Applications of digital shearography for testing of composite structures

This paper reviews shearography and its applications for testing of composi te structures. Shearography is a laser-based technique for fullfield measur ement of surface deformation. Unlike holography, it does not require specia l vibration isolation; hence it can be employed in field/factory environmen ts. The technique has already received considerable industrial acceptance f or nondestructive testing of composite structures. In this application shea rography reveals defects in an object by looking for defect-induced deforma tion anomalies. Other applications include strain measurement, material cha racterization, residual stress evaluation, vibration studies and 3-D shape measurement. (C) 1999 Elsevier Science Ltd. All rights reserved.