| 摘要 |
PURPOSE:To inspect the surface of a cylindrical body with the use of the fact that scattering takes place due to a flaw in the surface to reduce the intensity of the reflected light by turning the cylindrical body at a preset speed by a roller and by irradiating the surface with a laser beam having a spot diameter while effecting the scanning operation with the use of a vibratng mirror. CONSTITUTION:A laser beam 2 having a spot diameter is emitted from a laser beam 1 and is canned by a bibrating mirror 3 at a preset position on the surface of a cylindrical body 4 to be measured. This body is turned at a preset speed by means of turning rollers 5 and 5'. The reflected light 6 of the laser beam 2, which has been projected upon the cylindrical body 4, is concentrated upon the light receiving surface of an optical detector 8 by means of a condensing lens 7 so that the signal processing operation such as the judgement of the flaw, and its size and propriety of the test piece may be accomplished by a signal processing circuit 9. |
