Application of digital phase-shift shadow Moiré to micro deformation measurements of curved surfaces
| Autor: | W. Van Paepegem, Joris Degrieck, Pierre Michel Boone |
|---|---|
| Rok vydání: | 2001 |
| Předmět: |
Surface (mathematics)
Materials science business.product_category Field (physics) business.industry Mechanical Engineering Process (computing) Grating Deformation (meteorology) Atomic and Molecular Physics and Optics Electronic Optical and Magnetic Materials Optics Sensitivity (control systems) Electrical and Electronic Engineering business Intensity (heat transfer) Digital camera |
| Zdroj: | ResearcherID |
| ISSN: | 0143-8166 |
| Popis: | The shortcomings of conventional shadow Moire topography have in the past been improved by means of the phase-shift method which enhances the sensitivity and allows to process the fringe patterns automatically. This paper presents a digital implementation of the phase-shifting process, which requires only one image to be taken. The grating lines, projected onto the deformed object surface, are captured directly with a digital camera. Next the reference grating is superimposed numerically onto the projected grating lines. Then a number of phase-shifts are performed taking into account the non-linearities in the expression for the height-dependent intensity field. Experimental results prove that these non-linearities can considerably affect the micro deformation measurements of curved surfaces. The proposed method is very efficient and eliminates all causes of erroneous measurements due to the miscalibration of phase-stepping devices. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect