Abstract
The condition of surface roughness affects the quality of goods, because the light-distribution reflected from the surface depends on the roughness. The relationship between the reflected light-distribution and the roughness, however, does not be made clear. In this study, it is investigated that the correlation between the reflected light-distribution and the parameters representing roughness defined by JISB0601. At first, a simulation is practiced. A roughly finished surface model is designed and the reflected light-distribution is calculated by ray tracing. The relationship between the reflected light-distribution and the parameters representing roughness is examined by the use of the simulated results. As the results, it is found out that the reflected light-distribution is not much correlated with each roughness parameter alone but has a high correlation with the ratio of Ra (arithmetical average roughness) to Sm (mean interval of surface unevenness). For the validity of the simulation, the reflected light-distribution and the parameters representing the surface roughness are really measured on roughly finished plastics. From the experimental results, the same relationship as the simulation is obtained. In addition, the reason why the reflected light-distribution is described as Ra/Sm is mentioned by the use of a surface model.
