Optical convex surface profiling and gauging apparatus and method therefor
US4872757A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 20, 1988 |
| Grant date | Oct 10, 1989 |
| Priority date | — |
| Expiry date | Apr 20, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N21/909
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The present invention utilizes back lighting optics to produce converging white light over an area larger than an area of the edge of the convex object being profiled by the present invention. Opposite the back lighting optics are located a shadow image detector which detects the shadow image of the edge of the convex object, which is located between the back lighting optics and the shadow image detector. The detector generates a plurality of pixel outputs from each of a plurality of vertical locations for the shadow image of the edge. A rotating stage provides relative movement between the convex object and the detector/optics arrangement. The output of the detector which is a high resolution camera is fed into a data processing system which determins a sub-pixel distance measurement for each of the plurality of vertical locations and arranges the sub-pixel distance measurements into rows and columns to construct a surface profile of the convex object.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.