PHY08 Ultrasonic B-Scan

The conversion of the amplitude values of an amplitude scan into grey scale or colour values and the presentation of the time of flight as penetration depth yield a line of points with different brightness and/or colour values. The stringing together of such adjoining depth scans of an ultrasonic probe, which is guided along a line over the test area produces a sectional image, the so-called B-Scan image. Localisation along this line is based on the position of the probe and its movement speed. A simple way to obtain a B-Scan image is to guide the ultrasonic probe slowly by hand (compound scan). Scan quality is here dependent upon the coordinate-accurate transferral of scan points, the axial and lateral resolution of the ultrasonic probe, the grey scale and/or colour value resolution, the number of lines and imaging errors. In order to achieve e.g. exact lateral resolution, an additional coordinate-recording system is necessary such as a linear scanner.

Screenshot of the measuring software in B scan mode

The screen shot of the measurement software shows the B-Scan presentation of the investigation of a sample with defined, built-in defects. The manual scanning of the block makes the functioning of the B-Scan method “easy to grasp”. The problems of movement artefacts with regard to lateral resolution caused “by hand” can be reduced by a mechanical scanning (PHY16).