Optical alignment system utilizing alignment spot produced by image inverter
US5064286A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 31, 1990 |
| Grant date | Nov 12, 1991 |
| Priority date | — |
| Expiry date | May 31, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B9/02072
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and apparatus is disclosed for aligning a reflective surface with an alignment axis in a representative environment of an interferometer. An image of the reflective surface is focused onto a diffuse screen to form a spot image thereon. Rays of the spot image emanating from the diffuse screen are collimated. Some of the collimated rays are focused onto a detector to form a non-inverted image spot. A portion of the collimated rays are intercepted and inverted by means of an image inverter aligned with the alignment axis. The inverted rays are focused onto the detector to form an inverted image spot. The reflecting surface is moved so as to cause the inverted image spot and the non-inverted image spot to coincide, at which point the reflecting surface is aligned with the alignment axis.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.