METHOD AND DEVICE FOR ULTRASONIC TESTING BY MEANS OF A LINEAR ARRAY AND WITH ECHOSTART

摘要

According to the invention, ultrasound is emitted by a probe and travels over a defined distance to reach a test object (32), and at least one echo signal (51) of the irradiated ultrasound is detected by the probe. The central beam of the ultrasound does not fall upon the surface of the test object (32) at a right angle. A reflection surface (38) is provided between the probe and the test object (32), said surface being outside the central beam, but inside the sound field of the probe. The reflection surface is arranged in such a way that the part of the emitted ultrasound which falls on the reflection surface (38) falls, after reflection, in an essentially right-angled manner on the surface of the test object (32), and is then reflected back therefrom and used as a signal (51) for an echostart. Said probe is a linear array comprising n individual oscillators (22, 24...). A reflection surface (38) is associated with each individual oscillator (22, 24...), and an echostart signal (51) is produced for each individual oscillator (22, 24...). The reception signals (52, 54) which are received by each individual oscillator (22, 24...) are digitalised. Said digitalisation is started individually for each individual oscillator (22, 24...) by means of the echostart signal (52, 54) of the individual oscillator (22, 24...).