Method and apparatus for detecting surface deviations from a reference plane
US5311288A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 6, 1992 |
| Grant date | May 10, 1994 |
| Priority date | — |
| Expiry date | Jul 6, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B11/306
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and apparatus for detecting deviation of an examined surface from a reference plane, by: generating first and second beams of radiation, directing the first beam along a first fixed path and focussing it at a first spot on the examined surface, directing the second beam along a second fixed path intersecting the first path at a point in the reference plane and focussing the second beam to a second spot on the examined surface, and detecting the deviation of the centers of the first and second spots with respect to the intersection point in the reference plane to provide an indication of the deviation of the examined surface from the reference plane.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.