Patents by Inventor Wai Yuen Lai

Wai Yuen Lai 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: 10395683
    Abstract: A heater power of a heat-assisted magnetic recording head is set based on an initial head-medium clearance estimate in response to the heater power. For a plurality of iterations, an optimum laser power of the recording head is determined and a heater power is set for a next iteration that results in an optimum heater power for the optimum laser power. If differences in the heater and laser powers between two subsequent iterations are below thresholds, the iterations are stopped and the optimum heater power and the optimum laser power for one of the subsequent iterations are used as an operational heater power and an operational laser power.
    Type: Grant
    Filed: September 20, 2018
    Date of Patent: August 27, 2019
    Assignees: Seagate Technology LLC, SAE Magnetics (Hong Kong) Limited
    Inventors: Tim Rausch, Tatsuya Shimizu, Wai Yuen Lai, Kai Chiu Cheung
  • Publication number: 20190019531
    Abstract: A heater power of a heat-assisted magnetic recording head is set based on an initial head-medium clearance estimate in response to the heater power. For a plurality of iterations, an optimum laser power of the recording head is determined and a heater power is set for a next iteration that results in an optimum heater power for the optimum laser power. If differences in the heater and laser powers between two subsequent iterations are below thresholds, the iterations are stopped and the optimum heater power and the optimum laser power for one of the subsequent iterations are used as an operational heater power and an operational laser power.
    Type: Application
    Filed: September 20, 2018
    Publication date: January 17, 2019
    Inventors: Tim Rausch, Tatsuya Shimizu, Wai Yuen Lai, Kai Chiu Cheung
  • Patent number: 8107200
    Abstract: A slider mounted CPP GMR or TMR read head sensor is protected from electrostatic discharge (ESD) damage and from noise and cross-talk from an adjacent write head by means of a balanced resistive/capacitative shunt. The shunt includes highly resistive interconnections between upper and lower shields of the read head and a grounded slider substrate and a low resistance interconnection between the lower pole piece of the write head and the substrate. The capacitances between the pole piece and the upper shield, the upper shield and the lower shield and the lower shield and the substrate are made equal by either forming the shields and pole piece with equal surface areas and separating them with dielectrics of equal thicknesses, or by keeping the ratio of area to insulator thicknesses equal.
    Type: Grant
    Filed: June 19, 2008
    Date of Patent: January 31, 2012
    Assignees: Headway Technologies, Inc., SAE Magnetics (HK) Ltd.
    Inventors: Eric Cheuk Wing Leung, Anthony Wai Yuen Lai, Pak Kin Wong, David Hu, Moris Dovek, Rod Lee
  • Patent number: 7764468
    Abstract: Provided is a smear-removing method that can remove smear of a manufactured thin-film magnetic head. The method is performed to a thin-film magnetic head including an MR effect element for reading data having two electrode layers sandwiching an MR effect multilayer as a magneto-sensitive portion therebetween. The method comprises the step of applying a stress voltage less than a breaking voltage of the MR effect element between the two electrode layers to burn off smear. In the method, it is preferable that the stress voltage is applied while an electric resistance or an output voltage of the MR effect element is measured, and the stress voltage is increased until the value of the electric resistance or the output voltage reaches an upper limit specified value specified from a value of an electric resistance or an output voltage in a normal case where smear is not present.
    Type: Grant
    Filed: April 16, 2007
    Date of Patent: July 27, 2010
    Assignees: TDK Corporation, SAE Magnetics (H.K.) Ltd.
    Inventors: Yoshikazu Sawada, Norio Takahashi, Masaru Hirose, Mitsuo Otsuki, Shoji Toyoda, Anthony Wai Yuen Lai
  • Publication number: 20080273267
    Abstract: A slider has a slider substrate, a read sensor, a top shield and a bottom shield sandwiching the read sensor, and a write shield. The slider substrate is electrically connected to a substrate electrical connection which is adapted to provide a flying height control voltage to the slider substrate for realizing EFH control so that the bottom shield and the write shield both are electrically connected to a ground electrical connection to eliminate pits on shields of the slider as well as reduce electrostatic discharge (ESD) damage and noise during EFH operation. The slider also employs a bottom plate, a heater and a shunting circuit with shunting resistances to optimum reading and/or writing performance by further better preventing noise, cross-talk and ESD. The present invention also discloses a hard disk drive with the slider for adjusting the slider's flying height.
    Type: Application
    Filed: May 1, 2007
    Publication date: November 6, 2008
    Applicant: SAE Magnetics (H.K.) Ltd.
    Inventor: Anthony Wai Yuen Lai
  • Publication number: 20080259506
    Abstract: A slider mounted CPP GMR or TMR read head sensor is protected from electrostatic discharge (ESD) damage and from noise and cross-talk from an adjacent write head by means of a balanced resistive/capacitative shunt. The shunt includes highly resistive interconnections between upper and lower shields of the read head and a grounded slider substrate and a low resistance interconnection between the lower pole piece of the write head and the substrate. The capacitances between the pole piece and the upper shield, the upper shield and the lower shield and the lower shield and the substrate are made equal by either forming the shields and pole piece with equal surface areas and separating them with dielectrics of equal thicknesses, or by keeping the ratio of area to insulator thicknesses equal.
    Type: Application
    Filed: June 19, 2008
    Publication date: October 23, 2008
    Inventors: Eric Cheuk Wing Leung, Anthony Wai Yuen Lai, Pak Kin Wong, David Hu, Moris Dovek, Rod Lee
  • Publication number: 20080251099
    Abstract: Provided is a smear-removing method that can remove smear of a manufactured thin-film magnetic head. The method is performed to a thin-film magnetic head including an MR effect element for reading data having two electrode layers sandwiching an MR effect multilayer as a magneto-sensitive portion therebetween. The method comprises the step of applying a stress voltage less than a breaking voltage of the MR effect element between the two electrode layers to burn off smear. In the method, it is preferable that the stress voltage is applied while an electric resistance or an output voltage of the MR effect element is measured, and the stress voltage is increased until the value of the electric resistance or the output voltage reaches an upper limit specified value specified from a value of an electric resistance or an output voltage in a normal case where smear is not present.
    Type: Application
    Filed: April 16, 2007
    Publication date: October 16, 2008
    Applicants: TDK CORPORATION, SAE Magnetics (H.K.) Ltd.
    Inventors: Yoshikazu SAWADA, Norio Takahashi, Masaru Hirose, Mitsuo Otsuki, Shoji Toyoda, Anthony Wai Yuen Lai
  • Patent number: 7392579
    Abstract: A slider mounted CPP GMR or TMR read head sensor is protected from electrostatic discharge (ESD) damage and from noise and cross-talk from an adjacent write head by means of a balanced resistive/capacitative shunt. The shunt includes highly resistive interconnections between upper and lower shields of the read head and a grounded slider substrate and a low resistance interconnection between the lower pole piece of the write head and the substrate. The capacitances between the pole piece and the upper shield, the upper shield and the lower shield and the lower shield and the substrate are made equal by either forming the shields and pole piece with equal surface areas and separating them with dielectrics of equal thicknesses, or by keeping the ratio of area to insulator thicknesses equal.
    Type: Grant
    Filed: March 7, 2005
    Date of Patent: July 1, 2008
    Assignees: Headway Technologies, Inc., SAE Magnetics (HK) Ltd.
    Inventors: Eric Cheuk Wing Leung, Anthony Wai Yuen Lai, Pak Kin Wong, David Hu, Moris Dovek, Rod Lee