Optical inspection system with polarization isolation of detection system reflections
US8436997B2 · kind B2 · utility
2Cited by
15References
20Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Dec 17, 2010 |
| Grant date | May 7, 2013 |
| Priority date | — |
| Expiry date | Nov 9, 2031 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2201/0642
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An optical inspection system includes a polarizing isolator that reduces error in measurements by preventing ghost light reflected or scattered from element of a detection subsystem from re-entering the illumination and detection optical paths. The polarizing isolator may include a polarizing splitter that isolates light directionally according the a linear polarization state and two quarter-wave plates for transforming linearly polarized light to circularly polarized light.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.