Patent ID: 8248898

Claim:
A thermally assisted magnetic recording (TAMR) head comprising: (a) a light source that generates light and transmits said light into a main waveguide and towards an air bearing surface (ABS); (b) the main waveguide for transmitting light to a nearfield device at the ABS, said main waveguide has a lengthwise dimension in a direction perpendicular to the ABS with an end at the ABS, an opposite end facing said light source, and comprising: (1) a first rectangular shaped section from a down-track perspective including the first end at the ABS, a second end formed a first distance from the ABS and interfacing with a first end of a second main waveguide section along a first plane, and two parallel sides between the ABS and first plane; (2) the second section that has a trapezoidal shape, a second end having a greater width in a cross-track direction than the first end at the first plane, and two sides connecting said first and second ends of said second section; and (3) a third section comprising a first end interfacing with the second end of the second section along a second plane that is parallel to the first plane and to the ABS, the second end facing the light source, and two parallel sides aligned perpendicular to the ABS; and (c) an alignment waveguide (AWVG) structure including a first AWVG and a second AWVG each formed along a side of the main waveguide, said first and second AWVG are symmetrically formed about a plane that bisects the main waveguide in the lengthwise direction and each AWVG comprises: (1) a first AWVG section formed substantially parallel to the main waveguide and located a second distance therefrom, said first AWVG section has a width in a cross-track direction, an end with a light outlet at the ABS, and a second end that adjoins a first end of a second AWVG section; (2) the second AWVG section that has a width in the cross-track direction, the first end at an interface with the first AWVG section, and a second end that adjoins a first end of a light coupling section wherein said second end of the second AWVG section is formed a lesser distance from the main waveguide than the first end of the second AWVG section; and (3) the light coupling section formed substantially parallel to a side of the main waveguide and located a coupling gap distance therefrom, said light coupling section captures a certain percentage of light from the main waveguide, and has a width in a cross-track direction, a coupling length, and includes an end facing away from the ABS.