International Business Machines Corporation

Iraj Kakesh Pour

Peter Michael Baumgart

James Hammond Brannon

Andrew Ching Tam

Tim Minvielle

Timothy Carl Strand

Chie Ching Poon

Method for laser texturing magnetic recording disk

A laser system is described which concurrently directs highly equivalent diffracted beams derived from an initial laser beam to both sides of a substrate. The diffracted beams may be generated with sufficient energy to soften spots on the surfaces of the substrate to form texture bumps as are used on substrates for magnetic disks. The diffracted beams are generated by a multichannel acousto-optic modulator (MCAOM) having at least two channels. The crystal in the MCAOM has at least two mounting faces oriented so that the acoustic transducers mounted thereon generate acoustic fields which intersect the incident laser beam at a common angle, i.e., the Bragg angle. Energizing any of the transducers causes a corresponding first order beam to be diffracted out. Preferably the diffracted beams are generated by alternating driving signals to transducers to produce two beams with pulse intensity greater than 50% of that of the incident beam which can be directed to opposite sides of a substrate for extremely uniform texturing.

Laser system for simultaneous texturing of two sides of a substrate

Growing community of inventors

San Jose, CA, United States of America

Iraj Kakesh Pour