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Estimation of Specular Light Power by Adjusting Incident Laser Power for Measuring Mirror-Like Surface Roughness  

서영호 (부산대원 지능기계공학과)
김주년 (부산대원 지능기계공학)
안중환 (부산대학교 기계공학부)
Publication Information
Journal of the Korean Society for Precision Engineering / v.21, no.6, 2004 , pp. 94-101 More about this Journal
Abstract
From the Beckmann's reflection model of wave incident, reflected light from a surface is known to have not only specular but also diffuse components. The specular component dominant a surface for a mirror-like surface is distributed on the almost the same area as the spot on the surface, but the diffuse component region dominant f3r a rough surface spreads scattered on the larger areas than the spot. Therefore, statistic parameters from the scattered light distribution are more meaningful in the diffuse region, while the magnitude of rather meaning in the specular region. In usual, there need two sensors to acquire two kinds of information: Photo-detector for light intensity magnitude and image sensor for light intensity distribution. But dual sensor scheme requires a beam splitter usually to feed light to each sensor, and moreover there is not a combination rule to relieve the different sensor characteristics. In this study a new method is proposed for acquisition of the dual information using only an image sensor. Specular region is established on an image area being distinguished from a diffuse component, and laser power is adjusted so that no pixel of the image sensor in the specular region is saturated. Simulation based on the light reflection theory and the experimental results are quite well matched, and thus the proposed method was proved to be very useful for mirror-like surface measurement.
Keywords
Surface roughness; Reflected beam; Specular region; Laser power; Image sensor;
Citations & Related Records
Times Cited By KSCI : 3  (Citation Analysis)
연도 인용수 순위
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