The demand for greater product quality in industry has created a need for better and faster techniques for nondestructive testing. Because traditional techniques such as ultrasonic and radiography are rather time consuming, there is a need for more rapid alternatives. Shearography meets that requirement.
Shearography is an optical method that gives information about surface deformation of a loaded structure. The load can be induced by heat, vacuum, pressure, sound, or vibration. The surface area above a defect will deform differently than the surrounding surface area and will be recorded with shearography. Surface deformations of a few microns can be observed.