Apparatus and method for rotating an optical objective
US11733172B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 6, 2021 |
| Grant date | Aug 22, 2023 |
| Priority date | — |
| Expiry date | May 12, 2041 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2021/8825
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A dark-field optical system may include a rotational objective lens assembly with a dark-field objective lens to collect light from a sample within a collection numerical aperture, where the dark-field objective lens includes an entrance aperture and an exit aperture at symmetrically-opposed azimuth angles with respect to an optical axis, a rotational bearing to allow rotation of at least a part of the dark-field objective lens including the entrance aperture and the exit aperture around the optical axis, and a rotational driver to control a rotational angle of the entrance aperture. The system may also include a multi-angle illumination sub-system to illuminate the sample with an illumination beam through the entrance aperture at two or more illumination azimuth angles, where an azimuth angle of the illumination beam on the sample is selectable by rotating the objective lens to any of the two or more illumination azimuth angles.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.