SYSTEMS AND METHOD FOR ILLUMINATING AND EVALUATING SURFACES

摘要

Systems and methods for illuminating an object surface with light at varying angles of incidence and for optically evaluating the object surface for features and defects, etc. are disclosed. In a specific implementation the systems and methods, the target object comprises a coin and the illumination and evaluation techniques are used to accurately objectively evaluate the numismatic quality of the coin and/or identify the coin. Central to the illumination and evaluation techniques is the ability to apply a uniform confined beam of light to the surface of the target object to be imaged. The confined angles of incidence of the beam of light includes a perpendicular component angle of incidence range and a parallel component angle of incidence range relative to the object surface. The component ranges are defined such a light beam illuminates the object surface from a well-defined direction. The direction and the extent of light beam illumination may be varied by redefining one or both of the component angle of incidence ranges. In addition to identifying features and defects of a coin surface, the illumination and evaluation techniques are capable of imaging the surface lustre of the coin.