Patent ID: 8406090
Filing Date: 2013-03-26
Classification: G11B

Abstract:
1. An apparatus for monitoring laser power for thermally assisted recording on magnetic media, the apparatus comprising: a laser that delivers a laser light to a head element and a hotspot on a rotational magnetic medium, a first portion of the laser light contacting the head element to heat the head element and a second portion of the laser light contacting the hotspot to heat the hotspot, wherein the first portion of the laser light is prevented from contacting the hotspot by the head element; wherein the head element is coupled to an electrical lead, the head element registering an electrical resistance change to electricity flowing through the electrical lead and head element in response to a temperature change in the head element produced by the head element absorbing a portion of the laser light before the laser light is delivered to the rotational magnetic medium; a measurement module coupled to the electrical lead, the measurement module measuring the electrical resistance change; and a determination module that determines a power level of the laser in response to the electric resistance change.