Uneven fringe projection for efficient calibration in high-resolution 3D shape metrology

Journal Article · Mon Aug 20 04:00:00 EDT 2007 · Applied Optics

DOI:https://doi.org/10.1364/AO.46.006113· OSTI ID:21013605

Zonghua, Zhang; Towers, Catherine E; Towers, David P

A novel uneven fringe projection technique is presented whereby nonuniformly spaced fringes are generated at a digital video projector to give evenly spaced fringes in the measurement volume. The proposed technique simplifies the relation between the measured phase and the object's depth independent of pixel position. This method needs just one coefficient set for calibration and depth calculation. With uneven fringe projection the shape data are referenced to a virtual plane instead of a physical reference plane, so an improved measurement with lower uncertainty is achieved. Further,the method can be combined with a radial lens distortion model. The theoretical foundation of the method is presented and experimentally validated to demonstrate the advantages of the uneven fringe projection approach compared with existing methods.Measurement results on a National Physical Laboratory (UK) 'step standard' confirm the measurement uncertainty using the proposed method.

• OSTI ID: 21013605
• Journal Information: Applied Optics, Journal Name: Applied Optics Journal Issue: 24 Vol. 46; ISSN 0003-6935; ISSN APOPAI
• Country of Publication: United States
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
CALIBRATION
IMAGE PROCESSING
IMAGES
LENSES
RESOLUTION