| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a technique for making an apparatus wherein ultrasonic waves are generated by pulse laser beam and received by an electromagnetic ultrasonic sensor, adaptable to a vibration or fluctuations in size of an object to be inspected without providing a complicated mechanism. SOLUTION: The electromagnetic ultrasonic sensor 2 is fixed to the optical surface plate 6 arranged on a two-axis stage 5, and an ultrasonic receiving surface can be brought into contact with a steel pipe 3 or allowed to approach the steel pipe 3 with an arbitrary lift-off by the movement of the two-axis stage 5. A laser beam source 1 is fixed onto the optical surface plate 6 so that emitted laser beam passes through the through-hole of the electromagnetic ultrasonic sensor 2. The following to a flaw detection region can be performed by the two-axis stage 5. Even when the size of the steel pipe 3 changes, the whole of the apparatus is moved by the two-axis stage 5 to be allowed to follow the flaw detection region of the steel pipe 3.</p> |
