Recent advances in acoustography for ultrasonic testing

Acoustography is the ultrasonic analog of real time X-ray imaging. It uses a novel two-dimensional acousto-optic sensor for full field, large area, real time image formation through simple shadow casting, similar to X-ray imaging. Recently, we reported two important advances in acoustography: rapid acousto-optic sensors that allow real time video-type imaging capability, and acousto-optic sensors that demonstrate a "memory effect." In this paper, we report on several new capabilities that are becoming apparent With the acoustography approach. The rapid acousto-optic sensors can be employed as a tool for fast ultrasonic testing of components and structures during manufacturing as well as in the field. In addition, we have found that acoustography can also be employed as a fast, cost effective tool for transducer field mapping, which could be important for assuring transducer quality, especially phased array transducers. The memory-type acousto-optic sensor can be used to develop an "acousto-optic patch" device, which is also suitable for field testing of structures and components. These recent developments allow acoustography to offer numerous advantages over conventional ultrasonic testing point-by-point scanning techniques, such as wide area testing, circumvention of bulky mechanical scanning, ease of rise, ability for data to be interpreted by low skill level operators, and simple setup.