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. 21, 2026
Filed:
Aug. 29, 2024
Seagate Technology Llc, Fremont, CA (US);
Vivek Krishnamurthy, Eden Prairie, MN (US);
Nathaniel Curran Brandt, Saint Paul, MN (US);
Yong Luo, Medina, MN (US);
Michael Allen Seigler, Eden Prairie, MN (US);
Seagate Technology LLC, Fremont, CA (US);
Abstract
Disclosed are methods and configurations for monitoring reflections in heat-assisted magnetic recording (HAMR) heads that may lead to laser instability and power variation. HAMR heads direct light emitted by a laser toward a near field transducer (NFT) for the production of plasmons that assist in data recording. A certain amount of the laser light may be reflected at or near the NFT back toward the laser, and this reflected light can cause laser instabilities over time. As a screening measure during manufacturing or assembly, or as a laser health monitoring measure during drive operation, a back reflection monitor is used to detect the intensity of a portion of the reflected light. Back reflection monitoring capability may be provided by a bolometer integrated into HAMR recording head assemblies, and optionally along with optical components and electrical circuitry that provides laser light transmission monitoring capability.