Data storage device detecting NFT contamination by measuring thermal gradient and magnetic write width
AssigneeWestern Digital Technologies, Inc.
InventorsSukumar Rajauria, Robert Lee Smith, Taiebeh Tahmasebi
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Abstract
A data storage device is disclosed comprising a head actuated over a magnetic media, wherein the head comprises a write element, a read element, a laser, and a near field transducer. An operating thermal gradient of the magnetic media is periodically measured at an operating power setting for the laser that achieves a target magnetic write width. When a slope of the operating thermal gradient exceeds a threshold, a test thermal gradient and magnetic write width of the magnetic media is measured at multiple power settings for the laser in order to detect a contamination of the near field transducer.
Claims20
A data storage device comprising:
- a magnetic media;
- a head actuated over the magnetic media, wherein the head comprises a write element, a read element, a laser, and a near field transducer;
- and
- control circuitry configured to:
- periodically measure an operating thermal gradient of the magnetic media at an operating power setting for the laser that achieves a target magnetic write width;
- and
- when a slope of the operating thermal gradient exceeds a threshold, measure a test thermal gradient and magnetic write width of the magnetic media at multiple power settings for the laser in order to detect a contamination of the near field transducer.
A data storage device comprising:
- a magnetic media;
- a head actuated over the magnetic media, wherein the head comprises a write element, a read element, a laser, and a near field transducer;
- and
- control circuitry configured to measure a test thermal gradient and magnetic write width of the magnetic media at multiple power settings for the laser in order to detect a contamination of the near field transducer.
A data storage device comprising:
- a magnetic media;
- a head actuated over the magnetic media, wherein the head comprises a write element, a read element, a laser, and a near field transducer;
- and
- control circuitry configured to:
- periodically measure an operating thermal gradient of the magnetic media at an operating power setting for the laser that achieves a target magnetic write width;
- and
- when a slope of the operating thermal gradient exceeds a threshold, measure an offset between the write element and the read element in order to detect a contamination of the near field transducer.
A data storage device comprising:
- a magnetic media;
- a head actuated over the magnetic media, wherein the head comprises a write element, a read element, a laser, and a near field transducer;
- and
- a means for measuring a test thermal gradient and magnetic write width of the magnetic media at multiple power settings for the laser in order to detect a contamination of the near field transducer.
Dependencies are inferred from the claim text.