Over the last few decades,the aerospace industry has turned increasingly to carbon composite structural materials to make aircraft lighter and more economical. With this increased use, it has become apparent that conventional non-destructive testing (NDT) methods are often impractical or unsuitable for tests of these materials. The ability to find discontinuities (including those introduced during the manufacturing process and those that result from use) in composite structures with conventional non-destructive testing has proven to be challenging.
As a result, Laser Shearography has become one of the primary methods used for non-destructive inspection of composite structures. Laser Shearography is a large area optical inspection technique that uses laser light to detect very slight surface deformations that form when subsurface discontinuities are present and the test part is subjected to an appropriate change in strain. The non contact, full field technique allows large areas to be covered quickly. The results are also near real time.