Waveguide power sensor structures free of optical coherence effects in a hamr drive

Abstract

Embodiments disclosed herein generally relate to a HAMR device for use in a magnetic reading system. The HAMR device has a primary waveguide extending from a media facing surface to a surface opposite the media facing surface. In one embodiment, the HAMR head has a secondary waveguide having a first and second end positioned within the HAMR head. The secondary waveguide is positioned near the primary waveguide, and the first and second ends of the secondary waveguide are non-reflecting. A thermal sensor is coupled to the secondary waveguide, and responds only to optical power fluctuations in the primary waveguide. In another embodiment, the HAMR head has a second thermal sensor rather than a secondary waveguide. The first thermal sensor and the second thermal sensor are coupled together to act as one optical power sensor and are disposed on the primary waveguide.

Dependencies are inferred from the claim text.