System and method of diffractive focusing of light in a waveguide

US9111558B1 · kind B1 · utility

Assignees

• WESTERN DIGITAL (FREMONT), LLC · US
• THE PROVOST, FELLOWS, FOUNDATION SCHOLARS, AND THE OTHER MEMBERS OF BOARD, OF THE COLLEGE OF THE HOLY AND UNDIVIDED TRINITY OF QUEEN ELIZABETH NEAR DUBLIN · IE

Inventors

• Alexander Krichevsky · Centereach, US
• David McCloskey · Ardee, IE
• Frank Bello · Jackson, US
• Christopher B. Wolf · San Jose, US

Key dates

• Filing date: May 16, 2014
• Grant date: Aug 18, 2015
• Expiry date: May 16, 2034

Classification

• Technology area (CPC G): Physics
• CPC primary: G11B2005/0021
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

A focusing structure including an array of localized optical alterations that alter the propagation of light through the waveguide to diffractively focus the light as it exits the focusing structure. The array of optical alterations may be formed along either a straight or a curved line within a cross section of the focusing structure. In energy assisted magnetic recording apparatus a laser beam propagates through the waveguide to a near field transducer. The waveguide comprises a focusing element that includes an array of localized optical alterations that alter the propagation of the laser beam through the waveguide to diffractively focus the laser beam approximately at the near field transducer.