Full-field three-dimensional measurement method
US7545516B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 1, 2006 |
| Grant date | Jun 9, 2009 |
| Priority date | — |
| Expiry date | Sep 11, 2027 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B11/2527
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and system for full-field fringe-projection for 3-D surface-geometry measurement, referred to as “triangular-pattern phase-shifting” is disclosed. A triangular grey-scale-level-coded fringe pattern is computer generated, projected along a first direction onto an object or scene surface and distorted according to the surface geometry. The 3-D coordinates of points on the surface are calculated by triangulation from distorted triangular fringe-pattern images acquired by a CCD camera along a second direction and a triangular-shape intensity-ratio distribution is obtained from calculation of the captured distorted triangular fringe-pattern images. Removal of the triangular shape of the intensity ratio over each pattern pitch generates a wrapped intensity-ratio distribution obtained by removing the discontinuity of the wrapped image with a modified unwrapping method. Intensity ratio-to-height conversion is used to reconstruct the 3-D surface coordinates of the object. Intensity-ratio error compensation involves estimating intensity-ratio error in a simulation of the measurement process with both real and ideal captured triangular-pattern images obtained from real and ideal gamm…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.