Surface shape measuring apparatus and method
US6721056B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 16, 2000 |
| Grant date | Apr 13, 2004 |
| Priority date | — |
| Expiry date | Aug 16, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B11/24
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An apparatus for measuring the surface shape of the surface to be measured of an optical system to be measured includes a rotary stage holding the optical system to be measured thereon and rotatable about the optical axis of the optical system to be measured, a device for detecting the rotation azimuth of the rotary stage, an irradiating optical system for sequentially applying a coherent light beam to the plurality of measuring diameter positions of the surface to be measured of the optical system to be measured held on the rotary stage, a light receiving element for detecting the reflected light of the coherent light beam from the surface to be measured as an interference signal, and a calculating system for effecting the measurement of the surface shape of the surface to be measured on the basis of the result of the detection of the interference signal at each of the plurality of measuring diameter positions of the surface to be measured and the result of the detection by the rotation azimuth detecting device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.