Analysis Method on Effect of Inactive Elements in a Phased Array Ultrasonic Probe Using Full Matrix Capture

Some of the array elements in a phased array ultrasonic probe can become inactive temporarily or permanently during use. Array probes are expensive, thus, it would not be cost-effective to terminate use because of a few damaged elements or consider a series of examinations as invalid if a single element was discovered to have become inactive during examination. Therefore, it is necessary to be able to use a phased array probe even if some of its elements are inoperative. In order to support this technically, it is required to assess the influence of inactive elements on phased array ultrasonic inspection results and to determine how many inactive elements are acceptable for the inspection. In this study, we developed a method to evaluate the effect of inactive elements in a phased array ultrasonic probe using a reconstructed ultrasonic signal and image through post-processing data acquired via full matrix capture for various numbers and patterns of inactive elements. The results were compared to those inspected by conventional phased array ultrasonic testing, and the proposed method was validated.