Optimization of light-source position in appearance inspection for surface with specular reflection

Demands of automatic inspection for appearance of metallic plating parts with specular reflection have been increased. However, the automation of them is difficult because the reflection from surround scene or their strong specular characteristics makes bigger white noise and saturation of brightness. In our recent research, we proposed an algorithm, which can eliminate their strong specular reflection by using image processing technique and multiple images with different light sources, and confirmed its effectiveness. In this paper, in order to correspond to the parts of the three-dimensional shape from the conventional plane parts to be inspected, we examined the optimization method of light-source positions by using three-dimensional reflection model and showed encouraging results obtained by simulation.