Laser system for simultaneous texturing of two sides of a substrate
US5981903A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 28, 1997 |
| Grant date | Nov 9, 1999 |
| Priority date | — |
| Expiry date | Mar 28, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F1/332
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.