Method of detecting opaque foreign article from among transparent bodies utilizing polarized light

摘要: A method of detecting an opaque foreign article from among transparent bodies which assures a distinct difference between detection signals originating body and high S/N ratio in such is improved accuracy operation. The comprises the steps scanning, while object for may be one or existing being moved, by beam linearly polarized light, reflected light upon each scanning using optical sensor as charge coupled device camera way polarizing filter.