Patent · US Expired

Performance test method of head gimgal assembly with precise positioning actuator

US6989949B2 · kind B2 · utility

3Cited by
5References
10Claims
0Family size

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Key dates

Filing dateJan 17, 2003
Grant dateJan 24, 2006
Priority date
Expiry dateAug 4, 2023

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B2005/001
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A method of testing a performance of the HGA has a step of writing information from the at least one thin-film magnetic head element onto a magnetic disk with driving the actuator for displacement by applying an alternating drive signal to the actuator, a step of reading out the information of at least one rotation of the magnetic disk by the at least one thin-film magnetic head element without driving the actuator for displacement, a step of storing the information read-out from the magnetic disk as a read-out information along a disk-rotating direction, a step of moving the HGA toward an off-track direction by a predetermined distance, a step of repeatedly executing the reading, storing and moving steps to obtain two-dimensional read-out information along the disk-rotating direction and the off-track direction, and a step of determining, from the two-dimensional read-out information, an off-track position where the read-out information becomes maximum at each position along the disk-rotating direction, the determined off-track positions being recognized as displaced positions of the actuator in response to the applied alternating drive signal.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.