1998 Volume 22 Issue 1 Pages 1_46-1_52
In an automatic inspection system, the improvement of image quality has a close relation with the detecting device and the inspected object. It is difficult to determine the relation among the detecting lens, the surface roughness, and the reflectance of inspected object by analytics or measuring methods. In this paper, the reflection characteristic of the inspected object in an automatic inspection system is studied by means of Monte Carlo (MC) method. The theoretical analysis and simulation results reveal as follows: if the inspected objects have the same reflectance and the same surface roughness, the number and the standard deviation of photon bundles are related to the radius of the lens and the shape of inspected object. A change in the specular reflectance has greater influence on the number of reflected photon bundles than that of the diffuse reflectance. However, with the increase of the surface roughness, the photon bundles received by the lens decrease, and the influence of the specular reflectance on the number of reflected photon bundles becomes similar in number to the diffuse reflectance.
