Gloss Evaluation of Hairline-Finished Metal Surface Using Patterned Area Illumination Method: Reproduction of Gloss Evaluation by Ray Tracing
Gloss of a metal surface is an important aspect for product quality evaluation. Evaluating the specular reflection is almost the same as evaluating the gloss. We propose a method that uses patterned area illumination to evaluate specular reflection. In specular reflection, the angle of incidence equ...
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Published in | Key Engineering Materials Vol. 656-657; pp. 468 - 472 |
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Main Authors | , |
Format | Journal Article |
Language | English |
Published |
Zurich
Trans Tech Publications Ltd
23.07.2015
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Subjects | |
Online Access | Get full text |
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Summary: | Gloss of a metal surface is an important aspect for product quality evaluation. Evaluating the specular reflection is almost the same as evaluating the gloss. We propose a method that uses patterned area illumination to evaluate specular reflection. In specular reflection, the angle of incidence equals the angle of reflection. Consequently, when light (ray) of the area illumination, which has a striped pattern, are projected on a glossy metal surface, a striped pattern forms on the reflected image as a mirror-like reflection, and the sharpness of the striped pattern of the image provides information about the specular reflection on the surface. This characteristic is applied to a metal with a hairline surface finish. A hairline surface presents different glossiness at different viewpoints. When the direction of the striped pattern of illumination is changed, the sharpness of striped pattern on the reflected image varies owing to the surface roughness of the hairline finish. Therefore, we can evaluate the glossiness in various directions by rotating the pattern. The relationships between gloss evaluation value and surface roughness were indicated in our study. We tried the reproduction of the gloss evaluation by ray tracing to obtain the more detailed relationships between them. Ray tracing is a technique to generate an image in computer graphics. The approximate reproduction of gloss evaluation was obtained by the simulation. |
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Bibliography: | Selected, peer reviewed papers from the 2014 International Conference on Machining, Materials and Mechanical Technologies (IC3MT), August 31- September 5, 2014, Taipei City, Taiwan ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
ISBN: | 3038354953 9783038354956 |
ISSN: | 1013-9826 1662-9795 1662-9795 |
DOI: | 10.4028/www.scientific.net/KEM.656-657.468 |