Industrially viable non-contact ultrasound

This paper describes some of the research and development of non-contact ultrasonic transducers and techniques that the Warwick Laser Ultrasound Group have made over a number of years. Non-contact ultrasonic techniques are typically not as efficient at generating or detecting ultrasound as conventional contact methods in most types of material and so there needs to be a special need to justify their use. However, non-contact methods do offer some distinct advantages over contacting techniques including their suitability to a range of online measurements. The non-contact ultrasonic techniques described in this paper can and have been used in industrial environments or to inspect and measure a range of industrial samples.