Grating based laser and power monitor for a heat-assisted magnetic recording device
AssigneeSeagate Technology LLC
InventorsMichael Allen Seigler, Delai Zhou
Life of this patent
Estimating the term…
Abstract
A head assembly includes a submount, a body with a first surface, an optical path, a near field transducer (NFT), a sensor, and a laser. The optical path is disposed in the body and is adapted to receive light and convey the light to a distal end of the waveguide. The near field transducer (NFT) is disposed adjacent the distal end of the waveguide and has an output end proximate the first surface of the body. The sensor interfaces with the submount and the laser is attached to the submount along a non-primary lasing surface. The laser is adapted to inject light into the waveguide and includes a grating adapted to diffract a portion of the light through the non-primary lasing surface to the sensor.
Claims20
A head assembly, comprising:
- a submount;
- a body having a first surface;
- an optical path disposed in the body and adapted to receive light and convey the light to a distal end of the optical path;
- a near field transducer (NFT) disposed adjacent the distal end of the optical path and having an output end proximate the first surface of the body;
- a sensor interfacing with the submount;
- and
- a laser attached to the submount along a non-primary lasing surface thereof, wherein the laser is adapted to inject light into the optical path and includes a grating adapted to diffract a portion of the light through the non-primary lasing surface to the sensor.
A heat assisted magnetic recording device, comprising:
- a slider body;
- a read/write element disposed proximate the slider body and configured to apply a magnetic field to write data on a portion of a heat-assisted magnetic recording medium in response to an energizing current;
- a submount attached to the slider body;
- a photodiode interfacing with the submount;
- and
- a laser attached to the submount and disposed above the photodiode, wherein the laser is adapted to inject light proximate the read/write element and includes a grating adapted to diffract a portion of the light to the photodiode.
A method, comprising:
- generating laser light from a laser diode;
- coupling the laser light into an optical path having a distal end;
- directing a first portion of the laser light toward a near field transducer (NFT) located at the distal end, the first portion of laser light exciting the near field transducer to surface plasmonic resonance;
- diffracting a second portion of the laser light in a direction normal to a direction of the first portion of the laser light;
- sensing the second portion of diffracted laser light to monitor an output power of the laser diode;
- and
- applying an energizing current to a write element to write data to a portion of a media.
Dependencies are inferred from the claim text.