first and second power levels applied to the energy source. A second protrusion distance for the write element induced by the energy source is determined responsive to the first protrusion distance.Type: GrantFiled: July 13, 2015Date of Patent: March 14, 2017Assignee: Seagate Technology LLCInventors: Huazhou Lou, Jason W. Riddering
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Publication number: 20170018284Abstract: Method and apparatus for controlling the fly height of a transducer. In some embodiments, a data pattern is written to a rotating data recording surface using a transducer having a write element, a read element and a thermal assist energy source. A first protrusion distance for the read element induced by operation of the energy source is determined responsive to first and second readback amplitudes obtained from the data pattern using different first and second power levels applied to the energy source. A second protrusion distance for the write element induced by the energy source is determined responsive to the first protrusion distance.Type: ApplicationFiled: July 13, 2015Publication date: January 19, 2017Inventors: Huazhou Lou, Jason W. Riddering
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Patent number: 9548072Abstract: An apparatus comprises a heat-assisted magnetic recording (HAMR) head, a sensor, and a controller. The HAMR head is configured to interact with a magnetic storage medium. The sensor is configured to produce a signal indicating the occurrence of head-medium contact. The controller is configured to receive the signal and concurrently determine from the signal if the occurrence of head-medium contact is caused by a first contact detection parameter, a second contact detection parameter, or both the first and second contact detection parameters.Type: GrantFiled: February 11, 2015Date of Patent: January 17, 2017Assignee: SEAGATE TECHNOLOGY LLCInventors: Huazhou Lou, Jason Riddering, Shawn S. Silewski, Dongming Liu, Lin Zhou
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Patent number: 9472225Abstract: A magnetic recording head comprises a transducer, a heater, a writer and a laser. The transducer is configured to write to a magnetic recording medium during a write operation. The heater, writer and laser are configured to affect a protrusion of the transducer. The heater is calibrated to produce a pre-write heater power to obtain a target pre-write clearance for a write operation through use of a clearance-heater power curve. The curve is generated by measuring a clearance between the transducer and the medium as the heater is cycled from zero to a contact power.Type: GrantFiled: February 11, 2015Date of Patent: October 18, 2016Assignee: SEAGATE TECHNOLOGY LLCInventors: Huazhou Lou, Jason Riddering
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Publication number: 20160232931Abstract: An apparatus comprises a heat-assisted magnetic recording (HAMR) head, a sensor, and a controller. The HAMR head is configured to interact with a magnetic storage medium. The sensor is configured to produce a signal indicating the occurrence of head-medium contact. The controller is configured to receive the signal and concurrently determine from the signal if the occurrence of head-medium contact is caused by a first contact detection parameter, a second contact detection parameter, or both the first and second contact detection parameters.Type: ApplicationFiled: February 11, 2015Publication date: August 11, 2016Inventors: Huazhou Lou, Jason Riddering, Shawn S. Silewski, Dongming Liu, Lin Zhou
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Publication number: 20160232930Abstract: A magnetic recording head comprises a transducer, a heater, a writer and a laser. The transducer is configured to write to a magnetic recording medium during a write operation. The heater, writer and laser are configured to affect a protrusion of the transducer. The heater is calibrated to produce a pre-write heater power to obtain a target pre-write clearance for a write operation through use of a clearance-heater power curve. The curve is generated by measuring a clearance between the transducer and the medium as the heater is cycled from zero to a contact power.Type: ApplicationFiled: February 11, 2015Publication date: August 11, 2016Inventors: Huazhou Lou, Jason Riddering
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Patent number: 9390741Abstract: A head transducer, configured to interact with a magnetic recording medium, includes a first sensor having a temperature coefficient of resistance (TCR) and configured to produce a first sensor signal, and a second sensor having a TCR and configured to produce a second sensor signal. One of the first and second sensors is situated at or near a close point of the head transducer in relation to the magnetic recording medium, and the other of the first and second sensors spaced away from the close point. Circuitry is configured to combine the first and second sensor signals and produce a combined sensor signal indicative of one or both of a change in head-medium spacing and head-medium contact. Each of the sensors may have a TCR with the same sign (positive or negative) or each sensor may have a TCR with a different sign.Type: GrantFiled: May 22, 2015Date of Patent: July 12, 2016Assignee: SAEGATE TECHNOLOGY LLCInventors: Michael Thomas Johnson, Dongming Liu, Huazhou Lou, Declan Macken, Timothy William Stoebe, James Gary Wessel, Xuan Zheng