ULTRASONIC INSPECTING DEVICE

摘要

PURPOSE:To cancel multireflection components in a lens to exactly take out information dependent upon only a defect part by inputting a second ultrasonic signal to a first oscillator by a second oscillator and a second lens. CONSTITUTION:A second oscillator 22 generates ultrasonic oscillation synchro nously with a first oscillator 12 in accordance with the input of an ultrasonic pulse from an ultrasonic transmission means 41. A second lens 21 is held be tween the second oscillator 22 and the first oscillator 12, and the ultrasonic oscillation from the second oscillator 22 is inputted as a second ultrasonic signal P2 to the first oscillator 12. The ultrasonic oscillation generated by the oscillator 12 is radiated as a first ultrasonic signal from a boundary 11a to a body 50 to be inspected, and the input timing to the oscillator 12 and the amplitude level of an ultrasonic signal P are so set that a signal Pl which is reflected by the boundary 11a and is inputted to the oscillator 12 is cancelled by the ultrasonic signal P2. Thus, a reflected signal Pf from the body 50 to be inspected (defect 51) does not disappear by the reflected signal Pl and its multireflection signal.