Rapid in situ mastering of an aspheric Fizeau with residual error compensation
US6734979B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 5, 2002 |
| Grant date | May 11, 2004 |
| Priority date | — |
| Expiry date | Nov 5, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01M11/0271
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method with a traceable calibration for reducing the uncertainty in the precision measurement of aspheric surfaces and wavefronts. A transmission sphere is mounted in an interferometer and its emergent wavefront is calibrated by comparing it to an optical sphere that is moved and sampled in a predetermined manner to make it act like a substantially “perfect” sphere mounted on a slideway. Afterwards, the calibrated wavefront from the transmission sphere is used to measure a spherical artifact mounted on the slideway to calibrate its surface. A transmission asphere is then mounted in the interferometer, and its emergent wavefront is calibrated by comparing it to the calibrated spherical artifact mounted on the slideway. The calibrated aspheric wavefront from the interferometer is then used to measure an aspherical artifact mounted on the slideway to determine is surface shape. The calibration of the wavefront emerging from the transmission asphere is periodically updated to provide historical data that is used as the basis for quality improvement and assurance.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.