A Technology Assessment of Laser Ultrasonics

The terms Laser Ultrasonics LU and Laser based Ultrasonics LBU relate to a range of testing and measurement configurations that employ lasers both to generate and to detect ultrasonic signals at the surface of opaque materials or in the bulk of transparent media. The ability to perform ultrasonic measurements in a remote and non-contacting manner using laser methods has produced significant interest in this measurement technology from a range of users. Numerous demonstrations of the technology in university, government and industrial laboratories have shown the flexibility and promise of laser ultrasonics and have pointed to its potential limitations. Unlike conventional ultrasonic methods which have experienced broad use in a variety of applications industrial quality control, materials process sensing, medical imaging, infrastructure inspection, laser based methods have been used primarily in research programs and in technology demonstrations. Unfortunately, even with successful demonstrations, the use of laser ultrasonics outside the research environment has not occurred. In part, the movement of this technology to broader application has been limited by the nature of laser ultrasonic technology development.