| 摘要 |
PURPOSE:To reduce the measurement error of thickness propagating time even when front and rear surface echoes vary. CONSTITUTION:When front and rear surface echoes largely vary due to the influence of the surface properties of an object to be inspected 2 or the influence of the profiling mechanism between a probe holding mechanism 4 and the surface of the object 2, the thickness propagating time signal 36 measured by means of a thickness propagating time measuring section 14 becomes an abnormal measured value and a thickness comparing section 15 compares the signal 36 with a thickness propagating time range signal 37 and generates an abnormal trigger signal 38. In addition, a thickness data effective signal generating section 16 generates a thickness data effective signal 39. A thickness data averaging and measuring section 17 calculates a thickness data averaging signal 41 by averaging thickness propagating time signals 36 from which the abnormal measured value is removed based on the signals 36, 39, and 40 and outputs the calculates signal 41. Therefore, the measurement error of thickness propagating time can be reduced. |
