The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 20, 2006
Filed:
Feb. 23, 2004
Jianmin Wang, Fremont, CA (US);
Jason L. Pressesky, Menlo Park, CA (US);
Huan Tang, Los Altos, CA (US);
Jing Gui, Fremont, CA (US);
Jianmin Wang, Fremont, CA (US);
Jason L. Pressesky, Menlo Park, CA (US);
Huan Tang, Los Altos, CA (US);
Jing Gui, Fremont, CA (US);
Seagate Technology LLC, Scotts Valley, CA (US);
Abstract
An arrangement and method of measuring head-media spacing modulation (HMS_Wq) removes the portion of out-of-plane motion caused by disk modes from the dynamic measurements of hard disk surface topography. Employing time-domain measurement techniques, circumferential surface topographical measurements are made for a hard disk surface. A boundary wavelength is determined, and a first partial HMS_Wq value is determined based upon measurements taken at a first disk rotational speed. A second partial HMS_Wq value is determined based upon measurements taken at a second disk rotational speed. The first and second partial HMS_Wq values are combined to provide a complete and accurate HMS_Wq value, taking advantage of the principle that the disk mode location in the spatial domain topography spectrum converted from the measured time-domain data shifts when the disk rotation speed is changed during the measurement.