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:
Apr. 23, 2013
Filed:
Sep. 07, 2011
Henry Patland, Los Gatos, CA (US);
Juergen Heidmann, Salinas, CA (US);
Wade A. Ogle, San Jose, CA (US);
Alexander M. Taratorin, Palo Alto, CA (US);
Henry Patland, Los Gatos, CA (US);
Juergen Heidmann, Salinas, CA (US);
Wade A. Ogle, San Jose, CA (US);
Alexander M. Taratorin, Palo Alto, CA (US);
Infinitum Solutions, Inc., Santa Clara, CA (US);
Abstract
A property, such as a quality parameter, of a write pole in a write head is determined using an optical metrology device, where the write pole is smaller than the optical resolution limit of the metrology device. The metrology device produces polarized light that is reflected off the write pole while the write pole is magnetized either during or after excitation with a write current. The magnetization alters the polarization state of the light, which can be analyzed to transform the altered polarization state into intensity. The intensity of the light is detected over the point spread function of the optics in the metrology device and an intensity value is generated. The intensity value is used to determine the quality parameter of the write pole, e.g., by comparison to a threshold or reference intensity value, which may be generated empirically or theoretically.