This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
New Optical Distortion Measuring Method Using Digital Image Analysis of Projection-Moire Patterns
Annotation ability available
Sector:
Language:
English
Abstract
Optical distortion of images observed through windshields is due to the geometry to a small degree, but to a larger extent, due to effects occurring in production. The detection of manufacturing defects is of primary concern for on-line and off-line inspection procedures. Zebra patterns commonly used to detect serious windshield defects only yield qualitative and highly subjective results. This new method uses fine Moiré screens projected through the inspected windshield on a master grating, directly yielding a full-field fringe pattern directly revealing the line-of-sight deviation. PC-based Digital Image Analysis of the Moiré Fringes permits nearly instantaneous quantitative evaluation yielding a two-dimensional map of distortion levels and deviations. Complete derivation of Fringe-order relations to the measured distortion parameters is included in this paper, as well as a description of the software used in Digital Image Analysis.
Recommended Content
Topic
Citation
Redner, A. and Bhat, G., "New Optical Distortion Measuring Method Using Digital Image Analysis of Projection-Moire Patterns," SAE Technical Paper 970230, 1997, https://doi.org/10.4271/970230.Also In
Progress With Human Factors in Automotive Design: Seating Comfort, Visibility, and Safety
Number: SP-1242; Published: 1997-02-24
Number: SP-1242; Published: 1997-02-24
References
- Irland M.J. “Windshield Optics” SAE Paper # 700480 May 1970
- Uniform Provision Concerning the Approval of Safety Glazing and Glazing Material
- “Standard Practice for Optical Distortion and Deviation of Transparent Parts Using the Double-Exposure Method” ASTM Book of Standards 15-03