ROCK CRYSTAL PIECE MEASURING SYSTEM

PROBLEM TO BE SOLVED: To provide a rock crystal piece measuring system which can surely evaluate the shape of the worked surface of a rock crystal piece in a short time. SOLUTION: An illuminator 12 performs coaxial vertical illumination matched to the photographing optical axis of a camera 13 and a station 11 takes the picture of a work (rock crystal piece) with the camera 13 by making the background of the work nonreflective. A picture processor 15 finds the density difference between the central part and peripheral part of the work from the picture taken with the camera 13 and obtains the evaluation data of the worked shape of the work from the density difference. For example, the processor 15 finds the area or shape of the central part of the work from the density difference and obtains the evaluation data of the worked shape by comparing the area or shape with that of a reference rock crystal piece having a good worked shape. A personal computer 17 controls the picture processing, illumination, work transportation, etc.