A method an apparatus are provided for inspecting the surface of objects such as panels for automobile vehicles wherein the surface of the object is sprayed with an oil mist or the like to increase the reflectivity thereof. The surface is then illuminated with light so that the light image reflected...http://www.google.com.tw/patents/US4686374?utm_source=gb-gplus-share專利 US4686374 - Surface reflectivity detector with oil mist reflectivity enhancement
