| 摘要 |
PURPOSE:To examine defects easily and efficiently by dividing a disc body to plural sector examination areas in the circumferential direction and providing registers in accordance with these areas and obtaining defect information from these registers. CONSTITUTION:A disc body 1 is rotated and driven by a disc rotating motor 2. The laser beam light, which is reflected on this disc body 1, from a laser oscillator 4 is received by a photodetector 6 and is converted to an electrical signal and is inputted to a microcomputer 8 through an interface 7. In this microcomputer 8, defect detection results of sector areas to which the disc body 1 is divided in the circumferential direction are stored in plural registers provided in accordance with these sector areas, and detection positions and sizes of defects are detected, andresults are displayed on a display device 9. |
