Radius-of-curvature measurement by spectrally-controlled interferometry
US10746537B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Apr 23, 2018 |
| Grant date | Aug 18, 2020 |
| Priority date | — |
| Expiry date | Apr 23, 2038 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01J2009/0253
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The ROC value of a test surface is measured with a single spectrally-controlled interferometric measurement using a reference source of known ROC. The test surface is placed at the confocal position of the reference surface and the light source is modulated so as to produce localized interference fringes at the location of the test surface. The interference fringes are then processed with conventional interferometric analysis tools to establish the exact position of the test surface in relation to the reference surface, thereby determining the distance between the test surface and the reference surface. The radius of curvature of the test surface is obtained simply by subtracting such distance from the known radius of curvature of the reference surface.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.