Evolution of industrial laser-ultrasonic systems for the inspection of composites

For nearly 30 years, laser ultrasonics has been under investigation and development for the inspection of complex composites for the aeronautic industry; however, this technology has failed to achieve widespread adoption. The authors of this paper use their combined experience of over 40 years in the development and use of laser-ultrasonic systems in industrial environments to review the characteristics that appeared to have limited the widespread use of laser ultrasonics in the aeronautic industry. The authors review various technologies that they have explored and developed over the years to address those issues. Finally, a novel laser-ultrasonic approach is described and its capabilities are discussed.