Low thermal stress catadioptric imaging system
US8786943B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 27, 2011 |
| Grant date | Jul 22, 2014 |
| Priority date | — |
| Expiry date | Oct 1, 2032 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B17/008
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An imaging system having reduced susceptibility to thermally-induced stress birefringence comprising relay optics and projection optics. One of either the relay optics or the projection optics is a reflective optical system that includes reflective optical elements, and the other is a refractive optical system having a negligible or low susceptibility to thermal stress birefringence. The refractive optical system includes: a first group of refractive lens elements located upstream from an aperture stop, and a second group of refractive lens elements located downstream from the aperture stop. The refractive lens elements in the first and second groups that are immediately adjacent to the aperture stop are fabricated using optical materials having a negligible susceptibility to thermal stress birefringence, and the other refractive lens elements in the first and second groups are fabricated using optical materials having at most a moderate susceptibility to thermal stress birefringence.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.