# US 2010/0165802 A1 · Ridge wave-guide for thermal assisted magnetic recording > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2010/0165802 A1 - Document ID: US20100165802A1 - Status: Published application - Kind: A1 - Application number: 12/347,194 - Filed: 2008-12-31 - Published: 2010-07-01 - Earliest claimed: 2008-12-31 - Assignees: Hitachi Global Storage Technologies Netherlands B.V. - Inventors: Barry Cushing Stipe - Web page: https://patentgrep.com/patent/US20100165802A1 ## CPC - G11B 5/314: {where the layers are extra layers normally not provided in the transducing structure, e.g. optical layers (G11B5/3196 takes precedence)} - G11B 7/1387: using the near-field effect - G11B 2005/001: {Controlling recording characteristics of record carriers or transducing characteristics of transducers by means not being part of their structure} - G11B 2005/0021: {Thermally assisted recording using an auxiliary energy source for heating the recording layer locally to assist the magnetization reversal} - G11B: INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER (recording measured values in a way that does not require playback through a transducer G01D9/00; recording or playback apparatus using mechanically marked tape, e.g. punched paper tape, or using unit records, e.g. punched or magnetically marked cards G06K; transferring data from one type of record carrier to another G06K1/18; circuits for coupling output of reproducer to radio receiver H04B1/20; gramophone pick-ups or like acoustic electromechanical transducers or circuits therefor H04R) ## Abstract According to one embodiment, an apparatus includes a near field transducer comprising a conductive metal film having a main body with front and back edges and a ridge extending from the front edge of the main body. Also, the apparatus includes an optical waveguide for illumination of the near field transducer, wherein a distance between the ridge and the back edge of the main body is between about 60 and about 240 nanometers. ## Claims ### Claim 1 An apparatus, comprising: a near field transducer comprising a conductive metal film having a main body with front and back edges and a ridge extending from the front edge of the main body, the ridge extending from the front edge in a direction away from the back edge; and an optical waveguide for illumination of the near field transducer, wherein a distance between an edge of the main body from which the ridge extends and the back edge of the main body is between about 60 and about 240 nanometers. ### Claim 2 (depends on 1) The apparatus as recited in claim 1, wherein the distance is between about 80 and about 160 nanometers. ### Claim 3 (depends on 1) The apparatus as recited in claim 1, wherein the conductive metal film has a C aperture formed therein. ### Claim 4 (depends on 1) The apparatus as recited in claim 1, wherein the conductive metal film has an E shape. ### Claim 5 (depends on 1) The apparatus as recited in claim 1, wherein the conductive metal film includes wings extending from the main body. ### Claim 6 (depends on 1) The apparatus as recited in claim 1, wherein the back edge is about aligned with a core layer of the optical waveguide. ### Claim 7 (depends on 1) The apparatus as recited in claim 1, wherein the optical waveguide includes a core layer, wherein a center of the core layer is about aligned with the ridge. ### Claim 8 An apparatus, comprising: a near field transducer comprising a conductive metal film having a main body with front and back edges and a ridge extending from the front edge of the main body; and an optical waveguide for illumination of the near field transducer, wherein a distance between an edge of the main body from which the ridge extends and the back edge of the main body is between about 25% and about 75% of a wavelength of a surface Plasmon on the near field transducer when illuminated. ### Claim 9 (depends on 8) The apparatus as recited in claim 8, wherein the distance is between about 45% and about 55% of the wavelength of the surface Plasmon on the near field transducer when illuminated. ### Claim 10 (depends on 8) The apparatus as recited in claim 8, wherein the conductive metal film has a C aperture formed therein. ### Claim 11 (depends on 8) The apparatus as recited in claim 8, wherein the conductive metal film has an E shape. ### Claim 12 (depends on 8) The apparatus as recited in claim 8, wherein the conductive metal film includes wings extending from the main body. ### Claim 13 (depends on 8) The apparatus as recited in claim 8, wherein the back edge is about aligned with a core layer of the optical waveguide. ### Claim 14 (depends on 8) The apparatus as recited in claim 8, wherein the optical waveguide includes a core layer, wherein a center of the core layer is about aligned with the ridge. ### Claim 15 An apparatus, comprising: a near field transducer comprising a conductive metal film having a main body with front and back edges and a ridge extending from the front edge of the main body; and an optical waveguide for illumination of the near field transducer, wherein the back edge is about aligned with a core layer of the optical waveguide. ### Claim 16 An apparatus, comprising: a near field transducer comprising a conductive metal film having a main body with front and back edges and a ridge extending from the front edge of the main body; and an optical waveguide for illumination of the near field transducer, wherein the back edge is about aligned with a core layer of the optical waveguide, wherein a distance between the front edge and the back edge of the main body is between about 25% and about 75% of a wavelength of a surface Plasmon on the near field transducer when illuminated. ### Claim 17 An apparatus, comprising: a near field transducer comprising a conductive metal film having a main body with front and back edges and a ridge extending from the front edge of the main body; and an optical waveguide for illumination of the near field transducer, wherein the back edge is about aligned with a core layer of the optical waveguide, wherein a distance between the ridge and the back edge of the main body is between about 45% and about 55% of the wavelength of the surface Plasmon on the near field transducer when illuminated. ### Claim 18 (depends on 15) The apparatus as recited in claim 15, wherein a distance between the ridge and the back edge of the main body is between about 60 and about 240 nanometers, the ridge extending from the front edge in a direction away from the back edge. ### Claim 19 (depends on 15) The apparatus as recited in claim 15, wherein the distance is between about 80 and about 160 nanometers. ### Claim 20 (depends on 15) The apparatus as recited in claim 15, wherein the conductive metal film has a C aperture formed therein. ### Claim 21 (depends on 15) The apparatus as recited in claim 15, wherein the conductive metal film has an E shape. ### Claim 22 (depends on 15) The apparatus as recited in claim 15, wherein the conductive metal film includes wings extending from the main body. ### Claim 23 (depends on 15) The apparatus as recited in claim 15, wherein the core layer delivers light energy, wherein a center of the core layer is about aligned with the ridge.