Method and apparatus for precision laser micromachining
US6057525A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 10, 1997 |
| Grant date | May 2, 2000 |
| Priority date | — |
| Expiry date | Sep 10, 2017 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB23K2103/52
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A method and apparatus for micromachining and microdrilling which results in a machined part of superior surface quality is provided. The system uses a near diffraction limited, high repetition rate, short pulse length, visible wavelength laser. The laser is combined with a high speed precision tilting mirror and suitable beam shaping optics, thus allowing a large amount of energy to be accurately positioned and scanned on the workpiece. As a result of this system, complicated, high resolution machining patterns can be achieved. A cover plate may be temporarily attached to the workpiece. Then as the workpiece material is vaporized during the machining process, the vapors condense on the cover plate rather than the surface of the workpiece. In order to eliminate cutting rate variations as the cutting direction is varied, a randomly polarized laser beam is utilized. A rotating half-wave plate is used to achieve the random polarization. In order to correctly locate the focus at the desired location within the workpiece, the position of the focus is first determined by monitoring the speckle size while varying the distance between the workpiece and the focussing optics. When the speckl…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.