Optical metrology device for precision angular measurement of a pointing mirror
US6188078A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 4, 1999 |
| Grant date | Feb 13, 2001 |
| Priority date | — |
| Expiry date | May 4, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B27/62
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A method and apparatus measure the accuracy of and optically calibrate a scan mirror. Both the method and apparatus may operate over a wide range of environmental conditions. The environmental conditions may include variations in pressure from a vacuum to several atmospheres. Similarly, large variations in temperature may be accommodated. The apparatus includes a laser source, a plurality of facet mirrors and a detector. The laser source projects a beam onto a reflective surface of a rotatable scan mirror, which directs the beam to each of the plurality of facet mirrors. Each facet mirror is positioned at a known angle. Each facet mirror in turn reflects the beam from the reflective surface of the scan mirror substantially back onto itself (autocollimation). The angle detector then receives the reflected beam and measures a value related to a return angle of the beam.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.