Abstract: A fan-shaped scanning flaw detecting apparatus which includes a probe provided with an ultrasonic wave transmitting-and-receiving array transducer arranged along a circular arc and an acoustic lens for converging and converting an ultrasonic beam transmitted/received by the array transducer into a substantially parallel beam. The apparatus also includes a scanning function section that sequentially switches the transmitting and receiving operation of a group of operative transducer elements of the array transducer so as to make the ultrasonic beam perform fan-shaped scanning. A picturizing processor section forms a sectional image of an object to be examined on the basis of an echo signal obtained from the object to be examined and a display section displays the sectional image. A position detecting section detects a position where the ultrasonic beam is incident to the object to be examined when the probe is moved along a surface of the object to be examined.

Abstract: In a system for irradiating an ultrasonic beam and imaging the insides of plate-shaped and layer-shaped samples, by using the difference between the sound velocities of a liquid medium and a sample from an ultrasonic transducer to the surface of the sample, the focusing condition is arithmetically operated from the distance between the transducer and the imaging surface which is obtained from the surface echo, and a focal point is set to an arbitrary surface in the sample, thereby correcting a phenomenon such that the focal point of the ultrasonic beam focused into the sample non-linearly moves. Thus, even if the sample is distorted, curved, or inclined, the surface can be imaged at a high resolution and a finer imaging picture can be obtained.

Abstract: An ultrasonic flaw detecting apparatus of electronically scanning type comprises a plurality of ultrasonic vibrator elements disposed in an arcuate array, wherein groups of N vibrator elements arrayed in the circumferential direction of an object under test are sequentially changed over to one another on one-by-one base to thereby scan an object under test with ultrasonic beams. By controlling phases of pulse signals applied to the individual vibrator elements, a region of focus of the ultrasonic beams is set at a predetermined depth of the object under test. For reception, only the echoes reflected from a predetermined focal range are selectively extracted by providing corresponding window or gate means.